Scientists make first observation of Airy optical beams

first_imgSchematic of a 2D Airy packet. Image Credit: Georgios Siviloglou, et al. Scientists have made the first observation of an unusual class of optical waves called Airy beams. Unlike most types of light waves, Airy beams have the ability to resist diffraction over long distances, and can also freely accelerate during propagation. This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Researchers discover a way to generate an electron Airy beam Citation: Scientists make first observation of Airy optical beams (2007, November 29) retrieved 18 August 2019 from https://phys.org/news/2007-11-scientists-airy-optical.htmlcenter_img Explore further The researchers, Georgios Siviloglou, John Broky, Aristide Dogariu, and Demetrios Christodoulides from CREOL-University of Central Florida (UCF), hope that these unusual features may enable Airy beams to be used in applications such as particle manipulation and in nonlinear media. The group’s study, published in a recent issue of Physical Review Letters, reports the observation of Airy beams in both one- and two-dimensional configurations.Airy beams take their name from the “airy integral,” introduced by Sir George Biddell Airy in the 1830s to explain optical caustics such as those appearing in a rainbow. Airy beams were initially predicted in 1979 by two scientists, Michael Berry and Nandor Balazs, within the context of quantum mechanics. The scientists theorized the existence of a free particle described by the Schrödinger equation that could exhibit an Airy wave packet that doesn’t spread out as it propagates—in other words, it is diffraction-free. Remarkably, an Airy wave packet has the unusual ability to freely accelerate even in the absence of an external stimulus.“We are not sure why this absolutely fascinating prediction went unnoticed for so long given the fame of Michael Berry,” Christodoulides told PhysOrg.com. “We think that it is partly due to the fact that it was initially published in a relatively ‘obscured’ journal. The second issue has to do with experimental implementation. It is only very recently that we realized that exponentially truncated Airy beams have a Gaussian power spectrum and can thus be easily synthesized from standard Gaussian beams.”The UCF researchers noted that other two-dimensional diffraction-free light waves exist, such as the so-called Bessel beam, which is generated by a conical superposition of plane waves. Due to their non-diffracting nature, Bessel beams theoretically convey an infinite power. However, lack of space and power causes the beams to truncate and therefore diffract during propagation. In contrast to Bessel beams and other non-spreading waves, Airy beams do not result from conical superposition. Rather, the researchers generated Airy beams by using a computer-controlled spatial light modulator, which modulated the phase of a Gaussian beam, which was then imaged on a CCD camera. The scientists used different phase masks to generate either one- or two-dimensional Airy beams. The researchers observed that the local intensity features of the Airy beams tended to freely accelerate. This is because these beams are analogous to the probability wave function of a quantum mechanical particle when observed in a free-falling reference frame. Despite the beam’s center of mass remaining constant, the beam’s local intensity features follow a bent parabolic trajectory over distances up to 25-30 cm before experiencing diffraction. By contrast, a normal Gaussian beam of the same size would have expanded 24 times in this distance.“These beams have the ability to freely accelerate or self-bend during propagation while remaining invariant in shape,” Christodoulides explained. “Light is known to travel along straight paths. In contrast, in our case, the intensity features of Airy waves, follow parabolic or ballistic trajectories, very much like those of a projectile (fired from a canon) moving under the action of gravity.”The scientists explained that, due to the ability to separately adjust the x and y parameters of Airy beams, the acceleration of the non-diffracting beam can be controlled. The researchers also suggested that a slightly different technique for generating one-dimensional Airy wave packets may lead to the first observation of non-dispersing Airy pulses in optical fibers. Further, non-diffracting Airy beams may also be useful for particle manipulation or in nonlinear media.“These beams are highly asymmetric in their intensity,” said Christodoulides. “There are several applications in probing where this may be desirable. In addition, the fact that the main lobe of these beams (which conveys more than 50% of the beam’s energy) does not travel along straight paths can be used to ‘push’ particles sideways through radiation pressure.”More information: Siviloglou, G. A., Broky, J., Dogariu, A., and Christodoulides, D. N. “Observation of Accelerating Airy Beams.” Physical Review Letters 99, 213901 (2007). Copyright 2007 PhysOrg.com. All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of PhysOrg.com.last_img read more

Software automatically transforms movie clips into comic strips

first_img This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Copyright 2012 PhysOrg.com. All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of PhysOrg.com. (PhysOrg.com) — While some comics today are still drawn by hand, many modern cartoonists use a variety of digital tools to create comics. But even with the help of these tools, creating comics is a time-consuming task that requires many human hours of work. In a new study, a team of researchers has designed a program that can automatically transform movie scenes into comic strips, without the need for any human intervention. The researchers then conducted a user evaluation to see how well users understood and enjoyed the comics. They found that users had a slightly lower content comprehension of the comics compared with the original movie clips. Although some loss in comprehension is inevitable when converting to a different format, the script-face mapping errors also played a role. As for enjoyment, the user evaluations showed that enjoyment was highest when the comics included word balloons and effective layout and stylization. A comic page generated from a movie clip of “Titanic.” Image credit: Wang, et al. ©2012 IEEE Although the technique is capable of performing all steps automatically, the researchers noted that involving some human effort could lead to even better results. In such a scenario, the software would provide recommendations for each step of the transformation process, and humans could manually adjust the results much more quickly and efficiently than in pure manual methods. But the researchers also hope to improve the accuracy of the automated method.“We have two future plans,” Wang said. “One, improve the performance of each component, such as script-face mapping, and hope we can generate perfect clips without user interaction. Two, integrate speech recognition technology to generalize the software, such that we can generate comics without movie scripts (currently we need the script file of the movie clip, but by using speech recognition we can automatically transform speech to texts).” Explore furthercenter_img More information: Meng Wang, et al. “Movie2Comics: Towards a Lively Video Content Presentation.” IEEE Transactions on Multimedia. DOI: 10.1109/TMM.2012.2187181 A comic page generated from a movie clip of “The Message.” Image credit: Wang, et al. ©2012 IEEE Meng Wang, a professor at the Hefei University of Technology, China, and coauthors have published their study on the new software, which they call “Movie2Comics,” in a recent issue of IEEE Transactions on Multimedia.“The software can be useful for both professionals and hobbyists,” Wang told PhysOrg.com. “Professionals can directly use the software to generate comics (or integrate their interaction to achieve more impressive results); hobbyists may have interests to try it to see what will be generated from different movie clips.”As the researchers explain in their study, previous programs have been developed to assist cartoonists in converting movies into comics, but the new method is the first fully automated approach. Without the need for any manual intervention, the method has the potential to significantly cut the time and expense associated with creating comics.The new cartoonization process involves several steps, including an automatic script-face mapping algorithm that identifies the speaking character in scenes with multiple characters, automatic generation of comic panels of different sizes, positioning word balloons, and rendering movie frames in a cartoon style. The researchers used the new method to transform 15 movie clips into comic strips. The clips came from three movies – “Titanic,” “Sherlock Holmes,” and “The Message” – and varied in length from 2 to 7 minutes. Although the method performed the transformation well for the most part, it sometimes put word bubbles next to the faces of incorrect characters. The script-face mapping algorithm had an accuracy of 85%, which the researchers hope to improve. Citation: Software automatically transforms movie clips into comic strips (2012, March 14) retrieved 18 August 2019 from https://phys.org/news/2012-03-software-automatically-movie-comic.html PHD Comics hits the big screenlast_img read more

Pews fact tank studies American social networking

first_img More information: www.pewinternet.org/Reports/20 … ial-media-users.aspx Half of US adults using social networks: survey Credit: Pew Research Center Explore further (Phys.org)—The Pew Research Center, a “fact tank” on attitudes and trends that they identify, has issued a report from its Internet & American Life Project that slices and dices data on who uses social media. The portrait includes percentage shares according to ethnicity, age, and sex. “The Demographics of Social Media Users—2012” is a report that takes its data from a national survey conducted between November and December last year, in English and Spanish. Some of the findings are no surprise to those who generally follow social networking trends. Citation: Pew’s fact tank studies American social networking (2013, February 16) retrieved 18 August 2019 from https://phys.org/news/2013-02-pew-fact-tank-american-social.html They reflect what has been observed outside Pew in ubiquitous everyday instances of Internet use. Young adults, for example, are more likely than older adults to use social media, said Pew, a statement that is unlikely to draw gasps from media analysts. Internet users under 50 are particularly likely to use a social networking site of any kind, according to the report, and those ages 18 to 29 are the most likely of any demographic cohort to do so (83%).Men are less likely than women to be on the sites, and users in rural settings are less likely than urban-based users to use social networking. Another unastounding finding is that Facebook remains the most-used social networking platform. Two-thirds of online adults say they use Facebook—women more than men. As for Twitter, the percentage of Internet users on Twitter doubled since November 2010, now at 16%.The study does get interesting in looking at sites beyond Facebook and Twitter. Pinterest, described as an online pinboard, which launched as a closed beta in March 2010, attracted 15% of Internet users to its engaging virtual scrapbooking, in the survey. Pinterest is equally popular among users ages18 to 29 and 30 to 49. Women are about five times as likely to be on the site as men, the largest difference in gender of any site that was featured in this report.Survey findings for Instagram, a site that also launched in 2010, indicated that African-Americans and Latinos find Instagram especially appealing. Looking at Tumblr, the Pew survey found that it was significantly less popular among Internet users than the other social networking sites featured in the report. However, while just 6% of those online use the site, the Pew survey takers discovered that Tumblir is much more popular among the youngest cohort, with 13 percent of those ages 18 to 29 blogging on Tumblr.The sites, in terms of percent of users online, are as follows, as of December 2012: 15% of online adults said they use Pinterest; 13% of online adults said they use Instagram; 6% of online adults say they use Tumblr; 67% of online adults said they use Facebook; and 16% of online adults said they use Twitter. © 2013 Phys.org This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.last_img read more

A travelling film fiesta

first_imgGerman, French , Italian or anything from the world of european cinema is at your beck and call in the capital.‘It is easier to cross borders through art and music than economics or politics’, coming from a Europeon Union represenative, the statement symbolised the spirit of the 18th European Union Film Festival. Celebrating Women, the 11 city travelling film festival that was launched in Coimbatore on 8 March, is on its way to the capital on 8 May, trailing a voyage through Bangalore, Pune, Chennai, Goa and Mumbai. Also Read – ‘Playing Jojo was emotionally exhausting’In the curtain raiser for the festival, Pavel Svitil, Minister Counsellor – Deputy Head of Delegation of the European Union to India Jean-Philippe Bottin, Director, Alliance Française de Delhi, Angela Trezza, Director,  Italian Cultural Centre, Tibor Kovacs, Director of Hungarian Information and Cultural Centre, Jesús Clavero Rodríguez, Instituto Cervantes, came together to represent different EU member states. In an interaction, they dwelt upon the diveristy of Europe that will be portrayed through an assortment of 24 films produced in Europe over the last two years. In a deliberate effort, films of a certain nationality will be swapped and screened in a different cultural centre to embolden their message of cultural exchange and relationship. Also Read – Leslie doing new comedy special with NetflixThough the theme for the festival was decided long in advance, it happens to resonate with the current scenario in the capital. The screenings will share voices of women from across the European continent and offer an insight into their lives, their struggles and their persistance for being seen and heard.  The representatives assured that the films will have a cinematographic language that will hook the audience to the screen, however alien the languages be for  Indian audience. And ofcourse, you will get English subtitles to not lose the sense of meaning in between. Mark your dates for this one!DETAILWhen: 8- 19 May Where: Alliance Francaise, Instituto Cervantes, British Council, Hungarian Cultural Centre, Italian Cultural Centrelast_img read more

Urdu Drama Festival to begin on 13 Oct

first_imgThe Urdu Academy will be inaugurating the six-day Urdu Drama Festival on 13 October at Sri Ram Centre in Mandi House. To depict the composite lingual culture of Delhi, Urdu Academy started organising six days Urdu Drama Festival in the year 1988. Urdu Academy,  Delhi is the only organisation which has consistently organised Urdu drama festivals since last 26 years. The academy stages Urdu Plays in Urdu Drama Festival every year. More and more prominent drama troupes are coming forward now to stage Urdu Plays on a variety of topics such as social inequality, historical characters, students problems, communal harmony, the old culture of Delhi among others. This years’ Urdu Drama Festival is being dedicated to eminent scholar and writer Begum Qudsia Zaidi and Khwaja Ahmed Abbas.last_img read more

Rainbow routines

first_imgFive day long Indradhanush Dilli 2014 – A festival of Art concluded  on 16 November with Seminar and Prize distribution ceremony at Delhi Karnataka Sangh RK Puram and Vishwa yuva Kendra, chanakyapuri in Delhi. 850 child artiste including differently-abled children from 16 states and 52 young classical dance artistes showcased their talent in Indradhanush Dilli 2014.Sunaina – society for the upliftment of national arts of India, is an NGO dedicated to the propagation of the art forms hosted for the seven consecutive year Indradhanush Dilli 2014 – A Festival of Arts from 12 to 16 November. The topic of the seminar was ‘Energising the mind and body with traditional arts of dance and music’. The seminar was attended by many prominent speakers like Founder director of Sunaina and Bharat Natyam Exponent Guru Kanak Sudhaker, Bharat Natyam Exponents Jyotsna Shourie and Rama Vaidyanathan, Director Inst. For Empowerment of Persons with Multiple Disabilities, Neeradha Chandra Mohan and Odissi and chau dancer Shagun Bhutani.    Also Read – ‘Playing Jojo was emotionally exhausting’The five-day  dance festival was marked  by  wonderful performances by multi talented  850 child artiste and incredible performance of  52 artiste from all over India. The event hosted dance artiste from five year to 35 years age group. This event also saw great renowned names of Indian classical dances receive the award of Guru Samman.This year Sunaina felicitated Madhavi Mudgal, Jaylakshmi Eashwar and Evoor Rajendran Pillai. There were also performances of Odissi Dance by Debrabruta Barua Manipuri, Sudip Kumar Ghosh and troupe Kathak by Samantaa group Mohiniattam, Shruti K P and Kuchipuri by Avijit Das  on the inaugural day of Indradhanush Dilli 2014.  The  second day of the festival was marked by scintillating performance of  Vilasini Natyam by Vipanchi Rao, Bharatanatyam by Lakshita, Medha, Smrithi, Sathvikaa Kuchipudi Yakshagana by Pasumarthi Srinivasa Sarma and Troupe, and  Gaudiya Nritya by Ayan Mukherjee, Rachel Agnes, Parmita Banerjee, Ranjima Chatterjee and Sudeshna Majumdar. There were also  performances by  Bharatanatyam  dancer Aparajita Sarma. Also, differently-abled children from 16 states showcased their  talent in Indian dance, music and arts during the festival.last_img read more

Let the festivities begin

first_imgLe Meridian: is throwing a Christmas carnival is party for kids on Dec 25 noon onwards with surprise Santa’s all in white, Fun games, Christmas goodies for everyone one and many more.When : December 25, Where: Le MeridienShangri-La’s : Eros Hotel, Café Uno  New Delhi offers everything guests could wish for this festive season from tailor made room packages and a dazzling selection of dining offers, an enchanting atmosphere with cheerful rhythms and free flowing select beverages. Also Read – ‘Playing Jojo was emotionally exhausting’They can welcome the yuletide spirit with friends and family as the hotel unveils these special offerings this festive season.On Christmas Day, guests can savour a sumptuous and lavish brunch with family and friends for a memorable dining experience with a selection of traditional favourites including roasted lamb, traditional roasted turkey, yorkshire pudding and an indulgent array of desserts, such as Christmas puddings, plum cakes, fresh fruit tarts, carrot walnut slice with cream cheese amongst others at the hotel’s all day dining restaurant, Café Uno. Also Read – Leslie doing new comedy special with NetflixWhen: On till 25 December Prices: Rs. 3,500 plus taxes per personJaypee Hotels: As we approach the dawn of a? New Year,? prepare ?to ?surprise ?your? loved ones with a night full of ?spectacular celebration and entertainment at Jaypee Greens Golf and Spa Resort, Greater Noida. A perfect combination of? the? finest hospitality and world class facilities, Jaypee Greens Golf and Spa Resort is all set to create the ultimate luxury experience with its special ?New Year? packages. Where: Jaypee Hotels When: December 31(3 pm to 5pm)Eros Hotel: New Year Eve Celebration at Royal Ball Room inclusive of World Cuisine Gala Dinner with unlimited soft and alcoholic beverages (select brands), DJ and entertainments.Celebrate the spirit of the season with  gala buffet spread with unlimited premium beverages, live gigs, exciting travel deals, all this and more at Eros Hotel.Royal Ballroom – Put on your dancing shoes , lavish gala dinner  and premium beverages  to lift your festive spirits . Blooms and Singh Sahib-Lavish international spread with unlimited premium beverages. Dance to the tunes of DJ Sahil  and listen to live ghazals at Singh Sahib.Empress of China-Exclusive candle light dinner with an elaborate Chinese spread. Lounge and Bar-Unlimited snacks and premium spirits with live band.Price: 3500-4000 per person, When: December 24, 25 and 31, where: Eros Hotel, Nehru PlaceThe Claridges: You can also join in the Christmas and New Year festivities at The Claridges, New Delhi with a variety of options to suit the needs of all. Sevilla at The Claridges, New Delhi is offering a special feast for the upcoming festivities. Inspired by the beautiful, chic city of Seville in Spain, the restaurant is an ode to the colours, style, local ambience and tastes of the uber chic holiday destination. Join in the festivity cheer, with mulled wine and a set menu offering unique dishes from Sevilla. In its new avatar Sevilla has been given not just a new logo, but also a more refined, classical look.When: December 24 Price: INR 4995 + taxes per person Where: The Claridgeslast_img read more

Crime writers on a roll

first_imgFrom violence against women in crime novels to decoding the world of prolific Pakistani crime writer Ibn-e-Safi, the inaugural edition of Crime Writers Festival touches upon an array of issues shaping contemporary crime writing in India.Promoted by Siyahi, a literature promotion group, the two-day festival that began on January 17 and will continue till 18 will be held at the India Habitat Centre.The event is bringing crime and thriller writers from across the world to discuss the art of crime writing to see how it influences society. Touching upon a number of themes the festival pays an ode to this writing genre that is slowly gaining popularity among the masses. Also Read – ‘Playing Jojo was emotionally exhausting’The festival has been conceptualised by Namita Gokhale, co-director of the Jaipur Literature Festival, writer Kishwar Desai and the Crime Writer’s Forum of South Asia. Alka Pande, curator and historian, is donning the hat of creative director.Celebrated authors like Anita Raghavan, Mahmood Farooqui, Ashwin Sanghi, S.Hussain Zaidi and Jerry Pinto, among several others are discussing the world of crime fiction. In a session titled ‘Byomkesh Bakshi and the Bangla Bloodhound’, authors Zac O’ Yeah and Mukul Deva will be drawing distinctions between Indian and Western detective fiction. Along with these discussions, there will also be book-reading sessions and workshops at different venues.last_img read more

Vajpayees ashes immersed at the confluence of Ganga Bay of Bengal

first_imgKolkata: The ashes of former Prime Minister Atal Bihari Vajpayee were today immersed at the confluence of river Ganga and the Bay of Bengal in West Bengal. The ashes were immersed at the confluence of Ganga and the Bay of Bengal after a puja was held in the presence of West Bengal BJP president Dilip Ghosh, Mukul Roy and other senior party leaders at Gangasagar. Gangasagar is an island off the coast of West Bengal where the Ganga meets the Bay of Bengal. Also Read – Rain batters Kolkata, cripples normal life The ‘asthi kalash’ was brought to Kolkata by Ghosh on Wednesday evening. A part of the content from the main ‘kalash’ (urn) has been distributed in four other urns. The main urn will be immersed at Gangasagar and the four others will be taken to north Bengal, Farakka, Bankura and Nabadwip, Jaiprakash Majumdar, vice-president of West Bengal BJP unit told PTI. Yesterday the state BJP unit took out the ‘Asthi Kalash Yatra’ from Kolkata with the ashes of former prime minister Atal Bihari Vajpayee. Also Read – Speeding Jaguar crashes into Mercedes car in Kolkata, 2 pedestrians killed Union minister Smriti Irani had also joined the rally in the morning. Irani said she was overwhelmed at the turnout of people, mostly women, along the roads, to pay respects to the former prime minister. The rally covered various parts of central and south Kolkata and then headed towards Gangasagar. That the people came out in large numbers for the ‘Asthi Kalash Yatra’ only goes on to show how much Vajpayee-ji was loved and revered, said Irani, who was part of the rally till Diamond Harbour. “Tributes were paid to the former PM just the way we pay our respects to elders in our family,” the Union textiles minister said. The BJP central leadership has decided to take out ‘Asthi Kalash Yatras’ in all districts and immerse the ashes in rivers across the country. Processions will start from the state capitals and pass through all blocks, party leaders said.last_img read more

KMC all set for Mayoral poll today

first_imgKolkata: The stage is all set for holding the poll for electing the new Mayor at Kolkata Municipal Corporation (KMC) on Monday. The voting will start at 1 pm sharp and will continue till 2.30 pm. The venue for holding the monthly meeting of the civic body will be the place where four booths have been set up for the polling.It may be mentioned that Firhad Hakim, who holds the post of state Urban Development and Municipal Affairs minister, has been chosen as the Mayor designate by councillors of Trinamool Congress, following Sovan Chatterjee’s resignation from the post. Also Read – Rain batters Kolkata, cripples normal lifeMina Debi Purohit from BJP will contest against Hakim for the Mayoral post, while Left Front and Congress have announced that they will boycott the voting. “We have as many as 122 elected councillors and we are hopeful that all of them will cast their votes in favour of Hakim. So, the wait for him sitting on the chair of the Mayor is just a matter of formality,” a senior KMC councillor said. Hakim is scheduled to attend the swearing-in ceremony, attired in dhoti- panjabi. Deputy Mayor designate Atin Ghosh will also take oath on Monday. Also Read – Speeding Jaguar crashes into Mercedes car in Kolkata, 2 pedestrians killedInterestingly, Hakim on Sunday called up former Mayor Sovan Chatterjee, who is also the councillor of Ward 131 of Trinamool Congress and urged him to be present for the voting on Monday. It may be mentioned that the Calcutta High Court on Friday had refused to stay the election for the Mayoral post in KMC. CPI(M) councillor Bilquis Begum had moved the high court, challenging Hakim’s election on the ground that he was not an elected councillor from any of the wards of the civic body. KMC chairperson Mala Roy held a meeting on Friday with the councillors and urged them all to be present for the voting.last_img read more