Support Local Art
art Buy local culture Support local tourism
From: Backpackers South Africa
Why it's important to support local art
Supporting local talent is a great opportunity for cultures to connect, and for communities to grow together. There are so many reasons why you should support local work, and apart from it driving tourism and rewarding innovative minds for their beautiful talents, art has the ability to share common values and beliefs between different groups of people. This type of communication is important for society.
No matter the place or origin of the piece, what matters is skills used to showcase that beautiful social structure.
 It fuels the economy
In such tight economic conditions, artists struggle to sell their work and individuals struggle to support them because of the cost. With local art, it's affordable and it's easier to support because you're supporting content that resonates with you.
The art is original and different
The beauty of local art is that there are so many African art styles to choose from. Be it landscapes, portraits or wildlife, local artists always offer something original and unique. Most pieces are designed without the latest technologies to assist or speed up the process, therefore these handmade pieces are one-of-a-kind. When you buy something that is carefully crafted and different, it brings a sense of exclusivity into your purchase.
It's affordable for society
When you support and buy from local artists, most of them aren't well-known for their work, which is why it tends to be affordable in the beginning. That piece of art then becomes a long-term investment, because as the artist becomes more recognisable, the piece of art will rise in value.
 It creates a sense of culture
Art is a common denominator in almost every country's history. Creativity is a beautiful experience that brings people and communities together, regardless of race, gender, age or religion. Take African art for example, artists always express their feelings towards a specific topic which resonates with many people. That feeling then brings cultures together to celebrate our heritage.
It drives tourism
As mentioned, art is a universal language that people appreciate and respect. Over the years, people have lost hope in African creativity, but slowly it's becoming a refreshed tourist attraction for many travelling to S.A
It inspires young minds
Younger generations are delving into creative careers where they've started using their talents to earn money. In order to keep the trend going, our existing communities need to support local art to show children just how important and special it is.
Final words
Beyond the creative benefits that art has on society, art has a measurable impact on our economy, health and well-being, society and education. It allows people the opportunity to communicate across barriers of language and culture, where words cannot be used to express the same thoughts.
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list of known hosts.
 Mon Dec 4 11:08:13 PST 2006
 [grid@node1 grid]$ ssh node2 date
 Mon Dec 4 11:08:35 PST 2006
 At the end of this process, the public host name for each member node should be registered in the known_hosts file for all other cluster nodes.
 If you are using a remote client to connect to the local node, and you see a message similar to "Warning: No xauth data; using fake authentication data for X11 forwarding," then this means that your authorized keys file is configured correctly, but your SSH configuration has X11 forwarding enabled. To correct this issue, proceed to "Setting Display and X11 Forwarding Configuration".
 3. Repeat step 2 on each cluster node member.
If you have configured SSH correctly, then you can now use the ssh or scp commands without being prompted for a password. For example:
[grid@node1 ~]$ ssh node2 date
Mon Feb 26 23:34:42 UTC 2009
[grid@node1 ~]$ ssh node1 date
Mon Feb 26 23:34:48 UTC 2009
If any node prompts for a password, then verify that the ~/.ssh/authorized_keys file on that node contains the correct public keys, and that you have created an Oracle software owner with identical group membership and IDs.
E.2 Configuring Kernel Parameters
This section contains the following:
The kernel parameter and shell limit values shown in the following section are recommended values only. For production database systems, Oracle recommends that you tune these values to optimize the performance of the system. Refer to your operating system documentation for more information about tuning kernel parameters.
E.2.1 Minimum Parameter Settings for Installation
During installation, or when you run the Cluster Verification Utility (cluvfy) with the flag -fixup, a fixup script is generated. This script updates required kernel packages if necessary to minimum values.
If you cannot use the fixup scripts, then review the following table to set values manually:
Parameter Value File
semmsl semmns semopm semmni 250 32000 100 128 /proc/sys/kernel/sem
shmmax Minimum allocation:
536870912 (512 MB)
Maximum allocation:
 - Linux x86: At least 1 byte less than 4 GB, or _PHONE_.
 Recommended: More than half the physical memory.
 - Linux x86-64: At least 1 byte less than the physical memory
 Recommended: More than half the physical memory
See My Oracle Support Note 567506.1 for additional information about configuring shmmax.
shmmni 4096 /proc/sys/kernel/shmmni
shmall _PHONE_ /proc/sys/kernel/shmall
file-max _PHONE_ /proc/sys/fs/file-max
ip_local_port_range Minimum: 9000
Maximum: 65500
rmem_default 262144 /proc/sys/net/core/rmem_default
rmem_max _PHONE_ /proc/sys/net/core/rmem_max
wmem_default 262144 /proc/sys/net/core/wmem_default
wmem_max _PHONE_ /proc/sys/net/core/wmem_max
aio-max-nr _PHONE_ /proc/sys/fs/aio-max-nr
If the current value for any parameter is greater than the value listed in this table, then the Fixup scripts do not change the value of that parameter.
E.2.2 Additional Parameter and Kernel Settings for SUSE Linux
On SUSE systems only, complete the following steps as needed:
 1. Enter the following command to cause the system to read the /etc/sysctl.conf file when it restarts:
 # /sbin/chkconfig boot.sysctl on
 2. On SUSE 10 systems only, use a text editor to change the /etc/sysconfig/boot.sysctl parameter RUN_PARALLEL flag from yes to no.
 3. Enter the GID of the oinstall group as the value for the parameter /proc/sys/vm/hugetlb_shm_group. Doing this grants members of oinstall a group permission to create shared memory segments.
 For example, where the oinstall group GID is 501:
 # echo 501 > /proc/sys/vm/hugetlb_shm_group
 After running this command, use vi to add the following text to /etc/sysctl.conf, and enable the boot.sysctl script to run on system restart:
 Only one group can be defined as the vm.hugetlb_shm_group.
 4. Repeat steps 1 through 3 on all other nodes in the cluster.
E.3 Checking OCFS2 Version Manually
To check your OCFS version manually, enter the following commands:
modinfo ocfs2
rpm -qa |grep ocfs2
Ensure that ocfs2console and ocfs2-tools are at least version 1.2.7, and that the other OCFS2 components correspond to the pattern ocfs2-kernel_version-1.2.7 or greater. If you want to install Oracle RAC on a shared home, then the OCFS version must be 1.4.1 or greater.
For information about OCFS2, refer to the following Web site:


text:
The Discovery Center Tot Lot with roof was designed to give infants and toddlers a fun playground fit for their size. This early learning childhood play structure is perfect for your daycare, head start or early head start programs. The Louise tot lot includes many learning activities giving the teachers a fun way outdoors to interact with the children.
- Two deck structure
- Play features are Clock Panel, Shapes and Objects Panel, Window Panel, Gear Panel, Bongo Drums, Rain Wheel, 1-2-3 Step and a slide
- Textured sides to promote sensory development
- Clock Panel: Children practice telling time by manipulating the hands on the Clock Panes
- Shapes & Colors Panel: Teaches key concepts such as shape recognition, colors and numbers
- Bongo Drums & Rain Wheel: Children are provided open-ended opportunities to creatively express themselves
- 1-2-3 Step: Wide design
- commercially compliant to CPSC and ASTM standards and IPEMA certified.
- Available with or without a roof
- Anchoring using a mounting kit is required for structure to be compliant with commercial playground structures. We suggest inground mounting package
Available Model Number:
DC-Seed-Discovery Center Tot Lot without roof
DC-Seedr-Discovery Center Tot Lot with roof

source: openbmb/Ultra-FineWeb


Japan's Speedy Egg Technology
Japan uses high tech technology to check and package eggs. The system used has a process of cleaning, checking for cracks and blood spots, and then packaging the eggs. As stated in the video, the whole process takes about ten minutes to complete. The cleaning process involves several steps to make sure the egg is completely safe, and proceeding that process red and blue lights check for any other spots that were missed. The next step is checking for cracks. Eggs are checked for cracks by the eggs being tapped 16 times by mini hammers. The final stage is the packaging process. This process involves the eggs being put into package and being labeled. The whole process takes up to ten minutes, and 33 packages of eggs can be produced in 1 second (Speedy and Safe – Japan's Egg Technology). That is a lot of packages for one second! Technology has allowed faster and more efficient packaging for factories.
Every country has some type of system they use to produce products, farm land, and much more. Not all use technology, but technology is being implemented at a fast rate in countries. Implementing technology will only benefit companies because of how fast products can be produced, and the quantity that can be produce in a single day. Japan has taken advantage of technology, and the egg factory uses the fastest technology available to package all the eggs. Japan is being smart and using technology to mass produce at a fast rate. Other countries and factories need to observe this and realize technology comes with a tremendous amount of benefits.
Speedy and Safe – Japan's Egg Technology. Ministry of Foreign Affairs of Japan, 2013. Youtube Video.
The AgBot
A system that can completely control data and record, plus monitor farms and agriculture areas. This system for helping farmers is called AgBot. What are AgBots? An AgBot gathers and stores information to its computer system that can then be accessed online by using a smartphone or computer. AgBots are solar powered, compact, and robust, which means that it can be deployed for up to weeks at a time (agbot.org). This robot is a new system to help farmers on their land, and to keep information organized an accessible.
AgBots can perform a lot of duties to benefit farmers. These dues are monitoring irrigation and water levels, remotely turning pumps or appliances on and off, sending sms alerts during specific events, monitoring and recording rainfall, humidity, soil, air temperature, soil content, and electricity use, and recording upload or sms photos in real time (agbot.org). AgBots can perform numerous tasks, but this is only a small list of the tasks an AgBot can do. AgBots can operate independently for long periods of time because they are solar powered with rechargeable batteries. This device is all of the electronic luxuries we have in the world combined into one robot that can do all of the work on its own. As of right now, there are five AgBots available through order from Australia.
The five AgBots are WaterBot, SuperBot, SpyBot, ActionBot, and FieldBot. Each bot completes different tasks for its specific duties that are wanted. WaterBot, ActionBot, and SpyBot can be purchased for $199. While the FieldBot is $299, and the SuperBot is $599. These robots are a new technology movement to improve farmer's efficiency on the farm. It also improves that amount of accurate data farmers collect on a regular basis. Technology improves to help peoples lives become easier, and helps the ones the need the most help. Farmers need the most help because of the long days and nights they spend working. These systems can help a farmer in any way needed, but the biggest benefit is all of the stored information available to access on a computer or smartphone. Technology is the new helping hand for famers, and the implementation of it could lead to great success on the farm.
"AgBot." - Agricultural Robotics. N.p., n.d. Web. 15 Nov. 2014.


text:
Crystal Soil Ball for horticulture
Crystal soil balls that contain tiny holes (cannot be seen by bare eyes) that hold air and water droplets. Plant roots are able to absorb water from the crystal balls. Grow plants without the hassles of keeping dirt. Soil is dewatered for compact shipment and storage, simply add water to activate the little beads to turn them into crystal soil Odor free and insect free － ideal for indoor home/office desktop plants etc. Crystal soil can be a substitute for dirty soil.
The pictures shown are for reference only


100% Vegan Fashion Verified by AMSlab and PETA
Vegan fashionVegan fashion is revolutionizing the way you are shopping and dressing. As more and more people join this new trend, (which more than a trend is a way of life), the industry is transforming to satisfy the demand of these consumers.
The products that make up the vegan fashion are all those that do not contain leather, skin, wool, exotic skins or any other tissue derived from animals.
AMSlab in collaboration with the organization PETA, has developed a control methodology to verify the absence of products of animal origin in clothing, footwear and accessories under the vegan standard. It is the "Vegan Product" seal, which allows consumers to quickly identify this type of item.
Betting on the concept of animal welfare, AMSlab offers the AMSvegan test kit, which allows fashion brands to identify on the label that a product is vegan, increasing its value and recognition by ensuring that it uses materials that are respectful with animals. At the same time, they will be protecting the end user, helping him to find vegan products effectively so they can make purchases that fit their values.
Today, AMSlab has positioned itself as one of the market leaders in the quality control sector with a high degree of specialization in matrices or high complexity components, for which they develop innovative methods that increase the specificity and quantification capacity of any compound, such as, for example, the 3 technologies with which they ensure the absence of any animal product:
1. Fiber test: verifying the absence of animal fiber through a specifically developed chemical analysis.
2. Test of materials: Through spectroscopy identify the absence of polymeric materials and synthetic leather, components of animal origin.
3. Chemical test: examining the absence of glues and adhesives of animal origin through chemical analysis tests.
Links of interest:
Related Posts


The Victims of Jack the Ripper
It is not known for certain how many victims Jack the Ripper actually had, although there is a general consensus that there were 5 victims.
The problem with regards the exact number is that the generic police file that cover the Jack the Ripper murders, the Whitechapel Murders file, actually has eleven names on it.
Some of these may have been victims of the ripper other most certainly were not.
Emma Elizabeth Smith, who was attacked in early April 1888, and who was the first lady whose name appeared on the Whitechapel Murders file, was almost certainly the victim of a local gang and therefore not a victim of the killer whom we now know as Jack the Ripper.
In early August 1888 Martha Turner was found murdered on a first floor landing of George Yard Buildings. There is still a considerable amount of debate as to whether or not she was a ripper victim.
Those who say that she wasn't argue that her injuries were different to those suffered by the five acknowledged victims. Indeed, the nature of her injuries were more of a frenzied knife attack as opposed to the more calculated mutilations inflicted on the bodies of the five later victims.
Those who believe that Martha may well have been Jack the Ripper's first actual victim argue that her killer most certainly targeted her throat and abdomen, just as the ripper did with his later victims, and that a this may have been a learning curve for the murderer in that, whoever was responsible, would have been left covered in blood. This may have led him to have developed the modus operandi that became his hallmark by which he asphyxiated his victims before commencing the mutilations, a method that would have resulted in minimal blood spattering.
The five definite ripper murders began on 31st August 1888 with the murder of Mary Nichols in Buck's Row, Whitechapel.
This crime was followed a week later by the murder of Annie Chapman on 8th September in Hanbury Street.
On the 30th September 1888, and after an absence of several week, the killer struck twice in less than an hour, killing Elizabeth Stride in Berner Street and Catherine Eddowes in Mitre Square.
The, on 9th November 1888, the body of Mary Kelly was found in her room at 13 Miller's Court off Dorset Street.
There were later murders that may have been the ripper's work, but many of the police at the time, and many experts today, believed and believe that Mary Kelly was the last of Jack the Ripper's victims.


text:
Experience counts: Integrating spearfishers' skills and knowledge in the evaluation of biological and ecological impacts
Fishing experience and skills are not commonly considered in recreational fishery studies. To analyse potential different biological/ecological impacts of three experience levels of spearfishers (novice, intermediate and experienced), access point surveys were conducted over a period of 10 months in São Miguel Island (Azores archipelago). Groups differed in terms of catch rate and composition, species size and vulnerability (i.e. intrinsic vulnerability index of fishes to fishing). Experienced spearfishers explored different areas along the island coast, fished deeper and farther off shore, were more selective regarding fish size and target species, reached higher catch weights and had catches with a higher mean index of vulnerability. Results suggest that catch composition and rate not only depend on fish community and ecosystem health, but also on the expertise of the fishers who operate in a given area. Consequently, scientific studies should consider fishers' experience in the survey design and data analysis to not overor underestimate their potential impact.
(Links to preprints and postprints are checked for validity at the time of publication. If this link does not work, please let us know in the comments below. Additionally, you may use the Google Scholar link below to search for alternative freely-available versions of this resource.)
Report an error or inaccuracy
Notice an error in the Literature item above? Please let us know in the comments section below. Thank you for helping us keep the Literature Library up-to-date!


Streaming Videos
Students can access lessons through IRIS education telecourse streaming video services. This organization provides another option for viewing your Telecourse lessons. IRIS is a private organization which is NOT a part of City College of San Francisco.
To view the lessons, students must use a computer connected to the internet and pay a one time $35 fee. To make a purchase, you must have a valid Visa or MasterCard account. The following is the IRIS website:
The following are Requirements for Viewing Digital Delivery Products
 1. Upon purchase, links to your "purchased" videos are emailed to you and are also available from the "My Videos" link, these are visible only when you are logged in
 2. A Pentium class, or equivalent, computer with speakers.
 3. A broadband internet connection, such as DSL or cable
 4. Video streaming will not work with dial-up modems or America Online
 5. Windows Media Player 9.0 or higher
 6. An Internet browser installed on your computer - Internet Explorer 6 (or higher) or Firefox 2.0 (or higher)


text:
Evaluation of tourism web sites: A theoretical framework
The paper outlines a theoretical framework for the discussion and identification of indicators measuring the properties of web sites. In this framework we distinguish between the web site as a medium for describing an object, the web site as an object of description and the normative judgement of a web site. The framework is the basis for a project currently carried out and which has as its aim to establish indicators for tourism web sites and use them in an open benchmarking process to enforce the improvement of the set of independent web sites marketing a given tourist destination both individually and as a resource in the collective presentation of the destination. The case studied is the Sognefjord region in Western Norway.
In: Proceedings from ENTER 2004, Cairo, Egypt (Springer Verlag)


text:
Proposals:Realistic meteor showers
BLURB - TO BE EXPANDED
At the moment, Stellarium can show meteors, but they are simply decorative - they appear at random points at a rate set by the user. The existing code of the MeteorMgr class can be used as a base for a plug-in that shows more or less scientifically accurate meteor showers. They are not random - the meteors appear to "stream" from a single point in the celestial sphere, the radiant.
(See the Wikipedia article on meteor showers for more information. A lot of time-lapse photographies of meteor showers that show the effect can be found on the Web.)
This feature can take several forms: - Weak form: Allows the user to define a meteor shower and/or pick it from a list, and then to turn it on and off on a whim.
- Strong form: Keeps a meteor shower catalogue as with the other kinds of objects tracked by Stellarium, and shows only what should be in the sky for the given date. The catalogue should contain information about the radiant and the annual changes in the zenith hourly rate (as meteor showers typically have a peak and are active some time before and after that; a normal distribution function can do).
- Very strong form: Use a professional model for predicting meteor showers, based on the orbits of the clouds of space particles that cause them.

source: HuggingFaceFW/fineweb-edu


text:
|Writen By Angie (Parizo) Baumhover on 6/27/98
This page is copyrighted and not to be used without written permission from Angie Baumhover
|DAPPLE - Spots where some of the color is lighter, can occur in all colors. The color is usually lighter than the base color.
If the dappling occurs in the eyes, the eyes are blue (may not be solid blue.) Dapple is not a carried gene,
one parent must be dapple for any of the puppies to be dapple.
|DOUBLE DAPPLE - Only occurs when both parents are dapples but does not mean the entire litter is dapple or double dapple;
there can be solid colors produced. Must have areas of white on the body for it to be a double dapple. Both parents must
be dapple to produce a double dapple.
|DAPPLE PIEBALD - AKC does NOT recognize this pattern. This comes from breeding a dapple carrying for piebald to
a piebald and/or from breeding a solid carrying piebald to a dapple carrying piebald. The dog will appear to look like
a double dapple even though it is not. Dapple Piebald's should be registered as a Dapple. Dapple Piebald's should
only be bred back to a solid that dose not carry for piebald.
|PIEBALD - Piebald only occur when both parents are piebald or carry it. Areas of full color on a white background,
example; fox terrier. They may also have ticking (small spots of color in the white field, example; English Setter.)
which may just be a few little spots on the toes and muzzle, or the ticking may be heavy. You can have different
patterns on a piebald in the spots. Piebalds do not have any blue in their eyes. Both parents must be piebald or
carry the piebald gene.
|BRINDLE PIEBALD - Brindle and Piebald are both a separate pattern however AKC does accept both patterns on
one dog; they are registered as a brindle piebald. This pattern is commonly seen on red piebald. The base color
(red) will have stripes of black in the color with the piebald pattern also showing.
|BRINDLE - Stripes all over, looks a lot like a tiger, commonly seen with red.
|SABLE - (can only appear in long hair) These terms (especially sable) are often mistakenly used to refer to an interspersion
of black hairs on back and neck over red color. A true sable/wildboar will appear to be black/tan from a distance. The
undercoat beneath being red, Sable/Wildboar is a very heavy layer of black over the base coat color. This is an
uncommon pattern. This is a pattern that can not be truly labeled until pup reaches 6 months of age.
Many pups labeled sable/wildboar lose the black overlay and become simply red with no pattern.
|Phone: _PHONE_ | Email: _EMAIL_
Copyright © to Starlight Kennel. All rights reserved.
All Graphics and Content Copyrighted
WI Number 402120-DS


Children in foster care waiting for adoption by age group in the United States
Change Indicator
(i) Select Table Type:
 - Detailed
 - Sort / Rank
Data Provided By
Definitions: Children and youth waiting for adoption from birth up to age 20 by age group. Most states allow children to remain in the foster care system until their 18th birthday, though some states have age limits that extend a few years beyond this. The current indicator includes children up to age 20 regardless of their state limit. National estimates include Puerto Rico.
Percent estimates in each age group are based on the total ages 0 to 20 where age is known. Missing age data are excluded from percentage and frequency distributions. Age was determined by calculating the number of days between the child's date of birth and the fiscal year end date. In the AFCARS adoption file, only the month and year of the child's birth are provided, so the date of children's birth was imputed as being on the 15th day of the month. National estimates include Puerto Rico.
Footnotes: Updated June 2021.
N.A. - Data not available.
N.R. - Data are not reported.


Primeval Horse Gelatinate 2kg
€113,90 €92,39
Article number: 9938
Delivery time: 1-2 days
Horses are very active animals. Some performance horses do intense training for years, while others run freely on open plains. What they all have in common though, is a tendency to develop joint problems. Due to their posture, their joints are an extremely vital part of its mobility that is permanently tested throughout its life. That is why Primeval Gelatinate has been manufactured using the patented collagen hydrolysate Fortigel that keeps the joints supple. The collagen hydrolysate alongside the minerals and the collagen type II provide essential building blocks to protect and maintain the joints throughout their years. Primeval Gelatinate allows your horse to enjoy a mobile life right up to their final years.
 - ✔ Strengthen joints
 - ✔ Repair and regenerate cartilage
 - ✔ Fight bacteria that breakdown cartilage
Collagen hydrolyzate, minerals, aroma, collagen type II.
Analytical Components
crude protein 64%, crude fiber 0%, crude fat 0%, crude ash 10%, sodium 0%
Daily Dose Primeval Gelatinate
- Preventive for (sports) horses, older horses, breeding mares, pregnant mares (at least the last three months of gestation), foals growing, enters, twenters and stallions:
mix one measuring spoon of 22.5 grams twice a day with the food (chunks, carrots or slobber).
- For horses and ponies up to 450 kg:
one measuring spoon of 22.5 grams once a day.
To support injuries to tendons, ligaments or joints, doubling the indicated dosage is recommended, or consult your veterinarian.
Mix with water or oil.
0 stars based on 0 reviews


text: Cab filtration systems can be used to protect vehicle operators from hazardous air contaminants. In a cab filtration system, a fan draws air through filters and pressurizes the cab with this filtered air. This article describes the application of a low-cost, optical particle counter to evaluate the performance of tractor cab filtration systems. The tractors were equipped with environmental enclosures to protect the operators from pesticide exposures that occur during air blast spraying in orchards. Prior to testing, all environmental tractor cabs underwent a complete maintenance overhaul followed by a careful inspection by the manufacturer's field representative. As part of this maintenance effort, 13 tractors with cab filtration systems were tested in an enclosure. A Met One model 227B two-channel optical particle counter was used to measure the aerosol concentration outside and inside the cab. Ambient aerosol and/or aerosol generated by burning incense sticks were used to challenge the stationary cab filtration system in an enclosure. The ratio of the outside to inside concentration (Co/Ci) is the exposure reduction attained by the cab system. Alternatively, the inside concentration divided by the outside concentration times 100 (Ci/Co x 100) gives the percent penetration. All 13 tractors were tested for leak sites. Leak sites were identified and sealed. This process was repeated until each cab showed an exposure reduction ratio Co/Ci of at least 50 (aerosol penetration into the cab Ci/Co x 100 was less than 2%) at the 0.3-0.5 microm particle size interval.


I was recently reading through some posts on this site. A question struck me -
Why does an object attached to the end of a string which is further attached to an accelerating car behave differently than it would if the object is attached with a rod welded to the roof?
P.S.- Apparently there is a misunderstanding with my question. What I mean by 'differently' is that the object when attached through a string tries to remain in rest, but then accelerates with the car (inertia), causing the string to make an angle $\theta$ with the vertical, whereas it is not the case when the object is attached through a rod, i.e., the rod always make $0^\circ$ with the vertical.
enter image description here
Edit - I have added a picture, if that helps...
 - $\begingroup$ Can you clarify what do you mean by 'behave differently'? $\endgroup$ – Cluse Mar 7 at 17:34
 - $\begingroup$ _USER_ Is it clear now? $\endgroup$ – user290607 Mar 7 at 17:49
 - $\begingroup$ Not to me. I think you're relying on people knowing the class of problem you're talking about, but I don't, so I'll drop it. In general, especially in this type of question with multiple scenarios of things attached together involving angles, etc, a picture really helps. $\endgroup$ – tom10 Mar 7 at 19:07
 - 1
 $\begingroup$ Why do you say the rod will always remain vertical? $\endgroup$ – Sandejo Mar 7 at 19:13
 - $\begingroup$ Is the rod able to rotate? Or is it a rod connected to the bus in an unmovable fashion? $\endgroup$ – Deschele Schilder Mar 8 at 9:04
Alright then. Imagine you find yourself on a bus. There is a string hanging from the ceiling. Next to the string, a rod is welded to the ceiling. I think you agree that the string is movable in all directions while the rod is not (unless you attach the rod to a flexible joint).
Now attach a mass to the end of the string and one to the end of the rod. Can you see it? The bus starts to accelerate. The passengers feel themselves pushed to the seat they are in. Just so, both masses feel a force directed to the rear of the bus. The mass on the string is free to move (within the confine the string imposes) and the string will make an angle with the vertical direction. This angle depends on the value of the mass attached. The higher the mass, the smaller the angle (the force of gravity, which pulls the mass down gets bigger). The mass on the rod will not be able to move because the rod is welded to the ceiling. Only if the rod can move in the way the string can move, both the string and the rod will make an angle with the vertical upon acceleration.
Do you get me?
 - 1
 $\begingroup$ No. That still does not answer my question. Why does not the rod bend? $\endgroup$ – user290607 Mar 8 at 13:04
 - 2
 $\begingroup$ Ah. now its clear. The röd bends a little. If it would bend visibly it wouldnt be a rod. $\endgroup$ – Deschele Schilder Mar 8 at 16:10
 - 1
 $\begingroup$ I have accepted your solution. Since the rod bends a little, the horizontal component of the force on the bus is the only force on the object, which is the same as compared to the string. Where is the difference (there is a subtle difference, I think). Please elaborate. $\endgroup$ – user290607 Mar 8 at 17:11
 - $\begingroup$ _USER_ What do you mean by the force on the bus? $\endgroup$ – Deschele Schilder Mar 8 at 17:14
 - $\begingroup$ The force which causes the bus to accelerate. $\endgroup$ – user290607 Mar 8 at 17:15
I understand I have not understood the question right when I answered the following:
Because of inertia. If no forces are acting on an object, the objects velocity does not change. Using a string the car accelerates the object to a certain velocity and when slowing down the object will continue to move towards the car as no forces are acting on it (until it hits the car where the normal force of the mass of the car slows it down at once). Using a rod the object again accelerates with the car as it is tied to it. But when the car slows down, the normal force of the mass of the car immediately acts on the object thrue the rod, slowing down the object at the same time as the car slows down.
Second Try:
If I understood correctly what is meant here, the reason for the object making an angle to the "vertical" is simply inertia and the fact that it the string has a finite length: The object (attached outside of the car on the ceiling or inside on the ground) wants to stay at rest but is accelerated. The only way to stay as much at rest as possible is to move down (in addition to moving to the opposite side of the acceleration relative to the car) and thus making that angle.
If you meant horizontal instead of "vertical" (the object being attached to the back of the car outside) then the reason is chaos of aerodynamics. Aerodynamics predicts that the object moves in every direction, despite being dragged back by inertia and thus making that angle. But I'm not that familiar with aerodynamics and am therefor not able to give you more details. What I do understand is that when using a fixed rod welded to the car, the object has no degree of freedom whatsoever. Its position is completely determined by the car. A string gives the object all three degrees of freedom $(r,\theta,\varphi)$, inspite of some boundaries: $r\le L$ (length of string), $\varphi\in [0,\pi]$ (object can't go into the car), $\theta\in [0,\pi]$ (boundaries for $\theta$ are normal). Having these degrees of freedom the chaotic consequences of aerodynamics act on the object.
 - $\begingroup$ I think that the object hangs on a string or rod instead of lying on the ground (of the bus or behind it). $\endgroup$ – Deschele Schilder Mar 8 at 9:13
 - $\begingroup$ _USER_ I have extended my answer. $\endgroup$ – Roger Mar 8 at 11:37
 - $\begingroup$ Do you envision the object in or outside the car? I'm not sure if I understand the connection between the deviation from the vertical and chaos of aerodynamics. If I hang (inside a bus) a mass on a string, then on acceleration of the bus the object the string will deviate from hanging vertical (which a rod melted to the ceiling can't do). $\endgroup$ – Deschele Schilder Mar 8 at 11:45
 - $\begingroup$ _USER_ I have mistaken vertical with horizontal. The answer is updated now. $\endgroup$ – Roger Mar 8 at 11:51
 - $\begingroup$ _USER_ I don't think my question has anything to do with aerodynamics. You can think of the bus in vacuum if you wish. $\endgroup$ – user290607 Mar 8 at 12:34


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ALUMINA- X-Ray Analysis; MATHEMATICAL TRANSFORMATIONS - Fourier Transforms; SILICA - X-Ray Analysis; X-RAYS - Scattering; SMALL-ANGLE X-RAY SCATTERING; VORONOI CELL MODELS
Small-angle X-ray scattering (SAXS) can be used to obtain interphase surface areas of a system, such as a supported-metal catalyst, composed of internally homogeneous phases with sharp interphase boundaries. Measurements of SAXS for samples of porous silica, alumina, platinum on silica, and platinum on alumina are reported. A variety of models and forms for the correlation function, the Fourier transform of which gives the X-ray scattering, are considered, and theoretical and measured intensities are compared. A criterion of fit for comparing models with different numbers of parameters is proposed. It is shown that values for the single interphase surface area can be obtained independently of a model. However, fitting intensities using a model-based correlation function gives information about the structure of the system. The two-cell-size Voronoi and the correlated Voronoi cell models are useful in this regard.
Brumberger, H., Delaglio, F., Goodisman, J., & Whitfield, M. (1986). SMALL-ANGLE X-RAY SCATTERING ANALYSIS OF CATALYSTS: COMPARISON AND EVALUATION OF MODELS. Journal of Applied Crystallography, 19(pt 5), 287-299.
Creative Commons License
This work is licensed under a Creative Commons Attribution 3.0 License.


text:
Surface Oxide State on Metal Powder and its Changes during Additive Manufacturing: an Overview
Artikel i vetenskaplig tidskrift, 2018
Quality and usefulness of the powder for additive manufacturing (AM) are strongly determined by the surface composition of the powder. In addition, taking into account harsh conditions during AM process, significant changes in the powder surface chemical composition are taking place, limiting powder recyclability. Hence, knowledge concerning amount of oxides, their composition and spatial distribution on the powder surface determines further powder recycling. This communication summarizes possibilities of qualitative and quantitative analysis of powder surface chemistry by surface-sensitive chemical analyses using XPS and HR SEM coupled with EDX.The effect of alloy composition, AM process applied and powder handling on the surface composition of the powder are addressed. Results indicate significant enrichment in the thermodynamically stable surface oxides in case of high-alloyed powder for both, EBM and LS processes. A generic model for the oxide distribution, depending on the alloy composition and powder surface degradation during AM manufacturing, is proposed.


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|Nicotine Gum (Code C15663)|
|Terms & Properties|
Preferred Name: Nicotine Gum
Definition: A chewing gum containing nicotine used as a substitute for the active ingredient in tobacco. Nicotine chewing gum reduces the withdrawal symptoms associated with smoking cessation.
NCI-GLOSS Definition: A chewing gum that contains a small dose of nicotine, which enters the blood by being absorbed through the lining of the mouth. This helps stop nicotine cravings and relieves symptoms that occur when a person is trying to quit smoking. A prescription is not needed for nicotine gum.
Label: Nicotine Gum
NCI Metathesaurus Link: C0068722 (see NCI Metathesaurus info)
Synonyms & Abbreviations: (see Synonym Details)
External Source Codes:
|CAS Registry Number||96055-45-7 (see NLM ChemIDplus info)|
|Name||Value (qualifiers indented underneath)|
Additional Concept Data:
|Defined Fully by Roles: No|


text:
LV standard motors
This guide provides basic information about IEC low voltage motors. In this context, low voltage refers to motors that operate at voltages less than 1 000 V and produce a maximum power of 1000 kW.
IEC low voltage motor ranges
In this overview, motors are classified primarily according to their fundamental physical differences, and secondarily, according to their purpose of use.
The last category of motors include, for example, marine motors, brake motors, and smoke extraction motors, which are based on the basic induction motor but have modifications that vary according to the purpose of use. Their features are not further described here.
Energy efficiency standards
The International Electrotechnical Commission (IEC) has introduced standards relating to energy efficient motors.
IEC 60034-2-1 specifies rules concerning efficiency testing methods and IEC 60034-30 defines efficiency classes for a wide range of electric motors connected direct on line.
IEC 60034-30-1 (which becomes valid in 2014) takes a step further in widening the scope of motors subject to efficiency classes and introduces the IE4 class. VSD-driven motors are out of the scope of this standard and will be dealt with in a standard of its own.
|Title:||Low Voltage Motors – Motor Guide – ABB|
|Download:||Right here | Video Courses | Membership | Download Updates|


How to Read a Manometer
Difference of Height in a Manometer
-•• Wikimedia Commons
A manometer is a device that measures pressure with a column of liquid. A simple manometer consists of a U-shaped tube that contains a liquid. If the pressure is different between the two ends of the tube, the liquid will move away from the source of greater pressure. The instructions that follow assume one side of the tube is open to the air, and a source of positive pressure is connected to the other side.
 Measure the distance between the liquid's current level on one side and its established zero point, which may be indicated by a mark on the tube. Multiply this distance by 2, because the surface of the liquid on the right goes down by the same distance that the left side goes up; the total distance of the liquid movement is therefore twice the measured movement of one side.
 Determine the pressure in water inches. Assuming the liquid in the manometer is water, this is simply the result from step 1 in inches. Although non-standard, this is a common measure of pressure since it can be determined by a direct measurement.
 First, convert the non-metric measurements to metric ones. Then, convert the manometer reading to standard units of pressure. Use the standard formula p = d * h * 9.8 where "p" is the pressure in pascals, "d" is the density of the liquid in the tube in kilograms per cubic meter, "h" is the doubled height difference in meters from step 1 and 9.8 is the downward force of gravity, 9.8 meters per second squared. So if you measure a height difference of.01 meters, double it to.02, multiply by 1,000 kg per cubic meter for water, and multiply by 9.8 to get 196 pascals of pressure.
 - Note that the above calculation gives a gauge pressure that is relative to normal atmospheric pressure. When one side of the tube is open and the liquid is at the same level on both sides, the pressure on the connected side is standard atmospheric pressure — 14.7 psi or 101.325 kilopacals at sea level. To determine absolute pressure, you must add standard pressure to your results. For the above example, the positive pressure of 196 pascals is 196 + 101,325 = 101,521 pascals of absolute pressure. If your elevation is substantially higher or lower than sea level, get a barometer reading and use its indicated pressure instead of 101.325 kilopascals.
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How to Calculate the Air Flow & the Static Pressure...


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Posted: September 7th, 2021
Skill Builder: Annotated OutlineAn outline is the scaffold upon which you build your paper. You probably already use a mental outline when you plan a paper, perhaps without even being aware of it. Writing the outline can give you a visualization of your plan. An outline provides both focus and direction for the paper, shows where relevant points and arguments need to be made and also identifies areas where more supportive evidence is needed.What is an annotated outline?Because you are writing a research paper, your paper is built around the research findings that you located in your search.When you prepare an annotated outline, you will note the research that supports each section of the paper. This will help you see any areas that need further research to support them.The following example may help support the transition of your paper from a collection of research notes to a fully developed paper.Suppose the research topic you chose was the relation of childhood bullying to self-esteem. The title of your paper is: Self-esteem in childhood bullying.When researching the paper, you found conflicting research results. Some research showed that children with low self-esteem tended to bully others, while other research showed that children with extremely high self-esteem were bullies. Looking closer, you began to see that this research could be divided into studies investigating different variables, such as gender, age, and ethnic background. Now, you want to turn this into a research report.An annotated outline might look like this (all citations are fictional):Topic: The relation of childhood bullying to self-esteem: Too much or too little?Overview of childhood bullyingDefinitions of bullying (Simpson, 2010; O'Connor, 2008)Types of bullying (Yang, 2009; Sinisi, 2011)Self-esteem in childhoodDefinitions of self-esteem (Whitefield, 2009)Impact of self-esteem on behavior in childhood (Liebermann, 2010)Research on the relation of self-esteem to bullying in childhoodGender, self-esteem, and childhood bullyingSelf-esteem and same-gender bullyingSelf-esteem in boys bullying boys (Pryzborski, 2012)Self-esteem in girls bullying girlsSelf-esteem in opposite-gender or non-gender specific bullying in childhood (no research found)Age, self-esteem in childhood bullyingSelf-esteem and bullying from 6-9 (Brennan, 2011)Self-esteem and bullying from 9-12 (Mendez, 2010; Lee, 2011)Family structure, self-esteem, and childhoodSelf-esteem and bullying in children in single-parent families (Shams, 2012)Self-esteem and bulling in children in dual-parent families (Mugaddam, 2011)Ethnicity, self-esteem and childhood bullyingInter-ethnic bullying and self-esteem (Jacinto, 2009; Akbarzadeh, 2010)Intra-ethnic bullying and self-esteem (Lawrence, 2011)ConclusionsSummary and suggestions for future studiesReferencesPreparing an annotated outline in this way will give you a way to organize and clarify your plans. Additionally, it gives your instructor a chance to provide feedback on the proposed structure of the paper before you begin to write. You can also see which subtopics you need to research further before proceeding with the final draft.AssignmentThis week, you will develop an annotated outline that will help support the transition of your paper from a collection of research notes to a full-blown paper. Preparing an annotated outline in this way will give you a way to organize and clarify your plans and allow your instructor a chance to give you feedback on the proposed structure of the paper before you begin to write it. You can also see which subtopics you need to research further before proceeding with the final draft.One way of talking about outlines is to describe an outline as a pre-writing outline, or as a reverse outline. The prewriting outline is prepared before the paper is written, so you can see the plan you want to follow. Some people, however, must write their ideas out before they take shape; if that is your preferred approach, you can use a reverse outline method. Write out a draft, then go back and try to outline it. If you cannot find the structure in your paper, then you probably need to do some serious revisions. Think of a pre-writing outline as scaffolding, and a reverse outline as an X-ray of your paper.When you prepare an annotated outline, you will note the research that supports each section of the paper. This will help you see any areas that need further research to support them.Here are some great resources, located under your weekly resources, for Reverse Outlining:Purdue Online Writing Lab: Reverse OutliningUNC, The Writing Center: Reverse OutlineSupport your work with at least 10 peer-reviewed research articles published in the past five years.Length: 2-3 pages, plus reference list in proper APA formatYour outline should demonstrate thoughtful consideration of the ideas and concepts that are presented in the course and provide new thoughts and insights relating directly to this topic. Your response should reflect scholarly writing and current APA standards. Be sure to adhere to Northcentral University's Academic Integrity Policy.Upload your document and click the Submit to Dropbox button. Your instructor will review the outline and provide feedback including the go-ahead to proceed with your Signature Assignment.Due DateSep 5, 2021 11:59 PM
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Why my solar battery charges / discharges rapidly?
It may be that charging and discharging the batteries too quickly is a sign of inadequate battery sizing, improper IMEON settings, or the end of battery life.
As a first step, ask your installer to make sure that the battery has been properly dimensioned and that the IMEON parameters have been set taking into account the technical specifications of the batteries. It is important to note that incorrect sizing of a battery can lead to premature wear.


I'm trying to figure out if some emerging markets change over time.
 - First of all I am going to check for changes in volatility. What would be a good method to do this. And do you suggest comparing the first half of the time series with the second or comparing the first 1/3 with the last 1/3.
 - Secondly, for the correlation. I would like to check if the correlation between one emerging market and the SPX or FTSE100 changes over time, because the correlation should increase as the market 'emerges' and integrates with the emerged markets. Here as well, I wonder whether I should use halves or thirds.
I'm trying to figure out what would be a good method to test this. Do you have any suggestions?
 - $\begingroup$ Why don't you use a rolling window for each? $\endgroup$ – SachaTheBrave Oct 5 '20 at 11:40
As mentioned in a response to a different question, there are a number of academic papers that use non-parametric tests for determining changes in variance/volatility in financial time series. Whether or not these are "good methods" depends on how you define "good" as they have some obvious drawbacks.
This depends on your objectives, but for a cursory examination look at the changes of volatility and correlation over time as suggested by _USER_. The rolling (or sliding) window is quite helpful in locating the intervals of particular interest.
Here's an example which shows 1-day returns for three ETFs (SPY, EEM, and EWZ) and a 1-month sliding standard deviation of the returns:
SELECT symbol, time, daily_return, stddev(daily_return) as volatility
 SELECT symbol, time, close, close/LAG(close)-1 AS daily_return
 FROM atsd_session_summary
 WHERE symbol = 'SPY.US'
 AND datetime BETWEEN '2020-01-01' AND current_day
enter image description here
This type of sliding window (preceding-to-current) is not centered, with the volatility visually lagging the deviations observed in the 1-day return series. Centered windows are possible but used less often.
Your Answer


Wanted: Effectively-Once Processing in Azure
This experimental post is a question. The question is too broad for StackOverflow, so I'm posting it here. Please engage in the comments section, or forward the link to subject experts.
TL;DR: Are there any known patterns / tools / frameworks to provide scalable, stateful, effectively-once, end-to-end processing of messages, to be hosted in Azure, preferably on PaaS-level of service?
Motivational Example
Let's say we are making a TODO app. There is a constant flow of requests to create a TODO in the system. Each request contains just two fields: a title and a project ID which TODO should belong to. Here is the definition:
type TodoRequest = {
 ProjectId: int
 Title: string
Now, we want to process the request and assign each TODO an identifier, which should be an auto-incremented integer. Numeration is unique per project, so each TODO must have its own combination of ProjectId and Id:
type Todo = {
 ProjectId: int
 Id: int
 Title: string
Now, instead of relying on some database sequences, I want to describe this transformation as a function. The function has the type (TodoRequest, int) -> (Todo, int), i.e. it transforms a tuple of a request and current per-project state (last generated ID) to a tuple of a TODO and post-processing state:
let create (request: TodoRequest, state: int) =
 let nextId = state + 1
 let todo = {
 ProjectId = request.ProjectId
 Id = nextId
 Title = request.Title
 todo, nextId
This is an extremely simple function, and I can use it to great success to process local, non-durable data.
But if I need to make a reliable distributed application out of it, I need to take care of lots of things:
 1. No request should be lost. I need to persist all the requests into a durable storage in case of processor crash.
 2. Similarly, I need to persist TODO's too. Presumably, some downstream logic will use the persisted data later on in TODO's lifecycle.
 3. The state (the counter) must be durable too. In case of crash of processing function, I want to be able to restart processing after recovery.
 4. Processing of the requests should be sequential per project ID. Otherwise I might get a clash of ID's in case two requests belonging to the same project are processed concurrently.
 5. I still want requests to different projects to be processed in parallel, to make sure the system scales up with the growth of project count.
 6. There must be no holes or duplicates in TODO numbering per project, even in face of system failures. In worst case, I agree to tolerate a duplicated entry in the output log, but it must be exactly the same entry (i.e. two entries with same project id, id and title).
 7. The system should tolerate a permanent failure of any single hardware dependency and automatically fail-over within reasonable time.
It's not feasible to meet all of those requirements without relying on some battle-tested distributed services or frameworks.
Which options do I know of?
Traditionally, this kind of requirements were solved by using transactions in something like SQL Server. If I store requests, TODO's and current ID per project in the same relational database, I can make each processing step a single atomic transaction.
This addresses all the concerns, as long as we can stay inside the single database. That's probably a viable option for the TODO app, but less of so if I convert my toy example to some real applications like IoT data processing.
Can we do the same for distributed systems at scale?
Azure Event Hubs
Since I touched IoT space, the logical choice would be to store our entries in Azure Event Hubs. That works for many criteria, but I don't see any available approach to make such processing consistent in the face of failures.
When processing is done, we need to store 3 pieces: generated TODO event, current processing offset and current ID. Event goes to another event hub, processing offset is stored in Blob Storage and ID can be saved to something like Table Storage.
But there's no way to store those 3 pieces atomically. Whichever order we choose, we are bound to get anomalies in some specific failure modes.
Azure Functions
Azure Functions don't solve those problems. But I want to mention this Function-as-a-Service offering because they provide an ideal programming model for my use case.
I need to take just one step from my domain function to Azure Function: to define bindings for e.g. Event Hubs and Table Storage.
However, reliability guarantees will stay poor. I won't get neither sequential processing per Event Hub partition key, nor atomic state commit.
Azure Service Fabric
Service Fabric sounds like a good candidate service for reliable processing. Unfortunately, I don't have much experience with it to judge.
Please leave a comment if you do.
JVM World
There are products in JVM world which claim to solve my problem perfectly.
Apache Kafka was the inspiration for Event Hubs log-based messaging. The recent Kafka release provides effectively-once processing semantics as long as data stay inside Kafka. Kafka does that with atomic publishing to multiple topics, and state storage based on compacted topics.
Apache Flink has similar guarantees for its stream processing APIs.
Great, but how do I get such awesomeness in.NET code, and without installing expensive ZooKeeper-managed clusters?
Call for Feedback
Do you know a solution, product or service?
Have you developed effectively-once processing on.NET / Azure stack?
Are you in touch with somebody who works on such framework?
Please leave a comment, or ping me on Twitter.
Cloud developer and researcher.
Software engineer at Pulumi. Microsoft Azure MVP.
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Molecular Scale Heat Engines and Scalable Quantum Computation
Leonard Schulman
We describe a quantum mechanical heat engine. Like its classical counterpart introduced by Carnot, this engine carries out a reversible process in which an input of energy to the system results in a separation of cold and hot regions. The method begins with a reinterpretation in thermodynamic terms of a simple step introduced by von Neumann to extract fair coin flips from sequences of biased coin flips. Some of the experimental set-ups proposed for implementation of quantum computers, begin with the quantum bits of the computer initially in a mixed state. Each qubit is $\epsilon$ polarized --- in the state $\ket{0}$ with probability $\frac{1+\epsilon}\{2}$, and in the state $\ket{1}$ with probability $\frac{1-\epsilon}\{2}$, independently (or nearly so) of all other bits. The heat engine may be used to transform this initial collection of $n$ qubits into a state in which a near-optimal $m=n[{1+\ep \over 2} \lg (1+\ep) +{1-\ep \over 2} \lg (1-\ep) -o(1)]$ qubits are in the joint state $\ket{0^m}$. These qubits can then be used as the registers for a quantum computation. The heat engine is described at the level of an algorithm implementable in any quantum system capable of massive coherent states. A particular implementation is also described for a system of nuclear spins arranged in a chain. The temperature the cold qubits reach is inverse polynomial in $n$.
created Tue Mar 14 17:48:16 PST 2000


text:
Operational procedures at U.S. Geological Survey gaging stations include periodic leveling checks to ensure that gages are accurately set to the established gage datum. Differential leveling techniques are used to determine elevations for reference marks, reference points, all gages, and the water surface. The techniques presented in this manual provide guidance on instruments and methods that ensure gaging-station levels are run to both a high precision and accuracy. Levels are run at gaging stations whenever differences in gage readings are unresolved, stations may have been damaged, or according to a pre-determined frequency. Engineer's levels, both optical levels and electronic digital levels, are commonly used for gaging-station levels. Collimation tests should be run at least once a week for any week that levels are run, and the absolute value of the collimation error cannot exceed 0.003 foot/100 feet (ft).
An acceptable set of gaging-station levels consists of a minimum of two foresights, each from a different instrument height, taken on at least two independent reference marks, all reference points, all gages, and the water surface. The initial instrument height is determined from another independent reference mark, known as the origin, or base reference mark. The absolute value of the closure error of a leveling circuit must be less than or equal to ft, where n is the total number of instrument setups, and may not exceed |0.015| ft regardless of the number of instrument setups. Closure error for a leveling circuit is distributed by instrument setup and adjusted elevations are determined. Side shots in a level circuit are assessed by examining the differences between the adjusted first and second elevations for each objective point in the circuit. The absolute value of these differences must be less than or equal to 0.005 ft. Final elevations for objective points are determined by averaging the valid adjusted first and second elevations. If final elevations indicate that the reference gage is off by |0.015| ft or more, it must be reset.


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Perfect Chemistry Short Answer Test Questions
Simone Elkeles
Purchase our Perfect Chemistry Lesson Plans
Short Answer Questions
1. In which fictional town is "Perfect Chemistry" set?
2. What grade is Brittany starting as the novel begins?
3. What is Brittany's last name?
4. What is Brittany's mother's tone toward Brittany?
5. Who is Brittany's sister?
6. From what disease does Brittany's sister suffer?
7. What device does Brittany's sister use to help her get mobile?
8. Shelley gets a spot on her ________________.
9. What does Brittany use to cover up the spot in #8?
10. What does Alex do soon after awakening in Chapter 2?
11. Who is Carmen?
12. "Perfect Chemistry" is written from which point of view?
(read all 180 Short Answer Questions and Answers)
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Video:Teaching Kids to Put on Coatswith Kathy Moore
Is your toddler ready to put on his or her own coat alone? This simple method makes putting a coat on feel like a game, and it's also easy to replicate.See Transcript
Transcript:Teaching Kids to Put on CoatsHi I'm Kathy Moore for About.com Parenting. Whether it's dressing to ward off winters chill, or wearing a light jacket in spring or fall, even toddlers can learn how to put on their own jacket. This program will demonstrate a simple method to teach your child to put on his own coat.
When Are Kids Ready to Put on Coats?As soon as kids can walk and stand steadily on their own, they can be taught to put on their own outer coat using this simple method.
Easy Steps to Put on CoatsPlace the coat on the floor. Lay it flat with the inside facing up. Instruct your child to stand facing the top or collar of the coat. Then have them bend over and place their arms in the sleeves like this. Once the child has his arms in the sleeves have him lift the whole coat up and over his head. Then when he brings his arms down he will have completed the task of putting on his own coat.
Watch the simple steps again:
- Place the coat on the floor
- Lay it flat with the inside facing up
- Stand facing the top or collar of the coat
- Bend over and place the arms in the sleeves
- Then lift the whole coat up and overhead
- When the arms come down you are all set
Thanks for watching. To learn more visit us on the Web at parenting.about.com.
About videos are made available on an "as is" basis, subject to the User Agreement.


Take the 2-minute tour ×
I have a generic N-ary expression tree and I want to convert the same to a binary tree. Is there any well defined algorithms to do the same?
I tried going thro' different algorithms of converting N-ary tree to expression tree like _URL_ but thats not going to work, as they don't worry about precedence and all.
share|improve this question
Can you expand on your requirements for the binary tree, vs the nary tree? Anything specific... or is your only requirement that children of a node, are simply still descendants of the same node? – ChrisCM Jun 4 '13 at 13:52
add comment
1 Answer
Simple answer.
Step 1: Convert N-ary expression tree with different levels of precedence into an N-ary tree where each node has only a single level of precedence.
Step 2: Convert that tree into a binary tree.
If you're seeking a straightforward solution rather than an efficient one, it may be easy to explode each node into levels matching your precedence, then after you have a binary tree collapse out the obviously useless nodes. If you want a more efficient solution, then you'll want to be more cautious in the initial expansion.
share|improve this answer
add comment
Your Answer


text:
To safely use a flat iron on fine hair, use a steam-producing iron, such as Teflon-coated hot tool brands, and apply a heat protectant to hair before straightening. Use a lower heat setting and run the flat iron through the hair consistently, not stopping at any one section longer than another, and quickly. Only use a heated tool once or twice a week.Continue Reading
Do not style hair with a flat iron while it is still wet to avoid steam damage. Wet hair produces a boiling effect that boils the center of a hair shaft. This causes a break in the walls of the medulla and produces bubbles in the shaft that decreases shine. Hair becomes rough, dry and is more easily snapped off when it is styled while wet.
Using a flat iron daily causes frizzy hair of differing lengths because of hair breakage. Change the flat iron periodically when there is buildup on the plates or the surface of the plate becomes sticky. This buildup and stickiness is caused by burned hair cells and it causes more damage to hair if used for too long. The signs of heat damage include dull, dry hair that breaks easily, as well as damage to the scalp or hair follicle and reduced shine. If these are happening to one's hair, seek a professionals help to rehabilitate the strands.Learn more about Hairstyling Tools


Take the 2-minute tour ×
Suppose we have a set $M = (0,1) \subset R$ of reals well-ordered as the first uncountable ordinal.
Let $M(a) = \lbrace x \in M : x < a \rbrace$. For every $a \in M$ set $M(a)$ is countable. That's why every increasing sequence is bounded:
$$(*) ~~~~~~~~~~ \forall \lbrace a_1,...,a_n,...\rbrace \subset M ~~\exists b \in M : a_i < b ~~\forall i \in \mathbb{N}.$$
Now suppose that we can pick elements from $M$ at random. And let's try to build an increasing random sequence by the following algorithm. Let we have an increasing sequence of elements $\{a_1,...,a_n\}$. Pick some random number $b$. If $b > a_n$ set $a_{n+1} = b$. Otherwise pick other random number instead of $b$ and check $b > a_n$ condition. Continue this till success. Since we pick numbers at random it shouldn't be a problem to construct an infinite sequence. But every infinite sequence is bounded! Which means that in our infinite process we will never be able to pick random number which is greater than some number $c \in M$. This is even more astonishing since $M(c)$ is countable and $M \setminus M(c)$ is uncountable!
Any thoughts how to "solve" this paradox?
share|improve this question
To pick elements from $M$ at random you need to have a probability measure on $M$ to sample from. What is it? – François G. Dorais Jun 6 '13 at 13:36
_USER_ I guess he uses Lebesgue measure on $M$. – The User Jun 6 '13 at 13:41
_USER_: So $M$ is Lebesgue measurable and not null? – François G. Dorais Jun 6 '13 at 13:42
_USER_ Hm? The standard probability measure (Lebesgue measure) on the unit interval is not null. – The User Jun 6 '13 at 13:47
_USER_: So Dan is assuming CH? – François G. Dorais Jun 6 '13 at 13:52
4 Answers 4
up vote 10 down vote accepted
I think the paradox can be solved by the observation that $c$ is defined a posteriori, so it is not true that you avoid $c$ during all the process, since $c$ is in fact an outcome of the process.
You could do a similar paradox without bothering with well-orderings: pick a sequence $X=\{a_1,a_2,\dots\}$ in $(0,1)$ by choosing each $a_i$ at random, one after the other.
Then your "paradox" is that each $a_i$ you chose belong to $X$, which has measure $0$ and is countable, whereas $(0,1)$ is uncountable with measure $1$. But since $X$ is the outcome of the process and was not defined at the time of the choosing, it is not a real paradox.
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I agree with DK that the "paradox" has nothing to do with the assumed well-ordering. I think it also has nothing to do with the decision to choose a countable sequence of elements $a_n$. Suppose we just pick a single $a$, at random, with respect to Lebesgue measure. Since the one-element set $\{a\}$ has measure zero, we can say, paraphrasing the question, "in our process, we never pick a number outside $\{a\}$. This is even more astonishing since $\{a\}$ has just a single element and its complement is uncountable."
I trust that this situation, involving just a single $a$, is more familiar to most people and therefore doesn't look paradoxical. I claim that the situation in the question is quite analogous and should not be considered paradoxical either.
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Well, $a,a,a,\ldots$ could be randomly chosen. The problem with random things is that you never know! :-) Also dilbert.com/strips/comic/2001-10-25 and _URL_ – Asaf Karagila Jun 6 '13 at 16:41
The answers already given amount to, "With probability 1, a probability-zero event will happen when you do something randomly." This is absolutely correct, but let me give a slightly different take on the OP's argument that is more specifically about well-orderings.
Let's simplify matters, and just do the following: select $\alpha,\beta\in\omega_1$ randomly. What is the probability that $\alpha<\beta$ (in the usual ordering on $\omega_1$)? Naive arguments show that the probability is 1. But by those same arguments, the probability that $\beta<\alpha$ is 1.
In the reals context, the paradox is: if I select a real $r=\langle s_0, s_1\rangle$, what is the probability that $r\in X$, where $$ X=\lbrace u=\langle v_0, v_1\rangle: f^{-1}(v_0) < f^{-1}(v_1)\rbrace,$$ and in turn $$ f: \omega_1\rightarrow\mathbb{R} $$ is a bijection? (Note that this argument is really about well-orderings, and not just about the inevitability of probability-zero events.)
This is just Freiling's argument against $CH$ (see _URL_ This argument was discussed on MO here: Axiom of Symmetry, aka Freiling's argument against CH. Briefly, the reason it isn't generally found convincing as an argument against $CH$ is that it tacitly assumes that the reals are well-orderable if and only if they are well-orderable in a measurable way. So if you believe that there are non-measurable sets, this argument really shouldn't be very convincing.
(On the other hand, if you find this argument intuitively appealing, maybe $L(\mathbb{R})$ is right for you!)
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For simplicity let us drop the condition that $a_\{n+1\}>a_n$. It just means that we exclude a countable set in every step, that should not be very interesting. We can still consider the supremum of a sequence with respect to the well-order and ask wether it is a given countable ordinal $c$. This event has probability zero, since it is contained in the set of all sequences where the first value is contained in a certain countable set. This set is contained the countable union of sets of the form $\left\{a\right\}\times [0,1]^{\mathbb{N}}$, which have measure zero. QED. You simply constructed many different sets of probability zero containing sequences with infinitely many different values (but you enforce that the values are contained in a certain countable set, and there are many countable subsets of the reals). I do not think that this is very astonishing.
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The definition of a tune is a song, a melody, having correct musical pitch or being in the correct key.(noun)
Tune is defined as to adjust or adapt a condition, situation, instrument or voice.(verb)
See tune in Webster's New World College Dictionary
Origin: ME, var. of tone, tone
See tune in American Heritage Dictionary 4
Origin: Middle English
Origin:, variant of tone, tone; see tone.
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A Definition Of Absorption
Source: Adapted from the National Institutes of Health
What does the term "absorption" mean? The term "absorption" refers to to take in substances through the skin or mucous membranes. To find out more about this term, please search the news section of this website for related articles and information.


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Formula for success in naming your protagonist:
1) Pick a nondescript, normal first name, like "John" or "Thomas".
2) Pick a word for the last name that you have never heard used as anyone's last name, ever. This word must reek coolness, and it must also have some semantic connection with the character's purpose in the story. Pick a legendary warrior, like "Constantine", or a word with boatloads of implied meaning, like "Covenant".
1 + 2 = Badass


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Legal powers
See also the discussion of legal powers in our Working Paper on Text-driven Normativity.
Working definition
 1. A legal power refers to the ability of a legal subject to achieve an intended legal effect
 2. A legal power is attributed by positive law
 3. One can have a legal power to attribute legal powers
 4. All legal powers are both constituted and constrained by positive law
 5. The written or unwritten Constitution of a state attributes legal powers to legislate, administrate and adjudicate, thus calling them into existence (the constitution 'constitutes' these powers), and qualifying them (the constitution also 'regulates' these powers, e.g. by attributing them to countervailing powers)
 6. In the case of public law legal powers are constrained by the legality principle.
 7. In the case of private law legal powers are constrained by the reasonableness principle (or equity in common law jurisdictions).
 8. The attribution of legal power plays out in all domains of law:
 1. Private law, for instance, attributes to the owner of a legal good the legal power to transfer related property rights, provided specific conditions have been fulfilled
 2. Criminal law, for instance, attributes to the court the legal power to impose specified (maximum) punishments, provided the conditions of a specific criminal offence have been fulfilled
 3. Administrative law, for instance, attributes to legal subjects the legal power to object to decisions made by public administration, provided specific conditions apply
 4. International law, for instance, attributes to states the legal power to conclude treaties, subject to the constraints imposed by the sources of international law
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A Truly Natural Resource: What To Do With The Placenta
What do you really know about placentas? If you're like the majority of people, the "tree of life" is probably pretty mysterious. Despite being vital to both maternal and fetal health, the National Institute of Child Health and Development says that the placenta is the "least understood human organ." That's starting to change as more scientists study the invasive organ, a pattern Denise Grady wrote about for the New York Times, but outside the laboratories people are taking the placenta into their own hands. Literally. So we asked: what are some of the most popular and strange things people are doing with their placenta?
Art: The tree-like look of placenta has been noted for centuries, by cultures all over the world. If you'd like to capture that image in a piece of art, there are artisans who specialize in making casts or placenta jewelry. Prints in particular have taken off and producer Taylor Quimby offered us a step-by-step placenta print tutorial if you'd prefer to do it yourself.
Taylor's Tips For Placenta Prints
1. Get a box to put everything on standby, at least a few weeks before the due date. This isn't something you'll want to figure out day of.
2. Hit up your scrapbooking friends for supplies like rollers and sponges. Get some ink or paint. Helpful tip, darker colors work best. You can paint the background on some canvases beforehand to have some options.
3. Rinse the placenta off, pat it dry. Stop and appreciate that you're holding a human organ in your hands.
4. Roll ink on on the tree-like side and press the paper to the placenta. To get a clearer print, especially around the stem, you'll probably want to flip the whole thing over and let gravity help out.
5. Get artsy! If you don't like the first print, go for a second or third try. You should have that grab-bag of art supplies on hand - in case inspiration strikes you, you want to be prepared.
Plant It: If those other suggestions don't appeal to you, this idea might. People are planting their afterbirth in gardens, or underneath trees. The idea is that the placenta can then return any nutrients to the Earth, and enrich bonds to nature in a circle-of-life manner. This tradition is actually found in other cultures, like Maori and Navajo, where it has been practiced for centuries. The US people are using it to nourish trees which can serve as a more permanent symbol in family yards and gardens.
Teddy Bears: Looking at pictures of these stuffies, you can hardly tell they might have stranger than normal origins. Though maybe that's being optimistic. Basically, the placenta gets treated in a curing process and is then used for the skin of a one of a kind teddy bear. Designer Alex Green started making the bears in 2008 and describes them as feeling like something in between leather and suede, though flexible. Huggable. Not the first adjective to come to mind when thinking about placentas, but now, thanks to Green, not the last.
Eat It: Now follow this for a minute. Does "eating it," meaning "eating the placenta that has just followed your child out of the womb" have a high initial gross factor? Yes. Does that wear off after learning more about the practice? Not entirely. But it is very interesting, and just might be a topic that comes up at the next baby shower/ medical conference/ conversation with someone who is pregnant.
Although no clinical studies have proven that the placenta can pass any of the vital nutrients it collects onto the mother if eaten, the trend is on the rise in the US. Placentas can be eaten raw, frozen and put into smoothies, and even steamed then dried then crushed into a powder which is put into capsules – one of the most popular methods. People who eat the afterbirth usually prescribe to the idea that eating the organ can help with post-partum recovery and lactation, among other things. And though it hasn't been scientifically proven to help, it hasn't hurt either – most mothers who consumed the placenta after the birth of one child said they would do it again the next time around.
You can hear the full interview with Denise Grady, New York Times reporter who wrote the article "The Mysterious Tree of a Newborn's Life: The Push to Understand the Placenta," here.


text:
The 1903 Ball in the Winter Palace — the famous luxurious ball during the reign of the emperor Nicholas II of Russia in the Winter Palace, St.-Petersburg (February 11 and 13). All the visitors were in fancy dresses on a fashion of 17th century (times of Alexis of Russia, 2nd tsar from Romanov dynasty).
Mikhail Gorbachev was general secretary of the Soviet Union Communist Party from _PHONE_. He was also the first democratically elected President in 1990. He played a key role in dismantling the Communist grip on power in both the Soviet Union and Eastern Europe. His aspirations for democracy and reform opened up the way for the end of the Cold War and the bringing down of the Berlin Wall.
Russian man who was coughing up blood and complaining of chest pains was found to have this 5 centimeter spruce tree growing inside his lung। Since the tree was too large to have been accidentally inhaled, doctors believe the man must have inhaled a bud which grew inside the lung.


text:
الگوریتم برنامه ریزی پویا برای برش بهینه مستطیل های مساوی
|کد مقاله||سال انتشار||مقاله انگلیسی||ترجمه فارسی||تعداد کلمات|
|24900||2005||14 صفحه PDF||سفارش دهید||محاسبه نشده|
Publisher : Elsevier - Science Direct (الزویر - ساینس دایرکت)
Journal : Applied Mathematical Modelling, Volume 29, Issue 11, November 2005, Pages 1040–1053
This paper presents dynamic programming algorithms for generating optimal guillotine-cutting patterns of equal rectangles. The algorithms are applicable for solving the unconstrained problem where the blank demand is unconstrained, the constrained problem where the demand is exact, the unconstrained problem with blade length constraint, and the constrained problem with blade length constraint. The algorithms are able to generate the simplest optimal patterns to simplify the cutting process. When the sheet length is longer than the blade length of the guillotine shear used, the dynamic programming algorithm is applied to generate optimal layouts on segments of lengths no longer than the blade length, and the knapsack algorithm is employed to find the optimal layout of the segments on the sheet. The computational results indicate that the algorithms presented are more efficient than the branch-and-bound algorithms, which are the best algorithms so far that can guarantee the simplest patterns.
The rectangular cutting stock problem occurs when rectangular sheets in stock are to be cut into smaller rectangles or blanks, to meet a customer's demand,, and. Where the blank area must be no larger than the sheet area, some trim loss is expected. Some customers may need blanks of different sizes. Those involved in mass production may want a large number of blanks of the same size. In the former case, nested layouts are often used and blanks of different sizes may appear in the same layout. In the latter case, only blanks of the same size can appear in a layout. This paper refers to the cutting stock problem of equal rectangles as the CSPER, where guillotine shear is used to cut the sheet into blanks. This type of cutting stock problem is also identified as the guillotine-cutting problem and, or the guillotine pallet loading problem, and is denoted 2/B/O/C of guillotine type. The CSPER in this paper includes four types of problems: the unconstrained problem where the blank demand is unconstrained, the constrained problem where the blank demand must be met exactly, the unconstrained problem with blade length constraint, and the constrained problem with blade length constraint. Several algorithms have been published for the CSPER,,, and. Agrawal presented a branch-and-bound algorithm (BBA) for the unconstrained problem. In reference, the BBA was extended to solve the constrained problem, and the unconstrained problem with blade length constraint. If the memory of the computer used to perform the algorithm is not large enough, the BBA will not guarantee the optimality of the solution. This will be further discussed in presenting the computational results. A polynomial time algorithm was introduced in for the unconstrained problem. The time efficiency of the algorithm is high. The patterns generated are slightly difficult to cut since they are often not the simplest ones. Arslanov constructed a linear time algorithm for the unconstrained problem in. The algorithm has the highest time efficiency. Similarly it does not guarantee that the patterns generated are the simplest ones for cutting. The dynamic programming algorithm was applied to solve the unconstrained problem in. It does not consider the blade length constraint, and neither guarantees the simplicity of the cutting process. This paper presents dynamic programming algorithms to solve the four types of problems mentioned above. First the dynamic programming algorithm for the unconstrained problem is constructed, which can generate the simplest optimal pattern. Then the algorithm is extended to solve the constrained problem. Another two algorithms are introduced to deal with the blade length constraint, one for the unconstrained problem, and the other for the constrained problem. Computations are performed to compare the algorithms with the branch-and-bound algorithms, which are the best so far that can guarantee the simplest optimal patterns. The results indicate that the algorithms of this paper are more efficient.
نتیجه گیری انگلیسی
Four algorithms based on dynamic programming are presented, which are capable of dealing with four types of problems often encountered in practice: the unconstrained problem, the constrained problem, the unconstrained problem with blade length constraint, the constrained problem with blade length constraint. Algorithm A is the basis of the others. It may generate the simplest optimal patterns, with the cutting process being simplified. This is important to practical applications. Another advantage of the DPA is the easiness to design and understand. Even the engineers may realize the algorithms to solve the CSPER of their factories. Although linear time algorithm exists for the CSPER, it does not guarantee that the pattern generated is the simplest optimal pattern. If the simplest optimal patterns are wanted, the BBA is the best so far. The computational results indicate that for problems of larger scale (such as the test problems of this paper), the DPA is much more time efficient than the BBA.


text:
From Wikipedia, the free encyclopedia
Warren could mean:
Animal husbandry [change]
- Warren, a rabbitry or fixed establishment of cuniculture, the breeding and raising of domestic rabbits. (The domestic use of warren is imprecisely extended to rabbit or hare burrows in the wild.)
Forest law [change]
- Warren (free) ("Free warren"), a type of hunting franchise under the Anglo-Norman Forest law
- In metaphoric use, warren refers to a tight agglomeration of inferior accommodations, such as a slum.
- Warren abstract machine, a Prolog (software) engine
- Warren Commission, which investigated the assassination of John F. Kennedy
- Warren Cup, a Roman antiquity
- Warren's Gate, an archaeological site
- Warren's Skipper, a type of butterfly
- Warren Wagon Train Raid, historic incident in Texas
Other pages [change]
|This disambiguation page lists articles with similar titles.
If a link brought you here, you can go back and fix it so it goes straight to the right page.


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3. Gentoo/Alt Technotes Guide
3.a. General Structure
Handling Users
There are differences between users in a Gentoo/Linux system and the ones in other Gentoo/Alt systems. These differences are usually a side problem that does not invalidate most of the work. Still, it's better to pay attention.
The first thing to check is to never use the root group. The group with id 0, called root on Linux is instead wheel on BSD and Darwin, (and probably other classical unices); while wheel group on Linux has GID 10. When you need to set the default permissions on a file (or a series of files), you should then use the command chown root:0 file instead, so that it takes the right permissions.
Important: This is the only one case where you should refer to a group or an user with its numeric ID instead of the name.
For every other case you should always use the name of groups and users, avoiding specifying them by ID as they can have different IDs on different systems.
Also, it's important to note that every ebuild that makes references to specific users and groups, should add them with enewgroup and enewuser, if it does not depend on the ebuild that adds them. So for example, cronbase adds cron user and group, as they can not be present on the users' systems.
It's not rare to create users that cannot login on a system. To do so, on Linux, the shell of those users is set to /bin/false. Unfortunately, this does not work on BSD-derived systems like Gentoo/*BSD and Gentoo/Darwin, as they use a more sofisticated approach, and /bin/false does not exists. enewuser function provide a simple way to create a disabled user: just use -1 as the shell for the newly created user, this way the function will take care of selecting the right shell for the disabled user, making use of /sbin/nologin where that is present (*BSD, Darwin and Linux using app-admin/nologin) or falling back to /bin/false when nothing else can be used.
Note: As of now eneweruser function fails when using /bin/false or any other direct "disabled" shell as shell for the user, forcing the ebuild developers to use -1 as it should be.
If you need to find out the home directory for a given user, you can't rely on the format of /etc/passwd or on the output of egetent, as they are different on FreeBSD and OSX. To avoid this, the egethome function (provided by portability eclass, but available inheriting eutils), returns the right field making sure that is the home directory for the user:
Code Listing 1.1: egethome usage
inherit eutils
homedir=$(egethome charlie)
3.b. Applications
Bash and shells
Bash is the default shell of Gentoo Linux, and it's on top of this that ebuilds are written. Because of this, Gentoo/Alt projects provides bash in their base system, as /bin/bash.
Ebuilds and scripts can use bashisms without problems as bash is provided, but in case of scripts, it's important that the first line reads as #!/bin/bash instead of just #!/bin/sh, to make sure that they are being executed with bash. The same goes for calling scripts from inside ebuilds, sh somescript is deprecated in favor of bash somescript so that bash is called for sure.
While bash should take care of managing [.. ] tests, it's anyway suggested to use [[.. ]] to run tests also when quoting the arguments correctly. This way, the tests are guarranteed to be expanded by bash internally and do not get executed by /bin/[ instead.
GNU tools and non-GNU userlands
Gentoo/Alt projects, a part from Gentoo GNU/kFreeBSD, aims to have a complete system that uses native versions of all the system's tools, of libc, and so on. However, there are some part of Gentoo's base system that does not work with BSD-like tools (not because they are broken, just because they are strictly POSIX). To work around this problem, we install a series of GNU tools g-prefixed. In a Gentoo/Alt system profile, you can always find these tools: GNU sed (as gsed), GNU make (as gmake), GNU awk (as gawk), GNU patch (as gpatch) GNU diff (as gdiff) and usually GNU cmp (as cmp, for compatibility with a couple other scripts). If you need GNU-style find command, you can also install findutils package that provides gfind and gxargs.
To allow users who prefers the GNU-style tools be comfortable, there is an ebuild sys-apps/userland-gnu that depends on coreutils and other GNU packages, that are always g-prefixed, and then links them inside /usr/libexec/gnu without the g-prefix. After adding them to $PATH, it's possible to use GNU tools in command line.
It's always preferred to use just the POSIX options, to be able to run the same script identical on Gentoo/Linux and Gentoo/Alt. In case you cannot rewrite the code not to use the GNU extensions, just add a dependency over the right package that provides the tool, and then do a simple test:
 1. Check for the g-prefixed tool
 2. Check that it works as expected for a GNU tool (usually this means that it accepts version option and reports GNU, FSF or the name of the package there)
And then select the right one you need.
Important: Inside an ebuild there are a few aliases that are used to make sure that they doen't break apart, so calling make, sed, patch and awk will call the GNU version of the tools.
Warning: The GNU tools' aliases works only if the tools are called by themselves, they won't work inside scripts called by the ebuild, and they won't work if called by find.. -exec or by xargs. In those cases, it's usually better to check for the right tool to call. An important exception is the usage of the sed command to call GNU sed: being widely used and difficult to check or fix, Portage 2.1_pre9 and later provides a wrapper script that calls GNU sed in any case, when used from ebuilds, if the $ESED variable is not set, in which case the called sed will be the one there indicated. This allows the usage of BSD sed when building BSD packages for instance.
To help with porting, there are a few constructs that are usually used out of habit that need to be fixed:
 1. cp -a: this is a GNUism, as the -a option is not present on POSIX cp. Its replacement is told to be -dpPR, but -d is not posix itself, so -pPR is what you should replace -a.
 2. cp --parents: this other GNUism is used to copy a series of files from a tree maintaining their prefix. There's no equivalent option in BSD userland, so this should be avoided. If you need this, instead use the treecopy function in portability eclass, that works exactly as a cp --parents -pPR call.
 3. seq doesn't exist on BSD userland, but there's a quick replacement: jot. Unfortunately its syntax is too variable, and poses a problem to manage. To avoid this, portability eclass has a seq function replacement that calls jot with the right parameters when called on a BSD userland. Still, make sure you're not trying to use some extra options to seq
Note: The -d option does not make a difference in almost all the cases, as it counts only when you have symlinks directly on the command line argument.
Using pmake
There are a few packages that require the use of pmake (parallel make, by NetBSD, the package we use is from Debian) to build on GNU userland, as the makefiles are incompatible with GNU make. As the name of this flavor of make varies depending on the userland you're in (it's pmake on GNU userland, bsdmake in Darwin userland and simply make in BSD userland. To avoid this trouble, you can use get_bmake function from portability eclass.
Code Listing 2.1: using get_bmake
src_compile() {
 $(get_bmake) || die "make failed"
If the package builds using ports-like interface, as done by FreeBSD system packages, bsdmk eclass (currently on Gentoo/Alt overlay) provides a simple way to handle the knobs: just add to ${mymakeopts} the list of knobs to pass during the pkg_setup() function, and then call mkmake and mkinstall to compile and install the packages as specified.
Note about different make
As the make command changes name depending on the system where it's being used, there is an important thing to keep in mind: recursive makefiles are often used to build subdirectories of a source tree, but sometimes they calls directly a new make command. This breaks when the makefiles are called with other versions.
To avoid this problem all the modern make commands sets an automatic variable $(MAKE) that carries the name of the command used to launch the make chain. Instead of calling a generic make, all the makefiles should then call $(MAKE) to be safe with different naming of the command.
Another fortunately less common problem is when a package decides that $(


Prepared4ALL Course 2: The Prepared4ALL Process in Action
It may not look like it but the people in this room are socially distanced. There is an American Sign Language (ASL) Interpreter in this room to sign for anyone who needs it.
Learning Objectives
- Describe the Prepared4ALL process and what each letter in the process stands for
Apply the Prepared4ALL process to create inclusive COVID-19 vaccine emergency dispensing sites (EDS)
Prepared4ALL: Course 2: The Prepared4ALL Process in Action Pre-Test
 - We want to know more about you. Please answer the questions below.
 - Please enter a number less than or equal to 1000.
 - Please rate how confident you are that you could do the following activities as of today.
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