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Let's say that a function which returns a fixed 'random text' string is written like
char *Function1()
return "Some text";
What are the square brackets after the function call attempting to do that would make the program crash? If you're familiar with this, any explanation would be greatly appreciated!
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The [1] is pointing to the 2nd character in the string ([0] would be the first) – climbage Nov 19 '10 at 16:10
Why do you say C++ in the title, yet tag the question C? – GManNickG Nov 19 '10 at 17:03
You should mark this as MSVC since gcc (at least >= 4) would warn you about assigning a char const [] to a char * is deprecated...for good reasons as you see. – Rüdiger Stevens Nov 19 '10 at 17:54
7 Answers 7
up vote 12 down vote accepted
The string you're returning in the function is usually stored in a read-only part of your process. Attempting to modify it will cause an access violation. (EDIT: Strictly speaking, it is undefined behavior, and in some systems it will cause an access violation. Thanks, John).
This is the case usually because the string itself is hardcoded along with the code of your application. When loading, pointers are stablished to point to those read-only sections of your process that hold literal strings. In fact, whenever you write some string in C, it is treated as a const char* (a pointer to const memory).
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You can't say that it will cause an access violation. C++ doesnt know anything about access violations. All you can really say is that it will evoke undefined behavior – John Dibling Nov 19 '10 at 16:23
_USER_: you're right. Take it in the philosophical meaning then :) – Diego Sevilla Nov 19 '10 at 16:27
_USER_: Maybe "will" is too string but you have a good chance that it will :-) – Rüdiger Stevens Nov 19 '10 at 17:56
_USER_: On Windows it might GPF. On linux it might segfault. On my phone it might call my mother. Point is it's UB. – John Dibling Nov 19 '10 at 18:20
The signature of that function should really be constchar* Function();.
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Completely agree. – Diego Sevilla Nov 19 '10 at 16:15
it should actually be std::string since OP wants to modify the value retued from the function – John Dibling Nov 19 '10 at 16:23
Yes, John, in C++ - sure, in C - that's the only way. – Nikolai N Fetissov Nov 19 '10 at 17:02
You are trying to modify a string literal. According to the Standard, this evokes undefined behavior. Another thing to keep in mind (related) is that string literals are always of type const char*. There is a special dispensation to convert a pointer to a string literal to char*, taking away the const qualifier, but the underlying string is still const. So by doing what you are doing, you are trying to modify a const. This also evokes undefined behavior, and is akin to trying to do this:
const char* val = "hello";
char* modifyable_val = const_cast(val);
modifyable_val[1] = 'n'; // this evokes UB
Instead of returning a const char* from your function, return a string by value. This will construct a new string based on the string literal, and the calling code can do whatever it wants:
_TAG_
std::string Function1()
return "Some text";
std::string s = Function1();
s[1] = 'a';
Now, if you are trying to change the value that Function() reuturns, then you'll have to do something else. I'd use a class:
_TAG_
class MyGizmo
 std::string str_;
 MyGizmo() : str_("Some text") {};
int main()
 MyGizmo gizmo;
 gizmo.str_[1] = 'n';
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You can use static char string for return value, but you never use it. It's just like access violation error. The behavior of it is not defined in c++ Standard.
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Ofcourse you can use it. You just can't modify its contents. – larsmans Nov 19 '10 at 16:18
ohya, exactly. and one more thing(just like jobs...:), as many other guys said already, converting constant char string into non-constant char string is blah blah blah...you know~ – Hongseok Yoon Nov 19 '10 at 16:26
It's not the brackets, but the assignement. Your function returns not a simple char *, but const char *( i can be wrong here, but the memory is read-only here), so you try to change the unchangeable memory. And the brackets - they just give you access to the element of the array.
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Note also that you can avoid the crash by placing the text in a regular array:
char Function1Str[] = "Some text";
char *Function1()
 return Function1Str;
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The question shows that you do not understand the string literals.
image this code
char* pch = "Here is some text";
char* pch2 = "some text";
char* pch3 = "Here is";
Now, how the compiler allocates memory to the strings is entirely a matter for the compiler. the memory might organised like this:
Here isHere is some text
with pch2 pointing to memory location inside the pch string.
The key here is understanding the memory. Using the Standard Template Library (stl) would be a good practice, but you may be quite a steep learning curve for you.
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text:
People have been using fire to provide heat for thousands of years. However, a lot has changed since the time of the open fires used by our ancestors. Storch fireplace stoves and inserts use a highly sophisticated modern combustion system that guarantees an environmentally friendly solution to heating.
Burning wood produces a similar amount of carbon dioxide (CO2) to the decomposition of wood in a forest. The environment is therefore not burdened by excessive carbon dioxide production. This means that burning wood does not increase the greenhouse effect like other fossil fuels - coal, oil or gas. Furthermore, wood is a renewable energy source, while coal, oil and gas have limited supplies.
Storch manufactures environmentally friendly stoves and inserts that meet the strictest environmental standards. All STORCH fireplace heating units are tested in compliance with valid legal regulations and EN 13 240 and EN 13 229 (European standard). Because they comply with the European technical standard, all our stoves and inserts are marked CE "Conformité Européenne". Products with this label come with a guarantee of not only a lower negative impact on the environment, but also of high quality.
It can certainly be said that it is every user's responsibility to ensure that they use their stove or insert correctly and without endangering the environment. To achieve this goal, we would like to remind you of the following principles:

source: openbmb/Ultra-FineWeb


text:
"Most climate models assume that roots are shallow -- usually within 6 feet of the surface -- and that only the soil moisture near the surface can significantly impact the climate," said Praveen Kumar, a professor of civil and environmental engineering at the University of Illinois at Urbana-Champaign. "Our research shows that it is not just the near surface, but also the deep reservoir of soil moisture that affect terrestrial heat and moisture processes in land-atmosphere interaction."
A better understanding of this interaction, Kumar said, could lead to more accurate climate models and better predictability.
Using a land surface model, Kumar and graduate student Geremew Amenu are assessing the effects of deep roots on soil moisture and temperature redistribution. Three sites with different vegetation, soil and climate characteristics are being studied: the Mogollon Rim in Arizona, the Edwards Plateau in Texas and the Southern Piedmont in Georgia. Soil depths of up to 30 feet are being investigated.
There are two primary mechanisms by which deep-layer moisture affects the soil surface, Kumar said. First, its temporal variability sets the lower boundary for the transfer of moisture and heat from the surface. And second, this temporal variability influences the uptake of moisture by the plant roots, resulting in the variability of the transpiration and therefore the entire energy balance.
"Our initial results suggest that this second mechanism is predominant, indicating that accurate specification of rooting depth in climate models will play a crucial role in improving predictability," Kumar said.

source: HuggingFaceFW/fineweb-edu


text:
iHub Research, today presented a report on a study they undertook in 2014 to assess how ICT tools are being used, for and in various aspects of governance in Kenya, Uganda and Tanzania. This study, with an aim to bridge the research and insights gap on ICT use in East Africa, sought to answer the following:
- Which ICT tools are used in Kenya, Uganda and Tanzania addressing these four aspects of governance,
- Access to information
- Service delivery
- Tracking corruption
- Citizen participation
- In which ways are ICT tools used in the above four areas?
- What successes and challenges exist in the use of these tools?
The presenter Ms. Varyanne Sika from iHub Research Kenya said that In Uganda 1Government agency, 11 Civil Society Organizations, 2 Developers and 36 Focus Group Discussion Participants were interviewed and the rest from Kenya and Tanzania.
There exist numerous websites, mobile phone and web applications for governance which are not used as often as the developers expected because of two key reasons:
Successful uses of ICTs in governance have been found in cases where nonInternet based ICTs such as radio and mobile phones (feature phones) are used, or in areas where forums exist for citizens to physically meet then follow up on issues raised using ICTs. Mobile and web applications, which are created mostly in tech hubs and tech competitions such as hackathons, are popular and hyped only among people who are particularly interested in technology and applications. Few people are reached through the app creators' marketing strategies, if at all there are any such attempts. Radios are the most common ICT tools in many rural areas; many success stories were reported among the organizations which use radios to make information on various governance issues accessible to citizens.
Citizens are motivated by the ease provided by ICT tools to interact with government and CSOs. The use of ICT is increasingly diminishing the fear of getting victimised thus boosting citizens' morale to leverage ICTs in reporting issues affecting them in society.
A key demotivation in the two-way interaction between citizens and government using ICTs is the belief by citizens that nothing will come out of the interaction. A demotivating factor for using ICTs in interacting with citizens on the part of government and CSOs, is costs involved in setting up and running ICT initiatives, limited expertise and a lack of incentive to use ICTs. High illiteracy levels have been a big hindrance towards successful implementation of the ICT tools especially in rural areas. Many organizations lamented about inadequate knowledge and basic ICT skills, which would allow them to use the tools appropriately, as major obstacles that limit many of the citizens from using the existing ICT tools.
Overall, citizen participation is the most dominant use of ICT tools from the interviews and focus group discussions we conducted. Citizen participation exists in forms such as, using mobile phones to share and receive information with CSOs that run governance programs, toll-free numbers, radio shows, social media platforms by both CSOs and Government ministries and departments. Participation by citizens is in reporting cases of poor management of public resources and sharing opinions on governance issues. Monitoring service delivery by the citizens is especially dominant in areas away from cities. Monitoring service delivery is through using an integration of innovative methods such as using digital cameras for evidence based monitoring, and simple ways such as using SMS to report cases of poor service delivery. Social media is mostly used by organizations interviewed to push out information to citizens with an aim of increasing access and raising awareness. This was particularly prevalent with civil society initiatives targeting youth.
When ICTs for Governance Work:
The cases in which ICTs are successful in promoting citizen participation possess two characteristics:
- Involving low cost and non-Internet based ICTs
- Involving physical meet-up of citizens
Combining two or more ICT tools has proven to enhance two-way interaction between citizens and government.
Ashnah Kalemera, the Programs Associate at the Collaboration on International ICt policy in East and Southern Africa talked about several tools that CIPESA which promotes effective and inclusivity in ICT Policy, Says OpenNet Africa was established in 2012 to monitor internet freedoms in Africa with a primary focus on East and Southern Africa. _URL_ is a centralised platform for information on African internet freedoms and cyber security, including research materials, censorship incidents, laws on internet freedoms, online safety tools and advocacy materials.
OpenNet Africa is driven by a small and dedicated group of individuals who work in partnership with organisations from across the continent and beyond with the shared goal of promoting internet freedom in Africa.
Limitations of ICTs in Governance:
The report highlights the following limitations
- User experience considerations are rarely made when creating ICT tools. In most cases government websites are found to be user-unfriendly.
- "Those websites are ugly, it discourages me from going beyond the home page, so I don't. " – FGD Participant, Nairobi."
- Lack of involvement of citizens (who are the primary target/end users of most of the ICT tools for governance) in the development of ICTs for governance leads to poor prioritization of the citizens' needs. Awareness creation about the existence of these tools, why and how they should be used is not done by the implementers of the tools.
Combining two or more ICT tools has also proven to enhance two-way interaction between citizens and government. In instances where no action is taken after making follow ups, the station publicly calls out the 'culprits' on air to put a spotlight on their failure to take action. This has induced fear among government officials who do not want their corrupt ways made public. When these incidents of corruption are reduced, citizens are motivated to use ICT tools to report corruption, as their contribution does not go in vain.
Despite the investment in ICTs in Governance by the East African governments, evident in the established policies for ICT and e-Government, the implementation of ICT-related projects in governance has not yet been effective in promoting two-way interaction between citizens and governments.
The underlying reason for challenges in implementation of ICTs and ICT initiatives in governance is majorly the design-reality gap yet to be effectively addressed by governance stakeholders. This means that decisions on which ICT tools and initiatives to deploy in governance lies squarely with governments and organizations running the initiatives. Since the initiatives are created for the two-way interaction between citizens and government, more successful implementation would be achieved if citizens were involved in the design process. The design process of applications, which are made for citizens, should involve comprehensive needs assessments and user experience design, which require adequate time and resources. Mobile and web applications that are created or developed in competitions such as tech hackathons do speed up the design process such that within a few days or a few weeks, an app is created. The short time taken to create apps in these hackathons does not allow enough time to involve citizens in the design process; the design-reality gap in these apps is therefore maintained.
Low-cost and non-Internet based ICTs are a natural fit for promoting citizen participation in the East African countries with respect to governance. A big proportion of the East African population lives in rural areas which, as yet, do not enjoy extensive ICT infrastructure as the urban areas do. This therefore makes it imperative that ICT initiatives match the infrastructure available and tech-savviness among citizens in rural areas.
The high investment of ICTs in governance is informed primarily by the potential and promise of their effectiveness in governance. To meet this potential, investment in ICTs for governance needs to shift from developing the ICT tools themselves, to efforts and strategies that reduce the gap between design and implementation of ICT tools and initiatives


text: The most reliable way to support sustainable development is given by creation and implementation of a political strategy. The European Union (EU) has many successful experiences in this field. However, the periodical monitoring reports indicate several important challenges to be met by the EU policy in future. Currently, the EU sustainable development strategy is in progress of being updated and adjusted to new economic, ecological, and social challenges. In this paper, the previous and current achievements in the field of sustainable development policy are analyzed. Further, based on the defined challenges, some recommendations for the future are formulated. The presented investigation shows the necessity of reconsidering some political instruments and practices realized in the past.


Constitution & Bylaws
The name of the society is Canadian Hemochromatosis Society | Société canadienne de l'hémochromatose.
The purposes of the Society are:
a. To promote the awareness and knowledge of hemochromatosis, particularly on the importance of early diagnosis;
b. To provide support, information, encouragement and resources for individuals, families and organizations afflicted by hemochromatosis;
c. To develop partnerships, relations and affiliations that fit the Society's purposes
d. To encourage research on treatment advances and insights into the health economic costs and burden of disease caused by hemochromatosis
e. To liaise with relevant professionals
f. To work with individuals and organizations that complement the Society's purposes
g. To stimulate and support the formation of volunteers;
h. To generate and distribute money and property in the furtherance of the Society's purposes; and
i. To perform such acts and things as are incidental to or necessary for the advancement of the purpose of the Society.
Please click here to view the bylaws (PDF).


TRIVIAL PURSUITS: What is the difference between a green olive and a black olive?
One may think that green and black olives are two different fruits (or vegetables?).
First of all, according to the Oxford dictionary, an olive, just like a plum or a cherry, is a fruit. The olive is the small, bitter-tasting fruit of the olive tree, Olea europea. Olives are classified as fruit because they're formed from the ovary of the olive flower, and they're seed-bearing structures—the pits could grow into trees if you planted them. In culinary terms, however, olives are like those other fruit, tomatoes, and are treated as a vegetable.
Green olives are not from a different tree than black olives, they are just picked before they are ripe.
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Please contact the PLANSPONSOR Reprint Manager, Michelle Judkins.


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I'm having a bit of confusion about how to render text in a pure AS3 project. There are classes like flash.text.StaticText but these are designer-only, you can't create them in code. I was half-expecting the Graphics class to have text-rendering options but alas, no.
Specifically I was going to add a label above each player's sprite with their name, health %, etc. So I expected to add a child text-element or draw text using Graphics in some way... it's read-only and should not support user-input, I just want to draw text on-screen.
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up vote 3 down vote accepted
You can use TextField class for this. Please check the reference. All fields and methods are self explanatory.
A possible example.
var myField:TextField = new TextField();
myField.text = "my text";
myField.x = 200;
myField.y = 200;
addChild(myField); // assuming you are in a container class
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Don't forget selectable = false, it is commonly overlooked. – alxx Feb 4 '11 at 14:38
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text:
Introduction for the Teacher
To prepare yourself spiritually to teach this lesson, please read and ponder the following:
The Holy Ghost is a member of the Godhead, along with Heavenly Father and Jesus Christ. He is a personage of spirit (see D&C 130:22). The mission of the Holy Ghost is to testify of the Father and the Son and of the truth of all things (see 3 Nephi 11:36; Moroni 10:5). He can also guide us to make righteous choices and comfort us (see D&C 31:11). The way the Holy Ghost speaks to us is described in the scriptures as a "still small voice" (see 1 Kings 19:11–12).
Begin with a gathering activity. For ideas, see page 3.
Invite a child to give the opening prayer.
Tell the children that you are going to sing a song about Heavenly Father. Sing or say the words to the first verse of
Invite the children to say "Spirit." Tell them that another name for the Spirit of God is the Holy Ghost. Invite the children to say "Holy Ghost." Explain that the Holy Ghost helps us know that Heavenly Father loves us.
Tell the children that when we do what is right, the Holy Ghost helps us know we made a good choice. Invite the children to join you as you role-play doing things that are right. For example:
It's the right thing to go to church. Let's pretend to walk to church (swing arms as you walk in a circle).
Repeat with other examples, such as sharing a toy, helping Mother sweep the floor, and so on.
Explain that the Holy Ghost can also help us when we are afraid. Tell the following story:
One day there was a bad storm outside David's house. There was loud thunder (have children cover their ears) and lots of wind (have children blow to mimic the wind) and rain (have children mimic the rain with their fingers). David was afraid. His mother told him that when she is afraid she prays to Heavenly Father (show the picture on page 30). David and his mother prayed that Heavenly Father would keep them safe. Then David felt safe and happy. His mother said that Heavenly Father had sent the Holy Ghost to give him those feelings so he wouldn't be afraid.
Invite the children to say "Holy Ghost."
Share your testimony of the Holy Ghost. This could include a simple, brief experience from your own life when you were guided by the Holy Ghost.
Invite a child to give the closing prayer.
For the illustration activity: Copy the illustration on page 31 for each child.
For the cube game: Copy the illustration on page 31 and color it if desired. Cut along the solid lines and fold along the dotted lines. Tape or glue the tabs to make a cube.
Form a circle with the children and recite the following activity verse:
Tell the children that Jesus taught in the scriptures that the Holy Ghost will teach us. Open the Bible to John 14:26 and read, "The Holy Ghost … shall teach you all things." Invite the children to repeat the phrase with you, a few words at a time.
Display the illustration on page 31 and give each child a copy of the illustration. Point to the picture of the Church building and explain that the Holy Ghost helps us know that going to church is the right thing to do. Invite the children to point to the Church building on their copies. Repeat for the other illustrations.
Roll the cube you made. Read the caption on the top of the cube, and have the children repeat it with you. Then have the children do some simple actions to go with the picture. When the side with the words "The Holy Ghost Helps Me" comes up, tell the children that the Holy Ghost helps us know when we've done something good. Repeat, giving each child a turn to roll the cube.


text:
If you want to boil a frog? what you want to do!. Now, You can ask me, Are you mad? Why you want to boil a frog?. Actually not, I am not going to boil any frog in this article but I hope you heard the story called "The Boiling Frog Theory".
The Boiling Frog Theory
"The boiling frog is a fable describing a frog being slowly boiled alive. The premise is that if a frog is put suddenly into boiling water, it will jump out, but if the frog is put in tepid water which is then brought to a boil slowly, it will not perceive the danger and will be cooked to death. "
This theory conveys a little bit of fake information and a lot of real information, In this article, We are going to find out the reality behind the "The Boiling Frog Theory".
How to Boil a Frog?
For example, you want to boil a frog lets boil the water and place the frog inside but the frog will immediately jump out because the water is too hot.- This is the FACT as per the Theory mentioned above.
But, There is a different way to boil a frog, put the frog in warm water then the frog will stay there because it is warm then you slowly increase the temperature of the water. The frog will not notice the small changes in the temperature.
Before the frog completely understands the situation, water will start boiling the frog. finally, the frog will die. This is how you can boil a frog!
This theory reveals the secret of nature and psychology of human. Frogs and Humans notice the big things. When frog knows the boiled water it will jump out like human recognize the disasters like Tsunami, Earthquake, and Strome they stay away from that.
But, Humans fails to notice small changes in people's behavior, price, politics, economy, and climate that finally will kill everyone. you can find this all around us, for example, take a fuel price, it will rise one rupee two rupees every month or week. for now, it's not a big deal for anyone. but over the period of time, this small change will make a big effect in human life without know that the water is boiling. Similarly, your relationship, home rent, and our environment are changing slowly and surely. It is up to us to notice the change and correct us before the water gets fully boiled.
In reality, The frog does aware of the surrounding and it will jump out of the water when it gets too hot. The Boiling Frog Theory was just a popular fable, In reality, frogs can even notice small changes in the surrounding and act according to that change.
If a frog can! Why can't Humans?...
Fix the Small issues before it grows bigger and destroys your life. Think Proactively, Happy Life!!!


text:
Our David and Jean Colker KIDS Program serve children ages 6-13. Meets year-round on weekends and school holidays as well as summer camp. Activities include opportunities to learn age-appropriate safe outdoor travel, computers and other high-tech assistive devices, cooking and self-care techniques, and much more!
School Year Programming
- During the school year, instructors meet with students on school holidays and select weekends. Students are served in a group and/or individual setting, based on their needs. Activities include:
- Opportunities to learn age-appropriate safe outdoor travel
- Braille or use of magnifiers and other low vision devices to assist in reading and writing efficiently
- Computers and other high-tech assistive devices
- Cooking and self-care techniques
- Recreational activities provide the opportunity to interact with other children and successful visually impaired adults who serve as role models.
Family Support Group
All students in The David and Jean Colker KIDS Program and their families are invited to participate in Family Activities throughout the year. The purpose of these events is to allow families to connect with each other, learn more about advocating for their child, and for the whole family to develop techniques to cope with having a child with a visual impairment. Some of the events include:
- Valentine's Party
- Beeping Egg Hunt
- Back to School Bash
- National Blind Sports Day
- White Cane Day
- Fall Festival
- Holiday Party
The David and Jean Colker KIDS Program is a year-round program for children ages 6 through 13. Students attending the camp have to meet the requirements of the program. During the camp, students participate in hands-on:
- STEAM (Science, Technology, Engineering, Art, and Mathematics) activities
- Reading lessons (including Braille and the use of low vision devices)
- Cooking Lessons
- Adapted Sports
Each week, students utilize the skills they are learning to be more independent during field trips. Past field trips have included Science Museums, Water Parks, Tri-Rail trips, Surfing Lessons, and Ropes Course at Broward College.


text:
Amalthaea (ămˌəlthēˈə) [key], in Greek mythology, the stepmother of Zeus, a she-goat or nymph who nursed the infant Zeus. It was said that Zeus made one of her magnificent horns into the cornucopia and set her image among the stars as the star Capella in the constellation Capricorn.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.
More on Amalthaea from Fact Monster:
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Could you tell me if there is any difference in meaning between the following questions?
What do you expect of your partner.
What do you expect from your partner.
For of, I think that this is the most relevant meaning:
typical or characteristic of
For from:
used to show the place where someone or something starts
What you expect of somebody relates to the way they are, and the way that they behave, without reference to your involvement in that behaviour.
What you expect from somebody relates to what you personally get from them, both in terms of material things and their behaviour.
Your Answer


|R'(x)|$ is of the same order as $d (\log \log x)/dx = 1/(x \log x)$, even though $R(x) << \log \log x$. When you compute $N(t) = \int t d(\log \log t)/dt \cdot dt + \int t R'(t) dt$, the two terms are of the same order of magnitude, and you have no control over $N(t)$. – David Speyer May 4 '12 at 17:07
@ David, Thank you for the explanation. Now the gap is clear to me. I have accepted your answer as the answer to this question. – Nilotpal Sinha May 6 '12 at 7:04
Because the scale is too small in Mertens's theorem, and the prime number theorem as well as the Riemann hypothesis are hidden by the $O(1/\log{X})$ notation.
Indeed, the former amounts to strengthening this term to $o(1/\log{X})$; the latter - to $O(1/\sqrt{X})$.
[Incidentally, one could go for equivalent statements to a still smaller scale. Of course, an estimate like $\sum_{p < X} 1/p^2 = \mathrm{const} + O(1/X)$ does not say anything at all about the primes. But one could, if one wished, express the prime number theorem by elaborating on the $O(1/X)$ term. ]
To elaborate on this a bit, let me go to a slightly bigger scale where the prime number theorem begins to emerge outside of $o(1)$. This is also more natural; indeed, it was how Mertens's theorem was proved.
By partial summation, Mertens's estimate is equivalent to $\sum_{p < X} (\log{p})/(p-1) = \log{X} + O(1)$; or, if one prefers, $\sum_{n < X} \Lambda(n)/n = \log{X} + O(1)$. The prime number theorem however is the statement that the $O(1)$ term converges to a constant: $\sum_{n < X} \Lambda(n)/n = \log{X} - \gamma + o(1)$. Indeed, the related bound $\sum_{n < X} \Big( \frac{1}{n} - \frac{1}{X} \Big) \Lambda(n) = \log{X} - 1 - \gamma + o(1)$, another form of the prime number theorem, is what de la Vallee Poussin actually obtained in his original paper. Here $\gamma = 0.57\ldots$ is Euler's constant, but this is of no importance for us, see the next paragraph. Also the $\log{X}$ logarithmic pole corresponds to the pole of $\zeta(s)$ at $s=1$, whereas the $o(1)$ term expresses there being no zeros with $\mathrm{Re}(s) = 1$. The Riemann hypothesis is the correspondingly stronger bound $O(1/\sqrt{X})$ on the $o(1)$ oscillating term. At this scale, in contrast to $\psi(X) = X + O\big( \sqrt{X} (\log{X})^2 \big)$ or $\pi(X) = \mathrm{Li}(X) + O(\sqrt{X}\log{X})$, a logarithmic factor in addition to the square root is not required, as $\sum_{\rho} 1 / |\rho|^2 < \infty$ over the zeros.
Here finally is how to deduce the more usual form $\psi(X) \sim X$ of the prime number theorem from the refinement $S(X) := \sum_{p < X} \Lambda(n)/n = \log{X} -\gamma + o(1)$ of Mertens's theorem: Summing by parts, $\psi(X) = XS(X) - \int_1^X S(t) \, dt = X(\log{X} - \gamma + o(1)) - \big( \int_1^X \log{t} \, dt - \gamma X + o(X) \big) = X + o(X)$.
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Get To Know The Beliefs Of Chinese People When It Comes To Praying
Religion is a topic close to everyone's sentiment; believing in divinity is a very personal issue for every individual. People have their definition when it comes to praying to the deity Jin Paper. Some believe God exists, and others believe that they are just a concept created by humans. But Chinese people have a different take on the aspect of praying to the lord.
Pin on Josh Greco period 1 China
Who does the Chinese believe in?
Most people believe in Buddhism and Daoism; it does not have a strict praying ritual. There are no rigid religious practices; rather, they tend to follow the occasions that help them pray to their gods during those days. Other minorities belong to the Christian religion who regularly meet in the church to pray and have a good time. The other major chunk falls under the criteria of atheism as they do not believe in God, so they generally do not pray.
As there are many people following Buddhism, they indulge in the activity of going to the pilgrimages that many monks follow as the religion can be easily identified with the help of the monks. It is a peaceful religion based on many morals and beliefs, which moulds people into a better human.
Items that help in the process of praying
 - Many items are needed while offering a prayer towards God; these include the religious book with a detailed explanation of how to get involved in the praying act. These books are of immense help to people who have changed their religion or are unsure how to go about it.
 - Chinese people believe in a collective culture, which means that they hold the societal view ultimately rather than focusing on the individuals in the society. So it is essential to follow the mass, and these books are the best aid that can give them a guide when it comes to praying.
 - The Chinese, in their prayers, largely use incense sticks; it refreshes the entire room with a pleasant fragrance. The mellow smell helps calm people as these sticks are burned in a bundle while praying to God, which people traditionally follow. These incense come in different fragrances, so people can opt for whatever smell they like that.
 - It is a large part of their tradition. There are other materials like devotional goods, incense stick holders available in the markets that have a particular shop with the help of which buying these products will be easier. It can be preferable to buy these online as numerous sites allow customers to get the exact products to their home with few clicks. Better quality and a different selection of praying items can be purchased online.
Praying to God gives a peaceful time to oneself to reflect on their thoughts and be calm amidst all the chaos that is going on around the world. Therefore, it is good to remove some time of your day and pray to whoever you believe as it will bring some relief to your mind from all the accumulated stress.


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The Voice
The Voice
by Thomas Hardy
Analysis: Form and Meter
Dactylic Tetrameter Quatrains with Ballad Rhymes (Whew!)
"The Voice" is one crazy-sounding poem, and that's what makes it awesome. There are a few interesting things about the poem's form, and we'll take them one at a time.
First up, we've got ABAB rhymes (also known as ballad rhymes) throughout the poem. Many, though not all, of the poem's rhymes are triple rhymes (in which the last three syllables of the lines rhyme with their partnering lines). For example:
Woman much missed, how you call to me, call to me,A
Saying that now you are not as you were B
When you had changed from the one who was all to me, A
But as at first, when our day was fair. B
The rhymes of lines 1 and 3, of "call to me" and "all to me" are triple rhymes. They sound a bit overdone to us, like the speaker is going over-the-top in his rhyming. Triple rhymes here sound artificial and fake (especially in rhymes like "listlessness and "wistlessness"), and this artificiality jives with one of the big questions of the poem: is the voice real or imagined?
In addition to all of the rhymes at the end of the lines, we've got tons of general sound-y-ness (yes, we just made that word up). There's alliteration in phrases such as "faltering forward" (13) and "thin through the thorn" (14). There's internal rhyme in words such as "you" and "view" (5), and assonance in words such as "mead" and "me" (10).
All of these repeated sounds that exceed the regular rhyme scheme make the poem incredibly dense. The repetitions make us feel like the speaker can't get out of the vicious cycle of grief that he's in. He keeps hearing voices, and he keeps reusing his own vocal patterns. There's no escape from sound in this poem.
The third important thing to know about the poem is its meter (or rhythm). "The Voice" is written in… quatrains (four-line stanzas) of dactylic tetrameter. Wait—don't run away scared! We promise we'll explain!
Dactylic tetrameter means that each line of the poem has four feet (that's the "tetra-" in "tetrameter"), and that each of the poem's feet (which is like a unit of rhythm) is a dactyl. A dactyl is a foot that's made up of a stressed syllable followed by two unstressed syllables. For example, if you say "penalty" out loud, you'll hear a dactyl: DA dum dum. So, when we scan (or figure out the meter of) the first stanza of the poem, we get this pattern:
Saying that now you are not as you were
When you had changed from the one who wasall to me,
But as at first, when our day was fair
The effect of this uncommon meter is a waltzing, lilting feel. It makes us a little dizzy, so don't worry if you're feeling dizzy, too. And what is especially dizzying is that the even-numbered lines are two or three syllables shorter than the odd-numbered lines. The unevenness makes us feeling like we're teetering on a ledge, about to fall over. And in case you haven't noticed, we're in the exact same predicament as the speaker. We're unsure and we've lost our footing—and maybe even our connection to reality. The dizzying form forces us into the position of the speaker. Yikes!
The last important formal thing to think about with "The Voice" is the final stanza of the poem, which shrinks, quite literally. Hardy condenses his weirdo form into something even weirder as he breaks his own patterns. It's almost like the speaker of the poem gives up in the final lines, and he surrenders to the natural sounds of the words, instead of keeping to the strict meter. We read this last stanza as a kind of surrender (both in terms of form and content) to the mysterious voice. The speaker's rhythms no longer matter—it's all about the ghostly voice.
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Baryn Futa encourages a love for the arts
Like any facet of community — roads and infrastructure, community centers, schools, etc. — the arts play a critical role in its contribution to the city's culture. Supporters and benefactors of the fine arts sincerely understand this vital role, including people such as Baryn Futa who personally contribute to this endeavor. Just as the other areas of community deserve widespread support, so do the arts, notes Futa. And, unfortunately, the arts often goes without the support needed. Whether it's individual artists who cannot sustain life within the industry or museums and galleries that lack adequate funding, the arts as a whole suffers and so does its community. Without individuals like Futa who strives to increase arts awareness and love, the arts would flounder. Baryn Futa is determined to spread greater knowledge about their importance and works with others to help artists and art museums grow and thrive.


Impact of taxes on the profitability of projects
China Mining Taxation Workshop – Organised by the Australian Canadian Mining Industry Working Group (ACMIWG), Beijing, China, September 2003
This paper calculates the optimum tax rate for the mining industry.
This study looked at the profitability and level of taxation within the Western World mining industry. Over the 20 year period _PHONE_, the industry only generated an average return of 4.6% to shareholders.
The average tax rate paid by the industry was 39%. This includes corporate taxes and royalties, but excludes indirect taxes. An analysis of the Australian Mining industry shows that these indirect taxes can be very significant – and the overall effective tax rate is 50%.
While the overall returns generated by the mining industry may be low, individual mines may be spectacularly profitable. Indeed, it is the hope of finding such a mine that drives the industry to continue to operate in the face of poor profitability from its existing assets!
Detailed modelling was carried out on the economics of 1000 largest known copper deposits in the world. The aim was to firstly determine how many of these would be built today assuming a given set of tax rules and hurdles. And secondly, if developed, how would the economic benefit be shared between the developer and the government?
Intuitively, if the tax rate is too high, no mines get built and no one benefits. If the tax rate is too low then lots of mines will be built but the Government's revenues may be low (and restricted to the indirect taxes on inputs). But on the other hand, the Government has to provide incentives to industry to find the deposits (and cover the cost of the unsuccessful exploration).
The analysis found that the optimum tax rate depends on the level of business risk. In low-risk countries like Australia the optimum rate is around 50% (which is where the effective tax rate currently is). However, in high-risk countries the optimum rate is 20 – 30%. A key message from this is that High-Risk countries should benchmark their tax rates against their peers rather than against low-risk countries like Australia or Canada.
The paper concludes that there are three actions a Government can do to maximise its return from mining. These are:
 1. Set the tax rate at the right level
 2. Lower the cost of exploration
 3. Lower the level of business risk
The last factor has the largest impact!
Return to Publications


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Leaf curl symptoms that are reminiscent of begomovirus (genus Begomovirus, family Geminiviridae) infection were observed widespread in the tomato crop during the early fall 2005 through the spring 2006 growing seasons in Sinaloa State, Mexico. Symptoms were widespread in three major valleys (Culiacan, Guasave, and Los Mochis) that are largely dedicated to fresh-market tomato production for the U.S. market from October to June. Symptoms included stunting of leaves, shortened internodes, distortion of leaf margins, and green vein banding. Fruit set was reduced significantly (as much as 90%) on the portion of the plant that developed above the point of symptom expression. Tomato fields were heavily infested with the B biotype of the whitefly Bemisia tabaci (Genn.) vector and no other insect vectors were noted in the fields. Total DNA was extracted from six symptomatic tomato plants (two from each valley) and used as template to amplify, clone, and sequence the core region of the begomovirus CP. BLAST analysis of begomovirus sequences available in the NCBI GenBank database indicated the closest match was the Old World monopartite begomovirus Tomato yellow leaf curl virus (TYLCV) from Israel (Accession No. X15656) at 97.8% shared nucleotide (nt) identity. The full-length genome was amplified for each of six isolates using TempliPhi (Amersham Biosciences, Piscataway, NJ) and cloned into the pGEM7 vector (Promega, Madison, WI). The complete DNA genome sequence was determined for eight clones by primer walking. Cloned TempliPhi products sequenced represented two to three isolates from each valley. Results indicated that the isolates (n = 8) were 98.9 to 100% identical (Accession No. DQ631892) to each other, and they shared 98% identity with TYLCV isolates reported from the Caribbean Region and Florida. This highly virulent begomovirus of tomato, originating in Israel, was first reported in Mexico from 1996 to 1997 when it was identified in tomato plants in the Yucatan Peninsula (1) (>1,500 miles from Sinaloa). The latter report followed the introduction of TYLCV in tomato seedlings from Florida into several eastern U.S. states (3,4) and then into Puerto Rico (2). The introduction of TYLCV into Sinaloa where tomato production is highly concentrated is significant because the region supplies the majority (as much as 93%) of fresh-market tomatoes to the western United States from October to June (>$750 million dollars). Of equal importance is the immediate proximity of the pandemic to California where more than 90% of the processing tomatoes in the United States are grown.
References: (1) J. T. Ascencio-Ibáñez et al. Plant Dis. 83:1178, 1999. (2) J. Bird et al. Plant Dis. 85:1028, 2001. (3) M. T. Momol et al. Plant Dis 83:487, 1999. (4) J. E. Polston and P. K. Anderson, Plant Dis. 81:1358, 1997.


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Update: Using LEDs for Instrument Cluster Warning Lights 941046
Traditionally, automotive instrument clusters have been illuminated using incandescent bulbs. Failures of these bulbs are a source of warranty and repair costs. LED lamps can reduce these costs. In addition, LED lamps have a number of other benefits for instrument cluster designs.
This paper describes the design of a hybrid instrument cluster using LED lamps for telltale warning lights and bulbs for gauge lighting. This approach provides a very cost effective design since most telltale warning lights can be illuminated with a single LED. This approach eliminates three quarters of the bulbs in a typical design.
Previous SAE papers, 870211 and 900474, have also discussed the use of LED lamps for telltale lighting. These papers used very specialized lamps. This paper discusses several industry standard LED lamp packages in both through-hole and SMT package configurations. Lighting measurements have been done at instrument cluster depths of 10 to 41 mm, to cover most applications.


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The resultant force acting on an object can cause objects to accelerate or decelerate.
resultant force = mass x acceleration
(newton, N) (kilogram, kg) (metres per second2, m/s2)
The gradient of a distance-time graph represents the speed of the object.
Graph for stationary object.
Graph for a slow moving object (small gradient).
Graph for a fast moving object (steep gradient).
Velocity & Speed
Speed example = 5 m/s
Velocity example = 5 m/s North
A speed only has a size like 20 m/s but a speed in a particular direction like 20 m/s left is called a velocity.
The acceleration of an object is measured in metres/second2 ( m/s2).
acceleration = change in velocity
time taken for change
Graph for object moving a constant velocity.
Graph for object accelerating.
Graph for an object decelerating.
Acceleration for a velocity-time graph
Finding the gradient of a velocity-time graph gives you the acceleration of the object. The greater the gradient the greater the acceleration.
Distance travelled from a velocity-time graph
The distance travelled by an object can be found from the area underneath a velocity-time graph.
The area underneath this graph is a triangle.
The area of a triangle = 0.5 x base x height = 0.5 x 10 x 5 = 25m.
The distance travelled by the object is 25m.


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Hilbert's Building Blocks
Investigating space curves to construct 3-D forms
I have been interested in the area of computer generated forms, mostly
from the architectural viewpoint, for a long time. Most recently I have
been investigating fractals as a way of generating 3-D forms. Not having
a lot of luck in getting results that could suggest reasonable 3-D forms,
I moved back to some earlier work I did in 2-D with Hilbert curves, spirolaterals,
space filling curves, and recursive designs.
The image above on the left is the space filling curve designed by the
German mathematician David Hilbert. The adjacent image shows the three
line segment "generator" for the Hilbert curve. The generator is connected
to another generator by a connecting line segment. By definition, this
type of curve will always remain in a two dimensional plane.
If you break the generator into forward moves and turns, and then modify
the angle of the turn, the lines segments will cross each other. This crossing
enables the curve to trigger a move to another "level". This enables the
determination of the curve height.
Variations can be developed by using a turning angle other than 90 degrees.
Two such variations are shown below.
The second part of the this investigation is the interpretation of the
curve once it is generated. Each of the line segments and their vertices
can be interpreted in three dimensional, architectural terms:
Select one the above variations to view these interpretations individually
and in combination.
walls, each line segment is constructed as a vertical plane
floors, for each set of line segments, the minimum and maximum extends
are found and constructed into a horizontal plane
floor blocks, the horizontal floor plane is constructed into a volume
extended walls, walls are constructed from the bottom and the top,
starting at their beginning level, extending either to the bottom or top
columns, volumes are constructed at the vertices of the line segments
and the floor blocks
beams, volumes are constructed along each line segment at the wall
The more I worked with these variations and their interpretations, the
more sculptural the forms became, further studies will continue in both
the sculptural and architectural form possibilities.
The next set of forms will use spirolaterals and more generalized recursive
curves for the initial form generation.
The forms currently only exist in this digital studio. My next goal
is to generate STL files of the forms to send to a rapid prototyping system.
Another possible direction would be to rewrite the generation software
in AutoLisp for use within AutoCAD R13. This would also allow for the automation
of the rendering of each variation.
The entire idea of generating forms from specifications, have software
develop alternative interpretative forms, then going to physical models
is very intriguing; these concepts will continue to be the general direction
of this investigation.
A program written in MicroSoft QuickBASIC is used to generate all of the
three dimensional components required for a particular variation in a 3D
DXF format. The DXF file is then imported into AutoDesk 3D Studio for rendering.
No manual modeling is required.
These Web pages were constructed for use with Netscape 1.1.
The initial programs which I wrote for the two dimensional versions and
interpretations were upgraded to handle three dimensions by Amy Ferguson,
a Teaching Assistant in the College of Architecture. She also did some
exhaustive studies of the variations possible and some of the studies leading
to the renderings produced here.
For further information or comment contact: Robert
Last update: Friday, December 29, 1995
Copyright 1995 Robert J. Krawczyk All Rights Reserved


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Baseodiscus princeps (Coe, 1901)
|Baseodiscus princeps from March Point, Padilla Bay, WA|
|(Photo by: Dave Cowles, July 2007)|
How to Distinguish from Similar Species: Tubulanus polymorphus is also uniformly orange or reddish but it has no eyespots nor anteroventral grooves. The description of this species sounds very much like that of B. punnetti from farther south.
History: The animal
is able to contract its body in such a way as to form annular regular
along the body (photo).
It can contract its head entirely into its trunk.
|Main Page||Alphabetic Index||Systematic Index||Glossary|
General Notes and Observations: Locations, abundances, unusual behaviors:
The head is lighter dorsally than is the rest of the dorsum, and has a line of dark eyespots around the border.
The underside is lighter than the dorsum, as seen in this view of an upraised head.
The animal can constrict its muscles to form annular constrictions.


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You can create or configure Resource Governor entities, such as resource pools and workload groups, by using the Resource Governor Properties page in SQL Server Management Studio.
In addition to viewing the properties of Resource Governor entities, you can perform several configuration tasks using the Resource Governor Properties page. For more information, see these topics:
When you click OK after adding, deleting, or moving a workload group or resource pool, the ALTER RESOURCE GOVERNOR RECONFIGURE statement is executed.
If the create or reconfigure operation for the resource pool or workload group fails, a summary error message appears below the title of the property page. To see a detailed error message, click the down arrow on the error message.
You can determine whether there is a configuration pending by querying the sys.dm_resource_governor_configuration dynamic management view to get the current status of is_configuration_pending.
Viewing resource governor properties requires VIEW SERVER STATER permission. The resource governor configuration tasks require CONTROL SERVER permission.
To view resource governor properties by using the Resource Governor Properties page in SQL Server Management Studio
In SQL Server Management Studio, open Object Explorer and recursively expand the Management node down to Resource Governor.
Right-click Resource Governor and then click Properties, this opens the Resource Governor Properties page.
For descriptions of the fields in the page, see Resource Governor Properties.
To save any changes, click OK.
Classifier function name
Specify the classifier function by selecting from the list.
Enable Resource Governor
Enable or disable Resource Governor by selecting or clearing the check box.
Create or change resource pool and external resource pool configuration by using the grid that is provided. This grid is populated with information for the predefined internal and default pools. Select a pool to work with by clicking the first column in the row for the pool. To create a new resource pool, click the row that is prefixed by the asterisk (\*).
Specify the name of the resource pool.
Minimum CPU %
Specify the guaranteed average CPU bandwidth for all requests in the resource pool when there is CPU contention. Range is 0 to 100.
Maximum CPU %
Specify the maximum average CPU bandwidth that all requests in this resource pool will receive when there is CPU contention. Range is 0 to 100. The default setting is 100.
Minimum Memory %
Specify the minimum amount of memory reserved for this resource pool that can not be shared with other resource pools. Range is 0 to 100.
Maximum Memory %
Specify the total server memory that can be used by requests in this resource pool. Range is 0 to 100. The default setting is 100.
Workload groups for resource pool
Create or change the workload group configuration by using the grid that is provided. This grid is populated with information for the predefined internal and default groups. Select a group to work with by clicking the first column in the row for the pool. To create a new workload group, click the row that is prefixed by the asterisk (\*).
Specify the name of the workload group.
Specify the relative importance of a request in the workload group. Available settings are Low, Medium, and High.
Specify the maximum number of simultaneous requests that are allowed to execute in the workload group. Must be 0 or a positive integer.
CPU Time (sec)
Specify the maximum amount of CPU time that a request can use. Must be 0 or a positive integer. If 0, the time is unlimited.
Memory Grant %
Specify the maximum amount of memory that a single request can take from the pool. Range is 0 to 100.
Grant Time-out (sec)
Specify the maximum time that a query can wait for a resource to become available before the query fails. Must be 0 or a positive integer.
Degree of Parallelism
Specify the maximum degree of parallelism (DOP) for parallel requests. Range is 0 to 64.
For more information, see CREATE WORKLOAD GROUP (Transact-SQL).
View Resource Governor properties using Transact-SQL
View resource governor properties by using Transact-SQL
To view the definitions of resource governor entities, use the Resource Governor Catalog Views (Transact-SQL).
To view the current configuration of resource governor entities, use the Resource Governor Related Dynamic Management Views (Transact-SQL).


text:
Effects of "Bath Salts" on the Brain are Comparable to Cocaine, Rodent Study Suggests
A new rodent study suggests that a key ingredient in "bath salts" called mephedrone has effects on the brain's reward circuits that are comparable to similar doses of cocaine. The study offers evidence that mephedrone has the potential for abuse and addiction, the researchers say.
Dr. C.J. Malanga of the University of North Carolina School of Medicine studied mice implanted with electrodes that stimulate the brain. They were trained to spin a wheel to receive a reward, which directly stimulated the brain pathways involved in reward perception, according to UPI. The mice were given various doses of either mephedrone or cocaine. Their wheel spinning was measured before, during and after they received the drugs.
The study found the effects of mephedrone on the reward circuits in the brain were similar to those of cocaine. "As expected our research shows that mephedrone likely has significant abuse liability," Dr. Malanga said in a news release.
The study appears in the journal Behavioural Brain Research.


text:
- of or resembling a tooth; toothlike.
Origin of odontoid
Examples from the Web for odontoid
Historical Examples of odontoid
The first vertebra has nothing of the nature of an odontoid process.The Vertebrate Skeleton
Sidney H. Reynolds
The odontoid process of the axis is still more concave than in Poebrotherium, but not spout-like as in existing forms.
The odontoid process of the axis vertebra is somewhat cheese-taster shaped, as in recent Artiodactyles.
Odontoid process of second vertebra semi-cylindrical; skull with a sagittal crest; and the condyle of the lower jaw rounded.
Change of form of the odontoid process of the second or axis vertebrae from a cone to a hollow half-cylinder.
- of or relating to the odontoid process
- Shaped like a tooth.
- Of or relating to the odontoid process.


text:
ALL Ohio (Advancing Literacy Learning in Ohio) is a compilation of high-quality professional learning resources for Ohio's P20 education system. ALL Ohio serves as a tool to strengthen educators' knowledge and skills in evidence-based language and literacy practices grounded in the science of reading.
The ALL Ohio Literacy Library is a repository of high-quality, open-access learning modules for educators, families, and community members to enhance the literacy learning of all children and youth. The ALL Ohio learning modules explore various literacy topics in-depth through narrative text, linked resources, realistic scenarios, reflections, learning activities, and embedded audio and videos. Upon successful completion of a module, educators can earn a proficiency-based micro credential that they can submit to the their provider for continuing education credit.
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text:
How The Kumbh Mela Crowds Are Counted
Date 2013/2/7 18:04:40 | Topic: Hindu Press International
ALLAHABAD, INDIA, February 2, 2013 (India Real Time): The Kumbh Mela is frequently billed as the world's largest religious gathering. It is almost certainly true. But how can we know for sure? The two men with the challenge of counting up to an estimated 80 million people are divided on how to do it. They also come up with different numbers. They are Devesh Chaturvedi, the commissioner of Allahabad, and Alok Sharma, the inspector general of police in the city, which is hosting the Hindu festival.
The Commissioner reckons the number of pilgrims passing through the Kumbh Mela site on the banks of the Ganga between Jan. 14 and March 10 will end up somewhere between 60 to 80 million. Both men use different techniques for counting but agree neither method is scientific or water tight. Mr. Sharma is more conservative and estimates the final total will be around 40 to 60 million.
"We use thumb rules," says Mr. Sharma. His team positions counters at the entry points to the Mela area, which leads to the bathing ghats (banks). They calculate the maximum crowd capacity of 100 meters of road based on the assumption that each pilgrim will take up 1.5 square feet of ground. Then they measure the speed of the crowd by timing how long it takes a police officer to move 600 meters with the throng. "The pace of crowd keeps changing depending on the density," the Inspector General adds. Once they know how long it has taken the policeman to walk 600 meters they can work out how big a crowd has covered the same distance and how many people have passed. Vehicles arriving along the entry roads around Allahabad are counted manually and trains with up to 8,000 passengers each are also added to the total.
Mr. Chaturvedi has a different approach to the enormous population count. From a series of watch towers across the 14 sectors of the Mela site head-counters try to keep a tab on the number of pilgrims below. "It's not the most scientific way of doing it," Mr Chaturvedi says. "But that is the only estimate available to us." This year for the first time the Mela is also being tracked using satellite imagery. "Based on the color of the images they are going to tell what is the density of human beings," Mr. Chaturvedi says. Using calculations based on the average stay of pilgrims and photographs taken at different times of day, the Commissioner hopes it will provide a more accurate count.
Mr. Chaturvedi says that the biggest crowd so far, on the first day of the festival, was 8 million while Mr. Sharma puts it at between 1.5 million and 1.8 million.


text:
Published on May 10, 2012 at 5:06 AM
Soybeans soaking in warm water could become a new "green" source for production of a cancer-fighting substance now manufactured in a complicated and time-consuming industrial process, scientists are reporting in ACS' Journal of Agricultural and Food Chemistry.
Hari B. Krishnan and colleagues explain that the substance, Bowman-Birk Protease Inhibitor (BBI), has shown promise for preventing certain forms of cancer in clinical trials. Those human tests resulted from evidence of BBI's beneficial effects, including indications that BBI derived from the large amounts of soybeans in traditional Japanese diets might underpin low cancer mortality rates in Japan. However, the current method of extracting BBI from soybeans is time-consuming and involves harsh chemicals. The scientists set out to see if there might be a greener and more environmentally friendly way of obtaining BBI.
They found that soybean seeds incubated in water at 122 degrees Fahrenheit naturally release large amounts of BBI that can easily be harvested from the water. The protein appeared to be active, with tests showing that it stopped breast cancer cells from dividing in a laboratory dish. "The abundance of BBI in soybean seed exudates by incubating the seeds in warm water provides a simple and alternative method to isolate this low molecular weight protein," the researchers said.
Source: American Chemical Society


text:
Composition of Solutions
Problems and Solutions
Calculate the volume of a 0.753 M sodium hydroxide solution that is neutralized by the addition of 100 mL of a 1.203 M sulfuric acid solution.
If the volume of a 100 L solution of 1.1 moles of hydrogen in 6.0 moles argon is suddenly doubled, what happens to the mole fraction of hydrogen in that solution?
What is the concentration of HCl stock solution that can create 250 mL of a 1.0 M solution that is prepared by the dilution of 50 mL of the HCl stock solution?


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|Freshwater Mussels of the Upper Mississippi River System|
Mussel Conservation Activities
2005 Highlights: Possible fish predation of subadult Higgins eye was observed in the Upper Mississippi River, Pools 2 and 4.
Subadult Higgins eye pearlymussels (Lampsilis higginsii) from the Upper Mississippi River, Pools 2 and 4. Shell damage may be due to predation by fish (i.e. common carp or freshwater drum). Top photo by Mike Davis, Minnesota Department of Natural Resources; bottom photo by Gary Wege, U.S. Fish and Wildlife Service.
Species Identification and Location • Threatened and Endangered Mussels • Life History • Ecology • Mussel Harvest on the River • Current Threats • Mussel Conservation Activities • Ongoing Studies and Projects • Multimedia • Teacher Resources • Frequently Asked Questions • Glossary • References • Links to Other Mussel Sites
Privacy • FOIA • FirstGov • Contact
Department of the Interior • U.S. Fish & Wildlife Service • U.S. Geological Survey
|Last updated on
December 21, 2006


Mobility Investigate
Finding Links and Initiators: A Graph-Reconstruction Problem
Download now Free registration required
Executive Summary
Analyzing 0-1 matrices is one of the main themes in data mining. Techniques such as clustering or mixture modelling, matrix decomposition techniques such as PCA, ICA, and NMR, and Bayesian all aim to give an answer to the informal question: "Where does the matrix come from?" These approaches aim at describing a probabilistic generative model that describes the observed matrix well. This paper considers yet another way of answering the question "Where does a 0{1 matrix M come from?" In the model, the matrix M of size n? m is considered to arise from initiators, certain few entries that are initially 1.
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Does your child have difficulty with activities that require coordination and balance? Do they often bump into things or are "clumsy" in general? It may be because of today's reflex: The Tonic Labyrinthine Reflex! This reflex helps a child build their core muscles and is part of the reason why tummy time is so important! Without enough tummy time, some children will retain this reflex instead of integrating it and will have trouble with coordination and spatial awareness especially! They may also have a hard time with sequencing activities, like telling a story in order, or memorizing things like the days of the week, the alphabet in the right order, and organizing things into the right categories. Retaining this reflex also causes poor core stability and so these kids may have trouble with posture and balance.
So, what if your child still has this reflex? Did you know you can FIX this? It's easy and fun with our primitive reflex exercises! If you're interested in learning more, check out our parent workshops! We'd love to help!


Xiaolin Huang Ph.D.
Pattern Recognition Methods for Medical Image Processing
Applications of Piecewise Linear Technology
The applications of machine learning methods on medical engineering have attracted lots of attention. In this research, we focus on piecewise linear technology in machine learning and its application on medical image/signal processing for noise, outliers, and large-scale data. Piecewise linear functions are the simplest extension to linear functions. On the one hand, piecewise linear functions can be analyzed and solved as a series of linear systems. On the other hand, a piecewise linear function is nonlinear on the whole and we can design a suitable one for desired properties. In this project, we will further analyze the properties, develop efficient algorithms, and then apply them in medical engineering.
This project is supported by the Alexander von Humboldt Foundation.


text:
U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
Federal Highway Administration Research and Technology
Coordinating, Developing, and Delivering Highway Transportation Innovations
|This fact sheet is an archived publication and may contain dated technical, contact, and link information|
|Publication Number: FHWA-HRT-13-095 Date: September 2013|
Publication Number: FHWA-HRT-13-095
Date: September 2013
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Long-distance trips in the United States can take 2 days or 2 weeks and may involve cars, buses, planes, or all three. Whether for business, to see family, or visit a national park, such a variety of trip characteristics requires a detailed understanding of traveler needs. Exploring new ways to model long-distance traveler behavior and better identify the required supporting infrastructure is the goal of "Foundational Knowledge to Support a Long-Distance Passenger Travel Demand Modeling Framework," a Federal Highway Administration (FHWA) Exploratory Advanced Research (EAR) Program study awarded to Resource Systems Group (RSG).
Highway infrastructure planning, high-speed rail development, and airport growth all depend on long-distance travel markets. To ensure infrastructure can meet growing demands in these areas there is a need to model and analyze passenger behavior. Interest in long-distance passenger modeling for statewide models has already been seen in California, Ohio, and Arizona, and high-speed rail studies have been conducted in Florida, California, and the Northeast Corridor; however, these models have been based on traditional travel demand forecasting methods rather than a robust understanding of underlying behavior and how and why long-distance passenger movements differ from other passenger travel.
Long-distance travel behavior will be explored in several key areas that move beyond traditional methods used for existing statewide models. For example, long-distance trips are scheduled weeks or months in advance of the trip and typically last several days or weeks. There are also significant seasonal effects that can influence long-distance travel, unlike short-distance travel which remains similar day-to-day. Both leisure and business travel are more sensitive to changes in the economy than short-distance travel and leisure activities will often differ from business activities as they are planned and executed with different goals and choices. Party size can also have a significant effect on mode and destination choices.
Several observations have been made based on current modeling techniques. Recreational travel models typically adopt a similar structure to business and other travel, despite broad differences between the two. Business models are generally more time-sensitive and less concerned with party size as a mode choice variable when compared to recreational travel models. For example, a business traveler on a long-distance trip is more likely to fly regardless of expense or the number of colleagues traveling in the party. A family on vacation, however, may decide to drive to save money even if the trip takes longer. Although advanced integrated activity-based models are currently operational, these are limited to an estimate of average weekday travel and do not account for scheduling, influence of other trips, other travelers, or social character.
An additional challenge is that no single dataset offers all the required features for estimating and applying long-distance travel demand forecasting models in the United States. A series of datasets have been identified for exploring long-distance models and the results will be a modeling framework that can be re-estimated once national long-distance travel data become available. The research team will use their experience to bridge the gap between ideal modeling design and implementing a tool that will be of practical use to planners.
The ultimate goal of this study is to explore new approaches for a national model that is estimated, calibrated, and validated on available long-distance travel data in the United States and can subsequently be updated with new long-distance travel data for use in planning applications around the country. In the short term, this project will examine possible new frameworks for a national model that identify specifications based on statistical analysis of available data.
"The framework being developed can provide a foundation for subsequent implementation of an innovative national passenger forecasting model," said Brad Gudzinas at FHWA. "The products of this research are first steps toward providing the tools needed to identify significant future travel trends and, ultimately, to make more informed decisions about policy and infrastructure investments," he added.
For more information on this EAR Program project,contact Brad Gudzinas, FHWA Office of Highway Policy Information, at _PHONE_ (email: _EMAIL_)..
What Is the Exploratory Advanced Research Program?
FHWA's Exploratory Advanced Research (EAR) Program focuses on long-term, high-risk research with a high payoff potential. The program addresses underlying gaps faced by applied highway research programs, anticipates emerging issues with national implications, and reflects broad transportation industry goals and objectives.
To learn more about the EAR Program, visit the Exploratory Advanced Research Web site at _URL_ The site features information on research solicitations, updates on ongoing research, links to published materials, summaries of past EAR Program events, and details on upcoming events. For additional information, contact David Kuehn at FHWA, _PHONE_ (email: _EMAIL_), or Terry Halkyard at FHWA, _PHONE_ (email: _EMAIL_).


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- UCAR Home
- About Us
- For Staff
IMAGe GSP Brown Bag Seminar (Bring your lunch)
Johannes Werner (TU Darmstadt) and Susan Tolwinski-Ward (NCAR)
May 22 at 12:00
Location: ML Penthouse on tower B
During the last years, new and improved climate reconstructions of the pre-instrumental period have become available. They usually focus on one variable of interest only, regressing e.g. temperature on tree ring growth. However, most of the climate archives respond to more than one climate variable and limited tree growth could be caused by colder than normal temperatures as well as too dry conditions. We know from documentary data that in Central Europe the year 1540 was extremely hot, still it does not show up as an extreme year in the tree ring based reconstructions - likely because tree growth was limited by the drought beginning in 1539.
The aim of our project is to integrate both documentary evidence and tree ring data of 1540 into a joint reconstruction targeting moisture and temperature over the Western Alps, using suitable statistical descriptions: VS-Lite for the tree growth and a multinomial model for the documentary data. These models are then combined with a process level model over the instrumental period. The use of different climate archives and the extension to two variables of interest should improve future climate reconstructions.


The effect of Mg on Ca movement between the sarcoplasmic reticulum (SR) and myofilament space (MFS) was studied in skinned muscle fibers by using isometric force as an indicator of MFS Ca. In Ca-loaded fibers at 20 degrees C, the large force spike induced by Ca in 1 mM Mg (5 mM ATP) was strongly inhibited in 3 mM Mg, and force development was extremely slow. After a brief Ca stimulus in 1 mM Mg, relaxation in Ca-free solution was significantly faster in 3 mM Mg. These changes were due to altered Ca movements, since the effect of 3 mM Mg on steady force in CaEGTA solutions was small. Changes in Mg alone induced force transients apparently due to altered Ca movement. In relaxed fibers, decreasing the Mg to 0.25 mM caused phasic force development. In contracting fibers in Ca solutions, increasing the Mg caused a large transient relaxation. The effects of increased Mg were antagonized by 0.5 mM Cd, an inhibitor of the SR Ca transport system. The results indicate that active Ca uptake by the SR in situ is stimulated by Mg, and that it can affect local MFS [Ca++] in the presence of a substantial Ca source. These results provide evidence that an increased rate of Ca uptake in 3 mM Mg could account for inhibition of the large force spike associated with Ca-induced Ca release in skinned fibers.
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May 24, 2004 PROVIDENCE, R.I. -- Male bullfrogs communicate with other bullfrogs through calls made up of a series of croaks, some of which contain stutters, according to a new Brown University study which describes a pattern not previously identified in scientific literature.
Researchers recorded 2,536 calls from 32 male bullfrogs in natural chorus and analyzed the number of croaks in each call and the number of stutters in each croak. It is known that the male bullfrog's call attracts females for mating, maintains territorial boundaries with other males, and indicates that the frog is healthy and aggressive.
"Some animals have evolved large, complex vocabularies to communicate, while others say a lot with very limited numbers of calls," said Andrea Simmons, professor of psychology, who presented the findings at 75th meeting of the Acoustical Society of America Monday, May 24, 2004. "A fundamental question in the study of communication by sound is 'how much information can a sender convey in a single sound'?"
Within a single vocalization, the frogs exhibited a pattern of croaks with and without stutters that appeared to have a communication function and did not simply represent that a male was getting tired, Simmons said.
An acoustic analysis showed the stutters followed certain rules: 100 percent of the recorded calls began with a croak containing no stutters; when the frogs started stuttering they generally did so within a croak that contained one stutter only; when they increased or decreased stutters from croak-to-croak, they did so by only a single stutter.
Stuttering did not occur because a frog was "running out of breath," said the researchers. If that were the case, a less structured pattern of stutters would occur. More likely, the frog inserted stutters in the call to extend the length of his individual calls while reducing the amount of air exchange needed, similar to what occurs when opera singers insert vibrato in extended notes.
To determine how the frog's calls were perceived, researchers played pre-recorded stuttering and non-stuttering calls through a loudspeaker to individual males. The frogs appeared to use non-stuttered calls for aggressive or territorial purposes. Males produced the stuttered calls more frequently at certain points during the breeding season, indicating the stuttering may be involved in attracting a mate.
Simmons conducted the study with Dianne Suggs, a graduating senior in psychology, who used it as the basis of her undergraduate honors thesis. Suggs was supported by a grant through the Undergraduate Teaching and Research Assistantship (UTRA) program. Simmons' laboratory is supported by a research grant from the National Institutes of Health.
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Moby-Dick Chapter 108: Ahab and the Carpenter Summary
- The novel returns to a playbook-style format with stage directions.
- In the evening, the carpenter is working on Ahab's new ivory leg by lantern-light.
- The blacksmith is working, too, in the background.
- The carpenter murmurs to himself about the leg as he works on it.
- Ahab visits the carpenter so the length of the leg can be measured.
- He asks the carpenter what the blacksmith is doing, and the carpenter explains that the blacksmith is making the buckle-screw.
- Ahab describes the blacksmith as a second Prometheus, and jokes that he's going to order him to forge a completely mechanical man.
- Ahab begins to talk to about creation, and the carpenter doesn't know whether he's talking to himself or not.
- Then Ahab asks the carpenter if, in addition to making the new bone leg, he can make Ahab stop feeling the old leg in its place, which, of course, he can't.
- Ahab laments the fact that he must depend on the carpenter's help, when he'd rather feel himself entirely free and independent.
- The carpenter resumes his work, reminding himself that Stubb always calls Ahab "queer" and feeling the truth of that label.
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1 blocks are used to train the model. The held out block is predicted and these predictions are summarized into some type of performance measure (e.g. accuracy, root mean squared error (RMSE), etc.). The kk estimates of performance are averaged to get the overall resampled estimate. kk is 1010 or sometimes 55. Why? I have no idea. When kk is equal to the sample size, this procedure is known as Leave-One-Out CV.
 - Repeated k-fold CV does the same as above but more than once. For example, five repeats of 10-fold CV would give 50 total resamples that are averaged. Note this is not the same as 50-fold CV.
 - Leave Group Out cross-validation (LGOCV), aka Monte Carlo CV, randomly leaves out some set percentage of the data BB times. It is similar to min-training and hold-out splits but only uses the training set.
 - The bootstrap takes a random sample with replacement from the training set BB times. Since the sampling is with replacement, there is a very strong likelihood that some training set samples will be represented more than once. As a consequence of this, some training set data points will not be contained in the bootstrap sample. The model is trained on the bootstrap sample and those data points not in that sample are predicted as hold-outs.
What are point estimation and function estimation in the context of Machine Learning? What is the relation between them?
Point estimation refers to obtaining estimates for specific data points (such as estimating yy from xx, or estimating yy from a distribution). In machine learning, this is the main prediction task. Machine learning models do this by approximating the function that maps xx to yy. I.e., a model approximates the function f(x)=yf(x) = y
What is the maximal likelihood of a parameter vector θ\theta? Where does the log come from?
The MLE for a vector parameter θ=[θ1,θ2,...,θp]T\theta = [\theta_1, \theta_2,..., \theta_p]^T is defined as the value that maximizes the likelihood function p(x;θ)p(x; \theta), i.e.,
θ^ML=argmaxθp(x;θ)\hat{\theta}_{\text{ML}} = \text{arg}\max_{\theta} p(x; \theta)
In practise the MLE is found from the root of the log-likelihood function lnθ=0\frac{\partial \ln}{\partial \theta}=0
If multiple solutions exist, then the one that maximizes the likelihood function is the MLE.
Prove that for linear regression MSE can be derived from maximal likelihood by proper assumptions.
Probabilistic assumption:
Assume that the target variables and the inputs are related via the equation:y(i)=θTx(i)+ϵ(i)y(i)= \theta Tx(i)+ \epsilon(i)
where ϵ(i)\epsilon^{(i)} is an error term that captures either unmodeled effects (such as if there are some features very pertinent to predicting housing price, but that we'd left out of the regression), or random noise.
Assume ϵ(i)\epsilon^{(i)} are distributed IID (independently and identically distributed) according to a Gaussian distribution (also called a Normal distribution) mean zero and some variance σ2\sigma^2
The density of ϵ(i)\epsilon^{(i)} is: p(ϵ(i))=12πσexp((ϵ(i))22σ2)p(\epsilon^{(i)})=\frac{1}{\sqrt{2\pi}\sigma}\exp \left(-\frac{(\epsilon^{(i)})^2}{2\sigma^2}\right)
This implies that: p(y(i)x(i);θ)=12πσexp((y(i)θTx(i))22σ2)p(y^{(i)}|x^{(i)};\theta)=\frac{1}{\sqrt{2\pi}\sigma}\exp \left(-\frac{(y^{(i)}-\theta^Tx^{(i)})^2}{2\sigma^2}\right)
Likelihood function: L(θ)=L(θX,y)=p(yX;θ)L(\theta)=L(\theta|\mathbf{X},\mathbf{y})=p(\mathbf{y}|\mathbf{X};\theta)
p(yX;θ)p(y|X;\theta): This quantity is typically viewed a function of yy (and perhaps XX), for a fixed value of θ\theta.
By the independence assumption on the ϵ(i)\epsilon^{(i)}'s (and hence also the y(i)y(i)'s given the x(i)x(i)'s), this can also be written:
L(θ)=i=1np(y(i)x(i);θ)=i=1n12πσexp((y(i)θTx(i))22σ2)L(\theta)= \prod_{i=1}^n p(y^{(i)}|x^{(i)};\theta) \\ =\prod_{i=1}^n \frac{1}{\sqrt{2\pi}\sigma}\exp \left(-\frac{(y^{(i)}-\theta^Tx^{(i)})^2}{2\sigma^2}\right)
The principal of maximum likelihood says that we should choose θ\theta so as to make the data as high probability as possible \rightarrow maximize L(θ)L(\theta).
Instead of maximizing L(θ)L(\theta), we can also maximize any strictly increasing function of L(θ)L(\theta) \rightarrow log likelihood (θ)\ell(\theta):
(θ)=logL(θ)=logi=1np(y(i)x(i);θ)=i=1nlog12πσexp((y(i)θTx(i))22σ2)=nlog12πσ12σ2i=1n(y(i)θTx(i))2\ell(\theta)=\log L(\theta)=\log \prod_{i=1}^n p(y^{(i)}|x^{(i)};\theta) \\ =\sum_{i=1}^n \log \frac{1}{\sqrt{2\pi}\sigma}\exp \left(-\frac{(y^{(i)}-\theta^Tx^{(i)})^2}{2\sigma^2}\right) \\ = n\log\frac{1}{\sqrt{2\pi}\sigma}-\frac{1}{2\sigma^2} \sum_{i=1}^n (y^{(i)}-\theta^Tx^{(i)})^2
Hence, maximizing (θ)\ell(\theta) gives the same answer as minimizing
To summarize: Under the previous probabilistic assumptions on the data, least-squares regression corresponds to finding the maximum likelihood estimate of θ\theta. Note also that, in our previous discussion, our final choice of θ\theta did not depend on what was σ2\sigma^2, and indeed we'd have arrived at the same result even if σ2\sigma^2 were unknown.
Why is maximal likelihood the preferred estimator in ML?
The main appeal of the maximum likelihood estimator is that it can be shown to be the best estimator asymptotically, as the number of examples mm \rightarrow \infty, in terms of its rate of convergence as mm increases
Under appropriate conditions, the maximum likelihood estimator has the properties of:
 - consistency: as the number of training examples approaches infinity, the maximum likelihood estimate of a parameter converges to the true value of the parameter. θ^θn\hat{\theta} \rightarrow \theta^{n \rightarrow \infty}.
 - efficiency: the Cramér-Rao lower bound (Rao, 1945; Cramér, 1946) shows that no consistent estimator has a lower mean squared error Var(θn)\text{Var}(\theta^n) than the maximum likelihood estimator
When the number of examples is small enough to yield overfitting behavior, regularization strategies such as weight decay may be used to obtain a biased version of maximum likelihood that has less variance when training data is limited.
Under what conditions do the maximal likelihood estimator guarantee consistency?
There are two conditions:
Condition #1: The true distribution pdatap_{\text{data}} must lie within the model family pmodel(;θ)p_{\text{model}}(·; \theta). Otherwise, no estimator can recover pdatap_{\text{data}}.
Condition #2: The true distribution pdatap_{\text{data}} must correspond to exactly one value of θ\theta. Otherwise, maximum likelihood can recover the correct pdatap_{\text{data}}, but will not be able to determine which value of θ\theta was used by the data generating processing.
What is cross-entropy loss?
Cross-entropy loss, or log loss, measures the performance of a classification model whose output is a probability value between 0 and 1. Cross-entropy loss increases as the predicted probability diverges from the actual label. So predicting a probability of.012 when the actual observation label is 1 would be bad and result in a high loss value. A perfect model would have a log loss of 0.
Cross-entropy and log loss are slightly different depending on context, but in machine learning when calculating error rates between 0 and 1 they resolve to the same thing.
def CrossEntropy(yHat, y):
 if y == 1:
 return -log(yHat)
 return -log(1 - y


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Find a relationship between x and y such that (x,y) is equidistant from the two points.
(3,-2) and (-7, 1)
To solve this equation:
- Square both sides of the equation
- Use subtraction to get both of the y terms on one side and both of the x terms on the other
- Expand the squares and simplify
- Solve for y in terms of x
Check your answer against (-2, -0.5) -- the exact values, obtained by the midpoint formula --by plugging them into the resulting function.
You are correct. There is an alternative, simpler and easier way to do this btw:
1. Using midpoint formula, find the point that is equidistant between these two points is:
2. Find the slope of the two given points. (-3/10)
3. Take the negative reciprocal of the slope (10/3).
4. Plug in point-slope form (Use the negative reciprocal slope and the point we got from midpoint formula):
y - y1 = m(x - x1)
There, you got yourself the equation for a line that is perpendicular to the midpoint.
You could have used the construction of the perpendicular bisector to verify your answer. Working it two ways and getting the same answer is a great confidence builder. Too bad Chop Suey did it for you. You missed a great opportunity to explore and to learn. Don't let the next opportunity get by you.


How Deep Should A Pond Be For Koi Fish?
Koi have to be one of the most popular, if not THE most popular species of fish we keep outdoors. A fact that is pretty unsurprising really when you consider their majestic size, bright colors, and absolute confidence around humans. They make fabulous pets that can live for up to 30 years and really make themselves part of the family.
A koi pond should be at least 3-4 feet deep to protect your fish from freezing through winter. This will also to ensure you have enough water volume to cope with all the waste that Koi produce. A minimum of 1000 Gallons in total is a minimum water volume you'll need to keep koi carp.
The chances are that if you are considering keeping Koi you'll need to start from scratch in your preparation for owning them. This includes building them a pond! Few homes, come with a pond already in the garden, and even if there is one, it may not be suitable for Koi. You see, Koi ponds have some specific requirements which the most important of is depth.
koi fish
How Deep Should A Pond Be For Koi?
Koi, when fully grown, are an incredibly large species that can reach up to 24 inches (60 cm) in size. This is easily forgotten when you view or purchase the 3 to 4-inch specimens at your local aquatic store. That means that often pond size and depth for this aquatic giant is underestimated. This can lead to future problems (which we'll cover shortly) with their care.
It is recommended that a Koi pond should be at least 4 feet deep (1.2 meters) with the mantra being 'the deeper the better'. It should also cover an area of at least 8 by 6 foot and hold 1000 gallons of water minimum.
As a rough guide for this size pond, you could house 4 to 5 fully grown Koi. This is based upon using the 10 gallons of water per inch of Koi fish rule. Don't forget though please, to calculate the pond size based on fully grown Koi.
Here is a good pond calculator for you to use.
It would be remiss not to mention at some point, like now, that it is entirely feasible to have a Koi pond that is shallower than four feet. However, this is only the case if you purchase Koi at around 3 to 4 inches in size, and are prepared to give them up when they outgrow the space.
Nonetheless, this is a hot topic for debate as many of the 'given up Koi' end up spending their lives in aquatic stores never finding a new home. A moral and ethical dilemma which we will leave you to decide upon.
garden pond
A stunning koi pond over 4 feet deep
Why Does A Koi Pond Need To Be So Deep?
As already mentioned, briefly, not providing your Koi with a pond that is deep enough will lead to problems in their care and welfare. This is for a number of reasons as follows:
1. Koi are very active
Koi are an active fish that need a lot of space to swim around in. This includes being able to move up and down the water column in order to build up muscle and maintain their streamlined shape. Koi kept in shallow ponds tend to become obese and end up with a rugby ball shaping.
2. Avoid rapid water temperature changes
As cold-water fish whose body temperature matches that of the water they live in, Koi thrive in temperatures between 18 to 25 °C (64 to 77 °F). They are also, perhaps surprisingly, for fish that live in outdoor environments relatively sensitive to temperature fluctuation.
Rapid or sudden change can lead to physical stress. This can result in disease and possibly even death which is certainly something you do not want. By providing depth, and hence more water volume, you can avoid rapid temperature changes. This is because larger water volumes will cool or heat up with far less speed than smaller ones.
3. Deep ponds insulate them from the cold
Sticking with the same theme of temperature, a shallow pond can be incredibly detrimental to your Koi's health and welfare in winter. This is because although they are a cold-blooded species that can withstand lower temperatures, down to 10 °C (50 °F), they will not fare well below this.
In this regard, a deep pond helps, as Koi spend most of their time during winter at the bottom where the deepwater insulates them from the air temperature.
Plus, whilst Koi can tolerate the lower temperatures of winter, they cannot survive being frozen. So, as 6 inches or more depth in your pond can freeze during this time it is not hard to see that in winter the mantra ' the deeper the better' fits even more!
frozen koi pond
Never allow a koi pond to freeze over completely
Are There Any Other Benefits To Having A Deep Koi Pond?
One of the simplest, but most valuable, in many cases, benefits of having a deep pond is that you can achieve the large water capacity Koi require in a relatively small space. Most gardens, after all, will be spacious enough to host a pond with an 8 feet by 6 footprint and a 4 feet depth.
Good water quality is also easier to maintain in a deeper, hence larger water volume, pond. This is due to unwanted chemicals such as ammonia, nitrite, and nitrate building slower and is easier to control in larger water volumes.
This is especially helpful for those ponds that contain Koi or Goldfish as they are 'dirty fish' that produce a lot of waste.
Finally, but certainly not least in importance, regarding pond depth is the prevention of predators feasting on your beloved Koi. Deep water gives them somewhere to escape and retreat to where birds such as Heron won't be able to reach.
This is particularly relevant in winter when your Koi will be hibernating, sluggish, and easier to catch.
heron eating a fish
Deeper ponds protect your koi from predators like Herons
What Are The Best Options For Building And Creating A Deep Koi Pond?
When it comes to building the ideal Koi pond, there are four main possibilities that will achieve your end goal. These range from the 'easy to install' to the 'it's going to take some work' and also relatively cheap to expensive.
1. A Prefabricated Mould
Made from plastic or fiberglass, prefabricated molds are potentially the most expensive option when it comes to building a pond. However, they are also comparatively one of the easiest to install too. They simply require a hole digging that matches the shape of your mold and 'hey presto' you have a pond.
Prefabricated ponds are also great if you want a pond that has different depths and shelves for plants. Some plants need to be close to the water's surface.
However, many prefabricated moulds are not suitable for Koi ponds as they do not have the required depth and you may need to shop around to find one. The biggest prefabricated one we could find was only 500 Gallons. Far too small for adult koi.
2. A Pond Liner
One of the most cost-efficient options when it comes to building a pond is the pond liner. A pond liner can be made from butyl or vinyl. They are perfect for the Koi pond enthusiast as they can be moulded to any depth hole you choose.
They will, however, need a little more effort than the moulded option would. However, the reward of any shaped pond, as deep as you want, is certainly worth the extra effort.
How Deep Should A Pond Be For Koi Fish? 1
How Deep Should A Pond Be For Koi Fish? 2
3. A Concrete Pond
Absolutely the most expensive of all the options, the concrete pond will definitely require some hard graft to build. However, on the flip side of the coin, they are, for many, the only option too.
They are strong, leakproof, and incredibly long-lasting with added benefits for your Koi that are hard to resist. Carbonate produced in the concrete and grout buffers pH swings in your pond's water.
Concrete ponds also have the added bonus of being able to be any shape, size, and depth you fancy. If you can dig the hole and concrete it, you can have it as a Koi pond. You will need to take care, however, that you do not create any sharp edges or leave the concrete too rough. Sharp and rough areas can injure your Koi.
4. A Children's Pool
There is some debate over whether the use of children's pools as ponds is feasible. Some say that they are a fantastic, inexpensive, and easy to install way of having a Koi pond in your garden. Others state that they are not cost-saving as they are not strong enough and will need replacing after a short while.
Whilst it would be fair to say that both sides of this debate make good points, it would also be apt to add, that the children's pool has a couple of, possibly, major advantages.
Firstly, you can pack up and move this pond fairly easily should you need to. Secondly, it does not require any digging up of your garden. A children's pool will sit, without being intrusive, in any level part of your garden.
Do I Need Any Special Equipment For A Koi Pond?
Technically, no as all ponds being outside