WorldWideScience

Sample records for shadow sites photography

  1. Photography.

    Science.gov (United States)

    Oakeley, Henry

    2009-12-01

    A look at 50 years of personal photography, from Brownie Box to Canon digital single-lens reflex cameras, recording life, people, microscope slides and orchids in their habitats and in the studio to digitising old paintings, photos and herbarium specimens. Notes on photographic techniques and the use of ring flash, with comments on long-term conservation of digital images.

  2. In vitro study of the erbium:yttrium aluminum garnet laser cleaning of root canal by the use of shadow photography

    Science.gov (United States)

    Gregorčič, Peter; Lukač, Nejc; Možina, Janez; Jezeršek, Matija

    2016-01-01

    Erbium:yttrium aluminum garnet laser cleaning is a promising technique in endodontic treatment. In our in vitro study, we measured the vapor-bubble dynamics in the root canal by using shadow photography. The canal model was made of a plastic cutout placed between two transparent glass plates. An artificial smear layer was applied to the glass to study cleaning efficiency. In our results, no shock waves have been observed, since the pulp-chamber dimensions have been in the same range as the maximum diameter of the vapor bubble. This leads to the conclusion that shock waves are not the main cleaning mechanism within our model. However, the cleaning effects are also visible in the regions significantly below the bubble. Therefore, it can be concluded that fluid flow induced by the bubble's oscillations contributes significantly to the canal cleaning. We also proposed a simple theoretical model for cleaning efficiency and used it to evaluate the measured data.

  3. Does underwater flash photography affect the behaviour, movement and site persistence of seahorses?

    Science.gov (United States)

    Harasti, D; Gladstone, W

    2013-11-01

    The effect of flash photography on seahorse species has never been tested. An experiment was established to test the effect of flash photography and the handling of Hippocampus whitei, a medium-sized seahorse species endemic to Australia, on their behavioural responses, movements and site persistence. A total of 24 H. whitei were utilized in the experiment with eight in each of the three treatments (flash photography, handling and control). The effect of underwater flash photography on H. whitei movements was not significant; however, the effect of handling H. whitei to take a photograph had a significant effect on their short-term behavioural responses to the photographer. Kaplan-Meier log-rank test revealed that there was no significant difference in site persistence of H. whitei from each of the three treatments and that flash photography had no long-term effects on their site persistence. It is concluded that the use of flash photography by divers is a safe and viable technique with H. whitei, particularly if photographs can be used for individual identification purposes. © 2013 The Fisheries Society of the British Isles.

  4. The identification of archaeological sites by false color infrared aerial photography

    Science.gov (United States)

    Gumerman, G. J.

    1971-01-01

    The study of color infrared photography of Tehuacan Valley, Mexico was made to determine the applicability of remotely sensed data to archeology. Photography was interpreted without prior knowledge of the area, followed by a field check to determine accuracy of the original interpretations and to evaluate causes of successes and failures. Results indicate that the visibility of sites depends primarily on its environmental situation, and also that the delineation of environments and microenvironments is especially easy with this type of film. Furthermore, the age and size of the sites are not necessarily the deciding factors in their discernment.

  5. Shadow art

    KAUST Repository

    Mitra, Niloy J.

    2009-01-01

    "To them, I said, the truth would be literally nothing but the shadows of the images." - Plato, The Republic Shadow art is a unique form of sculptural art where the 2D shadows cast by a 3D sculpture are essential for the artistic effect. We introduce computational tools for the creation of shadow art and propose a design process where the user can directly specify the desired shadows by providing a set of binary images and corresponding projection information. Since multiple shadow images often contradict each other, we present a geometric optimization that computes a 3D shadow volume whose shadows best approximate the provided input images. Our analysis shows that this optimization is essential for obtaining physically realizable 3D sculptures. The resulting shadow volume can then be modified with a set of interactive editing tools that automatically respect the often intricate shadow constraints. We demonstrate the potential of our system with a number of complex 3D shadow art sculptures that go beyond what is seen in contemporary art pieces. © 2009 ACM.

  6. Neptune shadows

    Science.gov (United States)

    1999-01-01

    This image of Neptune shows the discovery of shadows in Neptune's atmosphere, shadows cast onto a deep cloud band by small elevated clouds. They are the first cloud shadows ever seen by Voyager on any planet. Estimates of the height of these discrete clouds above the underlying cloud bank can be obtained by careful analysis of this data. The Voyager Mission is conducted by JPL for NASA'S Office of Space Science and Applications.

  7. Facilitating the Development and Evaluation of a Citizen Science Web Site: A Case Study of Repeat Photography and Climate Change in Southwest Alaska's National Parks

    Science.gov (United States)

    Mullen, Karina C.; Newman, Gregory; Thompson, Jessica L.

    2013-01-01

    Interviews with national park visitors across the country revealed that climate change education through place-based, hands-on learning using repeat photographs and technology is appealing to park visitors. This manuscript provides a summary of the development of a repeat photography citizen science Web site for national parks in Southwest Alaska.…

  8. Mars Hand Lens Imager (MAHLI) Efforts and Observations at the Rocknest Eolian Sand Shadow in Curiosity's Gale Crater Field Site

    Science.gov (United States)

    Edgett, K. S.; Yingst, R. A.; Minitti, M. E.; Goetz, W.; Kah, L. C.; Kennedy, M. R.; Lipkaman, L. J.; Jensen, E. H.; Anderson, R. C.; Beegle, L. W.; hide

    2013-01-01

    The Mars Science Laboratory (MSL) mission is focused on assessing the past or present habitability of Mars, through interrogation of environment and environmental records at the Curiosity rover field site in Gale crater. The MSL team has two methods available to collect, process and deliver samples to onboard analytical laboratories, the Chemistry and Mineralogy instrument (CheMin) and the Sample Analysis at Mars (SAM) instrument suite. One approach obtains samples by drilling into a rock, the other uses a scoop to collect loose regolith fines. Scooping was planned to be first method performed on Mars because materials could be readily scooped multiple times and used to remove any remaining, minute terrestrial contaminants from the sample processing system, the Collection and Handling for In-Situ Martian Rock Analysis (CHIMRA). Because of this cleaning effort, the ideal first material to be scooped would consist of fine to very fine sand, like the interior of the Serpent Dune studied by the Mars Exploration Rover (MER) Spirit team in 2004 [1]. The MSL team selected a linear eolian deposit in the lee of a group of cobbles they named Rocknest (Fig. 1) as likely to be similar to Serpent Dune. Following the definitions in Chapter 13 of Bagnold [2], the deposit is termed a sand shadow. The scooping campaign occurred over approximately 6 weeks in October and November 2012. To support these activities, the Mars Hand Lens Imager (MAHLI) acquired images for engineering support/assessment and scientific inquiry.

  9. Resolution Of A Shadow Image

    Science.gov (United States)

    Edgerton, Harold E.

    1982-02-01

    The 19th century art of shadow imaging, as started by Wedgwood (1803), and as used by William Henry Fox-Talbot (1851) in England, has been revived by using a small-area electronic flash lamp and fine grain film. One immediate application has been the photographic recording of large samples of living plankton. The purpose of this paper is to re-examine the resolution of the shadow system, and to describe some of the strobe light sources that are presently available. Also, a modified method of shadow photography is described where enhanced color images give interesting and, perhaps, important color effects that may be useful in the study of plankton and other semitrans-parent subjects.

  10. Photography Reframed

    OpenAIRE

    Anna Dahlgren

    2016-01-01

    This article discusses the benefits of analysing photography as mediated, repro-duced and entangled in media systems, and consequently as part of a larger media culture. Moreover it combines technological considerations drawn from media ar-chaeology with art historical analysis focusing on visual aesthetics. It considers two mediating devices for photography in the nineteenth century, the photo album and the illustrated press. As displayed, a media historical perspective airs new interpre-tat...

  11. Shadow of sound

    OpenAIRE

    Prvacki, Ana

    2017-01-01

    Tiré du site Internet de Onestar Press: "Shadow of sound is a musical flip book, an attempt to move sound through pages and to measure music visually. Prvacki demonstrates that 40 seconds of Bach's Minuet in G Major fit on 150 pages.".

  12. Diagnosing Surgical Site Infection Using Wound Photography: A Scenario-Based Study.

    Science.gov (United States)

    Sanger, Patrick C; Simianu, Vlad V; Gaskill, Cameron E; Armstrong, Cheryl A L; Hartzler, Andrea L; Lordon, Ross J; Lober, William B; Evans, Heather L

    2017-01-01

    Postoperative surgical site infections (SSI) are common and costly. Most occur post discharge, and can result in potentially preventable readmission or unnecessary urgent evaluation. Mobile health approaches incorporating patient-generated wound photos are being implemented in an attempt to optimize triage and management. We assessed how adding wound photos to existing data sources modifies provider decision making. We used a web-based simulation survey using a convenience sample of providers with expertise in surgical infections. Participants viewed a range of scenarios, including surgical history, physical exam, and description of wound appearance. All participants reported SSI diagnosis, diagnostic confidence, and management recommendations (main outcomes) first without, and then with, accompanying wound photos. At each step, participants ranked the most important features contributing to their decision. Eighty-three participants completed a median of 5 scenarios (interquartile range 4 to 7). Most participants were physicians in academic surgical specialties (n = 70 [84%]). The addition of photos improved overall diagnostic accuracy from 67% to 76% (p < 0.001), and increased specificity from 77% to 92% (p < 0.001), but did not significantly increase sensitivity (55% to 65%; p = 0.16). Photos increased mean confidence in diagnosis from 5.9 of 10 to 7.4 of 10 (p < 0.001). Overtreatment recommendations decreased from 48% to 16% (p < 0.001), and undertreatment did not change (28% to 23%; p = 0.20) with the addition of photos. The addition of wound photos to existing data as available via chart review and telephone consultation with patients significantly improved diagnostic accuracy and confidence, and prevented proposed overtreatment in scenarios without SSI. Post-discharge mobile health technologies have the potential to facilitate patient-centered care, decrease costs, and improve clinical outcomes. Copyright © 2016 American College of Surgeons. Published by

  13. Literature & Photography.

    Science.gov (United States)

    Plattor, Emma E.

    An effective way to teach literature to students accustomed to electronic media is to use prose and poetry as raw materials for the production of photography projects that translate print into more familiar and exciting forms. Studies confirm that "visual literacy" should be an important part of a modern student's education. "Picture reading," an…

  14. Shadow Soldiering

    DEFF Research Database (Denmark)

    Mynster Christensen, Maya

    The thesis is an inquiry into what is at stake for a surplus population of militia soldiers in the aftermaths of the civil war in Sierra Leone. The analysis takes its point of departure in how militarised networks are transformed and gradualy morph into new constellations of soldiering. The central...... question the thesis pursues is how the processes of mobilisation connecting these constellations are facilitated, and how the constellations are constituted in the intersection between local and global formations. Shadow soldiering, it is argued, is not a phenomenon existing in parallel with...

  15. Influence of shadow removal on image classification in riverine environments.

    Science.gov (United States)

    Filippi, Anthony M; Güneralp, İnci

    2013-05-15

    Shadows in remote-sensor images can yield marked errors in classification of riverine environments. We propose use of a modified shadow-removal algorithm as a preprocessing step for remote-sensing image classification of riverine landscapes. To accommodate characterization of spatially complex river features in the image, we investigate an illumination suppression-based shadow-removal algorithm, modified to include a user-defined tiling approach. We quantitatively evaluate the influence of shadow removal from aerial photography on classification accuracy as such studies are currently lacking. Experimental results demonstrate that this modified shadow-removal method significantly increases classification accuracy and improves detection of small river channels partially obscured by shadow.

  16. The power of shadows - Shadow stereopsis

    Science.gov (United States)

    Puerta, Antonio Medina

    1989-01-01

    It is demonstrated that retinal images with no parallax disparity but with different shadows are fused stereoscopically, imparting depth perception to the imaged scene. Shadows are shown to be an important, hitherto undescribed, stereoscopic cue for depth perception.

  17. Photography applications

    Science.gov (United States)

    Cochran, Susan A.; Goodman, James A.; Purkis, Samuel J.; Phinn, Stuart R.

    2013-01-01

    Photographic imaging is the oldest form of remote sensing used in coral reef studies. This chapter briefly explores the history of photography from the 1850s to the present, and delves into its application for coral reef research. The investigation focuses on both photographs collected from low-altitude fixed-wing and rotary aircraft, and those collected from space by astronauts. Different types of classification and analysis techniques are discussed, and several case studies are presented as examples of the broad use of photographs as a tool in coral reef research.

  18. Digital food photography

    National Research Council Canada - National Science Library

    Manna, Lou; Moss, Bill

    2005-01-01

    ... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 2 Digital Photography: The Necessities 21 Selecting a Digital Camera and Accessories...

  19. Mobile Media Photography

    DEFF Research Database (Denmark)

    Svabo, Connie; Shanks, Michael

    2013-01-01

    Mobile media photography marks a shift in orientation from the image towards photography as a mode of engagement. This leads is to explore the processes of experience and documentation that mobile media help to constitute. We unfold two aspects of the process of photography: photography as temporal...

  20. The life valley of the shadow: reflections on war photography and its repercussions O vale da sombra da vida: reflexões sobre a fotografia de guerra e suas repercussões

    Directory of Open Access Journals (Sweden)

    Paulo Cesar Boni

    2006-12-01

    Full Text Available Reflections on war photography and its repercussions in society and in the socialization capacity of those who produce it are the aim of this paper. On a starting point of view, the war photographer is as professional as anyone else; however, constant exposure to danger and the eminence of death affect his relationship within society. This article stresses critically the path of war photojournalism and seeks to encourage reflection on the – and about the – three agents of the communication process: the producer, the conveyor, and the recipient. Reflexões sobre a fotografia de guerra e suas repercussões na sociedade e na capacidade de socialização de quem a produz são as propostas norteadoras deste trabalho. Num primeiro momento, o fotógrafo de guerra é um profissional como outro qualquer, mas a constante exposição ao perigo e a eminência da morte afetam sua convivência em sociedade. O artigo resgata criticamente a trajetória do fotojornalismo de guerra e busca instigar a reflexão nos – e sobre os – três agentes do processo de comunicação: o produtor, o transmissor e o receptor.

  1. Surprising Beauty in Technical Photography

    Science.gov (United States)

    Davidhazy, Andrew

    2009-01-01

    The Imaging and Photographic Technology area, in which the author teaches, is an applications- and technology-oriented photography program designed to prepare students for work in technical, corporate, industrial, and scientific environments. One day, the author received an e-mail message from an editor who had found his Web site and thought he…

  2. Nordic (Art) Photography

    DEFF Research Database (Denmark)

    Sandbye, Mette

    2013-01-01

    A description of the rise of the role of photography on the Scandinavian art scene the last 25 years......A description of the rise of the role of photography on the Scandinavian art scene the last 25 years...

  3. Real-time shadows

    CERN Document Server

    Eisemann, Elmar; Assarsson, Ulf; Wimmer, Michael

    2011-01-01

    Important elements of games, movies, and other computer-generated content, shadows are crucial for enhancing realism and providing important visual cues. In recent years, there have been notable improvements in visual quality and speed, making high-quality realistic real-time shadows a reachable goal. Real-Time Shadows is a comprehensive guide to the theory and practice of real-time shadow techniques. It covers a large variety of different effects, including hard, soft, volumetric, and semi-transparent shadows.The book explains the basics as well as many advanced aspects related to the domain

  4. Shadow algorithms data miner

    CERN Document Server

    Woo, Andrew

    2012-01-01

    Digital shadow generation continues to be an important aspect of visualization and visual effects in film, games, simulations, and scientific applications. This resource offers a thorough picture of the motivations, complexities, and categorized algorithms available to generate digital shadows. From general fundamentals to specific applications, it addresses shadow algorithms and how to manage huge data sets from a shadow perspective. The book also examines the use of shadow algorithms in industrial applications, in terms of what algorithms are used and what software is applicable.

  5. Sociology through Photography

    Science.gov (United States)

    Hyde, Katherine

    2015-01-01

    This chapter describes how photography can inspire and cultivate sociological mindfulness. One set of assignments uses self-portraiture to highlight the complexity of visual representations of social identity. Another uses photography to guide sociological inquiry. Both sets of assignments draw on the Literacy Through Photography methodology,…

  6. Shadowing and hyperbolicity

    CERN Document Server

    Pilyugin, Sergei Yu

    2017-01-01

    Focusing on the theory of shadowing of approximate trajectories (pseudotrajectories) of dynamical systems, this book surveys recent progress in establishing relations between shadowing and such basic notions from the classical theory of structural stability as hyperbolicity and transversality. Special attention is given to the study of "quantitative" shadowing properties, such as Lipschitz shadowing (it is shown that this property is equivalent to structural stability both for diffeomorphisms and smooth flows), and to the passage to robust shadowing (which is also equivalent to structural stability in the case of diffeomorphisms, while the situation becomes more complicated in the case of flows). Relations between the shadowing property of diffeomorphisms on their chain transitive sets and the hyperbolicity of such sets are also described. The book will allow young researchers in the field of dynamical systems to gain a better understanding of new ideas in the global qualitative theory. It will also be of int...

  7. The future of photography

    Science.gov (United States)

    Motta, Ricardo J.

    2010-01-01

    We are just a few years away from celebrating the 200th anniversary of photography. The first permanent photographic record was made by Niepce in 1826, the view from his window at Le Gras. After many development cycles, including some periods of stagnation, photography is now experience an amazing period of growth. Change since the mid 90's going into the next several years will completely modify photography and its industry. We propose that the digital photography revolution can be divided into two phases. The first, from about 1994 to 2009, was primarily the transformation of film-based equipment into their digital counterparts. Now, in the second phase, photography is starting to change into something completely different, with forces like social networks, cell phone cameras and computational photography changing the business, the methods and the use of photographs.

  8. Shadows behind the computers

    CERN Multimedia

    CERN audiovisual service; Jacques Fichet

    2007-01-01

    EGEE organized a shadowing day to spur female students to take up careers in the IT field. Eleven female staff from CERN’s IT Department were kept under close surveillance last week, shadowed by female students from the Collège du Léman International School as part of the Enabling Grids for E-sciencE project Gender Action Plan.

  9. Art in Portrait Photography.

    Science.gov (United States)

    Hubbard, Guy

    1999-01-01

    Explains that the best way for students to learn to recognize high-quality portrait photography is to study as many good examples as possible. Provides examples of portrait photography by David Hockney, Dorothea Lange, Edward Steichen, and Thomas M. Easterly in order to demonstrate different portrait styles and techniques and to promote…

  10. Metaphors in Photography Language

    Directory of Open Access Journals (Sweden)

    Iryna Mykytka

    2016-11-01

    Full Text Available Metaphors have been the focus of many studies that embrace a wide range of aspects and diverse fields of knowledge given the colossal diversity of work now being undertaken (Lakoff & Johnson, 1980; Lakoff, 1987, 1993; Ortony, 1993; Kövecses, 1990, 2003, 2005, 2010; Gibbs, 2008; Forceville & Urios-Aparisi, 2009. They are no longer restricted to literature or poetry as an ornamental device, but they are present in everyday language including the technical fields. Numerous studies have been carried out on metaphor in different specialized discourses. However, little attention has been paid to the photography genre so far. The present paper, thus, focuses mainly on the use of verbal metaphor in the language of photography as one of many fields of English for Specific Purposes (ESP. The aim of this research is to investigate metaphors used to construct photographic concepts in the photography blogs which constitute the data of this study. The Metaphor Identification Procedure (MIP developed by the Pragglejaz Group (2007 has been used to identify metaphoric expression. The analysis of these metaphoric expressions was based on Conceptual Metaphor Theory (Lakoff & Johnson, 1980. The data analysis indicates that there is a great variety of conceptual metaphors present in photography blogs, projected through conceptual mapping from different source domains into the target domain, such as PHOTOGRAPHY IS A WAR, PHOTOGRAPHY IS HUNTING, PHOTOGRAPHY IS A GAME, A CAMERA IS A GUN, A CAMERA IS A PERSON, among others.

  11. Encountering Over/sights. Remembering Invisible Pasts through Photography

    DEFF Research Database (Denmark)

    Wiegand, Frauke Katharina

    2014-01-01

    . Discussing different forms of cultural memorialisation in South Africa, a special focus is put on visual cultural memory, photography, the notion of absence and visibility. While the tourist script here seems to require a tangible memorial and proper 'sites' to visit, contemporary South African photography...

  12. Involvement through photography.

    Science.gov (United States)

    Takai, J

    2016-12-01

    As a photographer living in Tokyo, I have been visiting Suetsugi village regularly to take photographs and show the printed photographs to the residents. What is the role of photography? What does it mean to be involved in the life of Suetsugi through photography? This article discusses some of the answers to these questions 5 years after the accident at Fukushima Daiichi nuclear power plant.

  13. Monitoring plant phenology using digital repeat photography.

    Science.gov (United States)

    Crimmins, Michael A; Crimmins, Theresa M

    2008-06-01

    Repeated observations of plant phenology have been shown to be important indicators of global change. However, capturing the exact date of key events requires daily observations during the growing season, making phenologic observations relatively labor intensive and costly to collect. One alternative to daily observations for capturing the dates of key phenologic events is repeat photography. In this study, we explored the utility of repeat digital photography for monitoring phenologic events in plants. We provide an illustration of this approach and its utility by placing observations made using repeat digital imagery in context with local meteorologic and edaphic variables. We found that repeat photography provides a reliable, consistent measurement of phenophase. In addition, digital photography offers advantages in that it can be mathematically manipulated to detect and enhance patterns; it can classify objects; and digital photographs can be archived for future analysis. In this study, an estimate of greenness and counts of individual flowers were extracted by way of mathematic algorithms from the photo time series. These metrics were interpreted using meteorologic measurements collected at the study site. We conclude that repeat photography, coupled with site-specific meteorologic measurements, could greatly enhance our understanding environmental triggers of phenologic events. In addition, the methods described could easily be adopted by citizen scientists and the general public as well as professionals in the field.

  14. Technological updates in dental photography.

    Science.gov (United States)

    Shagam, Josh; Kleiman, Alan

    2011-07-01

    Digital photography is a constantly evolving medium that can be used in dentistry for a number of applications including documentation and patient education. In the past 5 years, it has become standard professional practice for photographers to shoot in raw format, organize and edit in Adobe Photoshop Lightroom, and archive files using portable hard drives and off-site storage. Concurrently, cameras have increased resolution, improved antidust technology, and added versatile flash accessories for macro imaging. Adopting professional photographic practices and taking advantage of technological developments in a dental practice can be an invaluable tool in education and documentation. Copyright © 2011 Elsevier Inc. All rights reserved.

  15. Reusable High Aspect Ratio 3-D Nickel Shadow Mask.

    Science.gov (United States)

    Shandhi, M M H; Leber, M; Hogan, A; Warren, D J; Bhandari, R; Negi, S

    2017-04-01

    Shadow Mask technology has been used over the years for resistless patterning and to pattern on unconventional surfaces, fragile substrate and biomaterial. In this work, we are presenting a novel method to fabricate high aspect ratio (15:1) three-dimensional (3D) Nickel (Ni) shadow mask with vertical pattern length and width of 1.2 mm and 40 μm respectively. The Ni shadow mask is 1.5 mm tall and 100 μm wide at the base. The aspect ratio of the shadow mask is 15. Ni shadow mask is mechanically robust and hence easy to handle. It is also reusable and used to pattern the sidewalls of unconventional and complex 3D geometries such as microneedles or neural electrodes (such as the Utah array). The standard Utah array has 100 active sites at the tip of the shaft. Using the proposed high aspect ratio Ni shadow mask, the Utah array can accommodate 300 active sites, 200 of which will be along and around the shaft. The robust Ni shadow mask is fabricated using laser patterning and electroplating techniques. The use of Ni 3D shadow mask will lower the fabrication cost, complexity and time for patterning out-of-plane structures.

  16. Shadows behind the computers

    CERN Multimedia

    2007-01-01

    EGEE organized a shadowing day to spur female students to take up careers in the IT field. Eleven female staff from CERN’s IT Department were kept under close surveillance last week, shadowed by female students from the Collège du Léman International School as part of the Enabling Grids for E-sciencE project Gender Action Plan. The shadowing day was aimed at inspiring young women to think of careers in information technology, by passing on the message that careers in science are open to both men and women and can be rewarding and fun. The students were given a tour of the ATLAS physics experiment and the CERN Computer Centre, as well as the opportunity for one-to-one interaction with CERN IT staff. Traditionally, fewer women work in the IT sector; women currently represent 21% of EGEE staff. The shadowing day was held as part of the EGEE Gender Action Plan, reflecting a commitment to reducing this gender gap. Other initiatives in...

  17. [Photography in medical research].

    Science.gov (United States)

    Hochman, Bernardo; Nahas, Fabio Xerfan; Ferreira, Lydia Masako

    2005-01-01

    Medical photography is an adequate scientific document when performed on a standard fashion. A proper photography is an important issue on a scientific publication. Plastic surgeons are experts in clinical photography and, frequently, an image is a more significant data than the written part of a paper. The purpose of this article is to describe the principles developed in this specialty. Basic photographic equipment used for clinical pictures is described. Standardized pictures determined by patient position and framing using anatomical references are reported. Using these rules it is possible to compare pre and post operative pictures. Topics such as intra operative pictures in endoscopic surgery, computer fotogrametry and in Experimental Surgery are also analyzed.

  18. Travel Photography: Destination Workshop

    OpenAIRE

    Pradhan, Mukul

    2016-01-01

    Travel photography is a growing and highly popular form of tourism in most parts of the world but despite huge potentials, certain places in the world have yet to capitalize on this opportunity. Among these destinations, Nepal, a country filled with breath-taking landscape and ever-vibrant and growing urban cities has done little to provide this experience of trav-el photography to travelers. Hence, the goal of this Bachelor’s thesis was to develop an at-tractive, affordable and unforgettable...

  19. System for creative photography

    OpenAIRE

    Vesel, Jan

    2011-01-01

    The aim of the thesis was to make a photographic accessory or system that can expand the ability of creative photography. It allows the photographer to use an extreme exposure at which the camera can record high-speed photos and interval photos (e.g., water balloon pop, water drop splash or bullet hitting grape berry). The thesis presents a system for creative photography that consists of: an Arduino microcontroller, a GPS module, a control circuitry, sensors, an Android device and its sof...

  20. Dreams Memories & Photography

    Science.gov (United States)

    Young, Bernard

    2012-01-01

    Photography students spend a considerable amount of time working on technical issues in shooting, composing, editing, and processing prints. Another aspect of their learning should include the conception and communication of their ideas. A student's memories and dreams can serve as motivation to create images in visual art. Some artists claim that…

  1. Exploring Racism through Photography

    Science.gov (United States)

    Fey, Cass; Shin, Ryan; Cinquemani, Shana; Marino, Catherine

    2010-01-01

    Photography is a powerful medium with which to explore social issues and concerns through the intersection of artistic form and concept. Through the discussions of images and suggested activities, students will understand various ways photographers have documented and addressed racism and discrimination. This Instructional Resource presents a…

  2. What Colour Is a Shadow?

    Science.gov (United States)

    Hughes, S. W.

    2009-01-01

    What colour is a shadow? Black, grey, or some other colour? This article describes how to use a digital camera to test the hypothesis that a shadow under a clear blue sky has a blue tint. A white sheet of A4 paper was photographed in full sunlight and in shadow under a clear blue sky. The images were analysed using a shareware program called…

  3. Smartphone Fundus Photography.

    Science.gov (United States)

    Nazari Khanamiri, Hossein; Nakatsuka, Austin; El-Annan, Jaafar

    2017-07-06

    Smartphone fundus photography is a simple technique to obtain ocular fundus pictures using a smartphone camera and a conventional handheld indirect ophthalmoscopy lens. This technique is indispensable when picture documentation of optic nerve, retina, and retinal vessels is necessary but a fundus camera is not available. The main advantage of this technique is the widespread availability of smartphones that allows documentation of macula and optic nerve changes in many settings that was not previously possible. Following the well-defined steps detailed here, such as proper alignment of the phone camera, handheld lens, and the patient's pupil, is the key for obtaining a clear retina picture with no interfering light reflections and aberrations. In this paper, the optical principles of indirect ophthalmoscopy and fundus photography will be reviewed first. Then, the step-by-step method to record a good quality retinal image using a smartphone will be explained.

  4. Is shadow banking really banking?

    OpenAIRE

    Bryan J. Noeth; Rajdeep Sengupta

    2011-01-01

    To those who don't know, the term "shadow banking" probably has a negative connotation. This primer draws parallels between what has been termed the shadow banking sector and the traditional banking sector—showing that they are similar in many ways.

  5. Photography: daguerreotype and the African experience | Nwafor ...

    African Journals Online (AJOL)

    ... assumptions in colonial stereotypical photography especially as they affect Africa. While colonial stereotypical photography persisted, Africans attempted to forge a ... undertakes a critique of documentary photography and visuality in gender.

  6. UV Photography Shows Hidden Sun Damage

    Science.gov (United States)

    ... mcat1=de12", ]; for (var c = 0; c UV photography shows hidden sun damage A UV photograph gives ... developing skin cancer and prematurely aged skin. Normal photography UV photography 18 months of age: This boy's ...

  7. Photography with a Microscope

    Science.gov (United States)

    Rost, Fred; Oldfield, Ron

    2000-03-01

    This beautifully illustrated book describes the methods used to record images viewed through a microscope. The text describes the principles and practices of photomicrography, and is written for all who take photomicrographs, beginners and/or experienced practitioners. The authors describe techniques that may be applied to many disciplines for teaching, research, archives, or pleasure. The book includes chapters on standard photography, modern digital techniques, methods for improving contrast, and a short chapter on drawing. In addition to its value as a work of reference, the authors' clear, didactic style makes this book suitable as a textbook for courses in photomicrography and/or elementary light microscopy.

  8. AN ASSESSMENT OF SHADOW ENHANCED URBAN REMOTE SENSING IMAGERY OF A COMPLEX CITY – HONG KONG

    Directory of Open Access Journals (Sweden)

    C.-Y. Wan

    2012-07-01

    Full Text Available Large portions of shadowed areas in satellite images of urban areas can affect the accuracy of classification and thus reduce an image's effectiveness in urban remote sensing applications. This is particularly acute in cities such as Hong Kong where dense high-rise buildings cast many long shadows across a variety of different surface types. One solution to this problem is to enhance shadowed areas so their spectral range becomes closer to their corresponding non-shadowed areas. Shadowed areas were automatically selected and two techniques, Gamma correction and Linear Correlation Correction, were applied to three study sites of a 2.4 m Quickbird image. The selected study sites represent typical urban types of Hong Kong, ranging from high-rise commercial to low-rise residential areas. The shadow detection algorithm is based on the spectral shape index and its limitation is discussed. The histograms of the corresponding non-shadowed areas, the original and the enhanced shadow areas are used to compare the spectral range. The results show that the enhanced areas, in band ratios such as NDVI, show greater similarity after enhancement, but they also look darker than the non-shadowed areas. Where continuous shadowed areas such as in commercial areas, the spectral range cannot be restored.

  9. Digital clinical photography: practical tips.

    Science.gov (United States)

    Mutalik, Sharad

    2010-01-01

    Photographs are the most preferred and easiest way of documentation of patient visual features. In aesthetic and cutaneous surgery, there is an increased need for proper photographic documentation, from a medicolegal view point. This article discusses the basic aspects of camera and photography which a dermatologist should be aware before he/she starts with clinical photography.

  10. Digital clinical photography: Practical tips

    Directory of Open Access Journals (Sweden)

    Sharad Mutalik

    2010-01-01

    Full Text Available Photographs are the most preferred and easiest way of documentation of patient visual features. In aesthetic and cutaneous surgery, there is an increased need for proper photographic documentation, from a medicolegal view point. This article discusses the basic aspects of camera and photography which a dermatologist should be aware before he/she starts with clinical photography.

  11. Digital Clinical Photography: Practical Tips

    OpenAIRE

    Sharad Mutalik

    2010-01-01

    Photographs are the most preferred and easiest way of documentation of patient visual features. In aesthetic and cutaneous surgery, there is an increased need for proper photographic documentation, from a medicolegal view point. This article discusses the basic aspects of camera and photography which a dermatologist should be aware before he/she starts with clinical photography.

  12. How to See Shadows in 3D

    Science.gov (United States)

    Parikesit, Gea O. F.

    2014-01-01

    Shadows can be found easily everywhere around us, so that we rarely find it interesting to reflect on how they work. In order to raise curiosity among students on the optics of shadows, we can display the shadows in 3D, particularly using a stereoscopic set-up. In this paper we describe the optics of stereoscopic shadows using simple schematic…

  13. Out of shadow / Peeter Linnap

    Index Scriptorium Estoniae

    Linnap, Peeter, 1960-

    2007-01-01

    "Out of shadow" oli näitus Baltimaade 1990. aastate kunstist Ameerika publikule - sõnumiks iseseisvumisjärgsete aastate materiaalse, sotsiaalse ning vaimuelu peegeldused/tõlgendused visuaalses kunstis

  14. Digital Photography and Cinema

    Directory of Open Access Journals (Sweden)

    Alberto Sdegno

    2013-10-01

    Full Text Available In some significant film productions of the last thirty years photography play an innovative role, not only from a technical point of view, but also regarding the plot of the movie. The examples described in the text - from Blade Runner to the recent Inception - may allow a better understanding of the way in which the technology of image processing has altered the perception of film sequences, also helping to transform the opinions on this new way of work by artists usually adopting traditional practices, such as Wim Wenders. His film, Until the end of the world, in fact, appears as an episode particularly eloquent in the filmography of the artist, which testifies a change in the definition of the working method.

  15. Mars Cameras Make Panoramic Photography a Snap

    Science.gov (United States)

    2008-01-01

    If you wish to explore a Martian landscape without leaving your armchair, a few simple clicks around the NASA Web site will lead you to panoramic photographs taken from the Mars Exploration Rovers, Spirit and Opportunity. Many of the technologies that enable this spectacular Mars photography have also inspired advancements in photography here on Earth, including the panoramic camera (Pancam) and its housing assembly, designed by the Jet Propulsion Laboratory and Cornell University for the Mars missions. Mounted atop each rover, the Pancam mast assembly (PMA) can tilt a full 180 degrees and swivel 360 degrees, allowing for a complete, highly detailed view of the Martian landscape. The rover Pancams take small, 1 megapixel (1 million pixel) digital photographs, which are stitched together into large panoramas that sometimes measure 4 by 24 megapixels. The Pancam software performs some image correction and stitching after the photographs are transmitted back to Earth. Different lens filters and a spectrometer also assist scientists in their analyses of infrared radiation from the objects in the photographs. These photographs from Mars spurred developers to begin thinking in terms of larger and higher quality images: super-sized digital pictures, or gigapixels, which are images composed of 1 billion or more pixels. Gigapixel images are more than 200 times the size captured by today s standard 4 megapixel digital camera. Although originally created for the Mars missions, the detail provided by these large photographs allows for many purposes, not all of which are limited to extraterrestrial photography.

  16. Mick Gidley, Photography and the USA.

    Directory of Open Access Journals (Sweden)

    Theodora Tsimpouki

    2011-09-01

    Full Text Available Mick Gidley’s Photography and the USA is premised on the conviction that there is “a symbiotic connection” between the medium of photography and the American nation, especially in the aftermath of the Second World War. Given that Photography and the USA belongs to a series of books under the general title Exposures designed to explore photography from thematic perspectives or in relation to significant nationalities (i.e. “photography and literature,” “photography and cinema,” “photography an...

  17. SHADOW: a new welding technique

    Science.gov (United States)

    Kramer, Thorsten; Olowinsky, Alexander M.; Durand, Friedrich

    2002-06-01

    The new welding technique 'SHADOW ' is introduced. SHADOW means the use of a single pulse to generate a quasi continuous weld of several millimeters in length. HET processing time is defined by the pulse duration of the pulsed laser. At present, a state-of-the-art laser is capable of a maximum pulse duration of 20 ms. The variation of the laser power depend on time is a vital capability of the pulsed laser to adapt the energy deposition into the workpiece. Laser beam welds of several watch components were successfully performed. Similar metals like crowns and axes made out of stainless steel have been welded using pulsed laser radiation. Applying a series of about 130 single pulses for the crown-axis combination the total energy accumulates to 19.5 J. The use of the SHADOW welding technique reduces the energy to 2.5 J. While welding dissimilar metals like stainless steel and bras, the SHADOW welding reduces drastically the contamination as well as the distortion. Laser beam welding of copper has a low process reliability due to the high reflection and the high thermal conductivity. SHADOW welds of 3.6 mm length were performed on 250 micrometers thick copper plates with very high reproducibility. As a result, a pilot plant for laser beam welding of copper plates has been set up. The work to be presented has partly been funded by the European Commission in a project under the contract BRPR-CT-0634.

  18. Doctoring Undercover: updating the educational tradition of shadowing.

    Science.gov (United States)

    Clark, Claire D

    2017-01-01

    Premedical students are educated in basic biological and health sciences. As a complement to traditional premedical coursework, medical school applicants are encouraged to shadow practitioners, with the hope that observation will introduce students to the culture and practice of healthcare. Yet the shadowing experience varies widely across practitioners and institutions; resources that guide students' critical reflection and structure the experience are scarce. A pilot experiential learning course, Doctoring Undercover: Shadowing and the Culture of Medicine, was developed to fill this gap. The course consisted of three parts: an introduction to medical culture through the disciplines of medical sociology, history, anthropology, and bioethics; a site placement in which students applied these fields' analytical techniques to the study of medical culture and practice; and the development of an online activity guide that other premedical students may adapt to their shadowing circumstances. Students reported that they were exposed to new disciplinary perspectives and interprofessional environments that they would not traditionally encounter. Students' contributions to the shadowing guide encouraged active learning and reflection on the dynamics of effective patient-provider relationships and shadowing experiences. Locally, the class may be scaled for a larger group of premedical students and incorporated into a formal pathway program for premedical students; the content will also be integrated into the clinical medicine course for first-year medical students. Online, the guide will be promoted for use by other institutions and by individuals planning extracurricular shadowing experiences; feedback will be solicited. Tools for evaluating the short- and long-term impact of the course and guide will be developed and validated. Observational and experimental studies of the course's impact should be conducted. ICM: Introduction to Clinical Medicine; SCE: Selective Clinical

  19. A Look at Children's Conception of Shadows.

    Science.gov (United States)

    Sia, Archibald Peterson C.

    1980-01-01

    Describes a study designed to compare the gradual development of children's understanding of shadows with Piaget's stages, categorize pupil responses in the shadow tasks, identify typical pupil responses in each category, and enumerate curriculum implications from the investigation. (GS)

  20. Editing soft shadows in a digital photograph.

    Science.gov (United States)

    Mohan, Ankit; Tumblin, Jack; Choudhury, Prasun

    2007-01-01

    This technique for modeling, editing, and rendering shadow edges in a photograph or a synthetic image lets users separate the shadow from the rest of the image and make arbitrary adjustments to its position, sharpness, and intensity.

  1. Detection and Removal of Chromatic Moving Shadows in Surveillance Scenarios

    DEFF Research Database (Denmark)

    Casado, Ivan Huerta; Holte, Michael Boelstoft; Moeslund, Thomas B.

    2009-01-01

      Segmentation in the surveillance domain has to deal with shadows to avoid distortions when detecting moving objects. Most segmentation approaches dealing with shadow detection are typically restricted to penumbra shadows. Therefore, such techniques cannot cope well with umbra shadows. Consequen......  Segmentation in the surveillance domain has to deal with shadows to avoid distortions when detecting moving objects. Most segmentation approaches dealing with shadow detection are typically restricted to penumbra shadows. Therefore, such techniques cannot cope well with umbra shadows...

  2. Study on Processing Method of Image Shadow

    Directory of Open Access Journals (Sweden)

    Wang Bo

    2014-07-01

    Full Text Available In order to effectively remove disturbance of shadow and enhance robustness of information processing of computer visual image, this paper makes study on inspection and removal of image shadow. It makes study the continual removal algorithm of shadow based on integration, the illumination surface and texture, it respectively introduces their work principles and realization method, it can effectively carrying processing for shadow by test.

  3. 47 CFR 80.769 - Shadow loss.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Shadow loss. 80.769 Section 80.769... MARITIME SERVICES Standards for Computing Public Coast Station VHF Coverage § 80.769 Shadow loss. Where the transmission path is obstructed the received signal must be adjusted to include shadow loss. Attenuation due to...

  4. Conference Proceedings: Photography and Britishness

    Directory of Open Access Journals (Sweden)

    Sean Willcock

    2016-11-01

    Full Text Available The video-recordings presented here were made at the conference Photography and Britishness, held at the Yale Center for British Art on November 4 – 5, 2016. The conference was the result of a collaboration between the Yale Center for British Art, New Haven, the Paul Mellon Centre for Studies in British Art, London, and the Huntington Library, Art Collections, and Botanical Gardens in San Marino—three research institutions that have a converging interest in British art. The conference sought to investigate the various ways in which notions of “Britishness” have been communicated, inflected, and contested through the photographic image. It was not a conference about the history of photography in Britain, or about British photography. Rather, it sought to consider the nature of the relationship between photography and Britishness: the notion that photography can capture images of Britishness, at the same time that our sense of what Britishness constitutes is produced by the photographic image. A key question for the conference was whether Britishness can have a photographic referent—or whether it is itself an effect of representation. Speakers at the conference approached these questions from a wide range of perspectives and focusing on a diverse number of photographic materials—from family albums and studio portraits to advertisements, reportage, and aerial photography—which demonstrated the complexities and instabilities not only of the term Britishness, but also of the medium of photography. The conference was opened with an introduction by John Tagg. The videos included here are presented in the order they were delivered.

  5. Using Digital Photography to Enhance Student Creativity

    Science.gov (United States)

    Siegle, Del

    2012-01-01

    The purpose of this article is to help students develop their digital photography skills and see the world through new eyes. An emphasis is placed on using digital photography to communicate ideas and feelings. (Contains 6 figures and 2 tables.)

  6. Tropical Storm Ernesto Aerial Photography: Rapid Response Imagery of the Surrounding Regions After Landfall

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The imagery posted on this site is of the surrounding regions after Tropical Storm Ernesto made landfall. The aerial photography missions were conducted by the NOAA...

  7. Hurricane Ike Aerial Photography: Rapid ResponseImagery of the Surrounding Regions After Landfall

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The imagery posted on this site is of the surrounding regionsafter Hurricane Ike made landfall. The aerial photography missions wereconducted by the NOAA Remote...

  8. [True color accuracy in digital forensic photography].

    Science.gov (United States)

    Ramsthaler, Frank; Birngruber, Christoph G; Kröll, Ann-Katrin; Kettner, Mattias; Verhoff, Marcel A

    2016-01-01

    Forensic photographs not only need to be unaltered and authentic and capture context-relevant images, along with certain minimum requirements for image sharpness and information density, but color accuracy also plays an important role, for instance, in the assessment of injuries or taphonomic stages, or in the identification and evaluation of traces from photos. The perception of color not only varies subjectively from person to person, but as a discrete property of an image, color in digital photos is also to a considerable extent influenced by technical factors such as lighting, acquisition settings, camera, and output medium (print, monitor). For these reasons, consistent color accuracy has so far been limited in digital photography. Because images usually contain a wealth of color information, especially for complex or composite colors or shades of color, and the wavelength-dependent sensitivity to factors such as light and shadow may vary between cameras, the usefulness of issuing general recommendations for camera capture settings is limited. Our results indicate that true image colors can best and most realistically be captured with the SpyderCheckr technical calibration tool for digital cameras tested in this study. Apart from aspects such as the simplicity and quickness of the calibration procedure, a further advantage of the tool is that the results are independent of the camera used and can also be used for the color management of output devices such as monitors and printers. The SpyderCheckr color-code patches allow true colors to be captured more realistically than with a manual white balance tool or an automatic flash. We therefore recommend that the use of a color management tool should be considered for the acquisition of all images that demand high true color accuracy (in particular in the setting of injury documentation).

  9. 36 CFR 5.5 - Commercial photography.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Commercial photography. 5.5... COMMERCIAL AND PRIVATE OPERATIONS § 5.5 Commercial photography. (a) Motion pictures, television. Before any... Federal Regulations. (b) Still photography. The taking of photographs of any vehicle, or other articles of...

  10. 36 CFR 1005.5 - Commercial photography.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Commercial photography. 1005... OPERATIONS § 1005.5 Commercial photography. (a) Motion pictures, television. Before any motion picture may be... charge. (Applicant) For (Company) Bond Requirement $ Approved: (Date) (Title) (b) Still photography. The...

  11. Clinical significance of non-mydriatic fundus photography in screening for preschool children ocular fundus disease

    Directory of Open Access Journals (Sweden)

    Jun Luo

    2014-06-01

    Full Text Available AIM: To observe the incidence of ocular fundus disease in preschool children examined by non-mydriatic fundus camera and evaluate its effectiveness compared with direct inspection shadow mirror. METHODS: Three thousand eight hundred and ninety-six preschool children from April 2012 to October 2013 were examined by Topcon TRC-NW300 color fluorescence fundus camera and direct inspection shadow mirror, and images were saved immediately. RESULTS: Detection rate of non-mydriatic fundus photography was higher than that of direct inspection shadow mirror. In 3 896 cases, 41 eyes were detected abnormal fundus accounting for 1.05%. The retinal myelinated nerve fibers, morning glory syndrome, retinitis pigmentosa, congenital retinoschisis were common, accounted for 24.39%, 21.95%, 14.63%, 12.20% respectively. The children eye diseases were often accompanied by abnormal vision(68.30%, ametropia(63.41%, strabismus(19.51%.CONCLUSION: Non-mydriatic fundus photography is a mydriatic method without medicine, so it is easy for preschool children to accept. Image results could directly display the fundus lesions. It shows important significance in the screening for preschool children eye diseases.

  12. On Photography: Uses in Psychotherapy.

    Science.gov (United States)

    Krauss, David

    This paper introduces and defines photography, presents an overview of its applications, and shows how photographs can be used adjunctively as both artifacts and metaphors. Examples are given to demonstrate the usefulness of pictures in gathering information about a client's world, taking a history, formulating a diagnosis, and creating…

  13. Medical photography: principles for orthopedics.

    Science.gov (United States)

    Uzun, Metin; Bülbül, Murat; Toker, Serdar; Beksaç, Burak; Kara, Adnan

    2014-04-05

    Medical photography is used clinically for patient evaluation, treatment decisions, and scientific documentation. Although standards for medical photography exist in many branches of medicine, we have not encountered such criteria in publications in the area of orthopedics. This study aims to (1) assess the quality of medical images used in an orthopedic publication and (2) to propose standards for medical photography in this area. Clinical photographs were reviewed from all issues of a journal published between the years 2008 and 2012. A quality of clinical images was developed based on the criteria published for the specialties of dermatology and cosmetic surgery. All images were reviewed on the appropriateness of background, patient preparation, and technique. In this study, only 44.9% of clinical images in an orthopedic publication adhered to the proposed conventions. Standards have not been established for medical photography in orthopedics as in other specialty areas. Our results suggest that photographic clinical information in orthopedic publications may be limited by inadequate presentation. We propose that formal conventions for clinical images should be established.

  14. [Edgar Degas, photography and voyeurism].

    Science.gov (United States)

    Küchenhoff, J

    1990-08-01

    Degas has drawn his paintings in a voyeuristic perspective. This voyeurism is not due to the painter's personal psychopathology. Instead, Degas has recognized the voyeuristic change of visual perception as a result of the development of photography as a new medium; meanwhile this change has become unconscious. Degas' paintings thus confront us with the historicity of visual perception and of the visual partial instinct.

  15. Creative Composition in Outdoor Photography.

    Science.gov (United States)

    Priest, Simon

    1993-01-01

    This final article in a series of four details the seven steps (ABCDEFG) to creative photography: assess; be creative; compose; depth of field; exposure; focus; and go! Gives tips on picking viewpoints, framing the subject, balancing the picture, and eliminating distractions. Describes techniques for selective focus and selective exposure. (KS)

  16. Digital Photography for Elementary Students

    Science.gov (United States)

    Neckers, Matt

    2009-01-01

    Most elementary students approach photography in an open-minded, experimental way. As a result, their images are often more playful than those taken by adults. Students discover more through their own explorations than they would learn through overly structured lessons. In this article, the author describes how he introduces his elementary…

  17. Signatures of a shadow biosphere.

    Science.gov (United States)

    Davies, Paul C W; Benner, Steven A; Cleland, Carol E; Lineweaver, Charles H; McKay, Christopher P; Wolfe-Simon, Felisa

    2009-03-01

    Astrobiologists are aware that extraterrestrial life might differ from known life, and considerable thought has been given to possible signatures associated with weird forms of life on other planets. So far, however, very little attention has been paid to the possibility that our own planet might also host communities of weird life. If life arises readily in Earth-like conditions, as many astrobiologists contend, then it may well have formed many times on Earth itself, which raises the question whether one or more shadow biospheres have existed in the past or still exist today. In this paper, we discuss possible signatures of weird life and outline some simple strategies for seeking evidence of a shadow biosphere.

  18. Labour Migration and Shadow Prices

    OpenAIRE

    Henry J. Bruton

    1980-01-01

    The effect of migration and home remittances .on the shadow prices of labour and foreign exchange is analysed here, taking into consideration changes in their social marginal productivities.It is argued tha r appreciation of currency, due to large capital inflows and not to increased productivity, results in a misallocation of resources, and, therefore, there is an urgent need for a proper analysis to determine the optimal level of emigrants.

  19. Shadows Cast on the Screen?

    DEFF Research Database (Denmark)

    Jensen, Sisse Siggaard

    , human-computer interaction, and philosophy. However, a common thread of many studies appears to be the understanding that the relations of a person with his or her avatar(s) are representational: The avatar is seen as the virtual representation of the real in-front-of-the-screen person, like a shadow......, DC Aspen. Finally, with reference to the semiotic understanding it is suggested that we see avatars as transformative mediators of communication...

  20. Shadow removal using bilateral filtering.

    Science.gov (United States)

    Yang, Qingxiong; Tan, Kar-Han; Ahuja, Narendra

    2012-10-01

    In this paper, we propose a simple but effective shadow removal method using a single input image. We first derive a 2-D intrinsic image from a single RGB camera image based solely on colors, particularly chromaticity. We next present a method to recover a 3-D intrinsic image based on bilateral filtering and the 2-D intrinsic image. The luminance contrast in regions with similar surface reflectance due to geometry and illumination variances is effectively reduced in the derived 3-D intrinsic image, while the contrast in regions with different surface reflectance is preserved. However, the intrinsic image contains incorrect luminance values. To obtain the correct luminance, we decompose the input RGB image and the intrinsic image. Each image is decomposed into a base layer and a detail layer. We obtain a shadow-free image by combining the base layer from the input RGB image and the detail layer from the intrinsic image such that the details of the intrinsic image are transferred to the input RGB image from which the correct luminance values can be obtained. Unlike previous methods, the presented technique is fully automatic and does not require shadow detection.

  1. Paired regions for shadow detection and removal.

    Science.gov (United States)

    Guo, Ruiqi; Dai, Qieyun; Hoiem, Derek

    2013-12-01

    In this paper, we address the problem of shadow detection and removal from single images of natural scenes. Differently from traditional methods that explore pixel or edge information, we employ a region-based approach. In addition to considering individual regions separately, we predict relative illumination conditions between segmented regions from their appearances and perform pairwise classification based on such information. Classification results are used to build a graph of segments, and graph-cut is used to solve the labeling of shadow and nonshadow regions. Detection results are later refined by image matting, and the shadow-free image is recovered by relighting each pixel based on our lighting model. We evaluate our method on the shadow detection dataset in Zhu et al. In addition, we created a new dataset with shadow-free ground truth images, which provides a quantitative basis for evaluating shadow removal. We study the effectiveness of features for both unary and pairwise classification.

  2. Nail Photography: Tips and Tricks

    OpenAIRE

    Feroze Kaliyadan; K T Ashique

    2016-01-01

    Photographic documentation of the nails is important in the objective evaluation of response to treatment and in disseminating scientific information related to nail diseases. The key to a good image of the nail is proper framing and achieving a sharp focused image with good contrast with the background, at the same time avoiding strong reflections from the nail surface. While the general principles of clinical photography apply to nail imaging also, this article attempts to highlight some ti...

  3. Digital Astronaut Photography: A Discovery Dataset for Archaeology

    Science.gov (United States)

    Stefanov, William L.

    2010-01-01

    Astronaut photography acquired from the International Space Station (ISS) using commercial off-the-shelf cameras offers a freely-accessible source for high to very high resolution (4-20 m/pixel) visible-wavelength digital data of Earth. Since ISS Expedition 1 in 2000, over 373,000 images of the Earth-Moon system (including land surface, ocean, atmospheric, and lunar images) have been added to the Gateway to Astronaut Photography of Earth online database (http://eol.jsc.nasa.gov ). Handheld astronaut photographs vary in look angle, time of acquisition, solar illumination, and spatial resolution. These attributes of digital astronaut photography result from a unique combination of ISS orbital dynamics, mission operations, camera systems, and the individual skills of the astronaut. The variable nature of astronaut photography makes the dataset uniquely useful for archaeological applications in comparison with more traditional nadir-viewing multispectral datasets acquired from unmanned orbital platforms. For example, surface features such as trenches, walls, ruins, urban patterns, and vegetation clearing and regrowth patterns may be accentuated by low sun angles and oblique viewing conditions (Fig. 1). High spatial resolution digital astronaut photographs can also be used with sophisticated land cover classification and spatial analysis approaches like Object Based Image Analysis, increasing the potential for use in archaeological characterization of landscapes and specific sites.

  4. Moving Shadow Detection in Video Using Cepstrum

    Directory of Open Access Journals (Sweden)

    Fuat Cogun

    2013-01-01

    Full Text Available Moving shadows constitute problems in various applications such as image segmentation and object tracking. The main cause of these problems is the misclassification of the shadow pixels as target pixels. Therefore, the use of an accurate and reliable shadow detection method is essential to realize intelligent video processing applications. In this paper, a cepstrum-based method for moving shadow detection is presented. The proposed method is tested on outdoor and indoor video sequences using well-known benchmark test sets. To show the improvements over previous approaches, quantitative metrics are introduced and comparisons based on these metrics are made.

  5. Ocular Fundus Photography as an Educational Tool.

    Science.gov (United States)

    Mackay, Devin D; Garza, Philip S

    2015-10-01

    The proficiency of nonophthalmologists with direct ophthalmoscopy is poor, which has prompted a search for alternative technologies to examine the ocular fundus. Although ocular fundus photography has existed for decades, its use has been traditionally restricted to ophthalmology clinical care settings and textbooks. Recent research has shown a role for nonmydriatic fundus photography in nonophthalmic settings, encouraging more widespread adoption of fundus photography technology. Recent studies have also affirmed the role of fundus photography as an adjunct or alternative to direct ophthalmoscopy in undergraduate medical education. In this review, the authors examine the use of ocular fundus photography as an educational tool and suggest future applications for this important technology. Novel applications of fundus photography as an educational tool have the potential to resurrect the dying art of funduscopy. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  6. Photography and the Limits of Place

    OpenAIRE

    Whittaker, Edward

    2013-01-01

    The study considers how place is historically manifested by the invention of photography. This will be to investigate where photography has developed uses influencing the allocation and administration of places, in particular the early architectural and topographical photography in the history of Paris in the Second and Third Empires of France. The study also examines the affects of the photographic image as an appearance removed from a certainty of the world, yet consisting of an excess of i...

  7. Photography as an Agent of Transformation: Education, Community and Documentary Photography in Post-War Britain

    Science.gov (United States)

    Macnab, Natasha

    2015-01-01

    Radical political activism in the 1970s and 1980s had a huge impact on documentary photography in Britain. Community organisations and photography collectives emerged and endeavoured to democratise the arts for those who would not otherwise have come into contact with them. Community photography used the technology to break down the barriers…

  8. Validation of Smartphone Based Retinal Photography for Diabetic Retinopathy Screening.

    Directory of Open Access Journals (Sweden)

    Ramachandran Rajalakshmi

    Full Text Available To evaluate the sensitivity and specificity of "fundus on phone' (FOP camera, a smartphone based retinal imaging system, as a screening tool for diabetic retinopathy (DR detection and DR severity in comparison with 7-standard field digital retinal photography.Single-site, prospective, comparative, instrument validation study.301 patients (602 eyes with type 2 diabetes underwent standard seven-field digital fundus photography with both Carl Zeiss fundus camera and indigenous FOP at a tertiary care diabetes centre in South India. Grading of DR was performed by two independent retina specialists using modified Early Treatment of Diabetic Retinopathy Study grading system. Sight threatening DR (STDR was defined by the presence of proliferative DR(PDR or diabetic macular edema. The sensitivity, specificity and image quality were assessed.The mean age of the participants was 53.5 ±9.6 years and mean duration of diabetes 12.5±7.3 years. The Zeiss camera showed that 43.9% had non-proliferative DR(NPDR and 15.3% had PDR while the FOP camera showed that 40.2% had NPDR and 15.3% had PDR. The sensitivity and specificity for detecting any DR by FOP was 92.7% (95%CI 87.8-96.1 and 98.4% (95%CI 94.3-99.8 respectively and the kappa (ĸ agreement was 0.90 (95%CI-0.85-0.95 p<0.001 while for STDR, the sensitivity was 87.9% (95%CI 83.2-92.9, specificity 94.9% (95%CI 89.7-98.2 and ĸ agreement was 0.80 (95%CI 0.71-0.89 p<0.001, compared to conventional photography.Retinal photography using FOP camera is effective for screening and diagnosis of DR and STDR with high sensitivity and specificity and has substantial agreement with conventional retinal photography.

  9. Validation of Smartphone Based Retinal Photography for Diabetic Retinopathy Screening.

    Science.gov (United States)

    Rajalakshmi, Ramachandran; Arulmalar, Subramanian; Usha, Manoharan; Prathiba, Vijayaraghavan; Kareemuddin, Khaji Syed; Anjana, Ranjit Mohan; Mohan, Viswanathan

    2015-01-01

    To evaluate the sensitivity and specificity of "fundus on phone' (FOP) camera, a smartphone based retinal imaging system, as a screening tool for diabetic retinopathy (DR) detection and DR severity in comparison with 7-standard field digital retinal photography. Single-site, prospective, comparative, instrument validation study. 301 patients (602 eyes) with type 2 diabetes underwent standard seven-field digital fundus photography with both Carl Zeiss fundus camera and indigenous FOP at a tertiary care diabetes centre in South India. Grading of DR was performed by two independent retina specialists using modified Early Treatment of Diabetic Retinopathy Study grading system. Sight threatening DR (STDR) was defined by the presence of proliferative DR(PDR) or diabetic macular edema. The sensitivity, specificity and image quality were assessed. The mean age of the participants was 53.5 ±9.6 years and mean duration of diabetes 12.5±7.3 years. The Zeiss camera showed that 43.9% had non-proliferative DR(NPDR) and 15.3% had PDR while the FOP camera showed that 40.2% had NPDR and 15.3% had PDR. The sensitivity and specificity for detecting any DR by FOP was 92.7% (95%CI 87.8-96.1) and 98.4% (95%CI 94.3-99.8) respectively and the kappa (ĸ) agreement was 0.90 (95%CI-0.85-0.95 p<0.001) while for STDR, the sensitivity was 87.9% (95%CI 83.2-92.9), specificity 94.9% (95%CI 89.7-98.2) and ĸ agreement was 0.80 (95%CI 0.71-0.89 p<0.001), compared to conventional photography. Retinal photography using FOP camera is effective for screening and diagnosis of DR and STDR with high sensitivity and specificity and has substantial agreement with conventional retinal photography.

  10. Alorithm for Shadow Detection in Real Colour Images

    OpenAIRE

    Sanjeev Kumar,; Anupreet Kaur

    2010-01-01

    Shadow detection in real scene images is always a challenging but yet interesting area. Most shadow detection and segmentation methods are based on image analysis. This paper aimed to give a comprehensive and critical study of current shadow detection methods. Various approaches have been discussed related to shadow detection in images. The principles of these methods rely on intensity difference or texture analysis of the shadow area and the bright area of the same surface. A realtime shadow...

  11. Shadow detection using a physical basis

    NARCIS (Netherlands)

    Withagen, P.J.; Groen, F.C.A.; Schutte, K.

    2008-01-01

    Shadow detection is an important aspect of foreground/ background classification. Many techniques exist, most of them assuming that casting a shadow results only in a change in intensity and no change in color. In this paper we show that in most practical indoor and outdoor situations there will

  12. Detection of Cast Shadows in Surveillance Applications

    DEFF Research Database (Denmark)

    Erbou, Søren G.; Sørensen, Helge Bjarne Dissing; Stage, Bjarne

    2005-01-01

    Cast shadows from moving objects reduce the general ability of robust classification and tracking of these objects, in outdoor surveillance applications. A method for segmentation of cast shadows is proposed, combining statistical features with a new similarity feature, derived from a physics...

  13. Shadow detection using a physical basis

    NARCIS (Netherlands)

    Groen, F.C.A.; Withagen, P.J.; Schutte, K.

    2007-01-01

    Shadow detection is an important aspect of foreground/background classification. Many techniques exist, most of them assuming that only the intensity changes under shadow. In this paper we show that in most practical indoor and outdoor situations there will also be a color shift. We propose an

  14. Shadow-free single-pixel imaging

    Science.gov (United States)

    Li, Shunhua; Zhang, Zibang; Ma, Xiao; Zhong, Jingang

    2017-11-01

    Single-pixel imaging is an innovative imaging scheme and receives increasing attention in recent years, for it is applicable for imaging at non-visible wavelengths and imaging under weak light conditions. However, as in conventional imaging, shadows would likely occur in single-pixel imaging and sometimes bring negative effects in practical uses. In this paper, the principle of shadows occurrence in single-pixel imaging is analyzed, following which a technique for shadows removal is proposed. In the proposed technique, several single-pixel detectors are used to detect the backscattered light at different locations so that the shadows in the reconstructed images corresponding to each detector shadows are complementary. Shadow-free reconstruction can be derived by fusing the shadow-complementary images using maximum selection rule. To deal with the problem of intensity mismatch in image fusion, we put forward a simple calibration. As experimentally demonstrated, the technique is able to reconstruct monochromatic and full-color shadow-free images.

  15. Extensive Reading and the Effect of Shadowing

    Science.gov (United States)

    Nakanishi, Takayuki; Ueda, Atsuko

    2011-01-01

    The aim of this study is to investigate the effects of extensive reading (ER) and shadowing on performance on reading comprehension tests. This study addressed the following research questions: (a) Can extensive reading improve students' reading comprehension? and (b) can shadowing enhance the effects of extensive reading? The participants in the…

  16. Tricolor attenuation model for shadow detection.

    Science.gov (United States)

    Tian, Jiandong; Sun, Jing; Tang, Yandong

    2009-10-01

    Shadows, the common phenomena in most outdoor scenes, bring many problems in image processing and computer vision. In this paper, we present a novel method focusing on extracting shadows from a single outdoor image. The proposed tricolor attenuation model (TAM) that describe the attenuation relationship between shadow and its nonshadow background is derived based on image formation theory. The parameters of the TAM are fixed by using the spectral power distribution (SPD) of daylight and skylight, which are estimated according to Planck's blackbody irradiance law. Based on the TAM, a multistep shadow detection algorithm is proposed to extract shadows. Compared with previous methods, the algorithm can be applied to process single images gotten in real complex scenes without prior knowledge. The experimental results validate the performance of the model.

  17. Nail photography: Tips and tricks

    Directory of Open Access Journals (Sweden)

    Feroze Kaliyadan

    2016-01-01

    Full Text Available Photographic documentation of the nails is important in the objective evaluation of response to treatment and in disseminating scientific information related to nail diseases. The key to a good image of the nail is proper framing and achieving a sharp focused image with good contrast with the background, at the same time avoiding strong reflections from the nail surface. While the general principles of clinical photography apply to nail imaging also, this article attempts to highlight some tips which can be specifically used to improve the quality of nail images.

  18. Nail Photography: Tips and Tricks.

    Science.gov (United States)

    Kaliyadan, Feroze; Ashique, K T

    2016-01-01

    Photographic documentation of the nails is important in the objective evaluation of response to treatment and in disseminating scientific information related to nail diseases. The key to a good image of the nail is proper framing and achieving a sharp focused image with good contrast with the background, at the same time avoiding strong reflections from the nail surface. While the general principles of clinical photography apply to nail imaging also, this article attempts to highlight some tips which can be specifically used to improve the quality of nail images.

  19. ASI/MET shadow & airbags

    Science.gov (United States)

    1997-01-01

    A shadow of the Atmospheric Structure Instrument/Meteorology Package (ASI/MET) has been cast on a rock at right in this image, taken by the Imager for Mars Pathfinder (IMP) on Sol 4. The instrument appears in two different sections due to image parallax. The ASI/MET is an engineering subsytem that acquired atmospheric data during Pathfinder's descent, and will continue to get more data through the entire landed mission. Portions of a lander petal and deflated airbag are visible, in addition to several rocks of varying sizes in the distance.Mars Pathfinder was developed and managed by the Jet Propulsion Laboratory (JPL) for the National Aeronautics and Space Administration. JPL is an operating division of the California Institute of Technology (Caltech). The IMP was developed by the University of Arizona Lunar and Planetary Laboratory under contract to JPL. Peter Smith is the Principal Investigator.

  20. Application II: Search Arts and Sports Photography

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Application II: Search Arts and Sports Photography. Depth variation induces defocus. Defocus blur is severe in nature and sports photography. Given a low DOF image, segment the focused region and retrieve the images based similarities in the focused region.

  1. Using Photography to Tell a Story

    Science.gov (United States)

    Thompson, Susan; Williams, Kayenta

    2008-01-01

    Photography can be an exciting way to integrate art and creativity into social studies. Photography allows students to use creative self-expression in revealing the symbolism in historic places, people, or scenes with a richness that words alone often cannot accomplish. In this article, the authors provide several ideas for creating photo essays.…

  2. "It's as If…" Preschoolers Encountering Contemporary Photography

    Science.gov (United States)

    Rissanen, Mari-Jatta

    2017-01-01

    This article reports a study on an encounter between preschoolers and contemporary photography. The article has two aims: first, it elucidates preschoolers' meaning-making when viewing photographs, and second, it investigates the possible benefits of using contemporary photography as a forum for prompting children's aesthetic agency in early…

  3. 50 CFR 216.42 - Photography. [Reserved

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Photography. 216.42 Section 216.42 Wildlife and Fisheries NATIONAL MARINE FISHERIES SERVICE, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION... Special Exceptions § 216.42 Photography. ...

  4. Dental photography today. Part 1: basic concepts.

    Science.gov (United States)

    Casaglia, A; DE Dominicis, P; Arcuri, L; Gargari, M; Ottria, L

    2015-01-01

    This paper is the first article in a new series on digital dental photography. Part 1 defines the aims and objectives of dental photography for examination, diagnosis and treatment planning, legal and forensic documentation, publishing, education, marketing and communication with patients, dental team members, colleagues and dental laboratory.

  5. Photography and plastic surgery: part 1.

    Science.gov (United States)

    Spear, Marcia; Hagan, Kevin

    2008-01-01

    Plastic surgery and photography are inseparable and with present-day technology, it is much easier and more affordable than ever before to incorporate high-quality and standardized images into clinical practice. Perfecting digital photography can have a learning curve that is many times hindered by old habits from the days of slide photography, macro lenses, and specialized flashes, which made it more difficult and complex to incorporate into a busy plastic surgery practice. With the current digital revolution, many of these barriers have been or can be eliminated and anyone can become a proficient photographer. The purpose of this article, first in a series, is to introduce the plastic surgical nurse to the history of photography and applications and the benefits of digital photography.

  6. Ophthalmic photography using a digital camera.

    Directory of Open Access Journals (Sweden)

    Fogla Rajesh

    2003-01-01

    Full Text Available Purpose: To report the application of a digital camera for ophthalmic photography in routine clinical use. Methods: A digital camera (Nikon Coolpix 995 was used both for external macrophotography of the eye and ocular adnexa, and slitlamp photography of the anterior segment of the eye. Results: We were able to take external macrophotographs under high magnification of the eye and ocular adnexa. Slitlamp photography could be performed under diffuse, slit beam, and retroillumination. The structures of the angle, the optic disc and surrounding retina could be photographed using appropriate lenses. The attachment to the operating microscope allowed intra-operative photography. It could also be attached to the laboratory microscope to capture images of various histopathology and microbiology slides. Conclusions: A digital camera is a versatile instrument for ophthalmic photography. It is easy to use in routine clinical practice and provides good quality photographs.

  7. Spectral anomaly detection in deep shadows.

    Science.gov (United States)

    Kanaev, Andrey V; Murray-Krezan, Jeremy

    2010-03-20

    Although several hyperspectral anomaly detection algorithms have proven useful when illumination conditions provide for enough light, many of these same detection algorithms fail to perform well when shadows are also present. To date, no general approach to the problem has been demonstrated. In this paper, a novel hyperspectral anomaly detection algorithm that adapts the dimensionality of the spectral detection subspace to multiple illumination levels is described. The novel detection algorithm is applied to reflectance domain hyperspectral data that represents a variety of illumination conditions: well illuminated and poorly illuminated (i.e., shadowed). Detection results obtained for objects located in deep shadows and light-shadow transition areas suggest superiority of the novel algorithm over standard subspace RX detection.

  8. The Shadow Sphere in International Relations

    Directory of Open Access Journals (Sweden)

    A N Mikhailenko

    2012-06-01

    Full Text Available The article deals with the shadow sphere in international relations. Approaches to its classification are proposed, main principles of its functioning and influence on world politics are analyzed.

  9. The little book of light and shadow

    CERN Document Server

    Thornton, Linda

    2013-01-01

    Encourage your Early Learners to becom investigators by exploring the concept of light and shadow. These simple and effective activities can be carried out independently with the focus on natural resources.

  10. Fading and shadowing in wireless systems

    CERN Document Server

    Shankar, P Mohana

    2017-01-01

    This book offers a comprehensive overview of fading and shadowing in wireless channels. A number of statistical models including simple, hybrid, compound and cascaded ones are presented along with a detailed discussion of diversity techniques employed to mitigate the effects of fading and shadowing. The effects of co-channel interference before and after the implementation of diversity are also analyzed. To facilitate easy understanding of the models and the analysis, the background on probability and random variables is presented with relevant derivations of densities of the sums, products, ratios as well as order statistics of random variables. The book also provides material on digital modems of interest in wireless systems. The updated edition expands the background materials on probability by offering sections on Laplace and Mellin transforms, parameter estimation, statistical testing and receiver operating characteristics. Newer models for fading, shadowing and shadowed fading are included along with th...

  11. Evaluation of Digital Shadow Economy Prevention Measures

    Directory of Open Access Journals (Sweden)

    Remeikiene Rita

    2016-06-01

    Full Text Available Although during the past few years the scopes of shadow economy in Lithuania have slightly decreased, different forms of this phenomenon, in particular digital shadow activities, still generate a significant part of the overall value added. As no constant estimations of the scope of digital shadow economy have been made in Lithuania, alleviation of this problem is based on consequence fighting rather than reason elimination. Digital shadow economy poses a significant challenge for law enforcement agencies concerning its investigation and prevention. Hence, it is purposeful to research both theoretical and practical aspects of digital shadow economy prevention in order to identify the measures that could be used for the efficient reduction of the scope of this phenomenon. The aim of this research is to identify the measures of digital shadow economy prevention and compare the attitudes of governmental institutions and consumers towards the efficiency of these measures. The results of the empirical research showed that both consumers and experts agree that the level of tax morale has to be raised not only by using the measures of self-education but also by introducing long-term educational programmes; second, public authorities should ensure business friendly environment, actively implement the principles of justice and officially acknowledge and announce the concept of digital shadow economy; finally, for more efficient detection of the cases of digital shadow activities, it is necessary to reinforce current labour resources that should be specially trained to be able to disclose revenue hiding and tax evasion schemes, employed in e-trade.

  12. Boundary Correct Real-Time Soft Shadows

    DEFF Research Database (Denmark)

    Jacobsen, Bjarke; Christensen, Niels Jørgen; Larsen, Bent Dalgaard

    2004-01-01

    This paper describes a method to determine correct shadow boundaries from an area light source using umbra and penumbra volumes. The light source is approximated by a circular disk as this gives a fast way to extrude the volumes. The method also gives a crude estimate of the visibility of the area...... for implementation on most programmable hardware. Though some crude approximations are used in the visibility function, the method can be used to produce soft shadows with correct boundaries in real time....

  13. 7 CFR 611.21 - Availability of aerial photography.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Availability of aerial photography. 611.21 Section 611... § 611.21 Availability of aerial photography. The National Cartography and Geospatial Center obtains necessary clearance for all aerial photography for NRCS. New aerial photography of designated areas in the...

  14. 77 FR 36250 - Information Collection Request; Request for Aerial Photography

    Science.gov (United States)

    2012-06-18

    ...; ] DEPARTMENT OF AGRICULTURE Farm Service Agency Information Collection Request; Request for Aerial Photography... FSA Aerial Photography Program. The FSA Aerial Photography Field Office (APFO) uses the information from this form to collect the customer and photography information needed to produce and ship the...

  15. Affordable, Accessible, Immediate: Capture Stunning Images with Digital Infrared Photography

    Science.gov (United States)

    Snyder, Mark

    2011-01-01

    Technology educators who teach digital photography should consider incorporating an infrared (IR) photography component into their program. This is an area where digital photography offers significant benefits. Either type of IR imaging is very interesting to explore, but traditional film-based IR photography is difficult and expensive. In…

  16. [re]connect: Postmodern Documentary Photography Symposium and Traveling Exhibition

    OpenAIRE

    Kim Park, Min; Soon-Hwa, Oh

    2014-01-01

    The Postmodern Documentary Photography Exhibition features selected works from leading artists in the field of contemporary documentary photography. Their research focuses on finding new ways to portray 'truth' through photography, exploring new subject matter in unique locations, confronting societal expectations and social norms, and discovering new ways of enhancing documentary photography in the digital age. Min Kim Park, director of Postmodern Documentary Photography Exhibition, discusse...

  17. Photography in Use in Environmental Science

    Science.gov (United States)

    Parker, Donald C.

    1974-01-01

    Described are some uses of a 35mm single lens reflex camera as a tool for the applied study of ecology. Photography is discussed in relation to field trips, ecosystems, general ecological concepts, pollution, and special projects. (PEB)

  18. Extracting Leaf Area Index by Sunlit Foliage Component from Downward-Looking Digital Photography under Clear-Sky Conditions

    Directory of Open Access Journals (Sweden)

    Yelu Zeng

    2015-10-01

    Full Text Available The development of near-surface remote sensing requires the accurate extraction of leaf area index (LAI from networked digital cameras under all illumination conditions. The widely used directional gap fraction model is more suitable for overcast conditions due to the difficulty to discriminate the shaded foliage from the shadowed parts of images acquired on sunny days. In this study, a new LAI extraction method by the sunlit foliage component from downward-looking digital photography under clear-sky conditions is proposed. In this method, the sunlit foliage component was extracted by an automated image classification algorithm named LAB2, the clumping index was estimated by a path length distribution-based method, the LAD and G function were quantified by leveled digital images and, eventually, the LAI was obtained by introducing a geometric-optical (GO model which can quantify the sunlit foliage proportion. The proposed method was evaluated at the YJP site, Canada, by the 3D realistic structural scene constructed based on the field measurements. Results suggest that the LAB2 algorithm makes it possible for the automated image processing and the accurate sunlit foliage extraction with the minimum overall accuracy of 91.4%. The widely-used finite-length method tends to underestimate the clumping index, while the path length distribution-based method can reduce the relative error (RE from 7.8% to 6.6%. Using the directional gap fraction model under sunny conditions can lead to an underestimation of LAI by (1.61; 55.9%, which was significantly outside the accuracy requirement (0.5; 20% by the Global Climate Observation System (GCOS. The proposed LAI extraction method has an RMSE of 0.35 and an RE of 11.4% under sunny conditions, which can meet the accuracy requirement of the GCOS. This method relaxes the required diffuse illumination conditions for the digital photography, and can be applied to extract LAI from downward-looking webcam images

  19. Education for Sustainability through a Photography Competition

    OpenAIRE

    Rowena Scott

    2014-01-01

    This article describes the development and history of a sustainability photography competition. From its simple beginnings as an environmental officer’s idea, an environmental sustainability photography competition began in just one university. Now hosted by Australasian Campuses Towards Sustainability (ACTS), finalist entries are viewed on a public website gaining international attention. A purpose of this article is to demonstrate the diversity of views of sustainability by displaying the w...

  20. Patient perspectives on medical photography in dermatology.

    Science.gov (United States)

    Leger, Marie C; Wu, Timothy; Haimovic, Adele; Kaplan, Rachel; Sanchez, Miguel; Cohen, David; Leger, Elizabeth A; Stein, Jennifer A

    2014-09-01

    Clinical photography enhances medical care, research, and teaching. Empirical data are needed to guide best practices regarding dermatologic photography. To investigate patient opinion about clinical photography and identify demographic factors that influence these opinions. Four hundred patients representing a broad range of ages, self-identified ethnic/racial groups, and socioeconomic levels were recruited from 4 dermatology settings in New York City. Patients were administered a survey about perceptions of photography, willingness to allow photographs to be used in a variety of settings, preferences for photographer and photographic equipment, and methods of consent. Eighty-eight percent of patients agreed that photography enhanced their quality of care. Most patients would allow their photographs to be used for medical, teaching, and research purposes with significantly more acceptance when patients were not identifiable. Patients preferred photographs taken by a physician rather than a nurse or student, photographers of the same gender, clinic-owned cameras to personal cameras or cell phones, and written consent to verbal consent. There were significant racial/ethnicity and age-related variations in responses, with white and older patients being more permissive than other groups. We use the results of this study to recommend best practices for photography in dermatology.

  1. Leaking privacy and shadow profiles in online social networks.

    Science.gov (United States)

    Garcia, David

    2017-08-01

    Social interaction and data integration in the digital society can affect the control that individuals have on their privacy. Social networking sites can access data from other services, including user contact lists where nonusers are listed too. Although most research on online privacy has focused on inference of personal information of users, this data integration poses the question of whether it is possible to predict personal information of nonusers. This article tests the shadow profile hypothesis, which postulates that the data given by the users of an online service predict personal information of nonusers. Using data from a disappeared social networking site, we perform a historical audit to evaluate whether personal data of nonusers could have been predicted with the personal data and contact lists shared by the users of the site. We analyze personal information of sexual orientation and relationship status, which follow regular mixing patterns in the social network. Going back in time over the growth of the network, we measure predictor performance as a function of network size and tendency of users to disclose their contact lists. This article presents robust evidence supporting the shadow profile hypothesis and reveals a multiplicative effect of network size and disclosure tendencies that accelerates the performance of predictors. These results call for new privacy paradigms that take into account the fact that individual privacy decisions do not happen in isolation and are mediated by the decisions of others.

  2. Improving Students’ Listening Skill Through Shadowing

    Directory of Open Access Journals (Sweden)

    Mukminatus Zuhriyah

    2016-12-01

    Full Text Available Listening is the first part of language skills that everyone gets when learning a language. It comes before speaking, reading, and writing. Meanwhile, most of the students get difficulty to learn listening of a foreign language, especially English. That is why shadowing was applied in the listening class as one of the solutions to make the learners of English listening easy to understand what the speaker says. This collaborative classroom action research was generally to know whether or not shadowing could improve the students listening skill. It was also specifically to know: (1 the lecturer’s activities, (2 the students’ activities, and (3 the students’ responses during the implementation of shadowing in the listening class. The subjects were 18 students of the third semester of English department of education faculty of Hasyim Asy’ari university (UNHASY Tebuireng Jombang in the academic year of 2016/2017. The data were obtained from the observations got from the notes written by the collaborator and the listening test. The students’ listening skill improved after the implementation of shadowing. It could be seen in the improvement of mean score, from 74.2 in cycle one to 75 in cycle two. Then, the precentage of students passing the minimum mastery criteria also improved, from 61% in cycle one to 77.8% in cycle two. Thus, it can be concluded that shadowing could improve students’ listening skill.

  3. What shadows reveal about object structure.

    Science.gov (United States)

    Kriegman, D J; Belhumeur, P N

    2001-08-01

    In a scene observed from a fixed viewpoint, the set of shadow boundaries in an image changes as a point light source (nearby or at infinity) assumes different locations. We show that for any finite set of point light sources illuminating an object viewed under either orthographic or perspective projection, there is an equivalence class of object shapes having the same set of shadows. Members of this equivalence class differ by a four-parameter family of projective transformations, and the shadows of a transformed object are identical when the same transformation is applied to the light source locations. Under orthographic projection, this family is the generalized bas-relief (GBR) transformation, and we show that the GBR transformation is the only family of transformations of an object's shape for which the complete set of imaged shadows is identical. Finally, we show that given multiple images under differing and unknown light source directions, it is possible to reconstruct both an object's surface and the light source locations up to this family of transformations from the shadows alone.

  4. Using aerial photography and image analysis to measure changes in giant reed populations

    Science.gov (United States)

    A study was conducted along the Rio Grande in southwest Texas to evaluate color-infrared aerial photography combined with supervised image analysis to quantify changes in giant reed (Arundo donax L.) populations over a 6-year period. Aerial photographs from 2002 and 2008 of the same seven study site...

  5. Robert Taft in Beaumont Newhall’s Shadow

    OpenAIRE

    Brunet, François

    2014-01-01

    This paper examines the historical coincidence, conceptual difference, and generative dialogue linking the two accounts of photography's first century, created simultaneously by the American historians Beaumont Newhall and Robert Taft. Whereas Newhall's catalogue to the 1937 MoMA exhibition and subsequent History of Photography have long been considered foundational documents for the aesthetic interpretation of photography, Taft's 1938 Photography and the American Scene has been given very li...

  6. Nightscape Photography Reclaims the Natural Sky

    Science.gov (United States)

    Tafreshi, Babak

    2015-08-01

    Nightscape photos and timelapse videos, where the Earth & sky are framed together with an astronomical purpose, support the dark skies activities by improving public awareness. TWAN or The World at Night program (www.twanight.org) presents the world's best collection of such landscape astrophotos and aims to introduce the night sky as a part of nature, an essential element of our living environment besides being the astronomers lab. The nightscape images also present views of our civilizations landmarks, both natural and historic sites, against the night-time backdrop of stars, planets, and celestial events. In this context TWAN is a bridge between art, science and culture.TWAN images contribute to programs such as the Dark Sky Parks by the International Dark Sky Association or Starlight reserves by assisting local efforts in better illustrating their dark skies and by producing stunning images that not only educate the local people on their night sky heritage also communicate with the governments that are responsible to support the dark sky area.Since 2009 TWAN organizes the world's largest annual photo contest on nightscape imaging, in collaboration with the Dark Skies Awareness, National Optical Astronomy Observatory, and Astronomers Without Borders. The International Earth & Sky Photo Contest promotes the photography that documents the beauty of natural skies against the problem of light pollution. In 2014 the entries received from about 50 countries and the contest result news was widely published in the most popular sources internationally.*Babak A. Tafreshi is a photographer and science communicator. He is the creator of The World At Night program, and a contributing photographer to the National Geographic, Sky&Telescope magazine, and the European Southern Observatory. http://twanight.org/tafreshi

  7. The Hero and His Shadow

    Directory of Open Access Journals (Sweden)

    Simona Micali

    2010-08-01

    Full Text Available

     

    Abstract (E: This essay traces the literary theme of the ‘disobedient shadow’ from the Romantic archetype to its adaptation nineteenth- and twentieth-century fantastic fiction. Focusing on texts in which the shadow takes up its own identity, becoming an uncanny double of its master, it is argued that the development of this theme is closely linked with the evolution of the human subject through the epistemological and cultural revolutions of the last two centuries.

    Abstract (F:

     

    Cet article retrace l’évolution du thème littéraire de l’ « ombre désobéissante », de l’archétype romantique aux mutations ultérieures dans la fiction fantastique des 19e et 20e siècles. Il examine un corpus où l’ombre assume son indépendance, devenant un double de son maître dans un esprit que l’on sait être maintenant celui de l

  8. Moving Shadow Detection in Video Using Cepstrum Regular Paper

    OpenAIRE

    Cogun, Fuat; Cetin, Ahmet Enis

    2013-01-01

    Moving shadows constitute problems in various applications such as image segmentation and object tracking. The main cause of these problems is the misclassification of the shadow pixels as target pixels. Therefore, the use of an accurate and reliable shadow detection method is essential to realize intelligent video processing applications. In this paper, a cepstrum‐based method for moving shadow detection is presented. The proposed method is tested on outdoor and indoor video sequences using ...

  9. Infants' perception of lightness changes related to cast shadows.

    Directory of Open Access Journals (Sweden)

    Kazuki Sato

    Full Text Available When humans perceive the lightness of an object's surface in shadows there is an implicit assumption that cast shadows dim the surface. In two experiments, we investigated whether 5- to 8-month-old infants make this assumption about shadows. According to this shadow assumption, the apparent change in lightness produced by shadows on an object's surface are attributed to blocked light sources. If infants can use the shadow assumption to perceive the object's lightness in shadows, they will also be able to detect unnatural lightness changes in shadows. We compared the infants' looking times to the unnatural and the natural lightness changes in the shadow when an object (duck goes through the cast shadow. In Experiment 1, we examined whether infants could detect the unnatural lightness changes of the object's surface in shadows. We created computer-graphic movies of unnatural and natural lightness changes to the duck's surface. Our results showed that 7- to 8-month-olds but not 5- to 6-month-olds significantly preferred the movie with the unnatural changes in lightness, indicating that only the older infants could detect these changes. In Experiment 2, we confirmed that the infants' preference was based on the detection of unnatural lightness changes according to the shadow assumption. The natural and the unnatural lightness changes of Experiment 1 were presented without cast shadows. Under these conditions, neither younger nor older infants showed a significant preference. Taken together, the experiments showed that 7- to 8-month-old infants could detect the unnaturalness of a surface's lightness changes produced by shadows. In conclusion, our findings suggest that 7- to 8-month-old infants can perceive an object's lightness in shadows by using an assumption that cast shadows dim the surface of an object.

  10. Chromatic Shadow Detection and Tracking for Moving Foreground Segmentation

    DEFF Research Database (Denmark)

    Huerta, Ivan; Holte, Michael Boelstoft; Moeslund, Thomas B.

    2015-01-01

    chrominance angle and brightness distortions are analysed for each potential shadow region for detecting the umbra shadow regions. Our second contribution refines even further the segmentation results: a tracking-based top-down approach increases the performance of our bottom-up chromatic shadow detection...

  11. SHADOW PROCESSES INSTATE BUDGET: CURRENT CONDITION AND DETERMINING FACTORS

    Directory of Open Access Journals (Sweden)

    Z. Varnalii

    2014-12-01

    Full Text Available The most significant factors that move state budget into the shadow are determined. Current condition of shadow processes in state budget is highlighted. The paper also provides an analysis of relationship between political processes and shadow economy in public sector of Ukraine.

  12. Ethereal presences in holography and photography

    Science.gov (United States)

    Richardson, M.; Byrne, Kay

    2007-02-01

    This paper examines the concept of the 'Presence of Absence' in post-mortem photography and holography, drawing upon both historical and lesser-known images as reference. To create a photographic negative one needs the presence of light to expose the light sensitive surface, be it glass, a polished plate or plastic. A hologram may also be created when a coherent light source, for example from a Laser, travels through a light sensitive material and falls upon the subject to be recorded. A holograph however, retains the optical qualities of both phase and amplitude, the memory of light. Both mediums recall, as it were, 'now absent moments', and confronts us with what is 'not there' as much as 'what is'. This paper examines the exploration of absence and presence in post-mortem photography and holography and it's a richly visceral visual language. A photonic syntax can interpret death as an elegant yet horrific aesthetic, the photograph may be beautify screened and yet obscene in its content. In essence one can be a voyeur, experiencing a mere visual whisper of the true nature of the subject. Our Victorian forefathers explored postmortem photography as an object of mourning, and at the close of the nineteenth century when Jack the Ripper had the inhabitants of White Chapel in a grip of fear, photography made its mark as a documentation of violent crime. Today, within contemporary photography, death is now presented within the confines of the 'Art Gallery', as a sensual, and at times, sensationalised art form. In exploring post-mortem imagery, both in holography and conventional photography, absence presents an aspect of death as startling in its unanimated form and detailed in its finite examination of mortality.

  13. Innovation as improvisation 'in the shadow'

    DEFF Research Database (Denmark)

    Larsen, Henry; Bogers, Marcel

    2014-01-01

    — happening ‘below the radar’ — which may unpredictably offer windows of opportunity to enable change. We show that innovation often emerges as ‘shadow themes’, experienced as subversive by those involved in the moments of interaction. While these themes are embedded in informal conversations and processes...

  14. ELL Shadowing as a Catalyst for Change

    Science.gov (United States)

    Soto, Ivannia

    2012-01-01

    What if you could barely understand what your teacher was saying? Imagine working mostly independently and silently, with limited opportunities to interact with others. ELL shadowing helps teachers better understand the classroom experience from an English language learner's point of view. The author describes how to implement this easily…

  15. Job Shadowing Introduces the Realities of Manufacturing

    Science.gov (United States)

    Frawley, Thomas A.

    2009-01-01

    Engineers and skilled tradesmen stood side by side with executives and politicians as Liverpool High School technology teacher Dan Drogo welcomed parents to a one-of-a-kind graduation ceremony at New Process Gear in Syracuse, New York. The manufacturing shadow program had immersed 25 high school students in an intensive five-week experience inside…

  16. Hunting the Shadow, Catching the Light

    DEFF Research Database (Denmark)

    Toft, Anne Elisabeth; Nielsen, Torben

    2009-01-01

    From 28 October to 6 November 2009 twenty-one 3rd year students in interior design from Central Academy of Fine Arts (CAFA), School of Architecture, Beijing participated in the workshop Hunting the Shadow - Catching the Light. The workshop was conceived and led by the Danish architects Torben...

  17. Citizenship at the Boundaries. Participative Photography

    Directory of Open Access Journals (Sweden)

    Edwin Alfredo Cubillos Rodríguez

    2012-08-01

    Full Text Available The article discusses the practices of participative photography in the construction of child and adolescent citizenship in contexts of exclusion and sociopolitical violence in urban peripheries. On the basis of the community project, Shooting Cameras, in Cazucá, it argues that in contexts of non-citizenship and community breakdown, characterized by the restriction of democratic action and of the constitution of civil societies, it is possible for daily citizenship practices to emerge through photography. In this context, boys, girls, and teenagers become cultural agents who interpellate traditional forms of participation, thus contributing elements for the configuration of a new subject of citizenship.

  18. Enumerating Photography from Spot Meter to CCD

    OpenAIRE

    Cubitt, Sean; Palmer, Daniel; Walkling, Les

    2015-01-01

    The transition from analogue to digital photography was not accomplished in a single step. It required a number of feeder technologies which enabled and structured the nature of digital photography. Among those traced in this article, the most important is the genesis of the raster grid, which is now hard-wired into the design of the most widely employed photographic chip, the charge-coupled device (CCD). In tracing this history from origins in half-tone printing, the authors argue that quali...

  19. Pitfalls in colour photography of choroidal tumours.

    Science.gov (United States)

    Schalenbourg, A; Zografos, L

    2013-02-01

    Colour imaging of fundus tumours has been transformed by the development of digital and confocal scanning laser photography. These advances provide numerous benefits, such as panoramic images, increased contrast, non-contact wide-angle imaging, non-mydriatic photography, and simultaneous angiography. False tumour colour representation can, however, cause serious diagnostic errors. Large choroidal tumours can be totally invisible on angiography. Pseudogrowth can occur because of artefacts caused by different methods of fundus illumination, movement of reference blood vessels, and flattening of Bruch's membrane and sclera when tumour regression occurs. Awareness of these pitfalls should prevent the clinician from misdiagnosing tumours and wrongfully concluding that a tumour has grown.

  20. Education for Sustainability through a Photography Competition

    Directory of Open Access Journals (Sweden)

    Rowena Scott

    2014-01-01

    Full Text Available This article describes the development and history of a sustainability photography competition. From its simple beginnings as an environmental officer’s idea, an environmental sustainability photography competition began in just one university. Now hosted by Australasian Campuses Towards Sustainability (ACTS, finalist entries are viewed on a public website gaining international attention. A purpose of this article is to demonstrate the diversity of views of sustainability by displaying the winning entries from 2013 and 2012. It is anticipated that readers may replicate these ideas in creative arts and across disciplines throughout primary, secondary and other higher education institutions, community groups and diverse organizations.

  1. Pitfalls in colour photography of choroidal tumours

    Science.gov (United States)

    Schalenbourg, A; Zografos, L

    2013-01-01

    Colour imaging of fundus tumours has been transformed by the development of digital and confocal scanning laser photography. These advances provide numerous benefits, such as panoramic images, increased contrast, non-contact wide-angle imaging, non-mydriatic photography, and simultaneous angiography. False tumour colour representation can, however, cause serious diagnostic errors. Large choroidal tumours can be totally invisible on angiography. Pseudogrowth can occur because of artefacts caused by different methods of fundus illumination, movement of reference blood vessels, and flattening of Bruch's membrane and sclera when tumour regression occurs. Awareness of these pitfalls should prevent the clinician from misdiagnosing tumours and wrongfully concluding that a tumour has grown. PMID:23238442

  2. Water immersion in neonatal bereavement photography.

    Science.gov (United States)

    Duffey, Heather

    2014-01-01

    Water immersion in neonatal bereavement photography is a new technique intended to enhance the quality of the photographs provided to families following their loss. Water immersion appears to be most helpful following a second trimester fetal demise. This technique can be used by nurses, professional photographers and others in addition to more traditional neonatal bereavement photography. It does not require special skills or equipment and can be implemented in virtually any perinatal setting. The enhanced quality of photographs produced with this method can potentially provide a source of comfort to grieving families. © 2014 AWHONN.

  3. Clinical Photography for Trichology Practice: Tips and Tricks

    OpenAIRE

    Ashique, KT; Kaliyadan, Feroze

    2011-01-01

    Clinical photography of hair disorders is an extension of photography in dermatology practice. Some points should be kept in mind while taking images of the hair and hair bearing areas in view of the reflection of light and the subsequent glare that may spoil the result. For documentation of most conditions of the hair, the same general rules of dermatological photography apply. The correct lighting is the most important aspect of clinical photography in trichology practice and can be achieve...

  4. Satellite Shadow Modeling and Algorithm of Satellite Shadow Parameters for GNSS

    Directory of Open Access Journals (Sweden)

    DU Lan

    2016-11-01

    Full Text Available The satellite shadow parameters can be numerically calculated with high accuracy from the positions of the sun, the earth and the specific satellite. Unfortunately, it is difficult for the numerical calculation to give a general profile of the variations and distributions of these parameters for some certain types of orbital spacecraft. A satellite shadow model was presented based on the spatial view at the altitude of the satellite and the correlative geometry amongst the sun, the earth and the satellite. Firstly, the size and location of the satellite shadow were determined by the semi-major axis of the satellite orbit and the annual motion of the apparent sun, respectively. Secondly, the computing formulae of the satellite shadow parameters were derived, together with the correction formulae for the long-term prediction of the parameters due to oblateness perturbation, etc. Examinations on the three types of orbits for the BeiDou navigation constellation show that the proposed satellite shadow model and its shadow parameters computing formulae can provide a prompt profile of the eclipse parameters for the medium-high altitude circular orbit satellites.

  5. A Photography Primer for Middle School Students and Teachers.

    Science.gov (United States)

    Price, Charles L.

    Project PHOTO provides a format for middle school students to learn about photography with three different types of techniques: sun prints, can cameras, and pinhole cameras. Additional topics and activities include film developing, contact prints and enlarging, history of photography, photographic composition, types of cameras, a photography word…

  6. 75 FR 3862 - Photography in Public Exhibit Space

    Science.gov (United States)

    2010-01-25

    ... RECORDS ADMINISTRATION 36 CFR Part 1280 RIN 3095-AB60 Photography in Public Exhibit Space AGENCY: National... documents accessible and available to the public, and that by prohibiting photography, NARA will make its... from visitors requesting and demanding that NARA eliminate all photography. Comments such as these...

  7. 76 FR 40338 - Marine Mammals; Photography Permit No. 16360

    Science.gov (United States)

    2011-07-08

    ... National Oceanic and Atmospheric Administration Marine Mammals; Photography Permit No. 16360 AGENCY..., Auckland, New Zealand to conduct commercial/educational photography of cetaceans off Hawaii. ADDRESSES: The... request for a permit to conduct commercial/educational photography on 12 cetacean species had been...

  8. Guidelines for Standard Photography in Gross and Clinical Anatomy

    Science.gov (United States)

    Barut, Cagatay; Ertilav, Hakan

    2011-01-01

    Photography has a widespread usage in medicine and anatomy. In this review, authors focused on the usage of photography in gross and clinical anatomy. Photography in gross and clinical anatomy is not only essential for accurate documentation of morphological findings but also important in sharing knowledge and experience. Photographs of cadavers…

  9. 76 FR 27307 - Marine Mammals; Photography Permit Application No. 16360

    Science.gov (United States)

    2011-05-11

    ... National Oceanic and Atmospheric Administration RIN 0648-XA426 Marine Mammals; Photography Permit..., Auckland, New Zealand has applied in due form for a permit to conduct commercial/educational photography of... for photography for educational or commercial purposes involving non-endangered and non-threatened...

  10. Cosmic Ray Sun Shadow in Soudan 2 Underground Muon Flux

    OpenAIRE

    Soudan 2 Collaboration

    1999-01-01

    The absorption of cosmic rays by the sun produces a shadow at the earth. The angular offset and broadening of the shadow are determined by the magnitude and structure of the interplanetary magnetic field (IPMF) in the inner solar system. We report the first measurement of the solar cosmic ray shadow by detection of deep underground muon flux in observations made during the entire ten-year interval 1989 to 1998. The sun shadow varies significantly during this time, with a $3.3\\sigma$ shadow ob...

  11. Ultrasonic detection of calcification in gallstones: "the reverberation shadow".

    Science.gov (United States)

    Parulekar, S G

    1984-03-01

    Observation of reverberations within a gallstone shadow (the "reverberation shadow") resulted in this study. Reverberation shadow was seen in sonograms of 27 patients with gallstones and three patients with milk of calcium bile. Calcification within gallstones was demonstrated by radiography or computed tomography in 22 of the 27 patients with gallstones, associated with the reverberation shadow. Whether the remaining five patients had calcified gallstones remains unknown. This study suggests that the reverberation shadow produced by gallstones indicates the presence of calcification within the gallstones.

  12. SmartShadow models and methods for pervasive computing

    CERN Document Server

    Wu, Zhaohui

    2013-01-01

    SmartShadow: Models and Methods for Pervasive Computing offers a new perspective on pervasive computing with SmartShadow, which is designed to model a user as a personality ""shadow"" and to model pervasive computing environments as user-centric dynamic virtual personal spaces. Just like human beings' shadows in the physical world, it follows people wherever they go, providing them with pervasive services. The model, methods, and software infrastructure for SmartShadow are presented and an application for smart cars is also introduced.  The book can serve as a valuable reference work for resea

  13. Do Elementary Science Methods Textbooks Promote Understanding of Shadows?

    Directory of Open Access Journals (Sweden)

    Lloyd H. Barrow

    2016-02-01

    Full Text Available Elementary science methods textbooks can be an important resource for future elementary teachers of science. Since shadows are a common topic in elementary school and Next Generation Science Standards (NGSS Lead States, 2013. A series of ten shadows concepts were formed into a learning progression by Wizman and Fortus (2007. For this research, ten science methods textbook were read and analyzed about how each of the shadow concepts were addressed. These methods textbooks focused on a limited number of shadow concepts. Consequently, as a future reference, they are very limited in addressing all ten shadow concepts.

  14. Automated detection and removal of cloud shadows on HICO images

    Science.gov (United States)

    Amin, Ruhul; Gould, Richard; Hou, Weilin; Lee, Zhongping; Arnone, Robert

    2011-06-01

    Clouds cause a serious problem for optical satellite sensors. Clouds not only conceal the ground, they also cast shadows, which cause either a reduction or total loss of information in an image, by reducing the illumination falling on the shadowed pixels. Ocean color bio-optical inversion algorithms rely on measurements of remote sensing reflectance (Rrs (λ )) at each pixel. If shadows are not removed properly across a scene, erroneous Rrs (λ) values will be calculated for the shadowed pixels, leading to incorrect retrievals of ocean color products such as chlorophyll. The cloud shadow issue becomes significant especially for high-resolution sensors such as the Hyperspectral Imager for the Coastal Ocean (HICO). On the other hand, the contrast of pixels in and outside a shadow provides opportunities to remove atmospheric contributions for ocean color remote sensing. Although identifying cloud is relatively straightforward using simple brightness thresholds, identifying their shadows especially over water is quite challenging because the brightness of the shadows is very close to the brightness of neighboring sunny regions especially in deep waters. In this study, we present automated procedures for our recently proposed cloud shadow detection technique called the Cloud Shadow Algorithm (CSA) and Lee et al. (2007) cloud and shadow atmospheric correction algorithm. We apply both automated procedures to HICO imagery and show examples of the results.

  15. Exposing image forgery by detecting consistency of shadow.

    Science.gov (United States)

    Ke, Yongzhen; Qin, Fan; Min, Weidong; Zhang, Guiling

    2014-01-01

    We propose two tampered image detection methods based on consistency of shadow. The first method is based on texture consistency of shadow for the first kind of splicing image, in which the shadow as well as main body is copied and pasted from another image. The suspicious region including shadow and nonshadow is first selected. Then texture features of the shadow region and the nonshadow region are extracted. Last, correlation function is used to measure the similarity of the two texture features. By comparing the similarity, we can judge whether the image is tampered. Due to the failure in detecting the second kind of splicing image, in which main body, its shadow, and surrounding regions are copied and pasted from another image, another method based on strength of light source of shadows is proposed. The two suspicious shadow regions are first selected. Then an efficient method is used to estimate the strength of light source of shadow. Last, the similarity of strength of light source of two shadows is measured by correlation function. By combining the two methods, we can detect forged image with shadows. Experimental results demonstrate that the proposed methods are effective despite using simplified model compared with the existing methods.

  16. Exposing Image Forgery by Detecting Consistency of Shadow

    Directory of Open Access Journals (Sweden)

    Yongzhen Ke

    2014-01-01

    Full Text Available We propose two tampered image detection methods based on consistency of shadow. The first method is based on texture consistency of shadow for the first kind of splicing image, in which the shadow as well as main body is copied and pasted from another image. The suspicious region including shadow and nonshadow is first selected. Then texture features of the shadow region and the nonshadow region are extracted. Last, correlation function is used to measure the similarity of the two texture features. By comparing the similarity, we can judge whether the image is tampered. Due to the failure in detecting the second kind of splicing image, in which main body, its shadow, and surrounding regions are copied and pasted from another image, another method based on strength of light source of shadows is proposed. The two suspicious shadow regions are first selected. Then an efficient method is used to estimate the strength of light source of shadow. Last, the similarity of strength of light source of two shadows is measured by correlation function. By combining the two methods, we can detect forged image with shadows. Experimental results demonstrate that the proposed methods are effective despite using simplified model compared with the existing methods.

  17. Politics, Time and Space in the Era of Shadow Banking

    DEFF Research Database (Denmark)

    Bryan, Dick; Rafferty, Michael; Wigan, Duncan

    2016-01-01

    In the wake of the Global Financial Crisis, there has been an understandable focus on the financial fragility and contagion aspects of shadow banking. This article argues that shadow banking is important for another set of reasons. It has been well established that shadow banking permits the tran......In the wake of the Global Financial Crisis, there has been an understandable focus on the financial fragility and contagion aspects of shadow banking. This article argues that shadow banking is important for another set of reasons. It has been well established that shadow banking permits...... challenging earlier spatio-temporal concepts of finance, and the regulatory/jurisdictional order built on them. The article suggests that the longer term significance of shadow banking may not just be its role in financial crisis, or even tax and regulatory arbitrage, but that it was here that innovative...

  18. ASO EBI: FASHIONING SELF THROUGH PHOTOGRAPHY AND ...

    African Journals Online (AJOL)

    Precious

    standards of beauty, dressing and poses. Photography thus actively speaks to viewers about their desires and aspirations and appears to offer solution to perceived problems of self- representation, self-actualization and self-image. Aso Ebi Photographic Poses. By pointing out stylistic conventions in aso ebi photographic.

  19. Image Processing in Amateur Astro-Photography

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 15; Issue 2. Image Processing in Amateur Astro-Photography. Anurag Garg. Classroom Volume 15 Issue 2 February 2010 pp 170-175. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/015/02/0170-0175 ...

  20. Still Photography: Can It Provide Program Portrayal?

    Science.gov (United States)

    Templin, Patricia Scheyer

    Still photography can help portray educational programs for description and evaluation. There may, however, be problems with this method. Photographic images idealize the subjects; the framing is arbitrary, lends importance and veracity at the same time it levels an event to a very thin slice of reality. The evaluator-photographer may have…

  1. Office photography from the surgical viewpoint.

    Science.gov (United States)

    Sebben, J E

    1983-09-01

    This article reviews the special considerations necessary for adequate photography in a surgical practice. The selection of film, camera, lens, and flash is discussed. Major emphasis is on proper framing and composition of the subject matter. Recommendations are made concerning consent forms and filing of slides.

  2. UV Photography Shows Hidden Sun Damage

    Science.gov (United States)

    ... var c = 0; c UV photography shows hidden sun damage A UV photograph gives us a safe way to see how the sun damages our skin. In the UV photos that ... on the right, you can see what hidden sun damage looks like. Compare these UV photos with ...

  3. Photography of Coral Reefs from ISS

    Science.gov (United States)

    Robinson, Julie A.

    2009-01-01

    This viewgraph presentation reviews the uses of photography from the International Space Station (ISS) in studying Earth's coral reefs. The photographs include reefs in various oceans . The photographs have uses for science in assisting NASA mapping initiatives, distribution worldwide through ReefBase, and by biologist in the field.

  4. Using Photography to Foster Intergenerational Understanding

    Science.gov (United States)

    Fearnside, Lee; Bereza, Matthew; McConn, Gabriel

    2015-01-01

    This study examines how a visual art academic experience might help to reduce anxiety about interactions with the elderly, mitigate fears over aging, encourage more interactions with older people and improve visual literacy skills. University students in an introductory digital photography course interpreted conversations with residents of a local…

  5. Time sequence photography of Roosters Comb

    Science.gov (United States)

    The importance of understanding natural landscape changes is key in properly determining rangeland ecology. Time sequence photography allows a landscape snapshot to be documented and enables the ability to compare natural changes overtime. Photographs of Roosters Comb were taken from the same vantag...

  6. "Transformative Looks": Practicing Citizenship through Photography

    Science.gov (United States)

    Pereira, Sónia; Maiztegui-Oñate, Concha; Mata-Codesal, Diana

    2016-01-01

    Purpose: The article discusses the meanings of citizenship and citizenship education when formal citizenship is restricted by exploring the potential of photography education and practice as a tool that promotes the exercise of citizenship in the context of non-formal critical adult education. By doing it, this text aims to enhance our…

  7. Public Reporting: Illumination or Shadows?

    Directory of Open Access Journals (Sweden)

    LE Nicolle

    2006-01-01

    Full Text Available The infection control communities in Britain and the United States (US are experiencing an extraordinary conceptual shift with legislated mandatory reporting of hospital infections. In Britain, this shift began in 2001 with methicillin-resistant Staphylococcus aureus (MRSA bacteremia episodes (1, which are reported to the National Health Service and are publically available on a Health Protection Agency Web site. In the US, the impetus for public reporting of infection rates has come from consumer groups (2. These organizations have bypassed health care organizations and public health and other practitioners, and have addressed their demands to state legislatures. At least eight states have now passed and several more are considering legislation to mandate reporting. The process has been rancorous and, at least initially, vigorously opposed by health care organizations and infection control practitioners.

  8. Fuzzy split and merge for shadow detection

    Directory of Open Access Journals (Sweden)

    Remya K. Sasi

    2015-03-01

    Full Text Available Presence of shadow in an image often causes problems in computer vision applications such as object recognition and image segmentation. This paper proposes a method to detect the shadow from a single image using fuzzy split and merge approach. Split and merge is a classical algorithm used in image segmentation. Predicate function in the classical approach is replaced by a Fuzzy predicate in the proposed approach. The method follows a top down approach of recursively splitting an image into homogeneous quadtree blocks, followed by a bottom up approach by merging adjacent unique regions. The method has been compared with previous approaches and found to be better in performance in terms of accuracy.

  9. Fading and Shadowing in Wireless Systems

    CERN Document Server

    Shankar, P Mohana

    2012-01-01

    In recent decades, growth in the field of wireless communications has led to an exponential rise in the number of journals catering to the research community. Still unmet, however, is the need to fully and comprehensively understand the effects of channel degradation brought on by the statistical fluctuations in the channel. These fluctuations mainly manifest as variations in signal power observed in the channel generally modeled using a variety of probability distributions, both in straight forms as well as in compound forms. While the former might explain some of the effects, it is the latter, namely, the compound models, which incorporate both short term and long term power fluctuations in the channel, explain the much more complex nature of the signals in these channels. Fading and Shadowing in Wireless Systems offers a pedagogical approach to the topic, with insight into the modeling and analysis of fading and shadowing. Beginning with statistical background and digital communications, the book is formul...

  10. LIGHT, SHADOW AND WIND IN BUILDING DESIGN.

    OpenAIRE

    Katyarmal, Preeti P

    2008-01-01

    Design is about understanding a space. It is about integration of light and air in building design. It is about light, shadow, reflection. It is about wind, its movement and escape. Through designing this project I was able to explore how sun, wind and light can be used effectively in a building design, in my project, in an office environment. The fire, the Light; the energy is the inspiration behind the origin of Architecture. Energy brings architecture into the world of...

  11. Nebkha flow dynamics and shadow dune formation

    Science.gov (United States)

    Hesp, Patrick A.; Smyth, Thomas A. G.

    2017-04-01

    In this study, wind flow is simulated via CFD over five 'nebkha' dune forms that range in shape from a cone, to a hemisphere (approximately) and to a dome in order to examine the structure of the wake zone formed downwind and the effect on the leeward flow separation zone and shadow dune formation. Dune height was fixed at 0.5 m while the nebkha diameter increased in 0.25 m increments from 0.5 m to 1.5 m and aspect ratio (h/D) from 1.0 to 0.3. The mean flow comprises an upwind region of reduced velocity which expands as nebkha width increases, high velocity marginal wings, and paired counter-rotating reversing vortices leeward of the nebkha. The point at which flow separation occurs moves further downwind as the nebkha diameter increases. The core regions of the reversing vortices are situated further downwind behind the smaller nebkha than in the case of the larger nebkha. These factors in combination allow for higher velocity perturbations (TKE) and narrower wake behind the smaller nebkha, and the suppression of downwind wake development in the case of the increasingly larger nebkha. Shadow dune length increases as nebkha width increases for lower incident velocity flow and is barely affected by nebkha width at higher flows. The extent of the leeward separation or wake zone, and hence shadow dune length, more strongly varies as a function of wind velocity.

  12. Infant Perception of Incongruent Shapes in Cast Shadows

    Directory of Open Access Journals (Sweden)

    Kazuki Sato

    2015-04-01

    Full Text Available A cast shadow occurs when an object blocks the light from an illumination and projects a dark region onto a surface. Previous studies have reported that adults are slower to identify an object when the object has an incongruent cast shadow than when it has a congruent cast shadow (Castiello, 2001. Here, we used the familiarization-novelty preference procedure to examine whether 5- to 8-month-old infants could detect the relationship between object shapes and cast shadows. In Experiment 1, we examined the infants' ability to detect incongruency between objects and cast shadows. Results showed that 7- to 8-month olds could detect incongruence between the object shapes and the cast shadows, whereas 5- to 6-month olds did not. Yet, our control experiment showed that infants could not detect this incongruence from stimuli in which a white outline had been added to the original cast shadow to decrease the possibility of it being perceived as a cast shadow (Experiment 2. The results of these experiments demonstrate that 7- to 8-month olds responded to the congruence of cast shadows and to consistent contrast polarity between the cast shadow and its background.

  13. Best practice in bereavement photography after perinatal death: qualitative analysis with 104 parents.

    Science.gov (United States)

    Blood, Cybele; Cacciatore, Joanne

    2014-01-01

    Postmortem memento photography has emerged in Western hospitals as part of compassionate bereavement care for parents facing perinatal death. Many parents endorse this psychosocial intervention, yet implementation varies greatly and little research on parents' specific needs guides health care professionals. Parents are in crisis and vulnerable after the death of their child, thus best practice is crucial. This study contributes 104 parents' experiences and opinions toward the understanding of best practice in perinatal bereavement photography. Parents who experienced the perinatal death of their child were recruited from U.S.-based bereavement organizations and social media sites. Volunteers completed an anonymous internet survey with open- and closed-ended questions. Direct recommendations and pertinent statements regarding the process of postmortem photography were analyzed for thematic content in keeping with conventional content analysis. Recurrent themes and sub-themes were counted to identify response patterns. Of 93 parents with pictures, 92 endorsed them. Of 11 without pictures, nine wanted them. Parents made a variety of recommendations regarding appropriate psychosocial support, the consent process, obstacles to photography, logistics of photography, and material aspects of photographs themselves. Overall, parents wanted many pictures and much variety. Some wanted professional photography while others wanted support for taking their own pictures. Parents wanted guidance from staff who respected their particular needs. Many said decisions were difficult during their crisis. Parents who were initially resistant expressed current appreciation for pictures or expressed regret that they had not participated. Parents recommended that professionals strongly encourage parents to create memento photos despite parents' initial reservations. Persistent cultural reasons against photography emerged in one case. Quotes by parents illuminate themes and enable

  14. Change detection using 75-year aerial photo and satellite data sets, inexpensive means to obtain 6 cm resolution data, and developing opportunities for community-oriented remote sensing through photography

    Science.gov (United States)

    Some governmental research sites have been in existence for as many as 100 years with ground photography used for documentation starting in the early 1900s(e.g., at the USDA Jornada Experimental Range(JER)(783 km2) in south central New Mexico) If ground photography is properly documented when acquir...

  15. Shadow bands during the total solar eclipse of 3 November 1994.

    Science.gov (United States)

    Jones, B. W.

    1996-08-01

    The author recorded shadow bands just before and just after the total phase of the solar eclipse of 3 November 1994. The recordings were made using two broad-band silicon photodiodes separated by 100 mm. They were mounted on a plate that faced the eclipsed Sun, which was at an altitude of 32.4° as seen from the observing site 4500 m above sea level between Putre and Lake Chungara in northern Chile. The irradiance fluctuations associated with the shadow bands were around 0.008 W m-2 rms on a background of about 2-8 W m-2. The cross-correlation function indicates that the shadow bands were moving at a speed of about 1.8 m s-1 perpendicular to their extent. The power spectral density functions are in accord with the shadow band theory of Codona (1986). The author carried out a similar experiment in Baja California during the eclipse of 11 July 1991. In spite of the considerable differences between the two circumstances, the results on the two occasions are broadly similar.

  16. Truth and beauty in contemporary urban photography

    Directory of Open Access Journals (Sweden)

    Daniele Colistra

    2014-05-01

    Full Text Available Does city still need photography? Or does it show itself more effectively through other forms of communication? The question brings us back almost two hundred years ago, at the time of the spread of the first daguerreotypes, when the query was: Does city still need painting? The question raises several other issues - truth and beauty, analogical and digital, truth and photo editing - that this essay examines by comparing some images. We are convinced that “the more we can speak of a picture, the more unlikely it is to speak of photography” (R. Barthes. The essay describes the work of some artists/photographers who have addressed the issue of urban photography. Works in which the figurative and visionary component is based on the interaction of traditional shooting techniques and processes of digital post-production.

  17. Clustered deep shadow maps for integrated polyhedral and volume rendering

    KAUST Repository

    Bornik, Alexander

    2012-01-01

    This paper presents a hardware-accelerated approach for shadow computation in scenes containing both complex volumetric objects and polyhedral models. Our system is the first hardware accelerated complete implementation of deep shadow maps, which unifies the computation of volumetric and geometric shadows. Up to now such unified computation was limited to software-only rendering . Previous hardware accelerated techniques can handle only geometric or only volumetric scenes - both resulting in the loss of important properties of the original concept. Our approach supports interactive rendering of polyhedrally bounded volumetric objects on the GPU based on ray casting. The ray casting can be conveniently used for both the shadow map computation and the rendering. We show how anti-aliased high-quality shadows are feasible in scenes composed of multiple overlapping translucent objects, and how sparse scenes can be handled efficiently using clustered deep shadow maps. © 2012 Springer-Verlag.

  18. The shadow of black holes an analytic description

    CERN Document Server

    Grenzebach, Arne

    2016-01-01

    This book introduces an analytic method to describe the shadow of black holes. As an introduction, it presents a survey of the attempts to observe the shadow of galactic black holes. Based on a detailed discussion of the Plebański–Demiański class of space-times, the book derives analytical formulas for the photon regions and for the boundary curve of the shadow as seen by an observer in the domain of outer communication. It also analyzes how the shadow depends on the motion of the observer. For all cases, the photon regions and shadows are visualized for various values of the parameters. Finally, it considers how the analytical formulas can be used for calculating the horizontal and vertical angular diameters of the shadow, and estimates values for the black holes at the centers of our Galaxy near Sgr A* and of the neighboring galaxy M87.

  19. PRECONDITIONS AND DETERMINING CAUSES OF THE SHADOW ECONOMY IN UKRAINE

    Directory of Open Access Journals (Sweden)

    Z. Varnalii

    2014-03-01

    Full Text Available The article analyzes the main processes that led to the high level of the economy shadowing. The historical aspects of the formation of the shadow economy in Ukraine are highlighted. The socio-economic aspects of the shadow economy of Ukraine causality are discussed. The theoretical contribution of foreign and domestic researchers on the preconditions of formation of the shadow economy in transition economies is studied. Theoretical perspective on the factors of the shadowing processes in the economy of Ukraine from the standpoint of modern scientific researches is analyzed. The paper also provides scientific vectors for further development of researches aimed at studying the causes and preconditions of the shadow economy.

  20. The phenomenon of motion in photography

    OpenAIRE

    Hižová, Katarína

    2015-01-01

    The purpose of this thesis is to explore distinct techniques of capturing motion in still and animated photography. It also concentrates on describing the history, types and use of stop motion animation in the field of movie production, music, computer games and marketing communication. Practical part deals with the production process of short stop motion animations and its implementation to the communication strategy of a bachelor project called Kapustové Zelí.

  1. Photography as a Witness of Theatre

    OpenAIRE

    Dondero, Maria Giulia

    2008-01-01

    My paper investigates the meeting of theatre and photography in ‘theatre photography’. Recognizing that both art forms can determine theoretical and philosophical views on representation and self-representation, I aim to compare their visual strategies and the way they construct point of view. In the process several questions are raised: do qualities of photographs belong to objects photographed or to photographs themselves? How important is the object that ‘triggers’ the view? Should the the...

  2. Promoting Positive Affect through Smartphone Photography.

    OpenAIRE

    Chen, Y; Mark, G.; Ali, S

    2016-01-01

    Background With the increasing quality of smartphone cameras, taking photos has become ubiquitous. This paper investigates how smartphone photography can be leveraged to help individuals increase their positive affect. Methods Applying findings from positive psychology, we designed and conducted a 4-week study with 41 participants. Participants were instructed to take one photo every day in one of the following three conditions: a selfie photo with a smiling expression, a photo of something t...

  3. Benchmarking clinical photography services in the NHS.

    Science.gov (United States)

    Arbon, Giles

    2015-01-01

    Benchmarking is used in services across the National Health Service (NHS) using various benchmarking programs. Clinical photography services do not have a program in place and services have to rely on ad hoc surveys of other services. A trial benchmarking exercise was undertaken with 13 services in NHS Trusts. This highlights valuable data and comparisons that can be used to benchmark and improve services throughout the profession.

  4. Smartphone photography in oral and maxillofacial surgery.

    Science.gov (United States)

    Jamil, F

    2016-01-01

    An increasing number of staff in oral and maxillofacial surgery (OMFS) departments take clinical photographs with their personal phones. We report the results of a survey on the use of smartphone photography in OMFS departments in the United Kingdom, and highlight the guidelines that govern their use and the associated ethical and medicolegal implications. Copyright © 2015 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  5. Corruption and the Shadow Economy: An Empirical Analysis

    OpenAIRE

    Dreher, Axel; Friedrich G. Schneider

    2006-01-01

    This paper analyzes the influence of the shadow economy on corruption and vice versa. We hypothesize that corruption and the shadow economy are substitutes in high income countries while they are complements in low income countries. The hypotheses are tested for a cross-section of 98 countries. Our results show that there is no robust relationship between corruption and the size of the shadow economy when perceptions-based indices of corruption are used. Employing an index of corruption based...

  6. Shadow Segmentation and Augmentation Using á-overlay Models that Account for Penumbra

    DEFF Research Database (Denmark)

    Nielsen, Michael; Madsen, Claus B.

    2006-01-01

    that an augmented virtual object can cast an exact shadow. The penumbras (half-shadows) must be taken into account so that we can model the soft shadows.We hope to achieve this by modelling the shadow regions (umbra and penumbra alike) with a transparent overlay. This paper reviews the state-of-the-art shadow...

  7. Automatic Shadow Detection and Removal from a Single Image.

    Science.gov (United States)

    Khan, Salman H; Bennamoun, Mohammed; Sohel, Ferdous; Togneri, Roberto

    2016-03-01

    We present a framework to automatically detect and remove shadows in real world scenes from a single image. Previous works on shadow detection put a lot of effort in designing shadow variant and invariant hand-crafted features. In contrast, our framework automatically learns the most relevant features in a supervised manner using multiple convolutional deep neural networks (ConvNets). The features are learned at the super-pixel level and along the dominant boundaries in the image. The predicted posteriors based on the learned features are fed to a conditional random field model to generate smooth shadow masks. Using the detected shadow masks, we propose a Bayesian formulation to accurately extract shadow matte and subsequently remove shadows. The Bayesian formulation is based on a novel model which accurately models the shadow generation process in the umbra and penumbra regions. The model parameters are efficiently estimated using an iterative optimization procedure. Our proposed framework consistently performed better than the state-of-the-art on all major shadow databases collected under a variety of conditions.

  8. Interactive removal and ground truth for difficult shadow scenes

    OpenAIRE

    Gong, Han; Cosker, Darren

    2016-01-01

    A user-centric method for fast, interactive, robust, and high-quality shadow removal is presented. Our algorithm can perform detection and removal in a range of difficult cases, such as highly textured and colored shadows. To perform detection, an on-the-fly learning approach is adopted guided by two rough user inputs for the pixels of the shadow and the lit area. After detection, shadow removal is performed by registering the penumbra to a normalized frame, which allows us efficient estimati...

  9. Photography/Monument. History of Childhood and Post-mortem Photography

    Directory of Open Access Journals (Sweden)

    José María Borras Llop

    2010-04-01

    Full Text Available This article presents an argument in favor of the full integration of photographic images within historical analysis. From this perspective, I have approached the history of childhood, the field of research which I have concentrated on, in recent years. My focus is on two major topics: images of child labour and representations of infant mortality. The article is divided into two main sections. The first succinctly lays out the main arguments and opinions concerning the interpretation of photography from the point of view of photographers, historians of photography, photography and art critics, image theorists, anthropologists and social and cultural historians. The second section focuses on the analysis of specific cases, without seeking to present it as a model.

  10. A guideline to medical photography: a perspective on digital photography in an orthopaedic setting.

    Science.gov (United States)

    de Meijer, P P G; Karlsson, J; LaPrade, R F; Verhaar, J A N; Wijdicks, C A

    2012-12-01

    Quality photographs are essential for clinical documentation, research, and publication in scientific journals and teaching. Oftentimes, non-ideal lighting and a sterile environment restrict the medical photographer, resulting in lower-quality photographs. This article aims to provide a clear and comprehensible guideline for medical photography in an orthopaedic setting. This article is based on extensive photographic involvement in operating and laboratory settings, in close collaboration with medical professionals from the Steadman Clinic (Vail, Colorado, USA), Gothenburg University (Göteborg, Sweden) and Erasmus MC (Rotterdam, the Netherlands). Background literature was searched through Google Scholar and PubMed. Three relevant journal articles, and one book on medical photography, were used to write this paper. Seventeen Internet articles were used for background information. A relevant, up-to-date and comprehensive guideline to medical photography for medical professionals, with or without photographic experience, is provided. Expert opinion, Level V.

  11. Clinical photography for periorbital and facial aesthetic practice

    Directory of Open Access Journals (Sweden)

    Akshay Gopinathan Nair

    2016-01-01

    Full Text Available External cutaneous photography involves photographic documentation, which helps in treatment planning, documentation of facial features, teaching, publishing and pre- and post-procedural comparisons. The key is not simply documenting, but documenting it the right way and ensuring that photography is standardised and reproducible. In this review, basic photography techniques, standardised and reproducible angles such as frontal, oblique and lateral views and specific photographic angles for conditions such as facial rejuvenation are discussed. Use of photography accessories and a few tips on how to click good photographs in the examination room and how to achieve consistency in standardised photography are also presented. External photography in ophthalmic and facial plastic surgery like any other speciality too has standardised guidelines. Even small variations cause a drastic change in the photos and it's clinical and research value. Unless stringent criteria are met, the photographs lose their relevance and impact.

  12. Clinical Photography for Periorbital and Facial Aesthetic Practice.

    Science.gov (United States)

    Nair, Akshay Gopinathan; Santhanam, Aparna

    2016-01-01

    External cutaneous photography involves photographic documentation, which helps in treatment planning, documentation of facial features, teaching, publishing and pre- and post-procedural comparisons. The key is not simply documenting, but documenting it the right way and ensuring that photography is standardised and reproducible. In this review, basic photography techniques, standardised and reproducible angles such as frontal, oblique and lateral views and specific photographic angles for conditions such as facial rejuvenation are discussed. Use of photography accessories and a few tips on how to click good photographs in the examination room and how to achieve consistency in standardised photography are also presented. External photography in ophthalmic and facial plastic surgery like any other speciality too has standardised guidelines. Even small variations cause a drastic change in the photos and it's clinical and research value. Unless stringent criteria are met, the photographs lose their relevance and impact.

  13. Clinical Photography for Periorbital and Facial Aesthetic Practice

    Science.gov (United States)

    Nair, Akshay Gopinathan; Santhanam, Aparna

    2016-01-01

    External cutaneous photography involves photographic documentation, which helps in treatment planning, documentation of facial features, teaching, publishing and pre- and post-procedural comparisons. The key is not simply documenting, but documenting it the right way and ensuring that photography is standardised and reproducible. In this review, basic photography techniques, standardised and reproducible angles such as frontal, oblique and lateral views and specific photographic angles for conditions such as facial rejuvenation are discussed. Use of photography accessories and a few tips on how to click good photographs in the examination room and how to achieve consistency in standardised photography are also presented. External photography in ophthalmic and facial plastic surgery like any other speciality too has standardised guidelines. Even small variations cause a drastic change in the photos and it's clinical and research value. Unless stringent criteria are met, the photographs lose their relevance and impact. PMID:27398013

  14. History and current use of clinical photography in orthodontics.

    Science.gov (United States)

    Galante, Donna L

    2009-03-01

    The history of dentistry and photography began in 1840 when the first dental school was opened, and the world's first photographic gallery was opened and operated by a dentist turned photographer. Since that time, photography and dentistry have been partners as photography has become an integral part of a patient's record and treatment plan. The specialty of orthodontics has led the way in this model of recording patient data.

  15. Clinical photography for periorbital and facial aesthetic practice

    OpenAIRE

    Akshay Gopinathan Nair; Aparna Santhanam

    2016-01-01

    External cutaneous photography involves photographic documentation, which helps in treatment planning, documentation of facial features, teaching, publishing and pre- and post-procedural comparisons. The key is not simply documenting, but documenting it the right way and ensuring that photography is standardised and reproducible. In this review, basic photography techniques, standardised and reproducible angles such as frontal, oblique and lateral views and specific photographic angles for co...

  16. Face Recognition and the Emergence of Smart Photography

    OpenAIRE

    Kember, Sarah

    2014-01-01

    This article examines face recognition as a key instance of the emergence of smart photography. Smart photography, drawing on Artificial Intelligence (AI) and Ambient Intelligence (AmI) manifests a ‘habit of mind’ (Karen Barad), or a way of thinking that is humanist in so far as it is predicated on human and machine autonomy, and representationalist in its quest for unmediated objects-in-themselves. Faces are among the objects that smart photography seeks (autonomously) to represent. By exami...

  17. The cultural institutionalization of photography in France: a brief history

    OpenAIRE

    Yacavone, Kathrin

    2014-01-01

    This article provides a historical overview of the cultural institutionalization of photography in France, with a particular focus on the pioneering initiatives of individual photography enthusiasts throughout the 1970s to promote photographic culture. These efforts were roughly simultaneous with changes in acquisition and exhibition practices on the part of fine art museums and collections with respect to photography, in response to an increasing world-wide recognition of its status as an ar...

  18. Polarized light photography in the evaluation of photoaging.

    Science.gov (United States)

    Muccini, J A; Kollias, N; Phillips, S B; Anderson, R R; Sober, A J; Stiller, M J; Drake, L A

    1995-11-01

    The clinical characteristics of photodamaged skin, such as coarse and fine wrinkling, sallowness, hyperpigmentation, tactile roughness, laxity, and erythema, are not accurately evaluable from photographic records. The purpose of this study was to develop accurate and reproducible photographic techniques that generate an evaluable record of the characteristics of photodamaged skin. The method used involved illumination and photography through polarizing filters (polarized light photography). Polarized light photography generates images that selectively enhance either the surface features or the subsurface features of the skin, providing an accurate and evaluable record for evaluation of photodamaged skin. Polarized light photography, when coupled with precise framing and mapping, yields an accurate and evaluable record of photodamaged skin.

  19. [Scheimpflug photography for the examination of phakic intraocular lenses].

    Science.gov (United States)

    Baumeister, M

    2014-10-01

    High myopia phakic intraocular lenses (IOL) have become an established means of surgical correction for high ametropia. Scheimpflug photography is one of the methods which are frequently applied for postoperative examination of the implants. Results from published studies employing Scheimpflug photography for examination of anterior chamber angle-fixated, iris-fixated and sulcus-fixated phakic IOLs were evaluated. In several published studies Scheimpflug photography was used to examine the position of the implant and opacification of the crystalline lens. The results provided valuable evidence for the improvement of phakic IOL design. Scheimpflug photography offers an easy to use, rapid non-contact examination of phakic IOLs.

  20. The shadow price of fossil groundwater

    Science.gov (United States)

    Bierkens, Marc F. P.; Reinhard, Stijn; de Bruijn, Jens A.; Wada, Yoshihide

    2017-04-01

    The expansion of irrigated agriculture into areas with limited precipitation and surface water during the growing season has greatly increased the use of fossil groundwater (Wada et al., 2012). As a result, the depletion rate of fossil groundwater resources has shown an increasing rate during the last decades (Wada et al, 2010; Konikow, 2011; Wada et al., 2012; De Graaf et al. 2015; Ritchy et al., 2015). Although water pricing has been used extensively to stimulate efficient application of water to create maximum value (e.g. Medellín-Azuara et al., 2012; Rinaudo et al., 2012; Dinar et al., 2015), it does not preclude the use of non-renewable water resources. Here, we use a global hydrological model and historical crop production and price data to assess the shadow price of non-renewable or fossil groundwater applied to major crops in countries that use large quantities of fossil groundwater. Our results show that shadow prices for many crops are very low, indicating economically inefficient or even wasteful use of fossil groundwater resources. Using India as an example, we show that small changes in the crop mix could lead to large reductions in fossil groundwater use or alternatively, create additional financial means to invest in water saving technologies. Our study thus provides a hydro-economic basis to further the sustainable use of finite groundwater resources.

  1. Shadow edge detection using geometric and photometric features

    NARCIS (Netherlands)

    Gijsenij, A.; Gevers, T.

    2009-01-01

    The detection of shadow and shading edges is a first step towards reducing the imaging effects that are caused by interactions of the light source with surfaces that are in the scene. As most of the algorithms for shadow edge detection use photometric information, geometric information have been

  2. Shadows of Einstein–dilaton–Gauss–Bonnet black holes

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, Pedro V.P., E-mail: pintodacunha@tecnico.ulisboa.pt [Departamento de Física da Universidade de Aveiro and Centre for Research and Development in Mathematics and Applications (CIDMA), Campus de Santiago, 3810-183 Aveiro (Portugal); CENTRA, Departamento de Física, Instituto Superior Técnico, Universidade de Lisboa, Avenida Rovisco Pais 1, 1049, Lisboa (Portugal); Herdeiro, Carlos A.R., E-mail: herdeiro@ua.pt [Departamento de Física da Universidade de Aveiro and Centre for Research and Development in Mathematics and Applications (CIDMA), Campus de Santiago, 3810-183 Aveiro (Portugal); Kleihaus, Burkhard, E-mail: b.kleihaus@uni-oldenburg.de [Institute of Physics, University of Oldenburg, Oldenburg, 26111 (Germany); Kunz, Jutta, E-mail: jutta.kunz@uni-oldenburg.de [Institute of Physics, University of Oldenburg, Oldenburg, 26111 (Germany); Radu, Eugen, E-mail: eugen.radu@ua.pt [Departamento de Física da Universidade de Aveiro and Centre for Research and Development in Mathematics and Applications (CIDMA), Campus de Santiago, 3810-183 Aveiro (Portugal)

    2017-05-10

    We study the shadows of the fully non-linear, asymptotically flat Einstein–dilaton–Gauss–Bonnet (EdGB) black holes (BHs), for both static and rotating solutions. We find that, in all cases, these shadows are smaller than for comparable Kerr BHs, i.e. with the same total mass and angular momentum under similar observation conditions. In order to compare both cases we provide quantitative shadow parameters, observing in particular that the differences in the shadows mean radii are never larger than the percent level. Therefore, generically, EdGB BHs cannot be excluded by (near future) shadow observations alone. On the theoretical side, we find no clear signature of some exotic features of EdGB BHs on the corresponding shadows, such as the regions of negative (Komar, say) energy density outside the horizon. We speculate that this is due to the fact that the Komar energy interior to the light rings (or more precisely, the surfaces of constant radial coordinate that intersect the light rings in the equatorial plane) is always smaller than the ADM mass, and consequently the corresponding shadows are smaller than those of comparable Kerr BHs. The analysis herein provides a clear example that it is the light ring impact parameter, rather than its “size”, that determines a BH shadow.

  3. Shading and shadowing on Canaletto's Piazza San Marco

    NARCIS (Netherlands)

    Wijntjes, M.W.A.; De Ridder, H.

    2014-01-01

    Whereas the 17th century painter Canaletto was a master in linear perspective of the architectural elements, he seems to have had considerable difficulty with linear perspective of shadows. A common trick to avoid shadow perspective problems is to set the (solar) illumination direction parallel to

  4. Safety of iPhone retinal photography.

    Science.gov (United States)

    Hong, Sheng Chiong; Wynn-Williams, Giles; Wilson, Graham

    2017-04-01

    With the advancement in mobile technology, smartphone retinal photography is becoming a popular practice. However, there is limited information about the safety of the latest smartphones used for retinal photography. This study aims to determine the photobiological risk of iPhone 6 and iPhone 6 plus when used in conjunction with a 20Diopter condensing lens for retinal photography. iPhone 6 and iPhone 6 plus (Apple, Cupertino, CA) were used in this study. The geometrical setup of the study was similar to the indirect ophthalmoscopy technique. The phone was set up at one end of the bench with its flash turned on at maximal brightness; a 20 Dioptre lens was placed 15 cm away from the phone. The light that passes through the lens was measured with a spectroradiometer and an illuminance probe at the other end to determine the spectral profile, spatial irradiance, radiant power emitted by the phone's flash. Trigonometric and lens formula were applied to determine the field of view and retinal surface in order to determine the weighted retinal irradiance and weighted retinal radiant exposure. Taking ocular transmission and the distribution of the beam's spatial irradiance into account, the weighted retinal irradiance is 1.40 mW/cm 2 and the weighted retinal radiant exposure is 56.25 mJ/cm 2 . The peak weighted foveal irradiance is 1.61 mW/cm 2 . Our study concluded that the photobiological risk posed by iPhone 6 indirect ophthalmoscopy was at least 1 order of magnitude below the safety limits set by the ISO15004-2.2.

  5. The Desire to Understand and Photography

    OpenAIRE

    Darragon, Eric

    2012-01-01

    Photography is part and parcel of the history of Surrealism, and a far-reaching and active part of that movement. In choosing a provocative title–L’Image au service de la révolution–for his collection of essays, Michel Poivert’s intent was to show that, far from being an accompaniment to writing and publications, the photographic image operated as a way of thinking necessary for that analytical process called Surrealism at the service of revolution. To grasp the phenomenon, it had to be obser...

  6. Integral photography capture and electronic holography display

    Science.gov (United States)

    Ichihashi, Yasuyuki; Yamamoto, Kenji

    2014-06-01

    This paper describes electronic holography output of three-dimensional (3D) video with integral photography as input. A real-time 3D image reconstruction system was implemented by using a 4K (3840×2160) resolution IP camera to capture 3D images and converting them to 8K (7680×4320) resolution holograms. Multiple graphics processing units (GPUs) were used to create 8K holograms from 4K IP images. In addition, higher resolution holograms were created to successfully reconstruct live-scene video having a diagonal size of 6 cm using a large electronic holography display.

  7. Asphalted Road Temperature Variations Due to Wind Turbine Cast Shadows

    Directory of Open Access Journals (Sweden)

    Jonay Toledo

    2009-11-01

    Full Text Available The contribution of this paper is a technique that in certain circumstances allows one to avoid the removal of dynamic shadows in the visible spectrum making use of images in the infrared spectrum. This technique emerged from a real problem concerning the autonomous navigation of a vehicle in a wind farm. In this environment, the dynamic shadows cast by the wind turbines’ blades make it necessary to include a shadows removal stage in the preprocessing of the visible spectrum images in order to avoid the shadows being misclassified as obstacles. In the thermal images, dynamic shadows completely disappear, something that does not always occur in the visible spectrum, even when the preprocessing is executed. Thus, a fusion on thermal and visible bands is performed.

  8. USGS Southwest Repeat Photography Collection: Kanab Creek, southern Utah and northern Arizona, 1872-2010

    Data.gov (United States)

    Department of the Interior — The USGS Southwest Repeat Photography Collection (‘Collection’), formerly named the Desert Laboratory Repeat Photography Collection, is now housed by the Southwest...

  9. A Second Look: Photography as an Experiential and Therapeutic Tool.

    Science.gov (United States)

    Fisk, David L.

    This paper reflects on the motivations for doing photography and examines the therapeutic use of photography with various populations. The paper provides an account of how one person was trained as a teacher in the early 1970s but could not find work. He moved into and then out of social work with the elderly in Chicago. Having learned photography…

  10. Photographing Turkey Run: A Guide to Nature Photography

    OpenAIRE

    Shepardson, Daniel P.

    2016-01-01

    Photographing Turkey Run: A Guide to Nature Photography was written to be used in conjunction with Daniel P. Shepardson’s A Place Called Turkey Run: A Celebration of Indiana’s Second State Park in Photographs and Words. This guide contains tips and techniques designed to provide a basic understanding of how to photograph nature and improve one’s photography skills.

  11. Aso Ebi: Fashioning self through photography and 'fashion ...

    African Journals Online (AJOL)

    In Nigeria, fashion and photography have become powerful forces in the construction of self. In this essay, I see photographers as central players in this development, and I examine the intersections of aso ebi, photography and popular media consumption - in the form of popular magazines - in Lagos. The essay argues that ...

  12. Using Digital Photography to Supplement Learning of Biotechnology

    Science.gov (United States)

    Norflus, Fran

    2012-01-01

    The author used digital photography to supplement learning of biotechnology by students with a variety of learning styles and educational backgrounds. Because one approach would not be sufficient to reach all the students, digital photography was used to explain the techniques and results to the class instead of having to teach each student…

  13. Using historical photography to monitor and assess threats over time

    Science.gov (United States)

    Don. Evans

    2010-01-01

    Analysis of aerial photography is perhaps the best way to assess changes in landcover conditions. In the United States, most national forests have repeat photography on approximately a 10-year cycle. Analysis of this rich photo record can reveal changes in insect damage, fuels buildup, unmanaged off-highway vehicle use, loss of open space, and other land-cover...

  14. The Roles of Photography for Developing Literacy across the Disciplines

    Science.gov (United States)

    Cappello, Marva; Lafferty, Karen E.

    2015-01-01

    Teachers can capitalize on the overwhelmingly visual nature of contemporary society for learning and teaching through integrating photography in their classroom instruction. In offering an alternative pathway for acquiring and expressing knowledge, photography has the potential to strengthen instruction across disciplines by drawing on multiple…

  15. 179 The Impact of Photography in a Developing Economy

    African Journals Online (AJOL)

    Nekky Umera

    Abstract. Photography as an image–making process is not quite appreciated by budding artists and professionals as an art form. This study is thus aimed at advancing photography as a versatile creative medium of expression and a veritable tool for research and skill acquisition for employment generation irrespective of ...

  16. The Impact of Photography in a Developing Economy | Irivwieri ...

    African Journals Online (AJOL)

    A number of literatures were reviewed to elicit information about the subject content of photography which discussed the characteristics, types, phases in its historical development and its role in a developing economy. It is found out that photography is a potentially great creative art. In consequence, both professionals and ...

  17. Total body photography for skin cancer screening.

    Science.gov (United States)

    Dengel, Lynn T; Petroni, Gina R; Judge, Joshua; Chen, David; Acton, Scott T; Schroen, Anneke T; Slingluff, Craig L

    2015-11-01

    Total body photography may aid in melanoma screening but is not widely applied due to time and cost. We hypothesized that a near-simultaneous automated skin photo-acquisition system would be acceptable to patients and could rapidly obtain total body images that enable visualization of pigmented skin lesions. From February to May 2009, a study of 20 volunteers was performed at the University of Virginia to test a prototype 16-camera imaging booth built by the research team and to guide development of special purpose software. For each participant, images were obtained before and after marking 10 lesions (five "easy" and five "difficult"), and images were evaluated to estimate visualization rates. Imaging logistical challenges were scored by the operator, and participant opinion was assessed by questionnaire. Average time for image capture was three minutes (range 2-5). All 55 "easy" lesions were visualized (sensitivity 100%, 90% CI 95-100%), and 54/55 "difficult" lesions were visualized (sensitivity 98%, 90% CI 92-100%). Operators and patients graded the imaging process favorably, with challenges identified regarding lighting and positioning. Rapid-acquisition automated skin photography is feasible with a low-cost system, with excellent lesion visualization and participant acceptance. These data provide a basis for employing this method in clinical melanoma screening. © 2014 The International Society of Dermatology.

  18. Shouldering the past: Photography, archaeology, and collective effort at the tomb of Tutankhamun.

    Science.gov (United States)

    Riggs, Christina

    2017-09-01

    Photographing archaeological labor was routine on Egyptian and other Middle Eastern sites during the colonial period and interwar years. Yet why and how such photographs were taken is rarely discussed in literature concerned with the history of archaeology, which tends to take photography as given if it considers it at all. This paper uses photographs from the first two seasons of work at the tomb of Tutankhamun (1922-4) to show that photography contributed to discursive strategies that positioned archaeology as a scientific practice - both in the public presentation of well-known sites and in the self-presentation of archaeologists to themselves and each other. Since the subjects of such photographs are often indigenous laborers working together or with foreign excavators, I argue that the representation of fieldwork through photography allows us to theorize colonial archaeology as a collective activity, albeit one inherently based on asymmetrical power relationships. Through photographs, we can access the affective and embodied experiences that collective effort in a colonial context involved, bringing into question standard narratives of the history and epistemology of archaeology.

  19. A shadow detector for photosynthesis efficiency.

    Science.gov (United States)

    Liao, Kang-Ling; Jones, Roger D; McCarter, Patrick; Tunc-Ozdemir, Meral; Draper, James A; Elston, Timothy C; Kramer, David; Jones, Alan M

    2017-02-07

    Plants tolerate large variations in the intensity of the light environment by controlling the efficiency of solar to chemical energy conversion. To do this, plants have a mechanism to detect the intensity, duration, and change in light as they experience moving shadows, flickering light, and cloud cover. Sugars are the primary products of CO2 fixation, a metabolic pathway that is rate limited by this solar energy conversion. We propose that sugar is a signal encoding information about the intensity, duration and change in the light environment. We previously showed that the Arabidopsis heterotrimeric G protein complex including its receptor-like Regulator of G signaling protein, AtRGS1, detects both the concentration and the exposure time of sugars (Fu et al., 2014. Cell 156: 1084-1095). This unique property, designated dose-duration reciprocity, is a behavior that emerges from the system architecture / system motif. Here, we show that another property of the signaling system is to detect large changes in light while at the same time, filtering types of fluctuation in light that do not affect photosynthesis efficiency. When AtRGS1 is genetically ablated, photosynthesis efficiency is reduced in a changing- but not a constant-light environment. Mathematical modeling revealed that information about changes in the light environment is encoded in the amount of free AtRGS1 that becomes compartmentalized following stimulation. We propose that this property determines when to adjust photosynthetic efficiency in an environment where light intensity changes abruptly caused by moving shadows on top of a background of light changing gradually from sun rise to sun set and fluctuating light such as that caused by fluttering leaves. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Automatic and Accurate Shadow Detection Using Near-Infrared Information.

    Science.gov (United States)

    Rüfenacht, Dominic; Fredembach, Clément; Süsstrunk, Sabine

    2014-08-01

    We present a method to automatically detect shadows in a fast and accurate manner by taking advantage of the inherent sensitivity of digital camera sensors to the near-infrared (NIR) part of the spectrum. Dark objects, which confound many shadow detection algorithms, often have much higher reflectance in the NIR. We can thus build an accurate shadow candidate map based on image pixels that are dark both in the visible and NIR representations. We further refine the shadow map by incorporating ratios of the visible to the NIR image, based on the observation that commonly encountered light sources have very distinct spectra in the NIR band. The results are validated on a new database, which contains visible/NIR images for a large variety of real-world shadow creating illuminant conditions, as well as manually labeled shadow ground truth. Both quantitative and qualitative evaluations show that our method outperforms current state-of-the-art shadow detection algorithms in terms of accuracy and computational efficiency.

  1. Making Graphical Information Visible in Real Shadows on Interactive Tabletops.

    Science.gov (United States)

    Isogawa, Mariko; Iwai, Daisuke; Sato, Kosuke

    2014-09-01

    We introduce a shadow-based interface for interactive tabletops. The proposed interface allows a user to browse graphical information by casting the shadow of his/her body, such as a hand, on a tabletop surface. Central to our technique is a new optical design that utilizes polarization in addition to the additive nature of light so that the desired graphical information is displayed only in a shadow area on a tabletop surface. In other words, our technique conceals the graphical information on surfaces other than the shadow area, such as the surface of the occluder and non-shadow areas on the tabletop surface. We combine the proposed shadow-based interface with a multi-touch detection technique to realize a novel interaction technique for interactive tabletops. We implemented a prototype system and conducted proof-of-concept experiments along with a quantitative evaluation to assess the feasibility of the proposed optical design. Finally, we showed implemented application systems of the proposed shadow-based interface.

  2. Detecting the structural form of cast shadows patterns.

    Science.gov (United States)

    Khuu, Sieu K; Khambiye, Shazaan; Phu, Jack

    2012-10-17

    Cast shadows are ubiquitous in the visual scene and they inform greatly about the scene's three-dimensional spatial layout. In the present study we investigated the ability of the visual system to detect the structural form of cast shadows using Glass patterns consisting of local dot-pairs or dipoles oriented appropriately to convey global structure. "Cast shadow" Glass patterns were constructed by superimposing two opposite polarity (light-increment - the object - and light-decrement - the shadow) concentric Glass patterns and then spatially displacing the decrement pattern along a particular orientation conforming to the pattern's lighting direction. We determined the shadow detection threshold, which specifies the amount of structural difference between the object (increment Glass-pattern) and its respective shadow (decrement Glass-pattern), required for observers to detect the cast shadow. This was achieved by varying the ratio between local opposite-polarity dipole pairs that were appropriately aligned along the lighting direction (congruent dipole pairs), and dipole pairs that were randomly oriented (incongruent dipole pairs), and were therefore inconsistent with the pattern's lighting direction. We reported that thresholds were comparatively lower (i.e., the visual system is able to tolerate greater local pattern inconsistencies) for light-from-above patterns than for light-from-below patterns (Experiment 1), and detection is optimal for highly coherent patterns (Experiment 2) small spatial separations between opposite polarity (Experiment 3). Our findings demonstrated that the visual system is more sensitive to light-from-above configurations when detecting the form of cast shadows, and this detection process largely ignores local inconsistencies between the object and its respective shadow.

  3. Waiting for Shadows from the Distant Solar System

    Science.gov (United States)

    Kohler, Susanna

    2016-03-01

    How can we hope to measure the hundreds of thousands of objects in our distant solar system? A team of astronomers is harnessing citizen science to begin to tackle this problem!A light curve from an occultation collected by a RECON site in Quincy, California. As the objects shadow passes, the background stars light dims. [RECON/Charley Arrowsmith (Feather River College)]Occultation InformationEstimates currently place the number of Kuiper belt objects larger than 100 km across at over 100,000. Knowing the sizes and characteristics of these objects is important for understanding the composition of the outer solar system and constraining models of the solar systems formation and evolution.Unfortunately, measuring small, dim bodies at large distances is incredibly difficult! One of the best ways to obtain the sizes of these objects is to watch as they occult a distant star. Timing the object as it passes across the face of the star can give us a good measure of its size and shape, when observed from multiple stations in the path of the shadow.An Extended NetworkOccultations by nearby objects (like main-belt asteroids) can be predicted fairly accurately, but those by trans-Neptunian objects are much more poorly constrained. Only ~900 trans-Neptunian objects have approximately known paths, and occultation-shadow predictions for these objects are often only accurate to ~1000km on the Earths surface. So how can we ensure that theres a telescope in the right location, ready to observe when an occultation occurs?Map of the 56 RECON sites distributed over 2000 km in the western United States. [Buie et al. 2016]The simplest answer is to set up a huge network of observing stations, and wait for the shadows to come to the network. With this approach, even if the predicted path isnt precisely known, some of the stations will still observe the occultation.Due to the number of stations needed, this project lends itself perfectly to citizen science. In a recently published paper by

  4. Black Hole Shadows of Charged Spinning Black Holes

    OpenAIRE

    Takahashi, Rohta

    2005-01-01

    We propose a method for measuring the black hole charge by imaging a black hole shadow in a galactic center by future interferometers. Even when the black hole is uncharged, it is possible to confirm the charge neutrality by this method. We first derive the analytic formulae of the black hole shadow in an optically thin medium around a charged spinning black hole, and then investigate how contours of the black hole shadow depend on the spin and the charge of the black hole for several inclina...

  5. A locally adaptive algorithm for shadow correction in color images

    Science.gov (United States)

    Karnaukhov, Victor; Kober, Vitaly

    2017-09-01

    The paper deals with correction of color images distorted by spatially nonuniform illumination. A serious distortion occurs in real conditions when a part of the scene containing 3D objects close to a directed light source is illuminated much brighter than the rest of the scene. A locally-adaptive algorithm for correction of shadow regions in color images is proposed. The algorithm consists of segmentation of shadow areas with rank-order statistics followed by correction of nonuniform illumination with human visual perception approach. The performance of the proposed algorithm is compared to that of common algorithms for correction of color images containing shadow regions.

  6. More Efficient Virtual Shadow Maps for Many Lights.

    Science.gov (United States)

    Olsson, Ola; Billeter, Markus; Sintorn, Erik; Kampe, Viktor; Assarsson, Ulf

    2015-06-01

    Recently, several algorithms have been introduced that enable real-time performance for many lights in applications such as games. In this paper, we explore the use of hardware-supported virtual cube-map shadows to efficiently implement high-quality shadows from hundreds of light sources in real time and within a bounded memory footprint. In addition, we explore the utility of ray tracing for shadows from many lights and present a hybrid algorithm combining ray tracing with cube maps to exploit their respective strengths. Our solution supports real-time performance with hundreds of lights in fully dynamic high-detail scenes.

  7. Transmit antenna selection based on shadowing side information

    KAUST Repository

    Yilmaz, Ferkan

    2011-05-01

    In this paper, we propose a new transmit antenna selection scheme based on shadowing side information. In the proposed scheme, single transmit antenna which has the highest shadowing coefficient is selected. By the proposed technique, usage of the feedback channel and channel estimation complexity at the receiver can be reduced. We consider independent but not identically distributed Generalized-K composite fading model, which is a general composite fading & shadowing channel model for wireless environments. Exact closed-form outage probability, moment generating function and symbol error probability expressions are derived. In addition, theoretical performance results are validated by Monte Carlo simulations. © 2011 IEEE.

  8. Gigapixel photography for skin cancer surveillance: a novel alternative to total-body photography.

    Science.gov (United States)

    Mikailov, Anar; Blechman, Adam

    2013-11-01

    There is substantial evidence supporting the use of cutaneous imaging in combination with standard total-body skin examinations for early detection and treatment of melanoma. In the last 2 decades, total-body photography (TBP) has been widely used in combination with standard total-body skin examinations for active skin cancer surveillance with proven clinical utility; however, the groundbreaking image detail provided by gigapixel photography (GP) could improve dermatologists' ability to monitor suspicious lesions and therefore could serve a critical role in supplementing traditional total-body skin examinations for skin cancer surveillance. Although it has been successfully implemented in other fields, future studies are required to determine the effectiveness of GP in dermatology.

  9. Shadows Constructing a Relationship between Light and Color Pigments by Physical and Mathematical Perspectives

    Science.gov (United States)

    Yurumezoglu, Kemal; Karabey, Burak; Koyunkaya, Melike Yigit

    2017-01-01

    Full shadows, partial shadows and multilayer shadows are explained based on the phenomenon of the linear dispersion of light. This paper focuses on progressing the understanding of shadows from physical and mathematical perspectives. A significant relationship between light and color pigments is demonstrated with the help of the concept of sets.…

  10. Shutter/aperture settings for aerial photography

    Science.gov (United States)

    Lockwood, H. E.; Perry, L.

    1976-01-01

    Determination of aerial camera shutter and aperture settings to produce consistently high-quality aerial photographs is a task complicated by numerous variables. Presented in this article are brief discussions of each variable and specific data which may be used for the systematic control of each. The variables discussed include sunlight, aircraft altitude, subject and season, film speed, and optical system. Data which may be used as a base reference are included, and encompass two sets of sensitometric specifications for two film-chemistry processes along with camera-aircraft parameters, which have been established and used to produce good exposures. Information contained here may be used to design and implement an exposure-determination system for aerial photography.

  11. Berenice Abbott (1898-1991, photographies

    Directory of Open Access Journals (Sweden)

    Juliette Mélia

    2012-05-01

    Full Text Available C’est la première fois que Berenice Abbott est exposée à Paris. Les cent vingt images et trente documents présentés au Jeu de Paume sont regroupés en quatre grandes séries, qui correspondent aux quatre grandes phases de sa carrière photographique. La première partie retrace son œuvre de portraitiste, qui commence à Paris au début des années 1920, où elle photographie des anonymes, mais aussi beaucoup d’artistes et d’écrivains tels que Marcel Duchamp, Jean Cocteau, James Joyce, ou encore Djuna...

  12. The use of photography in clinical psychology

    Directory of Open Access Journals (Sweden)

    Francesca Belgiojoso

    2016-04-01

    Full Text Available The article present and investigate different aspects of the use of photography in clinical psychology in order to provide psychotherapists with information about the tools and their reference theory for a better orientation among the different techniques and assess their integration into their clinical work.The article describes the main techniques that include the use of photographs in psycphoto genogram and photolange, with a specific focus on Judy Weiser’s PhotoTherapy Techniques. We then present data from an exploratory qualitative research on the use of Photo Therapy Techniques by the authors (psychotherapists of different orientations with their patients. The focus is on understanding when, with whom and why a therapist proposes a specific technique, how he uses the photographs, wich difficulty he can meet and how to manage it.hotherapy (such as collage, the

  13. Measuring food intake with digital photography.

    Science.gov (United States)

    Martin, C K; Nicklas, T; Gunturk, B; Correa, J B; Allen, H R; Champagne, C

    2014-01-01

    The digital photography of foods method accurately estimates the food intake of adults and children in cafeterias. When using this method, images of food selection and leftovers are quickly captured in the cafeteria. These images are later compared with images of 'standard' portions of food using computer software. The amount of food selected and discarded is estimated based upon this comparison, and the application automatically calculates energy and nutrient intake. In the present review, we describe this method, as well as a related method called the Remote Food Photography Method (RFPM), which relies on smartphones to estimate food intake in near real-time in free-living conditions. When using the RFPM, participants capture images of food selection and leftovers using a smartphone and these images are wirelessly transmitted in near real-time to a server for analysis. Because data are transferred and analysed in near real-time, the RFPM provides a platform for participants to quickly receive feedback about their food intake behaviour and to receive dietary recommendations for achieving weight loss and health promotion goals. The reliability and validity of measuring food intake with the RFPM in adults and children is also reviewed. In sum, the body of research reviewed demonstrates that digital imaging accurately estimates food intake in many environments and it has many advantages over other methods, including reduced participant burden, elimination of the need for participants to estimate portion size, and the incorporation of computer automation to improve the accuracy, efficiency and cost-effectiveness of the method. © 2013 The British Dietetic Association Ltd.

  14. Shadow banking in China: expanding scale, evolving structure

    OpenAIRE

    Li, Cindy

    2013-01-01

    This Asia Focus provides an overview of shadow banking activities in China, their close ties with banks, reasons behind their rapid rise, the range of participants and products, and regulatory issues.

  15. Overestimation of Mach number due to probe shadow

    Science.gov (United States)

    Gosselin, J. J.; Thakur, S. C.; Sears, S. H.; McKee, J. S.; Scime, E. E.; Tynan, G. R.

    2016-07-01

    Comparisons of the plasma ion flow speed measurements from Mach probes and laser induced fluorescence were performed in the Controlled Shear Decorrelation Experiment. We show the presence of the probe causes a low density geometric shadow downstream of the probe that affects the current density collected by the probe in collisional plasmas if the ion-neutral mean free path is shorter than the probe shadow length, Lg = w2 Vdrift/D⊥, resulting in erroneous Mach numbers. We then present a simple correction term that provides the corrected Mach number from probe data when the sound speed, ion-neutral mean free path, and perpendicular diffusion coefficient of the plasma are known. The probe shadow effect must be taken into account whenever the ion-neutral mean free path is on the order of the probe shadow length in linear devices and the open-field line region of fusion devices.

  16. Testing General Relativity with the Shadow Size of Sgr A(*).

    Science.gov (United States)

    Johannsen, Tim; Broderick, Avery E; Plewa, Philipp M; Chatzopoulos, Sotiris; Doeleman, Sheperd S; Eisenhauer, Frank; Fish, Vincent L; Genzel, Reinhard; Gerhard, Ortwin; Johnson, Michael D

    2016-01-22

    In general relativity, the angular radius of the shadow of a black hole is primarily determined by its mass-to-distance ratio and depends only weakly on its spin and inclination. If general relativity is violated, however, the shadow size may also depend strongly on parametric deviations from the Kerr metric. Based on a reconstructed image of Sagittarius A^{*} (Sgr A^{*}) from a simulated one-day observing run of a seven-station Event Horizon Telescope (EHT) array, we employ a Markov chain Monte Carlo algorithm to demonstrate that such an observation can measure the angular radius of the shadow of Sgr A^{*} with an uncertainty of ∼1.5  μas (6%). We show that existing mass and distance measurements can be improved significantly when combined with upcoming EHT measurements of the shadow size and that tight constraints on potential deviations from the Kerr metric can be obtained.

  17. Mount St. Helens Quick Response Damage Assessment Using High-Altitude Infrared Photography

    Science.gov (United States)

    Hinkle, Richard E.; Prill, James C.; Pruitt, John R.

    1981-11-01

    After the destructive volcanic eruption of Mount St. Helens on May 18, 1980, there was a need for a quick response damage assessment. Timeliness of the information was emphasized because of the need to immediately devise land man-agement plans for timber sale operations, rehabilitation efforts, fire protection activities, and areas to be preserved. High-altitude color-infrared photography was collected during May and June by the National Aeronautics and Space Administra-tion (NASA) Ames Research Center (ARC). Interpretation of the photography plus a helicopter trip into the area provided the basis for the construction of 58 map-registered overlays within a 3-week period. These overlays depicted in detail the damage to timber resources, the transportation network, and the watershed. Using the 14 timber loss overlays, U.S. Department of Agriculture (USDA) Forest Service personnel were able to digitize cells depicting ownership, degree of damage, and the preeruption cover classes. These digitized data provided such informa-tion as the total area affected within and outside the national forest, total timber acreage destroyed and damaged, the sizes of timber destroyed, and the acreage of barren land both before and after the eruption. The hydrology and transportation overlays provided information for an alert system to locate areas needing in-depth studies. These problem areas were then studied in detail on low-altitude color photography so that potential erosion sites could receive preventive treatments and essential access roads needed for fire control and timber salvage could be repaired.

  18. Improving topographic/geodesic surveys with use of aerial photography and computers

    Energy Technology Data Exchange (ETDEWEB)

    Subbotin, I.Ye.; Godovannyy, G.N.; Romanchuk, A.G.

    1979-01-01

    At the UkrgiproNIIneft Institute tests have been completed on determining the optimal scale of aerial photography and deriving the required accuracy for a topographic M 1:1000 plan with relief section in 1 m. To decrease the effect of error on data, i.e. coordinates of reference points, on accuracy of phototriangulation, bridging operations are carried out by polygonometry and sectioning using an EOK 2000. One of the most interesting results of the studies is that for planning pipelines and construction elements of an oil production site, the aerial photo scale selected may be smaller (1:10,000) that it is accepted for topographic cartography (1:5000-1:6000). Corrected photos along pipeline pathways and topographic plans of M 1:1000 with various obstacles and linear structures may be derived with an adequate accuracy using M 1:10,000 aerial photography. Use of programs with analytic triangulation and cutting back volume of some aerial photography operations will result in reducing the cost of survey operations and time requirements.

  19. Detection of Clinically Significant Retinopathy of Prematurity Using Wide-angle Digital Retinal Photography

    Science.gov (United States)

    Chiang, Michael F.; Melia, Michele; Buffenn, Angela N.; Lambert, Scott R.; Recchia, Franco M.; Simpson, Jennifer L.; Yang, Michael B.

    2013-01-01

    Objective To evaluate the accuracy of detecting clinically significant retinopathy of prematurity (ROP) using wide-angle digital retinal photography. Methods Literature searches of PubMed and the Cochrane Library databases were conducted last on December 7, 2010, and yielded 414 unique citations. The authors assessed these 414 citations and marked 82 that potentially met the inclusion criteria. These 82 studies were reviewed in full text; 28 studies met inclusion criteria. The authors extracted from these studies information about study design, interventions, outcomes, and study quality. After data abstraction, 18 were excluded for study deficiencies or because they were superseded by a more recent publication. The methodologist reviewed the remaining 10 studies and assigned ratings of evidence quality; 7 studies were rated level I evidence and 3 studies were rated level III evidence. Results There is level I evidence from ≥5 studies demonstrating that digital retinal photography has high accuracy for detection of clinically significant ROP. Level III studies have reported high accuracy, without any detectable complications, from real-world operational programs intended to detect clinically significant ROP through remote site interpretation of wide-angle retinal photographs. Conclusions Wide-angle digital retinal photography has the potential to complement standard ROP care. It may provide advantages through objective documentation of clinical examination findings, improved recognition of disease progression by comparing previous photographs, and the creation of image libraries for education and research. Financial Disclosure(s) Proprietary or commercial disclosure may be found after the references. PMID:22541632

  20. A historical note on illusory contours in shadow writing.

    Science.gov (United States)

    Vezzani, Stefano; Marino, Barbara F M

    2009-01-01

    It is widely accepted that illusory contours have been first displayed and discussed by Schumann (1900, Zeitschrift für Psychologie und Physiologie der Sinnesorgane 23 1-32). Here we show that, before him, Jastrow (1899, Popular Science Monthly 54 299-312) produced illusory contours consisting of a shadow word. A brief history of shadow writing in psychological literature from Jastrow to Brunswik is presented, in which the contributions of Pillsbury, Warren, Koffka, and Benussi are examined.

  1. Nuclear shadowing and the optics of hadronic fluctuations

    Energy Technology Data Exchange (ETDEWEB)

    Mankiewicz, L. E-mail: lech_mankiewicz@camk.edu.pl; Piller, G.; Vaenttinen, M.; Weise, W

    2001-06-04

    A coordinate-space description of shadowing in deep-inelastic lepton-nucleus scattering is presented. The picture in the laboratory frame is that of quark-gluon fluctuations of the high-energy virtual photon, propagating coherently over large light-cone distances in the nuclear medium. We discuss the detailed dependence of the coherence effects on the invariant mass of the fluctuation. We comment on the issue of possible saturation in the shadowing effects at very small Bjorken-x.

  2. Physician shadowing by college students: what do patients think?

    OpenAIRE

    Bing-You, Robert G; Hayes, Victoria M; Skolfield, Jennifer L

    2014-01-01

    Background The objective of this study is to determine patients’ perceptions of physician shadowing by college students. Methods Thirty-two patients who agreed to have a college student shadow their physician participated in semi-structured interviews during July and August 2013 at two outpatient family medicine centers. Qualitative techniques were utilized to analyze the transcripts of the patient interviews and identify common themes. Results The majority of patients (78.1%) felt the colleg...

  3. Spacecraft's Attitude Prediction: Solar Radiation Torque and the Earth's Shadow

    Science.gov (United States)

    Zanardi, M. C.; Vilhena de Moraes, R.; Cabette, R. S.; Garcia, R. V.

    A semi-analytical approach is proposed to study the rotational motion of a spacecraft under the influence of the solar radiation torque and taking into account the influence of the Earth's shadow. The equations of motion are given in an Hamiltonian formalism and Andoyer variables are used to describe the spacecraft rotational motion. The model for the shadow function was developed by Kabelac which considers geometric and physical factors and three specific regions: shadow, penumbra and total illuminated. Special attention is focused on the influence of the orbital elements and the positioning of the Sun in the duration of the Earth's shadow and penumbra. By mapping and computing the shadow function it is possible to get the periods in which the spacecraft is illuminated and when it is in the umbra (in this case the solar radiation torque is zero). The semi-analytical process is applied to get the solution for the equations of motion, using the mapping of the shadow function. When the satellite is illuminated or it is in the penumbra, a known analytical solution is used to predict the spacecraft's attitude. Numerical simulations are presented considering different sets of orbital characteristics for the satellite and positioning of the Sun in the Ecliptic. By numerical results it is possible to observe important influence of the orbital elements on the time for crossing penumbra and shadow regions. Numerical simulations show also that the transition from the shadow region to the illumined region was attenuated when of the penumbra region is included in the dynamical problem.

  4. Introducing Adaptive Filters Based on Shadow Concept for Speech Processing

    OpenAIRE

    Koteswara Rao, M; Prabha, I.Santhi

    2014-01-01

    This paper presents the new approach to introducing adaptive Filter with LMS Algorithm based on Shadow concept. Which is useful for the cancellation of the noise component overlap with Speech signal in the same frequency range, but fixed LMS algorithm produces minimum convergence rate and fixed steady state error. So we presents design, implementation and performance of adaptive FIR filter, based on Shadow concept, which produces minimum mean square error compare to fixed LMS, and we also o...

  5. Ferromagnetic shadow mask for spray coating of polymer patterns

    DEFF Research Database (Denmark)

    Keller, Stephan Sylvest; Bosco, Filippo; Boisen, Anja

    2013-01-01

    We present the fabrication of a wafer-scale shadow mask with arrays of circular holes with diameters of 150–400 μm. Standard UV photolithography is used to define 700 μm thick SU-8 structures followed by electroplating of nickel and etching of the template. The ferromagnetic properties of the sha...... of the shadow mask allow magnetic clamping to the substrate and spray coating of well defined polymer patterns....

  6. Terrestrial hyperspectral image shadow restoration through fusion with terrestrial lidar

    Science.gov (United States)

    Hartzell, Preston J.; Glennie, Craig L.; Finnegan, David C.; Hauser, Darren L.

    2017-05-01

    Recent advances in remote sensing technology have expanded the acquisition and fusion of active lidar and passive hyperspectral imagery (HSI) from exclusively airborne observations to include terrestrial modalities. In contrast to airborne collection geometry, hyperspectral imagery captured from terrestrial cameras is prone to extensive solar shadowing on vertical surfaces leading to reductions in pixel classification accuracies or outright removal of shadowed areas from subsequent analysis tasks. We demonstrate the use of lidar spatial information for sub-pixel HSI shadow detection and the restoration of shadowed pixel spectra via empirical methods that utilize sunlit and shadowed pixels of similar material composition. We examine the effectiveness of radiometrically calibrated lidar intensity in identifying these similar materials in sun and shade conditions and further evaluate a restoration technique that leverages ratios derived from the overlapping lidar laser and HSI wavelengths. Simulations of multiple lidar wavelengths, i.e., multispectral lidar, indicate the potential for HSI spectral restoration that is independent of the complexity and costs associated with rigorous radiometric transfer models, which have yet to be developed for horizontal-viewing terrestrial HSI sensors. The spectral restoration performance of shadowed HSI pixels is quantified for imagery of a geologic outcrop through improvements in spectral shape, spectral scale, and HSI band correlation.

  7. The multisensory body revealed through its cast shadows

    Directory of Open Access Journals (Sweden)

    Francesco ePavani

    2015-05-01

    Full Text Available One key issue when conceiving the body as a multisensory object is how the cognitive system integrates visible instances of the self and other bodies with one’s own somatosensory processing, to achieve self-recognition and body ownership. Recent research has strongly suggested that shadows cast by our own body have a special status for cognitive processing, directing attention to the body in a fast and highly specific manner. The aim of the present article is to review the most recent scientific contributions addressing how body shadows affect both sensory/perceptual and attentional processes. The review examines three main points: (1 body shadows as a special window to investigate the construction of multisensory body perception; (2 experimental paradigms and related findings; (3 open questions and future trajectories. The reviewed literature suggests that shadows cast by one’s own body promote binding between personal and extrapersonal space and elicit automatic orienting of attention toward the body-part casting the shadow. Future research should address whether the effects exerted by body shadows are similar to those observed when observers are exposed to other visual instances of their body. The results will further clarify the processes underlying the merging of vision and somatosensation when creating body representations.

  8. Shadows of Kerr Black Holes with Scalar Hair.

    Science.gov (United States)

    Cunha, Pedro V P; Herdeiro, Carlos A R; Radu, Eugen; Rúnarsson, Helgi F

    2015-11-20

    Using backwards ray tracing, we study the shadows of Kerr black holes with scalar hair (KBHSH). KBHSH interpolate continuously between Kerr BHs and boson stars (BSs), so we start by investigating the lensing of light due to BSs. Moving from the weak to the strong gravity region, BSs-which by themselves have no shadows-are classified, according to the lensing produced, as (i) noncompact, which yield not multiple images, (ii) compact, which produce an increasing number of Einstein rings and multiple images of the whole celestial sphere, and (iii) ultracompact, which possess light rings, yielding an infinite number of images with (we conjecture) a self-similar structure. The shadows of KBHSH, for Kerr-like horizons and noncompact BS-like hair, are analogous to, but distinguishable from, those of comparable Kerr BHs. But for non-Kerr-like horizons and ultracompact BS-like hair, the shadows of KBHSH are drastically different: novel shapes arise, sizes are considerably smaller, and multiple shadows of a single BH become possible. Thus, KBHSH provide quantitatively and qualitatively new templates for ongoing (and future) very large baseline interferometry observations of BH shadows, such as those of the Event Horizon Telescope.

  9. Light - Shadow Interactions in Italian Medieval Churches

    Science.gov (United States)

    Incerti, Manuela

    In the relationship between architecture and the sky, it is possible to identify three different design issues. The first regards the alignment of buildings with visible points on the horizon that coincide with the rising or setting of a celestial body (sun, planets, stars, or moon) on particular dates during the astronomical year (or liturgical year for sacred buildings). The second is the relationship between planimetric design and the design of the elevations. We are all familiar today with several "light effects", which sometimes have almost hierophanic characteristics that, on certain days of the year, were used to engross, captivate, and amaze the spectator. Contrary to the first two issues, the third comes after the design and building stages and concerns the question of decorative elements. It is reasonable to believe that many years after the works were terminated, certain wall finishings were chosen over others, such as painted frescoes or statues. Whoever did this was fully aware, thanks to direct observation, that such decoration would be struck by a single ray of light on a specific day. This chapter examines light-shadow interactions in some Italian medieval churches.

  10. Smartphone based Tomographic PIV using colored shadows

    Science.gov (United States)

    Aguirre-Pablo, Andres A.; Alarfaj, Meshal K.; Li, Er Qiang; Thoroddsen, Sigurdur T.

    2016-11-01

    We use low-cost smartphones and Tomo-PIV, to reconstruct the 3D-3C velocity field of a vortex ring. The experiment is carried out in an octagonal tank of water with a vortex ring generator consisting of a flexible membrane enclosed by a cylindrical chamber. This chamber is pre-seeded with black polyethylene microparticles. The membrane is driven by an adjustable impulsive air-pressure to produce the vortex ring. Four synchronized smartphone cameras, of 40 Mpx each, are used to capture the location of particles from different viewing angles. We use red, green and blue LED's as backlighting sources, to capture particle locations at different times. The exposure time on the smartphone cameras are set to 2 seconds, while exposing each LED color for about 80 μs with different time steps that can go below 300 μs. The timing of these light pulses is controlled with a digital delay generator. The backlight is blocked by the instantaneous location of the particles in motion, leaving a shadow of the corresponding color for each time step. The image then is preprocessed to separate the 3 different color fields, before using the MART reconstruction and cross-correlation of the time steps to obtain the 3D-3C velocity field. This proof of concept experiment represents a possible low-cost Tomo-PIV setup.

  11. Celestial shadows eclipses, transits, and occultations

    CERN Document Server

    Westfall, John

    2015-01-01

    Much of what is known about the universe comes from the study of celestial shadows—eclipses, transits, and occultations.  The most dramatic are total eclipses of the Sun, which constitute one of the most dramatic and awe-inspiring events of nature.  Though once a source of consternation or dread, solar eclipses now lead thousands of amateur astronomers and eclipse-chasers to travel to remote points on the globe to savor their beauty and the adrenaline-rush of experiencing totality, and were long the only source of information about the hauntingly beautiful chromosphere and corona of the Sun.   Long before Columbus, the curved shadow of the Earth on the Moon during a lunar eclipse revealed that we inhabit a round world. The rare and wonderful transits of Venus, which occur as it passes between the Earth and the Sun, inspired eighteenth century expeditions to measure the distance from the Earth to the Sun, while the recent transits of 2004 and 2012 were the most widely observed ever--and still produced re...

  12. Eclipsing Aestheticism: Western Landscape Photography After Ansel Adams

    National Research Council Canada - National Science Library

    Dennis, Kelly

    2015-01-01

    Although Ansel Adams’s (1902-84) photographic legacy remains indisputable in mass culture and among museums and collectors, the nature of that legacy has been in contention among contemporary artists, scholars, and theorists of photography...

  13. Clinical photography for trichology practice: tips and tricks.

    Science.gov (United States)

    Ashique, Kt; Kaliyadan, Feroze

    2011-01-01

    Clinical photography of hair disorders is an extension of photography in dermatology practice. Some points should be kept in mind while taking images of the hair and hair bearing areas in view of the reflection of light and the subsequent glare that may spoil the result. For documentation of most conditions of the hair, the same general rules of dermatological photography apply. The correct lighting is the most important aspect of clinical photography in trichology practice and can be achieved by reflected light than direct light. Special care should be taken in conditions requiring serial images to document progress/response to treatment and the most important factor in this context is consistency with respect to patient positioning, lighting, camera settings and background. Dermoscopy/trichoscopy can also be incorporated in clinical practice for image documentation.

  14. Aerial Photography and Imagery, Ortho-Corrected - FDOT 2006 Orthophotography

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — This Imagery was provided by Florida Department of Transportation to the Volusia County Property Appraiser. The photography was acquired Dec 2005 through Feb 2006. 1...

  15. Land Cover Trends Geotagged Photography: 1999-2007

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The United States Geological Survey (USGS) Land Cover Trends field photography collection is a national-scale, ground-reference dataset which initially served as a...

  16. NHAP = National High-Altitude Aerial Photography: 1980 - 1989

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The National High Altitude Photography (NHAP) program, which was operated from 1980-1989, was coordinated by the U.S. Geological Survey as an interagency project to...

  17. Photojournalism: Microcomputer Text Editing and Photography--Synthesis and Divergence.

    Science.gov (United States)

    Sheie, Timothy P.

    1983-01-01

    An interdisciplinary project for secondary level mainstreamed hearing impaired students employed photography, word processing, journalism, and graphic arts to promote independent creativity. Academic skills were taught or remediated via this approach, which was motivating to the students. (CL)

  18. [Investigation about particularity of dental clinical digital photography].

    Science.gov (United States)

    Liu, Feng

    2012-04-01

    Dental photography is one of the special field in photography because of the particularity of the technology and approach. Lack of depth of field is one of the most possible problems for new learners. In dental photography, the control of depth of field depends on aperture only, deep depth of field can be achieved by decreasing the aperture. The parameters of exposure include aperture, shutter speed, flash intensity and ISO, which control the exposure together. The area of pictures is controlled by proportion, with manual exposure for getting right exposure. Manual focusing is suggested instead of auto focusing. The appropriate technology, method and right area are the most important factors for dental photography, and later treatment has to be avoided.

  19. Colposcopic photography of genital injury following sexual intercourse in adults

    DEFF Research Database (Denmark)

    Astrup, Birgitte Schmidt; Lauritsen, Jens; Thomsen, Jørgen Lange

    2013-01-01

    The aim of this study was to evaluate interpretations and the reproducibility of interpretations when looking at colposcopic photographs in a forensic setting, as well as discussing some of the dilemmas and pitfalls of forensic colposcopic photography. A total of 316 colposcopic photographs from 51...... and negative predictive values of the photographs were 82 and 81 % respectively. This study demonstrates relatively poor reliability of colposcopic photography. Some would argue that this makes colposcopic photography a low-quality method of evaluation and that forensic science should aim for higher standards...... because of its use in court. Others would argue that as long as the limitations of a scientific method are acknowledged then it is still eligible for use. The moderate agreement and accuracy stresses the need for quality control in the gynecological part of a rape examination. Colposcopic photography also...

  20. Medical photography: current technology, evolving issues and legal perspectives.

    Science.gov (United States)

    Harting, M T; DeWees, J M; Vela, K M; Khirallah, R T

    2015-04-01

    Medical photographic image capture and data management has undergone a rapid and compelling change in complexity over the last 20 years. This is because of multiple factors, including significant advances in ease of photograph capture, alongside an evolution of mechanisms of data portability/dissemination, combined with governmental focus on health information privacy. Literature to guide medical, legal, governmental and business professionals when dealing with issues related to medical photography is virtually nonexistent. Herein, we will address the breadth of uses of medical photography, device properties/specific devices utilised for image capture, methods of data transfer and dissemination and patient perceptions and attitudes regarding photography in a medical setting. In addition, we will address the legal implications, including legal precedent, copyright and privacy law, informed consent, protected health information and the Health Insurance Portability and Accountability Act (HIPAA), as they pertain to medical photography. © 2015 John Wiley & Sons Ltd.

  1. Characterising argon-bomb balloons for high-speed photography

    CSIR Research Space (South Africa)

    Olivier, M

    2013-08-01

    Full Text Available -1 SABO 2013 TME Workshop Alkantpan Characterising Argon-bomb balloons for High-speed Photography M Olivier and FJ Mostert Landward Sciences, Defence Peace Safety and Security, CSIR, Meiring Naude Road, Pretoria, RSA. Abstract A...

  2. Framing the Photographer: Discourse and Performance in Portrait Photography

    OpenAIRE

    Dean, Alison Vivian

    2015-01-01

    Framing the Photographer: Discourse and Performance in Portrait Photography reconsiders photographic criticism, theory, and history in terms of the photographic event. I argue that discursive frames—whether formed through art history, juridical language, technological format, or otherwise—inform and interact with the formal composition of photographs, the channels through which photography circulates, and the attitudes and performances of the photographers themselves. Rather than representing...

  3. Saturn's rings thickness with the shadow hiding

    Science.gov (United States)

    Deau, Estelle; Brahic, André; Porco, Carolyn

    Using the Hapke shadow hiding model on various curves phases of ISS/Cassini, we were able to compute the thickness of Saturn's rings through the photometric filling factor. Our results show that diffuse rings (C ring and Cassini Division) are distributed in a monolayer with a thickness from a few centimeters to 5 meters. This seems to suggest that the layer is smaller than the larger particles. For the A and B rings, we find a thickness ranging from 10 to 20 meters, then leading to multiple layers of particles. Our results for the A ring are systematically lower than the values derived by density waves (Tiscareno et al., 2007) and dynamical simulations of Salo and Kaarjalainen (2003). For the first one, this can be explain by the fact the vertical height of the density waves are the upper limit of the real height. Indeed, the wakes (Julian & Toomre, 1966; Salo 1995) conduce the viscosity in the A ring (Daisaka et al., 2001), and produce random speeds greater in the ring plane than in the vertical direction (Daisaka & Ida, 1999), thereby reducing the thickness given by the vertical random speed used to compute the vertical height. However, for the latter one, simulations lead in all the cases (A and B rings such as C ring and Cassini Division) to vertical height of few meters. This constancy can be explained by the fact that simulations take a size distribution too truncated, and a coefficient of restitution rather simple (indeed, rings reflect different surface conditions related to the optical depth, thus the Bridges' law could not promote only one type of collisions). Finally, our results prefer monolayer (layer smaller than the larger particles which allow multilayer of smaller particules) for the faint rings (C ring and Cassini Division) and multilayer for the A and B rings.

  4. Agricultural cropland mapping using black-and-white aerial photography, Object-Based Image Analysis and Random Forests

    Science.gov (United States)

    Vogels, M. F. A.; de Jong, S. M.; Sterk, G.; Addink, E. A.

    2017-02-01

    Land-use and land-cover (LULC) conversions have an important impact on land degradation, erosion and water availability. Information on historical land cover (change) is crucial for studying and modelling land- and ecosystem degradation. During the past decades major LULC conversions occurred in Africa, Southeast Asia and South America as a consequence of a growing population and economy. Most distinct is the conversion of natural vegetation into cropland. Historical LULC information can be derived from satellite imagery, but these only date back until approximately 1972. Before the emergence of satellite imagery, landscapes were monitored by black-and-white (B&W) aerial photography. This photography is often visually interpreted, which is a very time-consuming approach. This study presents an innovative, semi-automated method to map cropland acreage from B&W photography. Cropland acreage was mapped on two study sites in Ethiopia and in The Netherlands. For this purpose we used Geographic Object-Based Image Analysis (GEOBIA) and a Random Forest classification on a set of variables comprising texture, shape, slope, neighbour and spectral information. Overall mapping accuracies attained are 90% and 96% for the two study areas respectively. This mapping method increases the timeline at which historical cropland expansion can be mapped purely from brightness information in B&W photography up to the 1930s, which is beneficial for regions where historical land-use statistics are mostly absent.

  5. Promoting Positive Affect through Smartphone Photography.

    Science.gov (United States)

    Chen, Yu; Mark, Gloria; Ali, Sanna

    With the increasing quality of smartphone cameras, taking photos has become ubiquitous. This paper investigates how smartphone photography can be leveraged to help individuals increase their positive affect. Applying findings from positive psychology, we designed and conducted a 4-week study with 41 participants. Participants were instructed to take one photo every day in one of the following three conditions: a selfie photo with a smiling expression, a photo of something that would make oneself happy and a photo of something that would make another person happy. After 3 weeks, participants' positive affect in all conditions increased. Those who took photos to make others happy became much less aroused. Qualitative results showed that those in the selfie group observed changes in their smile over time; the group taking photos to improve their own affect became more reflective and those taking photos for others found that connecting with family members and friends helped to relieve stress. The findings can offer insights for designers to create systems that enhance emotional well-being.

  6. Learning deep similarity in fundus photography

    Science.gov (United States)

    Chudzik, Piotr; Al-Diri, Bashir; Caliva, Francesco; Ometto, Giovanni; Hunter, Andrew

    2017-02-01

    Similarity learning is one of the most fundamental tasks in image analysis. The ability to extract similar images in the medical domain as part of content-based image retrieval (CBIR) systems has been researched for many years. The vast majority of methods used in CBIR systems are based on hand-crafted feature descriptors. The approximation of a similarity mapping for medical images is difficult due to the big variety of pixel-level structures of interest. In fundus photography (FP) analysis, a subtle difference in e.g. lesions and vessels shape and size can result in a different diagnosis. In this work, we demonstrated how to learn a similarity function for image patches derived directly from FP image data without the need of manually designed feature descriptors. We used a convolutional neural network (CNN) with a novel architecture adapted for similarity learning to accomplish this task. Furthermore, we explored and studied multiple CNN architectures. We show that our method can approximate the similarity between FP patches more efficiently and accurately than the state-of- the-art feature descriptors, including SIFT and SURF using a publicly available dataset. Finally, we observe that our approach, which is purely data-driven, learns that features such as vessels calibre and orientation are important discriminative factors, which resembles the way how humans reason about similarity. To the best of authors knowledge, this is the first attempt to approximate a visual similarity mapping in FP.

  7. Reconstruction of crimes by infrared photography.

    Science.gov (United States)

    Sterzik, V; Bohnert, M

    2016-09-01

    Whenever blunt or sharp forces are used in a crime, analysis of bloodstain pattern distribution may provide important information for the reconstruction of happenings. Thereby, attention should be paid to both the crime scene and the clothes of everyone involved in the crime. On dark textiles, though, it is difficult or even impossible for the human eye to detect bloodstains because of the low contrast to the background. However, in the near infrared wavelength range, contrast is considerably higher. Many textiles reflect light beyond a wavelength of 830 nm and thus appear light-colored, whereas blood absorbs the light and appears dark. In our studies, a D7000 NIKON reflex camera modified for infrared photography produced high-resolution photographs visualizing even very small spatter stains on dark textiles. The equipment can be used at any crime scene or lab and provides immediately available and interpretable images. Thus, important findings can be obtained at an early stage of police investigations, as two examples (homicide and attempted homicide) illustrate.

  8. Fundus Photography as a Screening Method for Diabetic Retinopathy in Children With Type 1 Diabetes: Outcome of the Initial Photography.

    Science.gov (United States)

    Gräsbeck, Thomas C; Gräsbeck, Sophia V; Miettinen, Päivi J; Summanen, Paula A

    2016-09-01

    To determine the success rate of the initial fundus photography session in producing gradable images for screening diabetic retinopathy in children Photography success was classified as "complete" if both images of both eyes were gradable, "partial" if both images of 1 eye were gradable, "macula-centered image(s) only" if only the macula-centered image of one or both eyes was gradable, and "unsuccessful" if neither macula-centered image was gradable. Complete success was reached in 97 (46%; 95% confidence interval [CI], 39-52) patients, at least partial success in 153 (72%; 95% CI, 65-78) patients, success of macula-centered image(s) only in 47 (22%; 95% CI, 17-28) patients, and in 13 (6%; 95%CI, 3-10) patients fundus photography was unsuccessful. Macula-centered images were more often gradable in both eyes than optic disc-centered images (P photography did not differ between right and left eye. Sex, age at diagnosis of T1D, and the duration of diabetes, age, and glycemic control at the time of initial photography were unassociated with complete success. Partial success tended to decrease with increasing age category (P = .093), and the frequency of gradable macula-centered image(s) only increased with increasing age (P = .043). Less than half of the children achieved complete success, but in only 6% initial fundus photography was unsuccessful, indicating its value in assessing retinopathy in the pediatric setting. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. The interrupted power law and the size of shadow banking.

    Science.gov (United States)

    Fiaschi, Davide; Kondor, Imre; Marsili, Matteo; Volpati, Valerio

    2014-01-01

    Using public data (Forbes Global 2000) we show that the asset sizes for the largest global firms follow a Pareto distribution in an intermediate range, that is "interrupted" by a sharp cut-off in its upper tail, where it is totally dominated by financial firms. This flattening of the distribution contrasts with a large body of empirical literature which finds a Pareto distribution for firm sizes both across countries and over time. Pareto distributions are generally traced back to a mechanism of proportional random growth, based on a regime of constant returns to scale. This makes our findings of an "interrupted" Pareto distribution all the more puzzling, because we provide evidence that financial firms in our sample should operate in such a regime. We claim that the missing mass from the upper tail of the asset size distribution is a consequence of shadow banking activity and that it provides an (upper) estimate of the size of the shadow banking system. This estimate-which we propose as a shadow banking index-compares well with estimates of the Financial Stability Board until 2009, but it shows a sharper rise in shadow banking activity after 2010. Finally, we propose a proportional random growth model that reproduces the observed distribution, thereby providing a quantitative estimate of the intensity of shadow banking activity.

  10. eShadow: A tool for comparing closely related sequences

    Energy Technology Data Exchange (ETDEWEB)

    Ovcharenko, Ivan; Boffelli, Dario; Loots, Gabriela G.

    2004-01-15

    Primate sequence comparisons are difficult to interpret due to the high degree of sequence similarity shared between such closely related species. Recently, a novel method, phylogenetic shadowing, has been pioneered for predicting functional elements in the human genome through the analysis of multiple primate sequence alignments. We have expanded this theoretical approach to create a computational tool, eShadow, for the identification of elements under selective pressure in multiple sequence alignments of closely related genomes, such as in comparisons of human to primate or mouse to rat DNA. This tool integrates two different statistical methods and allows for the dynamic visualization of the resulting conservation profile. eShadow also includes a versatile optimization module capable of training the underlying Hidden Markov Model to differentially predict functional sequences. This module grants the tool high flexibility in the analysis of multiple sequence alignments and in comparing sequences with different divergence rates. Here, we describe the eShadow comparative tool and its potential uses for analyzing both multiple nucleotide and protein alignments to predict putative functional elements. The eShadow tool is publicly available at http://eshadow.dcode.org/

  11. The Interrupted Power Law and the Size of Shadow Banking

    Science.gov (United States)

    Fiaschi, Davide; Kondor, Imre; Marsili, Matteo; Volpati, Valerio

    2014-01-01

    Using public data (Forbes Global 2000) we show that the asset sizes for the largest global firms follow a Pareto distribution in an intermediate range, that is “interrupted” by a sharp cut-off in its upper tail, where it is totally dominated by financial firms. This flattening of the distribution contrasts with a large body of empirical literature which finds a Pareto distribution for firm sizes both across countries and over time. Pareto distributions are generally traced back to a mechanism of proportional random growth, based on a regime of constant returns to scale. This makes our findings of an “interrupted” Pareto distribution all the more puzzling, because we provide evidence that financial firms in our sample should operate in such a regime. We claim that the missing mass from the upper tail of the asset size distribution is a consequence of shadow banking activity and that it provides an (upper) estimate of the size of the shadow banking system. This estimate–which we propose as a shadow banking index–compares well with estimates of the Financial Stability Board until 2009, but it shows a sharper rise in shadow banking activity after 2010. Finally, we propose a proportional random growth model that reproduces the observed distribution, thereby providing a quantitative estimate of the intensity of shadow banking activity. PMID:24728096

  12. Shadows of Kerr black holes with scalar hair

    CERN Document Server

    Cunha, Pedro V P; Radu, Eugen; Runarsson, Helgi F

    2015-01-01

    Using backwards ray tracing, we study the shadows of Kerr black holes with scalar hair (KBHsSH). KBHsSH interpolate continuously between Kerr BHs and boson stars (BSs), so we start by investigating the lensing of light due to BSs. Moving from the weak to the strong gravity region, BSs - which by themselves have no shadows - are classified, according to the lensing produced, as: $(i)$ non-compact, which yield no multiple images; $(ii)$ compact, which produce an increasing number of Einstein rings and multiple images of the whole celestial sphere; $(iii)$ ultra-compact, which possess light rings, yielding an infinite number of images with (we conjecture) a self-similar structure. The shadows of KBHsSH, for Kerr-like horizons and non-compact BS-like hair, are analogous to, but distinguishable from, those of comparable Kerr BHs. But for non-Kerr-like horizons and ultra-compact BS-like hair, the shadows of KBHsSH are drastically different: novel shapes arise, sizes are considerably smaller and multiple shadows of ...

  13. Using Shadow Page Cache to Improve Isolated Drivers Performance

    Directory of Open Access Journals (Sweden)

    Hao Zheng

    2015-01-01

    Full Text Available With the advantage of the reusability property of the virtualization technology, users can reuse various types and versions of existing operating systems and drivers in a virtual machine, so as to customize their application environment. In order to prevent users’ virtualization environments being impacted by driver faults in virtual machine, Chariot examines the correctness of driver’s write operations by the method of combining a driver’s write operation capture and a driver’s private access control table. However, this method needs to keep the write permission of shadow page table as read-only, so as to capture isolated driver’s write operations through page faults, which adversely affect the performance of the driver. Based on delaying setting frequently used shadow pages’ write permissions to read-only, this paper proposes an algorithm using shadow page cache to improve the performance of isolated drivers and carefully study the relationship between the performance of drivers and the size of shadow page cache. Experimental results show that, through the shadow page cache, the performance of isolated drivers can be greatly improved without impacting Chariot’s reliability too much.

  14. Physical models for moving shadow and object detection in video.

    Science.gov (United States)

    Nadimi, Sohail; Bhanu, Bir

    2004-08-01

    Current moving object detection systems typically detect shadows cast by the moving object as part of the moving object. In this paper, the problem of separating moving cast shadows from the moving objects in an outdoor environment is addressed. Unlike previous work, we present an approach that does not rely on any geometrical assumptions such as camera location and ground surface/object geometry. The approach is based on a new spatio-temporal albedo test and dichromatic reflection model and accounts for both the sun and the sky illuminations. Results are presented for several video sequences representing a variety of ground materials when the shadows are cast on different surface types. These results show that our approach is robust to widely different background and foreground materials, and illuminations.

  15. Apodized pixel lenses in compact shadow-casting correlators.

    Science.gov (United States)

    Raj, K; Athale, R A

    1995-04-10

    We present a compact two-dimensional shadow-casting correlator that can perform correlation between inputs of size 256 × 256 and a point-spread function of size 32 × 32. A two-dimensional array of mutually incoherent sources is used to encode the point-spread function, and each source is individually steered to improve the light uniformity and the light-utilization efficiency. The geometric optics constraint requires that the shadow region be very close to the input plane. This constraint is removed by the introduction of apodized pixel lenses in the input spatial light modulator. The pixel lenses move the shadow plane to their Fourier plane, and pixel apodization reduces the interchannel cross talk, thereby improving the signal-to-noise ratio. Simulation and experimental results verifying these concepts are presented.

  16. Multiple shooting shadowing for sensitivity analysis of chaotic dynamical systems

    Science.gov (United States)

    Blonigan, Patrick J.; Wang, Qiqi

    2018-02-01

    Sensitivity analysis methods are important tools for research and design with simulations. Many important simulations exhibit chaotic dynamics, including scale-resolving turbulent fluid flow simulations. Unfortunately, conventional sensitivity analysis methods are unable to compute useful gradient information for long-time-averaged quantities in chaotic dynamical systems. Sensitivity analysis with least squares shadowing (LSS) can compute useful gradient information for a number of chaotic systems, including simulations of chaotic vortex shedding and homogeneous isotropic turbulence. However, this gradient information comes at a very high computational cost. This paper presents multiple shooting shadowing (MSS), a more computationally efficient shadowing approach than the original LSS approach. Through an analysis of the convergence rate of MSS, it is shown that MSS can have lower memory usage and run time than LSS.

  17. The fingerprints of black holes—shadows and their degeneracies

    Science.gov (United States)

    Mars, Marc; Paganini, Claudio F.; Oancea, Marius A.

    2018-01-01

    We show that, away from the axis of symmetry, no continuous degeneration exists between the shadows of observers at any point in the exterior region of any Kerr–Newman black hole spacetime of unit mass. Therefore, except possibly for discrete changes, an observer can, by measuring the black holes shadow, determine the angular momentum and the charge of the black hole under observation as well as the observer’s radial position and angle of elevation above the equatorial plane. Furthermore, his/her relative velocity compared to a standard observer can also be measured. However, the black hole shadow does not allow for a full parameter resolution in the case of a Kerr–Newman–Taub–NUT black hole, as a continuous degeneration relating specific angular momentum, electric charge, Taub–NUT charge and elevation angle exists in this case.

  18. The Dark Shadow of Virtual Reality

    Directory of Open Access Journals (Sweden)

    Claire Su-Yeon Park

    2018-01-01

    Full Text Available Virtual Reality (VR technology are entering nursing education at a rapid speed (Foronda et al., 2017. VR has been reported in the nursing literature to significantly improve students’ performance (Jenson & Forsyth, 2012; Park, 2016; Foronda et al., 2017 even though the body of evidence in terms of the number and research quality of peer reviewed research papers is not yet substantial enough to identify VR technology’s effectiveness. However, VR is not actually reality. VR may not actually reflect reality. Young people (and even adults may not perceive the different between reality and VR. They may not yet be mature enough to distinguish the difference. However, VR technology are going much further than traditional educational methods by allowing humans to experience a much higher level of immersion through a virtual image. Even the gap between advances in VR technology and its application to education science is widening, causing serious concern. The advance in VR technology is value-neutral. As with all things, whether something is good or bad depends on how humans use it. VR can be useful, for example, when it enables scholars to attend an international conference without traveling to the physical convention center. VR provides the ability to speak, listen, and discuss in real time. Those using VR can choose to view a featured or real-time image of the other participants as if they were actually at the conference. Further, remote participants can feel touch through electronic sensors attached to their body. How amazing! The problem with VR lies in the fact that we are not ready to cope with any possible harmful influences caused by advances in VR technology. But what is the “Dark Shadow of VR,” and why does it cause concern, particularly in pedagogy? Luc Besson’s 2017 film Valerian and the City of a Thousand Plants showed an exceptional VR world, “Big Market,” a shopping-focused VR platform. But such a world is no longer strictly

  19. Shadow correction in high dynamic range images for generating orthophotos

    Science.gov (United States)

    Suzuki, Hideo; Chikatsu, Hirofumi

    2011-07-01

    High dynamic range imagery is widely used in remote sensing. With the widespread use of aerial digital cameras such as the DMC, ADS40, RMK-D, and UltraCamD, high dynamic range imaging is generally expected for generating minuteness orthophotos in digital aerial photogrammetry. However, high dynamic range images (12-bit, 4,096 gray levels) are generally compressed into an 8-bit depth digital image (256 gray levels) owing to huge amount of data and interface with peripherals such as monitors and printers. This means that a great deal of image data is eliminated from the original image, and this introduces a new shadow problem. In particular, the influence of shadows in urban areas causes serious problems when generating minuteness orthophotos and performing house detection. Therefore, shadow problems can be solved by addressing the image compression problems. There is a large body of literature on image compression techniques such as logarithmic compression and tone mapping algorithms. However, logarithmic compression tends to cause loss of details in dark and/or light areas. Furthermore, the logarithmic method intends to operate on the full scene. This means that high-resolution luminance information can not be obtained. Even though tone mapping algorithms have the ability to operate over both full scene and local scene, background knowledge is required. To resolve the shadow problem in digital aerial photogrammetry, shadow areas should be recognized and corrected automatically without the loss of luminance information. To this end, a practical shadow correction method using 12-bit real data acquired by DMC is investigated in this paper.

  20. A novel ultraviolet photography technique for assessing photodamage.

    Science.gov (United States)

    Draelos, Zoe Diana; Klein, Gregory; Biancone, Gregory

    2008-09-01

    Photography is critical to accurately capturing clinical results in cosmetic dermatology. However, this shift from film to digital photography has made the capture of true ultraviolet (UV) images more difficult. Film cameras were developed that used special lighting and film to create true UV images, but this technology has not translated into the digital realm. At present, commercial digital photography systems use computer processing to generate UV-like images from visible light photography. This research developed a technique to obtain UV images with a UV pass glass filter placed in front of the camera lens. The UV filter was opaque to visible light (400-750 nm) with a peak transmission at 360 nm. In addition, a glass infrared (IR) block filter was also placed in front of the UV filter during photography. This research resulted in the development of an affordable digital camera system that was able to capture true UV light photographs. This technique can be used by research and clinical dermatologists to obtain photographs demonstrating changes in photodamage as a result of therapeutic intervention.

  1. The art and science of photography in hand surgery.

    Science.gov (United States)

    Wang, Keming; Kowalski, Evan J; Chung, Kevin C

    2014-03-01

    High-quality medical photography plays an important role in teaching and demonstrating the functional capacity of the hands as well as in medicolegal documentation. Obtaining standardized, high-quality photographs is now an essential component of many surgery practices. The importance of standardized photography in facial and cosmetic surgery has been well documented in previous studies, but no studies have thoroughly addressed the details of photography for hand surgery. In this paper, we provide a set of guidelines and basic camera concepts for different scenarios to help hand surgeons obtain appropriate and informative high-quality photographs. A camera used for medical photography should come equipped with a large sensor size and an optical zoom lens with a focal length ranging anywhere from 14 to 75 mm. In a clinic or office setting, we recommend 6 standardized views of the hand and 4 views for the wrist; additional views should be taken for tendon ruptures, nerve injuries, or other deformities of the hand. For intraoperative pictures, the camera operator should understand the procedure and pertinent anatomy in order to properly obtain high-quality photographs. When digital radiographs are not available and radiographic film must be photographed, it is recommended to reduce the exposure and change the color mode to black and white to obtain the best possible pictures. The goal of medical photography is to present the subject in an accurate and precise fashion. Copyright © 2014 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  2. Bereavement Photography for Children: Program Development and Healthcare Professionals’ Response

    Science.gov (United States)

    Michelson, Kelly Nicole; Blehart, Kathleen; Hochberg, Todd; James, Kristin; Frader, Joel

    2013-01-01

    Reports of in-hospital bereavement photography focus largely on stillborns and neonates. Empiric data regarding the implementation of bereavement photography in pediatrics beyond the neonatal period and the impact of such programs on healthcare professionals (HCPs) is lacking. We describe the implementation of a pediatric intensive care unit (PICU) bereavement photography program and use questionnaire data from HCPs to describe HCPs’ reflections on the program and to identify program barriers. From July, 2007 through April, 2010 families of 59 (36%) of the 164 patients who died in the PICU participated in our bereavement photography program. Forty questionnaires from 29 HCPs caring for 39 participating patients/families indicated that families seemed grateful for the service (n=34, 85%) and that the program helped HCPs feel better about their role (n=30, 70%). Many HCPs disagreed that the program consumed too much of his/her time (n=34, 85%) and that the photographer made his/her job difficult (n=37, 92.5%). Qualitative analysis of responses to open ended questions revealed four categories: the program’s general value; positive aspects of the program; negative aspects of the program; and suggestions for improvements. Implementing bereavement photography in the PICU is feasible though some barriers exist. HCPs may benefit from such programs. PMID:24520925

  3. Roughness of sandstone fracture surfaces: Profilometry and shadow length investigations

    OpenAIRE

    Boffa, Jean-Marc; Allain, C.; Chertcoff, R.; Hulin, Jean-Pierre; Plouraboué, Franck; Roux, Stéphane

    1999-01-01

    The geometrical properties of fractured sandstone surfaces were studied by measuring the length distribution of the shadows appearing under grazing illumination. Three distinct domains of variation were found: at short length scales a cut-off of self-affinity is observed due to the inter-granular rupture of sandstones, at long length scales, the number of shadows falls off very rapidly because of the non-zero illumination angle and of the finite roughness amplitude. Finally, in the intermediate do...

  4. Wake models developed during the Wind Shadow Project

    DEFF Research Database (Denmark)

    Larsen, Søren Ejling; Ott, Søren; Pena Diaz, Alfredo

    The Wind Shadow project has developed and validated improved models for determining the wakes losses, and thereby the array efficiency of very large, closely packed wind farms. The rationale behind the project has been that the existing software has been covering these types of wind farms poorly......, both with respect to the densely packed turbines and the large fetches needed to describe the collective shadow effects of one farm to the next. Further the project has developed the necessary software for the use of the models. Guidelines with recommendations for the use of the models are included...... in the model deliverables....

  5. Estimating Outdoor Illumination Conditions Based on Detection of Dynamic Shadows

    DEFF Research Database (Denmark)

    Madsen, Claus B.; Lal, Brajesh Behari

    2013-01-01

    The paper proposes a technique for estimation outdoor illumination conditions in terms of sun and sky radiances directly from pixel values of dynamic shadows detected in video sequences produved by a commercial stereo camera. The technique is applied to the rendering of virtual object into the im......The paper proposes a technique for estimation outdoor illumination conditions in terms of sun and sky radiances directly from pixel values of dynamic shadows detected in video sequences produved by a commercial stereo camera. The technique is applied to the rendering of virtual object...

  6. Verification of Aerosol Optical Depth Retrievals using Cloud Shadows Retrieved from Satellite Imagery

    National Research Council Canada - National Science Library

    Sweat, Perry C

    2008-01-01

    ...), IKONOS, and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER). The lower resolution of MODIS and ASTER does not lend itself to focusing on building shadows, but rather cloud shadows...

  7. [Photography and its doubles: a picture on the wall].

    Science.gov (United States)

    Lissovsky, Mauricio; Martins, Juliana

    2013-11-30

    Hans Belting suggests that 'images are the nomads of media' because they set up and dismantle their camps every time new media appear. Whenever photography portrays another image (painting, TV screen) it plays out a chapter in this history. Photography has been the guardian of the paradoxes in the distance and tensions between image and world in modern times. This is why it now holds a central position in the debate about contemporary visuality. Our fate and the fate of images are somehow interconnected. The last generation of visual artists from the twentieth century sought to express the pain of virtualization; twenty-first century photography is rediscovering the promise of a latent body in each image.

  8. [The Indian in Brazilian photography: incursions into image and medium].

    Science.gov (United States)

    Tacca, Fernando de

    2011-03-01

    The article explores contradictions and convergences between a medium (photography) and the image of the Brazilian Indian from the perspective of the history of Brazilian photography. During the first of three distinct moments, the image of the Indian was of someone exotic, in contradiction with the modern meaning of photography under the Second Empire. During the second moment, in the first fifty years of the twentieth century, the boundaries between ethnography and Brazil as a nation were blurred, as exemplified by the Rondon Commission/Indian Protection Bureau's Research Section (Serviço de Proteção ao Índio) and Brazil's modern photojournalism, as found in the magazine Cruzeiro. During the third moment, the expressions of an ethno-poetry present in the photographs of Cláudia Andujar can be seen to blend medium and image as an ethnographic space in contemporary art.

  9. [Application of digital photography in color matching in dentistry].

    Science.gov (United States)

    Shen, Xiao-ting; Fan, Yi; Liu, Li; Zhang, Yan-zhen

    2011-07-01

    To develop a new color matching method in dentistry by application of digital photography. Digital photographs were obtained of Vitapan 3D-Master shade guide and natural teeth under the same condition, the L*a*b* values of each digital photography were assessed and analyzed by Photoshop CS4. The Vitapan 3D-Master shade guide was divided into 5 groups, the L* values were similar in each group, but decreased from group 1 to 5. The a* values of L1.5 and L2.5 were minimum, R1.5 and R2.5 were maximum and M1-M3 were intermediate. Compared with Vitapan 3D-Master shade guide, the L*a*b* values of natural teeth were higher. Digital photography can basically reflect the color of Vitapan 3D-Master shade guide, and provides a reference for color matching in dentistry.

  10. Smartphone photography utilized to measure wrist range of motion.

    Science.gov (United States)

    Wagner, Eric R; Conti Mica, Megan; Shin, Alexander Y

    2018-02-01

    The purpose was to determine if smartphone photography is a reliable tool in measuring wrist movement. Smartphones were used to take digital photos of both wrists in 32 normal participants (64 wrists) at extremes of wrist motion. The smartphone measurements were compared with clinical goniometry measurements. There was a very high correlation between the clinical goniometry and smartphone measurements, as the concordance coefficients were high for radial deviation, ulnar deviation, wrist extension and wrist flexion. The Pearson coefficients also demonstrated the high precision of the smartphone measurements. The Bland-Altman plots demonstrated 29-31 of 32 smartphone measurements were within the 95% confidence interval of the clinical measurements for all positions of the wrists. There was high reliability between the photography taken by the volunteer and researcher, as well as high inter-observer reliability. Smartphone digital photography is a reliable and accurate tool for measuring wrist range of motion. II.

  11. Use of Participant-Generated Photography in a Research Contribution Course

    National Research Council Canada - National Science Library

    Thompson, MaryEllen

    2013-01-01

    .... A comparison of using time-use diaries vs. participant-generated photography is presented to explicate the research process and demonstrate the advantages of using photography, including ease of data collection and data sharing...

  12. USGS Southwest Repeat Photography Collection: Kanab Creek, southern Utah and northern Arizona, 1872-2010

    Data.gov (United States)

    Department of the Interior — The USGS Southwest Repeat Photography Collection (‘Collection’), formerly named the Desert Laboratory Repeat Photography Collection, is now housed by the...

  13. Using gradient-based ray and candidate shadow maps for environmental illumination distribution estimation

    Science.gov (United States)

    Eem, Changkyoung; Kim, Iksu; Hong, Hyunki

    2015-07-01

    A method to estimate the environmental illumination distribution of a scene with gradient-based ray and candidate shadow maps is presented. In the shadow segmentation stage, we apply a Canny edge detector to the shadowed image by using a three-dimensional (3-D) augmented reality (AR) marker of a known size and shape. Then the hierarchical tree of the connected edge components representing the topological relation is constructed, and the connected components are merged, taking their hierarchical structures into consideration. A gradient-based ray that is perpendicular to the gradient of the edge pixel in the shadow image can be used to extract the shadow regions. In the light source detection stage, shadow regions with both a 3-D AR marker and the light sources are partitioned into candidate shadow maps. A simple logic operation between each candidate shadow map and the segmented shadow is used to efficiently compute the area ratio between them. The proposed method successively extracts the main light sources according to their relative contributions on the segmented shadows. The proposed method can reduce unwanted effects due to the sampling positions in the shadow region and the threshold values in the shadow edge detection.

  14. Shadowing: Who Benefits and How? Uncovering a Booming EFL Teaching Technique for Listening Comprehension

    Science.gov (United States)

    Hamada, Yo

    2016-01-01

    This study examines common claims associated with shadowing. Studies in Japan conclude that shadowing is effective for improving learners' listening skills. Two common claims are that shadowing is effective for lower-proficiency learners and that it enhances learners' phoneme perception, thus improving listening comprehension skills. The former…

  15. Review of the SAFARI 2000 RC-10 Aerial Photography

    Science.gov (United States)

    Myers, Jeff; Shelton, Gary; Annegarn, Harrold; Peterson, David L. (Technical Monitor)

    2001-01-01

    This presentation will review the aerial photography collected by the NASA ER-2 aircraft during the SAFARI (Southern African Regional Science Initiative) year 2000 campaign. It will include specifications on the camera and film, and will show examples of the imagery. It will also detail the extent of coverage, and the procedures to obtain film products from the South African government. Also included will be some sample applications of aerial photography for various environmental applications, and its use in augmenting other SAFARI data sets.

  16. New British Fashion Photography: Going Against the Conventionally Beautiful

    OpenAIRE

    Morère, Julie

    2015-01-01

    Dans le cadre théorique selon lequel la photographie de mode britannique est souvent analysée, elle est réduite à sa dimension mercantile (Hall-Duncan), et considérée sous un angle social plutôt qu’artistique (Val Williams). En considérant comment la photographie de mode constitue une archive visuelle du style britannique dans un continuum culturel tissé à travers l’art, la musique, les films ou le design, cet article observera comment les photographes de mode contemporains, les éditeurs, sty...

  17. Reflections about cinema and social photography in City of Gold

    Directory of Open Access Journals (Sweden)

    Nekane Parejo Jiménez

    2009-10-01

    Full Text Available Fernando Meirelles’ film City of God is based on real events, and on a real community which shares the codes of aggressiveness, violence, death, easy money, revenge and leadership. From a functionalist point of view there is a consistency between film and community. But this article will focus on one of the film's characters, Buscapé, for whom photography is a means to break away. Phillipe Dubois’ theories of photography in film serve as a basis to for analysing how Buscapé achieves his escape.

  18. Shadow-Based Vehicle Detection in Urban Traffic.

    Science.gov (United States)

    Ibarra-Arenado, Manuel; Tjahjadi, Tardi; Pérez-Oria, Juan; Robla-Gómez, Sandra; Jiménez-Avello, Agustín

    2017-04-27

    Vehicle detection is a fundamental task in Forward Collision Avoiding Systems (FACS). Generally, vision-based vehicle detection methods consist of two stages: hypotheses generation and hypotheses verification. In this paper, we focus on the former, presenting a feature-based method for on-road vehicle detection in urban traffic. Hypotheses for vehicle candidates are generated according to the shadow under the vehicles by comparing pixel properties across the vertical intensity gradients caused by shadows on the road, and followed by intensity thresholding and morphological discrimination. Unlike methods that identify the shadow under a vehicle as a road region with intensity smaller than a coarse lower bound of the intensity for road, the thresholding strategy we propose determines a coarse upper bound of the intensity for shadow which reduces false positives rates. The experimental results are promising in terms of detection performance and robustness in day time under different weather conditions and cluttered scenarios to enable validation for the first stage of a complete FACS.

  19. Infrasound propagation in tropospheric ducts and acoustic shadow zones.

    Science.gov (United States)

    de Groot-Hedlin, Catherine D

    2017-10-01

    Numerical computations of the Navier-Stokes equations governing acoustic propagation are performed to investigate infrasound propagation in the troposphere and into acoustic shadow zones. An existing nonlinear finite-difference, time-domain (FDTD) solver that constrains input sound speed models to be axisymmetric is expanded to allow for advection and rigid, stair-step topography. The FDTD solver permits realistic computations along a given azimuth. It is applied to several environmental models to examine the effects of nonlinearity, topography, advection, and two-dimensional (2D) variations in wind and sound speeds on the penetration of infrasound into shadow zones. Synthesized waveforms are compared to a recording of a rocket motor fuel elimination event at the Utah Test and Training Range. Results show good agreement in the amplitude, duration, and spectra of synthesized and recorded waveforms for propagation through 2D atmospheric models whether or not topography, advection, or nonlinearity is explicitly included. However, infrasound propagation through a one-dimensional, range-averaged, atmospheric model yields waveforms with lower amplitudes and frequencies, suggesting that small-scale atmospheric variability causes significant scatter within the troposphere, leading to enhanced infrasound penetration into shadow zones. Thus, unresolved fine-scale atmospheric dynamics are not required to explain infrasound propagation into shadow zones.

  20. On Risk Charges and Shadow Account Options in Pension Funds

    DEFF Research Database (Denmark)

    Jørgensen, Peter Løchte; Gatzert, Nadine

    This paper studies the economic implications of regulatory systems which allow equityholders of pension companies to not only charge a specific premium to compensate them for their higher risk (compared to policyholders), but also to accumulate these risk charges in a so-called shadow account...

  1. On Risk Charges and Shadow Account Options in Pension Funds

    DEFF Research Database (Denmark)

    Jørgensen, Peter Løchte; Gatzert, Nadine

    2015-01-01

    This paper studies the economic implications of regulatory systems which allow equityholders of pension companies to not only charge a specific premium to compensate them for their higher risk (compared to policyholders), but also to accumulate these risk charges in a so-called shadow account...

  2. Overestimation of Mach number due to probe shadow

    Energy Technology Data Exchange (ETDEWEB)

    Gosselin, J. J.; Thakur, S. C.; Tynan, G. R. [Center for Energy Research, University of California at San Diego, San Diego, California 92093 (United States); Sears, S. H. [Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin, 53706 (United States); McKee, J. S.; Scime, E. E. [Department of Physics, West Virginia University, Morgantown, West Virginia 26506 (United States)

    2016-07-15

    Comparisons of the plasma ion flow speed measurements from Mach probes and laser induced fluorescence were performed in the Controlled Shear Decorrelation Experiment. We show the presence of the probe causes a low density geometric shadow downstream of the probe that affects the current density collected by the probe in collisional plasmas if the ion-neutral mean free path is shorter than the probe shadow length, L{sub g} = w{sup 2} V{sub drift}/D{sub ⊥}, resulting in erroneous Mach numbers. We then present a simple correction term that provides the corrected Mach number from probe data when the sound speed, ion-neutral mean free path, and perpendicular diffusion coefficient of the plasma are known. The probe shadow effect must be taken into account whenever the ion-neutral mean free path is on the order of the probe shadow length in linear devices and the open-field line region of fusion devices.

  3. EFFECT OF SHADOWING AND MULTIPATH FADING ON THE ...

    African Journals Online (AJOL)

    The traditional macro-only network have been proved ineffective when communication signal is required for users located in the cell edge and a certain distance away ... Numerical simulation carried out for the macro-femto heterogeneous network using MATLAB shows how the effect of fading and shadowing was reduced.

  4. Physician shadowing by college students: what do patients think?

    Science.gov (United States)

    Bing-You, Robert G; Hayes, Victoria M; Skolfield, Jennifer L

    2014-03-14

    The objective of this study is to determine patients' perceptions of physician shadowing by college students. Thirty-two patients who agreed to have a college student shadow their physician participated in semi-structured interviews during July and August 2013 at two outpatient family medicine centers. Qualitative techniques were utilized to analyze the transcripts of the patient interviews and identify common themes. The majority of patients (78.1%) felt the college student had a neutral effect on their visit and denied having concerns about confidentiality (87.5%). No patient felt that having the college student present affected their ability to maintain a trusting relationship with their physician. Three themes emerged from the qualitative analysis: benefits to students, willing participation and sensitive issues. Most patients (78.5%) recognized that the student was in college or was a premedical student. The overwhelming majority of patients stated that they would have a college student shadow their physician again in the future. Despite concerns raised by other authors about the possible negative effects of physician shadowing by college students, this study shows that patients feel the impact to be primarily neutral and that there are many perceived benefits to both student and patient.

  5. Congress Puts 'Shadow' Pricing Of MS Drugs in the Spotlight.

    Science.gov (United States)

    Silverman, Ed

    2017-10-01

    Lawmakers asked seven companies to explain not only "skyrocketing prices," but a practice known as shadow pricing in which a drugmaker increases the price of an existing medicine to match the price hike or higher price set for a new drug launched by another company.

  6. Perspective: Dynamic Shadowing Growth and its Energy Applications

    Directory of Open Access Journals (Sweden)

    Yiping eZhao

    2014-09-01

    Full Text Available The unique features of dynamic shadowing growth (DSG in structural and compositional design of nanomaterials are discussed. Their recent applications in energy storage, fuel cell, and solar energy conversion have been reviewed briefly. Future directions for applying DSG nanostructures in renewable energy applications are presented.

  7. Assessment of Multipath and Shadowing Effects on UHF Band in ...

    African Journals Online (AJOL)

    Sultan

    3Department of Information and Communication Science, University of florin. Abstract. Ultra-high frequency (UHF) bands are ... Radio propagation, Terrain features. ATBU Journal of Environmental Technology 10, 1, June 2017. Page 2. Assessment of Multipath and Shadowing Effects on UHF Band in Built-Up Environments.

  8. Shadow-Based Vehicle Detection in Urban Traffic

    Directory of Open Access Journals (Sweden)

    Manuel Ibarra-Arenado

    2017-04-01

    Full Text Available Vehicle detection is a fundamental task in Forward Collision Avoiding Systems (FACS. Generally, vision-based vehicle detection methods consist of two stages: hypotheses generation and hypotheses verification. In this paper, we focus on the former, presenting a feature-based method for on-road vehicle detection in urban traffic. Hypotheses for vehicle candidates are generated according to the shadow under the vehicles by comparing pixel properties across the vertical intensity gradients caused by shadows on the road, and followed by intensity thresholding and morphological discrimination. Unlike methods that identify the shadow under a vehicle as a road region with intensity smaller than a coarse lower bound of the intensity for road, the thresholding strategy we propose determines a coarse upper bound of the intensity for shadow which reduces false positives rates. The experimental results are promising in terms of detection performance and robustness in day time under different weather conditions and cluttered scenarios to enable validation for the first stage of a complete FACS.

  9. Shadow Formation at Preschool from a Socio-materiality Perspective

    Science.gov (United States)

    Impedovo, Maria Antonietta; Delserieys-Pedregosa, Alice; Jégou, Corinne; Ravanis, Konstantinos

    2017-06-01

    The paper is set in socio-material farming to offer a way of conceptualising actions and interactions of children in preschool involved in the understanding of scientific concepts. A model of early science education about the physical phenomena of shadow formation is implemented in group work in a French context. The research involved 44 children (13 females and 31 males) of 5-6 years old. The research design was organised in three video recording steps: pre-test, teaching session and post-test. We focus on the analysis of nine teaching sessions to investigate children's `understanding' of shadow formation. A descriptive and qualitative approach was used. In particular, we have identified three main categories (the interaction of the children with the tools, the embodiment and verbal dimension)—with respective indicators—to perform the analysis. From the results, all the categories explored seem to influence each other: all material, human and social dimensions contribute to the children's understanding of shadow formation. Also we have identified some elements that can serve as a potential source of improvement of the teaching session on shadow formation. Finally, the research provides insights on how to improve science activities in preschool with the aim of supporting early understanding of physical phenomena.

  10. Shadow Capital: The Democratization of College Preparatory Education

    Science.gov (United States)

    Cipollone, Kristin; Stich, Amy E.

    2017-01-01

    In this article, we examine the manifestation and consequences of shadow capital within two public, urban, nonselective, college preparatory-designated high schools serving exclusively nondominant students. Informed by three years of ethnographic data, we argue that the transference of a historically elite college preparatory education from…

  11. Aerial Photography as a Tool to Document Coastal Change Along Eroding Shorelines in Northern Alaska

    Science.gov (United States)

    Gibbs, A.; Richmond, B. M.; Nolan, M.

    2014-12-01

    Chronic and widespread coastal erosion along the northern coast of Alaska is threatening traditional lifestyles, sensitive ecosystems, energy and defense related infrastructure, and large tracts of Native Alaskan, State, and Federally managed land. Recent USGS historical shoreline position studies have documented shoreline change rates along most of northern Alaska for the period from 1947 to circa 2000. Rates vary from an erosional high of -18.6 m/yr along vulnerable bluffed coasts, to accretion up to +10.9 m/yr along prograding sand-rich coasts (average rate for entire study area is -1.4 m/yr). The historical analysis gives valuable information regarding long-term rates of change but does not provide details on the timing and processes driving the change. Oblique and vertical aerial photography contains valuable coastal information on such things as bluff failure mechanisms, presence or absence of shorefast ice, beach characteristics including erosional scarps and ice-push ridges, wrack lines produced during storm surge events, and habitat identification. Recent advances in digital photogrammetry applied to oblique aerial photography can be used to construct high quality DEMs at a relatively low cost. Repeat aerial surveys and resultant DEM construction serve as a potential monitoring tool that can be used to quantify volumetric change, and, if conducted frequently enough, provide insights into the mechanisms responsible for coastal change in the Arctic. We provide examples from a few selected sites in northern Alaska where oblique aerial photography has been used to better understand coastal change in remote and threatened areas.

  12. Filling gaps in cultural heritage documentation by 3D photography

    Science.gov (United States)

    Schuhr, W.; Lee, J. D.

    2015-08-01

    This contribution promotes 3D photography as an important tool to obtain objective object information. Keeping mainly in mind World Heritage documentation as well as Heritage protection, it is another intention of this paper, to stimulate the interest in applications of 3D photography for professionals as well as for amateurs. In addition this is also an activity report of the international CIPA task group 3. The main part of this paper starts with "Digging the treasure of existing international 3D photography". This does not only belong to tangible but also to intangible Cultural Heritage. 3D photography clearly supports the recording, the visualization, the preservation and the restoration of architectural and archaeological objects. Therefore the use of 3D photography in C.H. should increase on an international level. The presented samples in 3D represent a voluminous, almost partly "forgotten treasure" of international archives for 3D photography. The next chapter is on "Promoting new 3D photography in Cultural Heritage". Though 3D photographs are a well-established basic photographic and photogrammetric tool, even suited to provide "near real" documentation, they are still a matter of research and improvement. Beside the use of 3D cameras even single lenses cameras are very much suited for photographic 3D documentation purposes in Cultural Heritage. Currently at the Faculty of Civil Engineering of the University of Applied Sciences Magdeburg-Stendal, low altitude aerial photography is exposed from a maximum height of 13m, using a hand hold carbon telescope rod. The use of this "huge selfie stick" is also an (international) recommendation, to expose high resolution 3D photography of monuments under expedition conditions. In addition to the carbon rod recently a captive balloon and a hexacopter UAV- platform is in use, mainly to take better synoptically (extremely low altitude, ground truth) aerial photography. Additional experiments with respect to "easy

  13. The Shadow Knows: Using Shadows to Investigate the Structure of the Pretransitional Disk of HD 100453

    Energy Technology Data Exchange (ETDEWEB)

    Long, Zachary C.; Fernandes, Rachel B.; Sitko, Michael [Department of Physics, University of Cincinnati, Cincinnati, OH 45221 (United States); Wagner, Kevin [Department of Astronomy/Steward Observatory, The University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Muto, Takayuki [Division of Liberal Arts, Kogakuin University, 1-24-2 Nishi-Shinjuku, Shinjuku-ku, Tokyo, 163-8677 (Japan); Hashimoto, Jun; Oh, Daehyon; Tamura, Motohide; Yang, Yi [National Astronomical Observatory of Japan, 2-21-1, Osawa, Mitaka, Tokyo, 181-8588 (Japan); Follette, Katherine [Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, Stanford, CA 94305 (United States); Grady, Carol A. [Eureka Scientific, 2452 Delmer Street, Suite 100, Oakland CA 96402 (United States); Fukagawa, Misato [Division of Particle and Astrophysical Science, Graduate School of Science, Nagoya University, Nagoya (Japan); Hasegawa, Yasuhiro [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Kluska, Jacques; Kraus, Stefan [University of Exeter Astrophysics Group, School of Physics, Stocker Road, Exeter, Devon EX4 4QL (United Kingdom); Mayama, Satoshi [Department of Astronomical Science, The Graduate University for Advanced Studies (SOKENDAI), Shonan Village, Hayama, Kanagawa 240-0193 (Japan); McElwain, Michael W. [Exoplanets and Stellar Astrophysics Laboratory, Code 667, NASA’s Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Uyama, Taichi [Department of Astronomy and RESCUE, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-0033 (Japan); Wisniewski, John P. [Homer L. Dodge Department of Physics, University of Oklahoma, Norman, OK 73071 (United States)

    2017-03-20

    We present Gemini Planet Imager polarized intensity imagery of HD 100453 in Y , J , and K 1 bands that reveals an inner gap (9–18 au), an outer disk (18–39 au) with two prominent spiral arms, and two azimuthally localized dark features that are also present in Spectro-Polarimetric High-contrast Exoplanet REsearch (SPHERE) total intensity images. Spectral energy distribution fitting further suggests that the radial gap extends to 1 au. The narrow, wedge-like shape of the dark features appears similar to predictions of shadows cast by an inner disk that is misaligned with respect to the outer disk. Using the Monte Carlo radiative transfer code HOCHUNCK3D, we construct a model of the disk that allows us to determine its physical properties in more detail. From the angular separation of the features, we measure the difference in inclination between the disks (45°) and their major axes, PA = 140° east of north for the outer disk, and 100° for the inner disk. We find an outer-disk inclination of 25° ± 10° from face-on, in broad agreement with the Wagner et al. measurement of 34°. SPHERE data in J and H bands indicate a reddish disk, which indicates that HD 100453 is evolving into a young debris disk.

  14. Moving toward Visual Literacy: Photography as a Language of Teacher Inquiry

    Science.gov (United States)

    Moran, Mary Jane; Tegano, Deborah W.

    2005-01-01

    This article presents one portrayal of the role of photography as a language of teacher inquiry. To inform teachers' use of photography, the first part of the article presents a brief historical perspective of photography's role in the study of human behavior in the fields of visual anthropology, visual sociology, photojournalism, and media…

  15. 15 CFR 265.42 - Photography for advertising or commercial purposes; advertising and soliciting.

    Science.gov (United States)

    2010-01-01

    ... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Photography for advertising or... COLLINS, COLORADO Buildings and Grounds § 265.42 Photography for advertising or commercial purposes... approval. Photography for advertising and commercial purposes may be conducted only with the written...

  16. Exposing Students to Repeat Photography: Increasing Cultural Understanding on a Short-Term Study Abroad

    Science.gov (United States)

    Lemmons, Kelly K.; Brannstrom, Christian; Hurd, Danielle

    2014-01-01

    Traditionally, repeat photography has been used to analyze land cover change. This paper describes how repeat photography may be used as a tool to enhance the short-term study abroad experience by facilitating cultural interaction and understanding. We present evidence from two cases and suggest a five-step repeat photography method for educators…

  17. 78 FR 52209 - Proposed Fee Schedule for Commercial Filming and Still Photography Permits

    Science.gov (United States)

    2013-08-22

    ... Forest Service Proposed Fee Schedule for Commercial Filming and Still Photography Permits AGENCY: Office... commercial filming and still photography conducted on public lands under their jurisdiction. The proposed fee schedule would establish land-use fees for commercial filming and still photography that are consistent for...

  18. 78 FR 58342 - Proposed Fee Schedule for Commercial Filming and Still Photography Permits

    Science.gov (United States)

    2013-09-23

    ... Forest Service Proposed Fee Schedule for Commercial Filming and Still Photography Permits AGENCY: Office... proposed fee schedule for commercial filming and still photography conducted on public lands under their... commercial filming and still photography that are consistent for the National Park Service, the U.S. Fish and...

  19. 78 FR 52087 - Commercial Filming and Similar Projects and Still Photography Activities

    Science.gov (United States)

    2013-08-22

    ... Service 50 CFR Part 27 RIN 1024-AD30 Commercial Filming and Similar Projects and Still Photography... similar projects and certain still photography activities. DATES: The rule is effective September 23, 2013... of equipment present, and other factors. Authorizes commercial filming and still photography permits...

  20. Medical Illustration--The Impact of Photography on its History.

    Science.gov (United States)

    Ollerenshaw, Robert

    2000-01-01

    Looks at some of the important stepping stones in the evolution of medical illustration from the anatomists and artists of the fourteenth and fifteenth centuries, through the introduction of the camera obscura in the eighteenth century, and on to the advent of photography. (Author/MM)

  1. [Retino-photography--screening method for diabetic retinopathy].

    Science.gov (United States)

    Davidescu, Livia; Ignat, Florica; Preda, Mirela; Damian, Carmen

    2005-01-01

    The paper presents the modern screening method for diabetic retinopathy--the retino-photography. We are presenting our experience on this issue, regarding the patients with diabetes retinopathy examined in Diabetic Eye Department, Ophthalmology Clinic Craiova, between October 2002-June 2005.

  2. Quantitative photography of intermittency in surface wave turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Wright, W.; Budakian, R.; Putterman, S.J. [Univ. of California, Los Angeles, CA (United States)

    1997-12-31

    At high amplitudes of excitation surface waves on water distribute their energy according to a Kolmogorov type of turbulent power spectrum. We have used diffusing light photography to measure the power spectrum and to quantify the presence of large structures in the turbulent state.

  3. Photographic documentation, a practical guide for non professional forensic photography.

    Science.gov (United States)

    Ozkalipci, Onder; Volpellier, Muriel

    2010-01-01

    Forensic photography is essential for documentation of evidence of torture. Consent of the alleged victim should be sought in all cases. The article gives information about when and how to take pictures of what as well as image authentication, audit trail, storage, faulty pictures and the kind of camera to use.

  4. Effects of Photography on Acquisition of Sculpture Skills among ...

    African Journals Online (AJOL)

    FIRST LADY

    photography were extended into medicine, archeology, science, sport, agriculture, art and education. Learners' academic performances have been increased through .... Religious Studies among Junior Secondary Students in Remo Local. Government Area of Ogun State. M.A. Thesis, Obafemi Awolowo. University, Ile-Ife.

  5. The impact of photography in a developing economy | Irivwieri ...

    African Journals Online (AJOL)

    ... as an image–making process is not quite appreciated by budding artists and professionals as an art form. This study is thus aimed at advancing photography as a versatile creative medium of expression and a veritable tool for research and skill acquisition for employment generation irrespective of one's chosen career.

  6. 179 The Impact of Photography in a Developing Economy

    African Journals Online (AJOL)

    Nekky Umera

    creative art. In consequence, both professionals and amateurs are encouraged to take to photography not only as a recreative venture but as an employment generation medium for sustainable growth in a developing economy. Keywords: Communication, optical image, daguerreotype, digital, automatic recording, light.

  7. The impact of photography in a developing economy | Irivwieri ...

    African Journals Online (AJOL)

    creative art. In consequence, both professionals and amateurs are encouraged to take to photography not only as a recreative venture but as an employment generation medium for sustainable growth in a developing economy. Keywords - Communication, optical image, daguerreotype, digital, automatic recording, light.

  8. 3-Dimensional Building Details from Aerial Photography for Internet Maps

    Directory of Open Access Journals (Sweden)

    Philipp Meixner

    2011-04-01

    Full Text Available This paper introduces the automated characterization of real estate (real property for Internet mapping. It proposes a processing framework to achieve this task from vertical aerial photography and associated property information. A demonstration of the feasibility of an automated solution builds on test data from the Austrian City of Graz. Information is extracted from vertical aerial photography and various data products derived from that photography in the form of a true orthophoto, a dense digital surface model and digital terrain model, and a classification of land cover. Maps of cadastral property boundaries aid in defining real properties. Our goal is to develop a table for each property with descriptive numbers about the buildings, their dimensions, number of floors, number of windows, roof shapes, impervious surfaces, garages, sheds, vegetation, presence of a basement floor, and other descriptors of interest for each and every property of a city. From aerial sources, at a pixel size of 10 cm, we show that we have obtained positional accuracies in the range of a single pixel, an accuracy of areas in the 10% range, floor counts at an accuracy of 93% and window counts at 86% accuracy. We also introduce 3D point clouds of facades and their creation from vertical aerial photography, and how these point clouds can support the definition of complex facades.

  9. Digital Photography as a Tool to Measure School Cafeteria Consumption

    Science.gov (United States)

    Swanson, Mark

    2008-01-01

    Background: Assessing actual consumption of school cafeteria meals presents challenges, given recall problems of children, the cost of direct observation, and the time constraints in the school cafeteria setting. This study assesses the use of digital photography as a technique to measure what elementary-aged students select and actually consume…

  10. Silver nanoparticles from silver halide photography to plasmonics

    CERN Document Server

    Tani, Tadaaki

    2015-01-01

    This book provides systematic knowledge and ideas on nanoparticles of Ag and related materials. While Ag and metal nanoparticles are essential for plasmonics, silver halide (AgX) photography relies to a great extent on nanoparticles of Ag and AgX which have the same crystal structure and have been studied extensively for many years. This book has been written to combine the knowledge of nanoparticles of Ag and related materials in plasmonics and AgX photography in order to provide new ideas for metal nanoparticles in plasmonics. Chapters 1–3 of this book describe the structure and formation of nanoparticles of Ag and related materials. Systematic descriptions of the structure and preparation of Ag, Au, and noble-metal nanoparticles for plasmonics are followed by and related to those of nanoparticles of Ag and AgX in AgX photography. Knowledge of the structure and preparation of Ag and AgX nanoparticles in photography covers nanoparticles with widely varying sizes, shapes, and structures, and formation proce...

  11. Conservation Photography as Environmental Education: Focus on the Pedagogues

    Science.gov (United States)

    Farnsworth, Bruce Evan

    2011-01-01

    This research examines the genre of conservation photography as a legitimate and highly relevant pedagogical enterprise well poised amid the proliferation of digital media and environmental crises. This small-scale qualitative study closely follows the work of four professional photojournalists. This research asserts that the professional…

  12. Improved Processing, Analysis and Use of Historical Photography

    Science.gov (United States)

    2010-10-01

    3.1.1 Image Restoration and Enhancement .......................................................... 7 3.1.2 Photogrammetry Using Historical Photos...Comparison of film scanning resolutions ............................................................. 18 Figure 6. Stereo pair of 1950 photographs with...conventional and digital photogrammetry . This page left blank intentionally. 1 1.0 EXECUTIVE SUMMARY Historical aerial photography is

  13. Ophthalmoscopy versus non-mydriatic fundus photography in the ...

    African Journals Online (AJOL)

    The contribution of non-mydriatic fundus photography in the detection of diabetic retinopathy before and after dilatation of the pupils in black diabetics was investigated and compared with direct ophthalmoscopy. Eighty-six patients were examined and good-quality photographs were obtained for 54,7% of eyes before and ...

  14. Encouraging Creativity in Mathematics and Science through Photography

    Science.gov (United States)

    Munakata, Mika; Vaidya, Ashwin

    2012-01-01

    Based on the results of a survey of the science and mathematics students at our university, we observed that students do not consider mathematics and science to be creative endeavors, though the traditional artistic disciplines rank high in this regard. To address this problem in perception, the authors used photography as a means to encourage…

  15. Studying place practices and consumption through volunteer-employed photography

    DEFF Research Database (Denmark)

    Pristed Nielsen, Helene; Møller, Karina Torp

    2016-01-01

    upon such choices. Additionally, we argue that the employed data collection techniques, involving a combination of volunteer-employed photography with participants’ comments on their own photos and information about their socio-demographic profile, constitute a particularly apt approach for shedding...

  16. A Spreadsheet-based GIS tool for planning aerial photography

    Science.gov (United States)

    The U.S.EPA's Pacific Coastal Ecology Branch has developed a tool which facilitates planning aerial photography missions. This tool is an Excel spreadsheet which accepts various input parameters such as desired photo-scale and boundary coordinates of the study area and compiles ...

  17. Drawing on Dynamic Local Knowledge through Student-Generated Photography

    Science.gov (United States)

    Coles-Ritchie, Marilee; Monson, Bayley; Moses, Catherine

    2015-01-01

    In this research, the authors explored how teachers using student-generated photography draw on local knowledge. The study draws on the framework of funds of knowledge to highlight the assets marginalized students bring to the classroom and the need for culturally relevant pedagogy to address the needs of a diverse public school population. The…

  18. Effects of Photography on Acquisition of Sculpture Skills among ...

    African Journals Online (AJOL)

    The study investigated the effects of photography on acquisition of sculpture skills among Junior Secondary School Students in Osun State. Forty students were randomly selected from two schools. The two schools were purposefully selected from fifty secondary schools in Ife Central Local Government Council Area of Osun ...

  19. Open Courses, Informal, Social Learning and Mobile Photography

    Science.gov (United States)

    McGuire, Mark

    2016-01-01

    This paper provides an overview of MOOCs (Massive Open Online Courses) and contextualizes them within the broader trends of open, informal and mobile learning. It then discuss Phonar Nation, a free, open, non-credit five-week photography course that was offered twice in 2014 using mobile media to reach youth from 12-18 years of age. The author…

  20. Kite Aerial Photography (KAP) as a Tool for Field Teaching

    Science.gov (United States)

    Sander, Lasse

    2014-01-01

    Kite aerial photography (KAP) is proposed as a creative tool for geography field teaching and as a medium to approach the complexity of readily available geodata. The method can be integrated as field experiment, surveying technique or group activity. The acquired aerial images can instantaneously be integrated in geographic information systems…

  1. Repeat photography as a tool for detecting and monitoring historical ...

    African Journals Online (AJOL)

    Repeat photography was used to illustrate long-term changes occurring in coastal habitats in the Western Cape, South Africa. Hi storic images were sourced from books and theses, the public and subject specialists, and repeat photographs were then taken from the same perspectives. Visible changes could be categorised ...

  2. Pupil Mortification: Digital Photography and Identity Construction in Classroom Assessment

    Science.gov (United States)

    Crossouard, Barbara

    2012-01-01

    Cultural theorists have illuminated how photographic images contribute to autobiographical remembering and identity formation. This has new significance given that digital photography now allows personal images to circulate rapidly amongst peer groups. Taking these insights into classroom contexts, this paper draws on recent case-study data to…

  3. Photography and Writing: Alternative Ways of Learning for ESL Students

    Science.gov (United States)

    Friesen, Helen Lepp

    2012-01-01

    To writing, painting, drawing, and photography as artistic media, the author would like to add teaching as a creative endeavor as well. Especially in a classroom where English is not the first language for many students, the writing teacher needs to be creative with assignments and activities that address nontraditional ways of learning. Her…

  4. Informed consent for medical photography in Nigerian surgical ...

    African Journals Online (AJOL)

    Background: The aim of this study is to assess the current practice of informed consent for medical photography in the Nigerian surgical practice and how it compares to international best practices. Methods: Self-administered questionnaires were distributed to consenting surgeons attending two major surgical conferences.

  5. Participatory Photography: Can It Help Adult Learners Develop Agency?

    Science.gov (United States)

    Yang, Kyung-Hwa

    2014-01-01

    This article draws on a participatory photography project conducted with 10 socioeconomically disadvantaged adult learners for six weeks within the framework of production pedagogy. Throughout the project, the participants took photographs about their lives in response to three prompts that I gave: (1) take photographs of people that are important…

  6. Leave-one-out Kernel Optimization for Shadow Detection and Removal.

    Science.gov (United States)

    Yago Vicente, Tomas F; Hoai, Minh; Samaras, Dimitris

    2017-04-06

    The objective of this work is to detect shadows in images. We pose this as the problem of labeling image regions, where each region corresponds to a group of superpixels. To predict the label of each region, we train a kernel Least-Squares Support Vector Machine(LSSVM) for separating shadow and non-shadow regions. The parameters of the kernel and the classifier are jointly learned to minimize the leave-one-out cross validation error. Optimizing the leave-one-out cross validation error is typically difficult, but it can be done efficiently in our framework. Experiments on two challenging shadow datasets, UCF and UIUC, show that our region classifier outperforms more complex methods. We further enhance the performance of the region classifier by embedding it in a Markov Random Field(MRF) framework and adding pairwise contextual cues. This leads to a method that outperforms the state-of-the-art for shadow detection. In addition we propose a new method for shadow removal based on region relighting. For each shadow region we use a trained classifier to identify a neighboring lit region of the same material. Given a pair of lit-shadow regions we perform a region relighting transformation based on histogram matching of luminance values between the shadow region and the lit region. Once a shadow is detected, we demonstrate that our shadow removal approach produces results that outperform the state of the art by evaluating our method using a publicly available benchmark dataset.

  7. Filling gaps in cultural heritage documentation by 3D photography

    Directory of Open Access Journals (Sweden)

    W. Schuhr

    2015-08-01

    Full Text Available This contribution promotes 3D photography as an important tool to obtain objective object information. Keeping mainly in mind World Heritage documentation as well as Heritage protection, it is another intention of this paper, to stimulate the interest in applications of 3D photography for professionals as well as for amateurs. In addition this is also an activity report of the international CIPA task group 3. The main part of this paper starts with “Digging the treasure of existing international 3D photography”. This does not only belong to tangible but also to intangible Cultural Heritage. 3D photography clearly supports the recording, the visualization, the preservation and the restoration of architectural and archaeological objects. Therefore the use of 3D photography in C.H. should increase on an international level. The presented samples in 3D represent a voluminous, almost partly “forgotten treasure” of international archives for 3D photography. The next chapter is on “Promoting new 3D photography in Cultural Heritage”. Though 3D photographs are a well-established basic photographic and photogrammetric tool, even suited to provide “near real” documentation, they are still a matter of research and improvement. Beside the use of 3D cameras even single lenses cameras are very much suited for photographic 3D documentation purposes in Cultural Heritage. Currently at the Faculty of Civil Engineering of the University of Applied Sciences Magdeburg-Stendal, low altitude aerial photography is exposed from a maximum height of 13m, using a hand hold carbon telescope rod. The use of this “huge selfie stick” is also an (international recommendation, to expose high resolution 3D photography of monuments under expedition conditions. In addition to the carbon rod recently a captive balloon and a hexacopter UAV- platform is in use, mainly to take better synoptically (extremely low altitude, ground truth aerial photography. Additional

  8. Shadow Detection Based on Regions of Light Sources for Object Extraction in Nighttime Video.

    Science.gov (United States)

    Lee, Gil-Beom; Lee, Myeong-Jin; Lee, Woo-Kyung; Park, Joo-Heon; Kim, Tae-Hwan

    2017-03-22

    Intelligent video surveillance systems detect pre-configured surveillance events through background modeling, foreground and object extraction, object tracking, and event detection. Shadow regions inside video frames sometimes appear as foreground objects, interfere with ensuing processes, and finally degrade the event detection performance of the systems. Conventional studies have mostly used intensity, color, texture, and geometric information to perform shadow detection in daytime video, but these methods lack the capability of removing shadows in nighttime video. In this paper, a novel shadow detection algorithm for nighttime video is proposed; this algorithm partitions each foreground object based on the object's vertical histogram and screens out shadow objects by validating their orientations heading toward regions of light sources. From the experimental results, it can be seen that the proposed algorithm shows more than 93.8% shadow removal and 89.9% object extraction rates for nighttime video sequences, and the algorithm outperforms conventional shadow removal algorithms designed for daytime videos.

  9. Shadow casted by a Konoplya-Zhidenko rotating non-Kerr black hole

    Science.gov (United States)

    Wang, Mingzhi; Chen, Songbai; Jing, Jiliang

    2017-10-01

    We have investigated the shadow of a Konoplya-Zhidenko rotating non-Kerr black hole with an extra deformation parameter. The spacetime structure arising from the deformed parameter affects sharply the black hole shadow. With the increase of the deformation parameter, the size of the shadow of black hole increase and its shape becomes more rounded for arbitrary rotation parameter. The D-shape shadow of black hole emerges only in the case ablack hole shadow possesses a cusp shape with small eye lashes in the cases with a>M, and the shadow becomes less cuspidal with the increase of the deformation parameter. Our result show that the presence of the deformation parameter yields a series of significant patterns for the shadow casted by a Konoplya-Zhidenko rotating non-Kerr black hole.

  10. Determinants of the Shadow Economy in the Czech Regions: A Region-Level Study

    Directory of Open Access Journals (Sweden)

    Buček Jakub

    2017-09-01

    Full Text Available This paper investigates the size and development of the shadow economy in the Czech Republic on the state-level base over the 2005-2014 period. The multiple indicators multiple causes (MIMIC model is used to assess the estimation of the shadow economy size. I investigate how labour market, number of people with at least one distraint, and the burden of taxation might contribute to the existence of the shadow economy. While the former two are important determinants of the shadow economy, I find no evidence to prove any significant impact of distraints on the shadow economy size. As for the country’s particular regions, I find that those surrounding big cities, especially Prague, have, on average, a smaller shadow economy size, whereas regions in the borderlands (former Sudetenland suffer from a larger shadow economy.

  11. Shadow of a Kerr-Sen dilaton-axion Black Hole

    CERN Document Server

    Dastan, Sara; Soroushfar, Saheb

    2016-01-01

    We analyze the shadow of charged stationary axially symmetric space-time (Kerr-Sen dilaton-axion black hole). This black hole is defined by a mass $M$, a spin $a$ and $r_{\\alpha}=Q^{2}/M$, where $Q$ is the electric charge. Shadows are investigated in two conditions, i) for an observer at infinity in vacuum and ii) for an observer at infinity in the presence of plasma with radial power-low density. In vacuum, the shadow of this black hole depends on charge and spin parameter. We can see that, increasing electric charge, $Q$ decreases the size of shadow. Also, increasing spin parameter $a$ decreases the size of shadow. However, in existence of plasma, parameter of plasma like refraction index, $n$, playing an important role on shadows. In fact, decreasing refraction index decreases the size of shadow.

  12. A Soft Shadow Detection Method Based on MRF for Remote Sensing Images

    Directory of Open Access Journals (Sweden)

    Pengwei Li

    2015-01-01

    Full Text Available Shadows limit many remote sensing applications such as classification, target detection, and change detection. Most current shadow detection methods utilize the histogram threshold of spectral characteristics to distinguish the shadows and nonshadows directly, called “hard binary shadow.” Obviously, the performance of threshold-based methods heavily rely on the selected threshold. Simultaneously, these threshold-based methods do not take any spatial information into account. To overcome these shortcomings, a soft shadow description method is developed by introducing the concept of opacity into shadow detection, and MRF-based shadow detection method is proposed in order to make use of neighborhood information. Experiments on remote sensing images have shown that the proposed method can obtain more accurate detection results.

  13. Standing in the shadow of Snowdonia.

    Science.gov (United States)

    Durham, Nick

    2010-04-01

    Leaving the site in a better condition than when they left it, and minimising the development's impact on the local scenery, reflecting the area's history and natural heritage in the design, and exploiting the stunning location and views to provide a relaxing, therapeutic care environment, were among the goals for architects Nightingale Associates when they drew up plans for the Ysbyty Alltwen community hospital, spectacularly positioned high on the foothills of Snowdonia. Speaking at a recent New London Architecture (NLA) seminar examining "Creating sustainable healthcare buildings", Nightingale Associates architect and studio director Nick Durham described the project's evolution.

  14. [Photography in plastic surgery: practices, uses and legislation].

    Science.gov (United States)

    de Runz, A; Simon, E; Brix, M; Sorin, T; Brengard-Bresler, T; Pineau, V; Guyon, G; Claudot, F

    2015-02-01

    Photography in plastic surgery is omnipresent. Through its various uses, it may present both ethical and forensic risks. The objective of this study is to analyze the use of medical photography by the plastic surgeon, the perception of this use by the patient, and consequence of such use. A questionnaire about the use of medical photography was assessed to 629 plastic surgeons. A questionnaire was given to patients, about their perception of the use of photography by their surgeon. One hundred and seventy-six surgeon's questionnaires and 93 patient's questionnaires were analyzed. For 97.7% of the responding surgeons, the proportion of patients refusing to be photographed was less then 1/20. The objective of the photography was especially medicolegal for 62.5% of the surgeons, especially for following the patient progress (87.5%), partially for the formation (72.1%), partially for scientific publications (57.8%) and not at all for the personal publicity (73.1%). Surgeons often share his photographs with others surgeons (71.1%), sometimes with others medical personnel (48.8%). The security and the access to photographs were determined to be correct for 67.6% of the surgeons and perfect for 23.3%. In total, 17.2% of the surgeons obtained a written consent, 41.4% obtained an oral consent, and 38.5% did not request patient consent. It was found that 48.3% of the surgeons and 40.2% of the patients think that the right to the photographic images belong to the patient. Medical photographs expose the plastic surgeon to medico-legal risks. He must know and follow the law in order to prevent eventual legal proceedings. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  15. Riddles in the Dark: Imaging Inside Mercury's Permanently Shadowed Craters

    Science.gov (United States)

    Ernst, C. M.; Chabot, N. L.; Denevi, B. W.; Nair, H.; Deutsch, A. N.; Murchie, S. L.; Robinson, M. S.; Blewett, D. T.; Head, J. W.; Harmon, J. K.; Neumann, G. A.; Solomon, S. C.

    2013-12-01

    Numerous lines of evidence independently point to the presence of water ice in Mercury's polar regions: Earth-based radar shows radar-bright regions; Mariner 10 and MESSENGER Mercury Dual Imaging System (MDIS) images reveal that these regions are permanently (south polar region) or persistently (north polar region) shadowed; neutron spectrometry indicates hydrogen-rich material; thermal models support the presence of water ice; and Mercury Laser Altimeter (MLA) reflectance measurements at 1064 nm show high and low reflectance deposits consistent in location to where models predict surface and buried water ice, respectively. Throughout 2013, MESSENGER executed a campaign dedicated to imaging the permanently shadowed crater floors of Mercury's north polar region using sunlight scattered from nearby terrain. The campaign makes use of the broadband clear filter (central wavelength 700 nm, bandwidth 600 nm) of the MDIS wide-angle camera (WAC) to target and image radar-bright areas within all host craters > 10 km in diameter under multiple lighting conditions. To date, MESSENGER has imaged the interiors of nearly 20 craters that host radar-bright deposits, including the largest such deposits near the north pole that are likely to host surface water ice. The images reveal a variety of surface morphologies, ranging from the smooth crater floor of the fresh Kandinsky crater, to the moderately cratered floor of Tolkien crater, and to the battered floor of Prokofiev crater, in which the permanently shadowed region does not differ morphologically from the rest of the crater floor. Thus, no distinct morphology is identified in association with polar deposits, and craters hosting such material span the typical range of degradation states relative to their illuminated counterparts. MDIS images also reveal albedo differences in craters with floors not fully in permanent shadow. Prokofiev provides a special environment for viewing a radar- and MLA-bright region suspected to host

  16. A LA SOMBRA DEL ESTADO: COMUNALIZACIÓN INDÍGENA EN PARAJES DE LA PRE CORDILLERA DE RÍO NEGRO, ARGENTINA / In the shadow of the state: Indian communalization in sites from the Rio Negro province pre Cordillera, Argentina

    Directory of Open Access Journals (Sweden)

    Lorena Cañuqueo

    2015-12-01

    Full Text Available Nos proponemos analizar un proceso de comunalización situado en parajes rurales de la cuenca del arroyo Comallo, provincia de Río Negro. En agosto de 2011 se conformó formalmente allí la comunidad mapuche Newen Ñuke Mapu que pasó a integrarse a las comunidades denominadas “nuevas” en la provincia, por contraste con aquellas consideradas “tradicionales”. Nuestro argumento es que esa novedad no es tal, sino que subyace un proceso de comunalización de larga duración que ha estado en permanente disputa con políticas estatales atomizadoras. En este sentido, se trata de un colectivo que se ha desarrollado a la sombra del estado argentino. Comenzaremos con un recorrido histórico en función de ubicar este caso en el proceso de incorporación del pueblo mapuche al estado nacional. A continuación analizamos el proceso de comunalización en tres escenarios históricos anclados en crisis de diferente tipo. 1 El presente que retoma la conformación de la comunidad mapuche. A partir de este aparecen como instancias de referencia consideradas fundantes de lo colectivo dos momentos históricos anteriores. 2 1984, periodo en el que se conforman las cooperativas laneras, entre otras formas de organización indígena. 3 1930, crisis que marcó el avance de la propiedad privada en la zona y que implicó estrategias de visibilización y demanda dirigidas al estado.  AbstractIn this article we intend to analyze a process of communalization located in the rural areas of the province of Río Negro. In August 2011 the Mapuche community Newen Ñuke Mapu came formally into existence. Since then on it became one more of the “new” indigenous communities in contrast to those acknowledge as “traditional”. Our argument is that there is no such novelty but there is an underlying long term process of communalization that has been in constant dispute with state policies. In this sense, we describe it as a grouping that has developed at the shadow of

  17. The Reel Thing. Creative Photography. Art Education: Art Cft 7 6681.01, CM Art 1 6693.01.

    Science.gov (United States)

    Farnsworth, William; Beckman, Louise

    This creative photography quinmester curriculum guide was written to enable the student to use photography in a wide range of art forms. The student will gain an understanding of how photography is used in the fields of commercial and fine art. The introduction to photography as a unique art form includes a brief history of creative and…

  18. Digital Cover Photography for Estimating Leaf Area Index (LAI in Apple Trees Using a Variable Light Extinction Coefficient

    Directory of Open Access Journals (Sweden)

    Carlos Poblete-Echeverría

    2015-01-01

    Full Text Available Leaf area index (LAI is one of the key biophysical variables required for crop modeling. Direct LAI measurements are time consuming and difficult to obtain for experimental and commercial fruit orchards. Devices used to estimate LAI have shown considerable errors when compared to ground-truth or destructive measurements, requiring tedious site-specific calibrations. The objective of this study was to test the performance of a modified digital cover photography method to estimate LAI in apple trees using conventional digital photography and instantaneous measurements of incident radiation (Io and transmitted radiation (I through the canopy. Leaf area of 40 single apple trees were measured destructively to obtain real leaf area index (LAID, which was compared with LAI estimated by the proposed digital photography method (LAIM. Results showed that the LAIM was able to estimate LAID with an error of 25% using a constant light extinction coefficient (k = 0.68. However, when k was estimated using an exponential function based on the fraction of foliage cover (ff derived from images, the error was reduced to 18%. Furthermore, when measurements of light intercepted by the canopy (Ic were used as a proxy value for k, the method presented an error of only 9%. These results have shown that by using a proxy k value, estimated by Ic, helped to increase accuracy of LAI estimates using digital cover images for apple trees with different canopy sizes and under field conditions.

  19. Digital Cover Photography for Estimating Leaf Area Index (LAI) in Apple Trees Using a Variable Light Extinction Coefficient

    Science.gov (United States)

    Poblete-Echeverría, Carlos; Fuentes, Sigfredo; Ortega-Farias, Samuel; Gonzalez-Talice, Jaime; Yuri, Jose Antonio

    2015-01-01

    Leaf area index (LAI) is one of the key biophysical variables required for crop modeling. Direct LAI measurements are time consuming and difficult to obtain for experimental and commercial fruit orchards. Devices used to estimate LAI have shown considerable errors when compared to ground-truth or destructive measurements, requiring tedious site-specific calibrations. The objective of this study was to test the performance of a modified digital cover photography method to estimate LAI in apple trees using conventional digital photography and instantaneous measurements of incident radiation (Io) and transmitted radiation (I) through the canopy. Leaf area of 40 single apple trees were measured destructively to obtain real leaf area index (LAID), which was compared with LAI estimated by the proposed digital photography method (LAIM). Results showed that the LAIM was able to estimate LAID with an error of 25% using a constant light extinction coefficient (k = 0.68). However, when k was estimated using an exponential function based on the fraction of foliage cover (ff) derived from images, the error was reduced to 18%. Furthermore, when measurements of light intercepted by the canopy (Ic) were used as a proxy value for k, the method presented an error of only 9%. These results have shown that by using a proxy k value, estimated by Ic, helped to increase accuracy of LAI estimates using digital cover images for apple trees with different canopy sizes and under field conditions. PMID:25635411

  20. Digital cover photography for estimating leaf area index (LAI) in apple trees using a variable light extinction coefficient.

    Science.gov (United States)

    Poblete-Echeverría, Carlos; Fuentes, Sigfredo; Ortega-Farias, Samuel; Gonzalez-Talice, Jaime; Yuri, Jose Antonio

    2015-01-28

    Leaf area index (LAI) is one of the key biophysical variables required for crop modeling. Direct LAI measurements are time consuming and difficult to obtain for experimental and commercial fruit orchards. Devices used to estimate LAI have shown considerable errors when compared to ground-truth or destructive measurements, requiring tedious site-specific calibrations. The objective of this study was to test the performance of a modified digital cover photography method to estimate LAI in apple trees using conventional digital photography and instantaneous measurements of incident radiation (Io) and transmitted radiation (I) through the canopy. Leaf area of 40 single apple trees were measured destructively to obtain real leaf area index (LAI(D)), which was compared with LAI estimated by the proposed digital photography method (LAI(M)). Results showed that the LAI(M) was able to estimate LAI(D) with an error of 25% using a constant light extinction coefficient (k = 0.68). However, when k was estimated using an exponential function based on the fraction of foliage cover (f(f)) derived from images, the error was reduced to 18%. Furthermore, when measurements of light intercepted by the canopy (Ic) were used as a proxy value for k, the method presented an error of only 9%. These results have shown that by using a proxy k value, estimated by Ic, helped to increase accuracy of LAI estimates using digital cover images for apple trees with different canopy sizes and under field conditions.

  1. Shadow-Shielding Compensation for Moving Sources Detection

    Science.gov (United States)

    Coulon, Romain; Dumazert, Jonathan

    2017-07-01

    To monitor radioactivity emitted by a vehicle such as a pedestrian, a car, a train, or a truck, radiation portal monitors (RPMs) are commonly employed. It has been noted that these RPM suffer from a shadow-shielding effect when the source is transported by a dense and large vehicle such as a truck or a train. While methods using databases are listed as state of the art, we have developed an approach based on a state model, ensuring a gain in performance and flexibility. This new study presents a technique applied to RPM, efficiently compensating the shadow-shielding effect. A simulation study has been performed to highlight the efficiency and reliability of the method.

  2. Shadow Areas Robust Matching Among Image Sequence in Planetary Landing

    Science.gov (United States)

    Ruoyan, Wei; Xiaogang, Ruan; Naigong, Yu; Xiaoqing, Zhu; Jia, Lin

    2017-01-01

    In this paper, an approach for robust matching shadow areas in autonomous visual navigation and planetary landing is proposed. The approach begins with detecting shadow areas, which are extracted by Maximally Stable Extremal Regions (MSER). Then, an affine normalization algorithm is applied to normalize the areas. Thirdly, a descriptor called Multiple Angles-SIFT (MA-SIFT) that coming from SIFT is proposed, the descriptor can extract more features of an area. Finally, for eliminating the influence of outliers, a method of improved RANSAC based on Skinner Operation Condition is proposed to extract inliers. At last, series of experiments are conducted to test the performance of the approach this paper proposed, the results show that the approach can maintain the matching accuracy at a high level even the differences among the images are obvious with no attitude measurements supplied.

  3. Wake models developed during the Wind Shadow project

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, S.; Ott, S.; Pena, A.; Berg, J.; Nielsen, M.; Rathmann, O.; Joergensen, H.

    2011-11-15

    The Wind Shadow project has developed and validated improved models for determining the wakes losses, and thereby the array efficiency of very large, closely packed wind farms. The rationale behind the project has been that the existing software has been covering these types of wind farms poorly, both with respect to the densely packed turbines and the large fetches needed to describe the collective shadow effects of one farm to the next. Further the project has developed the necessary software for the use of the models. Guidelines with recommendations for the use of the models are included in the model deliverables. The project has been carried out as a collaborative project between Risoe DTU, DONG, Vattenfall, DNV and VESTAS, and it has been financed by energinet.dk grant no. 10086. (Author)

  4. Andrew Beatty, A shadow falls; In the heart of Java.

    OpenAIRE

    Andrew Beatty; Edwin Wieringa; Michael Peletz; Pujo Semedi

    2010-01-01

    In this feature we highlight a recently launched book. We invite specialists in the field to comment on the book, and we invite the author to respond to their comments. In this issue we focus on Andrew Beatty's, A shadow falls; In the heart of Java. Those invited to comment on the book are Puja Semedi, Michael Peletz and Edwin Wieiringa. Registered readers may participate in the debate.

  5. Andrew Beatty, A shadow falls; In the heart of Java.

    Directory of Open Access Journals (Sweden)

    Andrew Beatty

    2010-09-01

    Full Text Available In this feature we highlight a recently launched book. We invite specialists in the field to comment on the book, and we invite the author to respond to their comments. In this issue we focus on Andrew Beatty's, A shadow falls; In the heart of Java. Those invited to comment on the book are Puja Semedi, Michael Peletz and Edwin Wieiringa. Registered readers may participate in the debate.

  6. We Three (My echo, my shadow and me)

    OpenAIRE

    Veator, Valerie E.

    2015-01-01

    We Three (My echo, my shadow and me) presents a tripartite work that exercises forms of tracing, imbedding, concealing and revealing across painting, video, and installation. Inspired by Jacques Rivette’s 1974 film Celine and Julie Go Boating, We Three examines perception and subjectivity in today’s screenic culture. We Three draws out modes transference in the form of an echoed, displaced transmission as it exists within and between specific artworks. The three parts are installed as echoes ...

  7. Shadow Banking – Developments in Times of Financial Crisis

    Directory of Open Access Journals (Sweden)

    Bogdan Munteanu

    2016-01-01

    The paper considers the following entities and activities, without limitation to or completenessof viewpoints: finance companies, asset backed financial instruments, structured investments,financing vehicles, money market funds, asset managers, credit hedge funds and venture capital,providing characteristics of shadow banking and their economic functions relative to the classicbanking system, as they pose a systemic risk due to asymmetric information and gaps created inmatching liquidity tenures with duration, by using synthetic leverage finance.

  8. SHADOW DETECTION FROM VERY HIGH RESOLUTON SATELLITE IMAGE USING GRABCUT SEGMENTATION AND RATIO-BAND ALGORITHMS

    Directory of Open Access Journals (Sweden)

    N. M. S. M. Kadhim

    2015-03-01

    Full Text Available Very-High-Resolution (VHR satellite imagery is a powerful source of data for detecting and extracting information about urban constructions. Shadow in the VHR satellite imageries provides vital information on urban construction forms, illumination direction, and the spatial distribution of the objects that can help to further understanding of the built environment. However, to extract shadows, the automated detection of shadows from images must be accurate. This paper reviews current automatic approaches that have been used for shadow detection from VHR satellite images and comprises two main parts. In the first part, shadow concepts are presented in terms of shadow appearance in the VHR satellite imageries, current shadow detection methods, and the usefulness of shadow detection in urban environments. In the second part, we adopted two approaches which are considered current state-of-the-art shadow detection, and segmentation algorithms using WorldView-3 and Quickbird images. In the first approach, the ratios between the NIR and visible bands were computed on a pixel-by-pixel basis, which allows for disambiguation between shadows and dark objects. To obtain an accurate shadow candidate map, we further refine the shadow map after applying the ratio algorithm on the Quickbird image. The second selected approach is the GrabCut segmentation approach for examining its performance in detecting the shadow regions of urban objects using the true colour image from WorldView-3. Further refinement was applied to attain a segmented shadow map. Although the detection of shadow regions is a very difficult task when they are derived from a VHR satellite image that comprises a visible spectrum range (RGB true colour, the results demonstrate that the detection of shadow regions in the WorldView-3 image is a reasonable separation from other objects by applying the GrabCut algorithm. In addition, the derived shadow map from the Quickbird image indicates

  9. Preparing students for clerkship: a resident shadowing program.

    Science.gov (United States)

    Turner, Simon R; White, Jonathan; Poth, Cheryl; Rogers, W Todd

    2012-09-01

    The preparation of medical students for clerkship has been criticized, in terms of both students understanding of their new role as clinical trainees and their ability to carry out that role. To begin to address this gap, the authors report the development, implementation, and assessment of a novel program in which first-year medical students shadow first-year residents during their clinical duties. The program matches each student to a single resident, whom they shadow for several hours, once per month, for eight months. In the programs inaugural year (2009-10), 83 student-resident pairs participated; over 70% responded to pre- and post-intervention questionnaires, which included an 18-item preparedness scale. The authors used those responses to evaluate the program. Compared to students in a control group, the students in the program assessed themselves as better prepared to learn in a clinical setting. The low-cost student-resident shadowing program described in this article provided an early and structured introduction to the clinical environment, which may help prepare students for the transition into clerkship.

  10. COMPUTER-AIDED DETECTION OF ACINAR SHADOWS IN CHEST RADIOGRAPHS

    Directory of Open Access Journals (Sweden)

    Tao Xu

    2013-05-01

    Full Text Available Despite the technological advances in medical diagnosis, accurate detection of infectious tuberculosis (TB still poses challenges due to complex image features and thus infectious TB continues to be a public health problem of global proportions. Currently, the detection of TB is mainly conducted visually by radiologists examining chest radiographs (CXRs. To reduce the backlog of CXR examination and provide more precise quantitative assessment, computer-aided detection (CAD systems for potential lung lesions have been increasingly adopted and commercialized for clinical practice. CADs work as supporting tools to alert radiologists on suspected features that could have easily been neglected. In this paper, an effective CAD system aimed for acinar shadow regions detection in CXRs is proposed. This system exploits textural and photometric features analysis techniques which include local binary pattern (LBP, grey level co-occurrence matrix (GLCM and histogram of oriented gradients (HOG to analyze target regions in CXRs. Classification of acinar shadows using Adaboost is then deployed to verify the performance of a combination of these techniques. Comparative study in different image databases shows that the proposed CAD system delivers consistent high accuracy in detecting acinar shadows.

  11. The Influence of Cast Shadows on the Detection of Three-Dimensional Curved Contour Structure.

    Science.gov (United States)

    Khuu, Sieu K; Honson, Vanessa J; Challinor, Kirsten L

    2016-04-01

    Cast shadows have been shown to provide an effective ordinal cue to the depth position of objects. In the present study, two experiments investigated the effectiveness of cast shadows in facilitating the detection of spatial contours embedded in a field of randomly placed elements. In Experiment 1, the separation between the cast shadow and the contour was systematically increased to effectively signal different contour depth positions (relative to background elements), and this was repeated for patterns in which the lighting direction was above and from below. Increasing the shadow separation improved contour detection performance, but the degree to which sensitivity changed was dependent on the lighting direction. Patterns in which the light was from above were better detected than patterns in which the lighting direction was from below. This finding is consistent with the visual system assuming a "light-from-above rule" when processing cast shadows. In Experiment 2, we examined the degree to which changing the shape of the cast shadow (by randomly jittering the position of local cast shadow elements) affected the ability of the visual system to rely on the cast shadow to cue the depth position of the contour. Consistent with a coarse scale analysis, we find that cast shadows remained an effective depth cue even at large degrees of element jitter. Our findings demonstrate that cast shadows provide an effective means of signaling depth, which aids the process of contour integration, and this process is largely tolerant of local variations in lighting direction. © The Author(s) 2016.

  12. Evaluating the Effects of Shadow Detection on QuickBird Image Classification and Spectroradiometric Restoration

    Directory of Open Access Journals (Sweden)

    Marvin E. Bauer

    2013-09-01

    Full Text Available Shadows in high resolution imagery create significant problems for urban land cover classification and environmental application. We first investigated whether shadows were intrinsically different and hypothetically possible to separate from each other with ground spectral measurements. Both pixel-based and object-oriented methods were used to evaluate the effects of shadow detection on QuickBird image classification and spectroradiometric restoration. In each method, shadows were detected and separated either with or without histogram thresholding, and subsequently corrected with a k-nearest neighbor algorithm and a linear correlation correction. The results showed that shadows had distinct spectroradiometric characteristics, thus, could be detected with an optimal brightness threshold and further differentiated with a scene-based near infrared ratio. The pixel-based methods generally recognized more shadow areas and with statistically higher accuracy than the object-oriented methods. The effects of the prior shadow thresholding were not statistically significant. The accuracy of the final land cover classification, after accounting for the shadow detection and separation, was significantly higher for the pixel-based methods than for the object-oriented methods, although both achieved similar accuracy for the non-shadow classes. Both radiometric restoration algorithms significantly reduced shadow areas in the original satellite images.

  13. SOCIO-ECONOMIC NATURE OF SHADOW ECONOMY AND CAUSES OF ITS DEVELOPMENT IN ENTREPRENEURSHIP

    Directory of Open Access Journals (Sweden)

    I. Mazur

    2017-01-01

    Full Text Available The socio-economic nature of the shadow economy is revealed. The shadow economy has both positive and negative signs for the society; the possibility for the population to survive in conditions of economic crisis, reducing transaction costs authors refer to positive signs, and the destructive economic development to negative. The common (prohibitions and restrictions and partial (high tax burden and inefficient system of its administration; numerous bureaucratic procedures; mistrust to the government institutions and the judiciary; corruption in all levels of the governance, etc. causes of the shadow economy in entrepreneurship are disclosed. It is argued that the shadow economy is neither a sector nor a certain part of the legal economy, it can be in any sector of the legal economy closely interlaced with it, and therefore its limits cannot be clearly identified (determine in the formal economy. The shadow economy is not possible to determine especially in the information society. The categories of the shadow economy and its structuring are suggested. It has been researched the historical roots of the shadow economy spread in entrepreneurship, and lie in the shadow of public-private partnership which carries interests of "civil servant-entrepreneurs" and allows to manage state resources and control market. Therefore, the shadow policy creates favorable conditions for the entrepreneurs to work in the shadow. At the same time, access to the shadow entails stricter regulation by the state. It is proved that corruption is a part of the shadow economy, not an independent phenomenon, so they should be research comprehensively and systematically. Instead of overcoming the shadow economy and its component - corruption has been suggested to establish favorable business environment for their unfavorable existence, that is to carry out deshadowing of the economy.

  14. The Importance of Photography as an Information Support in Event Management (Case Event of Anugerah Bambu Indonesia 2013)

    OpenAIRE

    Anwar Basalamah; Maria Pia Adiati

    2013-01-01

    This study aims to investigate the potential of media photography as a means of support in an event practice, analyze photography as data source in identifying the event practice, explore photography as documentation that helps in event execution, examine photography as visual language that supports the event management. From the case of an event organized by Anugerah Bambu Indonesia 2013, results from the study finds that photography has an added value as a data source, documenta...

  15. The Importance of Photography as an Information Support in Event Management (Case Event of Anugerah Bambu Indonesia 2013)

    OpenAIRE

    Basalamah, Anwar; Adiati, Maria Pia

    2013-01-01

    This study aims to investigate the potential of media photography as a means of support in an event practice, analyze photography as data source in identifying the event practice, explore photography as documentation that helps in event execution, examine photography as visual language that supports the event management. From the case of an event organized by Anugerah Bambu Indonesia 2013, results from the study finds that photography has an added value as a data source, documentation, and vi...

  16. The shadow of a doubt ? Evidence for perceptuo-motor linkage during auditory and audiovisual close shadowing

    Directory of Open Access Journals (Sweden)

    Lucie eScarbel

    2014-06-01

    Full Text Available One classical argument in favor of a functional role of the motor system in speech perception comes from the close shadowing task in which a subject has to identify and to repeat as quickly as possible an auditory speech stimulus. The fact that close shadowing can occur very rapidly and much faster than manual identification of the speech target is taken to suggest that perceptually-induced speech representations are already shaped in a motor-compatible format. Another argument is provided by audiovisual interactions often interpreted as referring to a multisensory-motor framework. In this study, we attempted to combine these two paradigms by testing whether the visual modality could speed motor response in a close-shadowing task. To this aim, both oral and manual responses were evaluated during the perception of auditory and audio-visual speech stimuli, clear or embedded in white noise. Overall, oral responses were faster than manual ones, but it also appeared that they were less accurate in noise, which suggests that motor representations evoked by the speech input could be rough at a first processing stage. In the presence of acoustic noise, the audiovisual modality led to both faster and more accurate responses than the auditory modality. No interaction was however observed between modality and response. Altogether, these results are interpreted within a two-stage sensory-motor framework, in which the auditory and visual streams are integrated together and with internally generated motor representations before a final decision may be available.

  17. CERN at Arles: LHC featured in prestigious photography festival

    CERN Multimedia

    Jordan Juras

    2011-01-01

    Six photographs of the LHC experiment are being featured in this year’s Rencontres d’Arles photography festival. Simon Norfolk’s series, The LHC: the spirit of enquiry, was chosen as part of an exhibition celebrating 30 years of photography at the New York Times Magazine.   Simon Norfolk’s series "The LHC: the spirit of enquiry" on display at the Rencontres d'Arles festival. The photographs were originally taken in October 2006, when Norfolk was sent on an assignment to a ‘little known’ laboratory in Switzerland. “When I came to CERN, nobody I knew had ever heard of the place,” explains Norfolk. “Everybody I spoke to when I came back said, ‘You’ve been where? You’ve done what?’” Kathy Ryan, New York Times Magazine photo editor, sent Norfolk to ‘capture something new’. He describes Ryan’s assignments...

  18. Standardized facial photography of cleft patients: just fit the grid?

    Science.gov (United States)

    Vegter, F; Hage, J J

    2000-09-01

    The objective results of craniofacial surgery are usually evaluated by comparing pre- and postoperative photographs. To allow for optimal comparison, these photographs should be of constant and reproducible lay-out and quality. For this, various techniques to standardize photography have been suggested. A review of the literature on standardization of medical photography is presented. The advantages and disadvantages of standardizing techniques are evaluated. The difficulty to achieve standardization in cleft patients is illustrated using clinical photographs. Our personal protocol is presented as it tries to optimize comparability of photographs. Use of a grid or cephalostat will not lead to comparable photographs in cleft patients. Personal protocols also have shortcomings, but they offer reproducible and comparable results. A personal effort of the photographer is essential to adjust any allegedly standardizing protocol to the individual patient. Photographs are only as good as the photographer. True standardization of facial photographs is a utopia in cleft patients.

  19. Landscape concept in photography: from Luigi Ghirri to Antonio Ottomanelli

    Directory of Open Access Journals (Sweden)

    Teodora Malavenda

    2014-05-01

    Full Text Available In the 80s of the last century the Italian photography, like other art forms, reflected the political, economic and cultural changes of the Nation. It was the time of a new documentary photography that investigated the transformation of the urban areas. Within this process the landscape was the subject of a new interpretation. In 2013 this process of documentation was worked out again, but in a modern way, by Antonio Ottomanelli. In his project "Collateral Landscape", he took pictures in different cities of the world such as Kabul, Baghdad, Sadr City, Herat, Dokan, New York, Gaza City. Distant places and only apparently different from each other. In fact, all of them have been destroyed by war or, in the case of New York, have been target of a terrorist attack.

  20. Comparison Among Methods of Retinopathy Assessment (CAMRA) Study: Smartphone, Nonmydriatic, and Mydriatic Photography.

    Science.gov (United States)

    Ryan, Martha E; Rajalakshmi, Ramachandran; Prathiba, Vijayaraghavan; Anjana, Ranjit Mohan; Ranjani, Harish; Narayan, K M Venkat; Olsen, Timothy W; Mohan, Viswanathan; Ward, Laura A; Lynn, Michael J; Hendrick, Andrew M

    2015-10-01

    We compared smartphone fundus photography, nonmydriatic fundus photography, and 7-field mydriatic fundus photography for their abilities to detect and grade diabetic retinopathy (DR). This was a prospective, comparative study of 3 photography modalities. Diabetic patients (n = 300) were recruited at the ophthalmology clinic of a tertiary diabetes care center in Chennai, India. Patients underwent photography by all 3 modalities, and photographs were evaluated by 2 retina specialists. The sensitivity and specificity in the detection of DR for both smartphone and nonmydriatic photography were determined by comparison with the standard method, 7-field mydriatic fundus photography. The sensitivity and specificity of smartphone fundus photography, compared with 7-field mydriatic fundus photography, for the detection of any DR were 50% (95% confidence interval [CI], 43-56) and 94% (95% CI, 92-97), respectively, and of nonmydriatic fundus photography were 81% (95% CI, 75-86) and 94% (95% CI, 92-96%), respectively. The sensitivity and specificity of smartphone fundus photography for the detection of vision-threatening DR were 59% (95% CI, 46-72) and 100% (95% CI, 99-100), respectively, and of nonmydriatic fundus photography were 54% (95% CI, 40-67) and 99% (95% CI, 98-100), respectively. Smartphone and nonmydriatic fundus photography are each able to detect DR and sight-threatening disease. However, the nonmydriatic camera is more sensitive at detecting DR than the smartphone. At this time, the benefits of the smartphone (connectivity, portability, and reduced cost) are not offset by the lack of sufficient sensitivity for detection of DR in most clinical circumstances. Copyright © 2015 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  1. Medical illustration. The impact of photography on its history.

    Science.gov (United States)

    Ollerenshaw, R

    2000-01-01

    In this article, developed from an oral presentation given at the thirty-seventh annual meeting of the B.P.A. in August, 1967 and first published in 1968 in the Journal of the Biological Photographic Association, some of the important stepping stones in the evolution of medical illustration are looked at--from the anatomists and artists of the fourteenth and fifteenth centuries, through the introduction of the camera obscura in the eighteenth century, and on to the advent of photography.

  2. Erosion control and watershed management by Spacelab photography

    Science.gov (United States)

    Koelbl, O.; Depury, P.

    1985-04-01

    The interpretability of false color Spacelab photographs for erosion control and water shed management was assessed using photos taken over Nepal and the Mount Everest Massif. The thematic interpretation was done by a geologist working in this region. Scale limitations, image reproduction, and filtering of the photographs are discussed. Results show that much information can be extracted using relatively simple means. Color infrared photography must be used since panchromatic imagery does not show enough detail.

  3. Exhibition of photography from the Estonian diaspora / Ellu Maar

    Index Scriptorium Estoniae

    Maar, Ellu, 1982-

    2010-01-01

    Näitus "Photography from the Estonian Diaspora / Väliseesti foto" Kumu Kunstimuuseumis 8.10.-19.11.2010, kuraatorid Eha Komissarov ja Ellu Maar. Näitus tutvustas 1944. a. Eestist lahkunud või juba võõrsil sündinud fotograafide (Eric Soovere, Karl Hintzer, Priit Vesilind, Rein Välme jt.) loomingut ja valikut väliseesti fotoarhiividest

  4. Consumption and photography in Erwin Olaf: a contemporary perspective

    Directory of Open Access Journals (Sweden)

    Wilton Garcia

    2015-06-01

    Full Text Available Between consumption and photography, the aim of this paper is to present the Dutch photographer Erwin Olaf work with a visualty impactful. The methodological approach of a qualitative strategically reading is divided into three stages: observation, description and discussion from the photo series Fashion victms (2000. The contemporary studies serve as theoretical basis for the proposal of contemporary imagens. The resulting add a criticalconceptual discussion that enters the market-media current.

  5. Colposcopic photography of genital injury following sexual intercourse in adults.

    Science.gov (United States)

    Astrup, Birgitte Schmidt; Lauritsen, Jens; Thomsen, Jørgen Lange; Ravn, Pernille

    2013-03-01

    The aim of this study was to evaluate interpretations and the reproducibility of interpretations when looking at colposcopic photographs in a forensic setting, as well as discussing some of the dilemmas and pitfalls of forensic colposcopic photography. A total of 316 colposcopic photographs from 51 women taken on three occasions following consensual sexual intercourse, and 78 colposcopic photographs from 39 rape victims, were evaluated by four different observers. Photographs were taken in the same setting, by the same group of investigators, before and after application of toluidine blue dye. The overall Kappa-value for the four observers' judgment of lesion vs. no lesion was 0.41 which can be interpreted as moderate agreement. Intra-observer agreement was calculated for two of the observers looking at photographs with a 10 months' time-gap, and the Kappa-values were 0.41 and 0.52. Positive and negative predictive values of the photographs were 82 and 81 % respectively. This study demonstrates relatively poor reliability of colposcopic photography. Some would argue that this makes colposcopic photography a low-quality method of evaluation and that forensic science should aim for higher standards because of its use in court. Others would argue that as long as the limitations of a scientific method are acknowledged then it is still eligible for use. The moderate agreement and accuracy stresses the need for quality control in the gynecological part of a rape examination. Colposcopic photography also provides a good option for supervision and teaching in an ethically difficult setting. It strengthens the legal rights for both victim and perpetrator.

  6. Clinical photography in dermatology using smartphones: An overview

    Science.gov (United States)

    Ashique, K. T.; Kaliyadan, Feroze; Aurangabadkar, Sanjeev J.

    2015-01-01

    The smartphone is one of the biggest revolutions in the era of information technology. Its built in camera offers several advantages. Dermatologists, who handle a specialty that is inherently visual, are most benefited by this handy technology. Here in this article, we attempt to provide an overview of smartphone photography in clinical dermatology in order to help the dermatologist to get the best out of the available camera for clinical imaging and storage PMID:26009708

  7. Research on Quality Inspection Method of Digital Aerial Photography Results

    OpenAIRE

    Wang, Xiaojun; Li, Yanling; Liang, Yong; Zeng, Yanwei

    2010-01-01

    International audience; Photography is the main access to obtain geospatial information, the quality of the results will directly affect the follow-up results of the quality of surveying and mapping. Therefore, we need a comprehensive aerial photographic quality inspection results. Correct evaluation of the quality of digital images is an important but difficult to solve the research topic. Many of the current image quality evaluation mainly rely on the subjective judgments. With the rapid de...

  8. Mercury rotation period determined from Mariner 10 photography

    Science.gov (United States)

    Klaasen, K. P.

    1975-01-01

    The rotation period of Mercury has been determined to be 58.661 days by using high-resolution photography from the Mariner 10 mission. This value matches the period required for 3/2 synchronism with the orbital period (58.6462 days) within the 1-sigma errors assigned and is consistent with the latest values derived from radar and earth-based telescopic observations.

  9. Photography and interpretations of the word: art and education

    Directory of Open Access Journals (Sweden)

    Lucinea Aparecida de Rezende

    2013-04-01

    Full Text Available This paper analyzes images made and broadcasted by Foto Clube de Londrina (Londrina’s Photo Club in 2011. We aim to think over the imagery reading, specially photograph, at education scope. To achieve this target, we understood photography as something possible to be interpretated and also as a work of art. This way, we show that readers can be benefited by reading and rereading photographs, when they are seen along with the words reading.

  10. Clinical photography in dermatology using smartphones: An overview.

    Science.gov (United States)

    Ashique, K T; Kaliyadan, Feroze; Aurangabadkar, Sanjeev J

    2015-01-01

    The smartphone is one of the biggest revolutions in the era of information technology. Its built in camera offers several advantages. Dermatologists, who handle a specialty that is inherently visual, are most benefited by this handy technology. Here in this article, we attempt to provide an overview of smartphone photography in clinical dermatology in order to help the dermatologist to get the best out of the available camera for clinical imaging and storage.

  11. Clinical photography in dermatology using smartphones: An overview

    Directory of Open Access Journals (Sweden)

    K T Ashique

    2015-01-01

    Full Text Available The smartphone is one of the biggest revolutions in the era of information technology. Its built in camera offers several advantages. Dermatologists, who handle a specialty that is inherently visual, are most benefited by this handy technology. Here in this article, we attempt to provide an overview of smartphone photography in clinical dermatology in order to help the dermatologist to get the best out of the available camera for clinical imaging and storage

  12. Mountaineering and photography. Contacts between 1880 and 1940

    Directory of Open Access Journals (Sweden)

    Maria Andorno

    2014-12-01

    Full Text Available Since the second half of the nineteenth century, the photograph produced in high altitude mountain (mountaineering photography gives rise to peculiar images that do not belong to the tradition of landscape painting. Mountaineering is similar to the art of performance, if we talk about physical and mental commitment. Therefore, photos taken during the ascent of a peak shows both conceptual and formal values.

  13. Acceptance and perception of Nigerian patients to medical photography.

    Science.gov (United States)

    Adeyemo, W L; Mofikoya, B O; Akadiri, O A; James, O; Fashina, A A

    2013-12-01

    The aim of the study was to determine the acceptance and perception of Nigerian patients to medical photography. A self-administered questionnaire was distributed among Nigerian patients attending oral and maxillofacial surgery and plastic surgery clinics of 3 tertiary health institutions. Information requested included patients' opinion about consent process, capturing equipment, distribution and accessibility of medical photographs. The use of non-identifiable medical photographs was more acceptable than identifiable to respondents for all purposes (P = 0.003). Most respondents were favourably disposed to photographs being taken for inclusion in the case note, but opposed to identifiable photographs being used for other purposes most especially in medical websites and medical journals. Female respondents preferred non-identifiable medical photographs to identifiable ones (P = 0.001). Most respondents (78%) indicated that their consent be sought for each of the outline needs for medical photography. Half of the respondents indicated that identifiable photographs may have a negative effect on their persons; and the most commonly mentioned effects were social stigmatization, bad publicity and emotional/psychological effects. Most of the respondents preferred the use of hospital-owned camera to personal camera/personal camera-phone for their medical photographs. Most respondents (67.8%) indicated that they would like to be informed about the use of their photographs on every occasion, and 74% indicated that they would like to be informed of the specific journal in which their medical photographs are to be published. In conclusion, non-identifiable rather than identifiable medical photography is acceptable to most patients in the studied Nigerian environment. The use of personal camera/personal camera-phone should be discouraged as its acceptance by respondents is very low. Judicious use of medical photography is therefore advocated to avoid breach of principle of

  14. Standardized methods for photography in procedural dermatology using simple equipment.

    Science.gov (United States)

    Hexsel, Doris; Hexsel, Camile L; Dal'Forno, Taciana; Schilling de Souza, Juliana; Silva, Aline F; Siega, Carolina

    2017-04-01

    Photography is an important tool in dermatology. Reproducing the settings of before photos after interventions allows more accurate evaluation of treatment outcomes. In this article, we describe standardized methods and tips to obtain photographs, both for clinical practice and research procedural dermatology, using common equipment. Standards for the studio, cameras, photographer, patients, and framing are presented in this article. © 2017 The International Society of Dermatology.

  15. Digital dental photography. Part 2: Purposes and uses.

    Science.gov (United States)

    Ahmad, I

    2009-05-09

    Although the primary purpose of using digital photography in dentistry is for recording various aspects of clinical information in the oral cavity, other benefits also accrue. Detailed here are the uses of digital images for dento-legal documentation, education, communication with patients, dental team members and colleagues and for portfolios, and marketing. These uses enhance the status of a dental practice and improve delivery of care to patients.

  16. Non-standard photography methods in audiovisual journalism

    OpenAIRE

    Géla, František

    2015-01-01

    The aim of the diploma thesis "Non- standard photography methods in audiovisual journalism" is to present image and production methods that are used in television news and journalism - particularly those ones that defy standard methods. These methods appear, considering technological development and the endeavour of making neutral visual space of television journalism, more attractive. First chapter of the thesis presents television news, its history, characteristics, elements and typology of...

  17. Brand New Images? Implications of Instagram Photography for Place Branding

    Directory of Open Access Journals (Sweden)

    Åsa Thelander

    2017-12-01

    Full Text Available The aim of this article is to develop an understanding of what happens when Instagram photography is used for branding a place. Questions raised are which photographs are taken and published, does the practice result in novel ways of representing a place, and, in turn the image of a place. A practice approach to photography is used where focus is directed to the performative aspect of photography. Fifteen qualitative interviews were conducted with participants in an Instagram takeover project concerning their photographs. The study shows that adopting a communication strategy based on visual social media is dependent on the participants’ competencies and that it is embedded in everyday life. Moreover, the participants’ photographic practices were found to be influenced by social conventions, which resulted in the city being imagined differently by different participants. To use visual social media such as Instagram for branding purposes does not necessarily mean that novel images are generated, but that they are choreographed according to the conditions of Instagram as medium.

  18. Near-infrared transillumination photography of intraocular tumours.

    Science.gov (United States)

    Krohn, Jørgen; Ulltang, Erlend; Kjersem, Bård

    2013-10-01

    To present a technique for near-infrared transillumination imaging of intraocular tumours based on the modifications of a conventional digital slit lamp camera system. The Haag-Streit Photo-Slit Lamp BX 900 (Haag-Streit AG) was used for transillumination photography by gently pressing the tip of the background illumination cable against the surface of the patient's eye. Thus the light from the flash unit was transmitted into the eye, leading to improved illumination and image resolution. The modification for near-infrared photography was done by replacing the original camera with a Canon EOS 30D (Canon Inc) converted by Advanced Camera Services Ltd. In this camera, the infrared blocking filter was exchanged for a 720 nm long-pass filter, so that the near-infrared part of the spectrum was recorded by the sensor. The technique was applied in eight patients: three with anterior choroidal melanoma, three with ciliary body melanoma and two with ocular pigment alterations. The good diagnostic quality of the photographs made it possible to evaluate the exact location and extent of the lesions in relation to pigmented intraocular landmarks such as the ora serrata and ciliary body. The photographic procedure did not lead to any complications. We recommend near-infrared transillumination photography as a supplementary diagnostic tool for the evaluation and documentation of anteriorly located intraocular tumours.

  19. Partial shadowing detection based on equivalent thermal voltage monitoring for PV module diagnostics

    DEFF Research Database (Denmark)

    Sera, Dezso; Teodorescu, Remus; Rodriguez, Pedro

    2009-01-01

    Partial shadowing of photovoltaic systems can overproportionally reduce the energy yield and lead to early ageing and failure of the shadowed cells. Large area shadows are relatively easy to detect due to the eminent power reduction and decrease of fill factor. However, small area partial shadows...... in a larger system do not have a very obvious effect on the output power or fill factor of the PV array and can remain undetected, leading to failure. In this paper a method for detecting small area partial shadows, based on equivalent thermal voltage, is presented. A simplified expression of the equivalent...... thermal voltage is proposed, which increases the robustness against measurement errors and model limitations at low irradiation conditions. Experimental results confirm the high sensitivity of the method even to a relatively small area shadow, while showing very good robustness against increase in series...

  20. Fast Shadow Detection from a Single Image Using a Patched Convolutional Neural Network

    OpenAIRE

    Hosseinzadeh, Sepideh; Shakeri, Moein; Zhang, Hong

    2017-01-01

    In recent years, various shadow detection methods from a single image have been proposed and used in vision systems; however, most of them are not appropriate for the robotic applications due to the expensive time complexity. This paper introduces a fast shadow detection method using a deep learning framework, with a time cost that is appropriate for robotic applications. In our solution, we first obtain a shadow prior map with the help of multi-class support vector machine using statistical ...

  1. ANALYZING SPECTRAL CHARACTERISTICS OF SHADOW AREA FROM ADS-40 HIGH RADIOMETRIC RESOLUTION AERIAL IMAGES

    Directory of Open Access Journals (Sweden)

    Y.-T. Hsieh

    2016-06-01

    Full Text Available The shadows in optical remote sensing images are regarded as image nuisances in numerous applications. The classification and interpretation of shadow area in a remote sensing image are a challenge, because of the reduction or total loss of spectral information in those areas. In recent years, airborne multispectral aerial image devices have been developed 12-bit or higher radiometric resolution data, including Leica ADS-40, Intergraph DMC. The increased radiometric resolution of digital imagery provides more radiometric details of potential use in classification or interpretation of land cover of shadow areas. Therefore, the objectives of this study are to analyze the spectral properties of the land cover in the shadow areas by ADS-40 high radiometric resolution aerial images, and to investigate the spectral and vegetation index differences between the various shadow and non-shadow land covers. According to research findings of spectral analysis of ADS-40 image: (i The DN values in shadow area are much lower than in nonshadow area; (ii DN values received from shadowed areas that will also be affected by different land cover, and it shows the possibility of land cover property retrieval as in nonshadow area; (iii The DN values received from shadowed regions decrease in the visible band from short to long wavelengths due to scattering; (iv The shadow area NIR of vegetation category also shows a strong reflection; (v Generally, vegetation indexes (NDVI still have utility to classify the vegetation and non-vegetation in shadow area. The spectral data of high radiometric resolution images (ADS-40 is potential for the extract land cover information of shadow areas.

  2. A hardware architecture for real-time shadow removal in high-contrast video

    Science.gov (United States)

    Verdugo, Pablo; Pezoa, Jorge E.; Figueroa, Miguel

    2017-09-01

    Broadcasting an outdoor sports event at daytime is a challenging task due to the high contrast that exists between areas in the shadow and light conditions within the same scene. Commercial cameras typically do not handle the high dynamic range of such scenes in a proper manner, resulting in broadcast streams with very little shadow detail. We propose a hardware architecture for real-time shadow removal in high-resolution video, which reduces the shadow effect and simultaneously improves shadow details. The algorithm operates only on the shadow portions of each video frame, thus improving the results and producing more realistic images than algorithms that operate on the entire frame, such as simplified Retinex and histogram shifting. The architecture receives an input in the RGB color space, transforms it into the YIQ space, and uses color information from both spaces to produce a mask of the shadow areas present in the image. The mask is then filtered using a connected components algorithm to eliminate false positives and negatives. The hardware uses pixel information at the edges of the mask to estimate the illumination ratio between light and shadow in the image, which is then used to correct the shadow area. Our prototype implementation simultaneously processes up to 7 video streams of 1920×1080 pixels at 60 frames per second on a Xilinx Kintex-7 XC7K325T FPGA.

  3. Nuclear dependence of structure functions in the shadowing region of deep inelastic scattering

    Energy Technology Data Exchange (ETDEWEB)

    Berger, E.L.; Qiu, Jianwei

    1988-07-27

    A discussion of nuclear shadowing in deep inelastic lepton scattering is presented. We show that the parton recombination model suggests that shadowing should begin to occur at larger values of Bjorken x as A increases. This expectation as well as that of weak dependence on Q/sup 2/, and the trend of the x dependence of the shadowing phenomenon are consistent with recent data. Shadowing at small x is combined with nuclear bound state effects, responsible for nuclear dependence at larger x, to provide description of the A dependence of the structure function for the entire range of x. 21 refs., 5 figs.

  4. How to use 3D shadows for simple microscopy and vibrometry

    Science.gov (United States)

    Parikesit, Gea O. F.; Kusumaningtyas, Indraswari

    2017-07-01

    In 2014, we reported that shadows can be displayed in 3D using a stereoscopic setup. We now report that the 3D shadows can also be used to perform simple measurements, which are suitable for physics education in schools and colleges. Two different types of measurements are demonstrated, i.e. microscopy and vibrometry. Both types of measurements take advantage of the geometrical optics of the 3D shadows, where the 3D position of an object can be estimated using the coordinates of the colored light sources and the coordinates of the colored shadow images. We also include several student activities that can raise the students’ curiosity and capability.

  5. Pacman in the sky with shadows: the effect of cast shadows on the perceptual completion of occluded figures by chimpanzees and humans

    Directory of Open Access Journals (Sweden)

    Imura Tomoko

    2010-07-01

    Full Text Available Abstract Background Humans readily perceive whole shapes as intact when some portions of these shapes are occluded by another object. This type of amodal completion has also been widely reported among nonhuman animals and is related to pictorial depth perception. However, the effect of a cast shadow, a critical pictorial-depth cue for amodal completion has been investigated only rarely from the comparative-cognitive perspective. In the present study, we examined this effect in chimpanzees and humans. Results Chimpanzees were slower in responding to a Pacman target with an occluding square than to the control condition, suggesting that participants perceptually completed the whole circle. When a cast shadow was added to the square, amodal completion occurred in both species. On the other hand, however, critical differences between the species emerged when the cast shadow was added to the Pacman figure, implying that Pacman was in the sky casting a shadow on the square. The cast shadow prevented, to a significant extent, compulsory amodal completion in humans, but had no effect on chimpanzees. Conclusion These results suggest that cast shadows played a critical role in enabling humans to infer the spatial relationship between Pacman and the square. For chimpanzees, however, a cast shadow may be perceived as another "object". A limited role for cast shadows in the perception of pictorial depth has also been reported with respect to human cognitive development. Further studies on nonhuman primates using a comparative-developmental perspective will clarify the evolutionary origin of the role of cast shadows in visual perception.

  6. Robust Lane Sensing and Departure Warning under Shadows and Occlusions

    Directory of Open Access Journals (Sweden)

    Miguel Torres-Torriti

    2013-03-01

    Full Text Available A prerequisite for any system that enhances drivers’ awareness of road conditions and threatening situations is the correct sensing of the road geometry and the vehicle’s relative pose with respect to the lane despite shadows and occlusions. In this paper we propose an approach for lane segmentation and tracking that is robust to varying shadows and occlusions. The approach involves color-based clustering, the use of MSAC for outlier removal and curvature estimation, and also the tracking of lane boundaries. Lane boundaries are modeled as planar curves residing in 3D-space using an inverse perspective mapping, instead of the traditional tracking of lanes in the image space, i.e., the segmented lane boundary points are 3D points in a coordinate frame fixed to the vehicle that have a depth component and belong to a plane tangent to the vehicle’s wheels, rather than 2D points in the image space without depth information. The measurement noise and disturbances due to vehicle vibrations are reduced using an extended Kalman filter that involves a 6-DOF motion model for the vehicle, as well as measurements about the road’s banking and slope angles. Additional contributions of the paper include: (i the comparison of textural features obtained from a bank of Gabor filters and from a GMRF model; and (ii the experimental validation of the quadratic and cubic approximations to the clothoid model for the lane boundaries. The results show that the proposed approach performs better than the traditional gradient-based approach under different levels of difficulty caused by shadows and occlusions.

  7. Robust Lane Sensing and Departure Warning under Shadows and Occlusions

    Science.gov (United States)

    Tapia-Espinoza, Rodolfo; Torres-Torriti, Miguel

    2013-01-01

    A prerequisite for any system that enhances drivers' awareness of road conditions and threatening situations is the correct sensing of the road geometry and the vehicle's relative pose with respect to the lane despite shadows and occlusions. In this paper we propose an approach for lane segmentation and tracking that is robust to varying shadows and occlusions. The approach involves color-based clustering, the use of MSAC for outlier removal and curvature estimation, and also the tracking of lane boundaries. Lane boundaries are modeled as planar curves residing in 3D-space using an inverse perspective mapping, instead of the traditional tracking of lanes in the image space, i.e., the segmented lane boundary points are 3D points in a coordinate frame fixed to the vehicle that have a depth component and belong to a plane tangent to the vehicle's wheels, rather than 2D points in the image space without depth information. The measurement noise and disturbances due to vehicle vibrations are reduced using an extended Kalman filter that involves a 6-DOF motion model for the vehicle, as well as measurements about the road's banking and slope angles. Additional contributions of the paper include: (i) the comparison of textural features obtained from a bank of Gabor filters and from a GMRF model; and (ii) the experimental validation of the quadratic and cubic approximations to the clothoid model for the lane boundaries. The results show that the proposed approach performs better than the traditional gradient-based approach under different levels of difficulty caused by shadows and occlusions. PMID:23478598

  8. Large scale 20mm photography for range resources analysis in the Western United States. [Casa Grande, Arizona, Mercury, Nevada, and Mojave Desert

    Science.gov (United States)

    Tueller, P. T.

    1977-01-01

    Large scale 70mm aerial photography is a valuable supplementary tool for rangeland studies. A wide assortment of applications were developed varying from vegetation mapping to assessing environmental impact on rangelands. Color and color infrared stereo pairs are useful for effectively sampling sites limited by ground accessibility. They allow an increased sample size at similar or lower cost than ground sampling techniques and provide a permanent record.

  9. Between the idea and the reality falls the shadow

    OpenAIRE

    Hogan, Jennifer

    1998-01-01

    non-peer-reviewed The aim of this thesis was to thoroughly immerse myself into the liminal space that lingers between our initial thoughts and realised visions. The shadow, as it were, was the elusive subject I have chased since my childhood. It is an experience, it is the multitude of experiences that make up a lifetime, my driving force. In a literal sense, it is the darkness resulting from placing an agglomeration of matter in the path of light. This is where the idea meets ...

  10. Shadow Affect in Urban Digital (Post Screen) Art

    DEFF Research Database (Denmark)

    Toft, Tanya Søndergaard

    2014-01-01

    The paper considers an affective turn in artistic practices with interactive urban digital screen-based art that evokes a behavioral response in the audience, which I propose as a symptom of the post screen. I propose the affective experience as a mode of exploring presence in the artwork through...... “shadow affect”, as an alternative to experiencing self identification and representation. I argue that a phenomenological understanding is necessary in place of a techno-aesthetic perspective, which would allow for more nuanced understandings of human experience in our digital reality....

  11. How outliers become superstars: what shadow coaches do.

    Science.gov (United States)

    Sullivan, Kevin W

    2012-01-01

    Physicians who score low on patient satisfaction surveys usually don't know what they're doing (or not doing) to cause below-average ratings. Too often, the temporary improvement gained from books and seminars dissipates as providers return to overloaded schedules and variability in patient expectations. Shadow coaching has proved effective for motivated physicians seeking more patient visits, better risk management, and high marks on the payer metrics that will soon affect qualification for Accountable Care, Medical Home, and favorable reimbursement.

  12. Shadow based building extraction from single satellite image

    Science.gov (United States)

    Singh, Gurshamnjot; Jouppi, Mark; Zhang, Zhuoran; Zakhor, Avideh

    2015-03-01

    Automatic building extraction in satellite imagery is an important problem. Existing approaches typically involve stereo processing two or more satellite views of the same region. In this paper, we use shadow analysis coupled with line segment detection and texture segmentation to construct rectangular building approximations from a single satellite image. In addition, we extract building heights to construct a rectilinear height profile for a single region. We characterize the performance of the system in rural and urban regions of Jordan, Philippines, and Australia and demonstrate a detection rate of 76.2 - 86.1% and a false alarm rate of 26.5 - 40.1%.

  13. Asymptotic Ergodic Capacity Analysis of Composite Lognormal Shadowed Channels

    KAUST Repository

    Ansari, Imran Shafique

    2015-05-01

    Capacity analysis of composite lognormal (LN) shadowed links, such as Rician-LN, Gamma-LN, and Weibull-LN, is addressed in this work. More specifically, an exact closed-form expression for the moments of the end-to-end signal-to-noise ratio (SNR) of a single composite link transmission system is presented in terms of well- known elementary functions. Capitalizing on these new moments expressions, we present asymptotically tight lower bounds for the ergodic capacity at high SNR. All the presented results are verified via computer-based Monte-Carlo simulations. © 2015 IEEE.

  14. Regulatory elements of the floral homeotic gene AGAMOUS identified by phylogenetic footprinting and shadowing.

    Energy Technology Data Exchange (ETDEWEB)

    Hong, R. L., Hamaguchi, L., Busch, M. A., and Weigel, D.

    2003-06-01

    OAK-B135 In Arabidopsis thaliana, cis-regulatory sequences of the floral homeotic gene AGAMOUS (AG) are located in the second intron. This 3 kb intron contains binding sites for two direct activators of AG, LEAFY (LFY) and WUSCHEL (WUS), along with other putative regulatory elements. We have used phylogenetic footprinting and the related technique of phylogenetic shadowing to identify putative cis-regulatory elements in this intron. Among 29 Brassicaceae, several other motifs, but not the LFY and WUS binding sites previously identified, are largely invariant. Using reporter gene analyses, we tested six of these motifs and found that they are all functionally important for activity of AG regulatory sequences in A. thaliana. Although there is little obvious sequence similarity outside the Brassicaceae, the intron from cucumber AG has at least partial activity in A. thaliana. Our studies underscore the value of the comparative approach as a tool that complements gene-by-gene promoter dissection, but also highlight that sequence-based studies alone are insufficient for a complete identification of cis-regulatory sites.

  15. Light tries the expert eye: the introduction of photography in nineteenth-century macroscopic neuroanatomy.

    Science.gov (United States)

    de Rijcke, Sarah

    2008-01-01

    It is often argued that photography's scientific inauguration meaningfully coincided with a shift towards the ideal of mechanical objectivity. Values of disinterestedness and precision were readily attributed to photography and were cherished by the emerging field of neurology as well. However, after the publication of the first neuroanatomical atlas to contain photographs, Jules Bernard Luys' Iconographie Photographique des Centres Nerveux (1873), the use of photography in macroscopic neuroanatomy remained rare. The present article sketches this largely overlooked terrain of investigation and will expand on why in macroscopical neuroanatomy photography failed to offer a satisfactory alternative to drawing or engraving.

  16. Photography and sculpture: The multifaceted relation of sculpture to photography and new media in the light of the evolving concept of sculpture

    Directory of Open Access Journals (Sweden)

    Paulina Dzwonkowska

    2010-06-01

    Full Text Available The relationship between photography and sculpture, unlike the dialogue between the latter and painting, was long treated as a peripheral issue. Yet as early as the mid-20th century photography began to show potential that sculpture seemed to be lack. Aware of a large degree of overlap between the two forms of artistic expression, (e.g. with respect to materiality, spatiality, or accentuating frozen gestures sculptors did not leave sculpture for photography, but attempted to create works that were interdisciplinary in structure. The rise of interest in photography displayed by Polish sculptors was closely connected with the evolution of the concept of sculpture. In the mid-20th century artists creating traditional sculptures (understood as a solid or as a visually rendered spatial form began to experiment and cross the boundaries of well-established artistic tradition. The changes introduced enabled sculptors to interweave their field with other artistic disciplines, especially photography, even more closely. More and more frequently, sculpture started to establish multi-faceted relations with the new medium. At the beginning the potential of photography as a documentation tool was exploited. Then sculptors began to appreciate photography’s core values, using it to capture and preserve a given moment in time. Finally, they applied it in works that can be classified as close to hyperrealism. The employment of still newer materials and tools made the link between sculpture and photography inextricable, as can be shown through works of Polish artists.

  17. Shadow banking, relationship banking, and the economics of depression

    Directory of Open Access Journals (Sweden)

    Antonio Bianco

    2015-12-01

    Full Text Available The paper explores whether a theory of banks doing ‘finance through money creation’ implies a reconsideration of demand-side macro theory as well. To this aim, a simple methodological accounting model of the influence of financial markets over the real economy is presented. The model allows a tidy comparison of relationship and shadow banking, interpreted as alternative schemes of liquidity (not credit risk management. The model emphasizes the interdependencies in entrepreneurs’ animal spirits, liquidity risk management schemes adopted by financial institutions, and effective demand of households. The underlying idea is that fluctuations in the composition of property incomes trigger fluctuations in non-financial investment that, in turn, drive fluctuations in spending. The article finds that both relationship and shadow banking must have a pro-cyclical impact, and differences are essentially based on different liquidity risk management aggregate cost functions. The model developed here suggests that securitisation does not per se affect the financial sustainability of the growth process, but regulatory measures aimed at checking predatory lending and re-securitisation activities are needed to avoid possible adverse impacts on animal spirits. JEL codes: E44, G20, O16.

  18. Racing the Moon’s shadow with Concorde 001

    CERN Document Server

    Léna, Pierre

    2015-01-01

    This is the unique story of  observing a total solar exlipse for no less than 74 consecutive minutes. On the summer morning of June 30, 1973, the Sun rises on the Canary Islands. But it is strangely indented by the Moon. The eclipse of the century has just begun. From the west, the lunar shadow rushes to the African coast at a velocity of over 2000 kilometers per hour. Astronomers on the ground will enjoy seven short minutes of total eclipse to study the solar corona - too short for Pierre Lena and seven scientists who board the Concorde 001 prototype, an extraordinary plane to become the first commercial supersonic aircraft. With André Turcat as chief pilot and a crew of five, at 17000 m altitude, the aircraft remains in the lunar shadow for 74 minutes, a record time of scientific observations not yet beaten and allowing for exceptional measurements. Science, technology, aviation and history combine in the story of a unique human adventure aboard a legendary aircraft, illustrated with a rich and original ...

  19. Sub-shot-noise shadow sensing with quantum correlations.

    Science.gov (United States)

    Toninelli, Ermes; Edgar, Matthew P; Moreau, Paul-Antoine; Gibson, Graham M; Hammond, Giles D; Padgett, Miles J

    2017-09-04

    The quantised nature of the electromagnetic field sets the classical limit to the sensitivity of position measurements. However, techniques based on the properties of quantum states can be exploited to accurately measure the relative displacement of a physical object beyond this classical limit. In this work, we use a simple scheme based on the split-detection of quantum correlations to measure the position of a shadow at the single-photon light level, with a precision that exceeds the shot-noise limit. This result is obtained by analysing the correlated signals of bi-photon pairs, created in parametric downconversion and detected by an electron multiplying CCD (EMCCD) camera employed as a split-detector. By comparing the measured statistics of spatially anticorrelated and uncorrelated photons we were able to observe a significant noise reduction corresponding to an improvement in position sensitivity of up to 17% (0.8dB). Our straightforward approach to sub-shot-noise position measurement is compatible with conventional shadow-sensing techniques based on the split-detection of light-fields, and yields an improvement that scales favourably with the detector's quantum efficiency.

  20. Improving Shadow Suppression for Illumination Robust Face Recognition

    KAUST Repository

    Zhang, Wuming

    2017-10-13

    2D face analysis techniques, such as face landmarking, face recognition and face verification, are reasonably dependent on illumination conditions which are usually uncontrolled and unpredictable in the real world. An illumination robust preprocessing method thus remains a significant challenge in reliable face analysis. In this paper we propose a novel approach for improving lighting normalization through building the underlying reflectance model which characterizes interactions between skin surface, lighting source and camera sensor, and elaborates the formation of face color appearance. Specifically, the proposed illumination processing pipeline enables the generation of Chromaticity Intrinsic Image (CII) in a log chromaticity space which is robust to illumination variations. Moreover, as an advantage over most prevailing methods, a photo-realistic color face image is subsequently reconstructed which eliminates a wide variety of shadows whilst retaining the color information and identity details. Experimental results under different scenarios and using various face databases show the effectiveness of the proposed approach to deal with lighting variations, including both soft and hard shadows, in face recognition.

  1. Performance Analysis of CDMA Wireless Sensor Networks in Shadowed Environment

    Directory of Open Access Journals (Sweden)

    U. DATTA

    2010-07-01

    Full Text Available This paper evaluates the performance of a CDMA based wireless sensor networks (WSN with layered architecture in terms of QoS like outage probability, bit error rate (BER, throughput, and delay, considering correlation amongst interferers in shadowed environment. Energy consumption for successful delivery of information is also evaluated at different channel conditions. Two kinds of interference namely multiple access interference (MAI and node interference (NI are considered and an infinite ARQ is assumed at link layer between a sending node and sink till successful transmission of packetized data. An appropriate analytical model of interference considering correlation amongst interferers, power control error and shadowing is developed for evaluating bit error rate (BER, packet error rate (PER, average number of retransmission for successful delivery of information, throughput, and delay in a single hop communication. A simple energy model is used for evaluating the consumption of energy for successful delivery of information between source and sink. We also evaluate the sink capacity of wireless CDMA sensor networks considering a threshold BER. Sink capacity is defined as the maximum number of sensor nodes transmitting concurrently to the sink and located within one hop layer. The impact of NI on the sink capacity is also indicated. The effects of node density, correlation amongst interferers and power control error (pce on performance of WSN are investigated. Analytical results are supported by simulation results.

  2. Tomographic Particle Image Velocimetry using Smartphones and Colored Shadows.

    Science.gov (United States)

    Aguirre-Pablo, Andres A; Alarfaj, Meshal K; Li, Er Qiang; Hernández-Sánchez, J F; Thoroddsen, Sigurdur T

    2017-06-16

    We demonstrate the viability of using four low-cost smartphone cameras to perform Tomographic PIV. We use colored shadows to imprint two or three different time-steps on the same image. The back-lighting is accomplished with three sets of differently-colored pulsed LEDs. Each set of Red, Green & Blue LEDs is shone on a diffuser screen facing each of the cameras. We thereby record the RGB-colored shadows of opaque suspended particles, rather than the conventionally used scattered light. We subsequently separate the RGB color channels, to represent the separate times, with preprocessing to minimize noise and cross-talk. We use commercially available Tomo-PIV software for the calibration, 3-D particle reconstruction and particle-field correlations, to obtain all three velocity components in a volume. Acceleration estimations can be done thanks to the triple pulse illumination. Our test flow is a vortex ring produced by forcing flow through a circular orifice, using a flexible membrane, which is driven by a pressurized air pulse. Our system is compared to a commercial stereoscopic PIV system for error estimations. We believe this proof of concept experiment will make this technique available for education, industry and scientists for a fraction of the hardware cost needed for traditional Tomo-PIV.

  3. Verbal shadowing and visual interference in spatial memory.

    Science.gov (United States)

    Meilinger, Tobias; Bülthoff, Heinrich H

    2013-01-01

    Spatial memory is thought to be organized along experienced views and allocentric reference axes. Memory access from different perspectives typically yields V-patterns for egocentric encoding (monotonic decline in performance along with the angular deviation from the experienced perspectives) and W-patterns for axes encoding (better performance along parallel and orthogonal perspectives than along oblique perspectives). We showed that learning an object array with a verbal secondary task reduced W-patterns compared with learning without verbal shadowing. This suggests that axes encoding happened in a verbal format; for example, by rows and columns. Alternatively, general cognitive load from the secondary task prevented memorizing relative to a spatial axis. Independent of encoding, pointing with a surrounding room visible yielded stronger W-patterns compared with pointing with no room visible. This suggests that the visible room geometry interfered with the memorized room geometry. With verbal shadowing and without visual interference only V-patterns remained; otherwise, V- and W-patterns were combined. Verbal encoding and visual interference explain when W-patterns can be expected alongside V-patterns and thus can help in resolving different performance patterns in a wide range of experiments.

  4. Tomographic Particle Image Velocimetry using Smartphones and Colored Shadows

    KAUST Repository

    Aguirre-Pablo, Andres A.

    2017-06-12

    We demonstrate the viability of using four low-cost smartphone cameras to perform Tomographic PIV. We use colored shadows to imprint two or three different time-steps on the same image. The back-lighting is accomplished with three sets of differently-colored pulsed LEDs. Each set of Red, Green & Blue LEDs is shone on a diffuser screen facing each of the cameras. We thereby record the RGB-colored shadows of opaque suspended particles, rather than the conventionally used scattered light. We subsequently separate the RGB color channels, to represent the separate times, with preprocessing to minimize noise and cross-talk. We use commercially available Tomo-PIV software for the calibration, 3-D particle reconstruction and particle-field correlations, to obtain all three velocity components in a volume. Acceleration estimations can be done thanks to the triple pulse illumination. Our test flow is a vortex ring produced by forcing flow through a circular orifice, using a flexible membrane, which is driven by a pressurized air pulse. Our system is compared to a commercial stereoscopic PIV system for error estimations. We believe this proof of concept experiment will make this technique available for education, industry and scientists for a fraction of the hardware cost needed for traditional Tomo-PIV.

  5. Tomographic Particle Image Velocimetry Using Colored Shadow Imaging

    KAUST Repository

    Alarfaj, Meshal K.

    2016-02-01

    Tomographic Particle Image Velocimetry Using Colored Shadow Imaging by Meshal K Alarfaj, Master of Science King Abdullah University of Science & Technology, 2015 Tomographic Particle image velocimetry (PIV) is a recent PIV method capable of reconstructing the full 3D velocity field of complex flows, within a 3-D volume. For nearly the last decade, it has become the most powerful tool for study of turbulent velocity fields and promises great advancements in the study of fluid mechanics. Among the early published studies, a good number of researches have suggested enhancements and optimizations of different aspects of this technique to improve the effectiveness. One major aspect, which is the core of the present work, is related to reducing the cost of the Tomographic PIV setup. In this thesis, we attempt to reduce this cost by using an experimental setup exploiting 4 commercial digital still cameras in combination with low-cost Light emitting diodes (LEDs). We use two different colors to distinguish the two light pulses. By using colored shadows with red and green LEDs, we can identify the particle locations within the measurement volume, at the two different times, thereby allowing calculation of the velocities. The present work tests this technique on the flows patterns of a jet ejected from a tube in a water tank. Results from the images processing are presented and challenges discussed.

  6. Astronomy education through hands-on photography workshops

    Science.gov (United States)

    Schofield, I.; Connors, M. G.; Holmberg, R.

    2013-12-01

    Athabasca University (AU), Athabasca University Geophysical and Geo-Space Observatories (AUGO / AUGSO), the Rotary Club of Athabasca and Science Outreach Athabasca has designed a three day science workshop entitled Photography and the Night Sky. This pilot workshop, aimed primarily at high-school aged students, serves as an introduction to observational astronomy as seen in the western Canadian night sky using digital astrophotography without the use of a telescope or tracking mount. Participants learn the layout of the night sky by proficiently photographing it using digital single lens reflex camera (DSLR) kits including telephoto and wide-angle lenses, tripod and cable release. The kits are assembled with entry-level consumer-grade camera gear as to be affordable by the participants, if they so desire to purchase their own equipment after the workshop. Basic digital photo editing is covered using free photo editing software (IrfanView). Students are given an overview of observational astronomy using interactive planetarium software (Stellarium) before heading outdoors to shoot the night sky. Photography is conducted at AU's auroral observatories, both of which possess dark open sky that is ideal for night sky viewing. If space weather conditions are favorable, there are opportunities to photograph the aurora borealis, then compare results with imagery generated by the all-sky auroral imagers located at the Geo-Space observatory. The aim of this program is to develop awareness to the science and beauty of the night sky, while promoting photography as a rewarding, lifelong hobby. Moreover, emphasis is placed on western Canada's unique subauroral location that makes aurora watching highly accessible and rewarding in 2013, the maximum of the current solar cycle.

  7. Smartphone based hemispherical photography for canopy structure measurement

    Science.gov (United States)

    Wan, Xuefen; Cui, Jian; Jiang, Xueqin; Zhang, Jingwen; Yang, Yi; Zheng, Tao

    2018-01-01

    The canopy is the most direct and active interface layer of the interaction between plant and environment, and has important influence on energy exchange, biodiversity, ecosystem matter and climate change. The measurement about canopy structure of plant is an important foundation to analyze the pattern, process and operation mechanism of forest ecosystem. Through the study of canopy structure of plant, solar radiation, ambient wind speed, air temperature and humidity, soil evaporation, soil temperature and other forest environmental climate characteristics can be evaluated. Because of its accuracy and effectiveness, canopy structure measurement based on hemispherical photography has been widely studied. However, the traditional method of canopy structure hemispherical photogrammetry based on SLR camera and fisheye lens. This method is expensive and difficult to be used in some low-cost occasions. In recent years, smartphone technology has been developing rapidly. The smartphone not only has excellent image acquisition ability, but also has the considerable computational processing ability. In addition, the gyroscope and positioning function on the smartphone will also help to measure the structure of the canopy. In this paper, we present a smartphone based hemispherical photography system. The system consists of smart phones, low-cost fisheye lenses and PMMA adapters. We designed an Android based App to obtain the canopy hemisphere images through low-cost fisheye lenses and provide horizontal collimation information. In addition, the App will add the acquisition location tag obtained by GPS and auxiliary positioning method in hemisphere image information after the canopy structure hemisphere image acquisition. The system was tested in the urban forest after it was completed. The test results show that the smartphone based hemispherical photography system can effectively collect the high-resolution canopy structure image of the plant.

  8. Should 'smart phones' be used for patient photography?

    Science.gov (United States)

    Chan, Natalie; Charette, Jacob; Dumestre, Danielle O; Fraulin, Frankie Og

    2016-01-01

    Within the field of plastic surgery, clinical photography is an essential tool. 'Smart phones' are increasingly being used for photography in medical settings. To determine the prevalence of smart phone use for clinical photography among plastic surgeons and plastic surgery residents in Canada. In 2014, a survey was distributed to all members of the Canadian Society of Plastic Surgeons. The questions encompassed four main categories: smart phone use for clinical photos; storage of photos; consent process; and privacy issues. The survey participation rate was 27% (147 of 545) with 103 surgeons and 44 residents. In total, 89.1% (131 of 147) of respondents have taken photographs of patients using smart phones and 57% (74 of 130) store these photos on their phones. In addition, 73% (74 of 102) of respondents store these photos among personal photos. The majority of respondents (75% [106 of 142]) believe obtaining verbal consent before taking clinical photographs is sufficient to ensure privacy is respected. Written consent is not commonly obtained, but 83% (116 of 140) would obtain it, if it could be done more efficiently. Twenty-six percent (31 of 119) of respondents have accidentally shown a clinical photograph on their phone to friends or family. A smart phone application that incorporates a written consent process, and allows photos to be immediately stored externally, is perceived by 59% (83 of 140) to be a possible way to address these issues. Smart phones are commonly used to obtain clinical photographs in plastic surgery. There are issues around consent process, storage of photos and privacy that need to be addressed.

  9. Should ‘smart phones’ be used for patient photography?

    Science.gov (United States)

    Chan, Natalie; Charette, Jacob; Dumestre, Danielle O; Fraulin, Frankie OG

    2016-01-01

    BACKGROUND: Within the field of plastic surgery, clinical photography is an essential tool. ‘Smart phones’ are increasingly being used for photography in medical settings. OBJECTIVE: To determine the prevalence of smart phone use for clinical photography among plastic surgeons and plastic surgery residents in Canada. METHODS: In 2014, a survey was distributed to all members of the Canadian Society of Plastic Surgeons. The questions encompassed four main categories: smart phone use for clinical photos; storage of photos; consent process; and privacy issues. The survey participation rate was 27% (147 of 545) with 103 surgeons and 44 residents. In total, 89.1% (131 of 147) of respondents have taken photographs of patients using smart phones and 57% (74 of 130) store these photos on their phones. In addition, 73% (74 of 102) of respondents store these photos among personal photos. The majority of respondents (75% [106 of 142]) believe obtaining verbal consent before taking clinical photographs is sufficient to ensure privacy is respected. Written consent is not commonly obtained, but 83% (116 of 140) would obtain it, if it could be done more efficiently. Twenty-six percent (31 of 119) of respondents have accidentally shown a clinical photograph on their phone to friends or family. A smart phone application that incorporates a written consent process, and allows photos to be immediately stored externally, is perceived by 59% (83 of 140) to be a possible way to address these issues. CONCLUSION: Smart phones are commonly used to obtain clinical photographs in plastic surgery. There are issues around consent process, storage of photos and privacy that need to be addressed. PMID:27054136

  10. Mapping Chinese tallow with color-infrared photography

    Science.gov (United States)

    Ramsey, Elijah W.; Nelson, G.A.; Sapkota, S.K.; Seeger, E.B.; Martella, K.D.

    2002-01-01

    Airborne color-infrared photography (CIR) (1:12,000 scale) was used to map localized occurrences of the widespread and aggressive Chinese tallow (Sapium sebiferum), an invasive species. Photography was collected during senescence when Chinese tallow's bright red leaves presented a high spectral contrast within the native bottomland hardwood and upland forests and marsh land-cover types. Mapped occurrences were conservative because not all senescing tallow leaves are bright red simultaneously. To simulate low spectral but high spatial resolution satellite/airborne image and digital video data, the CIR photography was transformed into raster images at spatial resolutions approximating 0.5 in and 1.0 m. The image data were then spectrally classified for the occurrence of bright red leaves associated with senescing Chinese tallow. Classification accuracies were greater than 95 percent at both spatial resolutions. There was no significant difference in either forest in the detection of tallow or inclusion of non-tallow trees associated with the two spatial resolutions. In marshes, slightly more tallow occurrences were mapped with the lower spatial resolution, but there were also more misclassifications of native land covers as tallow. Combining all land covers, there was no difference at detecting tallow occurrences (equal omission errors) between the two resolutions, but the higher spatial resolution was associated with less inclusion of non-tallow land covers as tallow (lower commission error). Overall, these results confirm that high spatial (???1 m) but low spectral resolution remote sensing data can be used for mapping Chinese tallow trees in dominant environments found in coastal and adjacent upland landscapes.

  11. Utility of Ward-Based Retinal Photography in Stroke Patients.

    Science.gov (United States)

    Frost, Shaun; Brown, Michael; Stirling, Verity; Vignarajan, Janardhan; Prentice, David; Kanagasingam, Yogesan

    2017-03-01

    Improvements in acute care of stroke patients have decreased mortality, but survivors are still at increased risk of future vascular events and mitigation of this risk requires thorough assessment of the underlying factors leading to the stroke. The brain and eye share a common embryological origin and numerous similarities exist between the small vessels of the retina and brain. Recent population-based studies have demonstrated a close link between retinal vascular changes and stroke, suggesting that retinal photography could have utility in assessing underlying stroke risk factors and prognosis after stroke. Modern imaging equipment can facilitate precise measurement and monitoring of vascular features. However, use of this equipment is a challenge in the stroke ward setting as patients are frequently unable to maintain the required seated position, and pupil dilatation is often not feasible as it could potentially obscure important neurological signs of stroke progression. This small study investigated the utility of a novel handheld, nonmydriatic retinal camera in the stroke ward and explored associations between retinal vascular features and stroke risk factors. This camera circumvented the practical limitations of conducting retinal photography in the stroke ward setting. A positive correlation was found between carotid disease and both mean width of arterioles (r = .40, P = .00571) and venules (r = .30, P = .0381). The results provide further evidence that retinal vascular features are clinically informative about underlying stroke risk factors and demonstrate the utility of handheld retinal photography in the stroke ward. Copyright © 2017 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  12. Discursive Shadowing in Linguistic Ethnography. Situated Practices and Circulating Discourses in Multilingual Schools

    Science.gov (United States)

    Dewilde, Joke; Creese, Angela

    2016-01-01

    We consider discursive shadowing as methodology in linguistic ethnography and how it refines our analyses of participants' situated practices. In addition to the constant and extended company the researcher and key participant keep with one another in the field, shadowing in a linguistic ethnographic approach includes the ubiquitous…

  13. Accurate moving cast shadow suppression based on local color constancy detection.

    Science.gov (United States)

    Amato, Ariel; Mozerov, Mikhail G; Bagdanov, Andrew D; Gonzàlez, Jordi

    2011-10-01

    This paper describes a novel framework for detection and suppression of properly shadowed regions for most possible scenarios occurring in real video sequences. Our approach requires no prior knowledge about the scene, nor is it restricted to specific scene structures. Furthermore, the technique can detect both achromatic and chromatic shadows even in the presence of camouflage that occurs when foreground regions are very similar in color to shadowed regions. The method exploits local color constancy properties due to reflectance suppression over shadowed regions. To detect shadowed regions in a scene, the values of the background image are divided by values of the current frame in the RGB color space. We show how this luminance ratio can be used to identify segments with low gradient constancy, which in turn distinguish shadows from foreground. Experimental results on a collection of publicly available datasets illustrate the superior performance of our method compared with the most sophisticated, state-of-the-art shadow detection algorithms. These results show that our approach is robust and accurate over a broad range of shadow types and challenging video conditions. © 2011 IEEE

  14. Shadow enhancement in synthetic aperture sonar imagery for improved target classification

    NARCIS (Netherlands)

    Sabel, J.C.; Groen, J.; Quesson, B.A.J.

    2005-01-01

    The acoustic shadow of a target is a strong classification clue in naval mine hunting. A shadow of bottom targets appears at relatively short ranges (≤ about 200 m) in high resolution images from sidescan or synthetic aperture sonar (SAS), against a background of sea floor reverberation. In SAS

  15. Work-Shadowing as a Process for Facilitating Leadership Succession in Primary Schools

    Science.gov (United States)

    Simkins, Tim; Close, Paul; Smith, Robin

    2009-01-01

    Work-shadowing is an under-researched aspect of leadership development. This paper places workshadowing in the broader context of responses to the challenges of managing leadership succession in schools, drawing on an evaluation of a pilot shadowing programme for aspiring primary headteachers. The paper identifies a number of key themes in…

  16. Qualitative Shadowing as a Research Methodology for Exploring Early Childhood Leadership in Practice

    Science.gov (United States)

    Bøe, Marit; Hognestad, Karin; Waniganayake, Manjula

    2017-01-01

    This article explores qualitative shadowing as an interpretivist methodology, and explains how two researchers participating simultaneously in data collection using a video recorder, contextual interviews and video-stimulated recall interviews, conducted a qualitative shadowing study at six early childhood centres in Norway. This paper emerged…

  17. Implementing content constraints in alpha-stratified adaptive using a shadow test approach

    NARCIS (Netherlands)

    van der Linden, Willem J.; Chang, Hua-Hua

    2003-01-01

    The methods of alpha-stratified adaptive testing and constrained adaptive testing with shadow tests are combined. The advantages are twofold: First, application of the shadow test approach allows the implementation of any type of constraint on item selection in alpha-stratified adaptive testing.

  18. Implementing content constraints in alpha-stratified adaptive testing using a shadow test approach

    NARCIS (Netherlands)

    van der Linden, Willem J.; Chang, Hua-Hua

    2001-01-01

    The methods of alpha-stratified adaptive testing and constrained adaptive testing with shadow tests are combined in this study. The advantages are twofold. First, application of the shadow test allows the researcher to implement any type of constraint on item selection in alpha-stratified adaptive

  19. The Job Shadow Assignment: Career Perceptions in Hospitality, Recreation and Tourism

    Science.gov (United States)

    Padron, Thomas C.; Fortune, Mary F.; Spielman, Melany; Tjoei, Sylvie

    2017-01-01

    The job shadow study measured student career perceptions related to hospitality, recreation and tourism (HRT) and instructional mode (face-to-face (F2F), hybrid, and online). College students self-selecting into three different course modalities taught by the same instructor job shadowed HRT professionals by using Internet and F2F interviews. The…

  20. Interplay of Internal and External Representations: Students' Drawings and Textual Explanations about Shadow Phenomena

    Science.gov (United States)

    Valanides, Nicos; Efthymiou, Irene; Angeli, Charoula

    2013-01-01

    Fifty-six third-year kindergarten student teachers (KTS) were presented with an experimental setting for investigating shadow phenomena. Prior to performing any specific experiment, KTS were asked to externalize their ideas about shadow phenomena corresponding to different configurations of the experimental setting through the use of drawings…

  1. The Link between Speech Perception and Production Is Phonological and Abstract: Evidence from the Shadowing Task

    Science.gov (United States)

    Mitterer, Holger; Ernestus, Mirjam

    2008-01-01

    This study reports a shadowing experiment, in which one has to repeat a speech stimulus as fast as possible. We tested claims about a direct link between perception and production based on speech gestures, and obtained two types of counterevidence. First, shadowing is not slowed down by a gestural mismatch between stimulus and response. Second,…

  2. Shadow Education in Spain: Examining Social Inequalities through the Analysis of PISA Results

    Science.gov (United States)

    Runte-Geidel, Ariadne; Marzo, Pedro Femia

    2015-01-01

    This article examines the use of shadow education by students of compulsory secondary education in Spain over the period 2000-2010. The study identifies the proportion of the student population that uses this type of education and examines how the use of shadow education has evolved during this period. Data was drawn from the student questionnaire…

  3. Kite aerial photography (KAP) as a tool for field teaching

    DEFF Research Database (Denmark)

    Sander, Lasse

    2014-01-01

    Kite aerial photography (KAP) is proposed as a creative tool for geography field teaching and as a medium to approach the complexity of readily available geodata. The method can be integrated as field experiment, surveying technique or group activity. The acquired aerial images can instantaneously...... be integrated in geographic information systems and used for reflection and discussion. The use of KAP in field teaching aims at conveying spatial perception and observational skills in real environments to later enable students to interpret remotely sensed data from a nadir perspective. KAP thus allows adding...

  4. [Documentation of orthodontic clinical cases. Photography in orthodontics. 2].

    Science.gov (United States)

    Ronchin, M; Dessì, S; Oddini, S

    1989-01-01

    We have analysed the bases of information about the feasibility of orthodontic photography. After giving details about the photographic equipment and the field lighting we gave a thorough description of the operative modalities of intra and extraoral photos. We have given special emphasis to the framing phase which is of great importance for successful photograms. This is important both for projection and setting together of case display. Eventually the most frequent mistakes are pointed out. A useful dialogue for daily clinical practice is given hereby.

  5. Pathology Gross Photography: The Beginning of Digital Pathology.

    Science.gov (United States)

    Rampy, B Alan; Glassy, Eric F

    2015-06-01

    The underutilized practice of photographing anatomic pathology specimens from surgical pathology and autopsies is an invaluable benefit to patients, clinicians, pathologists, and students. Photographic documentation of clinical specimens is essential for the effective practice of pathology. When considering what specimens to photograph, all grossly evident pathology, absent yet expected pathologic features, and gross-only specimens should be thoroughly documented. Specimen preparation prior to photography includes proper lighting and background, wiping surfaces of blood, removing material such as tubes or bandages, orienting the specimen in a logical fashion, framing the specimen to fill the screen, positioning of probes, and using the right-sized scale. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Declassified Intelligence Satellite Photography (DISP) Coverage of Antarctica

    Science.gov (United States)

    Bindschadler, Robert; Seider, Wendy

    1998-01-01

    This report summarizes the results of a nine-week summer project examining all Declassified Intelligence Satellite Photography (DISP) of Antarctica. It was discovered that the data were collected in three separate missions during 1962 and 1963. The first two missions covered only the coastal areas, while the third mission covered the entire continent. Many of the 1782 frames collected were cloudy. This is especially true of West Antarctica. An optimal set of photographs covering the entire Antarctic coastline is identified along with some examples that show changes in the coastline which have occurred since the early 1960s.

  7. Aerial Photography and Imagery, Ortho-Corrected, 4 inch aerial photography (color, infrared, and color oblique) in urban areas, 1 foot in national forest, Published in 2006, 1:600 (1in=50ft) scale, Los Angeles County Government.

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — Aerial Photography and Imagery, Ortho-Corrected dataset current as of 2006. 4 inch aerial photography (color, infrared, and color oblique) in urban areas, 1 foot in...

  8. Digital photography for assessing the link between vegetation phenology and CO2 exchange in two contrasting northern ecosystems

    Science.gov (United States)

    Linkosalmi, Maiju; Aurela, Mika; Tuovinen, Juha-Pekka; Peltoniemi, Mikko; Tanis, Cemal M.; Arslan, Ali N.; Kolari, Pasi; Böttcher, Kristin; Aalto, Tuula; Rainne, Juuso; Hatakka, Juha; Laurila, Tuomas

    2016-09-01

    Digital repeat photography has become a widely used tool for assessing the annual course of vegetation phenology of different ecosystems. By using the green chromatic coordinate (GCC) as a greenness measure, we examined the feasibility of digital repeat photography for assessing the vegetation phenology in two contrasting high-latitude ecosystems. Ecosystem-atmosphere CO2 fluxes and various meteorological variables were continuously measured at both sites. While the seasonal changes in GCC were more obvious for the ecosystem that is dominated by annual plants (open wetland), clear seasonal patterns were also observed for the evergreen ecosystem (coniferous forest). Daily and seasonal time periods with sufficient solar radiation were determined based on images of a grey reference plate. The variability in cloudiness had only a minor effect on GCC, and GCC did not depend on the sun angle and direction either. The daily GCC of wetland correlated well with the daily photosynthetic capacity estimated from the CO2 flux measurements. At the forest site, the correlation was high in 2015 but there were discernible deviations during the course of the summer of 2014. The year-to-year differences were most likely generated by meteorological conditions, with higher temperatures coinciding with higher GCCs. In addition to depicting the seasonal course of ecosystem functioning, GCC was shown to respond to environmental changes on a timescale of days. Overall, monitoring of phenological variations with digital images provides a powerful tool for linking gross primary production and phenology.

  9. a Novel Method of Cloud and Shadow Extraction with Multi-Temporal LANDSAT8 Oli Images

    Science.gov (United States)

    Ni, Y.; He, G.; Jiang, W.

    2017-09-01

    Cloud and Shadow removal is a significant step in remote sensing image process. As we all know, the ground object coverage type of the same area of the remote sensing image has little change in the short term. But for cloud and shadow coverage areas, the ground object coverage type has large change. Therefore, according to the difference between the two Landsat / OLI images caused by changes in the cover, this paper presents a method of extracting clouds and shadows based on differences in luminance values. This method selects two thresholds for the difference of brightness values, and extracts the clouds and shadows respectively, and validates them with random point method, which can obtain high precision of extracting cloud and shadow and satisfy the actual application needs.

  10. Shadow Probability of Detection and False Alarm for Median-Filtered SAR Imagery

    Energy Technology Data Exchange (ETDEWEB)

    Raynal, Ann Marie [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). ISR Analysis and Applications Dept.; Doerry, Armin Walter [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). ISR Mission Engineering Dept.; Miller, John A. [General Atomics Aeronautical Systems, Inc., San Diego, CA (United States). Mission Systems; Bishop, Edward E. [General Atomics Aeronautical Systems, Inc., San Diego, CA (United States). Mission Systems; Horndt, Volker [General Atomics Aeronautical Systems, Inc., San Diego, CA (United States). Mission Systems

    2014-06-01

    Median filtering reduces speckle in synthetic aperture radar (SAR) imagery while preserving edges, at the expense of coarsening the resolution, by replacing the center pixel of a sliding window by the median value. For shadow detection, this approach helps distinguish shadows from clutter more easily, while preserving shadow shape delineations. However, the nonlinear operation alters the shadow and clutter distributions and statistics, which must be taken into consideration when computing probability of detection and false alarm metrics. Depending on system parameters, median filtering can improve probability of detection and false alarm by orders of magnitude. Herein, we examine shadow probability of detection and false alarm in a homogeneous, ideal clutter background after median filter post-processing. Some comments on multi-look processing effects with and without median filtering are also made.

  11. Spacecraft’s attitude prediction: solar radiation torque and the Earth’s shadow

    Science.gov (United States)

    Zanardi, M. C.; Vilhena de Moraes, R.; Cabette, R. E. S.; Garcia, R. V.

    A semi-analytical approach is proposed to study the rotational motion of an artificial satellite, under the influence of torque due to the solar radiation pressure, and taking into account the influence of Earth's shadow. Using Andoyer variables the equations for the rotational motion are presented in extended Hamiltonian form. In order to get a solution for the state variables close to an actual motion, the considered model for the shadow function takes into account physical and geometric factors and three specific regions: shadow, penumbra and full light. A mapping for the shadow function is proposed and a semi-analytical process is applied. When the satellite is totally illuminated or it is inside the penumbra, a known analytical solution is used to compute the satellite's attitude. A numerical simulation shows, when the penumbra region is included, the attenuation of the rotational motion during the transition from the shadow to the illuminate region and vice versa.

  12. Detection of retinal lesions in diabetic retinopathy: comparative evaluation of 7-field digital color photography versus red-free photography.

    Science.gov (United States)

    Venkatesh, Pradeep; Sharma, Reetika; Vashist, Nagender; Vohra, Rajpal; Garg, Satpal

    2015-10-01

    Red-free light allows better detection of vascular lesions as this wavelength is absorbed by hemoglobin; however, the current gold standard for the detection and grading of diabetic retinopathy remains 7-field color fundus photography. The goal of this study was to compare the ability of 7-field fundus photography using red-free light to detect retinopathy lesions with corresponding images captured using standard 7-field color photography. Non-stereoscopic standard 7-field 30° digital color fundus photography and 7-field 30° digital red-free fundus photography were performed in 200 eyes of 103 patients with various grades of diabetic retinopathy ranging from mild to moderate non-proliferative diabetic retinopathy to proliferative diabetic retinopathy. The color images (n = 1,400) were studied with corresponding red-free images (n = 1,400) by one retina consultant (PV) and two senior residents training in retina. The various retinal lesions [microaneurysms, hemorrhages, hard exudates, soft exudates, intra-retinal microvascular anomalies (IRMA), neovascularization of the retina elsewhere (NVE), and neovascularization of the disc (NVD)] detected by all three observers in each of the photographs were noted followed by determination of agreement scores using κ values (range 0-1). Kappa coefficient was categorized as poor (≤0), slight (0.01-0.20), fair (0.2 -0.40), moderate (0.41-0.60), substantial (0.61-0.80), and almost perfect (0.81-1). The number of lesions detected by red-free images alone was higher for all observers and all abnormalities except hard exudates. Detection of IRMA was especially higher for all observers with red-free images. Between image pairs, there was substantial agreement for detection of hard exudates (average κ = 0.62, range 0.60-0.65) and moderate agreement for detection of hemorrhages (average κ = 0.52, range 0.45-0.58), soft exudates (average κ = 0.51, range 0.42-0.61), NVE (average κ = 0.47, range 0.39-0.53), and NVD

  13. Comparison of satellite imagery and infrared aerial photography as vegetation mapping methods in an arctic study area: Jameson Land, East Greenland

    DEFF Research Database (Denmark)

    Hansen, Birger Ulf; Mosbech, Anders

    1994-01-01

    Remote Sensing, vegetation mapping, SPOT, Landsat TM, aerial photography, Jameson Land, East Greenland......Remote Sensing, vegetation mapping, SPOT, Landsat TM, aerial photography, Jameson Land, East Greenland...

  14. TV shearography: quantitative measurement of shear-magnitude fields by use of digital speckle photography.

    Science.gov (United States)

    Andersson, A; Krishna Mohan, N; Sjödahl, M; Molin, N E

    2000-06-01

    Digital speckle photography combined with TV shearography is developed for precise measurement of the magnitude of the shear field in a linear shear configuration. As an application the method is implemented to determine the slope-change variations of a three-dimensional object with TV shearography in which the shear magnitude is obtained with the digital speckle photography technique.

  15. Through the lens of young people: use of photography in hospital design.

    Science.gov (United States)

    Coad, Jane

    2016-05-09

    Whilst arts in hospitals have been perceived as therapeutic to patients, this paper will share evidence and research to support that photography and photo-elicitation has an important role in preference and choice about hospital design. The paper will initially draw on studies that used participatory photography in children's hospital design in international settings.

  16. Using Photography To Enhance Language and Learning: A Picture Can Encourage a Thousand Words.

    Science.gov (United States)

    Tarulli, Nancy J.

    1998-01-01

    Discusses how speech-language pathologists can use photography to encourage more active language expression in children with language and learning disabilities, and describes seven categories for photography use in language learning environments. Each photo project includes suggested language objectives, applications, and advantages. (Author/CR)

  17. The use of high altitude aerial photography to inventory wildlife habitat in Kansas: An initial evaluation

    Science.gov (United States)

    Merchant, J. W.; Waddell, B. H.

    1974-01-01

    The use of aerial photography as a method for determining the wildlife conditions of an area is discussed. Color infrared photography is investigated as the most effective type of remote sensor. The characteristics of the remote sensing systems are described. Examples of the remote sensing operation and the method for reducing the data are presented.

  18. Understanding Photography as Applied Chemistry: Using Talbot's Calotype Process to Introduce Chemistry to Design Students

    Science.gov (United States)

    Ro¨sch, Esther S.; Helmerdig, Silke

    2017-01-01

    Early photography processes were predestined to combine chemistry and art. William Henry Fox Talbot is one of the early photography pioneers. In 2-3 day workshops, design students without a major background in chemistry are able to define a reproducible protocol for Talbot's gallic acid containing calotype process. With the experimental concept…

  19. Photography Basics. Capturing the Essence of Physical Education and Sport Programs.

    Science.gov (United States)

    Kluka, Darlene A.; Mitchell, Carolyn B.

    1990-01-01

    The physical educator or coach may be responsible for marketing programs to the public, and skill in 35mm photography can help. Ingredients necessary for successful 35mm movement photography are discussed: knowledge of the movement and the appropriate equipment; techniques for capturing movement; positioning for the ultimate shot; and practice.…

  20. Using Photography and Art in Concept Mapping Research with Adults with Dyslexia

    Science.gov (United States)

    Williams Carawan, Lena; Nalavany, Blace

    2010-01-01

    Reflexive photography for individual interviews and the use of art with focus groups provides a valuable method for exploring the psychosocial issues encountered by adults with dyslexia. Reflexive photography and art is particularly appropriate when interviewing adults with dyslexia who may have difficulty expressing and focusing on what they want…

  1. Counseling through Images: Using Photography to Guide the Counseling Process and Achieve Treatment Goals

    Science.gov (United States)

    Ginicola, Misty M.; Smith, Cheri; Trzaska, Jessica

    2012-01-01

    Creative approaches to counseling help counselors to meet the needs of diverse populations. The utility of photography in counseling has been demonstrated through several case studies; however, clear implications of how photography relates to the counseling process have not been well delineated. The existing literature on phototherapy is reviewed…

  2. The Power of Photography as a Catalyst for Teaching Informational Writing

    Science.gov (United States)

    Lilly, Elizabeth; Fields, Charla

    2014-01-01

    Writing and photography are composition processes that help develop children's linguistic and visual competencies, respectively. Using photography in teaching writing has been found to enhance students' literacy skills by naturally invoking their interest and motivation, and eventually strengthening the reading-writing relationship. Children can…

  3. 78 FR 40544 - Culturally Significant Objects Imported for Exhibition Determinations: “New Photography 2013...

    Science.gov (United States)

    2013-07-05

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF STATE Culturally Significant Objects Imported for Exhibition Determinations: ``New Photography 2013: Adam Broomberg..., 2003), I hereby determine that the objects to be included in the exhibition ``New Photography 2013...

  4. Setting apart the amateur from the professional: maintaining the value of standardised representational photography.

    Science.gov (United States)

    Banks, Debbie

    2014-10-01

    The purpose of this paper is to discuss the importance of standard representational photography in clinical photography and its aid in maintaining the gold standard in the medical illustration profession. it is important that professionals are aware of potential threats to good practice with many areas identified in the article.

  5. The Evolution of Photography and Three-Dimensional Imaging in Plastic Surgery.

    Science.gov (United States)

    Weissler, Jason M; Stern, Carrie S; Schreiber, Jillian E; Amirlak, Bardia; Tepper, Oren M

    2017-03-01

    Throughout history, the technological advancements of conventional clinical photography in plastic surgery have not only refined the methods available to the plastic surgeon, but have invigorated the profession through technology. The technology of the once traditional two-dimensional photograph has since been revolutionized and refashioned to incorporate novel applications, which have since become the standard in clinical photography. Contrary to traditional standardized two-dimensional photographs, three-dimensional photography provides the surgeon with an invaluable volumetric and morphologic analysis by demonstrating true surface dimensions both preoperatively and postoperatively. Clinical photography has served as one of the fundamental objective means by which plastic surgeons review outcomes; however, the newer three-dimensional technology has been primarily used to enhance the preoperative consultation with surgical simulations. The authors intend to familiarize readers with the notion that three-dimensional photography extends well beyond its marketing application during surgical consultation. For the cosmetic surgeon, as the application of three-dimensional photography continues to mature in facial plastic surgery, it will continue to bypass the dated conventional photographic methods plastic surgeons once relied on. This article reviews a paradigm shift and provides a historical review of the fascinating evolution of photography in plastic surgery by highlighting the clinical utility of three-dimensional photography as an adjunct to plastic and reconstructive surgery practices. As three-dimensional photographic technology continues to evolve, its application in facial plastic surgery will provide an opportunity for a new objective standard in plastic surgery.

  6. The Importance of Artificial Light in the Development of Night Photography.

    Science.gov (United States)

    Wood, Deloris

    This study traces the development of night photography, from February 7, 1839, when the effect of the moon on a Daguerreotype was first recorded by Alexander Von Humboldt, to the present. The contributions of the following photographers who advanced the field of night photography are discussed: Margaret Bourke-White, Paul Martin, Brassai, Bill…

  7. Light tries the expert eye : The introduction of photography in nineteenth-century macroscopic neuroanatomy

    NARCIS (Netherlands)

    de Rijcke, Sarah

    2008-01-01

    It is often argued that photography's scientific inauguration meaningfully coincided with a shift towards the ideal of mechanical objectivity. Values of disinterestedness and precision were readily attributed to photography and were cherished by the emerging field of neurology as well. However,

  8. Contemporary Art Photography In The Context Of Urban Symbols

    Directory of Open Access Journals (Sweden)

    Tuna Uysal

    2016-12-01

    Full Text Available The symbols that landscape art contains, shows us cultural and intellectual evolution of the humankind. The “Bourgeoisie”, as the initiator of the “Urbanization” also supports the thoughts, which made this evolution possible. This impulse shows itself in two different ways; first, the frame of mind, which made visual codes possible to come into reality. Second, developing the medium, which made this visual codes record possible. It is possible to see the developing of the thought urbanization in every example of fine arts, in every age. Today, the art of photography uses landscape as background of its main theme as well as its major story, by the means of contemporary studies. These practices constitute the background of the main theme, both intellectual and visual way. Most accurate way to record today’s world, both intellectual and visual way -as can be seen in the history of photography- is to associate the story and its background, by the means of cultural and artistic studies. Whereby, the artist invites viewer into the narrative by this way and increases the chance to give message in a more striking manner. Existence of the urban symbols in the artwork is vital because it makes possible to learn more about the place, subject, society and period of the story and eventually about the main theme.

  9. Chapter 20: neurological illustration from photography to cinematography.

    Science.gov (United States)

    Aubert, Geneviève

    2010-01-01

    This chapter explores iconography in neurology from the birth of photography up to the early medical applications of cinematography before 1914. The important visual part of neurological diagnosis explains why these techniques were adopted very early by neurologists. Duchenne published the first medical book illustrated with photographs of patients. The first and most famous photographic laboratory was created in Charcot's department, at the Salpêtrière in Paris, under the direction of Albert Londe. Londe published the first book dedicated to medical photography. The physiologist Marey and the photographer Muybridge, in association with neurologists, played key roles in the development of chronophotography and cinematography. Germany was the first country to welcome cinematography in a neurology department. Independently, neurologists began to film patients in other countries in Europe and in America. In 1905, Arthur Van Gehuchten (1861-1914), Belgian anatomist and neurologist, began systematically to film neurologic patients, with the intention of building up a complete neurological iconographic collection. This collection has survived and has been restored in the laboratory of the Royal Belgian Film Archive where the films are now safely stored in their vaults.

  10. Skin lesion metrics: role of photography in acne.

    Science.gov (United States)

    Chiang, Audris; Hafeez, Farhaan; Maibach, Howard I

    2014-04-01

    Accurate assessment of acne severity is essential for determining the appropriate treatment required. This paper reviews photographic methods for such assessment. Literature included met the following criteria: proposed photographic standards to assess acne, evaluated such standards, or offered photographic methods to improve visualization and assessment. Validity was evaluated by comparing given photographic grading methods to other methods, such as lesion counting. Many photographic standards were shown to be objective, time-efficient, and have intra-grader and inter-grader consistency. Photography also documents progress for retrospective verification. Drawbacks include not allowing determination of depth, minimization of small lesions and erythema, and difficulty in maintaining consistent settings. Fluorescence and polarized photography improve visualization beyond clinical observation alone. Advances such as computer alignment, imaging segmentation, and three-dimensional analysis methods track lesions and measure objective characteristics. The combined experience summarized here strongly promotes the use of a photographic standard in assessing acne severity. Cook's method can also be used to train and qualify graders. Photographic advancements improve accuracy of assessment by solving problems with consistent settings and depth visualization. Further advancements can improve image analysis through analysis of objective attributes.

  11. “Transformative looks”: Practicing Citizenship Through Photography

    Directory of Open Access Journals (Sweden)

    Sónia Pereira

    2016-12-01

    Full Text Available Purpose: The article discusses the meanings of citizenship and citizenship education when formal citizenship is restricted by exploring the potential of photography education and practice as a tool that promotes the exercise of citizenship in the context of non-formal critical adult education. By doing it, this text aims to enhance our understanding on the ways art education can improve the achievement of the goals of citizenship education. Method: This article analyses the experience of the collective and collaborative project: “Con la cámara a cuestas: Transformative Looks”, in Bilbao, Spain, with a group of fifteen to twenty migrant women from eight Latin American countries. Findings: Citizenship as a life-long learning process involving individual as well as collective action leading to the promotion of new shared values for more inclusive communities benefits greatly from the use of artistic expressions such as photography. Because of migrant women’s marginalized position as non-formal-citizens, citizenship as participation effectively becomes a fundamental route of influence in the public sphere. Conceptualizing citizenship as struggle and as a critical learning process opens up possibilities for generating new shared ‘habitus’, where ‘recognition’ can be achieved leading to more inclusive societies.

  12. Quantitative Image Analysis Techniques with High-Speed Schlieren Photography

    Science.gov (United States)

    Pollard, Victoria J.; Herron, Andrew J.

    2017-01-01

    Optical flow visualization techniques such as schlieren and shadowgraph photography are essential to understanding fluid flow when interpreting acquired wind tunnel test data. Output of the standard implementations of these visualization techniques in test facilities are often limited only to qualitative interpretation of the resulting images. Although various quantitative optical techniques have been developed, these techniques often require special equipment or are focused on obtaining very precise and accurate data about the visualized flow. These systems are not practical in small, production wind tunnel test facilities. However, high-speed photography capability has become a common upgrade to many test facilities in order to better capture images of unsteady flow phenomena such as oscillating shocks and flow separation. This paper describes novel techniques utilized by the authors to analyze captured high-speed schlieren and shadowgraph imagery from wind tunnel testing for quantification of observed unsteady flow frequency content. Such techniques have applications in parametric geometry studies and in small facilities where more specialized equipment may not be available.

  13. Psychology and photography: chimneys dreaming and chimneys warriors

    Directory of Open Access Journals (Sweden)

    Tilde Giani Gallino

    2013-02-01

    Full Text Available The article covers two aspects related to Psychology and Art. The first aspect concerns the similarities found between photography and various Schools of experimental psychology. For instance, the scientists of Psychology of ethological theory, and Non-verbal communication (NVC, observe with particular methodologies the non-verbal messages that animals and humans transmit to their peers through expressions, posture, gestures. The same is done by photographers (those who use the “camera” with a good knowledge of the medium and a “photographic  eye” when they look around, careful to catch an expression, any unusual attitude, or a gesture of friendship. Another School of psychology, the Gestalpsychologie (Gestalt: form, figure, configuration, attributes a decisive value to the perception of space, the foreground and the background, the perspective and vanishing points, the contrast between black and white. All aspects that effectively interest psychologists just as much as photographers. Finally, the second aspect relates to the art of Antony Gaudì and makes some hypothesis about the personality and behavior of the great architect, with regard to the construction of two houses, "Casa Batllo" and "Casa Mila": particularly because of the configuration or Gestalt of the "chimneys" that dominate the two buildings. In this study, cooperate each other psychological analysis and the art of photography. The last enables us to study also the details of the work of Gaudì, as can be seen in the pictures of this essay.

  14. Urban Image. Photography and Images Interactive Semi-immersive

    Directory of Open Access Journals (Sweden)

    Mauro Chiarella

    2009-12-01

    Full Text Available The traditional relation among photographs and drawing relates the study, the representation and the proyectualidad of settings and landscapes of cities, with a history of the urban image and its methods of elaboration. Since the lineal perspectives and the camera obscura of the vedutistas Italian of the 18th century; passing for the cylindrical panorama of the 19th century; the photographic collage of the vanguards of the 20th century and the contemporary resources of the digital photography, a continuity of the urban graphic speech is built oscillating: of the totality to the fragment, of the lineal conical perspective to the digital collage and of the images two-dimensional to the interactive and semi-immersive 3D image. With the potentiality that suggests the use of the digital photography for the relevamiento, study and proyectación of urban fragments an application developed is described partly in a Workshop International of the Universita di Bologna and a proposal of didactic methodology based on the reconstruction vectorial three-dimensional from spherical panorama 360º.

  15. Capturing the worlds of multiple sclerosis: Hannah Laycock's photography.

    Science.gov (United States)

    Bolaki, Stella

    2017-03-01

    This essay explores UK photographer Hannah Laycock's Awakenings and, to a lesser extent, Perceiving Identity that were created in 2015, following her diagnosis with multiple sclerosis (MS) in 2013. It draws on scholarship by people with chronic illness while situating these two MS projects in the context of Laycock's earlier art and portrait photography dealing with fragility, image and desire, and power relations between subject and observer. The analysis illustrates how her evocative photography captures the lived or subjective experience of an invisible and often misunderstood condition by initially focusing on the tension between transparency and opacity in her work. It further shows how her images counter dominant didactic metaphors such as, 'the body as machine', that perpetuate the dehumanising and objectifying aspects of medical care. Subsequent sections trace the influence that Oliver Sacks has had on Laycock's practice, and reflect on other metaphors and tropes in Awakenings that illuminate the relationship between body and self in MS. The essay concludes by acknowledging the therapeutic power of art and calling upon health professionals to make more use of such artistic work in clinical practice. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  16. The effects of fundus photography on the multifocal electroretinogram.

    Science.gov (United States)

    Suresh, Sandip; Tienor, Brian J; Smith, Scott D; Lee, Michael S

    2016-02-01

    To determine the effect of flash fundus photography (FFP) on the multifocal electroretinogram (mfERG). Ten subjects underwent mfERG testing on three separate dates. Subjects received either mfERG without FFP, mfERG at 5 and 15 min after FFP, or mfERG at 30 and 45 min after FFP on each date. The FFP groups received 10 fundus photographs followed by mfERG testing, first of the right eye then of the left eye 10 min later. Data were averaged and analyzed in six concentric rings at each time point. Average amplitude and implicit times of the N1, P1, and N2 peaks for each concentric ring at each time point after FFP were compared to baseline. Flash fundus photography did not lead to a significant change of amplitude or implicit times of N1, P1, or N2 at 5 min after light exposure. These findings suggest that it is acceptable to perform mfERG testing without delay after performance of FFP.

  17. PHOTOGRAPHY AS A MEANS OF DEPICTING GENIUS LOCI?

    Directory of Open Access Journals (Sweden)

    Iulia DOROFTEI

    2016-10-01

    Full Text Available The paper aims to explore the concept of genius loci (spirit of a place starting from Christian Norberg-Schulz’s notable work “Genius Loci: Towards a Phenomenology of Architecture” and to reflect on the possibility of capturing the spirit of a place through photography. The problem arises in the context of a predominantly visual culture, where photography has become an accesible and omnipresent means of experiencing the world and, therefore, considered a convenient tool for gaining (a type of knowledge. A photographic method of exploring the spirirt of the place could serve in understanding local characteristics, in identifying the elements that make a place unique and recognizible. Norberg-Schulz’s position and other views on the concept of genius loci have been analysed. A photo-essay was employed in order to explore the spirit of the old town of Chefchaouen in Morocco and the ambiguity and dual nature of the concept. A critical reflection was conducted with respect to the results.

  18. Veiling the Mechanical Eye: Antoine Claudet and the Spectacle of Photography in Victorian London

    Directory of Open Access Journals (Sweden)

    Stephen Monteiro

    2008-10-01

    Full Text Available The rise of commercial portrait photography in the mid-nineteenth century placed the bourgeois body squarely within technological processes of visual representation. Photography's chemical and optical operations required the subject's physical presence before the camera's mechanical eye, reciprocally exposing the apparatus to the subject's fixed gaze and provoking an unprecedented confrontation of vision, body and technology. Setting the client within photography's technical processes, however, could endanger efforts to promote photographic portraiture as a product of artistic endeavour. In response to this in photography's first decade, London studio owner Antoine Claudet enshrouded the apparatus in a competing visual rhetoric evoking luxury and the sublime. Examining contemporary accounts of Claudet's studios and neighbouring attractions of entertainment and consumption uncovers the overlapping references to enlightenment, beauty and pleasure that surrounded photography's early machinery. While this alternative discourse may have softened the stare of the mechanical eye, it nevertheless contributed to technology's increasing hold on the body and mind.

  19. Analysis of Snow Line and Albedo Conditions By Means of Time-Lapse Photography on Tapado Glacier, Chile

    Science.gov (United States)

    Vivero, S.; MacDonell, S.; McPhee, J. P.

    2014-12-01

    In the semiarid Coquimbo Region of Chile, high-altitude glaciers and seasonal snow are important sources of freshwater for irrigated agriculture and urban consumption. Due to the aridity of the environment, losses due to sublimation are large which means that accurate melt modelling is essential in order to reliably estimate streamflow. Since 2008, the CEAZA glaciology group has been studying the energy and mass balance of the largest glacier in the catchment, the Tapado Glacier using field and remote sensing measurements, and numerical modelling. The Tapado glacier system (30°08' S, 69°55' W) is a complex assemblage of uncovered and debris-covered ice located at the head of the Elqui basin between 4500 and 5536 m a.s.l. Energy balance modelling studies at the site have been limited in scope due to the development of ice pinnacles or penitentes on snow and ice surfaces. These features complicate energy distribution across the surface, due to modifications of parameters such as albedo. In this paper, we use time-lapse photography and automatic weather station (AWS) measurements to investigate how the development of penitentes impacts the spatial and temporal variability of albedo across the glacier surface and whether terrestrial photography is appropriate for use at such locations. Oblique photographs obtained from a high vantage point were georeferenced using a high resolution digital elevation model available for the entire glacier and its environs. By comparing the photographic data with point albedo measurements made at an AWS, distributed albedo maps were produced. Preliminary results suggest that distributed albedo values may be underestimated by the formation and development of penitentes during the ablation season. Moreover, it was observed that the evolution of the snow line during summer was not only topographically controlled but also modified by occasional convective snowfalls. Time-lapse photography provided to be a cost-effective tool for monitoring

  20. Aerial Photography and Imagery, Ortho-Corrected, Polk County retained Ayres Associates to acquire digital aerial photography during the spring of 2010 suitable for the production of color orthophotography at a 12-inch ground pixel resolution (approximately 956 sq. miles). The photography was obtained du, Published in 2010, 1:2400 (1in=200ft) scale, Polk County Government.

    Data.gov (United States)

    NSGIC Local Govt | GIS Inventory — Aerial Photography and Imagery, Ortho-Corrected dataset current as of 2010. Polk County retained Ayres Associates to acquire digital aerial photography during the...

  1. Coupling GB-SAR and visual photography for 3D modelling of an Alpine glacier surface kinematics

    Science.gov (United States)

    Dematteis, Niccolò; Luzi, Guido; Giordan, Daniele; Zucca, Francesco; Allasia, Paolo

    2017-04-01

    We present the 3-dimensional modelling of a glacier kinematics, obtained by coupling the results of two monitoring campaigns, simultaneously collecting data from two different and independent remote sensing devices, focused on the surface deformation of the Planpincieux glacier, on the Italian side of the Mont Blanc massif. The analysed period lasted 25 days and occurred in correspondence of the beginning of the Alpine cold season. The unstable weather conditions, affecting both the monitored surfaces and the signal propagation, demanded an accurate understanding of the atmospheric effect and the development of a specific correction procedure for radar data. The considered devices are a low-cost optical photography station (OPS) and a ground-based synthetic aperture radar (GB-SAR). The OPS is placed frontally to the glacier surface and measures the daily motion components orthogonal to the line of sight (LOS). The processing is performed through spatial cross-correlation between consecutive images, acquired at the same hours to limit shadow effects. The images are orthorectified on a 1 m-resolution digital surface model (DSM) of the glacier and a pixel-to-metric conversion is performed. The GB-SAR acquires data every 16 minutes. The GB-SAR location is decided aiming at maximising the parallel condition to the LOS and the estimated direction of the main flow. The main processing steps include i) a coherence-driven pixel-selection criterion to identify glacier areas, ii) 2D unwrapping algorithm, iii) atmosphere phase screen (APS) filtering with a newly 2D polynomial model, function of the elevation. The radar maps are also georeferenced on the DSM. Finally, from the 3 different components of the glacier surface motion it is possible to reconstruct the actual deformation vector. The results are mapped on the DSM. The proposed method allows to determine the evolution of the 3-dimensional kinematics of the observed surface; it can be applied in general to the

  2. The Shadow of Big Data: Data-Citizenship and Exclusion

    DEFF Research Database (Denmark)

    Rossi, Luca; Hjelholt, Morten; Neumayer, Christina

    2016-01-01

    The shadow of Big Data: data-citizenship and exclusion Big data are understood as being able to provide insights on human behaviour at an individual as well as at an aggregated societal level (Manyka et al. 2011). These insights are expected to be more detailed and precise than anything before...... thanks to the large volume of digital data and to the unobstrusive nature of the data collection (Fishleigh 2014). Within this perspective, these two dimensions (volume and unobstrusiveness) define contemporary big data techniques as a socio-technical offering to society, a live representation of itself....... More precisely, within a system theory approach (Luhmann 1982, 2010), large-scale big data work as a boundary-drawing operation where the difference between the system and its environment is reproduced. Here the result of system observation is defined by what is made visible as (big) data. Within...

  3. AN ANALYSIS OF THE SHADOW ECONOMY IN EU COUNTRIES

    Directory of Open Access Journals (Sweden)

    Brindusa Mihaela Tudose

    2016-08-01

    Full Text Available The paper aims at analysing the dimension of the underground economy in the EU states between 2003 and 2015. In order to achieve this goal, we use qualitative and quantitative methods. In the first two sections of the study we resort to conceptualisation and bring up to date scientific contributions in the field of the shadow economy both in terms of its definition and the methods of quantifying the phenomenon. In the third section, based on the results of the latest research, we identify the dynamics of the underground economy on three levels: the EU-15 (before and after 2005; the EU-10 (before and after the accession of 10 countries in 2005 and the EU-3 (before and after 2007. The main conclusion is that regardless of the reporting level (national, European, world, the real size of the underground economy remains unknown.

  4. Rainforest metropolis casts 1,000-km defaunation shadow.

    Science.gov (United States)

    Tregidgo, Daniel J; Barlow, Jos; Pompeu, Paulo S; de Almeida Rocha, Mayana; Parry, Luke

    2017-08-08

    Tropical rainforest regions are urbanizing rapidly, yet the role of emerging metropolises in driving wildlife overharvesting in forests and inland waters is unknown. We present evidence of a large defaunation shadow around a rainforest metropolis. Using interviews with 392 rural fishers, we show that fishing has severely depleted a large-bodied keystone fish species, tambaqui (Colossoma macropomum), with an impact extending over 1,000 km from the rainforest city of Manaus (population 2.1 million). There was strong evidence of defaunation within this area, including a 50% reduction in body size and catch rate (catch per unit effort). Our findings link these declines to city-based boats that provide rural fishers with reliable access to fish buyers and ice and likely impact rural fisher livelihoods and flooded forest biodiversity. This empirical evidence that urban markets can defaunate deep into rainforest wilderness has implications for other urbanizing socioecological systems.

  5. Shadow Detection Based on Regions of Light Sources for Object Extraction in Nighttime Video

    Directory of Open Access Journals (Sweden)

    Gil-beom Lee

    2017-03-01

    Full Text Available Intelligent video surveillance systems detect pre-configured surveillance events through background modeling, foreground and object extraction, object tracking, and event detection. Shadow regions inside video frames sometimes appear as foreground objects, interfere with ensuing processes, and finally degrade the event detection performance of the systems. Conventional studies have mostly used intensity, color, texture, and geometric information to perform shadow detection in daytime video, but these methods lack the capability of removing shadows in nighttime video. In this paper, a novel shadow detection algorithm for nighttime video is proposed; this algorithm partitions each foreground object based on the object’s vertical histogram and screens out shadow objects by validating their orientations heading toward regions of light sources. From the experimental results, it can be seen that the proposed algorithm shows more than 93.8% shadow removal and 89.9% object extraction rates for nighttime video sequences, and the algorithm outperforms conventional shadow removal algorithms designed for daytime videos.

  6. REMOVING SHADOWS FROM HIGH-RESOLUTION URBAN AERIAL IMAGES BASED ON COLOR CONSTANCY

    Directory of Open Access Journals (Sweden)

    Q. Ye

    2012-08-01

    Full Text Available A method is explored to remove tall building shadows in true color and color infrared urban aerial images based on the theory of color constancy. This paper first uses the specthem ratio and Otsu threshold segmentation methods to detect building shadows on urban aerial true color and color infrared aerial images. Then, based on the shadow detection result, one of the color constancy algorithms SoG (Shades of Gray is used to remove the shadows in aerial images with different p values of the Minkowski norm. Finally, the shadow removal results with different p values have been compared by brightness, contrast and average gradients. The experiments show that the result of this method based on color constancy has a good visual effect, and different from general scene image shadow removal, the aerial images get the best shadow removal result when p is 2. It means the two types of aerial images should not be simply regarded as gray world images.

  7. SHADOW EFFECT ON PHOTOVOLTAIC POTENTIALITY ANALYSIS USING 3D CITY MODELS

    Directory of Open Access Journals (Sweden)

    N. Alam

    2012-07-01

    Full Text Available Due to global warming, green-house effect and various other drawbacks of existing energy sources, renewable energy like Photovoltaic system is being popular for energy production. The result of photovoltaic potentiality analysis depends on data quality and parameters. Shadow rapidly decreases performance of the Photovoltaic system and it always changes due to the movement of the sun. Solar radiation incident on earth's atmosphere is relatively constant but the radiation at earth's surface varies due to absorption, scattering, reflection, change in spectral content, diffuse component, water vapor, clouds and pollution etc. In this research, it is being investigated that how efficiently real-time shadow can be detected for both direct and diffuse radiation considering reflection and other factors in contrast with the existing shadow detection methods using latest technologies and what is the minimum quality of data required for this purpose. Of course, geometric details of the building geometry and surroundings directly affect the calculation of shadows. In principle, 3D city models or point clouds, which contain roof structure, vegetation, thematically differentiated surface and texture, are suitable to simulate exact real-time shadow. This research would develop an automated procedure to measure exact shadow effect from the 3D city models and a long-term simulation model to determine the produced energy from the photovoltaic system. In this paper, a developed method for detecting shadow for direct radiation has been discussed with its result using a 3D city model to perform a solar energy potentiality analysis.

  8. An IMU-Aided Body-Shadowing Error Compensation Method for Indoor Bluetooth Positioning.

    Science.gov (United States)

    Deng, Zhongliang; Fu, Xiao; Wang, Hanhua

    2018-01-20

    Research on indoor positioning technologies has recently become a hotspot because of the huge social and economic potential of indoor location-based services (ILBS). Wireless positioning signals have a considerable attenuation in received signal strength (RSS) when transmitting through human bodies, which would cause significant ranging and positioning errors in RSS-based systems. This paper mainly focuses on the body-shadowing impairment of RSS-based ranging and positioning, and derives a mathematical expression of the relation between the body-shadowing effect and the positioning error. In addition, an inertial measurement unit-aided (IMU-aided) body-shadowing detection strategy is designed, and an error compensation model is established to mitigate the effect of body-shadowing. A Bluetooth positioning algorithm with body-shadowing error compensation (BP-BEC) is then proposed to improve both the positioning accuracy and the robustness in indoor body-shadowing environments. Experiments are conducted in two indoor test beds, and the performance of both the BP-BEC algorithm and the algorithms without body-shadowing error compensation (named no-BEC) is evaluated. The results show that the BP-BEC outperforms the no-BEC by about 60.1% and 73.6% in terms of positioning accuracy and robustness, respectively. Moreover, the execution time of the BP-BEC algorithm is also evaluated, and results show that the convergence speed of the proposed algorithm has an insignificant effect on real-time localization.

  9. A method for quantifying cloud immersion in a tropical mountain forest using time-lapse photography

    Science.gov (United States)

    Bassiouni, Maoya; Scholl, Martha A.; Torres-Sanchez, Angel J.; Murphy, Sheila F.

    2017-01-01

    Quantifying the frequency, duration, and elevation range of fog or cloud immersion is essential to estimate cloud water deposition in water budgets and to understand the ecohydrology of cloud forests. The goal of this study was to develop a low-cost and high spatial-coverage method to detect occurrence of cloud immersion within a mountain cloud forest by using time-lapse photography. Trail cameras and temperature/relative humidity sensors were deployed at five sites covering the elevation range from the assumed lifting condensation level to the mountain peaks in the Luquillo Mountains of Puerto Rico. Cloud-sensitive image characteristics (contrast, the coefficient of variation and the entropy of pixel luminance, and image colorfulness) were used with a k-means clustering approach to accurately detect cloud-immersed conditions in a time series of images from March 2014 to May 2016. Images provided hydrologically meaningful cloud-immersion information while temperature-relative humidity data were used to refine the image analysis using dew point information and provided temperature gradients along the elevation transect. Validation of the image processing method with human-judgment based classification generally indicated greater than 90% accuracy. Cloud-immersion frequency averaged 80% at sites above 900 m during nighttime hours and 49% during daytime hours, and was consistent with diurnal patterns of cloud immersion measured in a previous study. Results for the 617 m site demonstrated that cloud immersion in the Luquillo Mountains rarely occurs at the previously-reported cloud base elevation of about 600 m (11% during nighttime hours and 5% during daytime hours). The framework presented in this paper will be used to monitor at a low cost and high spatial resolution the long-term variability of cloud-immersion patterns in the Luquillo Mountains, and can be applied to ecohydrology research at other cloud-forest sites or in coastal ecosystems with advective sea

  10. Shapes and Positions of Black Hole Shadows in Accretion Disks and Spin Parameters of Black Holes

    OpenAIRE

    Takahashi, Rohta

    2004-01-01

    Can we determine a spin parameter of a black hole by observation of a black hole shadow in an accretion disk? In order to answer this question, we make a qualitative analysis and a quantitative analysis of a shape and a position of a black hole shadow casted by a rotating black hole on an optically thick accretion disk and its dependence on an angular momentum of a black hole. We have found black hole shadows with a quite similar size and a shape for largely different black hole spin paramete...

  11. Cold Nuclear Matter effects on J/psi production at RHIC: comparing shadowing models

    Energy Technology Data Exchange (ETDEWEB)

    Ferreiro, E.G.; /Santiago de Compostela U.; Fleuret, F.; /Ecole Polytechnique; Lansberg, J.P.; /SLAC; Rakotozafindrabe, A.; /SPhN, DAPNIA, Saclay

    2009-06-19

    We present a wide study on the comparison of different shadowing models and their influence on J/{psi} production. We have taken into account the possibility of different partonic processes for the c{bar c}-pair production. We notice that the effect of shadowing corrections on J/{psi} production clearly depends on the partonic process considered. Our results are compared to the available data on dAu collisions at RHIC energies. We try different break up cross section for each of the studied shadowing models.

  12. Use of Shadowing-Based Learning in an Allied Health Microbiology Course

    Directory of Open Access Journals (Sweden)

    Alex A. Lowrey

    2016-05-01

    Full Text Available Students in an undergraduate microbiology course for health professions majors perform a shadowing-based learning exercise for their course project. Students accomplish this by shadowing a health care professional of their choice, specifically incorporating basic microbiological concept themes into their observations. These concept themes include the biological nature, health effects, detection, and control of microorganisms. Upon completion of the shadowing experience, students present a concise report, which is graded on how well the students connect course scientific concepts with actual clinical practice.

  13. Female body as a fetish in Helmut Newton's photography

    Directory of Open Access Journals (Sweden)

    Pantović Katarina

    2017-01-01

    Full Text Available The paper illuminates some of the principles by which Helmut Newton's photographic poetics functions. It is examined from the perspectives of recent art history, feminist critique and psychoanalytic theory. His photographs came to a standstill not far from pornography, yet they stayed within the jet-set community, reflecting at the same time the sexual revolution in the 60s and 70s of the twentieth century and the rising of the fashion and film industries and other Western emancipatory movements. Newton's obscure photojournalism provoked conventions, presenting the female body as a fetish and object of erotic pleasure, affirming, nonetheless, a new feminine self-consciousness and freedom. Thus, he constituted modern eroticism by connecting fetishism, voyeurism and sadomasochism, creating a provocative hybrid photography that embraced fashion, eroticism and portrait, hence documenting, in highly stylistic manner, the decadency and eccentricity of the lifestyle of the rich.

  14. Methodology of high-resolution photography for mural condition database

    Science.gov (United States)

    Higuchi, R.; Suzuki, T.; Shibata, M.; Taniguchi, Y.

    2015-08-01

    Digital documentation is one of the most useful techniques to record the condition of cultural heritage. Recently, high-resolution images become increasingly useful because it is possible to show general views of mural paintings and also detailed mural conditions in a single image. As mural paintings are damaged by environmental stresses, it is necessary to record the details of painting condition on high-resolution base maps. Unfortunately, the cost of high-resolution photography and the difficulty of operating its instruments and software have commonly been an impediment for researchers and conservators. However, the recent development of graphic software makes its operation simpler and less expensive. In this paper, we suggest a new approach to make digital heritage inventories without special instruments, based on our recent our research project in Üzümlü church in Cappadocia, Turkey. This method enables us to achieve a high-resolution image database with low costs, short time, and limited human resources.

  15. Calculation of holograms from elemental images captured by integral photography.

    Science.gov (United States)

    Mishina, Tomoyuki; Okui, Makoto; Okano, Fumio

    2006-06-10

    We describe a method in which holograms can be produced by calculation from images captured by integral photography (IP). We present a basic algorithm obtained by simulating IP reconstruction, in which conditions are set so as not to cause aliasing in the holograms after the calculations. To reduce the calculation load, we also propose a way to limit the range of calculation considering the distribution of light and a way to shift the optical field on the exit plane of microlenses in a lens array. Finally, by optical experiments, we confirm that three-dimensional images can be reconstructed from holograms calculated from an integral photograph of a real object captured with an IP camera.

  16. The uses of photography in clinical nursing practice and research: a literature review.

    Science.gov (United States)

    Riley, Robin G; Manias, Elizabeth

    2004-11-01

    The aim of this paper is to report a study to identify themes and provide a 'snap-shot' of the scope and uses of photography in clinical nursing practice and research. Despite the dominance of vision as a way of understanding the world in Western societies, the applications of photography in clinical nursing practice and research have not been well synthesized or reported in the literature. A computerized search of CINAHL database was performed using the terms photographs, photography, photographic, photovoice, videorecording and videotaping. Hand searching for additional citations was also undertaken. The identified papers on photography were categorized into broad themes that reflected the different applications to which photography had been applied: documentation and surveillance; therapeutic intervention; teaching, learning and evaluating performance; research methods; and descriptive and instructional literature. Approaches to the use of photography, as recorded in the nursing literature, are broad and include: wound surveillance, covert patient surveillance, photo essay, art therapy, self-portraits, life albums, simulated recall, participant observation, photovoice, photo hermeneutics, production of research scenarios, and video modelling. The most common applications of photography in nursing and related journals include photo elicitation to promote understanding in research, videorecording as a method of teaching and learning, and as a method of observation, with more creative approaches tending to be employed in health professions other than nursing. Few reports gave explanations of how researchers negotiated ethical concerns when seeking approval for studies in clinical settings, and few gave details of the processes of data analysis.

  17. The Perceptual Basis of Some Rules of Thumb in Photography

    Directory of Open Access Journals (Sweden)

    Martin S. Banks

    2011-05-01

    Full Text Available We communicate increasingly with visual imagery such as realistic pictures (e.g., photographs, computer graphic images, perspective drawings and paintings. People are readily able to interpret pictures, but the means by which they do so is poorly understood. Photographers utilize many guidelines for creating natural-looking pictures. One guideline concerns the lens focal length required to produce pictures that are not spatially distorted. Photography texts recommend choosing a focal length of 50mm. There are two phenomena related to this guideline. One is perceived spatial distortions in wide-angle (short focal length pictures. I will argue that the perceived distortions are caused by the perceptual mechanisms people employ to take into account oblique viewing positions. The second phenomenon is perceived depth in pictures taken with different focal lengths. The textbooks argue that pictures taken with short focal lengths expand perceived depth and those taken with long focal lengths compress it. I will argue that these effects are due to a combination of the viewing geometry and peoples' viewing. Another guideline concerns the camera aperture and depth-of-field blur. Photography textbooks do not describe a quantitative rule and treat the magnitude of depth-of-field blur as arbitrary. I examine apertures, lenses, and image formation. From that examination, I argue that there is a natural relationship between depth-of-field blur and the 3D layout of the photographed scene. Human viewers are sensitive to this relationship. In particular, depicted scenes are perceived differently depending on the relationship between blur and 3D layout. Understanding the perceptual basis of these guidelines provides insight into how to construct photographs, perspective paintings, and computer graphic images for more effective visual communication.

  18. Duchenne De Boulogne: a pioneer in neurology and medical photography.

    Science.gov (United States)

    Parent, André

    2005-08-01

    Guillaume-Benjamin-Amand Duchenne was born 200 years ago in Boulogne-sur-Mer (Pas-de-Calais, France). He studied medicine in Paris and became a physician in 1831. He practiced general medicine in his native town for about 11 years and then returned to Paris to initiate pioneering studies on electrical stimulation of muscles. Duchenne used electricity not only as a therapeutic agent, as it was commonly the case earlier in the 19th century, but chiefly as a physiological investigation tool to study the anatomy of the living body. Without formal appointment he visited hospital wards across Paris searching for rare cases of neuromuscular disorders. He built a portable electrical device that he used to functionally map all bodily muscles and to study their coordinating action in health and disease. He gave accurate descriptions of many neuromuscular disorders, including pseudohypertrophic muscular dystrophy to which his name is still attached (Duchenne muscular dystrophy). He also invented a needle system (Duchenne's histological harpoon) for percutaneous sampling of muscular tissue without anesthesia, a forerunner of today's biopsy. Duchenne summarized his work in two major treatises entitled De l'électrisation localisée (1855) and Physiologie des mouvements (1867). Duchenne's iconographic work stands at the crossroads of three major discoveries of the 19th century: electricity, physiology and photography. This is best exemplified by his investigation of the mechanisms of human physiognomy in which he used localized faradic stimulation to reproduce various forms of human facial expression. The album that complements his book on this issue is considered a true incunabulum of photography. Duchenne de Boulogne, a shy but hard-working, acute and ingenious observer, became one of most original clinicians of the 19th century. He died in Paris in 1875.

  19. Mapping Urban Ecosystem Services Using High Resolution Aerial Photography

    Science.gov (United States)

    Pilant, A. N.; Neale, A.; Wilhelm, D.

    2010-12-01

    Ecosystem services (ES) are the many life-sustaining benefits we receive from nature: e.g., clean air and water, food and fiber, cultural-aesthetic-recreational benefits, pollination and flood control. The ES concept is emerging as a means of integrating complex environmental and economic information to support informed environmental decision making. The US EPA is developing a web-based National Atlas of Ecosystem Services, with a component for urban ecosystems. Currently, the only wall-to-wall, national scale land cover data suitable for this analysis is the National Land Cover Data (NLCD) at 30 m spatial resolution with 5 and 10 year updates. However, aerial photography is acquired at higher spatial resolution (0.5-3 m) and more frequently (1-5 years, typically) for most urban areas. Land cover was mapped in Raleigh, NC using freely available USDA National Agricultural Imagery Program (NAIP) with 1 m ground sample distance to test the suitability of aerial photography for urban ES analysis. Automated feature extraction techniques were used to extract five land cover classes, and an accuracy assessment was performed using standard techniques. Results will be presented that demonstrate applications to mapping ES in urban environments: greenways, corridors, fragmentation, habitat, impervious surfaces, dark and light pavement (urban heat island). Automated feature extraction results mapped over NAIP color aerial photograph. At this scale, we can look at land cover and related ecosystem services at the 2-10 m scale. Small features such as individual trees and sidewalks are visible and mappable. Classified aerial photo of Downtown Raleigh NC Red: impervious surface Dark Green: trees Light Green: grass Tan: soil

  20. Ergonomics Calibration Training Utilizing Photography for Dental Hygiene Faculty Members.

    Science.gov (United States)

    Partido, Brian B

    2017-10-01

    Dental and dental hygiene clinical faculty members often do not provide consistent instruction, especially since most procedures involve clinical judgment. Although instructional variations frequently translate into variations in student performance, the effect of inconsistent instruction is unknown, especially related to ergonomics. The aim of this study was to determine whether photography-assisted calibration training would improve interrater reliability among dental hygiene faculty members in ergonomics evaluation. The photography-assisted ergonomics calibration program incorporated features to improve accessibility and optimize the quality of the training. The study used a two-group repeated measures design with a convenience sample of 11 dental hygiene faculty members (eight full-time and three part-time) during the autumn 2016 term at one U.S. dental school. At weeks one and seven, all participants evaluated imaged postures of five dental students using a modified-dental operator posture assessment instrument. During weeks three and five, training group participants completed calibration training using independent and group review of imaged postures. All pre-training and post-training evaluations were evaluated for interrater reliability. Two-way random effects intraclass coefficient (ICC) values were calculated to measure the effects of the training on interrater reliability. The average measure of ICC of the training group improved from 0.694 with a 95% confidence interval (CI) of 0.001 to 0.965 (F(4,8)=3.465, p>0.05) to 0.766 with a 95% CI of 0.098 to 0.972 (F(4,8)=7.913, pphotography-assisted calibration training with the opportunity to reconcile different opinions resulted in improved agreement among these faculty members.