This week marks the start of my 3rd trimester of pregnancy. 28 weeks. I can't believe it's come this fast. Despite being more than ready to meet this little girl and embrace the challenges of new motherhood, I am still woefully unprepared to bring her home and step away from my job for 3+ months. Still so much to buy and prep and do!
Preparing for baby in all the big and little ways that one prepares for such things has been both fun and stressful. Jonathan is hyper-involved in everything, but most of the research on baby gear and essentials has fallen to me—mostly because I've embraced it like it's a full time job. But one area where we've both been particularly attentive is to the issue of baby names.I don't know how most couples approach this kind of thing in the early stages of their relationship, but Jonathan and I—once we were each aware of the other's interest in having kids someday—talked openly about baby name preferences before nearly anything else, including marriage. It was probably because talking about baby names is one of my favorite topics of conversation period, full stop, and I forced him to talk to me about it. Six years ago, it was very important that he know how I felt about his preferred boy's name, Doc ("Hell no."), and it was necessary that I knew his feelings about my favorite girl's name at the time, Laila ("Not feeling it…").
He was such a good sport.
And so it went, the "What about…?" discussion happening a hundred times over the years, thus we were able to narrow down our top choices to a short list of possibilities that sat in stasis for upwards of three years. When we found out we were having a baby—and especially when we found out it was a girl—Jonathan's baby naming seriousness kicked into high gear. Something about the reality of picking a name for a real live person to have for their entire life makes you look at all your name choices differently. At least, it did for us.
A big discussion of late has been whether (and how) to honor family members in the naming of our baby. So many individual names and name combos we love, and that made our list, have little or nothing to do with family legacy. We liked the idea of family names, but neither of us thought it really mattered all that much when we were just ruminating over ideas. Now though… with an actual baby brewing… we are weighing all the pros and cons.
There are lots of pros and cons, it turns out.
So at 28 weeks, we're honing in on a much shorter short list of names, with one that's peaking out as the favorite. It's mind-boggling to have thought so much about baby names for so many years (long before Jonathan was even a blip on my romantic radar), and now… we get to name one. A girl who will hopefully live a long life with that name, carrying it into adulthood, hearing it through the voices of friends and lovers, putting it on job resumes!
The weight of such a life long decision is not lost on us. We're so honored to get the opportunity to name a human being—bestowing upon her the first little piece of her identity.
SO TELL ME: If you've got some favorite baby names, or your children are already named and you love talking about the why and how you came up with that name, let me know in the comments. Are there names you used to love, but your partner nixed them? What about names you are sad you couldn't use because you are done having children? I would absolutely love to read all about it!
Baby names. I seriously can't get enough.
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I can't get enough either! I'm so into names. I've often found myself reading the ragged, old "name your baby" book that was on our bookshelf time and again, because, damn, I'm so interested in names! I'm pretty 'in' with the idea of naming a baby at least in part, after family. Probably because I am named after great grand parents and I've also liked it and felt very connected to my heritage. I also think name spelling and diction is important. While I never had a concrete list, I just recently wrote some combinations down. Hopefully someday the stars will align enough that I will get to use them!
I would like to note that my suggestion of Vestibule DeMoney Hyatt was denied outright.


text:
The CSSC Hub
CSSC Advice to Business
HomeAbout – North East & Yorkshire
About – North East & Yorkshire
The Cross-Sector Safety and Security Communications (CSSC) North East & Yorkshire Hub launched April 2018.
This embarked a partnership between the public and private sectors in the seven counties of the North Eastern Region of England with a combined population of over 8.5 million. (Northumberland, Cleveland, County Durham, Humberside, North, South and West Yorkshire).
The North East & Yorkshire region has support from key public and private sector partners across the region including Police, Councils, Environment Agency, Home Office and National Counter Terrorism Police. Now operational with over 35 industry sectors, each of which is headed by one or more Industry Sector Leads (ISLs), many of whom have a National/International reach within their industries helping them address safety, security, resilience and emergency prepared issues.
CSSC in the North East & Yorkshire is a two-way communications vehicle. It facilitates the information flow of important messages from our key public services to local businesses within the region and enables such businesses to offer feedback to help shape the advice and guidance produced by public bodies in the future.
The key to this information conduit is the CSSC hub based at Kings Secure Technologies in West Yorkshire who operate as a dedicated point of contact between public and private sectors. CSSC North East & Yorkshire Hub is run by a Senior Management Board that oversees communications and an operational team that handles day-to-day activity and development.
We have the confidence that our region's contacts will grow and evolve as a communications network to suit the changing threat landscape. It is important to us that we provide businesses with the support they need from local public-sector bodies to combat threats and improve their resilience and emergency response plans.
About the CSSC
Find out more about the history and background to the CSSC
Recent news and messages
CSSC East Midlands – Winter Newsletter
View this web page as PDF thecssc-december2019c
16th January 2020 Read more
To receive CSSC North East messages, please register your business
CSSC North East & Yorkshire sponsors:
The Cross-sector Safety & Security Communications partnership is a registered charity: Charity No. 1153764

redpajama_set_name: RedPajamaCommonCrawl


The password would be filled in above but see below.
No the QR code will not work even on my network since the password was blanked.
However when I went to check the video a week later for some samples to post and it had quit recording after a day. The camera was still tracking movement just not recording to the cloud. I had not put an SD in yet so there was nothing to check there. So I deleted the camera from the app, reset the cam and did a readd. But it would not connect. I wasted hours trying stuff. Finally I tried setting up a wide open Access Point (AP) and noticed the password was still filled in. I removed it and it connected. Repowered and it still reconnected so I wiped it all and readded to the secured guest network and it still works. While I was at it I stuck a 32 GB SD in it.
You can only view video from the phone app (no web viewing).
No easy way to change WiFi password.
Some suspicious network activity has been reported so only use on a guest or other isolated network.
The above also probably means you should think twice about putting the app on and phone or tablet that has sensitive info on it.
Free 7 days of cloud recording.
Ridiculously cheap at just $38 including shipping.
Seems to do an OK job of tracking (by doing pan and tilt) and marking moving object in the video. (See videos below.) Note people have reported being creeped out by this and have to admit it does feel a bit weird and makes the camera seem a bit alive. I was actually surprised how little video was saved vs the amount of time the cam appears to be panning to look at things.
I posted some sample videos on YouTube with the motion and sound detection at the default values and motion detection masked to around the dog door. Unfortunately I can not really show you the mask because when you go back in to modify the mask it only shows till the video kicks in and then defaults back to the whole screen.
Basically it is top to bottom from the wall socket to the edge of the window.
Main things to note here are how random the video is. It was triggered by noise way more than motion.
Lastly connecting the cam is slow and fails fair amount. Being an encrypted guest network might be a factor in that though as mentioned above I would definitely suggest isolating from your network like that.
Since the cam does not record 24/7, if this was my only cam in there I would be thinking of taking off the mask and cranking the sensitivity. Though that would probably make finding video of actual motion harder to find. As is I already have 2 cameras recording 24/7 in there to me it is mainly another motion detector and hopefully gets a close up of who is using the door should I need to know. If they made an outdoor version of this I'd definitely have a spot for it and would probably recommend at double the price. Would think about a couple for the barn if I could monitor on a local PC since most of my cams are to let me see what is going on (as in what has the dogs upset) with as little distraction / time wasted as possible. Having to open an app, connect to a cam and find a notification just does not do that. To notify you with a video if something is moving where there should be no motion it is not bad. Especially for the price.
Found these instructions online for using Tiny cam to bridge the cam to the local NVR. They did not work for me. Might be some sort of manual firewall config though. Note they seem to connect to the server not the cam directly so you might be burning as much down bandwidth as up using them. When you test your connection it says it is receiving something but dropping all frames even if you point it at an address that does not respond which is either misleading or something else is going on.
However, trying to debug first I checked the regular app and it could not connect either till I rebooted the cam. Even after rebooting the cam it kept dropping out. So that might be an issue too. Oddly there are plenty of recordings which would seem to indicate the stream is getting to the cloud.
On a whim I tried connecting with the Amazon Show. But it now seems to think my one cam is two cams with the same name and will not connect to I rename one.
Note I started with Pro version this time. Not sure if that was a factor in it working this time.
First off follow the instructions from above to get Wyze talking to Tinycam.
The host and port come from the Tinycam app as mentioned in the instructions. Note the capital I in cameraId.
The value can be found be pulling up the live view of the camera in a browser. The first screen you see when you point your browser to the Tinycam web server is the status / maint screen.
Click on the All Cameras button and you get something like this.
The first cam, the pan version, connected fine but second, a V2, was iffy getting to show in the phone interface, web interface and never did connect to Blue Iris while I was sorting all this. I did move the V2 closer to the AP though and it started working so it might be a WiFi issue. Especially then coupled with its failure to connect in the driveway.
The Samsung Note 4 I was running Tinycam Pro on got hot and the drain on the battery even with the display turned off was high enough the battery ran out after s few hours. After recharging the phone, only running the Tinycam app, removing it from the case and placing it across a pyrex bowl to maximize air flow I got it to run overnight without overheating or the battery going dead.
Lastly it appears Tinycam is pulling from the cloud service which means you will be buring double the external bandwidth that would only be local with a camera with ONVIF or RSTP support.
Update 1/17/2019: After shutting down about everything else on the phone (does not even have sim) and only connecting to one Wyze camera. I noticed Tinycam was offline and when I checked it this is what the phone looked like. Probably lucky it did not burst into flame.
I put in a new battery and placed a temperature monitor with alarm on it. So far it seems OK but keeping a close eye on it. Here is a chart of the temp of the phone vs the room it is in.
In the load chart below it appears there is an upload of around 7-9 Mbps from the 2 cams. There is of course other stuff going on which spikes the upload to 20 Mbps or more and the download is an almost constant 40 Mbps. But again in the dips is a matching 7-9 Mbps load.
Here is a shot of the Tinycam stats screen the second day showing a bit on improvement over the day before.
After a couple days of up and downs I can't say I recommend Tinycam as a bridge or a constant view solution. Though at least some of the problems are probably Wyze related. I had both cams working for awhile the cameras seemed to take turns being offline. I tired installing on Bluestacks which seemed to have similar viewing issues and as far as I can see, no way to make the web server part of Tinycam accessible outside of Bluestacks. I also tried it on my new LG G Pad 2 a lot more powerful than the Note 4. Unfortunately the best I could do was get one camera to connect. I should note here too even the Wyze app was having issues talking to the cams despite signal levels of up to -26 db (99%). In fact I saw more issues with the cam with the stronger signal.
It is basically rooting the camera to convert it to a simple WiFi camera. It is open source and appears to be a simple SD card install.
Note "Set up Wifi in the SD card config folder wpa_supplicant.conf" in the instructions means rename wpa_supplicant.conf.dist to wpa_supplicant.conf then edit it to change SSID and such to match your WiFi network.
However once I did this the camera would no longer connect to WiFi. Seems this is a known issue. After some research on Raspberry Pi blogs I found some dos that said priority=2 is only if you have more than one WiFi you use. removing it seems to have solved it.
I also discovered the demo.bin file is a boot loader altered to look at the SD so you really only have to mess with the holding the button bit the one time. I should also note the OpenIPC version has all the logging stripped out of run.sh so when things go wrong it is impossible to know what happened. So added some back similar to what was in the Dafang hacks and a couple things of my own in mine to help sort things.
On the plus side if all else fails just powering it up without the SD card seems to set it back to where it was when first set it up with your config intact.
Note you need to type in the Video Path and change the RTSP port.
I have not fully tested it yet but it seems like many of the controls do not actually work and or go back to defaults after reboots.
The video stream seems to be 720p no matter what the value Manage->Setting->Resolution are set to.
CPU is really cranking and the cams seems to be running hotter than it did before the new firmware.
It is hard to say how much CPU motion detection is using but given I've seen it hit 100% it does not seem to be worth the overhead.
Lastly night vision does not seem to be working right. Setting Manage->Setting->RTSP->Night Vision to On seems to flip it into night vision mode for a second then it flips back even when it is too dark to see anything unless you turn off IR Cut first. There might a set of clicks that get this working but this would seem to indicate it is not planned to be fixed.
So with the IR Cut on my hall at night with just the light from the bath room looks like this from the Wyze V2.
For comparison here to the view from the kennel looking back the other way.
Which really is not that bad other than the tint. If I turn the lights on in the hall it is not enough to mask the tint though it should be bright enough in the daytime.
Was about to give up on this for the night when I went though the process one last time and this time there was no tint. This it the options I ended up with.
And here is the working night shot.


The EM6354 monitors the supply voltage of any electronic system, and generates the appropriate reset signal. The threshold defines the minimum allowed voltage which guarantees the good functionality of the system. As long as VDD stays above the threshold voltage, the output stays inactive. If VDD drops below VTH, the output gets active. When VDD rises above VTH, the output remains active for an additional delay time. This allows the system to stabilize before getting fully active. A reset signal is asserted after a certain delay time. This delay time, or timeout reset period, can be adjusted using an external capacitor. There are 11 standard threshold voltages between 1.31V and 4.63V for use with a wide range of power supplies. The EM6354 features three output types: active-low push-pull, active-low open-drain and active-high push-pull. The output is guaranteed to be in the correct state for VDD down to 0.8V. The EM6354 is available in SOT23-5 package. It has an operating temperature range from -40°C to +125°C.


text:
var Math_old_random = Math.random;

/**
 * the standard random method replacement, to make it more useful
 *
 * USE:
 *   Math.random();    // original functionality, returns a float between 0 and 1
 *   Math.random(10);  // returns an integer between 0 and 10
 *   Math.random(1,4); // returns an integer between 1 and 4
 *
 * @param min Integer minimum value if there's two arguments and maximum value if there's only one
 * @param max Integer maximum value
 * @return Float random between 0 and 1 if there's no arguments or an integer in the given range
 */
Math.random = function(min, max) {

  if (arguments.length === 0) {
    return Math_old_random();
  } else if (arguments.length === 1) {
    max = min;
    min = 0;
  }

  return ~~(Math_old_random() * (max-min+1) + ~~min);
};

redpajama_set_name: RedPajamaGithub


The Pearl-2 Rackmount Video Production Device from Epiphan is a production video mixer that lets you create visually appealing live video programs by combining, encoding, switching, and recording up to six video sources and two audio sources. Simple to use with a web-based portal for initial configuration, you get a drag and drop interface to create completely customizable layouts for your live stream. You can choose to keep Pearl-2's default encoding settings, or customize them to meet your exact needs. Control the video recorder and video switcher capabilities via the touchscreen or the tablet-friendly Epiphan Live interface. It features a 2 RU rackmount server with all the same functionality as the portable Pearl-2, but designed for installation and operation in a rack.


text:
Manchester City loanee Enes Unal scores impressive brace for FC Twente against Den Haag
The 19-year-old striker has joined FC Twente on loan as he bids to catch the eye of Pep Guardiola away from the Etihad
Manchester City's Enes Unal scores a brace while on loan at Twente
James WhalingSenior Sports Editor
Manchester City loanee Enes Unal is making waves in the Dutch league, and continued his good form with an impressive brace this weekend.
The 19-year-old striker has joined FC Twente on loan as he bids to catch the eye of Pep Guardiola away from the Etihad.
Unal had three goals in his opening three Eredivisie games prior to Saturday's fixture against Den Haag, courtesy of a hat-trick in Twente's 4-3 win at Groningen last month.
And he added another two in their 4-1 mauling of their opponents on Saturday.
The first, in particular, caught the eye, smashing a free-kick home from distance.
Unal will spend the 2016-17 season with Twente (
Michael Dodge / Getty)
The Turk is hoping to catch the eye of Pep Guardiola while he is away (
Reuters)
Pep Guardiola FINALLY starts war of words with Jose Mourinho after thinly veiled "long ball" dig
It rose over the wall before dipping sharply and into the bottom right-hand corner, past the outstretched arm of the goalkeeper.
The Turk signed for City last year after coming through the youth system at Bursaspor, making 35 appearances in the Turkish league.
He had a loan spell with Belgian side Genk last season, before scoring eight times in 11 appearances during a spell with NAC Breda in the Dutch second tier.
Unal will spend the 2016-17 season with Twente.
Will Enes Unal establish himself at Man City?
Manchester City FCFC Twente
Get City news sent directly to your inbox!
BREAKING: UK inflation hits highest level since 1992 as prices rocket for householdsInflation


SURPLUS HEAVEN….IF YOU REALLY LOVE SURPLUS THEN WALKING THIS WAREHOUSE WILL TURN YOU ON.
Here are some pictures from our favorite surplus warehouse. You will see over 200,000 square feet of everything from first quality goods to junk that has not seen the light of day in 30 years. If you would like to get information on any product in these pictures or would like a personal guided tour of this warehouse just call me and we'll get you the information or arrange the visit.


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Stormont County ist ein historischer Bezirk der kanadischen Provinz Ontario. Der Bezirk wurde 1792 gegründet und ging später in die Stormont, Dundas and Glengarry United Counties auf.

Nach ersten Besiedelungen ab 1785 wurde das County 1792 auf einer Fläche von 1,006 km² im Südosten von Ontario am Sankt-Lorenz-Strom gegründet. Einige der ersten Siedler waren der britischen Krone treue Flüchtlinge vor dem Amerikanischen Unabhängigkeitskrieg. Etwa ein Drittel der Pioniere kamen aus dem schottischen Hochland (siehe auch Highland Clearances), ein Drittel waren Deutsche, und der Rest waren Engländer, Iren und Schotten aus dem Tiefland. 1800 wurde Russell County abgespalten.

Weblinks
 Website der United Counties of Stormont, Dundas and Glengarry (SD&G)

Historisches Territorium (Kanada)
Geschichte Ontarios
Stormont, Dundas and Glengarry United Counties

redpajama_set_name: RedPajamaWikipedia


Dow Theory Investment: Dow Theory Update for January 19: Is a secondary reaction about to start for US stocks?
Dow Theory Update for January 19: Is a secondary reaction about to start for US stocks?
Stocks have taken a pause.
On January 12th, 2018 the SPY, Industrials and Transports made their last confirmed closing highs.
Thereafter, The Industrials and the SPY made higher closing highs but the Transports did not confirm.
The longer the Transports do not confirm, the more likely that the current bull swing (not primary bull market) is coming to an end, and that a secondary reaction is about to start. However, we have to wait.
The pullback that got started on September 8th, 2017 has unambiguously setup SLV and GLD for a primary bull market. A quite different issue is whether the signal will be ever given. An in-depth explanation here. Please mind that a "setup" is not the actual signal. SLV made lower lows (of no technical significance under the Dow Theory, though, since it was not confirmed by GLD). For the time being, the primary bear market lows have not been jointly revisited and hence the primary bear market has not been reconfirmed. The longer the non-confirmation persists, the more likely that the primary bear market could be nearing its end. However, we wait until we get a real signal.
As it happened in September 2017, there seems to be growing bullishness around gold. In September, thanks to the Dow Theory, I remained skeptical and I was proven right. Let's see what happens now.
Thus, yesterday, Zero Hedge featured an article entitled "A Golden Opportunity for Precious Metals". The article basically says that gold is about to break above a descending trend-line, and silver is just about to break above a multiyear triangle. Go and read the article.
While the article is technically sound, I'd rather stick to the Dow Theory, if SLV breaks above its triangle, it will also certainly break above the secondary reaction closing high. On the other hand, if GLD breaks above its descending trend-line, it will certainly break above its secondary reaction closing highs. I feel, though, that the patterns of the Dow Theory are more solid, especially when coupled with the principle of confirmation.
In the same bullish vein, GoldCore announces that "Gold may have room to run as Chinese new year looms". Maybe yes, maybe not. I only now that I don't need so much guesswork about the Chinese and gold in order to see a bull market.
All in all, if there is serious bullishness in precious metals both SLV and GLD should break above their respective secondary reaction closing highs, which are highlighted in the charts below with horizontal blue lines. Until this happens, the primary trend remains fully in force.
Until both blue lines are not broken up, there is no primary bull market. Period.
On 11/10/2017 SIL violated its primary bear market closing lows (red arrow on the right side of the chart). GDX has not confirmed. Lack of confirmation implies that the primary bear market has not been reconfirmed, and, as with GLD and SLV, the longer it takes for GDX to confirm the higher the likelihood that the primary bear market may be nearing its end.


Eunice Ribeiro received the MSc degree and PhD degree from the University of Coimbra, Coimbra, Portugal, in 2008 and 2014, respectively. Her research interests include electronic power converters, renewable energies and energy systems.
Bento, F. J. F.; Ribeiro, E. F. F.: ''DC-DC Converters''; Diagnosis and Fault Tolerance of Electrical Machines, Power Electronics and Drives, A. J. M. Cardoso (Editor), , 287-348 pp., IET - The Institution of Engineering and Technology (978-1-78561-531-3), London, UK, 2018.


Many of the following publications are borrowable from, or reference items in, the NDAlibrary . A range of accessibility publications produced by the NDA are available to view on the NDA website.
Many of the books and articles in the General section investigate and report on design methodologies that can be incorporated into the development of ICTs, products, services or buildings.
Story, M.F., Mueller, J.L., Mace, R.L.
The Universal Design File is available to download from the North Carolina State University (NCSU) Centre for Universal Design (CUD) website.
Clarkson, J., Coleman, R., Keates, S., Lebbon, C.
An edited excerpt of a presentation made by Ronald L. Mace, FAIA, at Designing for the 21st Century: An International Conference on Universal Design on June 19, 1998.
A Perspective on Universal Design is available on the North Carolina State University (NCSU) Centre for Universal Design (CUD) website.
Iwarsson, S., Ståhl, A. (2003).
Accessibility, usability and universal design positioning and definition of concepts describing person-environment relationships is available online to NDA library users.
Design for All : Socially Responsible Design or Just Good Sense?
Darzentas, J.S. and Darzentas, J. (2004).
Proceedings of ETHICOMP2004 Challenges for the Citizen of the Information Society , pp. 237-249. Syros, Greece.
The abstract of Design for All : Socially Responsible Design or Just Good Sense? is available on the ETHICOMP 2004 conference website.
"A Report for the Ministry of the Environment, Government of Norway." The Centre for Universal Design, North Carolina State University, North Carolina.
Universal Design — Clarification and Development (PDF document, new window) is available to download at the Norwegian Ministry for the Environment website.
Keates, S., Lebbon, C. and Clarkson, P.J. (2000).
Proceedings of RESNA 2000 Conference, pp. 276-278, Orlando, Florida.
Investigating Industry Attitudes to Universal Design is available on the RESNA 2000 conference website.
This series of 10 booklets provides comprehensive best practice guidance on how to design, build and manage buildings and spaces so that they can be readily accessed and used by everyone, regardless of age, size ability or disability.
See the General section above for more publications on product design.
INNOVATION, the Quarterly Journal of the Industrial Designers Society of America (IDSA), Volume 16, No. 1 1997.
Mining our natural resources is available to read online on the International Council of Societies of Industrial Design website.
Thatcher, J., Burks, M. R., Heilmann, C., Henry, S.L., Kirkpatrick, A., Lauke, P. H., Lawson, B., Regan, B., Rutter, R., Urban, M., Wadell, C.
Klironomos, I., Antona, M., Basdekis, I., and Stephanidis, C. (2006).
Universal Access in the Information Society, 5: 105-119.
White Paper: Promoting Design for All and e-Accessibility in Europe is available from the NDA library.
Law, C.M., Yi, J.S., Choi, Y.S. and Jacko, J.A. (2008).
Universal Access in the Information Society, 7:31-54.
Universal Access in the Information Society, 7:55-77.
See the listing of award schemes.
See the listing of Universal Design Centres.


text:
EXCLUSIVE: 60 Minutes with Eric Williams
Veronike Collazo
Loudoun County School Superintendent Talks Budget, Vision.
Earlier this week, The Tribune's editorial staff met with Loudoun County's Superintendent of Public Schools (LCPS) Eric Williams for an hour-long conversation about the county's public school system and his role as its staff leader.
LCPS is the third largest school division in Virginia, and enrolls more than 79,000 students in 89 facilities. Those includes 15 high schools, 15 middle schools, 57 elementary schools and three special purpose schools.
Student enrollment continues to rise at a steady pace, but demographics are changing quickly. Just over 50 percent of students are non-white, and the 20.3 percent captured in the segment designated as Asian (including Asian, Middle Eastern and Indian-identified students, among others), is the fastest growing population, according to current LCPS statistics.
With budget season in full swing, Williams reviewed his priorities in crafting the proposed FY 2018 budget that is being reviewed by the county School Board. He also commented on the more publicized items in the budget, other LCPS issues in the news, and his first two-and-a-half years on the job.
Joining Williams was Assistant Superintendent of Business and Financial Services Leigh Burden and Public Information Officer Wayde Byard.
What's your style when it comes to presenting the proposed annual budget of LCPS?
WILLIAMS: I would say that three budget principles reflect the style. One is the success mentality, two is strategic and three is being transparent. In terms of success mentality, it's about how can we take our high performing division and take it to the next level. Rather than having a "woe is me" attitude toward financial limitations, it's saying, in terms of available funds, how can we take that and continue to improve, instead of just having a "let's just keep the ship afloat" attitude.
The second aspect is being strategic. This involves questions about the proposed budget reflecting priorities but also considering different ways to spend the same dollar in order to get a bigger bang for our buck. In this year's proposed budget, like in the past two years, we've done reallocations. And it's not saying the things we had been spending the money on aren't worthwhile, it's really a question of how might we spend it differently if we're taking a step back.
The third part that I think has been appreciated by the school board, board of supervisors and the community, is being transparent and giving a lot of detail. The biggest example of that are staffing standards. Previously there was always a rationale for how we're going to spend the money (and) this is how we will approach staffing schools. Now we have articulated staffing standards that say for every certain number of students at a particular school we're going to provide this number and type of staff. When we say we've got 3,000 more students, you can look and see how many counselors and others are generated by that number of additional students.
Recruitment and retention of bus drivers is highlighted in your budget. Why is it such a problem?
WILLIAMS: We have not been able to fill all of the vacancies. It's not just the rate of pay, it's also the number of hours. You might have a decent rate of pay, but if you're only working four hours, that's not going to be as attractive a compensation package as working six hours a day.
We are reducing the number of bus driver positions, and people may say, "Hey wait, if you need more bus drivers, why are you reducing some?" We do need more, but not as many as are budgeted so we're reallocating some budgeted but unspent money to have a more attractive compensation package in order to fill those positions. Generally speaking, it's not that our current scale is way below what other localities are offering. Other localities are struggling too.
Your budget presentation acknowledges disciplinary disparity in Loudoun's schools. Are there more problems among certain populations, or is there a disparity in how they are disciplined? Or both?
WILLIAMS: We have one of the lowest suspension rates across the state. In fact, the state has cited us as examples to other divisions. Now that being said, there are still disparities that exist in Loudoun County that reflect disparities throughout the state and throughout the nation.
It's hard to reach a conclusion one way or the other but regardless of which of those situations it is or some combination thereof, we believe there are interventions such as restorative practices, and positive behavior intervention and support (PBIS) that can reduce the overall suspension rate for students regardless of any disparities that exist. Even if you can't attribute it to one or the other, we still want to implement practices to try to address the overall situation.
Inclusive practices is one of your stated goals. With that in mind, how did you react to the recent School Board vote on LGBTQ protections, and how has the national political mood affected the climate in Loudoun's schools?
WILLIAMS: Multiple school board members expressed interest in following this issue as it plays out in the judicial system. Obviously different school board members have different perspectives, but my sense is that the school board is in a wait and see mode.
School climate is incredibly important because when there's a positive, safe, trusting environment with positive relationships among students, among teachers and between students and teachers, that serves as a foundation for being academically engaged — and, ultimately, for academic achievement.
I would say regardless of who a student is or what a potential bullying or discriminatory action is, we want to have a climate that is safe and supportive for all students.
Reflecting the nationwide tension, there have been situations in which inappropriate comments were made that don't meet our expectations for how you treat another person in a respectful, positive way. We're not saying every day has to be a kumbaya moment, but there are certain norms you have to meet in terms of how you interact.
The point isn't that we need to protect one group of students as victims against inappropriate comments from one group of people with one set of political principles. It works across the political perspective. People can say inappropriate, ridiculous things even though they hold political viewpoints across the whole spectrum, so upholding these norms of civil interaction is really apolitical.
What's your view on the siting and construction of new schools in developed areas of Loudoun where space is limited and traditional footprints won't work?
WILLIAMS: Even though the percentage model of growth has decreased, because we have such a large base population, the raw number remains very large — over 3,000 additional students yearly — and that trend will continue for years to come. Because of that, we need additional schools and we're continuing to build at least one a year for the foreseeable future.
In terms of the construction of metro stations as a part of that process, there have been discussions of a possible new school design. We are very early in that process. I see our role as staff members making clear options available to the School Board, and then for the school board to communicate with the Board of Supervisors.
Important questions exist, such as can you have a multi-story building? If so, what are the implications going to be for instruction? What other ancillary services and opportunities are going to exist? Take, for instance, playing fields. If you have a school by the metro, is it going to have the same square footage for the building itself and acreage of fields? I would anticipate having a work session later this spring on the topic for the school board and county staff.
When it comes to effective budgeting, what's a recent LCPS success story that you're especially proud of?
WILLIAMS: The most important point I would make is that what's being proposed is a prioritized list of what's needed to sustain our excellence and to build on it.
I would cite full day kindergarten as an example of that. In my first year here, we proposed a moderate, steady expansion. We need to have a sense of urgency on one hand, but on the other hand, it's not just a matter of throwing a ton of money at the operating and construction budget. We're building six classroom expansions to add space because it's not just about using existing space, but we didn't want to over-recommend school space that we wouldn't need.
We've moved from 11 percent of kids being in full day kindergarten my first year here to a little over 30 percent last year, we're a little over 50 percent this year. I've proposed being at 82 percent and the School Board is discussing if they're going to fully fund that amount or look at something slightly less.
I cite that as a general example of steady, reasonable progress. And a part of that is constantly saying, what are we going to stop spending money on? We identified over $5 million in operating budget and a number of positions we could cut in order to make this a more reasonable request.
Issues of teenage depression, drug use, overdoses and suicide are the talk of the nation. What new efforts are underway or planned to address these issues in Loudoun's public schools?
WILLIAMS: The proposed budget would include a significant additional emphasis on mental health, and it's not so much as doing things differently as it is doing more of it. We already promote mental wellness and resiliency, and there are efforts to connect students and their families with services that exist in order to receive mental health treatment. We also want to provide social and emotional support.
What we've proposed is creating unified support teams for high school students that would include a variety of professionals. It's a total of 25 additional positions — five psychologists, eight social workers, eight school counselors, two supervisors and two student assistant specialists. I give credit to Mary Kealy, the Assistant Superintendent of Pupil Services, because she has identified funds within existing Pupil Services budget that would pay for this expansion.
Budget is only part of it. Staff support and protocols are also an important part, and in the past year there have been additional training opportunities for staff members. Pupil Services also does a series of speaking engagements, and our staff is speaking about suicide prevention at Broad Run High School on Feb. 2. We've got hundreds of people who are coming.
It's also a matter of tapping into existing community resources. I'm thrilled that in the next two years all of our high school students will have the opportunity to see the production of A Will to Survive by the Same Sky Project. There's also a middle school version that relates to themes of resilience and inclusivity. I had the opportunity to see it, and it's powerful.
We explicitly want to leverage that peer support, so we have staff members within the Department of Pupil Services who pull students from every high school to come together and strategize on climate issues, because it's one thing for adults to encourage help-seeking behavior; it's another thing for students to believe in these situations you really need to talk to a professional.
How do you view your personal transparency when to comes to accessibility and accountability to Loudoun residents?
WILLIAMS: I think that at a practical level, sharing information is important because it provides context and understanding for decisions. Take for example the budget, taking the time to say to people, here are the details about how we're spending the money we say is needed for enrollment growth is going to end up benefiting kids because we're more likely to receive the resources that we need because people have the information they need to make judgements.
Now, transparency is kind of like motherhood and apple pie, it's hard to be against it in the abstract. The frustrating aspect of it is sometimes there are restrictions that might prevent one from sharing information, such as it being a personnel matter as an example. But at a practical level, being transparent and providing information can be incredibly beneficial.
Many people are not happy about the way LCPS has handled the ongoing matter related to Principal John Brewer of Dominion High School. If you had to do it over, would you do anything differently?
WILLIAMS: Any time a staff member is on leave, that can be very difficult for everybody involved — students, parents and colleagues, and we shared that acknowledgement with our recent statement. I recognize that in my position as superintendent, I'm going to come under criticism at times. I just need to not take it personally while at the same time recognizing how difficult it is for everybody involved. So it's important we handle the situation appropriately.
I won't comment on individual situations, I will just say that generally speaking, I understand that even when we're sharing the information we're able to share, some people won't perceive that it's sufficient and I understand that.
What's most important to you in doing the job of school superintendent?
WILLIAMS: I would say a key aspect of a superintendent's job is creating a shared vision. Yes, a superintendent needs to set forth ideas that can become an important part of a vision, but in order for a vision to be adopted by people it also needs to be adapted by people.
That vision relates to instructional matters and also to development of the budget. Trying to create a shared commitment to those three budget principles mentioned earlier, for example.
And it's with a variety of stakeholders, not just the School Board. It's with parents, business leaders, not for profits, staff members. But obviously a key part of the superintendent's job is working with the School Board and giving it the opportunity to be a high impact governance team. By that I mean an effective superintendent doesn't just come and ask a board to rubber stamp things, but gives board members the opportunity to have a major influence through policy, budget, strategic planning, and accountability measures within the strategic plan.
That relationship is a collaboration, I call it a team of 10. There's the nine school board members and the superintendent. Now, school board members have different roles, collectively, and they're my boss. But the ten member team is still a team approach.
Is there too much of a test-prep mentality in Loudoun's schools?
WILLIAMS: In saying we need to avoid a test-prep mentality, I still believe studying and test results are important. But it's also a broader notion. We work with community members in setting forth our profile of a LCPS graduate, saying that our graduates will be knowledgeable, so they'll know important content. They'll also be effective collaborators, communicators, creators of solutions and contributors to the world.
We're not just prepping students to do well on the test, but to help graduates make contributions to the world through careers, civic engagements and community service.
All of that are important aspects to the instructional vision. Another part is having a team of high-performing professionals. One of the big ideas of how we're going to do that is stay focused on the type of graduate we want to create. To want to have professionals and cultivate them very strategically. And to have efficient and effective operations.
Of course you want efficient and effective operations, but the devil's in the details to make that occur on a day-to-day basis. We want to be good stewards of taxpayer resources in terms of efficiency, but we also want results. I'll cite transportation as an example. We're not where we want to be in terms of efficiency and effectiveness, and so we're not just going to accept that situation; we're going to work to improve upon it.
The Loudoun NAACP has criticized the lack of diversity among LCPS teachers. You recently created a position specifically focused on diversity in recruitment. How is that going?
WILLIAMS: It's still early to see all the fruits of our most focused recruitment efforts this year, but what I would point to is just the fact that we have focused recruitment and part of that is to diversify the teaching workforce and having one that more closely reflects the demographics of our student population.
In terms of some of the steps that have been taken, we've expanded the number of historically black colleges that are visited in recruitment efforts, and having targeted recruitment events in particular areas. We had an event in Sterling schools where we brought in candidates who expressed particular interest in working at a diverse school, giving them a chance to visit the schools during the day so they can see if this is a place where they'd like to work.
High touch recruitment efforts are also part of this, so basically more candidate care for folks instead of being a bureaucratic entity during the recruitment process. And all of our hiring managers — principals, assistant principals, folks at the division level — participate in implicit bias training.
All that was all done last fall, but we're going to want to see how things play out between now and next fall with recruitment efforts, and the new budget does propose an additional position specifically for recruitment.
Besides progress on full day kindergarten, what else is a highlight of your first 30 months on the job?
WILLIAMS: I would say the shift toward deeper learning and giving students the opportunity to engage in trying to solve authentic problems rather than just prepare for a test. I'm pleased with our work on that. I'm also pleased with how staff has embraced the three budget principles because I think that's important.
In terms of the strategic plan, it's having a plan with three main goals and about 15 strategic actions underneath those including increasing salaries.
And on the salary side, we recognize there's a lot of work still to be done, especially to attract and keep mid-range salaried teachers. But we've already made significant improvements in the teaching salary schedule.
How does it feel to be superintendent of Loudoun County public schools?
WILLIAMS: I absolutely love it, because even though it's a high-performing school division, people don't want to rest on their laurels. They constantly have an attitude of "let's do an even better job".
Ryan Butler and Tom Julia of The Tribune also participated in the interview of Superintendent Williams.
Loudoun County School Board


text:
1902 England v Australia - Test Series
Australia Won Series 2-1
Date Match Ground / Location Result
29/05/1902 1st Test: England v Australia Edgbaston, Birmingham Match drawn
12/06/1902 2nd Test: England v Australia Lord's, London Match drawn
03/07/1902 3rd Test: England v Australia Bramall Lane, Sheffield Australia won by 143 runs
24/07/1902 4th Test: England v Australia Old Trafford, Manchester Australia won by 3 runs
11/08/1902 5th Test: England v Australia Kennington Oval, London England won by 1 wicket
Batting and Bowling Analysis for Series
Series Records and Statistics Menu


Date : 24th August 2015.
CURRENCY MOVERS OF 21th August 2015.
The risk-off theme continues in global financial markets as traders re-price the USD in view of the reduced chance that the Fed will begin tightening rates in September. The EURUSD is now trading near multi month highs around 1.15 after accelerating through my 1.1260's target area; see my August 14 report, current price is starting to look overbought ahead of the 1.1530 resistance level. EURUSD traders should watch if price can hold above the 1.1436 support level before initiating new longs, otherwise a break below the 1.1430's could open up the possibility for a set-back towards the 1.1216 – 1.1189 levels ahead of an advance on the 1.16's.
German property prices continue to rise, with prices for apartments rising by around 1.4% m/m. The overall index rose 0.73% m/m and up 5.3% y/y. Low interest rates and a robust labour market are driving up property prices, but while the Bundesbank is keeping a close eye on developments it is not seeing signs of a serious property bubble at the moment, even if prices in key cities are already overvalued.
Asian and emerging market currencies are under pressure, along with commodity related currencies such as the AUD and the CAD as the FOMC minutes showed a Committee divided, the minutes gave no clear signals on the timing of a rate liftoff, however the mention of risks from China, the growth/inflation impacts of a stronger dollar, and a downgraded inflation outlook from the Fed Staff resulted in a downbeat market interpretation. China will remain a focal point as Chinese officials struggle with a slowing economy and falling equity market.
Current 5 day percentage change of currencies against other major currencies since the daily close 23:59:59 server time, 5 days ago.
The AUD is trading lower as the spill-over from the turmoil in China's stock markets remain a risk factor for the AUD. The JPY is trading higher as talk of further easing to stimulate growth continues to gain momentum.
The EUR over the last five trading days is stronger as the current sell off in the Chinese stock markets and weak commodity prices may have the market rethinking a US rate move in September.
• USD FOMC Member Lockhart Speaks: Federal Reserve Bank of Atlanta President Dennis Lockhart is due to speak today.


text:
Q: Active Directory in the cloud My company is considering implementing Active Directory and Windows Server to manage our local network and workstations.  The main benefits sought are central management of machines, security policies, and roaming profiles.
When using Windows Server for these purposes, does it ever make sense to run Windows Server from the cloud (i.e. Rackspace), or must it always be run locally?

A: You can do this. Were I you, I would only do this if :

*

*You had no need for local servers, at all.

*Your internet connection was rock-solid.

A: Roaming user profiles are going to be painful to use via the Internet. Any significant number of files in folders (which the AppData folder is notorious for having) is going to cause painful delays in profile synchronization during logon and logoff. Due to the way profiles are copied (file for file) latency will impact this, though as long as you're using SMBv2 the latency won't have as large an effect as it would on SMBv1 clients.
You're also going to see potentially long boot and logon times relating to the application of Group Policy if the latency between your computers and your domain controller is significant. There are a lot of round-trips during the Group Policy application process. Latency is going to be the killer on this, not bandwidth.
The last few users who logged-on recently will be able to logon to a client computer even w/o Internet connectivity (provided you leave the default cached credentials settings in clients alone). If you have users moving around between machines or attempting to logon to computers they've never used before (a "hot desk" environment, more users than computers, etc) then you might see problems with logon in times when the Domain Controller computer isn't reachable.
I've gotten a number of requests recently from people on the 'net to have me help them with this kind of thing and, frankly, I don't understand the payoff, considering that you already have PCs attached to a LAN. (I could, potentially, see a payoff in a company that is "born" in a totally geographically distributed fashion, but that's a whole different rant.)
The amortized cost of a small server computer and Windows licenses over, say, a 3 year lifetime should be vastly less than the sum of the aggregate expense for hosting a server in the "cloud" over the same time period. You'd either need to pay the "cloud" provider, a contractor, or an employee for Active Directory and server administration in any situation, so "the cloud" doesn't magically make that expense go away.
There's also backup and disaster recovery to worry about. Just because the server is in "the cloud" doesn't mean it's backed up and, if it is, that doesn't mean those backups are geographically distributed and stored offline. Finally, there's the whole security concern associated with having your Active Directory sitting outside your firewall where you may not have as granular control of network filtering policies, and certainly a much higher chance for denial of service attacks.
Personally, I'd rather have a low cost server computer sitting on my LAN and a VPN (DirectAccess, preferrably) for clients to use while off-site than having the server off-site. I'd feel a lot more comfortable storing a reasonable quantity of data locally than in "the cloud" (using "the cloud" for backup, versus primary storage, isn't what I'm talking about here).
For comparison's sake: I'd expect a low-end Dell 1U rack mountable server w/ a pair or small (250 - 500GB) SATA or nearline SAS drives in a RAID-1 configuration and with a 3 year next-business-day warranty, running Windows Small Business Server Essentials 2011, to cost somewhere in the vicinity of $2,250.00  to $2,500.00.
At $3,000.00 (building in a little "fudge factor") that gives a monthly amortized expense of $83.33 to purchase the machine and the software and run it for the life of its warranty.
Edit:
Using a simple word like "cloud" as a kind of "magic pixie dust" seems to make people forget the complexity associated with hosting server computers. When you outsource your reasonably simple small office server to a "cloud provider" you're causing your simple small office server to become a much more complex offering (assuming the hosting provider is taking advantage of an economy of scale and leveraging their hardware and network connectivity across their entire Customer base). Your needs stay the same when you outsource that server to "the cloud", but the provider shoulders the burden of making a much more complex system than a small office server work to keep your needs met. You get all the advantages of a small office server combined with all the risks of a large distributed system!
Whenever I read "the cloud" in marketing literature I substitute a phrase for those words. When I read "Hosting our email in the cloud", for example, I really see "Hosting our email in servers reachable over a network with unpredictable latency and bandwidth and no guarantee on connectivity, in a physical environment I don't control, on hardware of unknown quality or maintenance, that could potentially become inaccessible at any time based on the whims of others."

A: I don't see any problem with this, but you should have a peered DC at each site. Having the PDC on a VPS may actually make a lot of sense (better SLA than locally hosted servers). I think you will want to have everything over a secure channel, some sort of IPSEC VPN.
Make sure you consider AD Site configuration.
Use DFS for roaming profiles and/or replication of common files.
Having done the above there is no need for a fast internet link.

redpajama_set_name: RedPajamaStackExchange


Dr. Shuman discusses the importance of oral health in geriatric medical care and the information and resources available from the Gerontological Society of America's Oral Health Initiative. Today's Geriatric Medicine, January-February 2018.
The Walker Methodist Health Center was honored with a 2016 LeadingAge Award for its partnership with the University of Minnesota School of Dentistry in establishing the Walker Methodist Dental Clinic.


What happens if I dial this number? What happens if I play this tone?' They were simply curious." Related Story The Definitive Story of Steve Wozniak, Steve Jobs, and Phone Phreaking Few capture this sense of wistful curiosity better than 'Captain Crunch'. - Whatever Happened to the Phone Phreaks?
Discuss anything about the word wistful below. Improve your vocabulary. Ask experts and help others learn new words. Prepare for exams like GRE, CAT, GMAT, Bank PO, GATE, SAT and others. Learn English as a second language.


text:
\section{Introduction}

SLAM solves the problem of mapping unknown environments while estimating robot state. Though SLAM is actively researched for the past few decades, Cadena et al. \cite{pastPresent} note that there are still challenges in handling diverse environments and long-term continuous operations. SLAM systems operate on a wide range of sensor modalities each trying to exploit their benefits. In the past few years, LiDAR based SLAM systems have gained popularity over vision based systems due to their robustness to changes in the environment. However pure LiDAR based systems have their deficiencies. They fail in environments with repeating structures like tunnels or hallways. These environments are challenging to map and localize, and system which exploits the strengths of all the sensor modalities need to be deployed to succeed. We propose VIL-SLAM, which uses IMU, stereo cameras and LiDAR, and exploit their benefits collectively. Our experiments demonstrate that VIL-SLAM performs on par with pure LiDAR based systems in most cases and better on cases where pure LiDAR based systems simply fail. VIL-SLAM achieves this by integrating stereo VIO and LiDAR mapping with loop closure. To the best of our knowledge, this is the first work of this kind. In addition, we introduce a method to evaluate mapping results using a time-of-flight laser scanner (Faro). We also provide VIO validation results on the EuRoC MAV dataset.

VIL-SLAM uses a tightly-coupled stereo VIO that performs fixed-lag pose graph optimization, LiDAR mapping that uses sparse 3D features for map registration, and loop closure that integrates sparse point cloud alignment with visual loop detection. Loop closure optimizes a global pose graph using an incremental solver. VIL-SLAM is designed to operate long term and in different environments robustly. The high frequency IMU measurements produce estimates which are reasonable for the short interval but quickly drift. When constrained with stereo visual measurements, we can correct the biases and estimate accurate relative motion (referred to as VIO). The relative motion estimate is used to aid LiDAR scan matching which then accumulates the high-fidelity 3D point clouds to form an accurate map. The robot's state estimate accumulates drift during long traversals. Loop closure addresses this issue by recognizing the revisited sites using either visual or LiDAR methods. Visual methods involve using Bag-of-Words \cite{refBoW} to recognize the place and Perspective-n-Point (PnP) algorithm to estimate the pose correction. In LiDAR methods, the places are recognized using segment based algorithms like SegMatch \cite{segMatch}, and pose correction is estimated using Iterative Closest Point (ICP) \cite{121791} algorithm. While the Bag-of-Words method is fast and versatile, it lacks the accuracy of the slow but robust LiDAR method which uses ICP. VIL-SLAM uses a hybrid approach where it first finds the loop closure candidate using Bag-of-Words technique, generates a rough estimate of the pose correction using Perspective-n-Point (PnP) algorithm, and then refines the rough estimate using ICP.

\begin{figure}[t!]
    \centering
    \includegraphics[scale=0.145]{platform.png}
    \caption{(a) Experimental platform built. (b) Mapping result from an outdoor test. Streetlight is reconstructed clearly.}
    \label{platformFig}
    \vspace{-2mm}
\end{figure}

\begin{figure*}[t!]
    \centering
    \includegraphics[scale=0.5]{system_overview3.png}
    \caption{The system diagram of VIL-SLAM. Sensors are in gray and modules are in green. Arrows indicate how messages flow within the system. The dark thick arrows indicate the system real-time output and the light thick arrow indicates the output generated in post-processing near real-time.}
    \label{system_overview_block_diagram}
    \vspace{-4mm}
\end{figure*}

\section{Related work}\label{secRW}
Current VIO literature introduces various formulations to integrate visual and inertial data. The literature characterizes different approaches into \textit{tightly-coupled system} \cite{refVINSMONO, refOKVIS, Hsiung18iros}, in which visual information and inertial measurements are jointly optimized, or \textit{loosely-coupled system} \cite{refDSO, refPTAM, ARMMFA, RTOVI}, in which IMU is a separate module and fused with a vision-only state estimator. The approaches could be further divided into either filtering-based \cite{refRSVIOupenn, ref11, refROVIO, Wu2015ASR, RTOVI, 6385458} or graph-optimization based \cite{refVINSMONO, refOKVIS, Hsiung18iros, Indelman2013InformationFI, DVISO}. Tightly-coupled optimization-based approaches, taking the benefit of minimizing residuals iteratively, usually achieve better accuracy and robustness with a higher computation cost. In our work, we bound the computation cost by forming landmarks in a structureless fashion and only optimizing for a fixed-size pose graph to achieve the real-time performance.

Current state-of-the-art SLAM systems using just laser scanner are \cite{7353456, 7487648, 7279468, refLOAM, IMLSSLAM}, in which a motion model is required, either a constant velocity model or a Gaussian process. Approach in \cite{6907626} combines stereo cameras and a laser scanner. It has motion estimation generated from a visual odometry (VO) and refined by matching laser scans. The differences to our system are that they use multi-resolution grid map representation and ours uses sparse point cloud to localize and outputs dense point cloud. Also, VIO is usually more robust and accurate compared to a VO \cite{Delmerico2018ABC}. VLOAM \cite{refVLOAM}, which uses an IMU, a monocular camera, and a laser scanner is the most similar existing system to ours. One difference is that we use a tightly-coupled VIO as the motion model to initialize the LiDAR mapping algorithm whereas VLOAM uses loosely-coupled IMU and camera. Though our VIO is more robust, VLOAM has a more interactive system where information from both camera and LiDAR module could be used for IMU biases correction. One addition that VIL-SLAM has is the LiDAR enhanced loop closure.

\section{System overview}\label{secSO}
The system has four modules as shown in Fig. \ref{system_overview_block_diagram}. The visual frontend takes stereo pairs from the stereo cameras. It performs frame to frame tracking and stereo matching, and outputs stereo matches as visual measurements. The stereo VIO takes stereo matches and IMU measurements, performs IMU pre-integration and tightly-coupled fixed-lag smoothing over a pose graph. This module outputs VIO pose at IMU rate and camera rate. LiDAR mapping module uses the motion estimate from the VIO and performs LiDAR points dewarping and scan to map registration. The loop closure module conducts visual loop detection and initial loop constraint estimation, which is further refined by a sparse point cloud ICP alignment. A global pose graph constraining all LiDAR poses is optimized incrementally to obtain a globally corrected trajectory and a LiDAR pose correction in real-time. They are sent back to LiDAR mapping module for map update and re-localization. In post processing, we stitch the dewarped LiDAR scans with the best estimated LiDAR poses to have the dense mapping results (Fig. \ref{traj_map_res}).

\section{Visual frontend}\label{secVF}
Visual frontend accepts a stereo pair, and performs frame to frame tracking and stereo matching for the generation of a set of stereo-matched sparse feature points, namely, stereo matches. A stereo match could either be one tracked from previous stereo pair, or a new one extracted in this pair. The frame to frame tracking performance directly affects the temporal constraints quality while the stereo matching helps constrain the scale. These two tasks are crucial for any stereo visual odometry. Direct methods show robust and efficient temporal tracking results in recent years \cite{refDSO, refSVO}. Thus, we use Kanade Lucas Tomasi (KLT) feature tracker \cite{refLKT} to track all feature points in the previous stereo matches, either in the left or right image. Only when they are both tracked, we have a tracked stereo match and it is pushed into the output. Large stereo baseline helps scale estimation and reduces degeneracy issues caused by distant features. We use feature-based methods which are better suited to handle large baselines than KLT. If the number of tracked stereo matches is below a threshold, we perform feature extraction using Shi-Tomashi Corner detector \cite{refSHI}, followed by a feature elimination process in which features that have pixel coordinate distance to any existing features smaller than a threshold are deleted. ORB (Oriented FAST and Rotated BRIEF) \cite{refORB} descriptors are then computed on all survived features, followed by a brute-force stereo matching to obtain new stereo matches. The system initializes by performing stereo matching on the first stereo pair.

\section{Stereo visual inertial odometry}\label{secSVIO}
The goal of the stereo VIO is to provide real-time accurate state estimate at a relatively high frequency, serving as the motion model for the LiDAR mapping algorithm. A tightly-coupled fixed-lag smoother operating over a pose graph is a good trade-off between accuracy and efficiency. Optimization-based methods in general allow for multiple re-linearization to approach the global minimum. A fixed-lag pose graph optimizer further bounds the maximum number of variables, and hence the computation cost is bounded. Since bad visual measurements cause convergence issues, we enforce a strict outlier rejection mechanism on visual measurements. The system eliminates outliers by checking the average reprojection error, both stereo and temporal.

The VIO proposed has \textit{IMU Pre-integration Factor} and \textit{Structureless Vision Factor} as constraints. The graph representation is shown in Fig. \ref{VIO_pose_graph}. Variables to be optimized are the states inside the window. Denote $\textbf{S}_t$ as the state variable at the stereo frame time $t$. $\textbf{S}_t$ contains the 6 Degrees of Freedom (DoF) system pose $\xi_t$ (IMU frame), the associated linear velocity $\textbf{v}_t$, accelerometer bias $\textbf{b}^a_t$, and gyroscope bias $\textbf{b}^g_t$. The window of state variables being estimated are of the most recent $N$ stereo frames. Past state variables are marginalized, producing prior factors on related variables.

\begin{figure}[t!]
    \centering
    \includegraphics[scale=0.18]{vio_pose_graph.png}
    \caption{Fixed-lag pose graph formulation in the VIO. State variables being optimized are circled, where $i$ stands for the current state and $N$ is the window size. (a) The state to be marginalized is crossed. (b) After marginalization, prior factors are added back on related variables.}
    \label{VIO_pose_graph}
    \vspace{-2mm}
\end{figure}

\subsection{IMU pre-integration factor}

We follow the IMU pre-integration method \cite{refIMUPre}\cite{refIMUPre0} to generate relative IMU measurements between $\textbf{S}_i$ and $\textbf{S}_j$. Using the pre-integration technique, re-linearization could be performed efficiently during optimization. The residual represented by the IMU pre-integration factor is $\textbf{r}^I_{ij}$, which consists of three terms: the residual of pose ($\textbf{r}_{\Delta\xi ij}$), velocity ($\textbf{r}_{\Delta\textbf{v}ij}$), and biases ($\textbf{r}_{\Delta\textbf{b}ij}$).

\subsection{Structureless vision factor}
Visual measurements are modeled in a structureless fashion, similar to \cite{refIMUPre}\cite{refIMUPre2}\cite{refIMUPre3}. Consider a landmark $p$, whose position in global frame is $\textbf{x}_p\in\mathbb{R}^3$, is observed by multiple states and denote the set of states observing $p$ as $\{\textbf{S}\}_p$. For any state $\textbf{S}_k$ in $\{\textbf{S}\}_p$, denote the residual formed by measuring $p$ as in the left camera image as $\textbf{r}^V_{\xi_{k,lc},p}$ ($\xi_{k,lc}$ is the left camera pose, obtained by applying a IMU-camera transformation to $\xi_k$):
\begin{equation} \label{visualResidual}
    \textbf{r}^V_{\xi_{k,lc},p} = \textbf{z}_{\xi_{k,lc},p}-h(\xi_{k,lc},\textbf{x}_p)
\end{equation}
where $\textbf{z}_{\xi_{k,lc},p}$ is the pixel measurement of $p$ in the image and $h(\xi_{k,lc},\textbf{x}_p)$ encodes a perspective projection. Same formulation is derived for the right camera image. Iterative methods are adopted for optimizing the pose graph, and hence linearization of the above residual is required. Equation (\ref{linearizedVR}) shows the linearized residuals for landmark $p$.
\begin{equation}\label{linearizedVR}
    \sum_{S_p}||\textbf{F}_{kp}\delta \xi_k + \textbf{E}_{kp}\delta\textbf{x}_p + \textbf{b}_{kp}||^2
\end{equation}
where the Jacobians $\textbf{F}_{kp}$, $\textbf{E}_{kp}$ and the residual error $\textbf{b}_{kp}$ are results from the linearization and normalized by $\Sigma^{1/2}_c$, the visual measurement covariance. Stacking each individual component inside the sum into a matrix we have
\begin{equation}
    ||\textbf{r}^V_p||^2_{\Sigma_C} = ||\textbf{F}_{p}\delta \xi_k + \textbf{E}_{p}\delta x_p + \textbf{b}_{p}||^2
\end{equation}
To avoid optimizing over $\textbf{x}_p$, we project the residual into the null space of $\textbf{E}_{p}$: Premultiply each term by $\textbf{Q}_p\doteq\textbf{I}-\textbf{E}_{p}(\textbf{E}_{p}^\top\textbf{E}_{p})^{-1}\textbf{E}_{p}^\top$, an orthogonal projector of $\textbf{E}_{p}$ \cite{refIMUPre}. We thus have the \textit{Structureless Vision Factor}, for landmark $p$ as
\begin{equation}
    ||\textbf{r}^V_p||^2_{\Sigma_C} = ||\textbf{Q}_p\textbf{F}_{p}\delta \xi_k + \textbf{Q}_p \textbf{b}_{p}||^2
\end{equation}
\subsection{Optimization and marginalization}
Given the residuals, the pose graph optimization is a \textit{maximum a posteriori} (MAP) problem whose optimal solution is
\begin{equation}
    \textbf{S}^*_w = \arg\min_{S^*_w}(||\textbf{r}_0||^2_{\Sigma_0} +\sum_{i\in w} ||\textbf{r}^I_{i(i+1)}||^2_{\Sigma_{I}} + \sum_{p}||\textbf{r}^V_p||^2_{\Sigma_{C}})
\end{equation}
where $\textbf{S}^*_w$ is the set of state variables inside the window. $\textbf{r}_0$ and $\Sigma_0$ are prior factors and their associated covariance. $\Sigma_I$ is the covariance of the IMU measurements. We use the Levenberg-Marquart optimizer to solve this nonlinear optimization problem. The most recent $N$ state variables are maintained inside the optimizer. Schur-Complement marginalization \cite{schurComplement} is performed on state variables getting out of the window. Prior factors are then added to related variables inside the window as in Fig. \ref{VIO_pose_graph}(b).

\begin{figure}[t!]
    \centering
    \includegraphics[scale=0.18]{global_pose_graph.png}
    \caption{The global pose graph consists of the \textit{LiDAR Odometry Factor} and the \textit{Loop Constraint Factor}. $i$ stands for the current scan.}
    \label{global_pose_graph}
    \vspace{-2mm}
\end{figure}

\section{Lidar mapping}\label{secLSTMM}
LiDAR mapping uses high frequency IMU rate VIO poses as the motion prior to perform LiDAR points dewarping and scan to map registration. Denote a scan $\chi$ as the point cloud obtained from one complete LiDAR rotation. Geometric features including points on sharp edges and planar surfaces are extracted from $\chi$ before dewarping \cite{refLOAM, refVLOAM}. The registration is then based on feature points from current scan to the map (all previous feature points), solved as an optimization problem by minimizing Euclidean distance residuals formed by the feature points as in \cite{refLOAM}.

\subsection{LiDAR scan dewarping}

Dewarping is required as points from a LiDAR scan are timestamped differently. Denote any time within a scan as $t_{i}$. We dewarp all points to the time of end of scan $t_{k+1}$ based on IMU rate VIO poses. Denote a LiDAR point at $t_i$ as $\textbf{P}_{i}$ and the dewarped itself as $\tilde{\textbf{P}}_i$, we have
\begin{equation}
    \tilde{\textbf{P}}_{i}=(\textbf{T}_{k+1}^L)^{-1}\textbf{T}_{i}^{L}\textbf{P}_{i}
\end{equation}
where $\textbf{T}_{k+1}^{L}$, $\textbf{T}_{i}^{L}$ are LiDAR frame poses transformed from the closest IMU rate VIO poses

\subsection{Scan to map registration}
Feature points from the dewarped scan $\tilde{\chi}$ are registered to the map, optimizing for the LiDAR mapping pose at $t_{k+1}$ denoted as $\textbf{L}_{k+1}$. Denote the initial estimate of $\textbf{L}_{k+1}$ as $\textbf{L}_{k+1}^*$, we have:
\begin{equation}
    \textbf{L}_{k+1}^* = \textbf{L}_k\textbf{T}_{trans}^{L}
\end{equation}
where $\textbf{L}_k$ is the optimized previous LiDAR mapping pose and $\textbf{T}_{trans}^{L}$ is the relative transformation obtained based on IMU rate VIO poses. All dewarped feature points are then transformed to world coordinate system by $\textbf{L}_{k+1}^*$ for registration.

The residual $\textbf{r}_E$ of an edge feature point in the current scan, is the Euclidean distance between itself and the line formed by the two closest edge points in the map. The residual $\textbf{r}_{U}$ of a surface point in the current scan is the distance between itself and the planar patch formed by the three closest surface points in the map. \cite{refLOAM} Incorporating $\textbf{L}_{k+1}^*$, we can rewrite the two residuals as:
\begin{equation}
f_{E}( E_{(c,i)}^{L}, \textbf{L}_{k+1}^*) = \textbf{r}_{E}
\end{equation}
\begin{equation}
f_{U}( U_{(c,i)}^{L}, \textbf{L}_{k+1}^*) = \textbf{r}_{U}
\end{equation}
where $E_{(c,i)}^{L}$ and $U_{(c,i)}^{L}$ are the 3D position of the $i$th dewarped feature point in the LiDAR coordinate system. Levenberg-Marquardt optimizer is used to solve this nonlinear optimization problem, formed by stacking the cost functions for all feature points.

\begin{figure}[!t
\captionsetup[subfloat]{farskip=1pt,captionskip=1pt}
\subfloat[Highbay]{\includegraphics[width=\columnwidth]{traj_map/traj_map_highbay.png}}

\subfloat[Hallway]{\includegraphics[width=\columnwidth]{traj_map/traj_map_hallway.png}}

\subfloat[Tunnel]{\includegraphics[width=\columnwidth]{traj_map/traj_map_tunnel.png}}

\subfloat[Huge Loop]{\includegraphics[width=\columnwidth]{traj_map/traj_map_huge_loop.png}}

\subfloat[Outdoor]{\includegraphics[width=\columnwidth]{traj_map/traj_map_outdoor.png}}

\caption{Trajectories from VIL-SLAM and LOAM are shown on the left and maps generated by VIL-SLAM are shown on the right. Start(end) position is labeled with red triangle in the map and is the origin in the plot.}
\label{traj_map_res}
\vspace{-4mm}
\end{figure}

\section{Lidar enhanced loop closure}\label{secSIELC}
Loop closure is critical to any SLAM system as long term operation introduces drift. The objective of loop closure is to eliminate drift by performing a global pose graph optimization which incorporates loop constraints and relative transformation information from LiDAR mapping. To better assist LiDAR mapping, the corrected LiDAR pose is sent back in real-time so that feature points from new scans are registered to the revisited map. We propose adding ICP alignment in addition to visual Bag-of-Words \cite{refBoW} loop detection and PnP loop constraint formulation. The system uses iSAM2 \cite{refiSAM2}, an incremental solver, to optimize the global pose graph, achieving real-time performance.

\subsection{Loop detection}
Stereo images and LiDAR scans are associated using their timestamps. Let us denote these as key images and key scans respectively. To prevent false loop detection we restrict candidates within a certain time threshold. Loop candidates are detected by testing the key images with the Bag-of-Words \cite{refBoW} database of previous key images. Furthermore, We match feature descriptors of the left key image with the loop candidates to filter out the false positives.

\subsection{Loop constraint}

The system first obtains visual loop constraint as an initial estimate. Since we use a structureless formulation for visual landmarks, triangulation on all the stereo matched features in the loop candidate is performed to obtain their 3D location. Their associations to current key images are given by descriptor match. The visual loop constraint is then evaluated using EPNP \cite{refEPNP}. To improve the accuracy of the visual loop constraint, we use ICP alignment on the feature points of the corresponding LiDAR key scans. With a bad initialization or a larger point count, ICP takes longer to converge and consumes more computation resources. However, the visual loop constraint provides a good initialization point and the ICP only uses sparse feature points (Section \ref{secLSTMM}), which makes it converge faster.

\subsection{Global pose graph optimization}

The graph representation of the global pose graph is shown in Fig. \ref{global_pose_graph}. It contains all the available LiDAR mapping poses as variables, constrained by the \textit{LiDAR Odometry Factor} and the \textit{Loop Constraint Factor}, both are measurements of the relative transformation: $(\textbf{L}_u)^{-1}\textbf{L}_v$ where $u$ and $v$ stand for scan ID and $\textbf{L}_u$, $\textbf{L}_v$ are the associated poses. For the \textit{LiDAR Odometry Factor}, $u$ is the previous scan ID. For the \textit{Loop Constraint Factor}, $u$ is the key scan ID found as loop. For both cases, $v$ is the current scan ID. Poses are expressed in 6 DoF minimum form in the optimization. To realize real-time performance, we use iSAM2 \cite{refiSAM2} to incrementally optimize the global pose graph.

\subsection{Re-localization}
Once a true loop closure candidate is found, LiDAR mapping buffers the feature points (without registering them to the map) until it receives loop correction. The loop correction contains globally optimized trajectory. LiDAR mapping updates its map, adds the buffered feature points to the map and then resumes its operation. We can afford to update the map in real-time because (a) loop closure has a real-time performance (b) the sparse feature map does not take much memory, and (c) scan to map registration is fast enough to catch up the LiDAR data rate.

\begin{table}[!t]
\captionsetup{skip=0pt}
\caption{FDE (\%) and MRE (m) TEST RESULTS\label{FDE}}
\begin{center}
\begin{tabular}{|c|c||c|c||c|c|}
\hline
 \multirow{2}{*}{Test} & Total & \multicolumn{2}{|c||}{FDE} & \multicolumn{2}{|c|}{MRE} \\
 \cline{3-6}
 & Length & VIL-SLAM & LOAM & VIL-SLAM & LOAM \\
\hline
\textit{Highbay} & 118 & \textbf{0.08} & 0.56 & \textbf{0.08} & 0.22 \\
\hline
\textit{Hallway} & 103 & \textbf{0.61} & 0.91 & \textbf{0.10} & 0.27 \\
\hline
\textit{Tunnel} & 85 & \textbf{1.86} & -\tablefootnote{"-" indicates not finished. "$\times$" indicates missing data.} & $\times$ & $\times$ \\
\hline
\textit{Huge} & \multirow{2}{*}{318} & \multirow{2}{*}{\textbf{0.01}} & \multirow{2}{*}{-} &\multirow{2}{*}{\textbf{0.22}} & \multirow{2}{*}{0.36} \\
\textit{Loop} & & & & & \\
\hline
\textit{Outdoor} & 528 & 0.02 & 0.02 & $\times$ & $\times$ \\
\hline
\end{tabular}
\end{center}
\vspace{-4mm}
\end{table}

\section{Experimental results}\label{secER}
We evaluate VIL-SLAM and compare it with the best real-time LiDAR based system, LOAM\footnote{This is the best implementation of LOAM we could find online https://github.com/laboshinl/loam\_velodyne}\cite{refLOAM} on custom datasets. We did not use KITTI odometry dataset \cite{Geiger2012CVPR} because their evaluation sequences do not have inertial measurements which are needed for VIO. Also, most KITTI sequences are not challenging. So they do not evaluate the robustness of these systems which is the main focus of our experiments. We also evaluate the stereo VIO submodule (VIL-VIO) using the EuRoC MAV dataset \cite{refEUROC}.

\begin{figure}[!t]
\captionsetup[subfloat]{farskip=1pt,captionskip=1pt}
\subfloat[Highbay]{\includegraphics[width=\columnwidth]{map_comp/map_comp_highbay2.png}}

\subfloat[Hallway]{\includegraphics[width=\columnwidth]{map_comp/map_comp_hallway.png}}

\subfloat[Huge Loop]{\includegraphics[width=\columnwidth]{map_comp/map_comp_huge_loop.png}}

\caption{Map registration error of VIL-SLAM (right) and LOAM (left) comparing to the model. Errors above 0.3m are colored red for (a-b) and 0.5m for (c). Discontinuous red regions inside the blue and green are due to lack of the model caused by occlusions of the Faro scans.}
\label{map_comp_res}
\vspace{-2mm}
\end{figure}

\subsection{Platform and software}
We built a platform (Fig. \ref{platformFig}(a)) with two megapixel cameras, a 16 scan-line LiDAR, an IMU (400Hz), and a 4GHz computer (with 4 physical cores). We built a custom microcontroller based time synchronization circuit that synchronizes the cameras, LiDAR, IMU and computer by simulating GPS time signals. The software pipeline is implemented in C++ with ROS communication interface. We use GTSAM library \cite{refGTSAM} to build the fixed-lag smoother in the VIO. For loop closure, we use ICP module from  LibPointMatcher \cite{refLibPointMatcher} to align point clouds, DBoW3 \cite{refDBoW3} to build the visual dictionary, and iSAM2 \cite{refiSAM2} implementation in GTSAM \cite{refGTSAM} to conduct global optimization.

\begin{figure}[t!]
    \captionsetup{captionskip=1pt}
    \includegraphics[width=\columnwidth]{loopClosure.png}
    \caption{(a) Map of the tunnel stitched using LIDAR mapping poses. (b) Map of the tunnel stitched using globally refined poses. Double image in (a) is mostly eliminated but not fully, because only one loop constraint is generated, not enough for a full correction. (c) Map of the hallway stitched using LIDAR mapping poses. (d) Map of the hallway stitched using globally refined poses. Double image in (c) is mostly eliminated. Walls are aligned with two loop constraints.}
    \label{lccc}
    \vspace{-2mm}
\end{figure}

\subsection{Tests and results}
We present results from five representative environments including featureless hallways, cluttered highbays, tunnels, and outdoor environments. The data collection started and ended at the same point for all these sequences. Odometry (LiDAR mapping pose) is evaluated based on the final drift error (FDE). Mapping results are evaluated in terms of mean registration error (MRE) using Faro scans as ground truth. We first align the map with the model (Faro scans), and then compute the Euclidean distance between a map point and its closest point in the model \cite{refCC}. The odometry FDE and mapping results are shown in Table \ref{FDE} with the better ones in bold. The trajectories and cross-sectioned maps are shown in Fig. \ref{traj_map_res}. The map comparisons are shown in Fig. \ref{map_comp_res}.

The \textit{highbay} is an indoor warehouse which is open, structured, and rich in features. However, frequent structural occlusions could be a challenge for the visual frontend and the LiDAR feature extraction part. Both VIL-SLAM and LOAM handle this environment pretty well. For VIL-SLAM, LiDAR mapping module registers most of its scan to map, largely reducing the odometry error. Loop closure recognizes the starting position and closes the loop. The map is generated using the globally refined poses, with the majority of map errors below 0.15m.

The \textit{hallway} and \textit{tunnel} tests are challenging environments because of lack of visual features and the degeneracy issue along traversal direction for LiDAR. LOAM accumulates large error in the hallway, and fails the tunnel test mainly due to the degeneracy issue. Aided by the stereo VIO module (VIL-VIO), VIL-SLAM succeeds both tests. In the \textit{hallway} test, the visual frontend returns fewer reliable measurements because of the featureless walls, under-constraining the VIO. This corrupts the map as observed by wall misalignment, which is later corrected by loop closure as shown in Fig. \ref{lccc}(c-d). Loop closure detects the loop twice when approaching the endpoint, lowering FDE to 0.05\% and generating a refined map. In the \textit{tunnel} test, because of the degeneracy issue, VIL-SLAM struggles as well and accumulates some error in the traversal direction. However, loop closure detects the loop at about 3m from the end point, lowering the FDE down to 0.08\% and correcting the map as shown in Fig. \ref{lccc}(a-b).

The \textit{huge loop} test features challenges from both \textit{hallway} and \textit{highbay} environments. In addition, we end the trajectory by re-entering the highbay after traversing along a long narrow corridor. LOAM fails this test after re-entering the highbay, at the place labeled by a red cross in Fig. \ref{traj_map_res}(d). We think this is because it fails to register new scans to the original \textit{highbay} map caused by a large error in z-direction accumulated in the corridor. VIL-SLAM succeeds in this test. Without loop closure being triggered, it achieves 0.01\% FDE in odometry. VIL-SLAM is robust and achieves this result by successfully registering new scans to the original \textit{highbay} map at re-entry. The map generated with the odometry estimate of VIL-SLAM is compared with the map generated with LOAM before its failure. The boxed region is where LOAM accumulates errors leading to its failure.

The \textit{outdoor} test features an outdoor trajectory which is 546m long and includes a gentle slope. Pedestrians and cars were observed which served as potential outliers. VIL-SLAM and LOAM have comparable results along the xy-plane. However, LOAM fails to capture the changes in the z-direction. The inaccuracy in z of LOAM is also observed in the previous tests.

Overall, VIL-SLAM generates more accurate mapping results and lower FDE compare to LOAM when they both finish. Also, VIL-SLAM succeeds the more challenging environments where LOAM fails with qualitatively good mapping and odometry results.

\begin{figure}[t!]
    \centering
    \includegraphics[scale=0.15]{euroc.png}
    \caption{Root mean square error of ATE for EoRoC Dataset.}
    \vspace{-3mm}
    \label{eurocFig}
\end{figure}

\subsection{EuRoC MAV Dataset test}
VIL-VIO contributes to the robustness and accuracy of VIL-SLAM. We evaluate the VIO using the EuRoC MAV dataset \cite{refEUROC} in terms of the absolute trajectory error (ATE) as in \cite{refATE}. Fig. \ref{eurocFig}\footnote{A sequence is named in the first four letters and the difficulty level is encoded in the last letter (E:easy, M:medium, D:difficult)} shows the comparison results between VIL-VIO and three state-of-the-art methods. Results for VIL-VIO are deterministic, obtained in real-time on a desktop with 3.60GHz i7-4790 CPU. Results for the other methods are the better ones from experiments in \cite{Hsiung18iros} and \cite{refRSVIOupenn}. VIL-VIO succeeds all sequences with accuracy comparable with the others, verifying its capability to handle aggressive motion, illumination changes, motion blur and textureless regions.

\section{Conclusions}

VIL-SLAM is a state-of-the-art odometry and mapping system designed to robustly operate long term in different environments. Current framework loosely couples VIL-VIO and LiDAR mapping. We are extending it to a tightly-coupled framework such that refined pose estimate from LiDAR mapping could be used for IMU biases correction. In loop closure, ICP refinement operates on sparse feature points between scans. We suspect that we would obtain a better loop constraint by matching a scan to map.

\addtolength{\textheight}{-12cm}

redpajama_set_name: RedPajamaArXiv


text:
Will Dyson: Australia's Radical Genius
Updated 2016
Will Dyson: Australia's Radical Genius is a superb biography of a brilliant and versatile artist–writer. After finding a niche in his homeland elusive, Dyson became internationally acclaimed as a powerful cartoonist, as an etcher, as Australia's first official war artist, as a writer of prose and verse, and as a scintillating humourist. A stunning overnight success, Dyson was described as the most famous Australian in the world. Absorbing, entertaining and lavishly illustrated, this fascinating biography illuminates the life and times of a remarkable and under-recognised Australian. It was highly commended by the judges of the National Biography Award.
Some of Will Dyson's Drawings
Will Dyson, Australia's first and finest official war artist, created hundreds of drawings of Australia's soldiers at the Western Front
Praise for Will Dyson: Australia's Radical Genius (Scribe, 2006)
Brilliant cartoonist, talented poet, witty conversationalist, passionate nationalist and supporter of the Left: Will Dyson was remarkably gifted. A fiery, outspoken intellectual, as handy with a pair of boxing gloves as he was with a pen, the young Dyson was emblematic of the best Australia had to offer to the world at the beginning of the 20th century. Ross McMullin's stunning biography entertains, educates and entices the reader to ponder what heights our nation might have reached if we had nurtured and hung on to men such as Dyson … The passion and intelligence with which McMullin traces Dyson's career, including his unrivalled work as a war artist with the Australian infantry at the Western Front, allows readers to feel that they have in some way encountered Dyson as an artist and a man. This is what biography should be: not just a pallid regurgitation of the facts of a life, but an engagement with that life.
— Rebecca Edwards, in the Courier–Mail
Will Dyson isn't a household name in Australia, but he should be … Ross McMullin is arguably Australia's most formidable historian, and his book Will Dyson: Australia's Radical Genius [is] an outstanding work … a first-class biography of an extraordinary Australian … McMullin's biography cements Dyson's reputation … truly inspiring reading.
— Stephen Loosley, in the Sunday Telegraph
Will Dyson was a brilliant and creative individual who early in the 20th century produced some of the most memorable caricatures to be published in Australia and Britain … Dyson was a firebrand in Australian left-wing radical politics, provocative, genuinely funny, endlessly entertaining and committed to his idea of Australia. He internationalised Australian humour and made his soapbox into a world stage … The work here is brilliant, memorable and stands up well to international comparisons. However, unlike many other artists who travelled abroad, Dyson never forgot that he was an Australian and was proud of his working-class background.
— Professor Sasha Griffin, in the Canberra Times
Will Dyson was a talented artist, a great thinker and orator, a gifted wordsmith and poet and a deeply political being. His satire was biting, his wit was sharp and his work was inseparable from his identity. Ross McMullin has drawn a nuanced and thorough portrait … Will Dyson: Australia's Radical Genius is a biography, a political history, a World War I history and a partial history of Australian art and literature … The many examples of Dyson's work are also fascinating.
— Cathy Wilcox, in Labour History
Will Dyson the irrepressible humorist with his daughter Betty after their return to Melbourne in 1925.
Dyson is certainly an important, often unregarded, figure in the history of political cartooning. The story of this talented, likeable, thoroughly political man is well worth knowing on many fronts: as a saga of early Melbourne working-class bohemian culture, as an example of the invigorating effect on English political cartooning by antipodean artists in the early part of the twentieth century … and as an account of the way that World War I registered on a sensitive, and responsible, Australian imagination … A fractured Dyson eventually returned to Australia in the company of his precocious daughter, Betty … This new edition prints an extraordinary photograph of her, proud and gorgeous, hands on hips, pressing her shoe firmly into the ear of her prostrate father's adoring, ground-scraping head … It is good to have this absorbing book, from which all the details above derive, back in print. McMullin is especially rewarding to read on the social and wartime background to Dyson's life.
— Dr Iain Topliss, in Australian Book Review
Will Dyson: Australia's Radical Genius remains a very impressive book. It not only brings to life a remarkably talented individual (Dyson was also a poet of ability, and experimented with his own animation system), it also recreates the era from which he emerged. Jimi Hendrix famously called the blues 'the reflection of the world'. McMullin shows that biography, at its best, can be something similar.
— Dr Jeff Sparrow, in Overland
The book is handsomely produced with cartoons and sketches often given generous full-page treatment … It also contains an excellent range of photographs of family (both the Dysons and the Lindsays), friends, the front, and Dyson's passage through life. Above all, however, are the images of Ruby, especially the delicate refinement and serene beauty of the portrait [that] reminds one of the young Ingrid Bergman.
— Dr Bernard Whimpress, in API Review of Books
The strength of this book lies in McMullin's ability to weave together the story of Dyson's personal, intellectual and professional lives … With this superb biography, McMullin … has resurrected a great Australian and put him back on the pedestal where he belongs.
— David Cooney, in The Weekly Times
Decades earlier, in 1984, a different version of the book had been published with the title Will Dyson: Cartoonist, Etcher and Australia's Finest War Artist. Here are some assessments:
Ross McMullin's biography of Will Dyson is being widely welcomed … McMullin has responded equally to Dyson's achievement as cartoonist and artist, and to his ebullient, intelligent and continually interesting personality. Neither the meticulous detail of research nor the careful presentation of contemporary background events diminish the vitality of the subject. In this, surely, lies McMullin's success as biographer … Dyson's commitments to causes, his campaigns against injustice, his concern, his wit, his sociability — all these made him very responsive to external events. His biography can therefore be read as a commentary on such matters as conscription, developing nationality, women's suffrage, Australia's part in World War I, the dilemmas of the expatriate artist of talent, the growth of radicalism, the Douglas Credit system — and much more.
— Rosemary Dobson, in the Age
The world had to wait a long time for a proper presentation of Will Dyson, in word and drawings, but when it came, the work was done perfectly — in Ross McMullin's … book on one of the three greatest cartoonists of the century … a beautifully produced, illustrated and constructed volume … Once the full story is unravelled with Ross McMullin's skill and sympathy, his real greatness is enhanced … All the more remarkable was Will Dyson's achievement [before 1914] in producing the cartoons which embody best the spirit of the age … Here enshrined indelibly is what the Suffragette fight felt like, what freshly confident trades unionism felt like … Many of the cartoons from this period can still make us catch our breath, by their poignancy, by their ferocity.
— Michael Foot, journalist, biographer and leader of the British Labour Party 1980-1983, in his book Loyalists and Loners (1986)
In so many ways Ross McMullin's book is a splendid biography … a thorough piece of research, written in a manner which ensures its accessibility to the wider public. It not only throws new light on Dyson, but also provides a vast amount of information on Melbourne and Sydney's art, literary and publishing figures … Why Australia failed to keep Dyson when he returned in 1925 is suggested in the book through an elaborate and fascinating account of our attitudes and social climate at that time.
— Professor Doug Hall, director of the Queensland Art Gallery 1987-2007, in Overland
Will Dyson, the subject of Ross McMullin's important biography, … became the most famous and admonishing satirist Australia had produced. In his irony and force he has not been approached as a cartoonist by any Australian then or since … Ross McMullin's book … is the first major, and welcome, work about this remarkable Australian. The chapter titled 'The Great War' is particularly fine.
— Vane Lindesay, in Australian Book Review


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