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The Velka Pardubicka 2019
All things Velka Pardubicka 2019
In around 6 hours time I fly to Prague to take in this year's big race. I've been to Prague a few times before but never for the racing. I'm going with a few friends, including Martin (@quevega – for those of you on twitter), who's kindly written the following article.
There's a bit of history, a look at some of the runners and riders and even some tourist advice if you're making the trip! 🙂
I hope you enjoy reading through this as much as I did. I'll try and 'tweet' a bit through the weekend from the track, signal allowing, @Josh_HW – and you can follow those either on twitter or use my twitter feed to the right hand side of this blog (when on desktop/tablet)
Over to Martin…
First held in 1874 the Velka Pardubicka is arguably continental Europe's most famous steeplechase. Incorporating various hedges, water jumps, banks, doubles and the famous Taxis which comes up as the fourth fence in the race.
There has been plenty of British and Irish success over the years and with the race and course based loosely on that of Aintree's Grand National course the late 1800's and early 1900's, renewals were popular with riders from this side of the channel.
In the post-war era however the race has been dominated by local riders with only Christopher Collins, who partnered Stephen's Society to victory in 1973 and current Rules trainer Charlie Mann who rode It's A Snip when he triumphed in 1995, have provided Britain or Ireland with a victory in the past 50 years.
With regards this year's renewal… after a run of little interest horse wise from UK trainers the David Pipe-trained Rathlin Rose, a winner at Ascot earlier in the year, is set to represent the UK with James Best taking the ride.
There will be further British and Irish interests in the race with Andrew Glassonbury partnering Ribelino, the winner via disqualification of this race back in 2015 while Tom Garner is set to ride last years third Stretton and Leighton Aspell the injury prone Talent, who won the final qualification race for this contest last month on his first start in well over 12 months.
Josef Vana is perhaps the most famous name associated with the race having ridden the winner of the race on no fewer than eight occasions, including four times on the great Zeleznik in the late 80's and early 90's.
Now a trainer, Vana will be well represented in races over the two days and holds strong claims in the main race itself through Theophilos, Ange Guardian, Mazhilis and Zarif with the second named the winner of two qualifying races in 2019.
Last years winner Tzigane Du Berlais heads the market with the local firms for this year's renewal and he has run decent races on both starts this campaign finishing runner-up to Ange Guardian in the first qualifier in May and fifth to Talent last month. While on the face of it some will have been disappointed with last months performance it's worth noting he has been targeted at this race since last October and with regular jockey Jan Faltejsek, who used to ride in the UK for George Charlton, in the saddle he has the services of a top jockey.
Chief market rivals are two of the Vana pair in Theophilos and Ange Guardian but both of those have stamina concerns with the former yet to race over further than 5800m – he finished runner-up over here last month – and the latter having managed a best effort of second in 2016 from three attempts at this race (he also finished fifth in 2017 and sixth last year). Expect to see Ange Guardian in the green and yellow colours with the big white face racing towards the rear in the early stages.
Talent has arguably been unlucky in his career so far in that it has been beset by injury with the gelding having had just three starts since winning a 5000m Grade 3 cross-country event at Merano in June 2017. He has however proven himself to be a classy performer for trainer Hana Kabelkova and he impressed in winning the fourth qualification race here last month.
Like many Czech horses these days Mazhilis has made many a trip to Italy in recent years with the gelding notching up five victories at Merano including in a 5000m Grade 1 chase in June 2016. The Josef Vana-trained Country Reel gelding has placed in Grade 1 company since and while he has been beaten in lowly category four races at Pardubice this season he put in a good performance when third in the qualifier here last month and is a notable runner upped in trip with Jan Kratochvil who took this race two years ago set to ride.
Player was put up as the nap of the meeting in 2017 with my comment being " if there's a future Velka horse in the race restricted to five-year-old's then he is it." And while Mahony also lines up from that five-year-old only contest preference would be for Player who was paced in the first qualifier here in the spring. Player sprung something of a surprise when dropping in grade to defeat last years Velka second Hegnus here last month and while he is likely to hit flat spots once more he looks likely to appreciate this step up in trip.
Delight My Fire finished third in this race two years ago but hasn't looked the same horse since, failing to finish here 12 months ago and recording her most recent victory in a category one 5200m cross-country race at Slusovice last November.
The dark horse in the field is undoubtedly Beau Rochelais who was purchased by owners DS Pegas, who also had multiple winner Orphee Des Blins for trainer Cestmir Olehla, after the gelding qualified for this race with a second place finish in a cross-country contest at Le Touquet just over a month ago.
Of those at bigger prices I always thought that Dulcar De Sivola had shown enough in his chase victory in France at Nantes in October 2017 to make up into a useful cross-country horse in the Czech Republic but sadly he's not really got his act together since finishing runner-up in a category three 4400m race on his first Czech start in May 2018.
The Undercard
On the undercard of Sunday's race, the Cena Labe is the feature, generally a race that sees some of the best young cross-country horses go up against one another with it being referred to as a "novices Velka" in some quarters. It's far from being as great a test as the big race itself but looking at the local markets it plays host to the best bet, the NAP if you will of the day with the eight-year-old Lombargini and Jan Faltejsek looking capable of taking what should effectively be a match with Marcus Aurelius following a good third place finish here in August.
There has been plenty of talk about restrictions on gambling in the Czech Republic in recent years with punters no longer able to just walk into a Fortuna betting shop on the Prague high street, or more popularly a metro station, and being able to place a bet so visitors have been restricted to betting with the on course firm Betino, who's margin is something that Dick Turpin might have aspired to had he run a book on racing.
There are still some doubts about whether punters will be able to bet with Betino without registering and I have been getting mixed messages in this regard but I'm hopeful that there will be no issues, particularly with it being the biggest race meeting of the year and all eyes on Pardubice.
For anyone who hasn't been I can recommend the first day of the meeting as a brilliant day out with competitive racing and a wide range of beers and local food to sample. It's also a great day for attending if keen to get your bearings with regards to the stands, the track itself, parade ring, toilets etc.
The first race on the Saturday is due off at 12:00 with the opener being an amateur riders Flat race which should go to Epauled and Jindrich Fabris, followed by a pony race which I'm no expert on and there'll be no betting on but would expect Kessy to run well despite being the second smallest pony in the field.
The rest of the Saturday card is made up of handicap chases over a regulation course, but newcomers will find it hard to tell the difference between those races and the cross-country events and also hurdles with British riders Sam Lee, David Prichard and Nathan Rahman lining up alongside Swede Elliot Ohgren, American Mark Galligan plus Tereza Polesna, Marcel Altenburger, Frenchman Gonzague Cottreau and also Kim Stern in a Fegentri riders hurdle race.
Ohgren's mount Gontchar won the Czech Derby at Velka Chuchle (Prague) back in 2016 but missed the whole of 2017 and was a beaten odds-on favourite when making his hurdling debut last month.
The first race, a category two cross-country chase is due off at 11:30am with the main race the last one on the card at 16:40, though due to the procedures and parades etc. it's invariably a good 10 or 15 minutes late off.
Expect a dash for the trains back to Prague afterwards so it's likely to be standing room only on most but there'll be a good atmosphere at the track and plenty of people in attendance.
Anyone interested in taking in true Czech sporting culture should try and get to a game of ice hockey with the main team in Prague, Sparta, playing at home on Tuesday evening against HC Verva Litvinov at the O2 Arena (Ceskomoravska on Line B of the metro) which is very easy to get to from all parts of Prague.
I can also recommend a trip to Saints Cyril and the Methodius Cathedral which has the story of Operation Anthropoid, which is well worth reading up on, and also the Museum Of Communism is a great place to visit in the middle of the city.
I usually stay near Andel and there are plenty of good restaurants there, in particular Kobe Fusion restaurant does some great dishes, and for those after something more familiar there's plenty of pizza and pasta places plus a TGI Friday's, McDonalds and a KFC in the area.
I hope anyone heading out for the big meeting enjoys the two days and if you see me do say hello (probably be wearing a brown/orange jacket)
My thanks to Martin for that. I probably owe him a few beers now.
Happy Punting,
ps. here's the course >>>
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Ayyappa temple opens, 10 women sent back by police
in Culture, INDIA, PTI
by Youth Darpan November 17, 2019, 12:40 am 2.6k Views
Amid tight security, thousands of devotees offered prayers at the Lord Ayyappa temple when it opened for the annual Mandala-Makaravilakku puja on Saturday, though police said 10 women were sent back from Pamba base as they were in the "barred" age group.
The temple has reopened just days after a five-judge bench of the Supreme Court referred to a larger bench the matter related to entry of women into the hill temple and other issues related to various faiths.
The state and temple precincts had witnessed protests by right wing outfits and BJP workers last year after the LDF government had decided to implement the Supreme Court verdict of September 28, 2018 allowing women of all age groups to offer prayers at the shrine.
Though the apex court did not stay its earlier order allowing entry of women in the Lord Ayyappa temple, the LDF government in Kerala this time said the shrine is not a ground for activism and made it clear that it would not encourage women who want to visit the temple for publicity.
Police on Saturday evening said at least 10 women, who were part of a 30-member group from Vijayawada in Andhra Pradesh, were sent back from Pamba, five km from the shrine, as they were found to be in the age group of 10-50 years. Females in this age group have traditionally been barred from praying at the temple
"We checked their identity cards and found that they were in the barred age group and informed them about the current situation in Sabarimala. They did not proceed further," a police official said.
Early this year, two women in the barred age group– Bindhu and Kanakadurga–had trekked the holy hills and offered prayers at the shrine, scripting history on January 2.
However, Devaswom Minister Kadakampally Surendran has said those who want to visit the temple can procure a court order to enter the temple.
At five pm on Saturday, Kandararu Mahesh Mohanararu opened the sanctum sanctorum of the temple, located in a reserve forest of the Western Ghats in Pathanamthitta district of the state, and performed the pooja.
The devotees from Kerala, Tamil Nadu, and other neighbouring states, who were allowed to trek the hill from 2 pm, climbed the sacred 18 steps to the temple with the "irumudikettu" (sacred bag containing the offerings to the Lord) after the priests performed the "padipooja".
While A K Sudheer Namboodiri took charge as Sabarimala melshanti (chief priest), MS Parameswaran Namboodiri who was to take charge as priest of the Malikappuram Devi Temple could not do so following a death in his family.
He is likely to take charge by November 23, according to officials.
The Devaswom board, which manages the temples in the state, has made elaborate arrangements to provide maximum amenities to the devotees.
The unprecedented floods during August last year had played havoc with the pilgrimage season with most of the facilities for the devotees being destroyed.
Resting places for the devotees at Nilackal, Pamba and Sannidhanam have already been set up along with medical, water and toilet facilities.
Some devotees claimed that due to the rush they had difficulty finding eateries, but officials said that there were enough hotels at Sannidhanam to cater to them.
"There are enough eateries for devotees but it was drizzling. The annadanam (offering food for the devotees) by authorities will start only from tomorrow, ie the first day of Malayalam month "Vrischikam"," a senior government official stationed at Sannidhanam told PTI.
A police official stationed at Pamba said 13,500 devotees had visited the place till 11.30 pm.
The route for trekking to the hill was opened at 2 pm and the sanctum sanctorum was closed for the day at 9.50 pm after the devotional song "Harivarasanam". It will reopen at 3 am.
Over 10,000 police personnel would be posted in phases in and around the Lord Ayyappa temple for security purposes during the pilgrimage season.
The temple, which is located deep inside the Periyar Tiger Reserve, is opened for worship only during the days of Mandalapooja, Makaravilakku and Vishu festivals.
It is also opened during the first five days of every Malayalam month.
During this pilgrimage season, the temple will be open till December 27 for the Mandalapooja after which it will be closed for three days.
The shrine will reopen on December 30 for the Makaravilakku festival after which it will close on January 20.
A five-judge bench headed by Chief Justice of India Ranjan Gogoi on Thursday said a larger bench will re-examine various religious issues, including the entry of women into the hill temple and mosques and the practice of female genital mutilation in the Dawoodi Bohra community.
By a 3:2 verdict, it decided to keep pending the pleas seeking a review of its decision regarding the entry of women into the shrine, and said restrictions on women in religious places was not restricted to Sabarimala alone and was prevalent in other religions as well.
The temple, dedicated to Lord Ayyappa, is situated on a hilltop about 4,000 ft above sea level.
Meanwhile, Renaissance Protection committee, an LDF initiative, lashed out at the Left government, saying it had gone "soft" on its stand on women entry issue and this will only help "weaken" the cause.
(With the Inputs of PTI).
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redpajama_set_name: RedPajamaCommonCrawl


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Rendez-moi justice (titre original: Alibi) est un film allemand réalisé par Alfred Weidenmann, sorti en 1955.

Synopsis
Comme reporter en chef de l'Express, Peter Hansen rend compte des événements dans le monde. Il couvre actuellement les essais nucléaires américains. Roland, reporter local, est en pleine tourmente. L'épouse du célèbre scientifique Dr. Overbeck a été assassinée. Roland a assisté à l'arrestation du meurtrier présumé. Mais Hansen, qui n'a pas d'intérêt pour les faits divers, couvre l'affaire en dix lignes puis repart en reportage.

Hansen revient à Hambourg après quelques mois. Il trouve dans sa boîte aux lettres une convocation pour être juré dans le procès pour assassinat du Dr. Overbeck. L'accusé s'appelle Harald Meinhardt. Le jeune homme était l'amant de la riche épouse. Réfugié et orphelin, il pensait qu'elle était l'amour de sa vie. Le mari a appris la liaison. Après une confrontation avec Meinhardt et une réunion des trois personnes,  Overbeck est retrouvée assassinée. Les éléments contre Meinhardt semblent incontestables. Bien qu'il nie le meurtre, il est condamné à dix ans de maison de correction.

Hansen, qui entre-temps s'est remis en question sur son métier de journaliste, est le seul juré à ne pas avoir voté pour la condamnation. Il croit en l'innocence de Meinhardt et commence à mener sa propre enquête. Quand il veut la publier, il entre en conflit avec son éditeur. Mais quand Hansen trouve des preuves supplémentaires, il peut commencer une campagne de presse dans l'Express, menant à la découvert du véritable meurtrier : Overbeck. Harald Meinhardt est libéré.

Fiche technique
 Titre : Rendez-moi justice
 Titre original : Alibi
 Réalisation : Alfred Weidenmann, assisté de Wieland Liebske
 Scénario : Herbert Reinecker
 Musique : Hans-Martin Majewski
 Direction artistique : Rolf Zehetbauer
 Photographie : Helmuth Ashley
 Son : Hans Löhmer
 Montage : Carl Otto Bartning
 Production :
 Sociétés de production : Fama-Film
 Société de distribution : Europa-Filmverleih AG
 Pays d'origine :
 Langue : allemand
 Format : Noir et blanc - 1,37:1 - Mono - 35 mm
 Genre : Policier
 Durée : 103 minutes
 Dates de sortie :
  : .
  : .
  : .
  : .
  : .

Distribution
 O. E. Hasse : Peter Hansen
 Martin Held : Dr. Overbeck
 Hardy Krüger : Harald Meinhardt
 Eva-Ingeborg Scholz : Inge Römer
 Gisela von Collande :
 Charles Brauer : Walter Hansen, le fils
 Almut Rothweiler :  Overbeck
 Walter Werner : Le père de Harald Meinhardt
 Peer Schmidt : Roland
 Ernst Waldow : Le commissaire Lukkas
 Jan Hendriks : Berthold
 Helga Roloff : Dr. Klausen
 Franz-Otto Krüger : Vilessen
 Siegfried Schürenberg : Le président de la Cour
 Franz Essel : Le procureur général
 Hermann Holve : L'avoact des parties civiles
 Hans-Albert Martens : L'avocat de la défense
 Helmuth Rudolph : von Pleskau, le rédacteur en chef
 Charles Regnier : Dietmar
 Ludwig Linkmann : Becker, le rédacteur local
 Claus Götze-Claren : Un journaliste
 Heinz Giese : Un journaliste
 Alexander Welbat : Un journaliste
 Maria Sebaldt : La journaliste de mode
 Maly Delschaft :  Wilke
 Alexa von Porembsky : Maria, la femme de ménage
 Stanislav Ledinek : Brockmann, le patron de bar
 Arno Paulsen : Le chauffeur de taxi
 Walter Tarrach : Dr. Fischer
 Alfred Maack : Beermann, commerçant
 Kurt Weitkamp : Wichmann, commissaire criminel
 Alexander Hunzinger : Le crieur
 Hans Henningsen : Un marin
 Fany Spornitz : Dr. Brandt
 Friedrich Maurer : Lieske
 Valentin Klaus : Dahl, agriculteur
 Wilfried Fraß : Stolle, carreleur
 Walter Bluhm : L'officier de justice
 Hans Hessling : L'invité du bar

Notes et références

Source de traduction

Liens externes

Film réalisé par Alfred Weidenmann
Film allemand sorti en 1955
Film policier allemand
Film allemand sur la justice
Film allemand en noir et blanc
Film de procès
Film avec une musique composée par Hans-Martin Majewski

redpajama_set_name: RedPajamaWikipedia


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Panya Clark Espinal: Vagabond Vitrine
Sunday, June 27 , 2010 - Thursday, August 05 , 2010
Vagabond Vitrine
by Shannon Anderson
By some strange serendipity, the installation of Panya Clark Espinal's Vagabond Vitrine has coincided with a rare period of upheaval in Toronto. The G20 Summit, which has brought together the world's political leaders under the city's roof this year, wraps up on the same day as this exhibition's opening. So, while Clark Espinal pieces together her installation on College Street's busy sidewalk, thousands of security personnel prepare the streets for violent protests, leaving the public to renegotiate their place within what amounts to a temporary police state. Today is Friday, two days before the opening reception – the piece is still unfinished, airplanes carrying Presidents and Prime Ministers are touching down at Pearson – but given the themes of transition and uncertainty inherent in Vagabond Vitrine, I can think of no better climate for writing about the piece.
This is not the Toronto that we know and recognize, this is something new, and our levels of relative comfort take a dip as we anticipate the unknown. It didn't help that the earth literally shook at our feet on Wednesday when the city felt its first earthquake, however minor in this region, in more than a decade. Both events serve as reminders that the stability of our corner of the world is a fortunate, but not certain, state of existence. Anything could shift at any moment. This week provides a small taste of what other cities experience daily.
Panya Clark Espinal, Vagabond Vitrine (installation detail), 2010. Photo: Isaac Applebaum.
Thus far, I've only seen Vagabond Vitrine in the process of becoming: sections of an oak and glass vitrine (rescued from the old Koffler Gallery prior to its demolition to make way for the new Koffler Centre of the Arts), a cardboard scale model, loose piles of birch branches and faux green leaves, and two cowbirds with a small nest carefully packed inside a box. What one might construe as a privileged view of a work-in-progress is nothing of the sort – Clark Espinal has worked on the street all week, in full public view, as Vagabond Vitrine comes together. Men (because, as the artist tells me, it has invariably been males) tend to stare, curious and confused, at the vitrine lying partway outside the store window, and comment, "I don't think it's going to fit." Here, the border between the public and the art will never entrench itself as Clark Espinal's structure spills out onto the sidewalk, shifting and interrupting the residents' familiar streetscape.
For the hottest month of the summer, this sculpture will reside on College Street, partially nestled into its new environs, half-exposed and half-protected by a store window, its multiple panes of glass and wood by turn revealing and obscuring their contents. As with any public art accessible 24/7, Vagabond Vitrine is at the mercy of graffiti artists and looting bar-hoppers (and, this week at least, violent protestors). But, save for the possibility of complete destruction, Clark Espinal takes the risk in stride, not only accepting the possibility that damage may come its way, but even welcoming a roosting pigeon or graffiti tag, as her sculpture integrates this new, if temporary, urban habitat. The vitrine's contents – nature mural, branches, birds and nest – suggest a collision between the natural and urban world, or more specifically, a collision between the museum and the street. Even situated within this eclectic corner of the city (this particular city block houses everything from a tattoo parlour to a Lutheran church) the pseudo-natural-history-museum display is out of place, as though a strange time warp has opened up. Then again, museum displays are time warps, distilled tableaux of imagined environments, slivers of utopian natural wonder.
Displays of this sort tend to showcase rare and elaborate species, so the presence of common cowbirds might seem an odd choice. But just as the vitrine has shimmied its way into another display window, cowbirds have the unusual habit of laying their eggs in the nests of other bird species. Nomadic by nature, they are vagabonds in their own right, with a rearing technique achieved through adaptation to aid their survival. Vagabond Vitrine freezes the moment after the cowbirds have struck again, laying one of their eggs in the nest of another. In the urban world, such adaptive trickery is an essential component of nature's survival. These themes of survival and invasion hold a peculiar resonance at this moment, when what might otherwise be a peaceful summer in the city is fraught with turbulence.
What remains at the end of this strange week? When the piece opens on Sunday, it will coincide with the end of the Summit, and likely the end of Toronto's temporary drama. Vagabond Vitrine is one remainder, clutching to the side of a storefront window, and right now it's difficult not to associate the fractured, inside/outside, push and pull of its structure with the week's unorthodox events. Will those who stumble across this curious sculpture over the coming month be reminded of the day the earth rumbled and they weren't sure if it was an earthquake or a military helicopter? And afterwards, when Vagabond Vitrine dislodges, will it search for a new home? Given the uncertainty of the current moment, that seems like a long ways away.
Panya Clark Espinal, Vagabond Vitrine (installation detail), 2010.Photo: Isaac Applebaum.
It's the day after the opening, a quiet Monday morning, and from a perch across the street I watch people passing Vagabond Vitrine. Many pause at the presence of a small nest tucked into the sculpture's outer corner, but the vitrine is surprisingly innocuous, already at home in the mashup of storefronts. For those who pause longer and peer through the fractured panes of glass, the sculpture's other contents are soon revealed. In the aftermath of the protests that took over the streets just a few blocks away – leaving windows shattered and police cars burning – Vagabond Vitrine seems a little like something abandoned in the midst of the chaos, despite the fact that this neighbourhood seems relatively untouched. Something is clearly disjointed, but for the moment, anything out of the ordinary is still standard fare.
The artist would like to thank: Rochelle Rubinstein, Georgia Guenther, Mark Peck, Brian Davis, Jennifer Sciarrino, Maggie Flynn, Mark Visperas, Andrew Kilpatrick, Nathanael Gray, David Cathro, Crystal Mowry, Jamie Crane, Paul Fulton, Jim Ruxton, Javier Espinal.
Panya Clark Espinal was awarded the Governor General's Medal upon graduating from the Ontario College of Art in 1988. Her practice as a multi-media installation artist has scrutinized and engaged the mechanisms that drive the making of meaning in our culture. She has shown across Canada and in several international cities including Tokyo and London. Key solo exhibitions include Oakville Galleries (2001); the Canadian Embassy, Tokyo (1999); the National Gallery of Canada (1995); Art Gallery of Ontario (1994); and the Southern Alberta Art Gallery (1994). More recently Clark Espinal co-led a collaborative project for the Harbourfront Centre entitled The Terrarium Project. In addition, she has completed a number of public art commissions including Toronto's Bayview Subway Station and is currently working on projects for the City of Mississauga, the Toronto Transit Commission and North Toronto Collegiate Institute. Clark Espinal is represented by Christopher Cutts Gallery in Toronto.
Shannon Anderson is an independent writer, curator and freelance editor based in Oakville, Ontario. Her writing has appeared in publications produced by the Art Gallery of Southwestern Manitoba, Oakville Galleries, Musee d'art de Joliette, the Thames Art Gallery, YYZ Artists' Outlet, and various art magazines, including Azure, Art Papers, and Canadian Art.
Design and editing: Tony Hewer | Photography: Isaac Applebaum
Digital publication to the exhibition Panya Clark Espinal: Vagabond Vitrine
Presented by the Koffler Gallery Off-Site at Mon Ton Window Gallery, 402 College Street | June 27 to August 5, 2010
Curator: Mona Filip
© Koffler Centre of the Arts, 2010, in collaboration with the individual contributors. All rights reserved.
ISBN 978-0-920863-90-9.


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"You have the right to remain private. Anything you post can and will be used against you." So states a new infographic from TrendLabs that takes a look at the risks of posting too much personal information in social networks.
"You have the right to remain private. Anything you post can and will be used against you." So states a new infographic from TrendLabs that takes a look at the risks of posting too much personal information in social networks.
Popular social networks like Facebook, Twitter, Pinterest and Google+ let you post all sorts of personal information, from your location (i.e. where you are right at this moment) to who all your friends are, your full name, your personal email and phone number, your birthday, your photographs, your links across the web and more.
Many of us post and share this information without batting an eyelash. The infographic, 'The Risks of Posting in Social Networks,' illustrates why we should think twice before sharing "TMI" on the web.
The risks of making too much of your information publicly available include damaging your reputation, cyber bullying, falling prey to social engineering schemes, identity theft, targeted advertising and real-world threats like burglary and stalking.
Check out the full infographic below and feel free to share your thoughts with us in the comments. Are you careful about what you post in social networks?


D@mn girl, you are stubborn!
Every day when I walk out the door to do my run…..I have this knot in my stomach. It's a worry — a worry that today will be the day that I can't run. That today is the day the big charade is over……and my true weak, non-Runner identity will be exposed to the whole world. Everyday.
Everyday? Really? D@mn girl, you are stubborn.
Have you not learned anything bout yourself in all these weeks? All the improvements in your breathing, your energy, your speed, pace, endurance. All the strength that you have built — have you not been able to feel it, see it, sense it, KNOW IT? What has to happen Diane, for you to Believe in Yourself? What more do you need? Don't you remember how back in September, the mere sight of those weeks with the 6 mile runs just gave you a nauseous stomach? Don't you remember? And what happens now? Cuz N.O.W. is those weeks. You go out. You run those 6 mile runs. You F.I.G.H.T for them. You F.I.N.I.S.H. them. Every day. Wednesday. Thursday, Friday. And even some Saturdays. Are they all flukes, Diane? D@mn girl, you are stubborn!
There is no big charade! This has not been a fluke! You. Y.O.U. have done the work. Y.O.U have been determined. Y.O.U. have earned every single one of those miles. They didn't just happen. And sure as hell, nobody gifted them to you. Y.O.U. claimed them, banged them out, served them up, and ate them for breakfast. For months. and months. D@mn girl, you are stubborn!
You've been lying to yourself. You've been whispering to yourself that it's getting too hard. Been telling yourself that it's getting scary.
You have been getting ready…all along….just for this. For these long runs. For the 18 miles. For the 20 miles. For the 22 miles. For the ultimate…26.2 miles. THIS is what it has been all about, all along! Y.O.U. are ready. Y.O.U. are strong enough. Y.O.U. are not scared. Y.O.U. are going to LOVE this.
Y.O.U are about to experience one of the highlights of your life. Don't you get it? Let that Idea settle in on you.
Start Seeing It For What It Is.
Y.O.U. have worked for this.
No one gave it to Y.O.U.
and when you are out there. Doing the 20 on Sunday. Girl, Be D@MN STUBBORN! Be STUBBORN THAT day. Because you are ready. Y.O.U. KNOW HOW! Now, Go Do IT!


BioShock Infinite is a sublime shooter set in a magical world. While the campaign's final third never quite lives up to its breathtaking opening, there's more than enough intrigue imprisoned within Columbia's curious suspended districts to keep you compelled from the beginning right through to the very end.
BioShock Infinite didn't have the same impact on me as the original BioShock. That is, perhaps, to be expected for a sequel--especially a sequel that stands nearly completely on its own. However, BioShock Infinite is one of the only truly complete gaming experiences. It hits every beat just right and left me actually caring about the characters, intrigued by the mysterious city, and perplexed by the convoluted story.
While the end of 2013 will be filled with talk about a new generation of video games, BioShock Infinite's narrative will stand out as an achievement, helping put a cap on a generation that propelled narrative as a focus for the industry. Undoubtedly the finest game crafted by Irrational Games, BioShock Infinite is one of the best told stories of this generation. It simply cannot be missed.
BioShock Infinite is a game that has received a lot of hype. With our review publishing after the majority of other reviews had already given it a perfect score, I went into the game looking for the negatives. I wanted to find something wrong, some annoyance, or anything to not buy into the hype. Truth be told, the negatives are not to be found, or if they are, they are so minor that they do not at all mar the finish of the rest of the game.
BioShock Infinite could make you feel uncomfortable. If you adhere to religious faith, or celebrate American idealism, this game may invite introspection or even anger. BioShock Infinite isn't afraid to magnify the way religious and racial extremism inform our culture and change lives. It isn't afraid to depict a less-than-holy trinity diseased by power, deception, and manipulation.
Infinite is more than a new setting, story, and characters; those elements are seamlessly integrated with complex themes, a mysterious plot, and entertaining combat to create an amazing experience from beginning to end. Familiar threads run through it – a lighthouse, a strange city, a charismatic antagonist – but they are homages to the past rather than attempts to recycle it.
At the end of the day, Ken Levine and the crew at Irrational Games have crafted an amazing journey through a fantastic city with two of the most compelling characters gaming has seen in a long while. We've waited for what seems like forever, but now that Infinite's finally flying across the gaming stratosphere, we're free to come along for the ride. Columbia may not really be heaven, but it's the closest we've come in a while.
In total, BioShock Infinite is a brilliant shooter that nudges the entire genre forward with innovations in both storytelling and gameplay. It trips over itself in a couple of spots, but not in any way that should keep you from embracing it with your utmost enthusiasm.
All in all, Infinite's story plays its cards very well throughout and there's a few clever surprises along the way. The backstory of Columbia is also fleshed out by Voxophones – audio recordings which you can find with a little bit of exploring – these are extremely interesting and tie everything together without the need of it getting in the way of the plot at hand.
The graphics are wonderful, the atmosphere great, soundtrack superb. The action is amazing, the story affecting. I've tried damn hard, but I couldn't find anything to dismiss during my time twice-through with the game. Irrational Games have created a masterpiece.
BioShock Infinite sólo tiene un problema: que tiene que luchar contra sí mismo. Mientras jugamos, resulta inevitable compararlo con el original. Y el primer BioShock es uno de los grandes de esta generación... ¿Aguanta Infinite esta comparación? En nuestra opinión, sí. Es cierto que no sorprende tanto como aquél, pero está todo tan cuidado y tan bien diseñado y sus combates son tan divertidos gracias a sus múltiples opciones que es imposible resistirse a descubrir los misterios que encierra.
Un fantástico e imaginativo juego de acción que recoge a la perfección el legado de Bioshock y logra mejorarlo en diversos apartados. La recreación de la ciudad de Columbia es absolutamente magistral, una enorme combinación entre visión, tecnología y talento artístico que nos permite explorar uno de los mejores entornos virtuales de esta generación. La acción es intensa, variada y nunca llega a cansar, puede que sea algo más reminiscente de la de Bioshock de lo que hubiera sido deseable, pero también funciona mejor.
Cuando Ken Levine habla, la industria del videojuego escucha. El prestigioso creativo ha querido centrarse en esta ocasión en la historia, y el resultado logrado ha sido asombroso. Sin descuidar la perspectiva jugable, el nuevo Bioshock se erige como uno de los grandes shooters de los últimos años. Infinite logra, con estos puntales, ser uno de esos escasos lanzamientos que cada temporada logran ser imprescindibles.
Nein, BioShock braucht die eine überraschende Wendung nicht mehr, weil Infinite von einer ebenso packenden wie vielschichtigen Erzählung lebt. Spielemacher Ken Levine vereint große Themen wie Schuld, Sühne und Rassismus und erschafft eindrucksvolle Charaktere, die lange im Gedächtnis bleiben – allen voran Elizabeth, die ebenso charmant wie gefährlich ist. Ihr dynamisches Verhalten ist beeindruckend, wenn sie Booker beim Suchen unterstützt, ihm Munition zuwirft sowie Zugang zu Geschützen oder Deckung ermöglicht.
A la fois plus et moins qu'un shooter, BioShock Infinite accroche et fascine tout en offrant une vision d'une rare intelligence, sans concession, sans manichéisme primaire, le tout serti dans un magnifique écrin. Bref, une chose est sûre, ceux qui s'envoleront pour Columbia ne sont pas près de remettre les pieds sur terre.
Avouez que ce serait cocasse... En tout cas une chose est sûre, ce DLC est absolument indispensable pour tous les fans de BioShock Infinite et, paradoxalement, encore plus pour ceux du BioShock originel. Comme un terrible écho aux récents déboires du studio Irrational Games, la saga trouve ici une véritable conclusion, et nous laisse l'impression d'un travail pleinement accompli, achevé, et cohérent. Un bien beau baroud d'honneur !
De manier waarop het verhaal in BioShock Infinite wordt verteld is in ieder geval beter dan in het origineel. Het verrassingselement dat de eerste BioShock had is niet meer te herhalen en vooral in dat opzicht is Infinite dus de betere game. Het is een ervaring die iedere gamer meegemaakt moet hebben en aan het einde zul je net als ons met open mond naar je beeldscherm zitten staren, onder de indruk van dit meesterwerk van Irrational Games.


Handel's Garden Goji Cream in Pakistan – As a Rule, Most People Suppose That There Is Only One Method to Fight Wrinkles and Other Signs of Aging. Individuals Discuss Botox And Plastic Surgery And Can't Believe That There Is An Innovational Brand-New Way To Hide Your Real Age And Look Younger. The Most Recent Discovery in the Beauty Industry – Goji Berry Facial Cream.
A Revolutionary Combination Of High Quality Ingredients Based On Hyaluronic Acid, Specifically Designed For The Care Of Aging Skin. Gluta White Pills Goji Berry Cream in Pakistan a Solution That Works for Problems Related to Aging: Wrinkles on the Forehead and between the Eyebrows, Crow's Feet, Laugh Lines, looseness And Loss of Elasticity, Pigmentation, Oval Deformed Face.
Goji Cream For Skin in Pakistan – Ultimate Whitening Mask These Amazing Results Are Related To The Natural Components Of The Cream Which Are Famous For Their Rejuvenation Qualities. Goji Cream in Lahore Contains Up To 7 Times More Vitamins And Minerals Than Similar Products. The Cream Stimulates Active Regeneration of Cells, Skin Gets Essential Nutrition and Preserves Its Natural Color.


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Q: Apache2 mod_rewrite, handling the optional "/" at the end of a URL I am attempting to host a single custom page to set as my homepage on my server.
The real path to the page is example.com/start.html.
However, I do not want this ugly URL in my homepage so I am trying to make it so that the path is example.com/start/.
My .htaccess file contents is:
<IfModule mod_rewrite.c>
    RewriteEngine On
    RewriteRule    ^start\/?$    start.html    [NC,L]
</IfModule>

This makes example.com/start redirect properly, but example.com/start/ leads to a 404 error (emphasis on the slash at the very end of the URL).  The error I get is:
The requested URL /start.html/ was not found on this server.

I believe that my regex in the RewriteRule is correct (where it should accept either "start" or "start/", so I am not sure what the problem is.
I would appreciate any help with this issue.

redpajama_set_name: RedPajamaStackExchange


text:
Q: Joining two nodes using SKPhysicsJointFixed in SpriteKit I want to create a fixed connection between two nodes using SKPhysicsJointFixed.
Code:
let joint = SKPhysicsJointFixed.joint(withBodyA: bodyA, bodyB: bodyB, anchor: anchor)
physicsWorld.add(joint)

Before (without joint):

After (using code above):

It seems that I've calculated everything correct since the line in the middle clearly shows the connection I wanted to create. However there's now a second line, pointing to the far left and affecting (?) the elements physical behavior.
How would I connect these two nodes instead / what am I missing here?


Welcome home to 6243 Orchard Lane! One of the best blocks in Cincinnati with friendly neighbors and holiday celebrations that are second to none!
Timeless Jewel in the Crown of Pleasant Ridge! One of a kind Tudor w/ rich architectural details- wrought iron railing, natural moldings, chiseled stone work, leaded glass. Gorgeous LR anchored by an etched stone fireplace . Gleaming HDWD flrs, huge lot &rear entry 2 car garage w/ parking pad. MBR w/ beamed vaulted ceiling & updated en suite.


text:
Q: Convert a Byte Array to String in Silverlight? I'm trying to convert a byte array to a string in Silverlight, but I get the following compilation error:
'System.Text.Encoding.GetString(byte[])' is inaccessible due to its protection level
This is the method that I'm using:
string text = UTF8Encoding.UTF8.GetString(myByteArray);

How else can I achieve this?

A: You can write:
string text = UTF8Encoding.UTF8.GetString(yourByteArray, 0, yourByteArray.Length);

Silverlight 3 and 4 only support that override.

A: string text = Encoding.UTF8.GetString(myByteArray,0,myByteArray.Length);

Works in SL4, don't know about anything earlier.

A: You May use Inicode encoding also,
   String text=(new UnicodeEncoding()).GetString(barray, 0, barry.Length)

By this way you are able to get as string from byte[],
vice versa by
   Byte[] myarray=(new UnicodeEncoding()).getBytes(Stringexpressin);


This attractive manufactured housing community offers 21 dwellings and an additional vacant lot. All units are owner-held and rented on long-term leases. Owner has self-managed and taken great care to ensure the community is well-maintained throughout. Call for more information - please do not drive through without speaking to an agent for special instructions.


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Prioziorni (Uliànovsk), localitat de la província d'Uliànovsk, a Rússia
 Prioziorni (Volgograd), localitat de la província de Volgograd, a Rússia


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Analyzing Glacier Surface Motion Using LiDAR Data
UAV-Based Oblique Photogrammetry for Outdoor Data Acquisition and Offsite Visual Inspection of Transmission Line
Can We Go Beyond Burned Area in the Assessment of Global Remote Sensing Products with Fire Patch Metrics?
10.3390/rs9030279
Fraser, R. H.
Van der Sluijs, J.
Hall, R. J.
Remote Sens. 2017, 9(3), 279; https://doi.org/10.3390/rs9030279
Calibrating Satellite-Based Indices of Burn Severity from UAV-Derived Metrics of a Burned Boreal Forest in NWT, Canada
by Robert H. Fraser 1,* , Jurjen Van der Sluijs 2 and Ronald J. Hall 3
Canada Centre for Mapping and Earth Observation, Natural Resources Canada, Ottawa K1S 5K2, ON, Canada
Centre for Geomatics, Government of the Northwest Territories, Yellowknife X1A 2L9, NT, Canada
Canadian Forest Service, Natural Resources Canada, Edmonton T6H 3S5, AB, Canada
Academic Editors: Diofantos Hadjimitsis, Ioannis Gitas, Luigi Boschetti, Kyriacos Themistocleous and Prasad S. Thenkabail
Received: 9 February 2017 / Accepted: 13 March 2017 / Published: 16 March 2017
Wildfires are a dominant disturbance to boreal forests, and in North America, they typically cause widespread tree mortality. Forest fire burn severity is often measured at a plot scale using the Composite Burn Index (CBI), which was originally developed as a means of assigning severity levels to the Normalized Burn Ratio (NBR) computed from Landsat satellite imagery. Our study investigated the potential to map biophysical indicators of burn severity (residual green vegetation and charred organic surface) at very high (3 cm) resolution, using color orthomosaics and vegetation height models derived from UAV-based photographic surveys and Structure from Motion methods. These indicators were scaled to 30 m resolution Landsat pixel footprints and compared to the post-burn NBR (post-NBR) and differenced NBR (dNBR) ratios computed from pre- and post-fire Landsat imagery. The post-NBR showed the strongest relationship to both the fraction of charred surface (exponential R2 = 0.79) and the fraction of green crown vegetation above 5 m (exponential R2 = 0.81), while the dNBR was more closely related to the total green vegetation fraction (exponential R2 = 0.69). Additionally, the UAV green fraction and Landsat indices could individually explain more than 50% of the variance in the overall CBI measured in 39 plots. These results provide a proof-of-concept for using low-cost UAV photogrammetric mapping to quantify key measures of boreal burn severity at landscape scales, which could be used to calibrate and assign a biophysical meaning to Landsat spectral indices for mapping severity at regional scales.
forest fire; burn severity; composite burn index; normalized burn ratio; unmanned aerial vehicle; UAV; UAS; Landsat
Wildfires are a major cause of disturbance in North American boreal forests, burning an annual average of approximately 10,000 km2 in the 1960's and more than 31,000 km2 in the 1990's [1]. There is high interannual variability in the area burned [2], and boreal fires can exert a considerable influence on the species composition, diversity, and stability of many forest ecosystems [3]. Fires can cause large fluxes of carbon within an ecosystem [4] and release a tremendous quantity of carbon to the atmosphere [5]. This can lead to a boreal forest becoming a significant net carbon source, particularly when combined with severe insect disturbances [2]. The near-complete mortality of forest vegetation after boreal fires in North America has modified wildlife habitats, including the elimination of lichen that caribou forage upon [6]. In colder permafrost environments, the active layer depth also often shows a long-term increase after a fire, due to the removal of the insulating surface organic layer [7]. Of particular concern is the projected increase in the area, frequency, and severity of fire under a changing climate, and its potential to exacerbate changes in vegetation succession and ecosystem function [8,9,10].
Burn severity is a term used to describe the magnitude of ecological change caused by fire [11]. Knowledge of burn severity is important for predicting the post-fire vegetation community [12], assessing the availability of residual seed sources to promote regrowth [13], predicting long-term forest successional patterns [13], and determining changes in bird abundance [14]. Boreal burn severity has been assessed in North America using a variety of methods that span spatial scales from plot measurements [15,16,17], to high resolution air photos [18], airborne hyperspectral imagery [19], airborne Lidar [20], and satellite imagery for mapping at landscape to regional scales [21].
A commonly applied field method for assessing burn severity in forests is the Composite Burn Index (CBI) [22]. The CBI provides a numerical index of vegetation damage from fire by integrating visual estimates of damage, stratified by five vertical layers (substrate, herbs and low shrubs < 1 m, tall shrubs and saplings 1–5 m, sub-canopy trees, and canopy trees), using a scale of 0 (unchanged) to 3 (high severity). The CBI provides a rapid means of assessing burn severity that integrates a variety of ecologically significant burn severity indicators. Some limitations and challenges in applying the CBI include: (1) the qualitative nature of its assessments, which could vary among observers [23]; (2) the difficulty and cost involved in accessing remote burn sites on the ground; (3) the potentially large number of plots required to represent the range of conditions in a large, heterogeneous burned area; (4) a need to infer pre-fire fuel conditions for assessing consumption and mortality [23]; and (5) a limited ability to quantify organic layer consumption [24], which is an important measure of severity in northern boreal forests. Despite these limitations, the CBI is a widely used field method in burn severity assessment [23].
A wide range of satellite-based approaches have also been developed to map burn severity over larger forested areas [11,25,26]. A common method is to compute the difference between the pre-fire and post-fire Normalized Burn Ratio (NBR), which is based on the near-infrared and shortwave infrared bands from 30 m resolution Landsat imagery [21,22]. The difference in the NBR (dNBR) has been effective for mapping burn severity in Canadian forests [16,27,28], but less so for Alaskan spruce forests [29,30], where the severity strongly depends on the depth of burning in the surface layer [29]. Since dNBR only measures a spectral response change, it is the calibration with the plot-based CBI that provides the ability to transform larger-area dNBR values into maps of varying burn severity [22]—an approach that has been applied across different regions of boreal forest [21]. For example, a non-linear relationship between CBI and dNBR was derived for several boreal fires within Western Canada, by Hall et al. [16]. Some considerations for applying this CBI-Landsat calibration approach include: (1) the requirement to identify CBI plots that should be relatively homogeneous at a 90 m, 3-by-3 Landsat pixel scale; (2) the need for cloud-free, post-burn Landsat imagery that closely matches the CBI sampling date; and (3) an understanding of the complex physical relationship between CBI's multiple, integrated measures of severity and spectral changes, measured using satellite-based indices [11,23,31].
Driven by a need to acquire highly detailed information over larger areas, relative to field plots, unmanned aerial vehicles (UAVs) have been growing in popularity as a means of conducting inexpensive, on-demand remote sensing that can bridge measurement scales between field plots and satellite imagery [32]. While there have been a number of applications of thermal sensors on UAVs to map actively burning fires [26], there has been a limited use of UAVs for assessing vegetation burn severity. One application involved the use of a multispectral imager mounted on a large, military-grade UAV system, to generate NBR maps in the Western US [33]. More recently, a post-fire digital terrain model (DTM) derived from a UAV survey was differenced with a pre-fire DTM from airborne LiDAR, to estimate the depth of surface burning in a tropical peatland [34]. The purpose of our study was to assess the potential for using a small, multicopter UAV to map indicators of boreal forest burn severity at landscape scales, and to up-scale this information to calibrate Landsat spectral indices, thus representing biophysically meaningful measures of severity over larger areas. As a result, we also conducted a limited comparison of plot-based CBI values with both UAV and Landsat indices of burn severity.
2.1. Study Area and Fires
This study was conducted 120 km southwest of Yellowknife, NWT, Canada, at three sites within 3 km of each other that burned during summer 2014 (Figure 1). The affected forest lies within the Great Slave Plain High Boreal Ecoregion, which contains closed to open canopy stands of pure and mixed tree species, comprising jack pine (Pinus banksiana Lamb.), white spruce (Picea glauca (Moench) Voss), black spruce (Picea mariana (Mill) B.B.P.), and trembling aspen (Populus tremuloides Michx.) [35]. A widespread fire outbreak occurred in NWT in 2014, during extreme fire danger conditions that affected 3.4 million ha of forest lying primarily in the region surrounding Yellowknife. CBI plot measurements collected by the Canadian Forest Service and Government of NWT at select burned sites (n = 54) in the larger region, had an average combined CBI score of 2.03, indicating a moderate-to-high average burn severity. These plots were surveyed in summer 2015 and 2016, according to the methods described in Hall et al. [16]. Similar to [36], we believe that the sampling of some sites two years after the fire did not negatively impact our ability to determine burn severity in this moderate-to-high severity burn. The CBI estimates of both years were combined into a single dataset for analysis with the remote sensing indices. We used UAV and satellite sensor data collected in the summer following burning to provide an extended assessment of severity that accounted for delayed mortality and early vegetation regeneration [22].
2.2. UAV Imagery and Processing
UAV-based photographic surveys of the burned study sites were conducted on the 4–5 August 2015 using a PX8 octocopter developed by Xpedition Robotics. This octocoper carried the Pixhawk flight controller running Arducopter 3.2 software and a 24 megapixel Sony a6000 mirrorless camera with a 20 mm Sony pancake lens. Mission Planner software was used to plan autonomous flights at 90 m above ground level in a grid pattern, to capture nadir imagery with ~2 cm resolution (Figure 2), 85% forward overlap, and 68% side overlap. Three separate burned sites containing a range of severities and fuel types were surveyed (Table 1). A recent forest inventory by the Government of NWT, based on 2013 air photos, was used to identify the dominant pre-burn tree species within each survey area.
The highly overlapping UAV photos were processed into dense 3D point clouds, 3 cm resolution digital surface models (DSMs), and 3 cm resolution colour orthomosaics, using Pix4d mapper v2.0 software. Pix4d uses proprietary Structure from Motion (SfM) algorithms in an automated workflow to match common features (keypoints) between corresponding images, apply a photogrammetric bundle adjustment, and create dense 3D point clouds using multiview stereo matching [37]. The specific settings used for Pix4d point cloud generation were: a half image-scale, optimal point density, and a minimum of two matches, which resulted in point cloud densities of about 200 points per m3. The point clouds were used in Pix4d to create DSMs representing the upper surface of all scene features, which could then be applied to ortho-rectify and mosaic the photos, thus generating orthomosaics. LAStools software was used to denoise and classify the point clouds into ground and non-ground objects, before triangulating and then rasterizing the ground points into a bare earth (or digital terrain) model. The heights of non-ground objects (e.g., all shrubs, dead-standing boles, green canopies) were normalized, relative to the bare earth elevations (e.g., mineral soil, scorched moss, completely horizontal deadfall), which were subsequently triangulated and rasterized into a vegetation canopy height model that represents the heights of all objects above ground level.
We focussed on two basic indicators of burn severity (residual green vegetation and charred organic surface) that could be readily separated using UAV-based colour photographs and are known to have a strong relationship to remotely sensed reflectance [19,38]. These UAV-based indicators are also analogous to the subset of CBI factors that measure the surface duff condition (i.e., charring), the frequency of surviving vegetation, and the percentage of unaltered crown foliage [22]. Several visible-channel spectral indices were computed from the UAV orthomosaic digital numbers [39] (Table 2), to classify charred surface and green vegetation, which may represent either residual unburned moss and other vegetation, or early regeneration one year after a fire. A reference sample representing burned areas (100 polygons containing 5311 pixels), and green ground and tree canopy vegetation (100 polygons containing 3792 pixels), was manually digitized within the largest survey region (#1), with the aid of the raw 2 cm resolution UAV photos and ground photos from three CBI plots. These samples were used to compare the effectiveness of the different UAV indices for separating green vegetation.
2.3. Satellite Imagery and Processing
Pre- and post-fire 30 m resolution Landsat-8 images were used to compute the post-fire NBR (post-NBR) and the differenced Normalized Burn Ratio (dNBR) [22] (Table 2). Two Level-1T images from Path 48 Row 17 were acquired from USGS GloVis for 17 July 2013 and 23 July 2015, that provided near-anniversary, cloud- and smoke-free coverage of the surveyed sites. Radiance values were calibrated and converted to top-of-atmosphere reflectance channels using USGS coefficients following [40], and these were used to compute the burn severity indices.
The first three UAV spectral indices in Table 2 were assessed for their ability to discriminate green vegetation from all other surface types, using a simple statistic (S) that provided a measure of the index signal-to-noise ratio. A value greater than 1 indicates that the standard deviations of an index for separating burned surfaces and green vegetation do not overlap, allowing reasonable class separation [41].
S = |xb − xg|/sb + sg
where S = separability statistic, xb = mean UAV index value from burned surfaces, xg = mean UAV index value from green vegetation, sb = standard deviation of index from burned surfaces, and sg = standard deviation of index from green vegetation.
A simple Jenks classifier was applied to the spectral index that provided the highest separability, to create a binary burned/green vegetation map. The Jenks classifier determined a class break value that produced two natural groupings by minimizing each class's average deviation from its mean, while maximizing each class's deviation from the other class's mean.
A new UAV-based index called the Char Index was formulated, to highlight charred organic surfaces (Table 2). This is a composite index based on the observation that charred surfaces have a very low visible reflectance (quantified using a Brightness Index) and a flat visible reflectance spectrum that produces the characteristic lack of colour [42] (quantified using a Maximum RGB Difference Index or MaxDiff). A multiplier of 15 was applied to the MaxDiff term to give it a similar weighting in the additive index. A threshold value of the Char Index was derived interactively, using the UAV imagery as a reference to create a binary map of dark, charred surfaces. A tree shadow mask was applied to the index to exclude shadows, which also have low Char Index values. We found that shadows could be effectively separated from all other cover types, including the charred surface, when applying a two-class Jenks classifier to the red channel (Figure 3d).
The 3 cm resolution map of green vegetation derived using the optimal greenness index was aggregated within the footprints of overlapping 30 m resolution Landsat pixels, to compute a fraction of green vegetation cover (i.e., Green Fraction). Similarly, the charred vegetation classification was aggregated to derive a 30 m char fraction (i.e., Char Fraction). Of interest was a statistical comparison of the up-scaled UAV-based indicators of burn severity and the Landsat burn severity indices. The UAV vegetation canopy height model was also used to separate green tree crown vegetation (>5 m) in the binary green vegetation classification (i.e., Green Tree Fraction). It is worth noting that direct georeferencing of UAV photos using the onboard GPS typically provides 1–2 m accuracy in the generated orthomosaic [43], compared to 12 m CE90 registration accuracy for Level-1T Landsat-8 imagery. Therefore, co-registration of the two datasets should normally be within 14 m, or one-half of a Landsat pixel.
The 30 m pixels that comprised each of the three study areas (Table 1) were randomly partitioned into model calibration (70%) and validation (30%) data sets. These data sets were then compared using a two sample Kolmogorov-Smirnov test, to determine whether the empirical distribution functions were statistically similar [44]. Several non-linear regression functions were examined using Data-Fit, a curve fitting and data plotting software tool by Oakdale Engineering, to find the optimal model form of best fit throughout the range of data, for both post-dNBR and dNBR as predictors of the UAV burn severity indicators (i.e., by comparing the coefficient of multiple determination—adjusted R2, root mean square error—RMSE, significance of model coefficients, simplicity of model form, and graphical plots of model functions). The selected model was applied to the validation data set, from which the predicted values were evaluated using the Wilcoxin signed-rank test to test for statistical differences at the 5% level of significance. Standardized residual plots using the validation sample were also constructed, to obtain insights into the distribution of the residuals over the range of post-dNBR and dNBR.
The binary, UAV-based maps of green vegetation, green crown vegetation, and charred surface, were also separately aggregated within the 30 m extents of the 39 of 54 CBI plots that were collected within the study burns. This allowed for a separate comparison of the UAV metrics and Landsat indices to the CBI burn severity scores, by again examining a range of non-linear regression functions.
The separability statistic (S) derived for each UAV index indicated that the Excess Greenness (ExG) index (Figure 3b) provided the best discrimination of the burned and green vegetation samples (S = 2.2), followed by NormG (S = 1.9) and NormG-R (S = 1.0). We therefore applied the binary classifier to ExG and assessed the resulting map accuracy (Figure 3c) using the reference samples. The natural breaks (Jenks) classification produced a very high accuracy, with only 68 of 5268 (1.3%) burned samples and 5 of 3794 (0.13%) unburned samples being classified incorrectly. This high accuracy is the result of the two classes' ExG mean values being separated by more than two standard deviations (S = 2.2), and the fact that reference samples were selected with a relatively high confidence and did not include borderline cases, such as partially scorched crowns.
The two-sample Kolmogorov-Smirnov test indicated that the probability distributions of UAV and Landsat index values from the model calibration (70%) and validation (30%) datasets were significantly similar (p-values 0.32–0.64). A non-linear, exponential function in the form Y = abx was found to be suitable for modeling the relationships between the two Landsat severity indices (post-NBR and dNBR) and three UAV severity indicators (percent green fraction, percent green fraction above 5 m, and percent char fraction).
Figure 4 shows the scatterplots, best-fit exponential equations and lines, coefficients of determination (R2), and root mean squared errors (RMSE) for these six modeled relationships. The post-NBR showed stronger relationships with both the green tree fraction (Figure 4b; Adjusted R2 = 0.81) and char fraction (Figure 4c; Adjusted R2 = 0.79), while the dNBR was more closely related to the total green fraction (Figure 4d; Adjusted R2 = 0.69). Initial visualizations of the scatterplots in Figure 4 may suggest that there is a possible pattern of increasing residual error with changing post-NBR or dNBR values, but standardized residual plots proved otherwise. Example standardized residual plots for Figure 4e,f, where this pattern appeared most obvious, do not depict a pattern of increasing variance across the range of dNBR (Figure 5a,b, respectively). The Wilcoxin signed-rank test also showed no statistical differences (p > 0.05) in the predicted versus actual green and char fractions from the 30% validation sample (n = 167), when these were predicted using the models developed from the 70% training sample (n = 388) (Table 3). However, green tree fraction predictions were statistically different (p < 0.05) from either Landsat predictor (Table 3).
Non-linear models for predicting the overall CBI using the Landsat indices and UAV severity indicators are summarized in Table 4. The post-NBR and dNBR Landsat indices could explain similar amounts of CBI variance (Adjusted R2 = 0.53–0.59), with relationships that were somewhat weaker (Adjusted R2 = 0.82–0.85) than those reported in [16], based on dNBR. The results also indicated the UAV green fraction indices were comparable to the Landsat indices in their ability to predict the CBI.
Previous studies of boreal forest burn severity have shown that the Landsat dNBR index generally demonstrates the strongest relationship to the field-based CBI designed to measure overall burn severity [21]. The NBR exhibits a large drop after burning, owing to the removal of leafy vegetation, which decreases NIR scattering, SWIR water absorption and canopy shadowing [22,45]. In this study, we similarly found that dNBR was effective for predicting CBI (Table 4), but also demonstrated that Landsat indices were even more closely related to specific indicators of burn severity derived from UAV mapping (Figure 4). The post-NBR and dNBR indices could each explain a similar amount of the variation in the UAV-derived green vegetation fraction, while the post-NBR was a better predictor of the UAV char fraction. These Landsat-UAV relationships are consistent with [38], where Landsat severity indices were most highly correlated to the green crown fraction and total charred ground surface from a set of 32 fire effect field measures from Alaska.
It is important to note that the strongest modeled relationship was for the UAV green tree fraction predicted using the post-NBR (Figure 4b). Despite the strength of this relationship, the high degree of flattening at low post-NBR values makes it relatively less useful as a means to calibrate the NBR, compared to the total green fraction or char fraction relationships. The major reason for this is that the large proportion of crown fire within our study sites led to a majority (57%) of 30 m Landsat pixels containing less than five percent green tree crown (Figure 6, FP15_21). As a result, this UAV indicator had a relatively minor influence on 30 m post-NBR values over most of the post-NBR range.
Superimposing a raster of the regression model residuals over the UAV orthomosaic can provide insight into the specific reasons for scattering in the model results shown in Figure 4. An examination of the residuals for the first plot (post-NBR vs. green fraction) shows that values are often spatially clumped, rather than random. While there don't appear to be consistent causes for either model over- or under-prediction of the UAV green fraction, some patterns are apparent. For example, some areas where the actual UAV-derived green fraction is higher than the Landsat-predicted fraction (i.e., underestimation) are associated with relatively open and unburned canopies that contain fewer shadows, which may otherwise obscure unburned ground vegetation (Figure 6, FP15_20). This can result in a higher UAV-mapped green fraction compared to areas where shadows obscure more of the ground surface. By contrast, some areas where the actual green fraction is lower than the amount predicted (i.e., overestimation) correspond to standing scorched tree canopies with brown/orange needles (Figure 6, FP15_19), or with a ground layer of dropped needles (Figure 6, FP_22). These canopies encountered a less severe fire at the surface and lower canopy strata, but it was severe enough to scorch the needles through proximal heating, without direct flame contact. The Jenks classifier was used to create a binary, burned versus green vegetation classification, whereby scorched crowns were not treated as a separate, less severe vegetation response class.
Most Landsat-based studies of boreal burn severity have applied the dNBR, which is a bi-temporal index representing spectral changes from pre- to post-fire conditions [16,21,27,28]. However, investigations in Alaska, where black spruce is the predominant tree species, have shown that the post-NBR can be more highly correlated than the dNBR to field-measured fire effects [29,38,46]. The choice of a uni- or multi-temporal index to characterise severity should be based primarily on the accuracy for measuring fire effects, but may also reflect other considerations. For example, an index that measures spectral changes such as the dNBR, should be theoretically preferable for studies of burn severity, since, by definition, this term describes the degree of ecosystem change resulting from fire. The CBI, which was developed as a field measure of severity for calibrating dNBR, is similarly based on ecological changes, although pre-fire conditions must often be inferred [22,23]. A bi-temporal index also permits a more accurate mapping of the extent of burning (a pre-requisite for determining severity), by avoiding commission errors over unvegetated areas that can result from only using a post-fire index. In our study, the post-NBR and dNBR were comparable in their ability to predict UAV-based green vegetation fractions, while the post-NBR was a better predictor of the UAV char fraction. The better performance of the post-NBR may be due, in part, to the char indicator having little or no dependence on the pre-burn conditions that influence the dNBR values. The inclusion of a pre-burn NBR to generate the dNBR has the potential to add spectral variability unrelated to fire, due to image differences in solar illumination, atmosphere, phenology, and spatial registration [31,47], or differences in the pre-fire forest condition [48]. Based on these results, a potential strategy for upscaling the UAV indicators using Landsat imagery may be to use the dNBR for mapping the extent of fires and green vegetation fractions, followed by the post-NBR to estimate char fractions.
The strong relationship between the dNBR/post-NBR and the UAV-derived severity indicators, permits the translation of the Landsat indices into measures of burn severity with a greater biophysical underpinning. Figure 7 shows the pre- and post-fire Landsat image and predicted residual green vegetation and char fractions based on the NBR-UAV non-linear regression functions, for a larger 60 km2 area within our study region. Considering the diversity of the fuel types sampled (Table 1) and the results from the hold-out validation sample, these regression relationships should be applicable to other areas within in the post-burn Landsat image that burned under similar conditions. However, the relationships may not be valid for other images captured at different post-fire regeneration intervals, and should also be tested for their extendibility over a wider range of forest ecological conditions [16,21].
The area of charred surface was derived from UAV mapping to indicate the extent of burning in the surface organic layer. A second potentially useful metric of surface burning not investigated here, is the presence of light coloured ash, which indicates that the fire has completely combusted organic material, such as large woody debris. The amount of ash cover has been related to surface fuel consumption in the boreal forest [19,49], and could thus provide a valuable UAV-based measure of burn severity in the surface layer. The extent of light ash could potentially be derived using a colour index similar to our Char Index, but by identifying a bright, rather than dark, colourless surface. However, note that ash, unlike char, could be challenging to separate from other surfaces such as bright rock, based on colour alone. A very high resolution digital surface model derived from UAV photogrammetry and/or image segmentation techniques could potentially assist with this [39]. Ash cover can also be rapidly removed by wind and rainfall, so UAV surveys may need to be conducted relatively soon after burning. The mapping of light ash would be a more important consideration for boreal burns containing larger proportions of ash than were encountered in our study sites [50], and where it would be more likely to influence Landsat burn indices at a 30 m scale [42].
In this study we made limited use of the UAV-based vegetation height model to separate the portion of residual green vegetation that lies above 5 m in the tree canopy. A vegetation height model could be further exploited to stratify UAV severity metrics according to the five CBI height classes, in an attempt to mimic specific factors that form the overall CBI rating. UAV-based colour and height information could also be investigated, to quantify more complex indicators of burn severity, including the area of scorched needle-leaf crowns, char height [51], density of standing and downed boles with no foliage, and the presence of exposed mineral soil arising from the complete combustion of surface organic material. The calculation of these metrics may require higher resolution UAV photos with a larger overlap than those collected in this study [39], to facilitate characterizing the detailed structure of residual dead and living trees. The goal of follow-on research should therefore focus on a more comprehensive UAV-based protocol for plot-scale assessments of burn severity, which could include select field-measured attributes, such as depth of surface burning [15,17], that may be difficult to address using UAV photogrammetry alone. If successful, the major advantage of such a hybrid protocol would be the ability to conduct more quantitative, repeatable, and objective burn severity assessments with a closer physical linkage to satellite-based indices, to allow for robust up-scaling.
Some other potential applications of UAV-based, SfM modeling for studying boreal fires include: (1) providing reference data for training and validating burned area mapping algorithms that use Landsat's or higher resolution satellite sensors; (2) mapping the charred standing bole density to help guide post-fire salvage logging efforts; and (3) quantifying long-term regeneration rates and structural changes in recovering burned forest, similar to previous studies that have used LiDAR [20]. Because of the relatively limited extents that can be surveyed using UAVs, relative to manned aircraft or satellite-based sensors, these applications would have to examine sites that had been carefully chosen to represent larger-area conditions.
Finally, the development of UAV-based burn severity indices in this study was not without certain limitations and challenges. Here we highlight several:
Our surveys were conducted under clear, sunny conditions that caused strong shadows to cover much of the ground in areas with dense residual tree cover. Shadowing could be minimized by conducting surveys in light, overcast conditions.
Surface char was completely obscured in some areas, due to a dense layer of scorched conifer needles that dropped from the above canopy.
We did not validate the accuracy of the tree canopy height model and assumed that it was sufficiently accurate for broadly separating ground-level vegetation and tree crowns that lie above 5 m. For reference, Wallace et al. [52] created UAV/SfM-based canopy height models that could estimate 4.7–16.2 m eucalyptus tree heights, with a root mean square error of 1.3 m.
The binary Jenks classifier, used for separating both green vegetation and shadows, was found to be simple and effective, yet may not be as accurate as more advanced classifiers or those that include a third, less severe vegetation response class for brown/orange scorched canopies.
A rigorous validation of very high resolution, UAV-derived indicators of burn severity is challenging, because of the requirement to collect reference data that is at least as detailed and spatially precise. The approach used in this study for mapping green vegetation and char was to relate photo-interpreted conditions, based on ground and UAV photos, to a georeferenced UAV orthomosaic. However, the validation of more advanced and structural measures of burn severity from UAV photogrammetry will require precisely georeferenced field-based measurements.
We used a consumer-grade RGB camera mounted on a UAV to capture images in JPEG format, that provided simple digital number intensity values. Note that such data have an unknown relationship to scene radiance [53], and would be impacted by any changes in solar illumination during a survey. While we found that such imagery is suitable for separating broad and distinct classes, such as green vegetation and charred surface, more detailed vegetation characterization could benefit from using miniaturized multi- or hyper-spectral instruments that provide additional spectral information, and where radiance is normalized based on incident light sensors. Note, however, that such sensors currently provide coarser pixel resolutions (e.g., 1–2 megapixels) that may make the SfM modeling of a tree structure challenging.
Our results demonstrate that UAV-based photographic surveys and SfM processing methods can provide cost-effective, georeferenced information related to two basic indicators of boreal forest burn severity: the fraction of green vegetation, which includes both residual and regenerating plants, and the fraction of charred organic surfaces. These indicators were highly related to Landsat spectral indices (dNBR and post-NBR) commonly used to assess burn severity, which then permits assigning a biophysical scale to these indices at regional levels. We also found that the UAV severity metrics were similarly correlated to the plot-based CBI, compared to Landsat indices. The operational flexibility of UAVs ensures that mapping can be timed to closely match the acquisition of Landsat satellite imagery used in an extended post-burn assessment. Follow-on research will investigate additional, more complex measures of burn severity that make greater use of a vegetation height model to characterize the post-burn vegetation structure.
We thank Rob Skakun from the Canadian Forest Service and Kathleen Groenewegen from the Government of Northwest Territories for assisting with collecting CBI plot data, Kathleen Groenewegen for providing forest inventory data, and Ian Olthof from CCRS for assistance in processing the Landsat imagery. Tim Lynham and Ian Olthof provided helpful comments to improve the manuscript. This work was supported by Polar Knowledge Canada and NRCan's TRACS project led by Stephen Wolfe.
Robert H. Fraser and Jurjen van der Sluijs conceived the study,and acquired and processed the datasets; Robert H. Fraser led the spatial data analysis and wrote the first draft of the manuscript; Ronald J. Hall led the statistical analysis; and all authors were responsible for the research design, interpreting the results, and the writing and editing of the manuscript.
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Figure 1. Location of study area in Northwest Territories (blue circle) showing the extent of regional burning in 2014 (dark red patches), visible in a Proba-V satellite image composite from September 2014.
Figure 2. Portion of a 24 megapixel photo taken over survey area #3 using a Sony a6000 camera mounted to an octocopter UAV. Portions of the fire completely consumed the surface organic layer, exposing the bright underlying mineral soil.
Figure 3. Portion of study area #1 showing (a) a 3 cm UAV photo-orthomosaic within study area #1 with burned and green vegetation; (b) the UAV Excess Greenness Index; (c) a binary classification of green vegetation derived from thresholding the Excess Greenness Index; and (d) the Char Index, where more highly charred areas with a low index value appear orange-red and masked tree shadows are shown in black.
Figure 4. Scatterplots showing the relationships between the post-NBR and dNBR Landsat severity indices (x-axes) and three UAV-based severity indicators (y-axes), aggregated within the 30 m resolution Landsat pixel footprints. The best-fit exponential regression lines and equations are also shown for each relationship. The individual plots are post-NBR vs. green fraction (a), post-NBR vs. green tree fraction (b), post-NBR vs. char fraction (c), dNBR vs. green fraction (d), dNBR vs green tree fraction (e), and dNBR vs. char fraction (f).
Figure 5. Standardized residual plots derived from the fitted relationships shown in Figure 4e (a) and Figure 4f (b) depicting no bias and a homogeneous pattern across the range of dNBR.
Figure 6. Portion of the UAV orthmosaic for study area #1 (centered at 69.905°N, 116.53°W), showing the locations of four CBI plots with corresponding inset ground photos.
Figure 7. A 60 km2 area within our study region captured using (a) pre-burn Landsat-8 imagery from 17 July 2013; and (b) post-burn Landsat-8 imagery from 23 July 2015 (RGB = SWIR, NIR, Red); Predictions of percent post-burn green vegetation cover and percent charred surface cover, based on UAV calibration of Landsat burn indices, are shown respectively in (c,d).
Table 1. Details of the 2014 burned sites surveyed using an octocopter UAV in early August, 2015. The dominant tree species are listed in decreasing order of percent cover, where Sw = white spruce, Sb = black spruce, A = trembling aspen, and Pj = jack pine.
Survey ID
Surveyed Area (ha)
# UAV Photos
# 30 m Landsat Pixels
# Forest Inventory Units
Dominant Tree Species
# CBI Plots (2015, 2016)
1 49.7 1401 462 12 Sw, Sb, A 3, 24
2 9.3 285 66 2 Pj 1, 7
3 10.1 280 77 5 Pj, Sw, Sb 1, 3
Table 2. Description and formulation of UAV burn severity spectral indices, UAV burn severity indicators derived from the UAV indices, and Landsat spectral burn severity indices investigated in this study. NIR refers to Landsat's near infrared channel and SWIR2 refers to the second shortwave infrared channel centered at 2.2 µm.
Burn Severity Indices and Attributes
Channel Combination/Description
UAV spectral indices
Excess Greenness (ExG) 2G − R − B
Normalized Greenness (NormG) G/(R + G + B)
Normalized Green-Red Ratio (NormG-R) (G − R)/(G + R)
Brightness R + G + B
Maximum RGB Difference (MaxDiff) Max(|B − G|, |B − R|, |R − G|)
Char Index (CI) Brightness + (MaxDiff × 15)
UAV burn severity indicators
Green Vegetation From thresholding ExG index
Green Crown Vegetation Green Vegetation above 5 m
Charred Surface From thresholding Char Index
Landsat spectral indices
Normalized Burn Ratio post-fire (post-NBR) (NIR − SWIR2)/(NIR + SWIR2)
Differenced NBR (dNBR) NBRpreburn − NBRpostburn
Table 3. Test predictions for statistical differences (p = 0.05) from non-linear models employing independent validation samples using a Wilcoxin signed-rank test.
Landsat Severity Index (X)
UAV Measure of Severity (Y)
p-Values
post-NBR Green Fraction 0.74
Green Tree Fraction 0.00
Char Fraction 0.29
dNBR Green Fraction 0.93
Table 4. Best fit non-linear models for predicting the overall CBI using the Landsat and UAV severity indices.
Overall CBI Predictor
Non-Linear Model Y = Overall CBI
Adj R2
Landsat indices
post-NBR Ln (9.47–20.74 post-NBR) 0.59 0.60
dNBR 3.20 dNBR 0.63 0.53 0.64
UAV indices
Green Fraction (GF) 2.60–1.16 GF2 0.52 0.58
Green Tree Fraction (GTF) 2.70 × 0.96GTF 0.60 0.54
Char Fraction (CF) Ln (3.81–0.29 post-NBR) 0.36 0.67
© 2017 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license ( http://creativecommons.org/licenses/by/4.0/).
Remote Sens., EISSN 2072-4292, Published by MDPI AG


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