WorldWideScience

Sample records for vmm-based memory shadowing

  1. Shaping the Jewish South African Story: Imprints of Memories, Shadows and Silences

    Directory of Open Access Journals (Sweden)

    Phyllis Sakinofsky

    2009-11-01

    Full Text Available Storytelling is the thread connecting history, memory and imagination, piecing together alternate truths, unravelling forgotten memories, and making meaning for the teller and her audience. This paper examines the relationship between theory, history and imagination and their combined influence on this writer’s work of fiction. I was born into the South African Jewish community, a homogenous group that migrated from Lithuania around the turn of the twentieth century to seek an alternative to growing antisemitism and poverty, only to find themselves enmeshed in another form of oppression – apartheid – but this time embedded on the side of the oppressor. Antisemitism, the Holocaust, and apartheid permeated the psyche of all Jews in South Africa, and yet the imprints of shadows and silences exhibited themselves in contrasting responses to oppression – ranging from those who supported and benefited from apartheid to opponents and activists who fought the system from within and without. This article is the based on the unexpected outcomes of my PhD which comprised two components: a novel and accompanying dissertation. What I found was that the two streams – creative and academic – fed and nurtured one another to bring to the surface stories that had been generated by academic reading, personal, collective and submerged memories of a diasporic community, and imagination.

  2. An Invisible Man (Ralph Ellison reincarnates in Manchild in the Promised Land (Claude Brown and becomes Shadows of Your Black Memory (Donato Ndongo

    Directory of Open Access Journals (Sweden)

    Rosetta Codling

    2011-11-01

    Full Text Available Ralph Ellison’s allegorical journey in Invisible Man (1994 launched a new era in African-American culture and Black literacy for the entire world in 1952. In 1965, Ellison’s tragic, Diasporic hero appears to have experienced a reincarnation in the epic of Manchild in the Promised Land (1999 by Claude Brown. Currently, lingering in the caverns of Shadows of Your Black Memory (2007, past and present, Donato Ndongo’s tragic, Diasporic hero (of Equatorial Guinean heritage prompts us to relive the course of colonialism and neocolonialism ‘of the mind’ in this…. the new millennium. This paper addresses the trilogy of resistance writing in Ellison’s Invisible Man, Brown’s Manchild in the Promised Land, and Ndongo’s Shadows of Your Black Memory. The experiences of the writers, political issues illustrated, and the impact upon the Black literary landscape (universal will be explored.

  3. A Memory of Shadows and of Stone. Traumatic Ruins, Conservation, Social Processes

    Directory of Open Access Journals (Sweden)

    Nino Sulfaro

    2014-12-01

    Full Text Available Considering the scars caused by many terrible traumatic events, such as the atomic bomb, the Holocaust, genocides, massacres, and also deep socio-economic transformations, the notion of memory in the contemporary age is nearly always the result of a conflict between the conservation of some elements of the past and the oblivion of others. The ruin or the place of a tragedy is no longer merely a trace of a terrible past but, through a resemantization process, it becomes a sign, which is transmittable to the future. This introduces some questions to the issue of traumatic ruin: what are the social implications of ‘memorializing’ the trauma? Who decides what kind of traces of the past to deliver to the future? What is the role of conservation and architectural restoration in these processes? The present paper focuses on the possible practices in the processes of the representation of the past, with special regard to the relationship between places/buildings, memory and social processes. In particular, the paper deals with the consequences of practices involving a reinterpretation of the past and, practices aimed at leaving the signs of traumatic events visible on a building, a monument or a place: practices which, as they involve oblivion and remembrance, describe the contemporary condition of memory.

  4. 基于VMM的文件完整性监控系统的设计与实现%Design and Implementation of VMM-based File Integrity Monitoring System

    Institute of Scientific and Technical Information of China (English)

    陈威; 王晖

    2012-01-01

    A virtual machine monitor(VMM) has strong control ability and its characteristic of isolation, and can solve open question in the existing file integrity monitoring systems, A new VMM-based method for file integrity protecting system was proposed, which is isolated between the system and the guest systems. This method should pre-configure the files to be protected and can avoid the attack to these files from the malicious codes. In this scheme of file integrity protection, the system can intercept all the access attempts to the protected files in real-time by designing and implanting the "detector" and "reversed file locator" into the isolated layer of the virtual machine, and achieves the strategy of pre-protection.%虚拟机监控器(VMM)具有强控制性、隔离性的特点.针对现有文件完整性监控系统中存在的缺陷,提出了一种新的基于VMM且与客户机相隔离的文件完整性保护方法,该方法能够保护用户的敏感文件,特别是文件完整性监控系统本身,使其免受恶意代码的攻击.这种基于虚拟机监控器的文件完整性保护解决方案,在虚拟机隔离层中通过设计和嵌入的“探测器”和“文件逆向定位器”两种关键技术,能够实时地探测到对被保护文件的所有访问企图,从而实现预置的保护策略.

  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. JERKO SKRAČIĆ: A CROATIAN WRITER IN THE SHADOW OF MEMORY (FIRST PART: BIOGRAPHY, FROM THE WRITTEN WORD TO THE AUTHOR)

    OpenAIRE

    Skračić, Tomislav

    2008-01-01

    The article "Jerko Skračić – a Croatian writer in the shadow of memory" consists of two parts. This, first, part represents an attempt to reconstruct the biography ofthe writer and newspaperman Jerolim Skračić (1918-1947?). The article has been written according to the methodological principle of "from the written word to the author". For that purpose the article primarily targets the writer's literary works and later his autobiographical writings. Reports made by his kin as well as some now ...

  7. Dostoevsky's Shadows

    Directory of Open Access Journals (Sweden)

    Ioana Cristina Nicolae

    2016-04-01

    Full Text Available In this paper, I bring to light Jung’s Shadow archetype in Dostoevsky’s works and also analyzes their implications in the structure of his characters. Taking into account that the Russian writer’s creation is vast, I shall select a limited number of his works, namely ‘The Possessed’; ‘Crime and Punishment’; ‘The Brothers Karamazov’; ‘Notes from Underground’ and ‘The Double’. We are all burdened with our Shadow and must strive to overcome it, but what happens if we fail or never even try to master it? Raskolnikov’s attempt to free himself from the chains of his Shadow was too late, he had already committed the murder, but not in vain, he succeeded in redeeming himself, and so his effort must be taken into account. This does not help him to avoid the punishment, but offers him a chance after serving it. On the other hand, Smerdyakov’s case is different: he made no attempt to overcome his Shadow, the only argument that he brought in his favor being that he acted fuelled by the desire of fulfilling his brother’s wish. It is clear that, he has no chance for a better future and the fault lies with him because he did not create that chance. Dostoevsky’s characters always seem to be ruled by a tragic destiny, an unlucky fate from which they cannot escape.

  8. Shadow Soldiering

    DEFF Research Database (Denmark)

    Mynster Christensen, Maya

    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......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...

  9. 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

  10. 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...

  11. Shadowing in dynamical systems

    CERN Document Server

    Pilyugin, Sergei Yu

    1999-01-01

    This book is an introduction to the theory of shadowing of approximate trajectories in dynamical systems by exact ones. This is the first book completely devoted to the theory of shadowing. It shows the importance of shadowing theory for both the qualitative theory of dynamical systems and the theory of numerical methods. Shadowing Methods allow us to estimate differences between exact and approximate solutions on infinite time intervals and to understand the influence of error terms. The book is intended for specialists in dynamical systems, for researchers and graduate students in the theory of numerical methods.

  12. Inverse periodic shadowing properties

    CERN Document Server

    Osipov, Alexey V

    2011-01-01

    We consider inverse periodic shadowing properties of discrete dynamical systems generated by diffeomorphisms of closed smooth manifolds. We show that the $C^1$-interior of the set of all diffeomorphisms having so-called inverse periodic shadowing property coincides with the set of $\\Omega$-stable diffeomorphisms. The equivalence of Lipschitz inverse periodic shadowing property and hyperbolicity of the closure of all periodic points is proved. Besides, we prove that the set of all diffeomorphisms that have Lipschitz inverse periodic shadowing property and whose periodic points are dense in the nonwandering set coincides with the set of Axiom A diffeomorphisms.

  13. Gas and Shadow Swing

    Science.gov (United States)

    Tsai, Chi-Hung; Lai, Mei-Yi; Liu, Che-Wei; Huang, Shiang-Yin; Lin, Che-Yu; Yeh, Jeng-Sheng

    In our digital art, we design a folding fan as an interactive magic device. You can use it to play with gas around the world of illusions. Although gas could not be seen in our real world, we still want to interact with it in our illusions by the element of bubble shadows. Opening and swinging the folding fan can blow the bubble shadows away; closing and swinging it can break bubbles. If the magic fan touches the shadow of gas, the bubble shadows will explode and release colorful particles to surround you. Those actions are controlled and located by our circuits with Arduino board.

  14. 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.

  15. Stochastic Shadowing and Stochastic Stability

    OpenAIRE

    Todorov, Dmitry

    2014-01-01

    The notion of stochastic shadowing property is introduced. Relations to stochastic stability and standard shadowing are studied. Using tent map as an example it is proved that, in contrast to what happens for standard shadowing, there are significantly non-uniformly hyperbolic systems that satisfy stochastic shadowing property.

  16. 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.

  17. An Empirical Study into the Effects of Shadowing Exercise on Short-Term Memory in Interpretation%影子训练对提高口译初学者短期记忆作用研究--以浙江农林大学英语系大三学生为例

    Institute of Scientific and Technical Information of China (English)

    王庆虹; 梅吟雪; 琚盼

    2014-01-01

    Shadowing exercise, one of teaching methods to strengthen speaking and listening capability and memory during inter-pretation, has long been limited in the field of simultaneous interpretation training. This article elaborates the influence of shadow-ing exercise by carrying out an experiment and making a thoroughly analysis about its results. Meanwhile, the article tries to re-evaluate the role of shadowing and emphasize some of its notable effects and therefore wish to apply it into interpretation study of students.%影子训练作为口译专业训练学生听说能力和记忆能力的一种教学手段一直以来只局限于同声传译训练中。该文以口译训练中的影子训练为切入点,设计实验,深入分析实验结果并探讨影子训练对口译短期记忆的实际作用。并把它推广运用于口译学习中以期更好的指导口译训练,提高口译初学者的口译质量。

  18. 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...

  19. Memory

    Science.gov (United States)

    ... it has to decide what is worth remembering. Memory is the process of storing and then remembering this information. There are different types of memory. Short-term memory stores information for a few ...

  20. Observe Your Shadow

    Science.gov (United States)

    Rovšek, Barbara

    2016-04-01

    Observe Your Shadow was the title of an observational experiment that was, among others, conducted in the scope of the past year's (2014-2015) first Slovene science competition for elementary school pupils between the ages of 6 and 13. The main reason for establishing a new science competition was popularization of science and its experimental methods, particularly among elementary school students. Elementary school teachers are not generally specialists in science, but rather have (and should have) extremely wide scopes of interests and competencies. By providing them with ideas and instructions for science experiments, we aim to enrich regular school lessons. In the first year alone, the competition took place in over half of Slovene elementary schools, with a total of 9000 participating students. In this paper we shall report about pupils' responses to tasks related to one of the experiments, namely, observation of their shadows on a sunny day.

  1. Forming Spirals From Shadows

    Science.gov (United States)

    Kohler, Susanna

    2016-07-01

    What causes the large-scale spiral structures found in some protoplanetary disks? Most models assume theyre created by newly-forming planets, but a new study suggests that planets might have nothing to do with it.Perturbations from Planets?In some transition disks protoplanetary disks with gaps in their inner regions weve directly imaged large-scale spiral arms. Many theories currently attribute the formation of these structures to young planets: either the direct perturbations of a planet embedded in the disk cause the spirals, or theyre indirectly caused by the orbit of a planetary body outside of the arms.Another example of spiral arms detected in a protoplanetary disk, MWC 758. [NASA/ESA/ESO/M. Benisty et al.]But what if you could get spirals without any planets? A team of scientists led by Matas Montesinos (University of Chile) have recently published a study in which they examine what happens to a shadowed protoplanetary disk.Casting Shadows with WarpsIn the teams setup, they envision a protoplanetary disk that is warped: the inner region is slightly tilted relative to the outer region. As the central star casts light out over its protoplanetary disk, this disk warping would cause some regions of the disk to be shaded in a way that isnt axially symmetric with potentially interesting implications.Montesinos and collaborators ran 2D hydrodynamics simulations to determine what happens to the motion of particles within the disk when they pass in and out of the shadowed regions. Since the shadowed regions are significantly colder than the illuminated disk, the pressure in these regions is much lower. Particles are therefore accelerated and decelerated as they pass through these regions, and the lack of axial symmetry causes spiral density waves to form in the disk as a result.Initial profile for the stellar heating rate per unit area for one of the authors simulations. The regions shadowed as a result of the disk warp subtend 0.5 radians each (shown on the left

  2. Soft bilateral filtering volumetric shadows using cube shadow maps

    Science.gov (United States)

    Ali, Hatam H.; Sunar, Mohd Shahrizal; Kolivand, Hoshang

    2017-01-01

    Volumetric shadows often increase the realism of rendered scenes in computer graphics. Typical volumetric shadows techniques do not provide a smooth transition effect in real-time with conservation on crispness of boundaries. This research presents a new technique for generating high quality volumetric shadows by sampling and interpolation. Contrary to conventional ray marching method, which requires extensive time, this proposed technique adopts downsampling in calculating ray marching. Furthermore, light scattering is computed in High Dynamic Range buffer to generate tone mapping. The bilateral interpolation is used along a view rays to smooth transition of volumetric shadows with respect to preserving-edges. In addition, this technique applied a cube shadow map to create multiple shadows. The contribution of this technique isreducing the number of sample points in evaluating light scattering and then introducing bilateral interpolation to improve volumetric shadows. This contribution is done by removing the inherent deficiencies significantly in shadow maps. This technique allows obtaining soft marvelous volumetric shadows, having a good performance and high quality, which show its potential for interactive applications. PMID:28632740

  3. Shadows of WWII

    Directory of Open Access Journals (Sweden)

    Yumiko Sato

    2010-03-01

    Full Text Available On my initial visit with Shen I discovered that he grew up in China under the Japanese occupation during WWII. How would my nationality affect our therapeutic relationship? As a Japanese music therapist working at hospice in America the shadow of WWII is something I can not avoid. Neither can my patients. For those who lived through the war meeting someone from Japan could bring back powerful emotions, especially when theyre facing their final journeys. This is a story of patients for whom both music and my nationality opened the door to unexpected experiences. All identifying information has been changed to protect peoples confidentiality.

  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. The Moon's Phases and the Self Shadow

    Science.gov (United States)

    Young, Timothy; Guy, Mark

    2008-01-01

    In this article, the authors present a new way of teaching the phases of the Moon. Through the introduction of a "self shadow" (an idea of a shadow that is not well-known), they illuminate students' understanding of the phases of the Moon and help them understand the distinction between the shadows that cause eclipses and the shadows that relate…

  6. 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

  7. 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

  8. Testing the stress shadow hypothesis

    Science.gov (United States)

    Felzer, Karen R.; Brodsky, Emily E.

    2005-05-01

    A fundamental question in earthquake physics is whether aftershocks are predominantly triggered by static stress changes (permanent stress changes associated with fault displacement) or dynamic stresses (temporary stress changes associated with earthquake shaking). Both classes of models provide plausible explanations for earthquake triggering of aftershocks, but only the static stress model predicts stress shadows, or regions in which activity is decreased by a nearby earthquake. To test for whether a main shock has produced a stress shadow, we calculate time ratios, defined as the ratio of the time between the main shock and the first earthquake to follow it and the time between the last earthquake to precede the main shock and the first earthquake to follow it. A single value of the time ratio is calculated for each 10 × 10 km bin within 1.5 fault lengths of the main shock epicenter. Large values of the time ratio indicate a long wait for the first earthquake to follow the main shock and thus a potential stress shadow, whereas small values indicate the presence of aftershocks. Simulations indicate that the time ratio test should have sufficient sensitivity to detect stress shadows if they are produced in accordance with the rate and state friction model. We evaluate the 1989 MW 7.0 Loma Prieta, 1992 MW 7.3 Landers, 1994 MW 6.7 Northridge, and 1999 MW 7.1 Hector Mine main shocks. For each main shock, there is a pronounced concentration of small time ratios, indicating the presence of aftershocks, but the number of large time ratios is less than at other times in the catalog. This suggests that stress shadows are not present. By comparing our results to simulations we estimate that we can be at least 98% confident that the Loma Prieta and Landers main shocks did not produce stress shadows and 91% and 84% confident that stress shadows were not generated by the Hector Mine and Northridge main shocks, respectively. We also investigate the long hypothesized existence

  9. 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.

  10. Shadow of a naked singularity

    Science.gov (United States)

    Ortiz, Néstor; Sarbach, Olivier; Zannias, Thomas

    2015-08-01

    We analyze the redshift suffered by photons originating from an external source, traversing a collapsing dust cloud, and finally being received by an asymptotic observer. In addition, we study the shadow that the collapsing cloud casts on the sky of the asymptotic observer. We find that the resulting redshift and properties of the shadow depend crucially on whether the final outcome of the complete gravitational collapse is a black hole or a naked singularity. In the black hole case, the shadow is due to the high redshift acquired by the photons as they approach the event horizon, implying that their energy is gradually redshifted toward zero within a few crossing times associated with the event horizon radius. In contrast to this, a naked singularity not only absorbs photons originating from the source, but it also emits infinitely redshifted photons with and without angular momenta. This emission introduces an abrupt cutoff in the frequency shift of the photons detected in directions close to the radial one, and it is responsible for the shadow masking the source in the naked singularity case. Furthermore, even though the shadow forms and begins to grow immediately after the observer crosses the Cauchy horizon, it takes many more crossing times than in the black hole case for the source to be occulted from the observer's eyes. We discuss possible implications of our results for testing the weak cosmic censorship hypothesis. Even though at late times the image of the source perceived by the observer looks the same in both cases, the dynamical formation of the shadow and the redshift images has distinct features and time scales in the black hole versus the naked singularity case. For stellar collapse, these time scales seem to be too short to be resolved with existing technology. However, our results may be relevant for the collapse of seeds leading to supermassive black holes.

  11. Random Access Memory Technologies.

    Science.gov (United States)

    1985-02-01

    extreme temperatures. True nonvolatility is offered by the NVRAM or shadow RAM. In the NVRAM , a volatile NMOS static RAM memory cell is merged with the...or reapplied, and no longer require special power sources. The size of the nine-device memory cell required for the NVRAM has limited its capacity to...4K. While 8K NVRAMs are expected in 1985, the 30 . . .’o .-. . high cost of these devices will hamper further development for larger capacity memories

  12. The shadow world of superstring theories

    Science.gov (United States)

    Kolb, E. W.; Turner, M. S.; Seckel, D.

    1985-01-01

    Some possible astrophysical and cosmological implications of 'shadow matter', a form of matter which only interacts gravitationally with ordinary matter and which may or may not be identical in its properties to ordinary matter, are considered. The possible existence, amount, and location of shadow matter in the solar system are discussed, and the significance of shadow matter for primordial nucleosynthesis, macroscopic asymmetry, baryogenesis, double-bubble inflation, and asymmetric microphysics is addressed. Massive shadow states are discussed.

  13. [Pellegrini-Stieda disease (shadow)].

    Science.gov (United States)

    Tkebuchava, G I

    1976-02-01

    The Pellegrini-Stied disease (shadow) (calcification periarthritis of the knee) is characterized by the presence of ossification of the medial condyl of the femur. The author's observations of 51 patients (sportsmen) suffering this lesion are described. The methods of conservative and operative treatment and the results obtained are reported.

  14. The Greatest Shadow on Earth

    Science.gov (United States)

    Hughes, Stephen; Wimmer, Jason; Towsey, Michael; Fahmi, Marco; Winslett, Greg; Dubler, Gabriel; Le Prou, Angela; Loose, David

    2014-01-01

    In a total solar eclipse, the Moon completely covers the Sun, casting a shadow several hundred km wide across the face of the Earth. This paper describes observations of the 14 November 2012 total eclipse of the Sun visible from north Queensland, Australia. The edge of the umbra was captured on video during totality, and this video is provided for…

  15. A spectrum of shadowed mirroring.

    Science.gov (United States)

    Wanamaker, Melissa C

    2012-04-01

    The central focus of this paper is to explore and extend Kohut's theory of maternal mirroring and to place it within the current context of psychoanalytic thinking. Kohut believed a child must experience "positive" mirroring from his or her mother in infancy and beyond to ensure development of a healthy self. Kohut alludes, however, to a possible situation in which the mother's face, metaphorically a mirror, can appear "faceless" to her child. From this I have inferred the concept of what I shall call "shadowed mirroring." Clinical and literary examples show that distorted, "shadowed" mirroring appears on a spectrum, with passive mirroring at one end and hostile (either verbal or nonverbal) mirroring on the other; some individuals experience both. I then consider how "shadowed mirroring," especially hostile mirroring, can be understood within the twin contexts of the overall mother-child relationship and present-day Intersubjective/Relational thinking that is both bidirectional and co-constructed. Shadowed mirroring can lead to severe personality dysfunction along the borderline-narcissistic range, as well as to difficulties in the areas of identity formation, failure of self-cohesiveness, and the blunting of certain humane qualities like empathy.

  16. Video Job Shadows. Project SEED.

    Science.gov (United States)

    Kucinkas, Gene; Noyce, Gary

    Video Job Shadows encourages students to develop questions about a job and offers them the chance to videotape a business person answering those questions about his or her job. The program can be an effective method of teaching high school students about the world of work and the specific requirements and responsibilities of some jobs in their…

  17. Gait identification from invisible shadows

    Science.gov (United States)

    Iwashita, Yumi; Uchino, Koji; Kurazume, Ryo; Stoica, Adrian

    2012-06-01

    This paper introduces a person identification system that uses as input the shadow images of a walking person, as projected by multiple lights(in this application invisible/infrared lights); the system uses a database of examples of shadows images of a number of people who walk. While it is accepted that personal identification has a higher correct classification rate if views from multiple cameras are used, most systems use only one camera, mainly because (i) Installation in real-world environments is easier, less cameras and no need to synchronize cameras, (ii) Computational cost is reduced. In the proposed system, we obtain the advantages of multiple viewpoints with a single camera and additional light sources. More specific, we install multiple infrared lights to project shadows of a subject on the ground and a camera with an infrared transmitting filter mounted in the ceiling inside of a building. Shadow areas, which are projections of one's body on the ground by multiple lights, can be considered as body areas captured from different viewpoints; thus, the proposed system is able to capture multiple projections of the body from a single camera. We explored in other papers the use of sunproduced shadow for identification of people walking freely in the outdoor. In this paper the application scenario is a system installed at the airport in the areas that precedes the immigration checkpoint. Japan already has health monitoring cameras focused on approaching individuals, to determine their health condition; the here described system would also be installed in such a controlled area with restricted walk corridors of walk and controlled lighting. Gait is a remote biometrics and can provide early warning; on another hand it can be used as corroborating evidence in a multi-modal biometrics system. A database of images including shadows for a set of 28 walking people was collected, and the features extracted from shadow areas by affine moment invariants, after which

  18. Object Oriented Shadow Detection and an Enhanced Method for Shadow Removal

    Directory of Open Access Journals (Sweden)

    Divya S Kumar

    2016-06-01

    Full Text Available Remote sensing technology derives information about the earth resources from satellite imagery. In urban areas, mainly the elevated objects are the reason for the appearance of shadows. Shadows are created as the light source has been blocked by something. Shadows lower the quality of images or it may affect the information provided by them. Thus for the correct image interpretation or to extract information it is important to detect shadow regions and restore them. Significant researches has been going on in finding the best shadow detection and removal methods. Many algorithms and methods had been developed so far. Most of them are based on pixel level shadow detection and removal. An object oriented shadow detection and removal resolves the shortcomings of pixel level detection. Existing object oriented method suffers from color casting of images even after the correction. A new method for shadow compensation by image inpainting resolves these color casting problem. Keywords- Shadow detection, shadow removal, Inpainting

  19. Wormhole shadows in rotating dust

    Science.gov (United States)

    Ohgami, Takayuki; Sakai, Nobuyuki

    2016-09-01

    As an extension of our previous work, which investigated the shadows of the Ellis wormhole surrounded by nonrotating dust, in this paper we study wormhole shadows in a rotating dust flow. First, we derive steady-state solutions of slowly rotating dust surrounding the wormhole by solving relativistic Euler equations. Solving null geodesic equations and radiation transfer equations, we investigate the images of the wormhole surrounded by dust for the above steady-state solutions. Because the Ellis wormhole spacetime possesses unstable circular orbits of photons, a bright ring appears in the image, just as in Schwarzschild spacetime. The bright ring looks distorted due to rotation. Aside from the bright ring, there appear weakly luminous complex patterns by the emission from the other side of the throat. These structure could be detected by high-resolution very-long-baseline-interferometry observations in the near future.

  20. Shadow imaging of geosynchronous satellites

    Science.gov (United States)

    Douglas, Dennis Michael

    Geosynchronous (GEO) satellites are essential for modern communication networks. If communication to a GEO satellite is lost and a malfunction occurs upon orbit insertion such as a solar panel not deploying there is no direct way to observe it from Earth. Due to the GEO orbit distance of ~36,000 km from Earth's surface, the Rayleigh criteria dictates that a 14 m telescope is required to conventionally image a satellite with spatial resolution down to 1 m using visible light. Furthermore, a telescope larger than 30 m is required under ideal conditions to obtain spatial resolution down to 0.4 m. This dissertation evaluates a method for obtaining high spatial resolution images of GEO satellites from an Earth based system by measuring the irradiance distribution on the ground resulting from the occultation of the satellite passing in front of a star. The representative size of a GEO satellite combined with the orbital distance results in the ground shadow being consistent with a Fresnel diffraction pattern when observed at visible wavelengths. A measurement of the ground shadow irradiance is used as an amplitude constraint in a Gerchberg-Saxton phase retrieval algorithm that produces a reconstruction of the satellite's 2D transmission function which is analogous to a reverse contrast image of the satellite. The advantage of shadow imaging is that a terrestrial based redundant set of linearly distributed inexpensive small telescopes, each coupled to high speed detectors, is a more effective resolved imaging system for GEO satellites than a very large telescope under ideal conditions. Modeling and simulation efforts indicate sub-meter spatial resolution can be readily achieved using collection apertures of less than 1 meter in diameter. A mathematical basis is established for the treatment of the physical phenomena involved in the shadow imaging process. This includes the source star brightness and angular extent, and the diffraction of starlight from the satellite

  1. Impact of shadow banks on financial contagion

    OpenAIRE

    Yoshiharu Maeno; Kenji Nishiguchi; Satoshi Morinaga; Hirokazu Matsushima

    2014-01-01

    An asset network systemic risk (ANWSER) model is presented to investigate the impact of how shadow banks are intermingled in a financial system on the severity of financial contagion. Particularly, the focus of this study is the impact of the following three representative topologies of an interbank loan network between shadow banks and regulated banks. (1) Random mixing network: shadow banks and regulated banks are intermingled randomly. (2) Asset-correlated mixing network: banks having bigg...

  2. Shadow Banking – International and Domestic Developments

    OpenAIRE

    Josef Manalo; Kate McLoughlin; Carl Schwartz

    2015-01-01

    One of the lessons from the global financial crisis is that systemic risk to the financial system can arise from outside the regular banking system, in so-called ‘shadow banking’. This article reviews post-crisis international and domestic trends in shadow banking, and regulatory efforts to better understand and address potential risks that may arise. In Australia, systemic risks arising from shadow banking appear limited given its relatively small size and minimal links to the banking system...

  3. 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.

  4. Are shadows transparent? An investigation on white, shadows and transparency in pictures

    OpenAIRE

    2009-01-01

    Shadow perception and transparency perception appear to use very similar rules, to the point that from the perceptual point of view shadows have been considered an instance of transparent objects. We claim that in spite of the similarities, shadows ought not to be considered transparent entities. The discussion has consequences both for the issue of the location of shadows, and for the conceptualization of transparency, and it provides insight into the inner complexities of the conceptual str...

  5. Digital gray-level transformation for the reduction of redundant shadows in rotational panoramic radiography.

    Science.gov (United States)

    Hayakawa, Y; Wakoh, M; Yamamoto, K; Ueno, H; Kuroyanagi, K

    1990-08-01

    In rotational panoramic radiography, the tomographic motion in combination with a slit scanning method make an image layer wide. But some objects outside the image layer are hard to blur and they result to redundant shadows. The gray-level transformation, as one form of digital image processing for the reduction of these redundant shadows, was evaluated. Two methods, the gamma transformation and the histogram flattening method, were examined. A drum scanner was used as the image scanner. The panoramic image on the x-ray film was turned into an 8 bit digital image on the image memory, which had the size of a 512 x 480 matrix. In rotational panoramic radiography, there are low density and contrast regions where redundant shadows of the cervical vertebrae and the mandibular ramus are superimposed on the tomographic image. The histogram of the gray-level was suppressed for the lower gray-levels. The stretching of this gray-level distribution was effective in the reducing redundant shadows. When processed by gamma transformation, the smaller gamma coefficient below 1.0 clarified the tomographic image, and when processed by the histogram flattening method, the setting of the level (L) value around 64-128 effectively reduced the redundant shadows. However, the effectiveness of both gray-level transformations was greatest in restricted cases in which the area where redundant shadows were superimposed on the tomographic image was comparatively large.

  6. Fixing the Shadows While Moving the Gnomon

    Science.gov (United States)

    Gangui, Alejandro

    2015-01-01

    It is a common practice to fix a vertical gnomon and study the moving shadow cast by it. This shows our local solar time and gives us a hint regarding the season in which we perform the observation. The moving shadow can also tell us our latitude with high precision. In this paper we propose to exchange the roles and while keeping the shadows…

  7. Diffeomorphisms with Lp-Shadowing Property

    Institute of Scientific and Technical Information of China (English)

    Abbas FAKHARI; Keonhee LEE; Khosro TAJBAKHSH

    2011-01-01

    We give a characterization of structurally stable diffeomorphisms by making use of the notion of Lp-shadowing property. More precisely, we prove that the set of structurally stable diffeo morphisms coincides with the C1-interior of the set of diffeomorphisms having Lp-shadowing property.

  8. Shadow Attenuation With High Dynamic Range Images

    Science.gov (United States)

    Shadow often interferes with accurate image analysis. To mitigate shadow effects in near-earth imagery (2 m above ground level), we created high dynamic range (HDR) nadir images and used them to measure grassland ground cover. HDR composites were created by merging three differentially-exposed image...

  9. 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...

  10. Shadow of rotating regular black holes

    CERN Document Server

    Abdujabbarov, Ahmadjon; Ahmedov, Bobomurat; Ghosh, Sushant G

    2016-01-01

    We study the shadows cast by the different types of rotating regular black holes viz. Ay\\'on-Beato-Garc\\'ia {(ABG)}, Hayward, and Bardeen. These black holes have in addition to the total mass ($M$) and rotation parameter ($a$), different parameters as electric charge ($Q$), deviation parameter ($g$), and magnetic charge ($g_{*}$), respectively. Interestingly, the size of the shadow is affected by these parameters in addition to the rotation parameter. We found that the radius of the shadow in each case decreases monotonically and the distortion parameter increases when the value of these parameters increase. A comparison with the standard Kerr case is also investigated. We have also studied the influence of the plasma environment around regular black holes to discuss its shadow. The presence of the plasma affects the apparent size of the regular black hole's shadow to be increased due to two effects (i) gravitational redshift of the photons and (ii) radial dependence of plasma density.

  11. On the removal of shadows from images.

    Science.gov (United States)

    Finlayson, Graham D; Hordley, Steven D; Lu, Cheng; Drew, Mark S

    2006-01-01

    This paper is concerned with the derivation of a progression of shadow-free image representations. First, we show that adopting certain assumptions about lights and cameras leads to a 1D, gray-scale image representation which is illuminant invariant at each image pixel. We show that as a consequence, images represented in this form are shadow-free. We then extend this 1D representation to an equivalent 2D, chromaticity representation. We show that in this 2D representation, it is possible to relight all the image pixels in the same way, effectively deriving a 2D image representation which is additionally shadow-free. Finally, we show how to recover a 3D, full color shadow-free image representation by first (with the help of the 2D representation) identifying shadow edges. We then remove shadow edges from the edge-map of the original image by edge in-painting and we propose a method to reintegrate this thresholded edge map, thus deriving the sought-after 3D shadow-free image.

  12. Printed shadow masks for organic transistors

    Science.gov (United States)

    Noguchi, Yoshiaki; Sekitani, Tsuyoshi; Someya, Takao

    2007-09-01

    We have manufactured organic field-effect transistors by using shadow masks that are patterned by a screen printing system. The 50-nm-thick pentacene layer is sublimed as a channel in the vacuum system through the shadow mask on the base film with a multilayer patterned by ink-jet. After the deposition of the pentacene layer, the shadow mask is peeled off from the base film without any mechanical damages to the lower structures. The mobility in the saturation regime is 0.4cm2/Vs and the on-off ratio exceeds 105.

  13. Alorithm for Shadow Detection in Real Colour Images

    Directory of Open Access Journals (Sweden)

    Sanjeev Kumar,

    2010-10-01

    Full Text Available 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 detection scheme for color images is presented in this paper. The RBG ellipsoidal region technique is used to detect shadow in colour image.

  14. Fixing the shadows while moving the gnomon

    CERN Document Server

    Gangui, Alejandro

    2016-01-01

    It is a common practice to fix a vertical gnomon and study the moving shadow cast by it. This shows our local solar time and gives us a hint regarding the season in which we perform the observation. The moving shadow can also tell us our latitude with high precision. In this paper we propose to exchange the roles and while keeping the shadows fixed on the ground we will move the gnomon. This lets us understand in a simple way the relevance of the tropical lines of latitude and the behavior of shadows in different locations. We then put these ideas into practice using sticks and threads during a solstice on two sites located on opposite sides of the Tropic of Capricorn.

  15. 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.

  16. 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...

  17. Shadow imaging of geosynchronous satellites: simulation, image reconstruction, and shadow prediction

    Science.gov (United States)

    Douglas, Dennis M.; Hunt, Bobby R.; Sheppard, David G.

    2016-09-01

    Shadow imaging is a technique to obtain highly resolved silhouettes of resident space objects (RSOs) which would otherwise be unattainable using conventional terrestrial based imaging approaches. This is done by post processing the measured irradiance pattern (shadow) cast onto the Earth as the RSO occults a star. The research presented here focuses on shadow imaging of geosynchronous (GEO) satellites with near stationary orbits approximately 36,000 km from the Earth. Shadows pertaining to a set of diverse observing scenarios are simulated and used as inputs to a Fresnel based phase retrieval algorithm. Spatial resolution limits are evaluated and correlated to signal to noise (SNR) metrics. Resolvable feature sizes of less than 1 m are shown to be readily achievable using foreseeable observing scenarios. Initial output from a shadow prediction tool indicates that there are, on average, over 1000 shadows on the Earth on any given time from a single GEO satellite for stars brighter than mv=10. Shadow ground track uncertainties are correlated to stellar astrometric errors. Global and localized shadow track maps are presented demonstrating a high feasibility for future shadow collections.

  18. Investigation of the Stability via Shadowing Property

    Directory of Open Access Journals (Sweden)

    Koh Heejeong

    2009-01-01

    Full Text Available The shadowing property is to find an exact solution to an iterated map that remains close to an approximate solution. In this article, using shadowing property, we show the stability of the following equation in normed group: , where , and is a mapping. And we prove that the even mapping which satisfies the above equation is quadratic and also the Hyers-Ulam stability of the functional equation in Banach spaces.

  19. 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 are...... 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....

  20. In the shadow of death.

    Science.gov (United States)

    Meissner, W W

    1995-08-01

    Death dogged Vincent's footsteps throughout his life, and formed a core component of his unconscious fantasy system. It cast a lugubrious shadow over all of his undertakings--he found little joy and less love in life. It found its way onto his canvases, both directly--the grinning death's head--and indirectly. It found expression in his portrayals of sowers and reapers, in his representations of trees--especially the highly symbolic treatments of cypresses--in the menacing crows hovering over storm-darkened fields of wheat, and finally in the images of Christ, suffering and dead, held in the embrace of a loving and grieving mother. If death was a bottomless pit that haunted him with its terrors, it was also a siren song that drew him ever closer to his destiny, ever closer to the edge of the pit. The power of that attraction lies in his identification with the dead Vincent whose place he had taken and whose name he bore. It was through that identification, and through the passageway of suffering and death that he would surcease in the arms of a loving and accepting mother whose warm embrace he had sought throughout his odyssey, but in vain. It was to be gained only in and through death. It was only through death that he would find rest from his pain and would gain the heavenly reward of his suffering in eternal love and bliss.

  1. 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.

  2. Shapes of rotating nonsingular black hole shadows

    CERN Document Server

    Amir, Muhammed

    2016-01-01

    It is a belief that singularities are creation of general relativity and hence in the absence of a quantum gravity, models of nonsingular black hole have received significant attention. We study the shadow (apparent shape), an optical appearance because of its strong gravitational field, cast by a nonsingular black hole which is characterized by three parameters, i.e., mass ($M$), spin ($a$) and a deviation parameter ($k$). The nonsingular black hole, under consideration, is a generalization of the Kerr black hole can be recognized asymptotically ($r>>k, k>0$) explicitly as the Kerr\\(-\\)Newman black hole, and in the limit $k \\rightarrow 0$ as the Kerr black hole. It turns out that the shadow of a nonsingular black hole is a dark zone covered by deformed circle. Interestingly, it is seen that the shadow of a black hole is affected due to the parameter $k$. Indeed, for a given $a$, the size of a shadow reduces as the parameter $k$ increases and the shadow becomes more distorted as we increase the value of the p...

  3. Gluon Shadowing in DIS off Nuclei

    CERN Document Server

    Kopeliovich, B Z; Potashnikova, I K; Schmidt, I

    2008-01-01

    Within a light-cone quantum-chromodynamics dipole formalism based on the Green function technique, we study nuclear shadowing in deep-inelastic scattering at small Bjorken xB 0.0001, when a variation of the transverse size of the \\bar{q}q Fock component must be taken into account. The eikonal approximation, used so far in most other models, can be applied only at high energies, when xB < 0.0001 and the transverse size of the \\bar{q}q Fock component is "frozen" during propagation through the nuclear matter. At xB < 0.01 we find quite a large contribution of gluon suppression to nuclear shadowing, as a shadowing correction for the higher Fock states containing gluons. Numerical results for nuclear shadowing are compared with the available data from the E665 and NMC collaborations. Nuclear shadowing is also predicted at very small xB corresponding to LHC kinematical range. Finally the model predictions are compared and discussed with the results obtained from other models.

  4. Shadows alter facial expressions of Noh masks.

    Science.gov (United States)

    Kawai, Nobuyuki; Miyata, Hiromitsu; Nishimura, Ritsuko; Okanoya, Kazuo

    2013-01-01

    A Noh mask, worn by expert actors during performance on the Japanese traditional Noh drama, conveys various emotional expressions despite its fixed physical properties. How does the mask change its expressions? Shadows change subtly during the actual Noh drama, which plays a key role in creating elusive artistic enchantment. We here describe evidence from two experiments regarding how attached shadows of the Noh masks influence the observers' recognition of the emotional expressions. In Experiment 1, neutral-faced Noh masks having the attached shadows of the happy/sad masks were recognized as bearing happy/sad expressions, respectively. This was true for all four types of masks each of which represented a character differing in sex and age, even though the original characteristics of the masks also greatly influenced the evaluation of emotions. Experiment 2 further revealed that frontal Noh mask images having shadows of upward/downward tilted masks were evaluated as sad/happy, respectively. This was consistent with outcomes from preceding studies using actually tilted Noh mask images. Results from the two experiments concur that purely manipulating attached shadows of the different types of Noh masks significantly alters the emotion recognition. These findings go in line with the mysterious facial expressions observed in Western paintings, such as the elusive qualities of Mona Lisa's smile. They also agree with the aesthetic principle of Japanese traditional art "yugen (profound grace and subtlety)", which highly appreciates subtle emotional expressions in the darkness.

  5. Shadows alter facial expressions of Noh masks.

    Directory of Open Access Journals (Sweden)

    Nobuyuki Kawai

    Full Text Available BACKGROUND: A Noh mask, worn by expert actors during performance on the Japanese traditional Noh drama, conveys various emotional expressions despite its fixed physical properties. How does the mask change its expressions? Shadows change subtly during the actual Noh drama, which plays a key role in creating elusive artistic enchantment. We here describe evidence from two experiments regarding how attached shadows of the Noh masks influence the observers' recognition of the emotional expressions. METHODOLOGY/PRINCIPAL FINDINGS: In Experiment 1, neutral-faced Noh masks having the attached shadows of the happy/sad masks were recognized as bearing happy/sad expressions, respectively. This was true for all four types of masks each of which represented a character differing in sex and age, even though the original characteristics of the masks also greatly influenced the evaluation of emotions. Experiment 2 further revealed that frontal Noh mask images having shadows of upward/downward tilted masks were evaluated as sad/happy, respectively. This was consistent with outcomes from preceding studies using actually tilted Noh mask images. CONCLUSIONS/SIGNIFICANCE: Results from the two experiments concur that purely manipulating attached shadows of the different types of Noh masks significantly alters the emotion recognition. These findings go in line with the mysterious facial expressions observed in Western paintings, such as the elusive qualities of Mona Lisa's smile. They also agree with the aesthetic principle of Japanese traditional art "yugen (profound grace and subtlety", which highly appreciates subtle emotional expressions in the darkness.

  6. Shadow Economy in Slovenia: The Labour Approach

    Directory of Open Access Journals (Sweden)

    Bojan Nastav

    2007-06-01

    Full Text Available The all-around notorious shadow economy phenomenon is subject to constant reshaping, regarding both time and place, which results in a somewhat unclear definition. We use the following definition: all productive activities, whose output is legal, but is deliberately concealed from the authorities, usually for gaining financial benefits. Different methods of quantifying the size of the shadow economy have been developed. We focus on the labour approach, with Slovenia as the case study during the last decade. The importance of such an analysis lies in the ambiguous effects of the shadow economy and their policy implications. We found that the shadow economy that relates only to the unemployment discrepancies in Slovenia amounts on average to around 6 percent of the official economy, and tends to slightly decline over the most recent years. On the other hand, employment discrepancy and more detailed activity-level results give much higher values and even an increase in the shadow economy: on average around 20 percent in the studied period.

  7. Interactive removal and ground truth for difficult shadow scenes.

    Science.gov (United States)

    Gong, Han; Cosker, Darren

    2016-09-01

    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 estimation of nonuniform shadow illumination changes, resulting in accurate and robust removal. Another major contribution of this work is the first validated and multiscene category ground truth for shadow removal algorithms. This data set containing 186 images eliminates inconsistencies between shadow and shadow-free images and provides a range of different shadow types such as soft, textured, colored, and broken shadow. Using this data, the most thorough comparison of state-of-the-art shadow removal methods to date is performed, showing our proposed algorithm to outperform the state of the art across several measures and shadow categories. To complement our data set, an online shadow removal benchmark website is also presented to encourage future open comparisons in this challenging field of research.

  8. Interactive removal and ground truth for difficult shadow scenes

    Science.gov (United States)

    Gong, Han; Cosker, Darren

    2016-09-01

    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 estimation of non-uniform shadow illumination changes, resulting in accurate and robust removal. Another major contribution of this work is the first validated and multi-scene category ground truth for shadow removal algorithms. This data set containing 186 images eliminates inconsistencies between shadow and shadow-free images and provides a range of different shadow types such as soft, textured, colored and broken shadow. Using this data, the most thorough comparison of state-of-the-art shadow removal methods to date is performed, showing our proposed new algorithm to outperform the state-of-the-art across several measures and shadow category. To complement our dataset, an online shadow removal benchmark website is also presented to encourage future open comparisons in this challenging field of research.

  9. 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

  10. Shadow detection and removal based on the saliency map

    Science.gov (United States)

    Fang, Zhiwen; Cao, Zhiguo; Deng, Chunhua; Yan, Ruicheng; Qin, Yueming

    2013-10-01

    The detection of shadow is the first step to reduce the imaging effect that is caused by the interactions of the light source with surfaces, and then shadow removal can recover the vein information from the dark region. In this paper, we have presented a new method to detect the shadow in a single nature image with the saliency map and to remove the shadow. Firstly, RGB image is transferred to 2D module in order to improve the blue component. Secondly, saliency map of blue component is extracted via graph-based manifold ranking. Then the edge of the shadow can be detected in order to recover the transitional region between the shadow and non-shadow region. Finally, shadow is compensated by enhancing the image in RGB space. Experimental results show the effectiveness of the proposed method.

  11. Chromatic Shadow Detection and Tracking for Moving Foreground Segmentation

    DEFF Research Database (Denmark)

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

    2015-01-01

    Advanced segmentation techniques in the surveillance domain deal with shadows to avoid distortions when detecting moving objects. Most approaches for shadow detection are still typically restricted to penumbra shadows and cannot cope well with umbra shadows. Consequently, umbra shadow regions...... are usually detected as part of moving objects, thus affecting the performance of the final detection. In this paper we address the detection of both penumbra and umbra shadow regions. First, a novel bottom-up approach is presented based on gradient and colour models, which successfully discriminates between...... chromatic moving cast shadow regions and those regions detected as moving objects. In essence, those regions corresponding to potential shadows are detected based on edge partitioning and colour statistics. Subsequently (i) temporal similarities between textures and (ii) spatial similarities between...

  12. 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....... Consequently, umbra shadows are usually detected as part of moving objects. In this paper we present a novel technique based on gradient and colour models for separating chromatic moving cast shadows from detected moving objects. Firstly, both a chromatic invariant colour cone model and an invariant gradient...... model are built to perform automatic segmentation while detecting potential shadows. In a second step, regions corresponding to potential shadows are grouped by considering "a bluish effect" and an edge partitioning. Lastly, (i) temporal similarities between textures and (ii) spatial similarities...

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

    Science.gov (United States)

    2017-01-01

    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. PMID:28296912

  14. 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…

  15. 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 Nie...

  16. Multithreshold progressive image sharing with compact shadows

    Science.gov (United States)

    Chen, Lee Shu-Teng; Lin, Ja-Chen

    2010-01-01

    We propose a multithreshold progressive reconstruction method. The image is encoded three times using Joint Photographic Experts Group (JPEG): first with a low-quality factor, then with a medium-quality factor, and last with a high-quality factor. Huffman coding is employed to encode the difference between the important image and the high-quality JPEG decompressed image. The three JPEG codes and the Huffman code are shared, respectively, according to four prespecified thresholds. The n-generated equally important shadows can be stored or transmitted using n channels in parallel. Cooperation among these generated shadows can progressively reconstruct the important image. The reconstructed image is loss-free when the number of collected shadows reaches the largest threshold. Each shadow is very compact and so can be hidden successfully in the JPEG codes of cover images to reduce the probability of being attacked when transmitted in an unfriendly environment. Comparisons with other image sharing methods are made. The contributions, such as easiness to apply to scalable Moving Picture Experts Group (MPEG) video transmission or resistance to differential attack, are also included.

  17. Robust road detection in shadow conditions

    Science.gov (United States)

    Lu, Kaiyue; Xia, Siyu; Zhang, Junkang; Qin, A. Kai

    2016-07-01

    Image-based road detection is a vital task for many real-world applications, such as autonomous driving and obstacle detection. We propose a method for segmenting road regions from a single image based on horizon line estimation and clustering technology. The key idea is to leverage normalized cross correlation to search for the line separating the road image. Additionally, we divide the lower part of the road image into several identical parts horizontally and utilize a density-peak clustering algorithm in terms of gray and HSV value of each pixel. Clustering results are further labeled as road and nonroad based on the assumption that two adjacent horizontal parts share similar clustering size and average gray value. For road images with shadows, we also propose a new shadow-free space derived from HSV space. By calculating maximum entropy and reconstructing images, we show that shadows are eliminated to achieve better road detection. Experimental results on four datasets and shadow images demonstrate the effectiveness and robustness of our method.

  18. 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.

  19. THE SHADOW ECONOMY AS AN ECONOMIC CATEGORY AND OBJECT EVALUATION

    Directory of Open Access Journals (Sweden)

    А. Khodzhaian

    2014-12-01

    Full Text Available The article considers the existing scientific approaches to the formulation of the concept of nature and the structural elements of the shadow economy. Contains definitions of the shadow economy as an object of evaluation. Disclosed manifestations shadow relations in the context of the institutional sectors. Characterized by methods of assessment of the informal sector in terms of their object of study.

  20. Shadows Alter Facial Expressions of Noh Masks

    Science.gov (United States)

    Kawai, Nobuyuki; Miyata, Hiromitsu; Nishimura, Ritsuko; Okanoya, Kazuo

    2013-01-01

    Background A Noh mask, worn by expert actors during performance on the Japanese traditional Noh drama, conveys various emotional expressions despite its fixed physical properties. How does the mask change its expressions? Shadows change subtly during the actual Noh drama, which plays a key role in creating elusive artistic enchantment. We here describe evidence from two experiments regarding how attached shadows of the Noh masks influence the observers’ recognition of the emotional expressions. Methodology/Principal Findings In Experiment 1, neutral-faced Noh masks having the attached shadows of the happy/sad masks were recognized as bearing happy/sad expressions, respectively. This was true for all four types of masks each of which represented a character differing in sex and age, even though the original characteristics of the masks also greatly influenced the evaluation of emotions. Experiment 2 further revealed that frontal Noh mask images having shadows of upward/downward tilted masks were evaluated as sad/happy, respectively. This was consistent with outcomes from preceding studies using actually tilted Noh mask images. Conclusions/Significance Results from the two experiments concur that purely manipulating attached shadows of the different types of Noh masks significantly alters the emotion recognition. These findings go in line with the mysterious facial expressions observed in Western paintings, such as the elusive qualities of Mona Lisa’s smile. They also agree with the aesthetic principle of Japanese traditional art “yugen (profound grace and subtlety)”, which highly appreciates subtle emotional expressions in the darkness. PMID:23940748

  1. Dense surface reconstruction with shadows in MIS.

    Science.gov (United States)

    Lin, Bingxiong; Sun, Yu; Qian, Xiaoning

    2013-09-01

    Three-dimensional reconstruction of internal organ surfaces provides useful information for better control and guidance of the operations of surgical tools for minimally invasive surgery (MIS). The current reconstruction techniques using stereo cameras are still challenging due to the difficulties in correspondence matching in MIS, since there is very limited texture but significant specular reflection on organ surfaces. This paper proposes a new approach to overcome the problem by introducing weakly structured light actively casting surgical tool shadows on organ surfaces. The contribution of this paper is twofold: first, we propose a robust approach to extract shadow edges from a sequence of shadowed images; second, we develop a novel field surface interpolation (FSI) approach to obtain an accurate and dense disparity map. Our approach does not rely on texture information and is able to reconstruct accurate 3-D information by exploiting shadows from surgical tools. One advantage is that the point correspondences are directly calculated and no explicit stereo matching is required, which ensures the efficiency of the method. Another advantage is the minimum hardware requirement because only stereo cameras and a separated single-point light source are required. We evaluated the proposed approach using both phantom models and ex vivo images. Based on the experimental results, we achieved the precision of the recovered 3-D surfaces within 0.7 mm for phantom models and 1.2 mm for ex vivo images. The comparison of disparity maps indicates that with the addition of shadows, the proposed method significantly outperforms the state-of-the-art stereo algorithms for MIS.

  2. Connecting the shadows: probing inner disk geometries using shadows in transitional disks

    Science.gov (United States)

    Min, M.; Stolker, T.; Dominik, C.; Benisty, M.

    2017-08-01

    Aims: Shadows in transitional disks are generally interpreted as signs of a misaligned inner disk. This disk is usually beyond the reach of current day high contrast imaging facilities. However, the location and morphology of the shadow features allow us to reconstruct the inner disk geometry. Methods: We derive analytic equations of the locations of the shadow features as a function of the orientation of the inner and outer disk and the height of the outer disk wall. In contrast to previous claims in the literature, we show that the position angle of the line connecting the shadows cannot be directly related to the position angle of the inner disk. Results: We show how the analytic framework derived here can be applied to transitional disks with shadow features. We use estimates of the outer disk height to put constraints on the inner disk orientation. In contrast with the results from Long et al. (2017, ApJ, 838, 62), we derive that for the disk surrounding HD 100453 the analytic estimates and interferometric observations result in a consistent picture of the orientation of the inner disk. Conclusions: The elegant consistency in our analytic framework between observation and theory strongly support both the interpretation of the shadow features as coming from a misaligned inner disk as well as the diagnostic value of near infrared interferometry for inner disk geometry.

  3. When a giant falls, dwarfs have no shadow

    Directory of Open Access Journals (Sweden)

    Juan Gérvas

    2011-06-01

    Full Text Available It is said that in times of war old people bury young men. As we live in times of peace, and we are old, youngsters will need to bury us. It is said that we become good people after we die. But some of us were good before dying. They were good, generous and honored, wise and tender, effectively human. Some who passed away used to give us a cozy and protective shadow, and their absence leaves us unsheltered, alone with danger. A long time ago, one of our children asked to us: “When an old wise man dies, where does his knowledge and experience go to?”. We were not quite sure about the answer. “When this person has family and friends, they all learn from him. Thus, there will be a lot in their hearts and minds, and his/her kindness, culture, wisdom and accomplishments will be a part of memory, which will pass from generation to generation; it has been this way since the beginning of humanity. If this person diffused activities and work, whether written or illustrated, these will be his/her own words, and this person may be seen and revisited from time to time. Sometimes, words remain and we do not even know to whom they belong to, like Gilgamesh and his poem. Other times, authorship is neglected, even if we know who the author is, like Aristotle. And, other times, memory is alive and recent, like the work of Albert Einstein”. At that time, we did not think about it – but we do now – when a giant dies, we are left without a shadow. Barbara Starfield passed away, a giant in Primary Health Care (PHC, and her protective shadow abandoned us. She was a wise elderly woman, even though she looked young and looked like a student. Barbara Starfield had friends and family members who are capable of passing on her legacy of knowledge, kindness, culture, and wisdom, including many of her deeds and anecdotes. Barbara Starfield also leaves multiple registers, articles, books and presentations, which will serve as a path for others to go further. She

  4. 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

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

    CERN Document Server

    Allison, W W M; Ayres, D S; Barrett, W L; Bode, C; Border, P M; Brooks, C B; Cobb, J H; Cotton, R J; Courant, H; Demuth, D M; Fields, T H; Gallagher, H R; García-García, C; Goodman, M C; Gran, R; Joffe-Minor, T M; Kafka, T; Kasahara, S M; Leeson, W; Lichtfield, P J; Longley, N P; Mann, W A; Marshak, M L; Milburn, R H; Miller, W H; Mualem, L M; Napier, A; Oliver, W P; Pearce, G F; Peterson, E A; Petyt, D A; Price, L E; Ruddick, K; Sánchez, M; Schneps, J; Schub, M H; Seidlein, R; Stassinakis, A; Thron, J L; Vasilev, V; Villaume, G; Wakely, S P; West, N; Wall, D

    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 observed during the years 1995 to 1998.

  6. Moving Shadow Detection and Removal for Traffic Sequences

    Institute of Scientific and Technical Information of China (English)

    Mei Xiao; Chong-Zhao Han; Lei Zhang

    2007-01-01

    Segmentation of moving objects in a video sequence is a basic task for application of computer vision. However, shadows extracted along with the objects can result in large errors in object localization and recognition. In this paper, we propose a method of moving shadow detection based on edge information, which can effectively detect the cast shadow of a moving vehicle in a traffic scene. Having confirmed shadows existing in a figure, we execute the shadow removal algorithm proposed in this paper to segment the shadow from the foreground. The shadow eliminating algorithm removes the boundary of the cast shadow and preserves object edges firstly; secondly, it reconstructs coarse object shapes based on the edge information of objects; and finally, it extracts the cast shadow by subtracting the moving object from the change detection mask and performs further processing. The proposed method has been further tested on images taken under different shadow orientations, vehicle colors and vehicle sizes, and the results have revealed that shadows can be successfully eliminated and thus good video segmentation can be obtained.

  7. Shadows of Kerr black holes with and without scalar hair

    CERN Document Server

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

    2016-01-01

    For an observer, the Black Hole (BH) shadow is the BH's apparent image in the sky due to the gravitational lensing of nearby radiation, emitted by an external source. A recent class of solutions dubbed Kerr BHs with scalar hair possess smaller shadows than the corresponding Kerr BHs and, under some conditions, novel exotic shadow shapes can arise. Thus, these hairy BHs could potentially provide new shadow templates for future experiments such as the Event Horizon Telescope. In order to obtain the shadows, the backward ray-tracing algorithm is briefly introduced, followed by numerical examples of shadows of Kerr BHs with scalar hair contrasting with the Kerr analogues. Additionally, an analytical solution for the Kerr shadow is derived in closed form for a ZAMO observer at an arbitrary position.

  8. Shadows of Kerr black holes with and without scalar hair

    Science.gov (United States)

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

    2016-06-01

    For an observer, the Black Hole (BH) shadow is the BHs apparent image in the sky due to the gravitational lensing of nearby radiation, emitted by an external source. A recent class of solutions dubbed Kerr BHs with scalar hair possess smaller shadows than the corresponding Kerr BHs and, under some conditions, novel exotic shadow shapes can arise. Thus, these hairy BHs could potentially provide new shadow templates for future experiments such as the Event Horizon Telescope. In order to obtain the shadows, the backward ray-tracing algorithm is briefly introduced, followed by numerical examples of shadows of Kerr BHs with scalar hair contrasting with the Kerr analogues. Additionally, an analytical solution for the Kerr shadow is derived in closed form for a ZAMO observer at an arbitrary position.

  9. Are Shadows Only Coarsely Processed? Exploring Depth Discrimination with Cast Shadow Cue Conflicts Across Spatial Frequency

    Directory of Open Access Journals (Sweden)

    P.G Lovell

    2014-08-01

    Full Text Available Shape-from-shading is a ubiquitous cue informing object identification and depth judgements. Cast-shadows contribute towards these judgements (see Mammassian, Knill and Kersten, 1998. A number of studies have reported that search-times for inconsistent shadows vary according to whether the scene is presented as-if illuminated from above or below. Though the direction of these inhomogeneities is sometimes contested (see Rensink and Cavanagh, 2004 and Lovell et al, 2009. Lovell et. al. posit that the processing of shadows is handled by coarse-scale processes, but only in light-from-above presentations. The current study explores depth discrimination judgements informed by cast shadows. We create stimuli featuring a pair of floating discs, casting shadows onto a fronto-parallel surface. Participants were asked to identify the disc protruding the most towards them. One disc featured a cast-shadow with a cue-conflict, where low and high spatial-frequency components conveyed different depth information. This allowed us to estimate the weight assigned to the different cues when depth discrimination judgements were made. Firstly, we find that depth judgements consistently reflected the coarse-scale cues, fine-scale cues were largely ignored. Secondly, we found only small differences in the cue weightings for stimuli presented as-if light were above or below. The latter result is perplexing as previous studies have shown a difference between light-from-above and below conditions. We speculate that this difference reflects the task undertaken, i.e. discriminating depths rather than searching for odd shadows.

  10. Nuclear Shadowing at Small Values of X.

    Science.gov (United States)

    Qiu, Jian-Wei

    The nuclear parton distributions are given in a model where the nucleus is viewed as a collection of uncorrelated nucleons. Using these distributions, we determine nuclear shadowing at small values of x. We find that the effect of nuclear shadowing goes away very slowly when Q^2 increases. Our results are consistent with the experiment of Goodman et al. Using these distributions, we also determine the A-dependence of hadronic charm productions. Defining total cross sections of hadronic charm production in pA and pp collisions as sigma_{rm pAto c | c} = A^alpha sigma_{rm ppto c| c}, we find that alpha is bigger than 0.96 for all physically existing nuclei at present collider energies.

  11. Numerical shadow and geometry of quantum states

    Energy Technology Data Exchange (ETDEWEB)

    Dunkl, Charles F [Department of Mathematics, University of Virginia, Charlottesville, VA 22904-4137 (United States); Gawron, Piotr; Miszczak, Jaroslaw A; Puchala, Zbigniew [Institute of Theoretical and Applied Informatics, Polish Academy of Sciences, Baltycka 5, 44-100 Gliwice (Poland); Holbrook, John A [Department of Mathematics and Statistics, University of Guelph, Guelph, Ontario N1G 2W1 (Canada); Zyczkowski, Karol, E-mail: cfd5z@virginia.edu, E-mail: gawron@iitis.pl, E-mail: jholbroo@uoguelph.ca, E-mail: miszczak@iitis.pl, E-mail: z.puchala@iitis.pl, E-mail: karol@tatry.if.uj.edu.pl [Institute of Physics, Jagiellonian University, Reymonta 4, 30-059 Krakow (Poland)

    2011-08-19

    The totality of normalized density matrices of dimension N forms a convex set Q{sub N} in R{sup N2-1}. Working with the flat geometry induced by the Hilbert-Schmidt distance, we consider images of orthogonal projections of Q{sub N} onto a two-plane and show that they are similar to the numerical ranges of matrices of dimension N. For a matrix A of dimension N, one defines its numerical shadow as a probability distribution supported on its numerical range W(A), induced by the unitarily invariant Fubini-Study measure on the complex projective manifold CP{sup N-1}. We define generalized, mixed-state shadows of A and demonstrate their usefulness to analyse the structure of the set of quantum states and unitary dynamics therein.

  12. Numerical shadow and geometry of quantum states

    CERN Document Server

    Dunkl, Charles F; Holbrook, John A; Miszczak, Jarosław A; Puchała, Zbigniew; Życzkowski, Karol

    2011-01-01

    The totality of normalised density matrices of order N forms a convex set Q_N in R^(N^2-1). Working with the flat geometry induced by the Hilbert-Schmidt distance we consider images of orthogonal projections of Q_N onto a two-plane and show that they are similar to the numerical ranges of matrices of order N. For a matrix A of a order N one defines its numerical shadow as a probability distribution supported on its numerical range W(A), induced by the unitarily invariant Fubini-Study measure on the complex projective manifold CP^(N-1). We define generalized, mixed-states shadows of A and demonstrate their usefulness to analyse the structure of the set of quantum states and unitary dynamics therein.

  13. Scaling and shadowing effects in ballistic aggregation

    Science.gov (United States)

    Joag, P. S.; Limaye, A. V.; Amritkar, R. E.

    1987-10-01

    We have studied the scaling and shadowing properties of two-dimensional off-lattice ballistic aggregation on a seed. The computer simulations show that the limiting semivertical cone angle is about 15.5°. The density as a function of distance from the seed tends to a constant value showing a basic two-dimensional nature of the aggregates and has a correction with a metadimension of about 0.56. The density as a function of angle near the edges of the cone is found to obey a scaling relation similar to the on-lattice case. The probabilities for the fingers of different lengths which shadow the particle near the edge are determined in the computer experiment and also determined analytically.

  14. Initial conditions from the shadowed Glauber model

    CERN Document Server

    Chatterjee, Sandeep; Ghosh, Snigdha; Hasanujjaman, Md; Alam, Jane; Sarkar, Sourav

    2015-01-01

    The two component Monte-Carlo Glauber model predicts a knee-like structure in the centrality dependence of elliptic flow $v_2$ in Uranium+Uranium collisions at $\\sqrt{s_{\\rm NN}}=193$ GeV. It also produces a strong anti-correlation between $v_2$ and $dN_{ch}/dy$ in the case of top ZDC events. However, none of these features have been observed in data. We address these discrepancies by including the effect of nucleon shadowing to the two component Monte-Carlo Glauber model. Apart from addressing successfully the above issues, we find that the nucleon shadow suppresses the event by event fluctuation of various quantities, e.g. $\\varepsilon_2$ which is in accordance with expectation from the dynamical models of initial condition based on gluon saturation physics.

  15. 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...

  16. Shadow price in the power utility case

    OpenAIRE

    Attila Herczegh; Vilmos Prokaj

    2011-01-01

    We consider the problem of maximizing expected power utility from consumption over an infinite horizon in the Black–Scholes model with proportional transaction costs, as studied in Shreve and Soner [ Ann. Appl. Probab. 4 (1994) 609–692]. ¶ Similar to Kallsen and Muhle-Karbe [ Ann. Appl. Probab. 20 (2010) 1341–1358], we derive a shadow price, that is, a frictionless price process with values in the bid-ask spread which leads to the same optimal policy.

  17. "Shadow Banking: Policy Challenges for Central Banks"

    OpenAIRE

    Moe, Thorvald Grung

    2014-01-01

    Central banks responded with exceptional liquidity support during the financial crisis to prevent a systemic meltdown. They broadened their tool kit and extended liquidity support to nonbanks and key financial markets. Many want central banks to embrace this expanded role as "market maker of last resort" going forward. This would provide a liquidity backstop for systemically important markets and the shadow banking system that is deeply integrated with these markets. But how much liquidity su...

  18. Black Hole Shadows and VSOP-2

    Science.gov (United States)

    Takahashi, R.

    2009-08-01

    The radio images in the galactic center with micro-arcsecond resolution will be obtained by the radio interferometer VSOP-2. The apparent sizes of the direct images of the black holes in the nearby massive galaxies such as M87 and Sgr A* also have micro-arcsecond scales, and such black holes will be seen as the shadows in the luminous accreting matter around the black holes. At 43 GHz where VSOP-2 has the highest spatial resolution (38 μarcseconds), the observed images of Sgr A* are smeared out by the interstellar scattering. Therefore, the shadow of Sgr A* will not be resolved at this frequency. In the case of M87, the observed values of the black hole mass and the distance are not precisely determined. The possible minimum angular size of the highest spatial resolution of VSOP-2 corresponds to 12.5 GMBH/c^2 which is smaller than the shadow size of the slowly rotating black hole in the accretion flow with the inner edge of the marginally stable orbit. On the other hand, the possible maximum angular size of the highest spatial resolution of VSOP-2 corresponds to 38.1 GMBH/c^2. In this case, for any value of the black hole spin and the observed inclination angle, the size of the black hole shadow is smaller than the highest spatial resolution of VSOP-2. On the other hand, the observed energy spectrum of the accretion flow in M87 is consistent with the radiatively inefficient accretion flow where the electron temperature is higher than the detection temperature of VSOP-2. This means that the photons from the accretion flow around the black hole in M87 can be detected by VSOP-2. Other related issues are also discussed.

  19. The shadow of a naked singularity

    CERN Document Server

    Ortiz, Néstor; Zannias, Thomas

    2015-01-01

    We analyze the redshift suffered by photons originating from an external source, traversing a collapsing dust cloud and finally received by an asymptotic observer. In addition, we study the shadow that the collapsing cloud casts on the sky of the asymptotic observer. We find that the resulting redshift and properties of the shadow depend crucially on whether the final outcome of the complete gravitational collapse is a black hole or a naked singularity. In the black hole case, the shadow is due to the high redshift acquired by the photons as they approach the event horizon, implying that their energy is gradually redshifted towards zero within a few crossing times associated with the event horizon radius. In contrast to this, a naked singularity not only absorbs photons originating from the source, but it also emits infinitely redshifted photons with and without angular momenta. This emission introduces an abrupt cut-off in the frequency shift of the photons detected in directions close to the radial one, and...

  20. Aftershocks halted by static stress shadows

    Science.gov (United States)

    Toda, Shinji; Stein, Ross S.; Beroza, Gregory C.; Marsan, David

    2012-06-01

    Earthquakes impart static and dynamic stress changes to the surrounding crust. Sudden fault slip causes small but permanent--static--stress changes, and passing seismic waves cause large, but brief and oscillatory--dynamic--stress changes. Because both static and dynamic stresses can trigger earthquakes within several rupture dimensions of a mainshock, it has proven difficult to disentangle their contributions to the triggering process. However, only dynamic stress can trigger earthquakes far from the source, and only static stress can create stress shadows, where the stress and thus the seismicity rate in the shadow area drops following an earthquake. Here we calculate the stress imparted by the magnitude 6.1 Joshua Tree and nearby magnitude 7.3 Landers earthquakes that occurred in California in April and June 1992, respectively, and measure seismicity through time. We show that, where the aftershock zone of the first earthquake was subjected to a static stress increase from the second, the seismicity rate jumped. In contrast, where the aftershock zone of the first earthquake fell under the stress shadow of the second and static stress dropped, seismicity shut down. The arrest of seismicity implies that static stress is a requisite element of spatial clustering of large earthquakes and should be a constituent of hazard assessment.

  1. PCAC and shadowing of low energy neutrinos

    Science.gov (United States)

    Kopeliovich, B. Z.

    2005-02-01

    The Adler relation between reactions initiated by neutrinos and pions is easy to misinterpret as a manifestation of the pion pole dominance. An axial current, however, cannot fluctuate into a pion, but only to heavy axial-vector states, since the lepton current is transverse. This is the miracle of the PCAC hypothesis which dictates a specific conspiracy between the heavy fluctuations, so that all together they mock the pion pole. Indeed, the observed Q2 dependence of the axial form factor is controlled by the effective mass m˜1 GeV, rather than the pion mass. On the contrary, the onset of nuclear shadowing is governed by the small pion mass, rather than by the large axial mass scale. This is in variance with the conventional wisdom which equates the fluctuation lifetime and the coherence time. For the case of axial current they are different by almost two orders of magnitude. As a result, neutrino interactions are shadowed at very low energies of few hundred MeV, while energy of about 10 GeV is needed to access nuclear shadowing for the vector current. On the contrary to naive expectations, nuclear absorption enhances, rather than suppresses the cross section of coherent neutrino-production of pions which is the strongest channel (half of the total cross section) in the black disc limit.

  2. Perception of shadows in children with autism spectrum disorders.

    Directory of Open Access Journals (Sweden)

    Cristina Becchio

    Full Text Available BACKGROUND: Cast shadows in visual scenes can have profound effects on visual perception. Much as they are informative, they also constitute noise as they are salient features of the visual scene potentially interfering with the processing of other features. Here we asked i whether individuals with autism can exploit the information conveyed by cast shadows; ii whether they are especially sensitive to noise aspects of shadows. METHODOLOGY/PRINCIPAL FINDINGS: Twenty high-functioning children with autism and twenty typically developing children were asked to recognize familiar objects while the presence, position, and shape of the cast shadow were systematically manipulated. Analysis of vocal reaction time revealed that whereas typically developing children used information from cast shadows to improve object recognition, in autistic children the presence of cast shadows--either congruent or incongruent--interfered with object recognition. Critically, vocal reaction times were faster when the object was presented without a cast shadow. CONCLUSIONS/SIGNIFICANCE: We conclude that shadow-processing mechanisms are abnormal in autism. As a result, processing shadows becomes costly and cast shadows interfere rather than help object recognition.

  3. 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.

  4. Direct 3D printed shadow mask on Silicon

    Science.gov (United States)

    Rahiminejad, S.; Köhler, E.; Enoksson, P.

    2016-10-01

    A 3D printed shadow mask method is presented. The 3D printer prints ABS plastic directly on the wafer, thus avoiding gaps between the wafer and the shadow mask, and deformation during the process. The wafer together with the 3D printed shadow mask was sputtered with Ti and Au. The shadow mask was released by immersion in acetone. The sputtered patches through the shadow mask were compared to the opening of the 3D printed shadow mask and the design dimensions. The patterned Au patches were larger than the printed apertures, however they were smaller than the design widths. The mask was printed in 4 min, the cost is less than one euro cent, and the process is a low temperature process suitable for temperature sensitive components.

  5. 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.

  6. Shadow of a charged rotating non-commutative black hole

    Energy Technology Data Exchange (ETDEWEB)

    Sharif, M. [University of the Punjab, Department of Mathematics, Lahore (Pakistan); Pakistan Academy of Sciences, Islamabad (Pakistan); Iftikhar, Sehrish [University of the Punjab, Department of Mathematics, Lahore (Pakistan)

    2016-11-15

    This paper investigates the shadow of a charged rotating non-commutative black hole. For this purpose, we first formulate the null geodesics and study the effects of a non-commutative charge on the photon orbit. We then explore the effect of spin, angle of inclination as well as non-commutative charge on the silhouette of the shadow. It is found that shape of the shadow deviates from the circle with the decrease in the non-commutative charge. We also discuss observable quantities to study the deformation and distortion in the shadow cast by the black hole which decreases for small values of a non-commutative charge. Finally, we study the shadows in the presence of plasma. We conclude that the non-commutativity has a great impact on the black hole shadow. (orig.)

  7. 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.

  8. Shadow of a Charged Rotating Non-Commutative Black Hole

    CERN Document Server

    Sharif, M

    2016-01-01

    This paper investigates the shadow of a charged rotating non-commutative black hole. For this purpose, we first formulate the null geodesics and study the effects of non-commutative charge on the photon orbit. We then explore the effect of spin, angle of inclination as well as non-commutative charge on the silhouette of the shadow. It is found that shape of the shadow deviates from the circle with the decrease in the non-commutative charge. We also discuss observable quantities to study the deformation and distortion in the shadow cast by the black hole which decreases for small values of non-commutative charge. Finally, we study the shadows in the presence of plasma. We conclude that the non-commutativity has a great impact on the black hole shadow.

  9. A method of shadow puppet figure modeling and animation

    Institute of Scientific and Technical Information of China (English)

    Xiao-fang HUANG; Shou-qian SUN; Ke-jun ZHANG; Tian-ning XU; Jian-feng WU; Bin ZHU

    2015-01-01

    To promote the development of the intangible cultural heritage of the world, shadow play, many studies have focused on shadow puppet modeling and interaction. Most of the shadow puppet figures are still imaginary, spread by ancients, or carved and painted by shadow puppet artists, without consideration of real dimensions or the appearance of human bodies. This study proposes an algorithm to transform 3D human models to 2D puppet figures for shadow puppets, including automatic location of feature points, automatic segmentation of 3D models, automatic extraction of 2D contours, automatic clothes matching, and animation. Experiment proves that more realistic and attractive figures and animations of the shadow puppet can be generated in real time with this algorithm.

  10. Satellite images analysis for shadow detection and building height estimation

    Science.gov (United States)

    Liasis, Gregoris; Stavrou, Stavros

    2016-09-01

    Satellite images can provide valuable information about the presented urban landscape scenes to remote sensing and telecommunication applications. Obtaining information from satellite images is difficult since all the objects and their surroundings are presented with feature complexity. The shadows cast by buildings in urban scenes can be processed and used for estimating building heights. Thus, a robust and accurate building shadow detection process is important. Region-based active contour models can be used for satellite image segmentation. However, spectral heterogeneity that usually exists in satellite images and the feature similarity representing the shadow and several non-shadow regions makes building shadow detection challenging. In this work, a new automated method for delineating building shadows is proposed. Initially, spectral and spatial features of the satellite image are utilized for designing a custom filter to enhance shadows and reduce intensity heterogeneity. An effective iterative procedure using intensity differences is developed for tuning and subsequently selecting the most appropriate filter settings, able to highlight the building shadows. The response of the filter is then used for automatically estimating the radiometric property of the shadows. The customized filter and the radiometric feature are utilized to form an optimized active contour model where the contours are biased to delineate shadow regions. Post-processing morphological operations are also developed and applied for removing misleading artefacts. Finally, building heights are approximated using shadow length and the predefined or estimated solar elevation angle. Qualitative and quantitative measures are used for evaluating the performance of the proposed method for both shadow detection and building height estimation.

  11. Multi-features Based Approach for Moving Shadow Detection

    Institute of Scientific and Technical Information of China (English)

    ZHOU Ning; ZHOU Man-li; XU Yi-ping; FANG Bao-hong

    2004-01-01

    In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving visual object detection. The major novelty of the shadow suppression is the integration of several features including photometric invariant color feature, motion edge feature, and spatial feature etc. By modifying process for false shadow detected, the averaging detection rate of moving object reaches above 90% in the test of Hall-Monitor sequence.

  12. Numerical shadows: measures and densities on the numerical range

    CERN Document Server

    Dunkl, Charles F; Holbrook, John A; Puchała, Zbigniew; Zyczkowski, Karol \\

    2010-01-01

    For any operator $M$ acting on an $N$-dimensional Hilbert space $H_N$ we introduce its numerical shadow, which is a probability measure on the complex plane supported by the numerical range of $M$. The shadow of $M$ at point $z$ is defined as the probability that the inner product $(Mu,u)$ is equal to $z$, where $u$ stands for a random complex vector from $H_N$, satisfying $||u||=1$. In the case of N=2 the numerical shadow of a non-normal operator can be interpreted as a shadow of a hollow sphere projected on a plane. A similar interpretation is provided also for higher dimensions. For a hermitian $M$ its numerical shadow forms a probability distribution on the real axis which is shown to be a one dimensional $B$-spline. In the case of a normal $M$ the numerical shadow corresponds to a shadow of a transparent solid simplex in $R^{N-1}$ onto the complex plane. Numerical shadow is found explicitly for Jordan matrices $J_N$, direct sums of matrices and in all cases where the shadow is rotation invariant. Results...

  13. Shadow Detection and Compensation for Color Aerial Images

    Institute of Scientific and Technical Information of China (English)

    WANG Shugen; GUO Zejin; LI Deren

    2003-01-01

    A method for shadow detection and compensation for color aerial images is presented. It is considered that the intensity value of each image pixel is the product of illumination function and ground object reflection, and the shadowed regions on the image are mainly caused by the short of illumination, so the information compensation for the shadowed regions should concentrate on the illumination adjustment of concerned area on the basis of the analysis of whole image. The shadow detection and compensation procedure proposed by this paper consists of four steps.

  14. Field investigation of the drift shadow

    Energy Technology Data Exchange (ETDEWEB)

    Su, Grace W.; Kneafsey, Timothy J.; Ghezzehei, Teamrat A.; Marshall, Brian D.; Cook, Paul J.

    2005-09-08

    A drift shadow is an area immediately beneath an undergroundvoidthat, in theory, will be relatively drier than the surrounding rockmass. Numerical and analytical models of water flow through unsaturatedrock predict the existence of a drift shadow, but field tests confirmingits existence have yet to be performed. Proving the existence of driftshadows and understanding their hydrologic and transport characteristicscould provide a better understanding of how contaminants move in thesubsurface if released from waste emplacement drifts such as the proposednuclear waste repository at Yucca Mountain, Nevada. We describe the fieldprogram that will be used to investigate the existence of a drift shadowand the corresponding hydrological process at the Hazel-Atlas silica-sandmine located at the Black Diamond Mines Regional Preserve in Antioch,California. The location and configuration of this mine makes it anexcellent site to observe and measure drift shadow characteristics. Themine is located in a porous sandstone unit of the Domengine Formation, anapproximately 230 meter thick series of interbedded Eocene-age shales,coals, and massive-bedded sandstones. The mining method used at the minerequired the development of two parallel drifts, one above the other,driven along the strike of the mined sandstone stratum. Thisconfiguration provides the opportunity to introduce water into the rockmass in the upper drift and to observe and measure its flow around theunderlying drift. The passive and active hydrologic tests to be performedare described. In the passive method, cores will be obtained in a radialpattern around a drift and will be sectioned and analyzed for in-situwater content and chemical constituents. With the active hydrologic test,water will be introduced into the upper drift of the two parallel driftsand the flow of the water will be tracked as it passes near the bottomdrift. Tensiometers, electrical resistance probes, neutron probes, andground penetrating radar may be

  15. A Global Search for Stress Shadows

    Science.gov (United States)

    Mallman, E. P.; Parsons, T.

    2004-12-01

    For years scientists have recognized a decrease in seismicity in the regions surrounding the 1857 Fort Tejon and 1906 San Francisco earthquakes in California. This decrease in seismicity has since been correlated with calculated Coulomb stress decrease and termed a stress shadow. Earthquake hazard assessments increasingly incorporate probability perturbations resulting from calculated static stress changes. However, some researchers have questioned the existence of stress shadows when detailed studies of seismicity rates following other earthquakes failed to show correlations between calculated stress decreases and seismicity rate decreases. Regions of decreased seismicity rate are difficult to find compared with rate-increased regions; we thus look for evidence of post-seismic stress rotations, which are easier to detect, require none of the assumptions inherent to static stress calculations, and are a necessary condition for the occurrence of a stress shadow zone. A stress rotation, as determined by comparison of focal mechanisms before and after the mainshock, indicates a changed regional stress state that suppresses events of a certain mechanism and enhances events of a differing mechanism. To independently test the shadow hypothesis, we examined a global catalog of 119 M>7 earthquakes and the events within a 2-degree radius around them that were recorded by the Harvard CMT catalog. We first examined the average mechanism before and after the mainshock, and then compared this with the changes in rate of each of the mechanisms. Of the 119 mainshocks that we identified, 15 showed a rotation of average mechanism following the mainshock that was significant at the 1-sigma level relative to the observed pre-mainshock variability. Of these 15 events, only 2 did not show increases in rate across all mechanisms. That is, only 2 of the 119 show a decrease in at least one mechanism following the mainshock, and also show a significant rotation in mean mechanism. It is

  16. Glory 'in the shadow of the rainbow'

    CERN Document Server

    Ueda, M; Hussein, M S; Takigawa, N

    1999-01-01

    We show that the angular distribution of the nuclear scattering amplitude behaves like the zeroth-order Bessel function with a fixed frequency at extremely forward angles even if there exists no genuine forward glory scattering. A semiclassical interpretation of this behaviour is provided in terms of the effect of scattering in the shadow of the nuclear rainbow. We also argue that the bombarding energy dependence of the amplitude of the sum-of-difference cross section at very small angles provides a possibility to judge whether genuine forward nuclear glory scattering is taking place or not.

  17. Daisy Shadow upon the Great Gatsby

    Institute of Scientific and Technical Information of China (English)

    宋智慧

    2016-01-01

    The Great Gatsby is a significant classic in American literature. The Great Gatsby tells the love story between young Gatsby and rich Daisy. From the moment they loved each other, they cherished their pure love; to the moment Daisy hurt Gatsby twice, fragile love and crushed American dream came into their life, which indirectly led to Gatsby's death. Daisy Shadow has swallowed Gatsby's soul and destroyed his whole life. The sarcasm of the novel also makes people try best to find a good or proper ending to Gatsby, while so many possibilities lead to nothing proper.

  18. Horndeski/Galileon black hole shadows

    CERN Document Server

    Tretyakova, D A

    2016-01-01

    We examine observational signatures of the asymptotically de Sitter branch of static spherically symmetric Horndeski/Galileon solutions. Our analysis reveales that possible deviations of the photon sphere size from those of the GR Schwarzshild solution are vanishing compared to the resolution of modern radio-interferometric observations. These deviations are heavily suppressed by the bounds coming from the weak-field observation. We conclude that shadow size would not be a useful characteristic to distinguish the Horndeski/Galileon static spherically symmetric spacetimes in the foreseeable future.

  19. PCAC and Shadowing of Low Energy Neutrinos

    CERN Document Server

    Kopeliovich, B Z

    2005-01-01

    The Adler relation between reactions initiated by neutrinos and pions is easy to misinterpret as a manifestation of the pion pole dominance. An axial current, however, cannot fluctuate into a pion, but only to heavy axial-vector states, since the lepton current is transverse. This is the miracle of the PCAC hypothesis which dictates a specific conspiracy between the heavy fluctuations, so that all together they mock the pion pole. Indeed, the observed Q^2 dependence of the axial form factor is controlled by the effective mass m_A \\sim 1 GeV, rather than the pion mass. On the contrary, the onset of nuclear shadowing is governed by the small pion mass, rather than by the large axial mass scale. This is in variance with the conventional wisdom which equates the fluctuation lifetime and the coherence time. For the case of axial current they are different by almost two orders of magnitude. As a result, neutrino interactions are shadowed at very low energies of few hundred MeV, while energy of about 10 GeV is neede...

  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. Self-Attributed Body-Shadows Modulate Tactile Attention

    Science.gov (United States)

    Pavani, Francesco; Galfano, Giovanni

    2007-01-01

    Our body-shadows are special stimuli in the visual world. They often have anatomical resemblance with our own body-parts and move as our body moves, with spatio-temporal correlation. Here, we show that self-attributed body-shadows cue attention to the body-part they refer to, rather than the location they occupy. Using speeded spatial…

  2. Shadow Enhancement in Synthetic Aperture Sonar Using Fixed Focusing

    NARCIS (Netherlands)

    Groen, J.; Hansen, R.E.; Callow, H.J.; Sabel, J.C.; Sæbø, T.O.

    2009-01-01

    Abstract—A shadow cast by an object on the seafloor is important information for target recognition in synthetic aperture sonar (SAS) images. Synthetic aperture imaging causes a fundamental limitation to shadow clarity because the illuminator is moved during the data collection. This leads to a blen

  3. 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 transformation of assets and financial claims. It has also been established that fiscal and regulatory arbitrage occurs through shadow banking, and associated offshore financial activities. The article develops the argument that together these are transforming the times and spaces of modern finance, and directly...... 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...

  4. Moving Shadows, Moving Sun. Early Modem Sundials Restaging Miracles.

    Science.gov (United States)

    Mersmann, Jasmin

    2015-01-01

    Irrespective of geo- or heliocentric presuppositions, the functioning of sundials is based on the observation of moving shadows or light spots. Even though the cast shadow was often simply used to indicate the time, it could also remind the users of the ephemerality of earthly things or function as an index of planetary movements. This article examines the various ways in which early modem sundials visually interpret the moving shadow or light spot. The instruments address the shadow in inscriptions, integrate it into their design (e.g., in cruciform dials) or even manipulate its course (as in the so-called Horologium Ahaz). Both the crucifix and the Ahaz dials not only refer to astronomical miracles but actually restage them. Even though by means of the horologium it was not possible to explain the Old Testament miracle of the shadow moving backward, adepts were able to recreate it on a terrestrial scale.

  5. Synoptic and mesoscale controls on Sierra Nevada rain shadow intensity

    Science.gov (United States)

    Hatchett, B.; Kaplan, M.; Rutz, J. J.; Garner, C.

    2016-12-01

    The Sierra Nevada of California casts one of the world's greatest rain shadows with windward-leeside precipitation differences approaching an order of magnitude. Leeside rivers and terminal lakes provide critical water resources for ecosystem services and human consumptive use in this water-limited environment. They also offer important archives of paleohydroclimatic change. Understanding the drivers of rain shadow intensity represents an important step in properly evaluating how leeside hydrology will respond to projected climate change and for interpreting increasingly well spatially distributed paleoproxy evidence of past hydroclimates. Recent theoretical and modeling studies have shown rain shadow intensity to be controlled by multiscalar dynamics during storms such as the vertical structure of mountain waves, the presence of mid-level moisture, and position of the warm sector with respect to the mountain crest. Here, we provide a 35-year station-based climatology of strong and weak rain shadow events for the central Sierra Nevada during extended winter (November-April). Wetter (drier) years in leeside basins are characterized by higher (lower) fractions of lee-crest precipitation suggesting weaker (stronger) rain shadow effects during precipitation events. In general, as contributions of precipitation on the climatological top 5% of wet days increases, rain shadow intensity decreases. This suggests a key role for atmospheric rivers in weakening the rain shadow. A separate population of very dry years is found, regardless of number of dry days, when no precipitation is contributed by the climatological top 5% of wet days. These years show stronger rain shadow effects with few exceptions. Using the North American Regional Reanalysis and both surface and satellite-based remote sensing data in conjunction with the derived rain shadow climatology, we demonstrate the additional importance of atmospheric rivers, offshore and upstream mesoscale convection, and

  6. Shadowing Lemma and Chaotic Orbit Determination

    CERN Document Server

    Spoto, Federica

    2015-01-01

    Orbit determination is possible for a chaotic orbit of a dynamical system, given a finite set of observations, provided the initial conditions are at the central time. In a simple discrete model, the standard map, we tackle the problem of chaotic orbit determination when observations extend beyond the predictability horizon. If the orbit is hyperbolic, a shadowing orbit is computed by the least squares orbit determination. We test both the convergence of the orbit determination iterative procedure and the behaviour of the uncertainties as a function of the maximum number $n$ of map iterations observed. When the initial conditions belong to a chaotic orbit, the orbit determination is made impossible by numerical instability beyond a computability horizon, which can be approximately predicted by a simple formula. Moreover, the uncertainty of the results is sharply increased if a dynamical parameter is added to the initial conditions as parameter to be estimated. The uncertainty of the dynamical parameter decrea...

  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. A BRIEF ANALYSIS OF THE SHADOW ECONOMY IN EUROPE

    Directory of Open Access Journals (Sweden)

    Loredana Maftei

    2013-12-01

    Full Text Available Shadow economy affects all country around the world. European countries are affected by undeclared work, under-reporting and tax evasion. This phenomenon increases from West to East, the most affected being the Balkan area. The size of shadow economy is growing due to government actions, such as regulation and tax implementation. From a macroeconomic perspective, the economic cycle sustain the shadow economy levels. To combat this phenomenon it is necessary to adopt electronic payments, to reduce tax implementations and social contributions, to bring encouragement in cash deposits use and broaden credit cards.

  9. Shadow casted by a twisted and rotating black hole

    CERN Document Server

    Chen, Songbai

    2016-01-01

    Zhang have obtained recently a twisted rotating black hole metric, which is a vacuum solution in four-dimensional Einstein gravity. This black hole solution has a rotation parameter, but without the total angular moment. Here, we have investigated the shadow casted by a twisted rotating black hole. Our results show that the shape of the shadow of the twisted rotating black hole is a standard round disk and does not depend on the inclination angle of the observer. It means that although the twisted rotating black hole has a rotation parameter, its shadow possesses the same behaviors as the common static black hole rather than the usual Kerr-like black holes. Moreover, we find that the marginally circular orbit radius of photon is independent of the direction of photon around the black hole. The value of the marginally circular orbit radius of photon and the size of shadow increase monotonously with the rotation parameter.

  10. Designing large scale chiral metamaterials by nanosphere shadowing lithography

    Science.gov (United States)

    He, Yizhuo; Zhao, Yiping

    2016-09-01

    A scalable nanofabrication technique for chiral metamaterials is presented, which combines the dynamic shadowing growth and self-assembled nanosphere monolayers, and is also known as nanosphere shadowing lithography. We have developed two strategies based on nanosphere shadowing lithography to prepare chiral nanostructures. The first strategy is to create a quasi-three-dimensional single-layer fan-shaped chiral nanostructure on nanospheres with one plasmonic material. The second strategy is to create three-dimensional multi-layers helical nanostructures with one plasmonic material and one dielectric material. Both strategies can produce large-area chiral nanostructures with strong chiral optical response, which makes nanosphere shadowing lithography suitable for producing chiral metamaterial based devices such as an ultrathin narrow-band circular polarizer.

  11. 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.

  12. 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...... in years when they are not immediately payable due to e.g. poor investment results. When surpluses are subsequently reestablished, clearance of the shadow account balance takes priority over bonus/participation transfers to policyholders. We see such a regulatory accounting rule as a valuable option...... to equityholders and our paper develops a model in which the influence of risk charges and shadow account options on stakeholders’ value can be quantified and studied. Our numerical results show that the value of shadow account options can be significant and thus come at the risk of expropriating policyholder...

  13. 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...... in years when they are not immediately payable due to e.g. poor investment results. When surpluses are subsequently re-established, clearance of the shadow account balance takes priority over bonus/participation transfers to policyholders. We see such a regulatory accounting rule as a valuable option...... to equityholders and our paper develops a model in which the influence of risk charges and shadow account options on stakeholders' value can be quantified and studied. Our numerical results show that the value of shadow account options can be significant and thus come at the risk of expropriating policyholder...

  14. Nuclear Shadowing in the Light-Cone Dipole Approach

    CERN Document Server

    Nemchik, J

    2008-01-01

    We study nuclear shadowing at small Bjorken x < 0.01 in the color dipole approach. Such a light-cone quantum-chromodynamics formalism based on the Green function technique incorporates naturally color transparency and coherence length effects. The nuclear shadowing for the barq-q Fock component of the photon is calculated using exact numerical solution of the evolution equation for the Green function. At x < 0.01 we demonstrate that a contribution of higher Fock states containing gluons to overall nuclear shadowing becomes effective. Numerical results for nuclear shadowing are compared with available data from the E665 and NMC collaborations. Model calculations are finally tested with the results obtained from other models.

  15. The average-shadowing property and topological ergodicity for flows

    Energy Technology Data Exchange (ETDEWEB)

    Gu Rongbao [School of Finance, Nanjing University of Finance and Economics, Nanjing 210046 (China)]. E-mail: rbgu@njue.edu.cn; Guo Wenjing [School of Finance, Nanjing University of Finance and Economics, Nanjing 210046 (China)

    2005-07-01

    In this paper, the transitive property for a flow without sensitive dependence on initial conditions is studied and it is shown that a Lyapunov stable flow with the average-shadowing property on a compact metric space is topologically ergodic.

  16. Shadow Prices of Selected Agricultural Commodities – The Czech Case

    National Research Council Canada - National Science Library

    Patrik Sieber; Karina Pohlová; Ondřej Chaloupka

    2016-01-01

    ... commodities using available statistical data. More specifically, we try to analyse for which commodities secondary data sets are available from which we may deduce the estimates of shadow price ratios, then to estimate SPRs for selected...

  17. Testing General Relativity with the Shadow Size of Sgr A*

    CERN Document Server

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

    2016-01-01

    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 uas (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.

  18. Shadowing and nuclear absorption in J/. Psi. hadroproduction

    Energy Technology Data Exchange (ETDEWEB)

    Gay Ducati, M.B. (Instituto de Fisica, Universidade Federal do Rio Grande do Sul, 91500 Porto Alegre (Brazil)); Epele, L.N.; Garcia Canal, C.A. (Laboratorio de Fisica Teorica, Departamento de Fisica, Universidad Nacional de La Plata, 1900 La Plata, (Argentina))

    1989-12-15

    The hadron-nucleus J/{Psi} production is analyxed in a phenomenological picture, considering the parton recombination model. There is an evidence for a nuclear suppression effect, besides shadowing and we obtain good agreement with experimental data.

  19. A NEW METHOD OF MOVING OBJECT DETECTION AND SHADOW REMOVING

    Institute of Scientific and Technical Information of China (English)

    Hu Fuyuan; Zhang Yanning; Yao Lan; Sun Jinqiu

    2007-01-01

    This paper presents an adaptive method of objects and shadows detection in video streams.Models of background are firstly set up and adaptively updated in Hue Saturation Intensity (HSI)color space to detect motion regions. Then, detection errors are dealt with by motion continuity and velocity consistency. Finally, cast shadows are removed by the generic properties of luminance,chrominance and gradient density. Experimental results and their evaluation are presented to verify the effectiveness of this new method.

  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

    CERN Document Server

    Piller, G; Mankiewicz, L; Weise, W

    2001-01-01

    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. Observation of the Moon Shadow in Deep Underground Muon Flux

    CERN Document Server

    Cobb, J H; Allison, W W M; Alner, G J; Ayres, D S; Barrett, W L; Bode, C; Border, P M; Brooks, C B; Cotton, R J; Courant, H; Demuth, D M; Fields, T H; Gallagher, H R; García-García, C; Goodman, M C; Gran, R; Joffe-Minor, T M; Kafka, T; Kasahara, S M; Leeson, W; Lichtfield, P J; Longley, N P; Mann, W A; Milburn, R H; Miller, W H; Moon, C; Mualem, L M; Napier, A; Oliver, W P; Pearce, G F; Peterson, E A; Petyt, D A; Price, L E; Ruddick, K; Sánchez, M; Sankey, P; Schneps, J; Schub, M H; Seidlein, R; Stassinakis, A; Thron, J L; Vasilev, V; Villaume, G; Wakely, S P; West, N; Wall, D

    1999-01-01

    A shadow of the moon, with a statistical significance of $5\\sigma$, has been observed in the underground muon flux at a depth of 2090 mwe using the Soudan 2 detector. The angular resolution of the detector is well described by a Gaussian with $\\sigma \\le 0.3^{\\circ}$. The position of the shadow confirms the alignment of the detector to better than $0.15^{\\circ}$. This alignment has remained stable during 10 years of data taking from 1989 through 1998.

  3. The Pythagoreans in the light and shadows of recent research

    Directory of Open Access Journals (Sweden)

    Holger Thesleff

    1970-01-01

    Full Text Available It has been said' that "Pythagoras casts a long shadow in the history of Greek thought". Indeed, the shadow both widens and deepens spectacularly in course of time. He has not only been considered—on disputable grounds, as we shall see as the first European mystic. No other personality of the Greco–Roman world (except Christ, and perhaps Alexander the Great has been credited with such powers and all-round capacities.

  4. Observation of the moon shadow in deep underground muon flux.

    Energy Technology Data Exchange (ETDEWEB)

    Allison, W. W. M.; Alner, G. J.; Ayres, D. S.; Cobb, J. H.; Fields, T. H.; Goodman, M. C.; Joffe-Minor, T.; Marshak, M. L.; Price, L. E.; Seidlein, R.; Soudan 2 Collaboration; Thron, J. L.

    1999-06-22

    A shadow of the moon, with a statistical significance of 5{sigma}, has been observed in the underground muon flux at a depth of 2090 mwe using the Soudan 2 detector. The angular resolution of the detector is well described by a Gaussian with {sigma} {le}0.3{degree}. The position of the shadow confirms the alignment of the detector to better than 0.15{degree}. This alignment has remained stable during 10 years of data taking from 1989 through 1998.

  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. Phoenix Conductivity Probe with Shadow and Toothmark

    Science.gov (United States)

    2008-01-01

    NASA's Phoenix Mars Lander inserted the four needles of its thermal and conductivity probe into Martian soil during the 98th Martian day, or sol, of the mission and left it in place until Sol 99 (Sept. 4, 2008). The Robotic Arm Camera on Phoenix took this image on the morning of Sol 99 after the probe was lifted away from the soil. The imprint left by the insertion is visible below the probe, and a shadow showing the probe's four needles is cast on a rock to the left. The thermal and conductivity probe measures how fast heat and electricity move from one needle to an adjacent one through the soil or air between the needles. Conductivity readings can be indicators about water vapor, water ice and liquid water. The probe is part of Phoenix's Microscopy, Electrochemistry and Conductivity suite of instruments. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  7. 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.

  8. 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...

  9. Identification of Methodology of Indirect Assessment of Economy Shadowing

    Directory of Open Access Journals (Sweden)

    Avhustyn Ruslan R.

    2014-03-01

    Full Text Available The article explains the essence of the shadow economy as an objective phenomenon of socio-economic relations and its influence upon national economy security through instruments of pricing, fiscal restrictions, tax control, and banking and insurance regulation. It proves the necessity of use of the indirect method of assessment of the level of economy shadowing along with methods of direct control over the growth of shadowed economic relations, since such an approach would allow rational approach to identification of volumes and level of shadow activity. In the result of the study the article marks out varieties of indirect assessment of economy shadowing (methods of document, accounting and economic analysis, their specific features, advantages and shortcomings and results of practical use. The article reveals approaches and indicators of economic analysis that allow identification of reasons of deviations from the normal economic activity of economic subjects. It provides examples of the indirect method of assessment of the volume of shadowed economy that deal with analysis of demand on money and comparison of rates of the growth of the money supply with the volume of sight drafts with GDP.

  10. 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.

  11. 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.

  12. MACROECONOMIC DETERMINANTS OF SHADOW BANKING – EVIDENCE FROM EU COUNTRIES

    Directory of Open Access Journals (Sweden)

    TEODORA CRISTINA BARBU

    2016-12-01

    Full Text Available Shadow banking is a topical, debated issue on the agenda of national and European macro-prudential regulatory and supervisory authorities. It is generally accepted that shadow banks and the traditional banking system have some core functions in common, such as credit and maturity transformation, and the exposure to similar risks. However, the tight banking regulations and the decreasing trend recorded by interest rates in the post-crisis period create prospects for shadow banking sector growth. Against this background, the present paper aims at investigating the particular impact that shadow banking activity exerts on macroeconomic fundamentals. The analysis covers 15 European Union countries, including Romania, during the period 2008 – 2015, using quarterly data. Shadow banking system is used as a proxy by monetary funds, due to breaks in the series or unbalanced number of observations across selected countries. By employing panel regression, it was found that the shadow banking total assets’ variation is negatively influenced by the GDP growth, short term interest rates, M2/GDP ratio and the ratio of investment funds’ assets in GDP, and positively determined by stock index dynamics and long term interest rates. The findings sustain the literature’s point of view.

  13. 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...... theories and presents two overlay models. These are analyzed analytically in relation to color theory and tangibility....

  14. 基于 CUDA 的细分曲面阴影体算法%CUDA based shadow volume algorithm for subdivision surfaces

    Institute of Scientific and Technical Information of China (English)

    赵杰伊; 唐敏; 童若锋

    2012-01-01

    为了在虚拟现实、电脑游戏等图形应用中更快速生成和实时绘制细分曲面的阴影,提出采用CUDA架构的GPU阴影体生成算法.该算法采用基于CUDA的曲面细分算法,通过CUDA共享内存结构使表面细分过程更加高效.采用基于CUDA的阴影体算法产生阴影轮廓线以及拉伸出阴影体.通过基于CUDA的流式缩减算法对阴影体数组进行压缩.通过优化CUDA和OpenGL的互操作,将绘制过程从以往算法的3步减少为2步.该算法在具有CUDA硬件的标准PC上进行测试.实验结果表明,与之前的GPU的算法相比,该算法可以生成更复杂细分曲面的阴影体,阴影体数组占用显存空间降低到2%以下,并可获得高达4倍的绘制速度提升.%A new GPU based shadow volume generation algorithm based on CUDA structure was proposed for fast generation and real-time rendering of shadow of subdivision surfaces in computer games and virtual reality applications. The algorithm introduces CUDA-based surface subdivision algorithm. Generation of surface subdivisions can run faster by using shared memory structure. CUDA-based shadow volume algorithm was introduced to generate the shadow silhouette line and extrude the shadow volume. CUDA-based stream reduction algorithm was introduced to reduce the shadow volume array. An optimized interopera-tion between CUDA and OPENGL was introduced to simplify the rendering step of the algorithm from three steps to two steps. Implemented on a standard PC with CUDA hardware, experiments show that the algorithm can generate the shadow volume of more complex subdivision surfaces compared with former GPU-based ones. The algorithm needs smaller video memory for the shadow volume array to less than 2%, and the rendering performance can gain acceleration up to more than four times.

  15. 星与影的深度意象%Deep Images of Star and Shadow

    Institute of Scientific and Technical Information of China (English)

    白阳明

    2013-01-01

    Merwin is a representative poet of American “deep imagist poetry”due to the unique language and deep images of his poems.In his 2009 Pulitzer Prize work Sirius Shadow,Merwin created deep images from childhood,past things,and people and things in memory,finishing his questioning of the Sirius shadow and revealing his aesthetic pursuit of poetic dwelling.%默温因其诗歌的独特语言和深度意象而成为美国“深度意象派”代表诗人,在其2009年普利策奖作品«天狼星的影子»中,默温分别从童年、往事和记忆中的人和物塑造深度意象,完成对天狼星影子的叩问,展示其诗意栖居的审美追求。

  16. Doctoring Undercover: updating the educational tradition of shadowing

    Science.gov (United States)

    Clark, Claire D.

    2017-01-01

    ABSTRACT Background: 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. Development: 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. Implementation: 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. Future Directions: 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

  17. A separable shadow Hamiltonian hybrid Monte Carlo method.

    Science.gov (United States)

    Sweet, Christopher R; Hampton, Scott S; Skeel, Robert D; Izaguirre, Jesús A

    2009-11-07

    Hybrid Monte Carlo (HMC) is a rigorous sampling method that uses molecular dynamics (MD) as a global Monte Carlo move. The acceptance rate of HMC decays exponentially with system size. The shadow hybrid Monte Carlo (SHMC) was previously introduced to reduce this performance degradation by sampling instead from the shadow Hamiltonian defined for MD when using a symplectic integrator. SHMC's performance is limited by the need to generate momenta for the MD step from a nonseparable shadow Hamiltonian. We introduce the separable shadow Hamiltonian hybrid Monte Carlo (S2HMC) method based on a formulation of the leapfrog/Verlet integrator that corresponds to a separable shadow Hamiltonian, which allows efficient generation of momenta. S2HMC gives the acceptance rate of a fourth order integrator at the cost of a second-order integrator. Through numerical experiments we show that S2HMC consistently gives a speedup greater than two over HMC for systems with more than 4000 atoms for the same variance. By comparison, SHMC gave a maximum speedup of only 1.6 over HMC. S2HMC has the additional advantage of not requiring any user parameters beyond those of HMC. S2HMC is available in the program PROTOMOL 2.1. A Python version, adequate for didactic purposes, is also in MDL (http://mdlab.sourceforge.net/s2hmc).

  18. 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.

  19. 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 ...

  20. 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/

  1. Binary black hole shadows, chaotic scattering and the Cantor set

    CERN Document Server

    Shipley, Jake

    2016-01-01

    We investigate the qualitative features of binary black hole shadows using the model of two extremally charged black holes in static equilibrium (a Majumdar--Papapetrou solution). Our perspective is that binary spacetimes are natural exemplars of {\\it chaotic scattering}, because they admit more than one fundamental null orbit, and thus an uncountably-infinite set of perpetual orbits which generate scattering singularities in initial data. Inspired by the three-disc model, we develop an appropriate symbolic dynamics to describe planar null geodesics on the double black hole spacetime. We show that a one-dimensional (1D) black hole shadow may constructed through an iterative procedure akin to the construction of the Cantor set; thus the shadow is self-similar. Next, we study non-planar rays, to understand how angular momentum affects the existence and properties of the fundamental null orbits. Taking slices through 2D shadows, we observe three types of 1D shadow: regular, Cantor-like, and highly chaotic. The s...

  2. REAL-TIME SHADOW USING A COMBINATION OF STENCIL AND THE Z-BUFFER

    Directory of Open Access Journals (Sweden)

    Hoshang Kolivand

    2011-08-01

    Full Text Available In this paper we describe a real-time shadow generation with volume shadow algorithm in virtual environment that is illuminated by light sources with possibility to move separately. This algorithm uses the combination of stencil and Z-buffers to generate shadow volume. It is simple to understand and implement. We have significantly improved and implemented recent techniques that are used in shadow volume algorithms using stencil buffers especially in order to recognize silhouette, reduce the number of shadow polygons and also redundant length of each triangles that makes the volume shadow. This work may be applied in commercial games or other virtual reality systems.

  3. Shadow education: Effects on students’ self-efficacy in science

    Directory of Open Access Journals (Sweden)

    Darryl Roy Tabasa Montebon

    2016-01-01

    Full Text Available This study aims to investigate the effect of shadow education on students’ self-efficacy. Shadow education or tutoring mimics the mainstream form of education (Bray, 1999 while self-efficacy is a personal judgment of one’s capability to plan and execute a course of action to achieve a certain goal (Bandura, 1977 as cited by Zimmerman, 2000. Results of this study described the tutorial background of the respondents and their self-efficacy levels. It has been found out that students’ self-efficacy due to exposure to shadow education is high. The self-efficacy of students does not necessarily vary when compared by gender, grade level, and the length of time that respondents have been going to tutorial sessions.

  4. Self-shadowing in ballistic fan formation from point seeds

    Science.gov (United States)

    Pelliccione, M.; Lu, T.-M.

    2007-06-01

    We utilize the model of ballistic aggregation to investigate the growth of particles on a point seed under various oblique particle fluxes to model nanorod growth at early deposition times. In particular, we show that the angular nature of the particle flux leads to a self-shadowing behavior, where features of an individual aggregate can shadow other features of the same aggregate. We quantify the shape of the aggregates by the growth exponent p , where the radius of the aggregate R is related to the height of the aggregate z as Rtilde zp . We show that the self-shadowing effect is the dominant factor that controls the evolution of nanorod size during oblique angle deposition. The simulation predictions are consistent with recent experimental results.

  5. Black hole shadows in fourth-order conformal Weyl gravity

    CERN Document Server

    Mureika, Jonas R

    2016-01-01

    We calculate the characteristics of the "black hole shadow" for a rotating, neutral black hole in fourth-order conformal Weyl gravity. It is shown that the morphology is not significantly affected by the underlying framework, except for very large masses. Conformal gravity black hole shadows would also significantly differ from their general relativistic counterparts if the values of the main conformal gravity parameters, $\\gamma$ and $\\kappa$, were increased by several orders of magnitude. Such increased values for $\\gamma$ and $\\kappa$ are currently ruled out by gravitational phenomenology. Therefore, it is unlikely that these differences in black hole shadows will be detected in future observations, carried out by the Event Horizon Telescope or others such experiments.

  6. Shadow mask assisted heteroepitaxy of compound semiconductor nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Schallenberg, T.

    2004-07-01

    Shadow Mask assisted Molecular Beam Epitaxy (SMMBE) is a technique enabling selected area epitaxy of semiconductor heterostructures through shadow masks. The objective of this work was the development of the SMMBE technique for the reliable fabrication of compound semiconductor nanostructures of high structural and optical quality. In order to accomplish this, technological processes have been developed and optimized. One of the technological developments to this effect, which has substantially enhanced the versatility of SMMBE, is the introduction of a new type of freestanding shadow masks. A consistent model has been developed, which successfully explains the growth dynamics of molecular beam epitaxy through shadow masks. The predictions of the model regarding the growth of II-VI and III-V compounds have been tested experimentally and the dependence of the growth rates on the growth parameters has been verified. Moreover, it has been shown, that selected area epitaxy of II-VI and III-V compounds are governed by different surface kinetics. In addition to the basic surface kinetic processes described by the model, the roles of orientation and strain-dependent growth dynamics, partial shadow, and material deposition on the mask (closure of apertures) have been discussed. The resulting advanced understanding of the growth dynamics (model and basic experiments) in combination with the implementation of technical improvements has enabled the development and application of a number of different processes for the fabrication of both II-VI and III-V nanostructures. In addition to specific material properties, various other phenomena have been exploited, e.g., self-organization. Bright cathodoluminescence demonstrates that the resulting quantum structures are of high structural and optical quality. In addition to these results the limitations of the method have also been discussed, and various approaches to overcome them have been suggested. Moreover, propositions for the

  7. Binary black hole shadows, chaotic scattering and the Cantor set

    Science.gov (United States)

    Shipley, Jake O.; Dolan, Sam R.

    2016-09-01

    We investigate the qualitative features of binary black hole shadows using the model of two extremally charged black holes in static equilibrium (a Majumdar-Papapetrou solution). Our perspective is that binary spacetimes are natural exemplars of chaotic scattering, because they admit more than one fundamental null orbit, and thus an uncountably infinite set of perpetual null orbits which generate scattering singularities in initial data. Inspired by the three-disc model, we develop an appropriate symbolic dynamics to describe planar null geodesics on the double black hole spacetime. We show that a one-dimensional (1D) black hole shadow may be constructed through an iterative procedure akin to the construction of the Cantor set; thus the 1D shadow is self-similar. Next, we study non-planar rays, to understand how angular momentum affects the existence and properties of the fundamental null orbits. Taking slices through 2D shadows, we observe three types of 1D shadow: regular, Cantor-like, and highly chaotic. The switch from Cantor-like to regular occurs where outer fundamental orbits are forbidden by angular momentum. The highly chaotic part is associated with an unexpected feature: stable and bounded null orbits, which exist around two black holes of equal mass M separated by {a}1\\lt a\\lt \\sqrt{2}{a}1, where {a}1=4M/\\sqrt{27}. To show how this possibility arises, we define a certain potential function and classify its stationary points. We conjecture that the highly chaotic parts of the 2D shadow possess the Wada property. Finally, we consider the possibility of following null geodesics through event horizons, and chaos in the maximally extended spacetime.

  8. Magnetic Random Access Memory; Integrated Passive Components

    Science.gov (United States)

    2010-06-02

    for an inductor designed to  operate at 10 MHz, a reasonable value for  switching  power converters. The  ferrite  cladding  works optimally when applied to...elements: a magnetic latch , and a magnetic shadow memory to serve as a backup to volatile electronic memory. Integrated Passive Electronic Components...greater inductance per unit area, and a 150% increase in Q, by using ferrite cladding contain and shape electromagnetic fields. 15. SUBJECT TERMS

  9. Near-wall velocity measurements by Particle-Shadow-Tracking

    CERN Document Server

    Lancien, Pierre; Métivier, François; 10.1007/s00348-007-0260-z

    2009-01-01

    We report a new method to measure the velocity of a fluid in the vicinity of a wall. The method, that we call Particle-Shadow Tracking (PST), simply consists in seeding the fluid with a small number of fine tracer particles of density close to that of the fluid. The position of each particle and of its shadow on the wall are then tracked simultaneously, allowing one to accurately determine the distance separating tracers from the wall and therefore to extract the velocity field. We present an application of the method to the determination of the velocity profile inside a laminar density current flowing along an inclined plane.

  10. Medium Access Control for Opportunistic Concurrent Transmissions under Shadowing Channels

    Directory of Open Access Journals (Sweden)

    Seung Min Hur

    2009-06-01

    Full Text Available We study the problem of how to alleviate the exposed terminal effect in multihop wireless networks in the presence of log-normal shadowing channels. Assuming node location information, we propose an extension of the IEEE 802.11 MAC protocol that schedules concurrent transmissions in the presence of log-normal shadowing, thus mitigating the exposed terminal problem and improving network throughput and delay performance. We observe considerable improvements in throughput and delay achieved over the IEEE 802.11 MAC under various network topologies and channel conditions in ns-2 simulations, which justify the importance of considering channel randomness in MAC protocol design for multihop wireless networks.

  11. 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...

  12. Defining solar park location using shadow over time detection method

    Science.gov (United States)

    Martynov, Ivan; Kauranne, Tuomo

    2016-06-01

    There is nowadays a high demand for research on using renewable sources of energy including solar energy. The availability of stable and efficient solar energy is of paramount importance. Therefore, it is vital to install solar panels in locations which are most of the time not in shadow. To illustrate this idea we have developed a shadow identification method for digital elevation models (DEMs) using the computational means of MATLAB whose environment and tools allow fast and easy image processing. As a source of DEMs we use the Shuttle Radar Topography Mission (SRTM) database since it covers most of the terrain of our planet.

  13. The shadow system in coordinate space: The shadow system in coordinate space: A locally explicable system that violates Bell's inequality

    CERN Document Server

    Leffler, Warren

    2009-01-01

    We explore the consequences of denying the "emptiness of paths not taken," EPNT, a premise of Bernstein, Greenberger, Horne, and Zeilinger in their paper titled, Bell theorem without inequalities. Carrying out the negation of EPNT leads to the concept of a "shadow stream." Streams are essentially particle implementations of the path amplitudes in Feynman's formulation of quantum mechanics, resulting in a simple and consistent extension of the standard postulates for quantum mechanics. Following up on the negation of EPNT using shadow streams, we analyze the experimental outcomes in a standard two-particle interferometer. The result is a simple counterexample to Bell's theorem in position/momentum space.

  14. Memory Matters

    Science.gov (United States)

    ... Emergency Room? What Happens in the Operating Room? Memory Matters KidsHealth > For Kids > Memory Matters A A ... of your complex and multitalented brain. What Is Memory? When an event happens, when you learn something, ...

  15. MEMORY MODULATION

    Science.gov (United States)

    Roozendaal, Benno; McGaugh, James L.

    2011-01-01

    Our memories are not all created equally strong: Some experiences are well remembered while others are remembered poorly, if at all. Research on memory modulation investigates the neurobiological processes and systems that contribute to such differences in the strength of our memories. Extensive evidence from both animal and human research indicates that emotionally significant experiences activate hormonal and brain systems that regulate the consolidation of newly acquired memories. These effects are integrated through noradrenergic activation of the basolateral amygdala which regulates memory consolidation via interactions with many other brain regions involved in consolidating memories of recent experiences. Modulatory systems not only influence neurobiological processes underlying the consolidation of new information, but also affect other mnemonic processes, including memory extinction, memory recall and working memory. In contrast to their enhancing effects on consolidation, adrenal stress hormones impair memory retrieval and working memory. Such effects, as with memory consolidation, require noradrenergic activation of the basolateral amygdala and interactions with other brain regions. PMID:22122145

  16. Bow and stern waves triggered by the Moon's shadow boat

    National Research Council Canada - National Science Library

    J. Y. Liu; Y. Y. Sun; Y. Kakinami; C. H. Chen; C. H. Lin; H. F. Tsai

    2011-01-01

    ...) derived from ground-based GPS receivers in Taiwan and Japan. We not only find the feature of the predicted bow wave but also the stern wave on the equator side of the eclipse path, as well as the stern wake right behind the Moon's shadow boat...

  17. 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.

  18. 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.

  19. Dark Matter Trapping by Stellar Bars: The Shadow Bar

    Science.gov (United States)

    Petersen, Michael S.; Weinberg, Martin D.; Katz, Neal

    2016-09-01

    We investigate the complex interactions between the stellar disc and the dark-matter halo during bar formation and evolution using N-body simulations with fine temporal resolution and optimally chosen spatial resolution. We find that the forming stellar bar traps dark matter in the vicinity of the stellar bar into bar-supporting orbits. We call this feature the shadow bar. The shadow bar modifies both the location and magnitude of the angular momentum transfer between the disc and dark matter halo and adds 10 per cent to the mass of the stellar bar over 4 Gyr. The shadow bar is potentially observable by its density and velocity signature in spheroid stars and by direct dark matter detection experiments. Numerical tests demonstrate that the shadow bar can diminish the rate of angular momentum transport from the bar to the dark matter halo by more than a factor of three over the rate predicted by dynamical friction with an untrapped dark halo, and thus provides a possible physical explanation for the observed prevalence of fast bars in nature.

  20. Dark Matter Trapping by Stellar Bars: The Shadow Bar

    CERN Document Server

    Petersen, Michael S; Katz, Neal

    2016-01-01

    We investigate the complex interactions between the stellar disc and the dark-matter halo during bar formation and evolution using N-body simulations with fine temporal resolution and optimally chosen spatial resolution. We find that the forming stellar bar traps dark matter in the vicinity of the stellar bar into bar-supporting orbits. We call this feature the shadow bar. The shadow bar modifies both the location and magnitude of the angular momentum transfer between the disc and dark matter halo and adds 10 per cent to the mass of the stellar bar over 4 Gyr. The shadow bar is potentially observable by its density and velocity signature in spheroid stars and by direct dark matter detection experiments. Numerical tests demonstrate that the shadow bar can diminish the rate of angular momentum transport from the bar to the dark matter halo by more than a factor of three over the naive dynamical friction prediction, and thus provides a possible physical explanation for the observed prevalence of fast bars in nat...

  1. 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...

  2. Dark matter trapping by stellar bars: the shadow bar

    Science.gov (United States)

    Petersen, Michael S.; Weinberg, Martin D.; Katz, Neal

    2016-12-01

    We investigate the complex interactions between the stellar disc and the dark-matter halo during bar formation and evolution using N-body simulations with fine temporal resolution and optimally chosen spatial resolution. We find that the forming stellar bar traps dark matter in the vicinity of the stellar bar into bar-supporting orbits. We call this feature the shadow bar. The shadow bar modifies both the location and magnitude of the angular momentum transfer between the disc and dark matter halo and adds 10 per cent to the mass of the stellar bar over 4 Gyr. The shadow bar is potentially observable by its density and velocity signature in spheroid stars and by direct dark matter detection experiments. Numerical tests demonstrate that the shadow bar can diminish the rate of angular momentum transport from the bar to the dark matter halo by more than a factor of 3 over the rate predicted by dynamical friction with an untrapped dark halo, and thus provides a possible physical explanation for the observed prevalence of fast bars in nature.

  3. 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.

  4. Moon and Sun shadow observation with IceCube

    Energy Technology Data Exchange (ETDEWEB)

    Bos, Fabian; Tenholt, Frederik; Becker-Tjus, Julia [Theoretische Physik, Ruhr-Universitaet, Bochum (Germany); Westerhoff, Stefan [University of Wisconsin, Madison (United States); Collaboration: IceCube-Collaboration

    2015-07-01

    The analysis of the Moon shadow is a standard method in IceCube to determine the angular resolution and absolute pointing capabilities of the IceCube detector at the geographic South Pole. The Sun has not been used as a calibrator thus far, as its shadow is expected to be influenced by the solar magnetic field, which deflects the cosmic rays near the solar surface. This, on the other hand, provides indirect pieces of information on the magnetic field structure of the Sun. This talk shows a first analysis of the Sun shadow with IceCube data. The analysis is based on the data of the detector configurations with 79 (IC79) and 86 strings (IC86) from 2010 through 2012. To examine the shadows, a binned method is used to compare all events from one on-source with two off-source windows. For the IC40 and IC59 configuration a deficit with a statistical significance of more than 6σ was observed.

  5. Optical Algorithm for Cloud Shadow Detection Over Water

    Science.gov (United States)

    2013-02-01

    5] R. Amin, A. Gilerson, J. Zhou, B. Gross, F. Moshary, and S. Ahmed, "Im- pacts of atmospheric corrections on algal bloom detection techniques...optical algorithms to detect and classify harmful algal blooms from space. His current research interests include optical algorithm development...algorithm, remote sensing, shadow detection 16. SECURITY CLASSIFICATION OF: a. REPORT Unclassified b. ABSTRACT Unclassified c. THIS PAGE

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

    Science.gov (United States)

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

    2016-05-01

    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.

  7. 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…

  8. 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…

  9. School Socioeconomic Compositional Effect on Shadow Education Participation: Evidence from Japan

    Science.gov (United States)

    Matsuoka, Ryoji

    2015-01-01

    While shadow education, organized learning activities outside formal school, has grown greatly around the world, the relationship between formal schooling and shadow education has not been well investigated. This study is therefore intended to empirically test whether formal education's structure (i.e. tracking) affects students' shadow education…

  10. THE IMPACT OF SHADOWS IN THE RECENT INDIAN REMOTE SENSING SATELLITE IMAGERY

    Directory of Open Access Journals (Sweden)

    Mrs. G.Devi

    2011-08-01

    Full Text Available Remote sensing technology is emerging as a strong tool to extract information about the earth resources from the satellite imagery. However, shadow in fine resolution imagery affects this information. The fine resolution images from recent Indian Remote Sensing (IRS satellites are compared for the pixel values in shadow and non-shadow areas using histogram occupy large shadow area compared to Cartosat-1 of resolution 2.5m. The solar elevation angle is 41degree for which long shadows are formed in case of Cartosat-2 images. The solarelevation angle is 59 degree for which short shadows are formed in case of Cartosat-1 images. The shadows in an image are a function of the solar elevation angle, azimuth angle and spatial resolution etc. The fine resolution image (Cartosat-2 building and their shadow pixel values are analysed by bimodal histogram splitting technique. The shadow boundaries are extracted. Finally Gamma filtering applied and with the Gaussian enhancement technique the shadows are eliminated from Cartosat-2 image. The building shadow under objectcan be identified in this method. The main application in shadow elimination is used for urban map preparation and the object oriented classification.

  11. Depth perception from moving cast shadow in macaque monkey.

    Science.gov (United States)

    Mizutani, Saneyuki; Usui, Nobuo; Yokota, Takanori; Mizusawa, Hidehiro; Taira, Masato; Katsuyama, Narumi

    2015-07-15

    In the present study, we investigate whether the macaque monkey can perceive motion in depth using a moving cast shadow. To accomplish this, we conducted two experiments. In the first experiment, an adult Japanese monkey was trained in a motion discrimination task in depth by binocular disparity. A square was presented on the display so that it appeared with a binocular disparity of 0.12 degrees (initial position), and moved toward (approaching) or away from (receding) the monkey for 1s. The monkey was trained to discriminate the approaching and receding motion of the square by GO/delayed GO-type responses. The monkey showed a significantly high accuracy rate in the task, and the performance was maintained when the position, color, and shape of the moving object were changed. In the next experiment, the change in the disparity was gradually decreased in the motion discrimination task. The results showed that the performance of the monkey declined as the distance of the approaching and receding motion of the square decreased from the initial position. However, when a moving cast shadow was added to the stimulus, the monkey responded to the motion in depth induced by the cast shadow in the same way as by binocular disparity; the reward was delivered randomly or given in all trials to prevent the learning of the 2D motion of the shadow in the frontal plane. These results suggest that the macaque monkey can perceive motion in depth using a moving cast shadow as well as using binocular disparity.

  12. Shadow Enhancers Are Pervasive Features of Developmental Regulatory Networks.

    Science.gov (United States)

    Cannavò, Enrico; Khoueiry, Pierre; Garfield, David A; Geeleher, Paul; Zichner, Thomas; Gustafson, E Hilary; Ciglar, Lucia; Korbel, Jan O; Furlong, Eileen E M

    2016-01-11

    Embryogenesis is remarkably robust to segregating mutations and environmental variation; under a range of conditions, embryos of a given species develop into stereotypically patterned organisms. Such robustness is thought to be conferred, in part, through elements within regulatory networks that perform similar, redundant tasks. Redundant enhancers (or "shadow" enhancers), for example, can confer precision and robustness to gene expression, at least at individual, well-studied loci. However, the extent to which enhancer redundancy exists and can thereby have a major impact on developmental robustness remains unknown. Here, we systematically assessed this, identifying over 1,000 predicted shadow enhancers during Drosophila mesoderm development. The activity of 23 elements, associated with five genes, was examined in transgenic embryos, while natural structural variation among individuals was used to assess their ability to buffer against genetic variation. Our results reveal three clear properties of enhancer redundancy within developmental systems. First, it is much more pervasive than previously anticipated, with 64% of loci examined having shadow enhancers. Their spatial redundancy is often partial in nature, while the non-overlapping function may explain why these enhancers are maintained within a population. Second, over 70% of loci do not follow the simple situation of having only two shadow enhancers-often there are three (rols), four (CadN and ade5), or five (Traf1), at least one of which can be deleted with no obvious phenotypic effects. Third, although shadow enhancers can buffer variation, patterns of segregating variation suggest that they play a more complex role in development than generally considered.

  13. In the Shadow/from the Shadow: The Principal as a Reflective Practitioner in Trinidad and Tobago

    Science.gov (United States)

    Bristol, Laurette; Esnard, Talia; Brown, Launcelot

    2015-01-01

    This case highlights a school principal's leading practice as she worked to transform the social and educational status of students, teachers, and community in a small urban primary school. We employ shadowing, a technique popularized in work-based education and photography, as reflective and research tools. Teaching notes provide insight into the…

  14. Shadows constructing a relationship between light and color pigments by physical and mathematical perspectives

    Science.gov (United States)

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

    2017-03-01

    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. This integration of physical and mathematical reasoning not only manages an operational approach to the concept of shadows, it also outputs a model that can be used in science, technology, engineering and mathematics (STEM) curricula by providing a concrete and physical example for abstract concept of the empty set.

  15. REAL-TIME SHADOW USING A COMBINATION OF STENCIL AND THE Z-BUFFER

    Directory of Open Access Journals (Sweden)

    Hoshang Kolivand

    2011-09-01

    Full Text Available In this paper we describe a real-time shadow generation with volume shadow algorithm in virtualenvironment that is illuminated by light sources with possibility to move separately. This algorithm uses thecombination of stencil and Z-buffers to generate shadow volume. It is simple to understand and implement.We have significantly improved and implemented recent techniques that are used in shadow volumealgorithms using stencil buffers especially in order to recognize silhouette, reduce the number of shadowpolygons and also redundant length of each triangles that makes the volume shadow. This work may beapplied in commercial games or other virtual reality systems

  16. 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...

  17. 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.

  18. Shadows and spirals in the protoplanetary disk HD 100453

    Science.gov (United States)

    Benisty, M.; Stolker, T.; Pohl, A.; de Boer, J.; Lesur, G.; Dominik, C.; Dullemond, C. P.; Langlois, M.; Min, M.; Wagner, K.; Henning, T.; Juhasz, A.; Pinilla, P.; Facchini, S.; Apai, D.; van Boekel, R.; Garufi, A.; Ginski, C.; Ménard, F.; Pinte, C.; Quanz, S. P.; Zurlo, A.; Boccaletti, A.; Bonnefoy, M.; Beuzit, J. L.; Chauvin, G.; Cudel, M.; Desidera, S.; Feldt, M.; Fontanive, C.; Gratton, R.; Kasper, M.; Lagrange, A.-M.; LeCoroller, H.; Mouillet, D.; Mesa, D.; Sissa, E.; Vigan, A.; Antichi, J.; Buey, T.; Fusco, T.; Gisler, D.; Llored, M.; Magnard, Y.; Moeller-Nilsson, O.; Pragt, J.; Roelfsema, R.; Sauvage, J.-F.; Wildi, F.

    2017-01-01

    Context. Understanding the diversity of planets requires studying the morphology and physical conditions in the protoplanetary disks in which they form. Aims: We aim to study the structure of the 10 Myr old protoplanetary disk HD 100453, to detect features that can trace disk evolution and to understand the mechanisms that drive these features. Methods: We observed HD 100453 in polarized scattered light with VLT/SPHERE at optical (0.6 μm, 0.8 μm) and near-infrared (1.2 μm) wavelengths, reaching an angular resolution of 0.02'', and an inner working angle of 0.09''. Results: We spatially resolve the disk around HD 100453, and detect polarized scattered light up to 0.42'' ( 48 au). We detect a cavity, a rim with azimuthal brightness variations at an inclination of 38° with respect to our line of sight, two shadows and two symmetric spiral arms. The spiral arms originate near the location of the shadows, close to the semi major axis. We detect a faint feature in the SW that can be interpreted as the scattering surface of the bottom side of the disk, if the disk is tidally truncated by the M-dwarf companion currently seen at a projected distance of 119 au. We construct a radiative transfer model that accounts for the main characteristics of the features with an inner and outer disk misaligned by 72°. The azimuthal brightness variations along the rim are well reproduced with the scattering phase function of the model. While spirals can be triggered by the tidal interaction with the companion, the close proximity of the spirals to the shadows suggests that the shadows could also play a role. The change in stellar illumination along the rim induces an azimuthal variation of the scale height that can contribute to the brightness variations. Conclusions: Dark regions in polarized images of transition disks are now detected in a handful of disks and often interpreted as shadows due to a misaligned inner disk. However, the origin of such a misalignment in HD 100453, and

  19. 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

  20. Medium Access Control for Opportunistic Concurrent Transmissions under Shadowing Channels.

    Science.gov (United States)

    Son, In Keun; Mao, Shiwen; Hur, Seung Min

    2009-01-01

    We study the problem of how to alleviate the exposed terminal effect in multi-hop wireless networks in the presence of log-normal shadowing channels. Assuming node location information, we propose an extension of the IEEE 802.11 MAC protocol that sched-ules concurrent transmissions in the presence of log-normal shadowing, thus mitigating the exposed terminal problem and improving network throughput and delay performance. We observe considerable improvements in throughput and delay achieved over the IEEE 802.11 MAC under various network topologies and channel conditions in ns-2 simulations, which justify the importance of considering channel randomness in MAC protocol design for multi-hop wireless networks.

  1. Least Squares Shadowing for Sensitivity Analysis of Turbulent Fluid Flows

    CERN Document Server

    Blonigan, Patrick; Wang, Qiqi

    2014-01-01

    Computational methods for sensitivity analysis are invaluable tools for aerodynamics research and engineering design. However, traditional sensitivity analysis methods break down when applied to long-time averaged quantities in turbulent fluid flow fields, specifically those obtained using high-fidelity turbulence simulations. This is because of a number of dynamical properties of turbulent and chaotic fluid flows, most importantly high sensitivity of the initial value problem, popularly known as the "butterfly effect". The recently developed least squares shadowing (LSS) method avoids the issues encountered by traditional sensitivity analysis methods by approximating the "shadow trajectory" in phase space, avoiding the high sensitivity of the initial value problem. The following paper discusses how the least squares problem associated with LSS is solved. Two methods are presented and are demonstrated on a simulation of homogeneous isotropic turbulence and the Kuramoto-Sivashinsky (KS) equation, a 4th order c...

  2. X-Ray Shadowing Experiments Toward Infrared Dark Clouds

    Science.gov (United States)

    Anderson, L. E.; Snowden, S.; Bania, T. M.

    2009-01-01

    We searched for X-ray shadowing toward two infrared dark clouds (IRDCs) using the MOS detectors on XMM-Newton to learn about the Galactic distribution of X-ray emitting plasma. IRDCs make ideal X-ray shadowing targets of 3/4 keY photons due to their high column densities, relatively large angular sizes, and known kinematic distances. Here we focus on two clouds near 30 deg Galactic longitude at distances of 2 and 5 kpc from the Sun. We derive the foreground and background column densities of molecular and atomic gas in the direction of the clouds. We find that the 3/4 ke V emission must be distributed throughout the Galactic disk. It is therefore linked to the structure of the cooler material of the ISM, and to the birth of stars.

  3. The permanently shadowed regions of dwarf planet Ceres

    Science.gov (United States)

    Schorghofer, Norbert; Mazarico, Erwan; Platz, Thomas; Preusker, Frank; Schröder, Stefan E.; Raymond, Carol A.; Russell, Christopher T.

    2016-07-01

    Ceres has only a small spin axis tilt (4°), and craters near its rotational poles can experience permanent shadow and trap volatiles, as is the case on Mercury and on Earth's Moon. Topography derived from stereo imaging by the Dawn spacecraft is used to calculate direct solar irradiance that defines the extent of the permanently shadowed regions (PSRs). In the northern polar region, PSRs cover ˜1800 km2 or 0.13% of the hemisphere, and most of the PSRs are cold enough to trap water ice over geological time periods. Based on modeling of the water exosphere, water molecules seasonally reside around the winter pole and ultimately an estimated 0.14% of molecules get trapped. Even for the lowest estimates of the amount of available water, this predicts accumulation rates in excess of loss rates, and hence, there should be fresh ice deposits in the cold traps.

  4. Simulation of Hard Shadows on Large Spherical Terrains

    Science.gov (United States)

    Aslandere, Turgay; Flatken, Markus; Gerndt, Andreas

    2016-12-01

    Real-time rendering of high precision shadows using digital terrain models as input data is a challenging task. Especially when interactivity is targeted and level of detail data structures are utilized to tackle huge amount of data. In this paper, we present a real-time rendering approach for the computation of hard shadows using large scale digital terrain data obtained by satellite imagery. Our approach is based on an extended horizon mapping algorithm that avoids costly pre-computations and ensures high accuracy. This algorithm is further developed to handle large data. The proposed algorithms take the surface curvature of the large spherical bodies into account during the computation. The performance issues are discussed and the results are presented. The generated images can be exploited in 3D research and aerospace related areas.

  5. 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.

  6. The Effect of Shadow Economy – Country'S Tax Losses

    Directory of Open Access Journals (Sweden)

    Jolita Krumplytė

    2011-04-01

    Full Text Available The article analyzes the content of shadow economy through the prism of the tax administration. The author provides the limitations of the study and methodologically based relationship between the shadow economy and the tax revenue not to be received to the national consolidate budget. Country’s tax losses (tax gap is the amount of the tax revenue that is not received to the country's consolidated budget in the tax non-payment effects: tax avoidance and tax evasion. Tax losses (tax gap is treated as the difference between the amount of potential taxes and contributions that could be collected if the taxpayers correctly calculated and paid on time in accordance with the provisions of the legislation and actually paid taxes and contributions.Article in Lithuanian

  7. Shadow photogrammetric apparatus for the quantitative evaluation of corneal buttons.

    Science.gov (United States)

    Denham, D; Mandelbaum, S; Parel, J M; Holland, S; Pflugfelder, S; Parel, J M

    1989-11-01

    We have developed a technique for the accurate, quantitative, geometric evaluation of trephined and punched corneal buttons. A magnified shadow of the frontal and edge views of a corneal button mounted on the rotary stage of a modified optical comparator is projected onto the screen of the comparator and photographed. This process takes approximately three minutes. The diameters and edge profile at any meridian photographed can subsequently be analyzed from the film. The precision in measuring the diameters of well cut corneal buttons is +/- 23 microns, and in measuring the angle of the edge profile is +/- 1 degree. Statistical analysis of inter observer variability indicated excellent reproducibility of measurements. Shadow photogrammetry offers a standardized, accurate, and reproducible method for analysis of corneal trephination.

  8. 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)

  9. Examining the Fidelity of Climate model via Shadowing Time

    Science.gov (United States)

    Du, H.; Smith, L. A.

    2015-12-01

    Fully fledged climate models provide the best available simulations for reflecting the future, yet we have scant insight into their fidelity, in particular as to the duration into the future at which the real world should be expected to evolve in a manner today's models cannot foresee. We know now that our best available models are not adequate for many sought after purposes. To throw some light on the maximum fidelity expected from a given generation of models, and thereby aid both policy making and model development, we can test the weaknesses of a model as a dynamical system to get an informed idea of its potential applicability at various lead times. Shadowing times reflect the duration on which a GCM reflects the observations; extracting the shortcomings of the model which limit shadowing times allows informed speculation regarding the fidelity of the model in the future. More specifically, the relevant phenomena limiting model fidelity can be learned by identifying the reasons models cannot shadow; the time scales on which feedbacks on the system (which are not active in the model) are likely to result in model irrelevance can be discerned. The methodology is developed in the "low dimensional laboratory" of relatively simple dynamical systems, for example Lorenz 95 systems. The results are presented in Lorenz 95 systems, high dimensional fluid dynamical simulations of rotating annulus and GCMs. There are severe limits on the light shadowing experiments can shine on GCM predictions. Never the less, they appear to be one of the brightest lights we can shine to illuminate the likely fidelity of GCM extrapolations into the future.

  10. 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.

  11. Residual stress measurement in silicon sheet by shadow moire interferometry

    Science.gov (United States)

    Kwon, Y.; Danyluk, S.; Bucciarelli, L.; Kalejs, J. P.

    1987-01-01

    A shadow moire interferometry technique has been developed to measure residual strain in thin silicon sheet. The curvature of a segment of sheet undergoing four-point bending is analyzed to include the applied bending moments, the in-plane residual stresses, and the 'end effect' of the sheet since it is of finite length. The technique is applied to obtain residual stress distributions for silicon sheet grown by the edge-defined film-fed growth technique.

  12. Nuclear shadowing and antishadowing in a unitarized BFKL equation

    Institute of Scientific and Technical Information of China (English)

    RUAN Jian-Hong; SHEN Zhen-Qi; ZHU Wei

    2008-01-01

    The nuclear shadowing and antishadowing effects are explained by a unitarized BFKL equation.The Q2-and x-variations of the nuclear parton distributions are detailed based on the level of the unintegrated gluon distribution.In particular,the asymptotical behavior of the unintegrated gluon distribution near the saturation limit in nuclear targets is studied. Our results in the nuclear targets are insensitive to the input distributions if the parameters are fixed by the data of a flee proton.

  13. Mirror and Shadow: Social Media in the Burning Man Community

    OpenAIRE

    Aveline, Dawn

    2012-01-01

    Social media forms a mirror for the present and casts a shadow to the future. This exploratory case study focuses on the social media documents created by participants and organizers of the Burning Man festival, a temporary city of 50,000 inhabitants constructed annually in a remote Nevada desert. This ephemeral community develops through the collaborative, volunteer efforts of its citizens. Attendees generate all the content of the event, including large-scale sculptures, performances, and u...

  14. Shadow Prices of Selected Agricultural Commodities – The Czech Case

    OpenAIRE

    Patrik Sieber; Karina Pohlová; Ondřej Chaloupka

    2016-01-01

    The main objective of the paper is to contribute to practical applicability of the CBA in the agricultural sector by exploring the chances to estimate Czech social values of selected agricultural commodities using available statistical data. More specifically, we try to analyse for which commodities secondary data sets are available from which we may deduce the estimates of shadow price ratios, then to estimate SPRs for selected agricultural commodities and to analyse and discuss the ap...

  15. The Shadow Emirate: The Taliban’s Return to Power

    Science.gov (United States)

    2013-06-01

    depends on leaders with charisma and bravado, which at times is at odds with the upper echelon leadership.104 The fighters make up the very bottom of the...Afghanistan: Organizations, Operations, and Shadow Governance,” Institute for the Study of War: Military Analysis and Education for Civilian Leaders ...Supreme Leader , Mullah Omar. Although a bit dated, the material provides a good stepping off point to analyze the group’s dynamic and determine if and how

  16. Acoustic Shadows: An Auditory Exploration of the Sense of Space

    Directory of Open Access Journals (Sweden)

    Frank Dufour

    2011-12-01

    Full Text Available This paper examines the question of auditory detection of the movements of silent objects in noisy environments. The approach to studying and exploring this phenomenon is primarily based on the framework of the ecology of perception defined by James Gibson (Gibson, 1979 in the sense that it focuses on the direct auditory perception of events, or “structured energy that specifies properties of the environment” (Michaels & Carello, 1981 P. 157. The goal of this study is triple: -Theoretical; for various reasons, this kind of acoustic situations has not been extensively studied by traditional acoustics and psychoacoustics, therefore, this project demonstrates and supports the pertinence of the Ecology of Perception for the description and explanation of such complex phenomena. -Practical; like echolocation, perception of acoustic shadows can be improved by practice, this project intends to contribute to the acknowledgment of this way of listening and to help individuals placed in noisy environments without the support of vision acquiring a detailed detection of the movements occurring in these environments. -Artistic; this project explores a new artistic expression based on the creation and exploration of complex multisensory environments. Acoustic Shadows, a multimedia interactive composition is being developed on the premises of the ecological approach to perception. The last dimension of this project is meant to be a contribution to the sonic representation of space in films and in computer generated virtual environments by producing simulations of acoustic shadows.

  17. Real-time simulation of thermal shadows with EMIT

    Science.gov (United States)

    Klein, Andreas; Oberhofer, Stefan; Schätz, Peter; Nischwitz, Alfred; Obermeier, Paul

    2016-05-01

    Modern missile systems use infrared imaging for tracking or target detection algorithms. The development and validation processes of these missile systems need high fidelity simulations capable of stimulating the sensors in real-time with infrared image sequences from a synthetic 3D environment. The Extensible Multispectral Image Generation Toolset (EMIT) is a modular software library developed at MBDA Germany for the generation of physics-based infrared images in real-time. EMIT is able to render radiance images in full 32-bit floating point precision using state of the art computer graphics cards and advanced shader programs. An important functionality of an infrared image generation toolset is the simulation of thermal shadows as these may cause matching errors in tracking algorithms. However, for real-time simulations, such as hardware in the loop simulations (HWIL) of infrared seekers, thermal shadows are often neglected or precomputed as they require a thermal balance calculation in four-dimensions (3D geometry in one-dimensional time up to several hours in the past). In this paper we will show the novel real-time thermal simulation of EMIT. Our thermal simulation is capable of simulating thermal effects in real-time environments, such as thermal shadows resulting from the occlusion of direct and indirect irradiance. We conclude our paper with the practical use of EMIT in a missile HWIL simulation.

  18. 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.

  19. 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

  20. 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.

  1. Shadow of the rotating black hole with quintessential energy in the presence of plasma

    Science.gov (United States)

    Abdujabbarov, Ahmadjon; Toshmatov, Bobir; Stuchlík, Zdeněk; Ahmedov, Bobomurat

    We study the shadow of the rotating black hole with quintessential energy (i) in vacuum, (ii) in the presence of plasma with radial power-law density. For the vacuum case, the quintessential field parameter of the rotating black hole significantly changes the shape of the shadow. With increasing quintessential field parameter, the radius of the shadow also increases. With the increase of the radius of the shadow of the rotating black hole, the quintessential field parameter causes decrease of the distortion of the shadow shape: in the presence of the quintessential field parameter, the shadow of the fast rotating black hole becomes too close to the circle. We assume the distant observer of the black hole shadow to be located near the so-called static radius where the gravitational attraction of the black hole is just balanced by the cosmic repulsion. The shape and size of the shadow of quintessential rotating black hole surrounded by plasma depends on (i) plasma parameters, (ii) black hole spin and (iii) quintessential field parameter. With the increase of the plasma refraction index, the apparent radius of the shadow increases. However, for the large values of the quintessential field parameter, the change of the black hole shadow shape due to the presence of plasma is not significant, i.e. the effect of the quintessential field parameter dominates over the plasma effect.

  2. Anisotropic Scattering Shadow Compensation Method for Remote Sensing Image with Consideration of Terrain

    Science.gov (United States)

    Wang, Qiongjie; Yan, Li

    2016-06-01

    With the rapid development of sensor networks and earth observation technology, a large quantity of high resolution remote sensing data is available. However, the influence of shadow has become increasingly greater due to the higher resolution shows more complex and detailed land cover, especially under the shadow. Shadow areas usually have lower intensity and fuzzy boundary, which make the images hard to interpret automatically. In this paper, a simple and effective shadow (including soft shadow) detection and compensation method is proposed based on normal data, Digital Elevation Model (DEM) and sun position. First, we use high accuracy DEM and sun position to rebuild the geometric relationship between surface and sun at the time the image shoot and get the hard shadow boundary and sky view factor (SVF) of each pixel. Anisotropic scattering assumption is accepted to determine the soft shadow factor mainly affected by diffuse radiation. Finally, an easy radiation transmission model is used to compensate the shadow area. Compared with the spectral detection method, our detection method has strict theoretical basis, reliable compensation result and minor affected by the image quality. The compensation strategy can effectively improve the radiation intensity of shadow area, reduce the information loss brought by shadow and improve the robustness and efficiency of the classification algorithms.

  3. 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.

  4. Memory Modulation

    NARCIS (Netherlands)

    Roozendaal, Benno; McGaugh, James L.

    2011-01-01

    Our memories are not all created equally strong: Some experiences are well remembered while others are remembered poorly, if at all. Research on memory modulation investigates the neurobiological processes and systems that contribute to such differences in the strength of our memories. Extensive evi

  5. Memory Matters

    Science.gov (United States)

    ... the brain that actually make memories harder to recall. previous continue Signs of a Memory Problem A person might — or might not — be ... A doctor will test the person's ability to recall events, names, or places by ... . If the person has memory loss from a head injury, the doctor will ...

  6. Real-Time Projection Shadow with Respect to Sun Position in Virtual Environments

    Directory of Open Access Journals (Sweden)

    Hoshang Kolivand

    2011-11-01

    Full Text Available This paper proposes a real-time software for outdoor rendering to control the shadows position with effect of sun's position. The position of sun plays an important rule for outdoor games. Calculation of sun's position, as a result, position and length of shadows require a lot of attention and preciseness. Julian dating is used to calculate the sun's position in the virtual dome. In addition, of computer graphics, building design is another field that this paper contributes on it. To create shadow, projection shadow is proposed. By calculating the sun's position in the specific date, time and location on the earth, shadow is generated. Length and angle of shadow are two parameters measured for building design and both of them are calculated in this real-time application. Therefore, it can be used for teachers to teach some part of physics about earth orbit and it can be used in building design and commercial games in virtual reality systems.

  7. An efficient approach for shadow detection based on Gaussian mixture model

    Institute of Scientific and Technical Information of China (English)

    韩延祥; 张志胜; 陈芳; 陈恺

    2014-01-01

    An efficient approach was proposed for discriminating shadows from moving objects. In the background subtraction stage, moving objects were extracted. Then, the initial classification for moving shadow pixels and foreground object pixels was performed by using color invariant features. In the shadow model learning stage, instead of a single Gaussian distribution, it was assumed that the density function computed on the values of chromaticity difference or bright difference, can be modeled as a mixture of Gaussian consisting of two density functions. Meanwhile, the Gaussian parameter estimation was performed by using EM algorithm. The estimates were used to obtain shadow mask according to two constraints. Finally, experiments were carried out. The visual experiment results confirm the effectiveness of proposed method. Quantitative results in terms of the shadow detection rate and the shadow discrimination rate (the maximum values are 85.79%and 97.56%, respectively) show that the proposed approach achieves a satisfying result with post-processing step.

  8. Shadow Economy in the Context of Economic Crisis: Circumstance Analysis and the Forecasting of Consequences

    Directory of Open Access Journals (Sweden)

    Alexey Sergeyevich Naidenov

    2013-03-01

    Full Text Available The article is devoted to the problem of estimating dynamic of shadow economy in the context of socio-economic crisis negative influence. Factors and threats supporting the increase of shadow economy during the economic crisis were studied. Current situation in the Ural Federal District with regard to shadow economic activity for the period from 2006 to 2012 was represented. The results of forecasting shadow activity were given in the article on the example of Ural Federal District regions. Data obtained was used for developing target program activities, aimed at minimization of negative influence of shadow economy during the economic crisis. Special attention was given to the problem of improving the effectiveness of international cooperation concerning counteraction of shadow economic activity

  9. Message communications of particular message types between compute nodes using DMA shadow buffers

    Science.gov (United States)

    Blocksome, Michael A.; Parker, Jeffrey J.

    2010-11-16

    Message communications of particular message types between compute nodes using DMA shadow buffers includes: receiving a buffer identifier specifying an application buffer having a message of a particular type for transmission to a target compute node through a network; selecting one of a plurality of shadow buffers for a DMA engine on the compute node for storing the message, each shadow buffer corresponding to a slot of an injection FIFO buffer maintained by the DMA engine; storing the message in the selected shadow buffer; creating a data descriptor for the message stored in the selected shadow buffer; injecting the data descriptor into the slot of the injection FIFO buffer corresponding to the selected shadow buffer; selecting the data descriptor from the injection FIFO buffer; and transmitting the message specified by the selected data descriptor through the data communications network to the target compute node.

  10. 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.

  11. Analyzing Spectral Characteristics of Shadow Area from ADS-40 High Radiometric Resolution Aerial Images

    Science.gov (United States)

    Hsieh, Yi-Ta; Wu, Shou-Tsung; Chen, Chaur-Tzuhn; Chen, Jan-Chang

    2016-06-01

    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.

  12. Fiscal illusion and the shadow economy: Two sides of the same coin?

    OpenAIRE

    Buehn, Andreas; DELL'ANNO, Roberto; Schneider, Friedrich

    2013-01-01

    This paper presents an empirical analysis of the relationship between fiscal illusion and the shadow economy for 104 countries over the period 1989–2009. We argue that both unobservable phenomena are closely linked to each other, as the creation of a fiscal illusion may be helpful if governments want to control shadow economic activities. Using a MIMIC model with two latent variables we confirm previous findings on the driving forces of the shadow economy and identify the main determinants an...

  13. Shadow-based Building Detection and Segmentation in High-resolution Remote Sensing Image

    OpenAIRE

    Dongyue Chen; Shibo Shang; Chengdong Wu

    2014-01-01

    This paper proposes an effective method to extract buildings in high-resolution remote sensing images based on shadow detection. Firstly, a superpixel segmentation algorithm called SLIC is introduced to split the input image into homogeneous patches. LDA-based color features of the patches are extracted for detecting shadow regions. According to the positions of the shadows, an adaptive strategy for seed location and regional growth is developed to accomplish the coarse detection of buildings...

  14. Krüppel Expression Levels Are Maintained through Compensatory Evolution of Shadow Enhancers

    OpenAIRE

    Zeba Wunderlich; Meghan D.J. Bragdon; Ben J. Vincent; Jonathan A. White; Javier Estrada; Angela H. DePace

    2015-01-01

    Many developmental genes are controlled by shadow enhancers—pairs of enhancers that drive overlapping expression patterns. We hypothesized that compensatory evolution can maintain the total expression of a gene, while individual shadow enhancers diverge between species. To test this hypothesis, we analyzed expression driven by orthologous pairs of shadow enhancers from Drosophila melanogaster, Drosophila yakuba, and Drosophila pseudoobscura that control expression of Krüppel, a transcription ...

  15. NATION AS IDENTITY IN AMITAV GHOSH’S THE SHADOW LINES

    Directory of Open Access Journals (Sweden)

    R. Malathi

    2013-01-01

    Full Text Available Amitav Ghosh is a Bengali Indian author, a pioneer of English literature in India, best known for his works in the English language. Amitav Ghosh occupies a rather curious place in the landscape of contemporary English language authors from the Indian subcontinent. Freedom from political colonialism came as a refreshing wind to write and historical nationalist issues such as diaspora, migration, refugees, colonial hegemony; socio-economic and cultural issues like east-west encounter, caste and class etc. become the main concerns of Amitav Ghosh. The present paper is proposed to examine Nation as identity in “The Shadow Lines” which as a memory novel, sketches few historical events like the freedom movement in Bengal, the Second World War and the Partition of India in 1947 and the communal riots in Bangladesh and India. In this novel, Ghosh problematizes nation in his search for identity. Further, the text subverts notions of truth-notions that are rooted in cultural, sociological and historical realities while it exposes the arbitrariness of many kinds of lines, borders both personal and political. Although the personal and political are intertwined “Nation” presents itself as a crucial strand on the reader’s sensibilities.

  16. Real-Time Volume Shadow using Visible-Non Visible Algorithm

    Directory of Open Access Journals (Sweden)

    Hoshang Kolivand

    2011-01-01

    Full Text Available Problem statement: Shadows are most important effect to make realistic games and visually appealing images, but they are poor in frame per second. Silhouette detection is most important phases to create real-time shadow. Approach: Present study describes a real-time shadow generated with volume shadow algorithm using Visible-Non Visible algorithm (VNV in virtual environment illuminated by a movable light source to improve the frame per second. Silhouette detection that is most expensive part of shadow creation was described. Triangular method and VNV method were compared. An improved algorithm for volume shadow was proposed and volume shadow using both methods in C+ Opengl implemented. Results: The VNV algorithm increases the number of Frame Per Second (FPS and as a result decreases the cost of implementation. Conclusion: A verified algorithm for volume shadow makes it easy to understand by everyone how to produce real-time shadow in outdoor and indoor virtual environment. It is possible to use it in current commercial games or other virtual reality systems.

  17. Study on the shadowing effect for optical wave scattering from randomly rough surface

    Institute of Scientific and Technical Information of China (English)

    Lixin Guo(郭立新); Yunhua Wang(王运华); Zhensen Wu(吴振森)

    2004-01-01

    Based on the Kirchhoff approximation for rough surface scattering and by calculating the shadowing function of the rough surface, the formula of the scattering cross section of the dielectric rough surface is presented with consideration of the shadowing effect for the optical wave incidence. It is obtained that in comparison with the conventional Kirchhoff solution, the shadowing effect should not be neglected for the optical wave scattering from the rough surface. The influence of the shadowing effect for different incidence angle, surface root mean square slope, and surface roughness on the scattering cross section is discussed in detail.

  18. Pixel-wise Orthogonal Decomposition for Color Illumination Invariant and Shadow-free Image

    OpenAIRE

    Qu, Liangqiong; Tian, Jiandong; Han, Zhi; Tang, Yandong

    2014-01-01

    In this paper, we propose a novel, effective and fast method to obtain a color illumination invariant and shadow-free image from a single outdoor image. Different from state-of-the-art methods for shadow-free image that either need shadow detection or statistical learning, we set up a linear equation set for each pixel value vector based on physically-based shadow invariants, deduce a pixel-wise orthogonal decomposition for its solutions, and then get an illumination invariant vector for each...

  19. Memory protection

    Science.gov (United States)

    Denning, Peter J.

    1988-01-01

    Accidental overwriting of files or of memory regions belonging to other programs, browsing of personal files by superusers, Trojan horses, and viruses are examples of breakdowns in workstations and personal computers that would be significantly reduced by memory protection. Memory protection is the capability of an operating system and supporting hardware to delimit segments of memory, to control whether segments can be read from or written into, and to confine accesses of a program to its segments alone. The absence of memory protection in many operating systems today is the result of a bias toward a narrow definition of performance as maximum instruction-execution rate. A broader definition, including the time to get the job done, makes clear that cost of recovery from memory interference errors reduces expected performance. The mechanisms of memory protection are well understood, powerful, efficient, and elegant. They add to performance in the broad sense without reducing instruction execution rate.

  20. Low Frequency Shadowing of the Parkes Superb Survey

    Science.gov (United States)

    Bhat, N. D. R.; Kaplan, D. L.; Williams, A.; Wayth, R.

    2017-01-01

    The field of Fast Radio Bursts (FRBs) is rapidly gaining momentum. Since their discovery in the Parkes high time resolution survey (Thornton et al. 2013), the number of reported FRB detections has more than tripled, and measurements have been made of their scattering, scintillation, polarisation and Faraday rotation properties, all of which helped to establish their astrophysical nature. Obser- vational evidence continues to mount in support of their extragalactic origin, and the world-wide competitive race is ramping up as a suite of new and existing instruments are gearing up to find them in large numbers. The SUPERB survey at Parkes has been conceived to realise the important goal of understanding the origin and progenitors of FRBs. An integral part of this survey is co-ordinated multi-wavelength follow-ups and shadowing. Our MWA-based shadowing efforts last year resulted in the first simultaneous multi-frequency observation of an FRB (albeit a non-detection at the MWA), and hence the first broadband limit on the spectral index, as reported in our Nature publication (Keane at al. 2016). After an year-long hiatus the SUPERB survey is scheduled to resume in December 2016. We propose to resume our MWA-based efforts by undertaking effective low-frequency shadowing that is uniquely possible with the MWA. Simultaneous detection of even a single a self-same FRB would bring in a huge science payoff and will yield the first unambiguous constraints on the spectral and scattering properties of FRBs, besides the prospects of sub-arc minute localisation that will be possible with the long baseline array of Phase 2 MWA. We propose to make use of unallocated blocks of time within the schedule, available outside the approved programs and the planned commissioning activities relating to Phase 2. This proposal will thus make excellent use of idle time for an exciting and very important science goal in the nascent field of FRB science.

  1. 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.

  2. An Improved Shadow Maps Algorithm for Real-time Rendering%基于Shadow Maps的实时阴影生成算法改进

    Institute of Scientific and Technical Information of China (English)

    张伟; 奚俊峰

    2011-01-01

    To build vivider shadows for real-time rendering in three-dimensional animation, Shadow Maps algorithm is studied and improved. By taking main value of average segmentation and logarithmic segmentation as the parameter to divide the shadow scene, the perspective aliasing is relieved. And by building and buffing the shadow maps twice with proper offset, the shadow acne, which caused by self-shadow error, is cleared up. The improved algorithm is implemented based on OpenGL with common graphic hardware and Windows XP. It's shown that the algorithm can build high quality shadows with satisfying the demand of the real-time rendering.%为了在三维动画场景中实时生成更逼真的阴影,分析了Shadow Maps 阴影生成算法走样和失真问题的原因.采用平均分割与对数分割相结合的方法改进了透视走样同题,采用双阴影图法改进了自阴影绘制问题.在Windows XP环境中,基于OpenGL库,编程实现了Shadow Maps算法改进.实验表明,在目前流行的硬件配置环境下,改进后的算法在阴影生成过程中能满足实时渲染帧率要求,同时增强虚拟场景阴影质量.

  3. China Folk Shadow Play Performing Group in Austria and Germany

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>Sent by the CPAFFC,the Daoqing Shadow Play Performing Group(alias Shi Family Troupe) of Huanxian County,Gansu Province made a performance tour in Austria and Germany from October 22 to November 5,2007,during which it attended the International Puppet Theatre Festival in Mistelbach of Austria and gave performance at the opening ceremony of the International Puppet Art Festival in Bad Kreuznach of Germany.The performance tour was made at the invitation of the Austrian Association for Promotion of Friendship and Cultural Relations with China(AAPFCRC).

  4. When a giant falls, dwarfs have no shadow

    OpenAIRE

    2011-01-01

    It is said that in times of war old people bury young men. As we live in times of peace, and we are old, youngsters will need to bury us. It is said that we become good people after we die. But some of us were good before dying. They were good, generous and honored, wise and tender, effectively human. Some who passed away used to give us a cozy and protective shadow, and their absence leaves us unsheltered, alone with danger. A long time ago, one of our children asked to us: “When an old wise...

  5. Nuclear Shadowing and Select d+Au Observables

    Science.gov (United States)

    Adeluyi, Adeola; Fai, George

    2007-04-01

    Much of the complexity of the description of d+Au collisions in the framework of perturbative Quantum Chromodynamics (pQCD) derives from effects of the nuclear environment. Here we investigate the effects of the most recent available nuclear shadowing parametrization, the Hirai-Kumano-Nagai (HKN) nuclear parton distribution functions (nPDFs) and the updated Albino-Kniehl-Kramer (AKK) fragmentation functions on three select d+Au collision observables. We compare our results to available experimental data from the STAR and BRAHMS collaborations.

  6. In the shadow of the cell-phone

    DEFF Research Database (Denmark)

    Hansen, Lone Koefoed

    2009-01-01

    Based on discussions of hybrid space as well as the concepts of the database and archive art, the paper analyzes Hasan Elahi’s project “Tracking Transience” (2003-) and relates it to Sophie Calle’s performance “Detective” (1980) while discussing how we can understand the mobile phone as a device ...... to an enormous amount of data, we are left with a feeling of following a shadow or maybe a mirage. This paper explores how the mobile phone affords this playing hide-and-seek, and the way that it provides shelter from the inspecting eye...

  7. 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.

  8. Shadow detection improvement using spectral indices and morphological operators in high resolution images from urban areas

    Science.gov (United States)

    Azevedo, S. C.; Silva, E. A.; Pedrosa, M. M.

    2015-04-01

    While high-resolution remote sensing images have increased application possibilities for urban studies, the large number of shadow areas has created challenges to processing and extracting information from these images. Furthermore, shadows can reduce or omit information from the surface as well as degrading the visual quality of images. The pixels of shadows tend to have lower radiance response within the spectrum and are often confused with low reflectance targets. In this work, a shadow detection method was proposed using a morphological operator for dark pattern identification combined with spectral indices. The aims are to avoid misclassification in shadow identification through properties provided by them on color models and, therefore, to improve shadow detection accuracy. Experimental results were tested applying the panchromatic and multispectral band of WorldView-2 image from Sao Paulo city in Brazil, which is a complex urban environment composed by high objects like tall buildings causing large shadow areas. Black top-hat with area injunction was applied in PAN image and shadow identification performance has improved with index as Normalized Difference Vegetation Index (NDVI) and Normalized Saturation-Value Difference Index (NSDVI) ratio from HSV color space obtained from pansharpened multispectral WV-2 image. An increase in distinction between shadows and others objects was observed, which was tested for the completeness, correctness and quality measures computed, using a created manual shadow mask as reference. Therefore, this method can contribute to overcoming difficulties faced by other techniques that need shadow detection as a first necessary preprocessing step, like object recognition, image matching, 3D reconstruction, etc.

  9. 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 ...

  10. Are passive protostellar disks stable to self-shadowing?

    CERN Document Server

    Dullemond, C P

    2000-01-01

    The uniqueness and stability of irradiated flaring passive protostellar disks is investigated in the context of a simplified set of equations for the vertical height H as a function of radius R. It is found that the well-known flaring disk solution with H ~ R^{9/7} is not unique. Diverging solutions and asymptotically conical (H ~ R) solutions are also found. Moreover, using time-dependent linear perturbation analysis, it is found that the flaring disk solution may become unstable to self-shadowing. A local enhancement in the vertical height alters the functional form of irradiation grazing angle, and causes the 'sunny side' of the enhancement to grow and the 'shadow side' to collapse in a run-away fashion. This instability operates in regions of the disk in which the cooling time is much shorter than the vertical sound crossing time, which may occur in the outer regions of the passive irradiated disk if dust and gas are sufficiently strongly thermally coupled. Processes that may stabilize the disk, which inc...

  11. 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.

  12. 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.

  13. Motion detection in color image sequence and shadow elimination

    Science.gov (United States)

    Shen, Jun

    2004-01-01

    Most of the researches are concentrated on motion detection in gray value image sequences and the methods for motion detection are based on background subtraction or on temporal gray value derivatives. The methods based on background subtraction, including auto-adaptive ones, meet difficulties in presence of illumination changes and of slowly moving objects and need to be re-initialized from time to time. The methods based on temporal derivatives are in general sensible to noise. Color images containing much richer information than the gray value ones, it would be interesting to use them to better detect moving objects. In this paper, we address the problem of motion detection in color image sequences and the problems of illumination changes and shadow elimination. Our motion detection method is based on fuzzy segmentation of the color difference image in help of non-symmetrical π membership functions. The elimination of false moving objects detected due to illumination change is realized by combining the background subtraction method with the temporal derivative method and motion continuity. Shadows are removed by comparing the color of mobile pixels detected in the current frame with that in the precedent frame in HSL color space. Experimental results are reported.

  14. Restricted numerical shadow and geometry of quantum entanglement

    CERN Document Server

    Puchała, Zbigniew; Gawron, Piotr; Dunkl, Charles F; Holbrook, John A; Życzkowski, Karol

    2012-01-01

    The restricted numerical range W_R(A) of an operator A acting on a D-dimensional Hilbert space is defined as a set of all possible expectation values of this operator among pure states which belong to a certain subset R of the of set of pure quantum states of dimension D. One considers for instance the set of real states, or in the case of composite spaces, the set of product states and the set of maximally entangled states. Combining the operator theory with a probabilistic approach we introduce the restricted numerical shadow of A -- a normalized probability distribution on the complex plane supported in W_R(A). Its value at point z in C is equal to the probability that the expectation value is equal to z, where |\\psi> represents a random quantum state in subset R distributed according to the natural measure on this set, induced by the unitarily invariant Fubini--Study measure. Studying restricted shadows of operators of a fixed size D=N_A N_B we analyse the geometry of sets of separable and maximally enta...

  15. Photon Regions and Shadows of Accelerated Black Holes

    CERN Document Server

    Grenzebach, Arne; Lämmerzahl, Claus

    2015-01-01

    In an earlier paper we have analytically determined the photon regions and the shadows of black holes of the Pleba\\'nski class of metrics which are also known as the Kerr-Newman-NUT-(anti-)deSitter metrics. The space-times described by these metrics are characterized by six independent parameters: mass, spin, electric and magnetic charge, gravitomagnetic NUT charge, and the cosmological constant. Here we extend this analysis to the Pleba\\'nski-Demia\\'nski class of metrics which contains, in addition to these six parameters, the so-called acceleration parameter. All these metrics are axially symmetric and stationary solutions to the Einstein-Maxwell equations with a cosmological constant which are of Petrov type D. We derive analytical formulas for the photon regions (i.e., for the regions that contain spherical lightlike geodesics) and for the boundary curve of the shadow as it is seen by an observer at Boyer-Lindquist coordinates $(r_O, \\vartheta _O)$ in the domain of outer communication. Whereas all relevan...

  16. Shadows and spirals in the protoplanetary disk HD 100453

    CERN Document Server

    Benisty, M; Pohl, A; de Boer, J; Lesur, G; Dominik, C; Dullemond, C P; Langlois, M; Min, M; Wagner, K; Henning, T; Juhasz, A; Pinilla, P; Apai, D; van Boekel, R; Garufi, A; Ginski, C; Ménard, F; Pinte, C; Quanz, S P; Zurlo, A; Boccaletti, A; Bonnefoy, M; Beuzit, J L; Chauvin, G; Cudel, M; Desidera, S; Feldt, M; Fontanive, C; Gratton, R; Kasper, M; Lagrange, A -M; LeCoroller, H; Mouillet, D; Mesa, D; Sissa, E; Vigan, A; Antichi, J; Buey, T; Fusco, T; Gisler, D; Llored, M; Magnard, Y; Moeller-Nilsson, O; Pragt, J; Roelfsema, R; Sauvage, J -F; Wildi, F

    2016-01-01

    Understanding the diversity of planets requires to study the morphology and the physical conditions in the protoplanetary disks in which they form. We observed and spatially resolved the disk around the ~10 Myr old protoplanetary disk HD 100453 in polarized scattered light with SPHERE/VLT at optical and near-infrared wavelengths, reaching an angular resolution of ~0.02", and an inner working angle of ~0.09". We detect polarized scattered light up to ~0.42" (~48 au) and detect a cavity, a rim with azimuthal brightness variations and inclined by 38 degrees, two shadows and two symmetric spiral arms. The spiral arms originate near the location of the shadows, close to the semi major axis. We detect a faint spiral-like feature in the SW that can be interpreted as the scattering surface of the bottom side of the disk, if the disk is tidally truncated by the M-dwarf companion currently seen at a projected distance of ~119 au. We construct a radiative transfer model that accounts for the main characteristics of the ...

  17. The sculpting of Jupiter's gossamer rings by its shadow.

    Science.gov (United States)

    Hamilton, Douglas P; Krüger, Harald

    2008-05-01

    Dust near Jupiter is produced when interplanetary impactors collide energetically with small inner moons, and is organized into a main ring, an inner halo, and two fainter and more distant gossamer rings. Most of these structures are constrained by the orbits of the moons Adrastea, Metis, Amalthea and Thebe, but a faint outward protrusion called the Thebe extension behaves differently and has eluded understanding. Here we report on dust impacts detected during the Galileo spacecraft's traversal of the outer ring region: we find a gap in the rings interior to Thebe's orbit, grains on highly inclined paths, and a strong excess of submicrometre-sized dust just inside Amalthea's orbit. We present detailed modelling that shows that the passage of ring particles through Jupiter's shadow creates the Thebe extension and fully accounts for these Galileo results. Dust grains alternately charge and discharge when traversing shadow boundaries, allowing the planet's powerful magnetic field to excite orbital eccentricities and, when conditions are right, inclinations as well.

  18. Explaining UXOR variability with self-shadowed disks

    CERN Document Server

    Dullemond, C P; Acke, B; Van Boekel, R

    2003-01-01

    In this Letter we propose a new view on UX Orionis type variability. The idea is based on the earlier proposal by various authors that UXORs are nearly-edge-on disks in which hydrodynamic fluctuations could cause clumps of dust and gas to cross the line of sight. However, because the standard disk models have a flaring geometry, it is mostly the outer regions of the disk that obscure the star. The time scales for such obscuration events would be too long to match the observed time scales of weeks to months. Recent 2-D self-consistent models of Herbig Ae/Be protoplanetary disks (Dullemond et al. 2002,2003 henceforth D02/DD03), however, have indicated that for Herbig Ae/Be star disks there exists, in addition to the usual flared disks, also a new class of disks: those that are fully self-shadowed. Only their puffed-up inner rim (at the dust evaporation radius) is directly irradiated by the star, while the disk at larger radius resides in the shadow of the rim. For these disks there exist inclinations at which t...

  19. Memory design

    DEFF Research Database (Denmark)

    Tanderup, Sisse

    Mind and Matter - Nordik 2009 Conference for Art Historians Design Matters Contributed Memory design BACKGROUND My research concerns the use of memory categories in the designs by the companies Alessi and Georg Jensen. When Alessi's designers create their products, they are usually inspired...... by cultural forms, often specifically by the concept of memory in philosophy, sociology and psychology, while Danish design traditionally has been focusing on form and function with frequent references to the forms of nature. Alessi's motivation for investigating the concept of memory is that it adds...... a cultural dimension to the design objects, enabling the objects to make an identity-forming impact. Whether or not the concept of memory plays a significant role in Danish design has not yet been elucidated fully. TERMINOLOGY The concept of "memory design" refers to the idea that design carries...

  20. Disputed Memory

    DEFF Research Database (Denmark)

    The world wars, genocides and extremist ideologies of the 20th century are remembered very differently across Central, Eastern and Southeastern Europe, resulting sometimes in fierce memory disputes. This book investigates the complexity and contention of the layers of memory of the troubled 20th...... century in the region. Written by an international group of scholars from a diversity of disciplines, the chapters approach memory disputes in methodologically innovative ways, studying representations and negotiations of disputed pasts in different media, including monuments, museum exhibitions......, individual and political discourse and electronic social media. Analyzing memory disputes in various local, national and transnational contexts, the chapters demonstrate the political power and social impact of painful and disputed memories. The book brings new insights into current memory disputes...

  1. Implicit encoding of extrinsic object properties in stored representations mediating recognition: evidence from shadow-specific repetition priming.

    Science.gov (United States)

    Leek, E Charles; Davitt, Lina I; Cristino, Filipe

    2015-03-01

    This study investigated whether, and under what conditions, stored shape representations mediating recognition encode extrinsic object properties that vary according to viewing conditions. This was examined in relation to cast shadow. Observers (N = 90) first memorised a subset of 3D multi-part novel objects from a limited range of viewpoints rendered with either no shadow, object internal shadow, or both object internal and external (ground) plane shadow. During a subsequent test phase previously memorised targets were discriminated from visually similar distractors across learned and novel views following brief presentation of a same-shape masked prime. The primes contained either matching or mismatching shadow rendering from the training condition. The results showed a recognition advantage for objects memorised with object internal shadow. In addition, objects encoded with internal shadow were primed more strongly by matching internal shadow primes, than by same shape primes with either no shadow or both object internal and external (ground) shadow. This pattern of priming effects generalises to previously unseen views of targets rendered with object internal shadow. The results suggest that the object recognition system contains a level of stored representation at which shape and the extrinsic object property of cast shadow are bound. We propose that this occurs when cast shadow cannot be discounted during perception on the basis of external cues to the scene lighting model.

  2. Main Memory

    OpenAIRE

    Boncz, Peter; Liu, Lei; Özsu, Tamer, M.

    2008-01-01

    Primary storage, presently known as main memory, is the largest memory directly accessible to the CPU in the prevalent Von Neumann model and stores both data and instructions (program code). The CPU continuously reads instructions stored there and executes them. It is also called Random Access Memory (RAM), to indicate that load/store instructions can access data at any location at the same cost, is usually implemented using DRAM chips, which are connected to the CPU and other peripherals (di...

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

    NARCIS (Netherlands)

    Linden, van der Wim 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. Sec

  4. Implementing Content Constraints in Alpha-Stratified Adaptive Testing Using a Shadow Test Approach. Research Report.

    Science.gov (United States)

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

    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 testing. Second, the result yields a simple set of…

  5. On the MIMO Capacity for Distributed System under Composite Rayleigh/Rician Fading and Shadowing

    Directory of Open Access Journals (Sweden)

    Santiago González-Aurioles

    2015-01-01

    Full Text Available Wireless channels are commonly affected by short-term fading and long-term fading (shadowing. The shadowing effects must be taken into account also when mobility is present in the wireless scenario. Using a composite fading model, the total channel capacity can be studied for a scenario with short-term Rayleigh fading along with shadowing. This work provides quantitative results for these kinds of scenarios with Rayleigh fading and shadowing, considering also multiple-input and multiple-output systems, which have not been previously reported. In addition, the channel capacity has been studied in depth in its relation with the shadowing level, signal to noise ratio, and the number of elements in the multiple-input and multiple-output system. Moreover, the channel performance with shadowing has been compared to the one without it. Furthermore, Rician model with shadowing is studied and its results are reported. In addition, correlated and experimental results are provided. It is identified that the distributed MIMO systems can benefit from shadowing in Rician channels. This advantage has not been reported previously. This type of fading is proposed for massive MIMO by others and our results open the door to emulate massive MIMO on a reverberation chamber.

  6. 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…

  7. 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…

  8. Performance analysis of a modified moving shadow elimination method developed for indoor scene activity tracking

    Science.gov (United States)

    Mitra, Bhargav Kumar; Fiaz, Muhammad Kamran; Kypraios, Ioannis; Birch, Philip; Young, Rupert; Chatwin, Chris

    2008-10-01

    Moving shadow detection is an important step in automated robust surveillance systems in which a dynamic object is to be segmented and tracked. Rejection of the shadow region significantly reduces the erroneous tracking of non-target objects within the scene. A method to eliminate such shadows in indoor video sequences has been developed by the authors. The objective has been met through the use of a pixel-wise shadow search process that utilizes a computational model in the RGB colour space to demarcate the moving shadow regions from the background scene and the foreground objects. However, it has been observed that the robustness and efficiency of the method can be significantly enhanced through the deployment of a binary-mask based shadow search process. This, in turn, calls for the use of a prior foreground object segmentation technique. The authors have also automated a standard foreground object segmentation technique through the deployment of some popular statistical outlier-detection based strategies. The paper analyses the performance i.e. the effectiveness as a shadow detector, discrimination potential, and the processing time of the modified moving shadow elimination method on the basis of some standard evaluation metrics.

  9. 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…

  10. The effect of shadow lines on a low concentrating photovoltaic system

    NARCIS (Netherlands)

    Janssen, H.J.J.; Sonneveld, P.J.; Swinkels, G.L.A.M.; Tuijl, van B.A.J.; Zwart, de H.F.

    2011-01-01

    In order to reduce the energy losses caused by shadow lines, three options are investigated. These are: 1. the use of two types of diodes; 2. the use of an ”ideal” diode based an active bypass by using MOS-FET’s [4] and 3. parallel switching of a number of cells between two shadow lines. The first

  11. Presence of Gumprecht shadows (smudge cells) in bovine leukemia virus-positive cattle.

    Science.gov (United States)

    Panei, Carlos Javier; Larsen, Alejandra; González, Ester Teresa; Echeverría, María Gabriela

    2013-11-01

    Enzootic Bovine Leukosis is a chronic disease caused by the bovine leukemia virus (BLV). Smudge cells, also known as Gumprecht shadows, are not simple artifacts of slide preparation, but ragged lymphoid cells found mainly in peripheral blood smears from human patients with chronic lymphocytic leukemia. In this study, we report the presence of Gumprecht shadows in peripheral blood from BLV-positive cattle.

  12. Automatic aerial image shadow detection through the hybrid analysis of RGB and HIS color space

    Science.gov (United States)

    Wu, Jun; Li, Huilin; Peng, Zhiyong

    2015-12-01

    This paper presents our research on automatic shadow detection from high-resolution aerial image through the hybrid analysis of RGB and HIS color space. To this end, the spectral characteristics of shadow are firstly discussed and three kinds of spectral components including the difference between normalized blue and normalized red component - BR, intensity and saturation components are selected as criterions to obtain initial segmentation of shadow region (called primary segmentation). After that, within the normalized RGB color space and HIS color space, the shadow region is extracted again (called auxiliary segmentation) using the OTSU operation, respectively. Finally, the primary segmentation and auxiliary segmentation are combined through a logical AND-connection operation to obtain reliable shadow region. In this step, small shadow areas are removed from combined shadow region and morphological algorithms are apply to fill small holes as well. The experimental results show that the proposed approach can effectively detect the shadow region from high-resolution aerial image and in high degree of automaton.

  13. Education under the shadow in Southern European countries. Implications for equity

    Directory of Open Access Journals (Sweden)

    Ariadne Runte-Geidel

    2015-06-01

    Full Text Available Nowadays most educational research focuses on formal education. However it is gradually recognizing the existence of a parallel education system that accompanies the formal system as if was its own shadow. The shadow education is a system based on the laws of the market, still poorly regulated and under-researched. This comparative study aims to determine the prevalence of shadow education in Spain and countries in its geographical and cultural context, also examine their implications in the different countries studied. Analyzes carried out show high rates of use of shadow education in all countries studied and similarities in the effects on social equity. The findings point to the need for regulation of the sector and infer about problems in formal systems as the possible cause of the high rates of shadow education are found.

  14. Double shadow of a regular phantom black hole as photons couple to Weyl tensor

    CERN Document Server

    Huang, Yang; Jing, Jiliang

    2016-01-01

    We have studied the shadow of a regular phantom black hole as photons couple to Weyl tensor. We find that the coupling yields that photons with different polarization directions propagate along different paths in the spacetime so that there exits double shadow for a black hole, which is quite different from that in the non-coupling case where only a single shadow emerges. The umbra of black hole increases with the phantom charge and decreases with the coupling strength. The dependence of the penumbra on the phantom charge and the coupling strength is converse to that of the umbra. Combining with the supermassive central object in our Galaxy, we estimated the shadow of the black hole as the photons couple to Weyl tensor. Our results show that the coupling brings richer behaviors of the propagation of coupled photon and the shadow of the black hole in the regular phantom black hole spacetime.

  15. 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.

  16. Probing Solar Magnetic Field with the "Cosmic-Ray Shadow" of the Sun

    CERN Document Server

    Amenomori, M; Chen, D; Chen, T L; Chen, W Y; Cui, S W; Danzengluobu,; Ding, L K; Feng, C F; Feng, Zhaoyang; Feng, Z Y; Gou, Q B; Guo, Y Q; Hakamada, K; He, H H; He, Z T; Hibino, K; Hotta, N; Hu, Haibing; Hu, H B; Huang, J; Jia, H Y; Jiang, L; Kajino, F; Kasahara, K; Katayose, Y; Kato, C; Kawata, K; Labaciren,; Le, G M; Li, A F; Li, H J; Li, W J; Liu, C; Liu, J S; Liu, M Y; Lu, H; Meng, X R; Mizutani, K; Munakata, K; Nanjo, H; Nishizawa, M; Ohnishi, M; Ohta, I; Onuma, H; Ozawa, S; Qian, X L; Qu, X B; Saito, T; Saito, T Y; Sakata, M; Sako, T K; Shao, J; Shibata, M; Shiomi, A; Shirai, T; Sugimoto, H; Takita, M; Tan, Y H; Tateyama, N; Torii, S; Tsuchiya, H; Udo, S; Wang, H; Wu, H R; Xue, L; Yamamoto, Y; Yang, Z; Yasue, S; Yuan, A F; Yuda, T; Zhai, L M; Zhang, H M; Zhang, J L; Zhang, X Y; Zhang, Y; Zhang, Yi; Zhang, Ying; Zhaxisangzhu,; Zhou, X X

    2013-01-01

    We report on a clear solar-cycle variation of the Sun's shadow in the 10 TeV cosmic-ray flux observed by the Tibet air shower array during a full solar cycle from 1996 to 2009. In order to clarify the physical implications of the observed solar cycle variation, we develop numerical simulations of the Sun's shadow, using the Potential Field Source Surface (PFSS) model and the Current Sheet Source Surface (CSSS) model for the coronal magnetic field. We find that the intensity deficit in the simulated Sun's shadow is very sensitive to the coronal magnetic field structure, and the observed variation of the Sun's shadow is better reproduced by the CSSS model. This is the first successful attempt to evaluate the coronal magnetic field models by using the Sun's shadow observed in the TeV cosmic-ray flux.

  17. Encountering the shadow in rites of passage: a study in activations.

    Science.gov (United States)

    Casement, Ann

    2003-02-01

    Jung's concept of the shadow is explored in this paper through his writings on its realization and assimilation in which he says the shadow may be experienced as the regressed and denied 'other self' in each individual. However, this is not the whole picture, and he also points to the fact that the shadow contains more than something merely negative. While in no way treating them as 'patients', the paper will also touch on the experience of the anthropologist, Bronislaw Malinowski, and the writer, Joseph Conrad, in their personal encounters with the shadow. All three encountered the shadow whilst going through rites of passage of their own and each owes much to the Romantic Movement. In this context, attention is directed to the writings of the philosopher and theologian, Johann Gottfried von Herder, who discovered a deeper understanding of his destiny in the course of a sea voyage.

  18. Krüppel Expression Levels Are Maintained through Compensatory Evolution of Shadow Enhancers

    Directory of Open Access Journals (Sweden)

    Zeba Wunderlich

    2015-09-01

    Full Text Available Many developmental genes are controlled by shadow enhancers—pairs of enhancers that drive overlapping expression patterns. We hypothesized that compensatory evolution can maintain the total expression of a gene, while individual shadow enhancers diverge between species. To test this hypothesis, we analyzed expression driven by orthologous pairs of shadow enhancers from Drosophila melanogaster, Drosophila yakuba, and Drosophila pseudoobscura that control expression of Krüppel, a transcription factor that patterns the anterior-posterior axis of blastoderm embryos. We found that the expression driven by the pair of enhancers is conserved between these three species, but expression levels driven by the individual enhancers are not. Using sequence analysis and experimental perturbation, we show that each shadow enhancer is regulated by different transcription factors. These results support the hypothesis that compensatory evolution can occur between shadow enhancers, which has implications for mechanistic and evolutionary studies of gene regulation.

  19. Shadowing effects in Newton’s law from compact extra dimensions

    Science.gov (United States)

    Kleidis, K.; Oikonomou, V. K.

    2016-10-01

    One problem that appears in theories with compact extra dimensions is the shadowing phenomenon, which makes it difficult to identify the topology and the geometry of the extra-dimensional manifold, if it exists. In this paper, we address this problem from the perspective of Newton’s law modifications caused by compact extra dimensions. After providing the modifications cause by some of the most phenomenologically interesting compact manifolds, we qualitatively study and compare the modifications that these manifolds cause to Newton’s law. As we demonstrate, the shadowing phenomenon persists in this approach too, and it seems that the shadowing phenomenon is grouped in “shadowing zones”. At these points, it is impossible to distinguish which compact space causes the modification of Newton’s law. However, away from the shadowing zones, the effects of the different compact manifolds are distinguishable. It is possible that these effects can be observed in the next generation of Newton’s law experiments.

  20. Impact of Physical Layer Jamming on Wireless Sensor Networks with Shadowing and Multicasting

    Directory of Open Access Journals (Sweden)

    Nischay Bahl

    2012-07-01

    Full Text Available This paper analyzes the impact of a physical layer jamming on the performance of wireless sensor networks by performing exhaustive comparative simulations using multicasting and by employing varying intensity of shadowing (constant and log normal. Comprehensive result analysis reveals that jamming drastically degrades the legitimate traffic throughput in a network, and, the constant shadowing approach is a better fit for a static network, both, under static as well as mobile jammer environments, as compared to the log normal one. An improvement in sink-node packet delivery ratio by 15.02 % and 16.58 % was observed with static and mobile jammer environments respectively, under multicasting and constant shadowing mean of 8.0. Further, average sink-node packet delivery ratio with constant shadowing shows an improvement of 4.15% and 5.94%, using static and mobile jammer environment respectively, in comparison to the values obtained under log normal shadowing based network.

  1. Uniformity Masks Design Method Based on the Shadow Matrix for Coating Materials with Different Condensation Characteristics

    Directory of Open Access Journals (Sweden)

    Lichao Zhang

    2013-01-01

    Full Text Available An intuitionistic method is proposed to design shadow masks to achieve thickness profile control for evaporation coating processes. The proposed method is based on the concept of the shadow matrix, which is a matrix that contains coefficients that build quantitive relations between shape parameters of masks and shadow quantities of substrate directly. By using the shadow matrix, shape parameters of shadow masks could be derived simply by solving a matrix equation. Verification experiments were performed on a special case where coating materials have different condensation characteristics. By using the designed mask pair with complementary shapes, thickness uniformities of better than 98% are demonstrated for MgF2 ( and LaF3 ( simultaneously on a 280 mm diameter spherical substrate with the radius curvature of 200 mm.

  2. Krüppel Expression Levels Are Maintained through Compensatory Evolution of Shadow Enhancers.

    Science.gov (United States)

    Wunderlich, Zeba; Bragdon, Meghan D J; Vincent, Ben J; White, Jonathan A; Estrada, Javier; DePace, Angela H

    2015-09-22

    Many developmental genes are controlled by shadow enhancers—pairs of enhancers that drive overlapping expression patterns. We hypothesized that compensatory evolution can maintain the total expression of a gene, while individual shadow enhancers diverge between species. To test this hypothesis, we analyzed expression driven by orthologous pairs of shadow enhancers from Drosophila melanogaster, Drosophila yakuba, and Drosophila pseudoobscura that control expression of Krüppel, a transcription factor that patterns the anterior-posterior axis of blastoderm embryos. We found that the expression driven by the pair of enhancers is conserved between these three species, but expression levels driven by the individual enhancers are not. Using sequence analysis and experimental perturbation, we show that each shadow enhancer is regulated by different transcription factors. These results support the hypothesis that compensatory evolution can occur between shadow enhancers, which has implications for mechanistic and evolutionary studies of gene regulation.

  3. Locating the shadow regions in LIDAR data: results on the SHARE 2012 dataset

    Science.gov (United States)

    Boyaci, Mustafa; Yuksel, Seniha E.

    2015-05-01

    In hyperspectral imaging, shadowy areas present a major problem as targets in shadow show decreased or no spectral signatures. One way to mitigate this problem is by the fusion of hyperspectral data with LiDAR data; since LiDAR data presents excellent information by providing elevation information, which can then be used to identify the regions of shadow. Although there is a lot of work to detect the shadowy areas, many are restricted to distinct platforms like ARGCIS, ENVI etc. The purpose of this study is to (i) detect the shadow areas and to (ii) give a shadowiness scale in LiDAR data with Matlab in an efficient way. For this work, we designed our Line of Sight (LoS) algorithm that is optimized to run in a Matlab interface. The LoS algorithm uses the sun angles (altitude and azimuth) and elevation of the earth; and marks the pixel as "in shadow" if there lies an object of higher elevation between a given pixel and the sun. This is computed for all pixels in the scene and a shadow map is generated. Further, if a pixel is marked as a shadow area, the algorithm assigns a different darkness level which is inversely proportional to the distance between the current pixel and the object that causes the shadow. With this shadow scale, it is both visually and computationally possible to distinguish the soft shadows from the dark shadows; an important information for hyperspectral imagery. The algorithm has been tested on the SHARE 2012 Avon AM dataset. We also show the effect of the shadowiness scale on the spectral signatures.

  4. Modeling of global variations and ring shadowing in Saturn's ionosphere

    Science.gov (United States)

    Moore, L. E.; Mendillo, M.; Müller-Wodarg, I. C. F.; Murr, D. L.

    2004-12-01

    A time-dependent one-dimensional model of Saturn's ionosphere has been developed as an intermediate step towards a fully coupled Saturn Thermosphere-Ionosphere Model (STIM). A global circulation model (GCM) of the thermosphere provides the latitude and local time dependent neutral atmosphere, from which a globally varying ionosphere is calculated. Four ion species are used (H +, H +2, H +3, and He +) with current cross-sections and reaction rates, and the SOLAR2000 model for the Sun's irradiance. Occultation data from the Voyager photopolarimeter system (PPS) are adapted to model the radial profile of the ultraviolet (UV) optical depth of the rings. Diurnal electron density peak values and heights are generated for all latitudes and two seasons under solar minimum and solar maximum conditions, both with and without shadowing from the rings. Saturn's lower ionosphere is shown to be in photochemical equilibrium, whereas diffusive processes are important in the topside. In agreement with previous 1-D models, the ionosphere is dominated by H + and H +3, with a peak electron density of ˜10 electrons cm -3. At low- and mid-latitudes, H + is the dominant ion, and the electron density exhibits a diurnal maximum during the mid-afternoon. At higher latitudes and shadowed latitudes (smaller ionizing fluxes), the diurnal maximum retreats towards noon, and the ratio of [H +]/[H +3] decreases, with H +3 becoming the dominant ion at altitudes near the peak (˜1200-1600 km) for noon-time hours. Shadowing from the rings leads to attenuation of solar flux, the magnitude and latitudinal structure of which is seasonal. During solstice, the season for the Cassini spacecraft's encounter with Saturn, attenuation has a maximum of two orders of magnitude, causing a reduction in modeled peak electron densities and total electron column contents by as much as a factor of three. Calculations are performed that explore the parameter space for charge-exchange reactions of H + with

  5. Flavor Memory

    NARCIS (Netherlands)

    Mojet, Jos; Köster, Ep

    2016-01-01

    Odor, taste, texture, temperature, and pain all contribute to the perception and memory of food flavor. Flavor memory is also strongly linked to the situational aspects of previous encounters with the flavor, but does not depend on the precise recollection of its sensory features as in vision and

  6. Memory integration

    NARCIS (Netherlands)

    Sweegers, C.C.G.

    2014-01-01

    The aim of this thesis was to characterize the neural mechanisms underlying memory integration. In chapter 2, we studied the neural underpinnings of regularity extraction across hippocampus-dependent episodic memories. We found higher connectivity between the hippocampus and the mPFC for the

  7. Shared Memories?

    DEFF Research Database (Denmark)

    Wæhrens, Anne

    2011-01-01

    This paper analyses how the memory of the Holocaust has been addressed in the European Parliament from 1989 to 2009. I identify two major changes that occurred in the 1990s and after the 2004 enlargement of the European Union respectively. In the 1990s the war in Bosnia and the question of restit......This paper analyses how the memory of the Holocaust has been addressed in the European Parliament from 1989 to 2009. I identify two major changes that occurred in the 1990s and after the 2004 enlargement of the European Union respectively. In the 1990s the war in Bosnia and the question...... of restitution universalised the memory of the Holocaust and made it present. The 2004 enlargement brought the memory of Soviet Communism into the Union and made it a central task to construct a community of memory that includes both the memory of the Holocaust and of Soviet Communism. The analysis also...... identifies what seems to be a political memory split between Left and Right; and it shows that the time might not be ripe for a shared European memory....

  8. Collaging Memories

    Science.gov (United States)

    Wallach, Michele

    2011-01-01

    Even middle school students can have memories of their childhoods, of an earlier time. The art of Romare Bearden and the writings of Paul Auster can be used to introduce ideas about time and memory to students and inspire works of their own. Bearden is an exceptional role model for young artists, not only because of his astounding art, but also…

  9. Main Memory

    NARCIS (Netherlands)

    P.A. Boncz (Peter); L. Liu (Lei); M. Tamer Özsu

    2008-01-01

    htmlabstractPrimary storage, presently known as main memory, is the largest memory directly accessible to the CPU in the prevalent Von Neumann model and stores both data and instructions (program code). The CPU continuously reads instructions stored there and executes them. It is also called Random

  10. Memory conformity affects inaccurate memories more than accurate memories.

    Science.gov (United States)

    Wright, Daniel B; Villalba, Daniella K

    2012-01-01

    After controlling for initial confidence, inaccurate memories were shown to be more easily distorted than accurate memories. In two experiments groups of participants viewed 50 stimuli and were then presented with these stimuli plus 50 fillers. During this test phase participants reported their confidence that each stimulus was originally shown. This was followed by computer-generated responses from a bogus participant. After being exposed to this response participants again rated the confidence of their memory. The computer-generated responses systematically distorted participants' responses. Memory distortion depended on initial memory confidence, with uncertain memories being more malleable than confident memories. This effect was moderated by whether the participant's memory was initially accurate or inaccurate. Inaccurate memories were more malleable than accurate memories. The data were consistent with a model describing two types of memory (i.e., recollective and non-recollective memories), which differ in how susceptible these memories are to memory distortion.

  11. 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...

  12. Constipation is casting a shadow over everyday life

    DEFF Research Database (Denmark)

    Tvistholm, Nina; Munch, Lene; Kjærgaard Danielsen, Anne

    2017-01-01

    and four qualitative. Three main themes crystallised from the results of the included studies: bodily experiences, everyday life shadowed by constipation and adverse psychological effects. Conclusion Constipation among older people was connected to subjective and comprehensive experiences. It had....... Background Constipation is a common and overlooked problem with an impact on everyday life, especially among older people. Older people seem to have individual preconceptions on constipation which can influence the strategies used to prevent and treat constipation. Design A systematic review, integrating...... studies. Search terms included constipation, elderly, aged, elderly people, aged people, quality of life, patient experience, patient perspective, meaning, emotion, psychological. Reference lists were searched manually. Results A total of nine studies were included in the review, five quantitative...

  13. 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.

  14. Shadow enhancers enable Hunchback bifunctionality in the Drosophila embryo.

    Science.gov (United States)

    Staller, Max V; Vincent, Ben J; Bragdon, Meghan D J; Lydiard-Martin, Tara; Wunderlich, Zeba; Estrada, Javier; DePace, Angela H

    2015-01-20

    Hunchback (Hb) is a bifunctional transcription factor that activates and represses distinct enhancers. Here, we investigate the hypothesis that Hb can activate and repress the same enhancer. Computational models predicted that Hb bifunctionally regulates the even-skipped (eve) stripe 3+7 enhancer (eve3+7) in Drosophila blastoderm embryos. We measured and modeled eve expression at cellular resolution under multiple genetic perturbations and found that the eve3+7 enhancer could not explain endogenous eve stripe 7 behavior. Instead, we found that eve stripe 7 is controlled by two enhancers: the canonical eve3+7 and a sequence encompassing the minimal eve stripe 2 enhancer (eve2+7). Hb bifunctionally regulates eve stripe 7, but it executes these two activities on different pieces of regulatory DNA--it activates the eve2+7 enhancer and represses the eve3+7 enhancer. These two "shadow enhancers" use different regulatory logic to create the same pattern.

  15. Integrated Differential Optical Shadow Sensor for Modular Gravitational Reference Sensor

    CERN Document Server

    Zoellner, Andreas; Sun, Ke-Xun

    2013-01-01

    The Laser Interferometer Space Antenna (LISA) is a proposed space mission for the detection of gravitational waves. It consists of three drag-free satellites flying in a triangular constellation. A gravitational reference sensor is used in conjunction with a laser interferometer to measure the distance between test masses inside the three satellites. Other future space mission such as DECIGO and BBO also require a gravitational reference sensor. The Modular Gravitational Reference Sensor (MGRS) is being designed for these purposes and consists of two different optical sensors and a UV LED charge management system. The Differential Optical Shadow Sensor (DOSS) is one of the optical sensors and measures the position of a spherical test mass with respect to the surrounding satellite. This measurement is used for the drag-free feedback control loop. This paper describes the most recent, third generation of the experimental setup for the DOSS that uses a fiber coupled super luminescent LED, an integrated mounting ...

  16. Photoabsorption on nuclei in the shadowing threshold region

    CERN Document Server

    Muccifora, V; Deppman, A; De Sanctis, E; Mirazita, M; Polli, E; Rossi, P; Burgwinkel, R; Hannappel, J; Klein, F; Menze, D W; Schwille, W J; Wehnes, F

    1998-01-01

    The energy and nuclear mass dependences of the total hadronic cross section in the energy range 0.5-2.6 GeV have been measured at Bonn using the SAPHIR tagged photon beam. The measurement, performed on C, Al, Cu, Sn and Pb, provides the first photoabsorption data in the region 1.2-1.7 GeV. The results show a significant reduction of the photoabsorption strength on the bound nucleon compared to the free nucleon case in the whole energy region. Above 1.2 GeV this reduction decreases with the nuclear density and can be interpreted as a signature of a low energy onset of the shadowing effect.

  17. 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.

  18. Frustum-Traced Irregular Z-Buffers: Fast, Sub-pixel Accurate Hard Shadows.

    Science.gov (United States)

    Wyman, Chris; Hoetzlein, Rama; Lefohn, Aaron

    2016-05-25

    We further describe and analyze a real-time system for rendering antialiased hard shadows using irregular z-buffers (IZBs) that we first presented in Wyman et al. [1]. We focus on identifying bottlenecks, exploring these from an algorithmic complexity standpoint, and presenting techniques to improve performance. Our system remains interactive on a variety of game assets and CAD models while running at resolutions 1920 1080 and above and imposes no constraints on light, camera or geometry, allowing fully dynamic scenes without precomputation. We render sub-pixel accurate, 32 sample per pixel hard shadows at roughly twice the cost of a single sample per pixel. This allows us to smoothly animate even subpixel shadows from grass or wires without introducing spatial or temporal aliasing. Prior algorithms for irregular z-buffer shadows rely heavily on the GPU's compute pipeline. Instead we leverage the standard rasterization-based graphics pipeline, including hardware conservative raster and early-z culling. Our key observation is noting a duality between irregular z-buffer performance and shadow map quality; irregular z-buffering is most costly exactly where shadow maps exhibit the worst aliasing. This allows us to use common shadow map algorithms, which typically improve aliasing, to instead reduce our cost. Compared to state of the art ray tracers, we spawn similar numbers of triangle intersections per pixel yet completely rebuild our data structure in under 1 ms per frame.

  19. 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.

  20. 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...

  1. Shadow cast by a Kaluza-Klein spinning dilaton black hole

    CERN Document Server

    Amarilla, Leonardo

    2015-01-01

    We examine the shadow of a rotating Kaluza-Klein black hole in Einstein gravity coupled to a Maxwell field and a dilaton. The size and the shape of the shadow depend on the mass, the charge, and the angular momentum of the compact object. For a given mass, the size increases with the rotation parameter and decreases with the electric charge. The distortion with respect to the non rotating case grows with the charge and the rotation parameter. For fixed values of these parameters, the shadow is slightly larger and less deformed than in the Kerr-Newman case.

  2. Possible imprints of cosmic strings in the shadows of galactic black holes

    CERN Document Server

    Tinchev, Vassil K

    2013-01-01

    We examine the shadow cast by the Kerr black hole pierced by a cosmic string. The observable images depend not only on the black hole spin parameter and the angle of inclination, but also on the deficit angle yielded by the cosmic string. The dependence of the observable characteristics of the shadow on the deficit angle is explored. The imprints in the black hole shadow left by the presence of a cosmic string can serve as method for observational detection of the cosmic strings.

  3. 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...

  4. 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.

  5. Metal-Insulator Transition of Solid Hydrogen by the Antisymmetric Shadow Wave Function

    CERN Document Server

    Calcavecchia, Francesco

    2016-01-01

    We present an improved shadow wave function approach to quantum Monte Carlo for large-scale fermionic systems. It is based on employing the antisymmetric shadow wave function in conjunction with the Gaussian determinant method to reduce the variance and an enhanced stochastic reconfiguration scheme to efficiently optimize the trail wave function, as well as refined twist averaged boundary conditions and periodic coordinates techniques. The predictive power of this approach is demonstrated by revisiting the pressure-induced metal-insulator-transition of solid hydrogen. It is found that the ameliorated accuracy of the antisymmetric shadow wave function results in a significantly increased transition pressure.

  6. Memory loss

    Science.gov (United States)

    A person with memory loss needs a lot of support. It helps to show the person familiar objects, music, or and photos or play familiar music. Write down when the person should take any medicine or do other ...

  7. 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

  8. Memory clinics

    OpenAIRE

    Jolley, D; Benbow, S M; Grizzell, M

    2006-01-01

    Memory clinics were first described in the 1980s. They have become accepted worldwide as useful vehicles for improving practice in the identification, investigation, and treatment of memory disorders, including dementia. They are provided in various settings, the setting determining clientele and practice. All aim to facilitate referral from GPs, other specialists, or by self referral, in the early stages of impairment, and to avoid the stigma associated with psychiatric services. They bring ...

  9. THE OBJECTIFICATION OF DEFINITION OF THE PURCHASING POWER OF CONSUMERS IN SHADOW ECONOMY

    National Research Council Canada - National Science Library

    Tyukhtenko, N; Makarenko, S; Oliynik, N

    2016-01-01

    .... Proposed the method of calculating the correction coefficient with a view to determining the level of objectification purchasing power of consumers in a shadow economy and the potential capacity...

  10. Leading twist nuclear shadowing, nuclear generalized parton distributions and nuclear DVCS at small x

    Energy Technology Data Exchange (ETDEWEB)

    Guzey, Vadim; Goeke, Klaus; Siddikov, Marat

    2009-01-01

    We generalize the leading twist theory of nuclear shadowing and calculate quark and gluon generalized parton distributions (GPDs) of spinless nuclei. We predict very large nuclear shadowing for nuclear GPDs. In the limit of the purely transverse momentum transfer, our nuclear GPDs become impact parameter dependent nuclear parton distributions (PDFs). Nuclear shadowing induces non-trivial correlations between the impact parameter $b$ and the light-cone fraction $x$. We make predictions for the deeply virtual Compton scattering (DVCS) amplitude and the DVCS cross section on $^{208}$Pb at high energies. We calculate the cross section of the Bethe-Heitler (BH) process and address the issue of the extraction of the DVCS signal from the $e A \\to e \\gamma A$ cross section. We find that the $e A \\to e \\gamma A$ differential cross section is dominated by DVCS at the momentum transfer $t$ near the minima of the nuclear form factor. We also find that nuclear shadowing leads

  11. The Close Objects Buffer : A Sharp Shadow Detection Technique for Radiosity Methods

    NARCIS (Netherlands)

    Telea, A.C.; Overveld, C.W.A.M. van

    1998-01-01

    Detecting sharp illumination variations such as shadow boundaries is an important problem for radiosity methods. Such illumination variations are captured using a nonuniform mesh that refines the areas exhibiting high illumination gradients. Nonuniform meshing techniques like discontinuity meshing o

  12. 77 FR 39319 - Culturally Significant Objects Imported for Exhibition Determinations: “Bodies and Shadows...

    Science.gov (United States)

    2012-07-02

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF STATE Culturally Significant Objects Imported for Exhibition Determinations: ``Bodies and Shadows: Caravaggio and...: Caravaggio and His Legacy'' imported from abroad for temporary exhibition within the United States, are...

  13. Book review: Confronting the Shadow Education System: What Government Policies for What Private Tutoring'

    Directory of Open Access Journals (Sweden)

    Keith Watson

    2012-10-01

    Full Text Available Book Review Confronting the Shadow Education System: What Government Policies for What Private Tutoring' By Mark Bray (2009, 135pp. ISBN: 078-92-803-1333-8, Paris: IIEP/UNESCO Publishing

  14. Reduction of implantation shadowing effect by dual-wavelength exposure photo process

    CERN Document Server

    Gu, Yiming; Lee Sang Yun; Roche, William; Sturtevant, John

    2003-01-01

    As transistor engineering continues to well below 100 nm length devices, ion implantation process tolerances are making these formerly "non-critical" lithography levels more and more difficult. In order to minimize the channeling effect and to obtain a controllable profile of dopant, an angle implantation is often required. However, a shadow area of resist pattern is always accompanied with an angle implantation. This shadowing effect consumes silicon real estate, and reduces the line edge placement (LEP) tolerances. Therefore, methodologies to reduce the shadowing effect in angled implantation become a critical consideration not only for device engineering but also for photolithography. Based on the model analysis, simulation and experiments, this paper presents an effective novel process utilizing dual-wavelength exposure (DWE) to reduce the shadowing effect. The DWE process is realized by two consecutive exposures for an I-line resist with a DUV stepper/scanner and an I-line stepper. The process leverages ...

  15. The effects of shadow removal on across-date settlement type classification of quickbird images

    CSIR Research Space (South Africa)

    Luus, FPS

    2012-07-01

    Full Text Available QuickBird imagery acquired on separate dates may have significant differences in viewing- and illumination geometries, which can negatively impact across-date settlement type classification accuracy. The effect of cast shadows on classification...

  16. SHADOW ECONOMY AND ITS RELATIONS WITH TAX SYSTEM, BUDGET DEFICIT AND MACROECONOMIC INDICATORS

    Directory of Open Access Journals (Sweden)

    I. Savych

    2015-03-01

    Full Text Available The paper analyzes the influence of the shadow economy on the tax system, state budget and a number of macroeconomic parameters of Ukraine such as poverty, income levels, corruption, GDP per capita, public debt, budget violations etc. The results of our research show that level of corruption, monopolization and budget violations are considered key factors that stimulate the shadowing of the economy. On the other hand, a number of researchers state that the average wage level is a strong destimulating factor for the shadow economy. The analysis given uncovers a robust relationship between the corruption and the size of the shadow economy when perceptions-based indices of corruption are used.

  17. The X-ray shadow of the high-latitude molecular cloud MBM 12

    Science.gov (United States)

    Snowden, S. L.; Mccammon, D.; Verter, F.

    1993-01-01

    ROSAT XRT/PSPC observations show a deep shadow cast by the high-latitude molecular cloud MBM 12 in the 3/4 keV diffuse background. Modeling of the shadow implies that less than 20 percent of the typical high-latitude 3/4 keV diffuse background intensity is emitted in front of the cloud (D = 60-70 pc). A weaker shadow consistent with the lower optical depth at higher energies was observed in the 1.5 keV band. Since little shadowing was seen in the 1/4 keV band, this observation places strong constraints on the amount of 0.5-2 keV emission that is intermixed with the source of the observed 1/4 keV flux.

  18. Rough surfaces: Is the dark stuff just shadow?. ;Who knows what evil lurks in the hearts of men? The shadow knows!;☆

    Science.gov (United States)

    Cuzzi, Jeffrey N.; Chambers, Lindsey B.; Hendrix, Amanda R.

    2017-06-01

    Remote observations of the surfaces of airless planetary objects are fundamental to inferring the physical structure and compositional makeup of the surface material. A number of forward models have been developed to reproduce the photometric behavior of these surfaces, based on specific, assumed structural properties such as macroscopic roughness and associated shadowing. Most work of this type is applied to geometric albedos, which are affected by complicated effects near zero phase angle that represent only a tiny fraction of the net energy reflected by the object. Other applications include parameter fits to resolved portions of some planetary surface as viewed over a range of geometries. The spherical albedo of the entire object (when it can be determined) captures the net energy balance of the particle more robustly than the geometric albedo. In most treatments involving spherical albedos, spherical albedos and particle phase functions are often treated as if they are independent, neglecting the effects of roughness. In this paper we take a different approach. We note that whatever function captures the phase angle dependence of the brightness of a realistic rough, shadowed, flat surface element relative to that of a smooth granular surface of the same material, it is manifested directly in both the integral phase function and the spherical albedo of the object. We suggest that, where broad phase angle coverage is possible, spherical albedos may be easily corrected for the effects of shadowing using observed (or assumed) phase functions, and then modeled more robustly using smooth-surface regolith radiative transfer models without further imposed (forward-modeled) shadowing corrections. Our approach attributes observed ;powerlaw; phase functions of various slope (and ;linear; ranges of magnitude-vs.-phase angle) to shadowing, as have others, and goes in to suggest that regolith-model-based inferences of composition based on shadow-uncorrected spherical

  19. Production structure and Cost efficiency of irrigated agriculture: A shadow cost approach

    OpenAIRE

    Zaibet, L.; Salah Bachta, Mohamed; Ben Salem, H.

    2005-01-01

    International audience; The improvement of irrigated agriculture needs sound performance assessment based on economic principles. This is particularly relevant to design adequate policies in terms of water allocation. In this paper we endeavour to assess irrigation efficiency using a behavioural approach in which the cost function (shadow cost) is based on shadow prices of inputs. This approach is useful to derive price distortion coefficients to indicate the level of allocative efficiency in...

  20. Activation of the Human MT Complex by Motion in Depth Induced by a Moving Cast Shadow.

    Science.gov (United States)

    Katsuyama, Narumi; Usui, Nobuo; Taira, Masato

    2016-01-01

    A moving cast shadow is a powerful monocular depth cue for motion perception in depth. For example, when a cast shadow moves away from or toward an object in a two-dimensional plane, the object appears to move toward or away from the observer in depth, respectively, whereas the size and position of the object are constant. Although the cortical mechanisms underlying motion perception in depth by cast shadow are unknown, the human MT complex (hMT+) is likely involved in the process, as it is sensitive to motion in depth represented by binocular depth cues. In the present study, we examined this possibility by using a functional magnetic resonance imaging (fMRI) technique. First, we identified the cortical regions sensitive to the motion of a square in depth represented via binocular disparity. Consistent with previous studies, we observed significant activation in the bilateral hMT+, and defined functional regions of interest (ROIs) there. We then investigated the activity of the ROIs during observation of the following stimuli: 1) a central square that appeared to move back and forth via a moving cast shadow (mCS); 2) a segmented and scrambled cast shadow presented beside the square (sCS); and 3) no cast shadow (nCS). Participants perceived motion of the square in depth in the mCS condition only. The activity of the hMT+ was significantly higher in the mCS compared with the sCS and nCS conditions. Moreover, the hMT+ was activated equally in both hemispheres in the mCS condition, despite presentation of the cast shadow in the bottom-right quadrant of the stimulus. Perception of the square moving in depth across visual hemifields may be reflected in the bilateral activation of the hMT+. We concluded that the hMT+ is involved in motion perception in depth induced by moving cast shadow and by binocular disparity.

  1. The movement of shadows: a teaching proposal for the secondary school

    OpenAIRE

    Gangui, Alejandro; Iglesias, Maria; Quinteros, Cynthia

    2009-01-01

    A didactic sequence of activities on some topics of Astronomy, related mainly with the length and orientation of shadows cast by a gnomon, the movement of shadows during daytime in different seasons of the year, and finding the true astronomical North, is fully developed. It also includes a discussion of observations from different frames of reference and of some topics in the history of science to enrich a debate among students, as well as the construction of a simplified model for the appar...

  2. Simplified Least Squares Shadowing sensitivity analysis for chaotic ODEs and PDEs

    Energy Technology Data Exchange (ETDEWEB)

    Chater, Mario, E-mail: chaterm@mit.edu; Ni, Angxiu, E-mail: niangxiu@mit.edu; Wang, Qiqi, E-mail: qiqi@mit.edu

    2017-01-15

    This paper develops a variant of the Least Squares Shadowing (LSS) method, which has successfully computed the derivative for several chaotic ODEs and PDEs. The development in this paper aims to simplify Least Squares Shadowing method by improving how time dilation is treated. Instead of adding an explicit time dilation term as in the original method, the new variant uses windowing, which can be more efficient and simpler to implement, especially for PDEs.

  3. Vampirism as a Shadow in Bram Stoker’s Dracula

    Directory of Open Access Journals (Sweden)

    Yujin Jang

    2014-12-01

    Full Text Available Through the studies of literal and metaphorical meanings of eating in Bram Stoker’s Dracula (1897, this article investigates how the depictions of food and eating culture in Transylvania are the results of misrepresentations. Contrast to the illustrations about the consumptions of food in the Western table which accompanies the spirit of unity, the predatory images of vampires in Transylvania can be easily associated with an idea that communion is absent in the foreign land. The purpose of this article is, thus, to subvert the binary oppositions between East and West, with the focus on the descriptions of food and eating. For this goal, the examinations in this article include: three female vampires’ language which involves the sense of communion, the Western characters’ eating at a table which turns out to be a defective place in achieving the spirit of unity, and a lunatic character R.M. Renfield’s abnormal eating habits that can be interpreted within the contemporary socioeconomic contexts. Ultimately, this article is to show how the vampiric images in Stoker’s Dracula function as shadows that cover the violence of the Western middle-class capitalists in the contemporary capital-oriented society.

  4. Observing The Cosmic Ray Moon Shadow With VERITAS

    CERN Document Server

    Bird, Ralph

    2015-01-01

    The Earth is subjected to a uniform flux of very-high-energy (VHE, E > 100 GeV) cosmic rays unless they are obscured by an object, such as the Moon, in which case a deficit or shadow is created. Since cosmic rays are charged this deficit is deflected by the Earth's magnetic field, enabling the rigidity of the obstructed cosmic rays to be determined. Measurement of the relative deficits of different species enables the positron fraction and the antiproton ratio to be measured. The April 15, 2014 lunar eclipse was visible with the VERITAS Cherenkov telescopes, which allowed (with special UV bandpass filters) 74 minutes of direct observations of the Moon and the associated deficit in the cosmic-ray flux. The results of this observation are presented. In addition VERITAS has been conducting a series of observations by pointing close to a partially illuminated Moon, with a reduced photomultiplier tube high voltage and UV bandpass filters. We present the technique developed for these observations and their current ...

  5. Current treatment of antiphospholipid syndrome: lights and shadows.

    Science.gov (United States)

    Espinosa, Gerard; Cervera, Ricard

    2015-10-01

    For patients with antiphospholipid syndrome (APS), the consensus is to treat those who develop thrombosis with long-term oral anticoagulation therapy and to prevent obstetric manifestations by use of aspirin and heparin. These recommendations are based on data from randomized controlled trials and observational studies. Despite this body of knowledge, areas of uncertainty regarding the management of APS exist where evidence is scarce or nonexistent. In other words, for a subset of patients the course of management is unclear. Some examples are patients with 'seronegative' APS, those who do not fulfil the formal (clinical or serological) classification criteria for definite APS, and those with recurrent thrombotic events despite optimal anticoagulation. Other challenges include the treatment of clinical manifestations not included in the classification criteria, such as haematologic manifestations (thrombocytopenia and haemolytic anaemia), neurologic manifestations (chorea, myelitis and multiple sclerosis-like lesions), and nephropathy and heart valve disease associated with antiphospholipid antibodies (aPL), as well as the possible withdrawal of anticoagulation treatment in selected cases of thrombotic APS in which assays for aPL become persistently negative. This Review focuses on the current recommendations for thrombotic and obstetric manifestations of APS, as well as the management of difficult cases. Some aspects of treatment, such as secondary prophylaxis of venous thrombosis, are based on strong evidence--the 'lights' of APS treatment. Conversely, other areas, such as the treatment of non-criteria manifestations of APS, are based only on expert consensus or common sense and remain the 'shadows' of APS therapy.

  6. Shadows cast on the transition disk of HD 135344B

    CERN Document Server

    Stolker, T; Avenhaus, H; Min, M; de Boer, J; Ginski, C; Schmid, H M; Juhasz, A; Bazzon, A; Waters, L B F M; Garufi, A; Augereau, J -C; Benisty, M; Boccaletti, A; Henning, Th; Maire, A -L; Menard, F; Meyer, M R; Langlois, M; Pinte, C; Quanz, S P; Thalmann, C; Beuzit, J -L; Carbillet, M; Costille, A; Dohlen, K; Feldt, M; Gisler, D; Mouillet, D; Pavlov, A; Perret, D; Petit, C; Pragt, J; Rochat, S; Roelfsema, R; Salasnich, B; Soenke, C; Wildi, F

    2016-01-01

    The protoplanetary disk of the F-type star HD 135344B (SAO 206462) is in a transition stage and shows many intriguing structures both in scattered light and thermal millimeter emission which are possibly related to planet formation processes and planet-disk interactions. We have carried out high-contrast polarimetric differential imaging (PDI) observations with VLT/SPHERE and obtained the first optical polarized scattered light images with the sub-instrument ZIMPOL in R- and I-band. Additionally, near-infrared polarimetric observations were done with IRDIS in Y- and J-band. We will use the scattered light images, surface brightness profiles and color to study in detail disk structures and brightness variations. The scattered light images reveal with unprecedented sensitivity and angular resolution the spiral arm structure of the disk as well as the inner disk cavity of 25 au in all filters. Multiple shadow features are discovered on the outer disk and the observations of the two epochs show indications of var...

  7. Shadow Prices of Selected Agricultural Commodities – The Czech Case

    Directory of Open Access Journals (Sweden)

    Patrik Sieber

    2016-10-01

    Full Text Available The main objective of the paper is to contribute to practical applicability of the CBA in the agricultural sector by exploring the chances to estimate Czech social values of selected agricultural commodities using available statistical data. More specifically, we try to analyse for which commodities secondary data sets are available from which we may deduce the estimates of shadow price ratios, then to estimate SPRs for selected agricultural commodities and to analyse and discuss the applicability of such estimates in practical appraisal with respect to theoretically ideal measures and resulting available measures as well as with respect to the situation in which the CBA analyst typically is. We selected the following commodities: poultry, pigs, bulls, milk, rapeseed, maize, barley and wheat as items more suitable for SPR estimates mostly because of the data availability and the internal homogeneity of the items, which was closer to the theoretically required values than for other commodities. Under additional simplifying assumptions, we estimated SPR proxies for the particular commodities and finally summarized the pros and cons for application of SPR alternatives.

  8. Memory consolidation.

    Science.gov (United States)

    Squire, Larry R; Genzel, Lisa; Wixted, John T; Morris, Richard G

    2015-08-03

    Conscious memory for a new experience is initially dependent on information stored in both the hippocampus and neocortex. Systems consolidation is the process by which the hippocampus guides the reorganization of the information stored in the neocortex such that it eventually becomes independent of the hippocampus. Early evidence for systems consolidation was provided by studies of retrograde amnesia, which found that damage to the hippocampus-impaired memories formed in the recent past, but typically spared memories formed in the more remote past. Systems consolidation has been found to occur for both episodic and semantic memories and for both spatial and nonspatial memories, although empirical inconsistencies and theoretical disagreements remain about these issues. Recent work has begun to characterize the neural mechanisms that underlie the dialogue between the hippocampus and neocortex (e.g., "neural replay," which occurs during sharp wave ripple activity). New work has also identified variables, such as the amount of preexisting knowledge, that affect the rate of consolidation. The increasing use of molecular genetic tools (e.g., optogenetics) can be expected to further improve understanding of the neural mechanisms underlying consolidation. Copyright © 2015 Cold Spring Harbor Laboratory Press; all rights reserved.

  9. Is external memory memory? Biological memory and extended mind.

    Science.gov (United States)

    Michaelian, Kourken

    2012-09-01

    Clark and Chalmers (1998) claim that an external resource satisfying the following criteria counts as a memory: (1) the agent has constant access to the resource; (2) the information in the resource is directly available; (3) retrieved information is automatically endorsed; (4) information is stored as a consequence of past endorsement. Research on forgetting and metamemory shows that most of these criteria are not satisfied by biological memory, so they are inadequate. More psychologically realistic criteria generate a similar classification of standard putative external memories, but the criteria still do not capture the function of memory. An adequate account of memory function, compatible with its evolution and its roles in prospection and imagination, suggests that external memory performs a function not performed by biological memory systems. External memory is thus not memory. This has implications for: extended mind theorizing, ecological validity of memory research, the causal theory of memory.

  10. Double shadow of a regular phantom black hole as photons couple to the Weyl tensor

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Yang; Chen, Songbai; Jing, Jiliang [Hunan Normal University, Institute of Physics and Department of Physics, Changsha, Hunan (China); Hunan Normal University, Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Education, Changsha, Hunan (China); Hunan Normal University, Synergetic Innovation Center for Quantum Effects and Applications, Changsha, Hunan (China)

    2016-11-15

    We have studied the shadow of a regular phantom black hole as photons couple to the Weyl tensor. We find that due to the coupling photons with different polarization directions propagate along different paths in the spacetime so that there exists a double shadow for a black hole, which is quite different from that in the non-coupling case where only a single shadow emerges. The overlap region of the double shadow, the umbra, of the black hole increases with the phantom charge and decreases with the coupling strength. The dependence of the penumbra on the phantom charge and the coupling strength is converse to that of the umbra. Combining with the supermassive central object in our Galaxy, we estimated the shadow of the black hole as the photons couple to the Weyl tensor. Our results show that the coupling brings about richer behaviors of the propagation of coupled photon and the shadow of the black hole in the regular phantom black hole spacetime. (orig.)

  11. A New Index to Perform Shadow Detection in GeoEye-1 Images

    Directory of Open Access Journals (Sweden)

    Claudio Meneghini

    2015-10-01

    Full Text Available With the introduction of new satellites for earth monitoring characterized by very high resolution (VHR sensors, new algorithms to recognize shadow in the supplied images are necessary. Automatic shadow detection can enhance the interpretability of the images in several applications such as classification and change detection. Several approaches are present in literature for shadow detection and their adaptation and particularization for VHR satellite images are still in evolution. The goal of this paper is to propose a new index for shadow detection based on multispectral files processing. GeoEye-1 satellite data are used for this study: IHS pan-sharpening method is applied to transfer pixel dimensions of the panchromatic image (spatial resolution: 0.5 m x 0.5 m into the multispectral images (2 m x 2 m; an index named ERGAS is used to test the quality of the resulting raster files. Dealing with the problem of the shadow detection, a new index is defined to identify the affected pixels both in the original as well as pan-sharpened images. The results are compared with them by another index named ratio that is generally applied for shadow detection in multispectral images: issues and advantages, derived by using the proposed technique, are discussed.

  12. The Relation of Shadow Systems and ERP Systems—Insights from a Multiple-Case Study

    Directory of Open Access Journals (Sweden)

    Melanie Huber

    2016-01-01

    Full Text Available ERP systems integrate a major part of all business processes and organizations include them in their IT service management. Besides these formal systems, there are additional systems that are rather stand-alone and not included in the IT management tasks. These so-called ‘shadow systems’ also support business processes but hinder a high enterprise integration. Shadow systems appear during their explicit detection or during software maintenance projects such as enhancements or release changes of enterprise systems. Organizations then have to decide if and to what extent they integrate the identified shadow systems into their ERP systems. For this decision, organizations have to compare the capabilities of each identified shadow system with their ERP systems. Based on multiple-case studies, we provide a dependency approach to enable their comparison. We derive categories for different stages of the dependency and base insights into integration possibilities on these stages. Our results show that 64% of the shadow systems in our case studies are related to ERP systems. This means that they share parts or all of their data and/or functionality with the ERP system. Our research contributes to the field of integration as well as to the discussion about shadow systems.

  13. A coordinate-independent characterization of a black-hole shadow

    CERN Document Server

    Abdujabbarov, A A; Ahmedov, B J

    2015-01-01

    A large international effort is under way to assess the presence of a shadow in the radio emission from the compact source at the center of our galaxy, Sagittarius A$^*$ (Sgr A$^*$). If detected, this shadow would provide the first direct evidence of the existence of black holes and that Sgr A$^*$ is a supermassive black hole. In addition, the shape of the shadow could be used to learn about extreme gravity near the event horizon and to determine which theory of gravity better describes the observations. The mathematical description of the shadow has so far used a number of simplifying assumptions that are unlikely to be met by the real observational data. We here provide a general formalism to describe the shadow as an arbitrary polar curve expressed in terms of a Legendre expansion. Our formalism does not presume any knowledge of the properties of the shadow, e.g., the location of its center, and offers a number of routes to characterize the distortions of the curve with respect to reference circles. These ...

  14. Impact of ground mover motion and windowing on stationary and moving shadows in synthetic aperture radar imagery

    Science.gov (United States)

    Miller, J.; Bishop, E.; Doerry, A.; Raynal, A. M.

    2015-05-01

    This paper describes the impact of ground mover motion and windowing on stationary and moving shadows in Synthetic Aperture Radar (SAR) and video SAR mode imagery. The technique provides a foundation for optimizing algorithms that detect ground movers in SAR imagery. The video SAR mode provides a persistent view of a scene centered at the Motion Compensation Point (MCP). The radar platform follows a circular flight path. Detecting a stationary shadow in a SAR image is important because the shadow indicates a detection of an object with a height component near the shadow. Similarly, the detection of a shadow that moves from frame to frame indicates the detection of a ground mover at the location of the moving shadow. An approach analyzes the impact of windowing in calculating the brightness of a pixel in a stationary, finite-sized shadow region. An extension of the approach describes the pixel brightness for a moving shadow as a function of its velocity. The pixel brightness provides an upper bound on the Probability of Detection (PD) and a lower bound on the Probability of False Alarm (PFA) for a finite-sized, stationary or moving shadow in the presence of homogeneous, ideal clutter. Synthetic data provides shadow characteristics for a radar scenario that lend themselves for detecting a ground mover. The paper presents 2011-2014 flight data collected by General Atomics Aeronautical Systems, Inc. (GA-ASI).

  15. Memory training in depression

    NARCIS (Netherlands)

    Becker, E.S.; Vanderhasselt, M.A.; Vrijsen, J.N.

    2015-01-01

    Memory biases, that is, general memory impairments as well as specific mood-congruent memory biases, are important vulnerability factors in depression. Recently, computerized memory trainings have been developed to target these biases, reducing rumination and lightening depressive symptoms. This

  16. Mother-Blaming in the Shadow of Incest: Commentary on "Motherhood in the Shadow of Incest" by Rachel Lev-Wiesel

    Science.gov (United States)

    Faller, Kathleen Coulborn

    2007-01-01

    This commentary on "Motherhood in the Shadow of Incest" by Rachel Lev-Wiesel, is divided into three sections. In the first section, this author addresses the issue of the role of mothers in incest. Faller contends that, with regard to research findings on the role of mothers' own sexual victimization in her child's experience, previous research…

  17. Anticipated Electrical Environment Within Permanently Shadowed Lunar Craters

    Science.gov (United States)

    Farrell, W. M.; Stubbs, T. J.; Halekas, J. S.; Killen, R. M.; Delory, G. T.; Collier, M. R.; Vondrak, R. R.

    2010-01-01

    Shadowed locations ncar the lunar poles arc almost certainly electrically complex regions. At these locations near the terminator, the local solar wind flows nearly tangential to the surface and interacts with large-scale topographic features such as mountains and deep large craters, In this work, we study the solar wind orographic effects from topographic obstructions along a rough lunar surface, On the leeward side of large obstructions, plasma voids are formed in the solar wind because of the absorption of plasma on the upstream surface of these obstacles, Solar wind plasma expands into such voids) producing an ambipolar potential that diverts ion flow into the void region. A surface potential is established on these leeward surfaces in order to balance the currents from the expansion-limited electron and ion populations, Wc find that there arc regions ncar the leeward wall of the craters and leeward mountain faces where solar wind ions cannot access the surface, leaving an electron-rich plasma previously identified as an "electron cloud." In this case, some new current is required to complete the closure for current balance at the surface, and we propose herein that lofted negatively charged dust is one possible (nonunique) compensating current source. Given models for both ambipolar and surface plasma processes, we consider the electrical environment around the large topographic features of the south pole (including Shoemaker crater and the highly varied terrain near Nobile crater), as derived from Goldstone radar data, We also apply our model to moving and stationary objects of differing compositions located on the surface and consider the impact of the deflected ion flow on possible hydrogen resources within the craters

  18. Investigating shadows: a pedagogical intervention project with primary school children

    Science.gov (United States)

    Noversa, Silvana; Abreu, Cátia; Varela, Paulo; Costa, Manuel F. M.

    2014-07-01

    This communication results from a pedagogical intervention project, carried out at a primary school in the district of Braga - Portugal. The intervention took place in a class of the 3rd year, composed of 16 students, and it incorporated the practice of inquiry-based science teaching addressing the theme "Light Experiments", which is part of the "Environmental Studies" curricular area. Various class activities were planned and implemented concerning some of the factors that influence the shadow of an object, in order to find answers to the following three questions: a) will 3rd year students, aged 7/8 years, be able to construct and execute an investigation strategy that involves manipulating and controlling variables? b) what are the main difficulties experienced by students in the designing and execution of such a strategy? c) how will students, in interaction with the teacher and with their peers, gradually design and execute their investigation strategy in order to respond to the problem formulated? The project adopted an action research methodology. A careful record was kept of the events most relevant to the questions under study in each class. This data was used to prepare the class diaries - descriptive and reflective narratives prepared based on recorded audio and field notes made during participant observation in the context of the classroom. A content analysis of the diaries has identified a few elements that provide answers to the research questions raised. In order to plan and implement a research project with children in the 7/8 years old range require a high level of scaffolding to allow students to gradually build a coherent strategy to tackle the research problem. Teacher's role is crucial. The teacher, by questioning and inducing reasoning and discussion, promotes encourages and regulates the cognitive activity of students. Some level of autonomy should be given to the students in large group collaborative work.

  19. Industrial Ecology and Environmental Lean Management: Lights and Shadows

    Directory of Open Access Journals (Sweden)

    Giuseppe Ioppolo

    2014-09-01

    Full Text Available Current industrial production is driven by increasing globalization, which has led to a steady increase in production volumes and complexity of products aimed at the pursuit of meeting the needs of customers. In this context, one of the main tools in the management of customer value is Lean Manufacturing or Production, though it is considered primarily as a set of tools to reduce the total cost of the resources needed to achieve such needs. This philosophy has recently been enriched in the literature with case studies that link Lean Management (LM with the improvement of environmental sustainability. The consequence is an expansion of the Computer Integrated Manufacturing (CIM; indeed, CIM, currently, combining and integrating the key business functions (e.g., business, engineering, manufacturing, and information management with a view of the life cycle, does not highlight the strategic role of the environmental aspects. In order to deal with the increasingly rapid environmental degradation that is reflected in society, in terms of both economy and quality of life, Industrial Ecology (IE introduced a new paradigm of principles and instruments of analysis and decision support (e.g., Life Cycle Assessment—LCA, Social Life Cycle Assessment -SLCA, Material Flow Account—MFA, etc. that can be considered as the main basis for integrating the environmental aspects in each strategy, design, production, final product, and end of life management, through the re-engineering of processes and activities towards the development of an eco-industrial system. This paper presents the preliminary observations based on a analysis of both theories (LM-IE and provides a possible assessment of the key factors relevant to their integration in a “lean environmental management”, highlighting both positives (lights and possible barriers (shadows.

  20. Retracing Memories

    Science.gov (United States)

    Harrison, David L.

    2005-01-01

    There are plenty of paths to poetry but few are as accessible as retracing ones own memories. When students are asked to write about something they remember, they are given them the gift of choosing from events that are important enough to recall. They remember because what happened was funny or scary or embarrassing or heartbreaking or silly.…

  1. Memory consolidation

    NARCIS (Netherlands)

    Takashima, A.; Bakker, I.

    2016-01-01

    In order to make use of novel experiences and knowledge to guide our future behavior, we must keep large amounts of information accessible for retrieval. The memory system that stores this information needs to be flexible in order to rapidly incorporate incoming information, but also requires that

  2. Broadcast Memories

    Institute of Scientific and Technical Information of China (English)

    陈淑娴

    1995-01-01

    At the root of all memory is a communication among neurons,millions of neurons, passing signals to one another like the transistors in a computer. Transistors have to be linked by wires in order to communicate—but neurons,it now seems, are different. According to a recent study dnne at Stanford, neu-

  3. Concrete Memories

    DEFF Research Database (Denmark)

    Wiegand, Frauke Katharina

    2015-01-01

    This article traces the presence of Atlantikwall bunkers in amateur holiday snapshots and discusses the ambiguous role of the bunker site in visual cultural memory. Departing from my family’s private photo collection from twenty years of vacationing at the Danish West coast, the different mundane...

  4. Lost in Jupiter's Shadow: Can Resonant Charge Variations Explain Dust Grain Sizes in the Main Ring?

    Science.gov (United States)

    Jontof-Hutter, Daniel; Hamilton, D. P.

    2012-10-01

    Interplanetary impacts onto the tiny moons Metis and Adrastea replenish Jupiter's main ring with dusty ejecta of all sizes. The equilibrium size distribution present in the rings at a given time is a function of production and loss mechanisms, both of which may be vary with particle size. Loss mechanisms include collisions and dynamical processes. Here we explore some of the latter. Grains tend to pick up negative electric charges due to motion through Jupiter's plasma environment, and positive charges from the photoelectric effect of sunlight. The periodic interruption of sunlight in Jupiter's shadow causes the equilibrium electric charge, and hence the Lorentz force, to resonate with the Kepler orbital frequency. The eccentricity increases for grains moving radially inwards during the shadow transit, and decreases when grains move outward in the shadow, hence the azimuthal location of pericenter is important. For smaller grains, the eccentricity increases monotonically until they collide with Jupiter. For much larger grains, precession due to both the Lorentz force and planetary oblateness causes the eccentricity to oscillate periodically. We explore the shadow instability in the main ring for a variety of uniform plasma density models, comparing numerical data with a semi-analytic approximation. We find that the effect of the shadow dwindles in importance for plasma that is either too sparse or too dense. In sparse plasma, the charging timescale slows, limiting the change in electric potential from sunlight to shadow. In dense plasma, charging currents from the plasma overwhelm the photoelectric effect in sunlight, also resulting in a small change in electric potential. Between these two regimes, the shadow resonance efficiently removes grains up to a particular size threshold in the main ring. This size-dependent loss mechanism may contribute to the observed flattening in the size distribution index for smaller grains.

  5. A Method of Survey on Object-Oriented Shadow Detection & Removal for High Resolution Urban Aerial Colour Images

    OpenAIRE

    A.Amareswar Kumar,; B Mohan Reddy

    2015-01-01

    High-resolution remote sensing images offer great possibilities for urban mapping. Unfortunately, shadows cast by buildings during this some problems occurred .This paper mainly focus to get the high resolution colour remote sensing image, and also undertaken to remove the shaded region in the both urban and rural areas. The region growing thresholding algorithm is used to detect the shadow and extract the features from shadow region. Then determine whether those neighbouring pixe...

  6. Advanced dexterous manipulation for IED defeat : report on the feasibility of using the ShadowHand for remote operations.

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Robert J.

    2011-01-01

    Improvised Explosive Device (IED) defeat (IEDD) operations can involve intricate operations that exceed the current capabilities of the grippers on board current bombsquad robots. The Shadow Dexterous Hand from the Shadow Robot Company or 'ShadowHand' for short (www.shadowrobot.com) is the first commercially available robot hand that realistically replicates the motion, degrees-of-freedom and dimensions of a human hand (Figure 1). In this study we evaluate the potential for the ShadowHand to perform potential IED defeat tasks on a mobile platform.

  7. Analysis of shadowing effects on MIR photovoltaic and solar dynamic power systems

    Science.gov (United States)

    Fincannon, James

    1995-01-01

    The NASA Lewis Research Center is currently working with RSC-Energia, the Russian Space Agency, and Allied Signal in developing a flight demonstration solar dynamic power system. This type of power system is dependent upon solar flux that is reflected and concentrated into a thermal storage system to provide the thermal energy input to a closed-cycle Brayton heat engine. The solar dynamic unit will be flown on the Russian Mir space station in anticipation of use on the International Space Station Alpha. By the time the power system is launched, the Mir will be a spatially complex configuration which will have, in addition to the three-gimbaled solar dynamic unit, eleven solar array wings that are either fixed or track the Sun along one axis and a variety or repositionable habitation and experiment modules. The proximity of arrays to modules creates a situation which makes it highly probable that there will be varying solar flux due to shadowing on the solar dynamic unit and some of the arrays throughout the orbit. Shadowing causes fluctuations in the power output from the arrays and the solar dynamic power system, thus reducing the energy capabilities of the spacecraft. An assessment of the capabilities of the power system under these conditions is an important part in influencing the design and operations of the spacecraft and predicting its energy performance. This paper describes the results obtained from using the Orbiting Spacecraft Shadowing Analysis Station program that was integrated into the Station Power Analysis for Capability Evaluation (SPACE) electrical power system computer program. OSSA allows one to consider the numerous complex factors for analyzing the shadowing effects on the electrical power system including the variety of spacecraft hardware geometric configurations, yearly and daily orbital variations in the vehicle attitude and orbital maneuvers (for communications coverage, payload pointing requirements and rendezvous/docking with other

  8. Automated vessel shadow segmentation of fovea-centered spectral-domain images from multiple OCT devices

    Science.gov (United States)

    Wu, Jing; Gerendas, Bianca S.; Waldstein, Sebastian M.; Simader, Christian; Schmidt-Erfurth, Ursula

    2014-03-01

    Spectral-domain Optical Coherence Tomography (SD-OCT) is a non-invasive modality for acquiring high reso- lution, three-dimensional (3D) cross sectional volumetric images of the retina and the subretinal layers. SD-OCT also allows the detailed imaging of retinal pathology, aiding clinicians in the diagnosis of sight degrading diseases such as age-related macular degeneration (AMD) and glaucoma.1 Disease diagnosis, assessment, and treatment requires a patient to undergo multiple OCT scans, possibly using different scanning devices, to accurately and precisely gauge disease activity, progression and treatment success. However, the use of OCT imaging devices from different vendors, combined with patient movement may result in poor scan spatial correlation, potentially leading to incorrect patient diagnosis or treatment analysis. Image registration can be used to precisely compare disease states by registering differing 3D scans to one another. In order to align 3D scans from different time- points and vendors using registration, landmarks are required, the most obvious being the retinal vasculature. Presented here is a fully automated cross-vendor method to acquire retina vessel locations for OCT registration from fovea centred 3D SD-OCT scans based on vessel shadows. Noise filtered OCT scans are flattened based on vendor retinal layer segmentation, to extract the retinal pigment epithelium (RPE) layer of the retina. Voxel based layer profile analysis and k-means clustering is used to extract candidate vessel shadow regions from the RPE layer. In conjunction, the extracted RPE layers are combined to generate a projection image featuring all candidate vessel shadows. Image processing methods for vessel segmentation of the OCT constructed projection image are then applied to optimize the accuracy of OCT vessel shadow segmentation through the removal of false positive shadow regions such as those caused by exudates and cysts. Validation of segmented vessel shadows uses

  9. Shadows of CPR black holes and tests of the Kerr metric

    Energy Technology Data Exchange (ETDEWEB)

    Ghasemi-Nodehi, M.; Li, Zilong; Bambi, Cosimo [Fudan University, Department of Physics, Center for Field Theory and Particle Physics, Shanghai (China)

    2015-07-15

    Ww study the shadow of the Cardoso-Pani-Rico black hole for different values of the black hole spin a{sub *}, the deformation parameters ε{sub 3}{sup t} and ε{sub 3}{sup r}, and the viewing angle i. We find that the main impact of the deformation parameter ε{sub 3}{sup t} is the change of the size of the shadow, while the deformation parameter ε{sub 3}{sup r} affects the shape of its boundary. In general, it is impossible to test the Kerr metric, because the shadow of a Kerr black hole can be reproduced quite well by a black hole with non-vanishing ε{sub 3}{sup t} or ε{sub 3}{sup r}. Deviations from the Kerr geometry could be constrained in the presence of high quality data and in the favorable case of a black hole with high values of a{sub *} and i. However, the shadows of some black holes with non-vanishing ε{sub 3}{sup r} present peculiar features and the possible detection of these shadows could unambiguously distinguish these objects from the standard Kerr black holes of general relativity. (orig.)

  10. The Shadow Economy of Czech Republic and Tax Evasion: The Currency Demand Approach

    Directory of Open Access Journals (Sweden)

    Dennis Nchor

    2016-01-01

    Full Text Available This study investigates the shadow economy of Czech Republic and the associated losses in tax revenue. The presence of a shadow economy may not necessarily be bad for the economies in which they prevail but they could cause huge losses to government revenue and could also constitute serious violation of labour regulations. The study uses the Currency Demand Approach. It measures the size of the shadow economy in two stages: a the econometric estimation of an aggregate money demand equation b the calculation of the value of the shadow economy through the quantity theory of money. The key variables in the study include: the total currency held outside the banking system, the number of automatic teller machines, the deposit interest rate, GDP deflator, the average tax, velocity of money, nominal GDP and nominal money supply. The results from the study show that the shadow economy of Czech Republic on the average is about 20.9 % as at the end of 2013 and the country loses an average tax revenue of about 7.2 % of GDP yearly. The data was obtained from the World Bank country indicators and the International Financial Statistics.

  11. Observation of the Cosmic Ray Moon shadowing effect with the ARGO-YBJ experiment

    CERN Document Server

    Di Sciascio, G

    2011-01-01

    Cosmic rays are hampered by the Moon and a deficit in its direction is expected (the so-called \\emph{Moon shadow}). The Moon shadow is an important tool to determine the performance of an air shower array. In fact, the displacement of the shadow center, due to the bending effect of the Geomagnetic field on the propagation of cosmic rays, allows to set the energy scale of the primary particles inducing the showers observed by the detector. The shape of the shadow permits to determine the detector point spread function. The position of the deficit at high energy allows evaluating its pointing accuracy. Here we present the observation of the cosmic ray Moon shadowing effect carried out by the ARGO-YBJ experiment (Yangbajing Cosmic Ray Laboratory, Tibet, P.R. China, 4300 m a.s.l., 606 g/cm$^2$) in the multi-TeV energy region with high statistical significance (70 standard deviations). By means of an accurate Monte Carlo simulation of the cosmic rays propagation in the Earth-Moon system we have studied the role of...

  12. A method for image-based shadow interaction with virtual objects

    Directory of Open Access Journals (Sweden)

    Hyunwoo Ha

    2015-01-01

    Full Text Available A lot of researchers have been investigating interactive portable projection systems such as a mini-projector. In addition, in exhibition halls and museums, there is a trend toward using interactive projection systems to make viewing more exciting and impressive. They can also be applied in the field of art, for example, in creating shadow plays. The key idea of the interactive portable projection systems is to recognize the user׳s gesture in real-time. In this paper, a vision-based shadow gesture recognition method is proposed for interactive projection systems. The gesture recognition method is based on the screen image obtained by a single web camera. The method separates only the shadow area by combining the binary image with an input image using a learning algorithm that isolates the background from the input image. The region of interest is recognized with labeling the shadow of separated regions, and then hand shadows are isolated using the defect, convex hull, and moment of each region. To distinguish hand gestures, Hu׳s invariant moment method is used. An optical flow algorithm is used for tracking the fingertip. Using this method, a few interactive applications are developed, which are presented in this paper.

  13. Shadows of CPR black holes and tests of the Kerr metric

    CERN Document Server

    Ghasemi-Nodehi, Masoumeh; Bambi, Cosimo

    2015-01-01

    We study the shadow of the Cardoso-Pani-Rico (CPR) black hole for different values of the black hole spin $a_*$, the deformation parameters $\\epsilon_3^t$ and $\\epsilon_3^r$, and the viewing angle $i$. We find that the main impact of the deformation parameter $\\epsilon_3^t$ is the change of the size of the shadow, while the deformation parameter $\\epsilon_3^r$ affects the shape of its boundary. In general, it is impossible to test the Kerr metric, because the shadow of a Kerr black hole can be reproduced quite well by a black hole with non-vanishing $\\epsilon_3^t$ or $\\epsilon_3^r$. Deviations from the Kerr geometry could be constrained in the presence of high quality data and in the favorable case of a black hole with high values of $a_*$ and $i$. However, the shadows of some black holes with non-vanishing $\\epsilon_3^r$ present peculiar features and the possible detection of these shadows could unambiguously distinguish these objects from the standard Kerr black holes of general relativity.

  14. A DYNAMIC APPROACH TO CALCULATE SHADOW PRICES OF WATER RESOURCES FOR NINE MAJOR RIVERS IN CHINA

    Institute of Scientific and Technical Information of China (English)

    Jing HE; Xikang CHEN; Yong SHI

    2006-01-01

    China is experiencing from serious water issues. There are many differences among the Nine Major Rivers basins of China in the construction of dikes, reservoirs, floodgates, flood discharge projects, flood diversion projects, water ecological construction, water conservancy management, etc.The shadow prices of water resources for Nine Major Rivers can provide suggestions to the Chinese government. This article develops a dynamic shadow prices approach based on a multiperiod input-output optimizing model. Unlike previous approaches, the new model is based on the dynamic computable general equilibrium (DCGE) model to solve the problem of marginal long-term prices of water resources.First, definitions and algorithms of DCGE are elaborated. Second, the results of shadow prices of water resources for Nine Major Rivers in 1949-2050 in China using the National Water Conservancy input-holding-output table for Nine Major Rivers in 1999 are listed. A conclusion of this article is that the shadow prices of water resources for Nine Major Rivers are largely based on the extent of scarcity.Selling prices of water resources should be revised via the usage of parameters representing shadow prices.

  15. Shadow detection in camera-based vehicle detection: survey and analysis

    Science.gov (United States)

    Barcellos, Pablo; Gomes, Vitor; Scharcanski, Jacob

    2016-09-01

    The number of vehicles in circulation in modern urban centers has greatly increased, which motivates the development of automatic traffic monitoring systems. Consequently, camera-based traffic monitoring systems are becoming more widely used, since they offer important technological advantages in comparison with traditional traffic monitoring systems (e.g., simpler maintenance and more flexibility for the design of practical configurations). The segmentation of the foreground (i.e., vehicles) is a fundamental step in the workflow of a camera-based traffic monitoring system. However, foreground segmentation can be negatively affected by vehicle shadows. This paper discusses the types of shadow detection methods available in the literature, their advantages, disadvantages, and in which situations these methods can improve camera-based vehicle detection for traffic monitoring. In order to compare the performance of these different types of shadow detection methods, experiments are conducted with typical methods of each category using publicly available datasets. This work shows that shadow detection definitely can improve the reliability of traffic monitoring systems, but the choice of the type of shadow method depends on the system specifications (e.g., tolerated error), the availability of computational resources, and prior information about the scene and its illumination in regular operation conditions.

  16. Shadow analysis via the C+K Visioline: A technical note.

    Science.gov (United States)

    Houser, T; Zerweck, C; Grove, G; Wickett, R

    2017-11-01

    This research investigated the ability of shadow analysis (via the Courage + Khazaka Visioline and Image Pro Premiere 9.0 software) to accurately assess the differences in skin topography associated with photo aging. Analyses were performed on impressions collected from a microfinish comparator scale (GAR Electroforming) as well a series of impressions collected from the crow's feet region of 9 women who represent each point on the Zerweck Crow's Feet classification scale. Analyses were performed using a Courage + Khazaka Visioline VL 650 as well as Image Pro Premiere 9.0 software. Shadow analysis showed an ability to accurately measure the groove depth when measuring impressions collected from grooves of known depth. Several shadow analysis parameters showed a correlation with the expert grader ratings of crow's feet when averaging measurements taken from the North and South directions. The Max Depth parameter in particular showed a strong correlation with the expert grader's ratings which improved when a more sophisticated analysis was performed using Image Pro Premiere. When used properly, shadow analysis is effective at accurately measuring skin surface impressions for differences in skin topography. Shadow analysis is shown to accurately assess the differences across a range of crow's feet severity correlating to a 0-8 grader scale. The Visioline VL 650 is a good tool for this measurement, with room for improvement in analysis which can be achieved through third party image analysis software. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. Shadow detection and removal in RGB VHR images for land use unsupervised classification

    Science.gov (United States)

    Movia, A.; Beinat, A.; Crosilla, F.

    2016-09-01

    Nowadays, high resolution aerial images are widely available thanks to the diffusion of advanced technologies such as UAVs (Unmanned Aerial Vehicles) and new satellite missions. Although these developments offer new opportunities for accurate land use analysis and change detection, cloud and terrain shadows actually limit benefits and possibilities of modern sensors. Focusing on the problem of shadow detection and removal in VHR color images, the paper proposes new solutions and analyses how they can enhance common unsupervised classification procedures for identifying land use classes related to the CO2 absorption. To this aim, an improved fully automatic procedure has been developed for detecting image shadows using exclusively RGB color information, and avoiding user interaction. Results show a significant accuracy enhancement with respect to similar methods using RGB based indexes. Furthermore, novel solutions derived from Procrustes analysis have been applied to remove shadows and restore brightness in the images. In particular, two methods implementing the so called "anisotropic Procrustes" and the "not-centered oblique Procrustes" algorithms have been developed and compared with the linear correlation correction method based on the Cholesky decomposition. To assess how shadow removal can enhance unsupervised classifications, results obtained with classical methods such as k-means, maximum likelihood, and self-organizing maps, have been compared to each other and with a supervised clustering procedure.

  18. Pixel-wise orthogonal decomposition for color illumination invariant and shadow-free image.

    Science.gov (United States)

    Qu, Liangqiong; Tian, Jiandong; Han, Zhi; Tang, Yandong

    2015-02-09

    In this paper, we propose a novel, effective and fast method to obtain a color illumination invariant and shadow-free image from a single outdoor image. Different from state-of-the-art methods for shadow-free image that either need shadow detection or statistical learning, we set up a linear equation set for each pixel value vector based on physically-based shadow invariants, deduce a pixel-wise orthogonal decomposition for its solutions, and then get an illumination invariant vector for each pixel value vector on an image. The illumination invariant vector is the unique particular solution of the linear equation set, which is orthogonal to its free solutions. With this illumination invariant vector and Lab color space, we propose an algorithm to generate a shadow-free image which well preserves the texture and color information of the original image. A series of experiments on a diverse set of outdoor images and the comparisons with the state-of-the-art methods validate our method.

  19. Noise-free accurate count of microbial colonies by time-lapse shadow image analysis.

    Science.gov (United States)

    Ogawa, Hiroyuki; Nasu, Senshi; Takeshige, Motomu; Funabashi, Hisakage; Saito, Mikako; Matsuoka, Hideaki

    2012-12-01

    Microbial colonies in food matrices could be counted accurately by a novel noise-free method based on time-lapse shadow image analysis. An agar plate containing many clusters of microbial colonies and/or meat fragments was trans-illuminated to project their 2-dimensional (2D) shadow images on a color CCD camera. The 2D shadow images of every cluster distributed within a 3-mm thick agar layer were captured in focus simultaneously by means of a multiple focusing system, and were then converted to 3-dimensional (3D) shadow images. By time-lapse analysis of the 3D shadow images, it was determined whether each cluster comprised single or multiple colonies or a meat fragment. The analytical precision was high enough to be able to distinguish a microbial colony from a meat fragment, to recognize an oval image as two colonies contacting each other, and to detect microbial colonies hidden under a food fragment. The detection of hidden colonies is its outstanding performance in comparison with other systems. The present system attained accuracy for counting fewer than 5 colonies and is therefore of practical importance.

  20. Measuring energy efficiency in economics: Shadow value approach

    Science.gov (United States)

    Khademvatani, Asgar

    For decades, academic scholars and policy makers have commonly applied a simple average measure, energy intensity, for studying energy efficiency. In contrast, we introduce a distinctive marginal measure called energy shadow value (SV) for modeling energy efficiency drawn on economic theory. This thesis demonstrates energy SV advantages, conceptually and empirically, over the average measure recognizing marginal technical energy efficiency and unveiling allocative energy efficiency (energy SV to energy price). Using a dual profit function, the study illustrates how treating energy as quasi-fixed factor called quasi-fixed approach offers modeling advantages and is appropriate in developing an explicit model for energy efficiency. We address fallacies and misleading results using average measure and demonstrate energy SV advantage in inter- and intra-country energy efficiency comparison. Energy efficiency dynamics and determination of efficient allocation of energy use are shown through factors impacting energy SV: capital, technology, and environmental obligations. To validate the energy SV, we applied a dual restricted cost model using KLEM dataset for the 35 US sectors stretching from 1958 to 2000 and selected a sample of the four sectors. Following the empirical results, predicted wedges between energy price and the SV growth indicate a misallocation of energy use in stone, clay and glass (SCG) and communications (Com) sectors with more evidence in the SCG compared to the Com sector, showing overshoot in energy use relative to optimal paths and cost increases from sub-optimal energy use. The results show that energy productivity is a measure of technical efficiency and is void of information on the economic efficiency of energy use. Decomposing energy SV reveals that energy, capital and technology played key roles in energy SV increases helping to consider and analyze policy implications of energy efficiency improvement. Applying the marginal measure, we also

  1. The betrayal of democracy: Tiananmen's shadow over Japan

    Directory of Open Access Journals (Sweden)

    Jing Zhao

    2008-12-01

    Full Text Available La heroica lucha del pueblo chino por la libertad política en 1989 estimuló a la Europa del Este y a la URSS a abandonar su sistema de partido único. La Guerra Fría terminó abruptamente bajo el acicate del incidente de la Plaza Tiananmen. Este artículo explora el otro lado oscuro del incidente de Tiananmen en el escenario internacional: su profunda sombra sobre Japón. En base a la experiencia personal del autor, el artículo revisa y analiza el fracaso de Japón en su transformación política en la región durante este período histórico desde dos aspectos: 1 ¿Por qué y cómo el gobierno japonés tuvo que seguir a China económicamente? 2 ¿Por qué y cómo el gobierno japonés traicionó la democracia y los derechos humanos? El artículo concluye que las relaciones Chino-japonesas deberían basarse en los  principios de derechos humanos y democracia._________________ABSTRACT:The Chinese people's heroic struggle for political freedom in 1989 encouraged East Europe and the USSR to abandon their single-party system. The Cold War ended abruptly under the stimulus of the Tiananmen Square Incident. This article explores the other dark side of the Tiananmen Incident in the international stage: its deep shadow over Japan. Based on the author's personal experience, the article records, reviews and analyzes Japan's failure in its political transformation in the region during this historical period from two aspects: 1 Why and how the Japanese government had to engage China economically?; 2 Why and how the Japanese government betrayed democracy and human rights regarding China? The article concludes that Sino-Japanese relations should be based on principles of human rights and democracy.

  2. Holographic Memories

    DEFF Research Database (Denmark)

    Ramanujam, P.S.; Holme, NCR; Berg, RH

    1999-01-01

    A Two-dimensional holographic memory for archival storage is described. Assuming a coherent transfer function, an A4 page can be stored at high resolution in an area of 1 mm(2). Recently developed side-chain liquid crystalline azobenzene polyesters are found to be suitable media for holographic...... storage. They exhibit high resolution, high diffraction efficiency, have long storage life, are fully erasable and are mechanically stable....

  3. Transactional Memory

    OpenAIRE

    Grahn, Håkan

    2010-01-01

    Current and future processor generations are based on multicore architectures where the performance increase comes from an increasing number of cores on a chip. In order to utilize the performance potential of multicore architectures the programs also need to be parallel, but writing parallel programs is a non-trivial task. Transactional memory tries to ease parallel program development by providing atomic and isolated execution of code sequences, enabling software composability and protected...

  4. SHADOWS CAST BY A WARP IN THE HD 142527 PROTOPLANETARY DISK

    Energy Technology Data Exchange (ETDEWEB)

    Marino, S.; Perez, S.; Casassus, S., E-mail: smarino@das.uchile.cl [Departamento de Astronomía, Universidad de Chile, Casilla 36-D Santiago (Chile)

    2015-01-10

    Detailed observations of gaps in protoplanetary disks have revealed structures that drive current research on circumstellar disks. One such feature is the two intensity nulls seen along the outer disk of the HD 142527 system, which are particularly well traced in polarized differential imaging. Here we propose that these are shadows cast by the inner disk. The inner and outer disk are thick, in terms of the unit-opacity surface in the H band, so that the shape and orientation of the shadows inform on the three-dimensional structure of the system. Radiative transfer predictions on a parametric disk model allow us to conclude that the relative inclination between the inner and outer disks is 70° ± 5°. This finding taps the potential of high-contrast imaging of circumstellar disks, and bears consequences on the gas dynamics of gapped disks, as well as on the physical conditions in the shadowed regions.

  5. Properties and Microstructure of One-Step Cold Rolled Steel Strip for Shadow Mask

    Institute of Scientific and Technical Information of China (English)

    LIANG Xuan; LI Jun; PENG Ying-hong

    2008-01-01

    The effect of recrystallization annealing temperature on the properties and microstructure of one-step cold rolled steel strip for shadow mask was studied.The results showed that there was no yield point elongation when the tensile tests were performed on the samples for annealing temperatures ranging from 750℃ to 810 ℃.Moreover,increasing annealing temperature resulted in large grains,which was beneficial to the formability and magnetic property of steel strips.On the other hand,when the sample was annealed at 840 ℃,its microstructure showed ununifortuity with 0.04% yield point elongation,which was not good for the function of the shadow mask.Therefore,the proper recrystallization annealing temperature was about 810 ℃ for the present steel strip for shadow mask.

  6. Heliostat blocking and shadowing efficiency in the video-game era

    Energy Technology Data Exchange (ETDEWEB)

    Ramos, Alberto [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Ramos, Francisco [Nevada Software Informatica S.L., Madrid (Spain)

    2014-02-15

    Blocking and shadowing is one of the key effects in designing and evaluating a thermal central receiver solar tower plant. Therefore it is convenient to develop efficient algorithms to compute the area of an heliostat blocked or shadowed by the rest of the field. In this paper we explore the possibility of using very efficient clipping algorithms developed for the video game and imaging industry to compute the blocking and shadowing efficiency of a solar thermal plant layout. We propose an algorithm valid for arbitrary position, orientation and size of the heliostats. This algorithm turns out to be very accurate, free of assumptions and fast. We show the feasibility of the use of this algorithm to the optimization of a solar plant by studying a couple of examples in detail.

  7. Moon shadow observation with ANTARES and KM3NeT neutrino telescope

    Directory of Open Access Journals (Sweden)

    Sanguineti Matteo

    2016-01-01

    Full Text Available The ANTARES detector is the largest neutrino telescope currently in operation in the Northern Hemisphere. The search for point-like neutrino sources is one of the main goals of ANTARES, so a reliable way to evaluate the detector pointing performance is needed. The Moon shadow measurement, i.e. the deficit in the atmospheric muon flux in the direction of the Moon induced by absorption of cosmic rays, allows the estimation of the angular resolution and the pointing accuracy. The 2007–2012 ANTARES data set shows a significance of Moon shadowing around 3σ. This is the first measurement of the ANTARES angular resolution and absolute pointing for atmospheric muons using a celestial calibration source. The same approach has been used to estimate also the expected Moon shadow significance with the KM3NeT-ARCA detector, the future cubic kilometre scale detector that will be installed in Sicily.

  8. Genotyping of simple sequence repeats--factors implicated in shadow band generation revisited.

    Science.gov (United States)

    Olejniczak, Marta; Krzyzosiak, Wlodzimierz J

    2006-10-01

    PCR amplification of microsatellite sequences generates, besides the main product corresponding to allele size, also additional, undesired products usually shorter by multiples of the repeated unit. These extra products known as shadow bands or stutter products may complicate genotyping. The mechanism by which these artifacts are formed is not well understood and so no effective remedy has been found to cope with these spurious products. In this study, using the DNA templates containing the CAG/CTG repeats flanked by gene-specific sequences and universal priming sites, we analyzed the effects of many PCR variables on the shadow band generation. The most important result was that at the decreased temperature of the denaturation step during PCR cycling the shadow bands were either not formed or were strongly suppressed. Several possible sources of this effect are discussed.

  9. Shape and position of the shadow in the {delta} = 2 Tomimatsu-Sato spacetime

    Energy Technology Data Exchange (ETDEWEB)

    Bambi, Cosimo; Yoshida, Naoki, E-mail: cosimo.bambi@ipmu.j, E-mail: naoki.yoshida@ipmu.j [Institute for the Physics and Mathematics of the Universe, University of Tokyo, Kashiwa, Chiba 277-8583 (Japan)

    2010-10-21

    Within 5-10 years, very long baseline interferometry facilities will be able to observe the 'shadow' of super-massive black hole candidates. This will allow us, for the first time, to test gravity in the strong field regime. In this paper, we numerically study the photon orbits in the {delta} = 2 Tomimatsu-Sato spacetime. The {delta} = 2 Tomimatsu-Sato spacetime is a stationary, axisymmetric and asymptotically flat exact solution of the vacuum Einstein equations. We compare the associated shadow with the one of Kerr black holes. The shape of the shadow in the {delta} = 2 Tomimatsu-Sato spacetime is oblate and the difference between the two axes can be as high as 6% when viewed on the equatorial plane. We argue that future space sub-mm interferometers (e.g. VSOP-3) may distinguish the two cases, and thus are able to test the cosmic censorship conjecture.

  10. Les risques du shadow banking en Europe : le point de vue du superviseur bancaire

    OpenAIRE

    2013-01-01

    Face aux défis soulevés par le Shadow banking en termes de stabilité financière, l?article aborde deux questions de fond. D?une part, il présente les risques posés par le Shadow banking et montre que le Shadow banking est porteur de risques intrinsèques et d?interactions complexes avec le secteur bancaire. D?autre part, il s?attache à déterminer les modalités les mieux adaptées de la réglementation pour y faire face. L?article décrit les renforcements majeurs de la réglementation bancaire qui...

  11. Elegant Shadow Making Tiny Force Visible for Water-Walking Arthropods and Updated Archimedes' Principle.

    Science.gov (United States)

    Zheng, Yelong; Lu, Hongyu; Yin, Wei; Tao, Dashuai; Shi, Lichun; Tian, Yu

    2016-10-07

    Forces acted on legs of water-walking arthropods with weights in dynes are of great interest for entomologist, physicists, and engineers. While their floating mechanism has been recognized, the in vivo leg forces stationary have not yet been simultaneously achieved. In this study, their elegant bright-edged leg shadows are used to make the tiny forces visible and measurable based on the updated Archimedes' principle. The force was approximately proportional to the shadow area with a resolution from nanonewton to piconewton/pixel. The sum of leg forces agreed well with the body weight measured with an accurate electronic balance, which verified updated Archimedes' principle at the arthropod level. The slight changes of vertical body weight focus position and the body pitch angle have also been revealed for the first time. The visualization of tiny force by shadow is cost-effective and very sensitive and could be used in many other applications.

  12. A Context-Aware Method for Authentically Simulating Outdoors Shadows for Mobile Augmented Reality.

    Science.gov (United States)

    Barreira, Joao; Bessa, Maximino; Barbosa, Luis; Magalhaes, Luis

    2017-03-01

    Visual coherence between virtual and real objects is a major issue in creating convincing augmented reality (AR) applications. To achieve this seamless integration, actual light conditions must be determined in real time to ensure that virtual objects are correctly illuminated and cast consistent shadows. In this paper, we propose a novel method to estimate daylight illumination and use this information in outdoor AR applications to render virtual objects with coherent shadows. The illumination parameters are acquired in real time from context-aware live sensor data. The method works under unprepared natural conditions. We also present a novel and rapid implementation of a state-of-the-art skylight model, from which the illumination parameters are derived. The Sun's position is calculated based on the user location and time of day, with the relative rotational differences estimated from a gyroscope, compass and accelerometer. The results illustrated that our method can generate visually credible AR scenes with consistent shadows rendered from recovered illumination.

  13. A new method for shadow calculations: application to parameterised axisymmetric black holes

    CERN Document Server

    Younsi, Ziri; Rezzolla, Luciano; Konoplya, Roman; Mizuno, Yosuke

    2016-01-01

    International efforts from the Black Hole Camera and Event Horizon Telescope projects, using mm and sub-mm very long baseline interferometry, are soon expected to provide the first images of the shadow cast by the candidate supermassive black hole in our Galactic center, Sagittarius A*. Observations of this shadow would provide direct evidence of the existence of astrophysical black holes. Although it is expected that astrophysical black holes are described by the axisymmetric Kerr solution, there also exist many other black hole solutions, both in general relativity and in other theories of gravity, which cannot presently be ruled out. To this end, we present calculations of black hole shadow images from various metric theories of gravity as described by our recent work on a general parameterisation of axisymmetric black holes [R. Konoplya, L. Rezzolla and A. Zhidenko, Phys. Rev. D 93, 064015 (2016)]. An algorithm to perform general ray-tracing calculations for any metric theory of gravity is first outlined ...

  14. Observation of the cosmic-ray shadow of the Moon with IceCube

    CERN Document Server

    Aartsen, M G; Abdou, Y; Ackermann, M; Adams, J; Aguilar, J A; Ahlers, M; Altmann, D; Auffenberg, J; Bai, X; Baker, M; Barwick, S W; Baum, V; Bay, R; Beatty, J J; Bechet, S; Tjus, J Becker; Becker, K -H; Bell, M; Benabderrahmane, M L; BenZvi, S; Berdermann, J; Berghaus, P; Berley, D; Bernardini, E; Bernhard, A; Bertrand, D; Besson, D Z; Binder, G; Bindig, D; Bissok, M; Blaufuss, E; Blumenthal, J; Boersma, D J; Bohaichuk, S; Bohm, C; Bose, D; Böser, S; Botner, O; Brayeur, L; Bretz, H -P; Brown, A M; Bruijn, R; Brunner, J; Carson, M; Casey, J; Casier, M; Chirkin, D; Christov, A; Christy, B; Clark, K; Clevermann, F; Coenders, S; Cohen, S; Cowen, D F; Silva, A H Cruz; Danninger, M; Daughhetee, J; Davis, J C; De Clercq, C; De Ridder, S; Desiati, P; de With, M; DeYoung, T; Díaz-Vélez, J C; Dunkman, M; Eagan, R; Eberhardt, B; Eisch, J; Ellsworth, R W; Euler, S; Evenson, P A; Fadiran, O; Fazely, A R; Fedynitch, A; Feintzeig, J; Feusels, T; Filimonov, K; Finley, C; Fischer-Wasels, T; Flis, S; Franckowiak, A; Franke, R; Frantzen, K; Fuchs, T; Gaisser, T K; Gallagher, J; Gerhardt, L; Gladstone, L; Glüsenkamp, T; Goldschmidt, A; Golup, G; Gonzalez, J G; Goodman, J A; Góra, D; Grandmont, D T; Grant, D; Groß, A; Ha, C; Ismail, A Haj; Hallen, P; Hallgren, A; Halzen, F; Hanson, K; Heereman, D; Heinen, D; Helbing, K; Hellauer, R; Hickford, S; Hill, G C; Hoffman, K D; Hoffmann, R; Homeier, A; Hoshina, K; Huelsnitz, W; Hulth, P O; Hultqvist, K; Hussain, S; Ishihara, A; Jacobi, E; Jacobsen, J; Jagielski, K; Japaridze, G S; Jero, K; Jlelati, O; Kaminsky, B; Kappes, A; Karg, T; Karle, A; Kelley, J L; Kiryluk, J; Kislat, F; Kläs, J; Klein, S R; Köhne, J -H; Kohnen, G; Kolanoski, H; Köpke, L; Kopper, C; Kopper, S; Koskinen, D J; Kowalski, M; Krasberg, M; Krings, K; Kroll, G; Kunnen, J; Kurahashi, N; Kuwabara, T; Labare, M; Landsman, H; Larson, M J; Lesiak-Bzdak, M; Leuermann, M; Leute, J; Lünemann, J; Madsen, J; Maruyama, R; Mase, K; Matis, H S; McNally, F; Meagher, K; Merck, M; Mészáros, P; Meures, T; Miarecki, S; Middell, E; Milke, N; Miller, J; Mohrmann, L; Montaruli, T; Morse, R; Nahnhauer, R; Naumann, U; Niederhausen, H; Nowicki, S C; Nygren, D R; Obertacke, A; Odrowski, S; Olivas, A; Olivo, M; O'Murchadha, A; Paul, L; Pepper, J A; Heros, C Pérez de los; Pfendner, C; Pieloth, D; Pinat, E; Pirk, N; Posselt, J; Price, P B; Przybylski, G T; Rädel, L; Rameez, M; Rawlins, K; Redl, P; Reimann, R; Resconi, E; Rhode, W; Ribordy, M; Richman, M; Riedel, B; Rodrigues, J P; Rott, C; Ruhe, T; Ruzybayev, B; Ryckbosch, D; Saba, S M; Salameh, T; Sander, H -G; Santander, M; Sarkar, S; Schatto, K; Scheel, M; Scheriau, F; Schmidt, T; Schmitz, M; Schoenen, S; Schöneberg, S; Schönwald, A; Schukraft, A; Schulte, L; Schulz, O; Seckel, D; Sestayo, Y; Seunarine, S; Sheremata, C; Smith, M W E; Soldin, D; Spiczak, G M; Spiering, C; Stamatikos, M; Stanev, T; Stasik, A; Stezelberger, T; Stokstad, R G; Stößl, A; Strahler, E A; Ström, R; Sullivan, G W; Taavola, H; Taboada, I; Tamburro, A; Tepe, A; Ter-Antonyan, S; Tešić, G; Tilav, S; Toale, P A; Toscano, S; Usner, M; van der Drift, D; van Eijndhoven, N; Van Overloop, A; van Santen, J; Vehring, M; Voge, M; Vraeghe, M; Walck, C; Waldenmaier, T; Wallraff, M; Wasserman, R; Weaver, Ch; Wellons, M; Wendt, C; Westerhoff, S; Whitehorn, N; Wiebe, K; Wiebusch, C H; Williams, D R; Wissing, H; Wolf, M; Wood, T R; Woschnagg, K; Xu, C; Xu, D L; Xu, X W; Yanez, J P; Yodh, G; Yoshida, S; Zarzhitsky, P; Ziemann, J; Zierke, S; Zoll, M

    2013-01-01

    We report on the observation of a significant deficit of cosmic rays from the direction of the Moon with the IceCube detector. The study of this "Moon shadow" is used to characterize the angular resolution and absolute pointing capabilities of the detector. The detection is based on data taken in two periods before the completion of the detector: between April 2008 and May 2009, when IceCube operated in a partial configuration with 40 detector strings deployed in the South Pole ice, and between May 2009 and May 2010 when the detector operated with 59 strings. Using two independent analysis methods, the Moon shadow has been observed to high significance (> 6 sigma) in both detector configurations. The observed location of the shadow center is within 0.2 degrees of its expected position when geomagnetic deflection effects are taken into account. This measurement validates the directional reconstruction capabilities of IceCube.

  15. Shadowing on Apollo 12 Solar Cells and Possible Movement of the ALSEP Central Station

    Science.gov (United States)

    Berman, Paul A.; Williams, David R.

    2014-01-01

    A fortuitous arrangement of a west-facing solar cell and a bracket on the Apollo 12 ALSEP (Apollo Lunar Surface Experiments Package) has allowed us to precisely determine the relative position of the Sun near sunset relative to the Apollo 12 central station over a period of nearly 8 years. The small bracket, mounted on the central station due west of the cell, casts a shadow on the cell near sunset, decreasing the output of the cell proportional to the area of shadow covering the cell. The pattern of shadowing by the bracket gives good agreement with the known change of solar azimuth on a yearly timescale, but the pattern gradually but constantly changed from year-to-year, in a manner inconsistent with the known and changing position of the Sun.

  16. Shape and position of the shadow in the $\\delta = 2$ Tomimatsu-Sato space-time

    CERN Document Server

    Bambi, Cosimo

    2010-01-01

    Within 5-10 years, very long baseline interferometry facilities will be able to observe the "shadow" of super-massive black hole candidates. This will allow, for the first time, to test gravity in the strong field regime. In this paper, we study numerically the photon orbits in the $\\delta = 2$ Tomimatsu-Sato space-time. The $\\delta = 2$ Tomimatsu-Sato space-time is a stationary, axisymmetric, and asymptotically flat exact solution of the vacuum Einstein equations. We compare the associated shadow with the one of Kerr black holes. The shape of the shadow in the $\\delta = 2$ Tomimatsu-Sato space-time is oblate and the difference between the two axes can be as high as 6% when viewed on the equatorial plane. We argue that future space sub-mm interferometers (e.g. VSOP-3) may distinguish the two cases, and thus are able to test the Cosmic Censorship Conjecture.

  17. Shape and position of the shadow in the δ = 2 Tomimatsu-Sato spacetime

    Science.gov (United States)

    Bambi, Cosimo; Yoshida, Naoki

    2010-10-01

    Within 5-10 years, very long baseline interferometry facilities will be able to observe the 'shadow' of super-massive black hole candidates. This will allow us, for the first time, to test gravity in the strong field regime. In this paper, we numerically study the photon orbits in the δ = 2 Tomimatsu-Sato spacetime. The δ = 2 Tomimatsu-Sato spacetime is a stationary, axisymmetric and asymptotically flat exact solution of the vacuum Einstein equations. We compare the associated shadow with the one of Kerr black holes. The shape of the shadow in the δ = 2 Tomimatsu-Sato spacetime is oblate and the difference between the two axes can be as high as 6% when viewed on the equatorial plane. We argue that future space sub-mm interferometers (e.g. VSOP-3) may distinguish the two cases, and thus are able to test the cosmic censorship conjecture.

  18. Amplification of dust loading in Martian dust devils by self-shadowing

    CERN Document Server

    Kuepper, Markus

    2016-01-01

    Insolation of the Martian soil leads to a sub-surface overpressure due to thermal creep gas flow. This could support particle entrainment into the atmosphere. Short time shadowing e.g. by the traverse of a larger dust devil would enhance this effect. We find in microgravity experiments that mass ejection rates are increased by a factor of 10 for several seconds if a light source of 12.6 kW/$\\rm m^2$ is turned off. Scaled to Mars this implies that self-shadowing of a partially opaque dust devil might lead to a strongly amplified flux of lifted material. We therefore suggest that self-shadowing might be a mechanism on Mars to increase the total dust loading of a dust devil and keep it self-sustained.

  19. Optical depth measurements by shadow-band radiometers and their uncertainties.

    Science.gov (United States)

    Alexandrov, Mikhail D; Kiedron, Peter; Michalsky, Joseph J; Hodges, Gary; Flynn, Connor J; Lacis, Andrew A

    2007-11-20

    Shadow-band radiometers in general, and especially the Multi-Filter Rotating Shadow-band Radiometer (MFRSR), are widely used for atmospheric optical depth measurements. The major programs running MFRSR networks in the United States include the Department of Energy Atmospheric Radiation Measurement (ARM) Program, U.S. Department of Agriculture UV-B Monitoring and Research Program, National Oceanic and Atmospheric Administration Surface Radiation (SURFRAD) Network, and NASA Solar Irradiance Research Network (SIRN). We discuss a number of technical issues specific to shadow-band radiometers and their impact on the optical depth measurements. These problems include instrument tilt and misalignment, as well as some data processing artifacts. Techniques for data evaluation and automatic detection of some of these problems are described.

  20. [Neural correlates of memory].

    Science.gov (United States)

    Fujii, Toshikatsu

    2013-01-01

    Memory can be divided into several types, although all of them involve three successive processes: encoding, storage, and retrieval. In terms of the duration of retention, neurologists classify memory into immediate, recent, and remote memories, whereas psychologists classify memory into short-term and long-term memories. In terms of the content, episodic, semantic, and procedural memories are considered to be different types of memory. Furthermore, researchers on memory have proposed relatively new concepts of memory, i.e., working memory and prospective memory. This article first provides explanations for these several types of memory. Next, neuropsychological characteristics of amnesic syndrome are briefly outlined. Finally, how several different types of memory are affected (or preserved) in patients with amnesic syndrome is described.

  1. Power fluctuation and power loss of wind turbines due to wind shear and tower shadow

    Science.gov (United States)

    Wen, Binrong; Wei, Sha; Wei, Kexiang; Yang, Wenxian; Peng, Zhike; Chu, Fulei

    2017-09-01

    The magnitude and stability of power output are two key indices of wind turbines. This study investigates the effects of wind shear and tower shadow on power output in terms of power fluctuation and power loss to estimate the capacity and quality of the power generated by a wind turbine. First, wind speed models, particularly the wind shear model and the tower shadow model, are described in detail. The widely accepted tower shadow model is modified in view of the cone-shaped towers of modern large-scale wind turbines. Power fluctuation and power loss due to wind shear and tower shadow are analyzed by performing theoretical calculations and case analysis within the framework of a modified version of blade element momentum theory. Results indicate that power fluctuation is mainly caused by tower shadow, whereas power loss is primarily induced by wind shear. Under steady wind conditions, power loss can be divided into wind farm loss and rotor loss. Wind farm loss is constant at 3 α(3 α-1) R 2/(8 H 2). By contrast, rotor loss is strongly influenced by the wind turbine control strategies and wind speed. That is, when the wind speed is measured in a region where a variable-speed controller works, the rotor loss stabilizes around zero, but when the wind speed is measured in a region where the blade pitch controller works, the rotor loss increases as the wind speed intensifies. The results of this study can serve as a reference for accurate power estimation and strategy development to mitigate the fluctuations in aerodynamic loads and power output due to wind shear and tower shadow.

  2. Power fluctuation and power loss of wind turbines due to wind shear and tower shadow

    Science.gov (United States)

    Wen, Binrong; Wei, Sha; Wei, Kexiang; Yang, Wenxian; Peng, Zhike; Chu, Fulei

    2017-05-01

    The magnitude and stability of power output are two key indices of wind turbines. This study investigates the effects of wind shear and tower shadow on power output in terms of power fluctuation and power loss to estimate the capacity and quality of the power generated by a wind turbine. First, wind speed models, particularly the wind shear model and the tower shadow model, are described in detail. The widely accepted tower shadow model is modified in view of the cone-shaped towers of modern large-scale wind turbines. Power fluctuation and power loss due to wind shear and tower shadow are analyzed by performing theoretical calculations and case analysis within the framework of a modified version of blade element momentum theory. Results indicate that power fluctuation is mainly caused by tower shadow, whereas power loss is primarily induced by wind shear. Under steady wind conditions, power loss can be divided into wind farm loss and rotor loss. Wind farm loss is constant at 3α(3α-1)R 2/(8H 2). By contrast, rotor loss is strongly influenced by the wind turbine control strategies and wind speed. That is, when the wind speed is measured in a region where a variable-speed controller works, the rotor loss stabilizes around zero, but when the wind speed is measured in a region where the blade pitch controller works, the rotor loss increases as the wind speed intensifies. The results of this study can serve as a reference for accurate power estimation and strategy development to mitigate the fluctuations in aerodynamic loads and power output due to wind shear and tower shadow.

  3. Incorporating animal behavior into seed dispersal models: implications for seed shadows.

    Science.gov (United States)

    Russo, Sabrina E; Portnoy, Stephen; Augspurger, Carol K

    2006-12-01

    Seed dispersal fundamentally influences plant population and community dynamics but is difficult to quantify directly. Consequently, models are frequently used to describe the seed shadow (the seed deposition pattern of a plant population). For vertebrate-dispersed plants, animal behavior is known to influence seed shadows but is poorly integrated in seed dispersal models. Here, we illustrate a modeling approach that incorporates animal behavior and develop a stochastic, spatially explicit simulation model that predicts the seed shadow for a primate-dispersed tree species (Virola calophylla, Myristicaceae) at the forest stand scale. The model was parameterized from field-collected data on fruit production and seed dispersal, behaviors and movement patterns of the key disperser, the spider monkey (Ateles paniscus), densities of dispersed and non-dispersed seeds, and direct estimates of seed dispersal distances. Our model demonstrated that the spatial scale of dispersal for this V. calophylla population was large, as spider monkeys routinely dispersed seeds >100 m, a commonly used threshold for long-distance dispersal. The simulated seed shadow was heterogeneous, with high spatial variance in seed density resulting largely from behaviors and movement patterns of spider monkeys that aggregated seeds (dispersal at their sleeping sites) and that scattered seeds (dispersal during diurnal foraging and resting). The single-distribution dispersal kernels frequently used to model dispersal substantially underestimated this variance and poorly fit the simulated seed-dispersal curve, primarily because of its multimodality, and a mixture distribution always fit the simulated dispersal curve better. Both seed shadow heterogeneity and dispersal curve multimodality arose directly from these different dispersal processes generated by spider monkeys. Compared to models that did not account for disperser behavior, our modeling approach improved prediction of the seed shadow of this V

  4. Automatic Detection of Clouds and Shadows Using High Resolution Satellite Image Time Series

    Science.gov (United States)

    Champion, Nicolas

    2016-06-01

    Detecting clouds and their shadows is one of the primaries steps to perform when processing satellite images because they may alter the quality of some products such as large-area orthomosaics. The main goal of this paper is to present the automatic method developed at IGN-France for detecting clouds and shadows in a sequence of satellite images. In our work, surface reflectance orthoimages are used. They were processed from initial satellite images using a dedicated software. The cloud detection step consists of a region-growing algorithm. Seeds are firstly extracted. For that purpose and for each input ortho-image to process, we select the other ortho-images of the sequence that intersect it. The pixels of the input ortho-image are secondly labelled seeds if the difference of reflectance (in the blue channel) with overlapping ortho-images is bigger than a given threshold. Clouds are eventually delineated using a region-growing method based on a radiometric and homogeneity criterion. Regarding the shadow detection, our method is based on the idea that a shadow pixel is darker when comparing to the other images of the time series. The detection is basically composed of three steps. Firstly, we compute a synthetic ortho-image covering the whole study area. Its pixels have a value corresponding to the median value of all input reflectance ortho-images intersecting at that pixel location. Secondly, for each input ortho-image, a pixel is labelled shadows if the difference of reflectance (in the NIR channel) with the synthetic ortho-image is below a given threshold. Eventually, an optional region-growing step may be used to refine the results. Note that pixels labelled clouds during the cloud detection are not used for computing the median value in the first step; additionally, the NIR input data channel is used to perform the shadow detection, because it appeared to better discriminate shadow pixels. The method was tested on times series of Landsat 8 and Pl

  5. Numerical analysis of the galvanic coupling in the shadow corrosion of zirconium alloy

    Science.gov (United States)

    Buttin, P.; Malki, B.; Barberis, P.; Baroux, B.

    2012-01-01

    Shadow corrosion of Zircaloy cladding in a boiling water reactor is numerically studied using finite elements modelling. The Laplace equation is solved using boundary conditions determined by an empirical law of the anodic oxidation of Zircaloy. The effects of the distance between electrodes, the electrolyte conductivity and the parameters relating to oxido-reduction reaction are specifically investigated. It is shown that if the conductivity and reaction rates at the electrodes are high enough, the level of shadow corrosion increases drastically. A particular attention is given to the interfacial resistance induced by the potential drop in the oxide film.

  6. Thermal Warpage Measurement of Electronic Packages by Shadow Moiré with Phase Stepping Technique

    Institute of Scientific and Technical Information of China (English)

    Yinyan Wang

    2011-01-01

    Phase-stepping technique is applied to the analysis of fringe patterns of shadow moiré of electronic packages.Sensitivity of the fringe pattern analysis is demonstrated to be significantly increased. Thermally induced warpage of electronic packages is successfully measured in real-time as the sample is driven through a simulated reflow process.The paper discusses the technique of phase stepping,noise filtering and its application to the shadow moiré method.Applications of the technology are presented.

  7. Nuclear shadowing and extraction of Fp2-Fn2 at small x from deuteron collider data.

    Science.gov (United States)

    Frankfurt, L; Guzey, V; Strikman, M

    2003-11-14

    We demonstrate that leading twist nuclear shadowing leads to large corrections for the extraction of the neutron structure function Fn2 from the future deuteron collider data both in the inclusive and in the tagged structure function modes. We suggest several strategies to address the extraction of Fn2 and to measure at the same time the effect of nuclear shadowing via the measurement of the distortion of the proton spectator spectrum in the semi-inclusive eD-->e'pX process.

  8. Spreading of thin-film metal patterns deposited on nonplanar surfaces using a shadow mask micromachined in si (110)

    NARCIS (Netherlands)

    Tiggelaar, R.M.; Berenschot, J.W.; Elwenspoek, M.C.; Gardeniers, J.G.E.; Dorsman, R.; Kleijn, C.R.

    2007-01-01

    The application of a three dimensional, self-aligning shadow mask in (110)-oriented silicon for thin-film metal deposition is discussed. This shadow mask is used for the deposition of metal tracks on the bottom of structures with vertical sidewalls, i.e., the patterning of metal catalytic patches un

  9. A Fully Automated Method of Locating Building Shadows for Aerosol Optical Depth Calculations in High-Resolution Satellite Imagery

    Science.gov (United States)

    2010-09-01

    identifying usable shadows and calculating AOD. 11 III. METHODOLOGY An automated approach, based on trigonometry , is created using the shadow technique and...correcting for the offset appears to be the biggest obstacle to implementing this algorithm operationally. 102 THIS PAGE INTENTIONALLY LEFT BLANK

  10. Shadow effects in simulated ultrasound images derived from computed tomography images using a focused beam tracing model

    DEFF Research Database (Denmark)

    Pham, An Hoai; Lundgren, Bo; Stage, Bjarne

    2012-01-01

    Simulation of ultrasound images based on computed tomography (CT) data has previously been performed with different approaches. Shadow effects are normally pronounced in ultrasound images, so they should be included in the simulation. In this study, a method to capture the shadow effects has been...

  11. Policy measure for creating an integrated and brand-focused regional innovation system in tourism in a shadow destination:

    DEFF Research Database (Denmark)

    Brambini, Annalisa; Vang, Jan

    2013-01-01

    Tourism has often been hyped as an engine of regional growth and development but often failed to deliver the expected results. This is especially the case in shadow destinations. The concept of a shadow destination refers to a region whose relative attractioness is significantly lower than co...

  12. Lroc Observations of Permanently Shadowed Regions: Seeing into the Dark

    Science.gov (United States)

    Koeber, S. D.; Robinson, M. S.

    2013-12-01

    Permanently shadowed regions (PSRs) near the lunar poles that receive secondary illumination from nearby Sun facing slopes were imaged by the Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Cameras (NAC). Typically secondary lighting is optimal in polar areas around respective solstices and when the LRO orbit is nearly coincident with the sub-solar point (low spacecraft beta angles). NAC PSR images provide the means to search for evidence of surface frosts and unusual morphologies from ice rich regolith, and aid in planning potential landing sites for future in-situ exploration. Secondary illumination imaging in PSRs requires NAC integration times typically more than ten times greater than nominal imaging. The increased exposure time results in downtrack smear that decreases the spatial resolution of the NAC PSR images. Most long exposure NAC images of PSRs were acquired with exposure times of 24.2-ms (1-m by 40-m pixels, sampled to 20-m) and 12-ms (1-m by 20-m, sampled to 10-m). The initial campaign to acquire long exposure NAC images of PSRs in the north pole region ran from February 2013 to April 2013. Relative to the south polar region, PSRs near the north pole are generally smaller (D6-km were successfully imaged (ex. Whipple, Hermite A, and Rozhestvenskiy U). The third PSR south polar campaign began in April 2013 and will continue until October 2013. The third campaign will expand previous NAC coverage of PSRs and follow up on discoveries with new images of higher signal to noise ratio (SNR), higher resolution, and varying secondary illumination conditions. Utilizing previous campaign images and Sun's position, an individualized approach for targeting each crater drives this campaign. Secondary lighting within the PSRs, though somewhat diffuse, is at low incidence angles and coupled with nadir NAC imaging results in large phase angles. Such conditions tend to reduce albedo contrasts, complicating identification of patchy frost or ice deposits. Within

  13. Transactional Memory

    CERN Document Server

    Harris, Tim; Rajwar, Ravi

    2010-01-01

    The advent of multicore processors has renewed interest in the idea of incorporating transactions into the programming model used to write parallel programs.This approach, known as transactional memory, offers an alternative, and hopefully better, way to coordinate concurrent threads. The ACI(atomicity, consistency, isolation) properties of transactions provide a foundation to ensure that concurrent reads and writes of shared data do not produce inconsistent or incorrect results. At a higher level, a computation wrapped in a transaction executes atomically - either it completes successfullyand

  14. Memory effects in turbulence

    Science.gov (United States)

    Hinze, J. O.

    1979-01-01

    Experimental investigations of the wake flow of a hemisphere and cylinder show that such memory effects can be substantial and have a significant influence on momentum transport. Memory effects are described in terms of suitable memory functions.

  15. Orientation with a Viking sun-compass, a shadow-stick, and two calcite sunstones under various weather conditions.

    Science.gov (United States)

    Bernáth, Balázs; Blahó, Miklós; Egri, Adám; Barta, András; Kriska, György; Horváth, Gábor

    2013-09-01

    It is widely accepted that Vikings used sun-compasses to derive true directions from the cast shadow of a gnomon. It has been hypothesized that when a cast shadow was not formed, Viking navigators relied on crude skylight polarimetry with the aid of dichroic or birefringent crystals, called "sunstones." We demonstrate here that a simple tool, that we call "shadow-stick," could have allowed orientation by a sun-compass with satisfying accuracy when shadows were not formed, but the sun position could have reliably been estimated. In field tests, we performed orientation trials with a set composed of a sun-compass, two calcite sunstones, and a shadow-stick. We show here that such a set could have been an effective orientation tool for Vikings only when clear, blue patches of the sky were visible.

  16. Observation in the MINOS far detector of the shadowing of cosmic rays by the sun and moon

    Energy Technology Data Exchange (ETDEWEB)

    Adamson, P.; /Fermilab; Andreopoulos, C.; /Rutherford /Athens U.; Ayres, D.S.; /Argonne; Backhouse, C.; /Oxford U.; Barr, G.; /Oxford U.; Barrett, W.L.; /Western Washington U.; Bishai, M.; /Brookhaven; Blake, A.; /Cambridge U.; Bock, B.; /Minnesota U., Duluth; Bock, G.J.; /Fermilab; Boehnlein, D.J.; /Fermilab /Fermilab

    2010-08-01

    The shadowing of cosmic ray primaries by the the moon and sun was observed by the MINOS far detector at a depth of 2070 mwe using 83.54 million cosmic ray muons accumulated over 1857.91 live-days. The shadow of the moon was detected at the 5.6 {sigma} level and the shadow of the sun at the 3.8 {sigma} level using a log-likelihood search in celestial coordinates. The moon shadow was used to quantify the absolute astrophysical pointing of the detector to be 0.17 {+-} 0.12{sup o}. Hints of Interplanetary Magnetic Field effects were observed in both the sun and moon shadow.

  17. STRUKTUR DAN PROSES MEMORI

    Directory of Open Access Journals (Sweden)

    Magda Bhinnety

    2015-09-01

    Full Text Available This paper describes structures and processes of human memory system according to the modal model. Sensory memory is described as the first system to store information from outside world. Short‐term memory, or now called working memory, represents a system characterized by limited ability in storing as well as retrieving information. Long‐term memory on the hand stores information larger in amount and longer than short‐term memory

  18. Memory, collective memory, orality and the gospels

    African Journals Online (AJOL)

    Test

    2011-06-07

    Jun 7, 2011 ... with collective memory theory in the works of Halbwachs, Connerton, Gillis, Fentress and. Wickham, Olick, Schwartz ..... critical importance of cultural memory for (re)constructing history. ...... Frankfurt am Main. Baddeley, A.D. ...

  19. Inspecting Shadows of Past Classroom Practices: A Search for Students' Voices

    Science.gov (United States)

    Sullivan, Patricia

    2012-01-01

    Our pedagogical histories lean on textbooks, institutional records, and the words of famous teachers. Students rarely appear in situ. Here, the voices of two very different Progressive Era students cast spotlights on the shadows of long-ago classroom practices--offering a liveliness that is difficult to recover, but worth seeking. (Contains 5…

  20. On the detection of the Moon shadow with the ANTARES neutrino telescope

    Energy Technology Data Exchange (ETDEWEB)

    Distefano, C., E-mail: distefano_c@lns.infn.i [Laboratori Nazionali del Sud INFN, Via S.Sofia 62, 95123 Catania (Italy)

    2011-01-21

    We discuss the possibility of detecting the Moon shadow with the ANTARES neutrino telescope. A detailed Monte Carlo simulation was conducted in order to calculate the expected significance for the measurement. Simulation results show that the ANTARES telescope will be able to observe the effect in a couple of years. Results of the simulation study will be presented and discussed.

  1. On the detection of the Moon shadow with the ANTARES neutrino telescope

    Science.gov (United States)

    Distefano, C.; ANTARES Collaboration

    2011-01-01

    We discuss the possibility of detecting the Moon shadow with the ANTARES neutrino telescope. A detailed Monte Carlo simulation was conducted in order to calculate the expected significance for the measurement. Simulation results show that the ANTARES telescope will be able to observe the effect in a couple of years. Results of the simulation study will be presented and discussed.

  2. Study of the Shadows of the Moon and the Sun with VHE Cosmic Rays

    CERN Document Server

    Atkins, R; Berley, D; Chen, M L; Coyne, D G; Delay, R S; Dingus, B L; Dorfan, D E; Ellsworth, R W; Evans, D; Falcone, A D; Fleysher, L; Fleysher, R; Gisler, G; Goodman, J A; Haines, T J; Hoffman, C M; Hugenberger, S; Kelley, L A; Leonor, I; Macri, J R; McConnell, M; McCullough, J F; McEnery, J E; Miller, R S; Mincer, A I; Morales, M F; Némethy, P; Ryan, J M; Schneider, M; Shen, B; Shoup, A L; Sinnis, G; Smith, A J; Sullivan, G W; Thompson, T N; Tümer, T O; Wang, K; Wascko, M O; Westerhoff, S; Williams, D A; Yang, T; Yodh, G B

    1999-01-01

    Milagrito, a prototype for the Milagro detector, operated for 15 months in 1997-8 and collected 8.9 billion events. It was the first extensive air shower (EAS) array sensitive to showers intiated by primaries with energy below 1 TeV. The shadows of the sun and moon observed with cosmic rays can be used to study systematic pointing shifts and measure the angular resolution of EAS arrays. Below a few TeV, the paths of cosmic rays coming toward the earth are bent by the helio- and geo-magnetic fields. This is expected to distort and displace the shadows of the sun and the moon. The moon shadow, offset from the nominal (undeflected) position, has been observed with high statistical significance in Milagrito. This can be used to establish energy calibrations, as well as to search for the anti-matter content of the VHE cosmic ray flux. The shadow of the sun has also been observed with high significance.

  3. Influence of shadow effect on the strength of steel beams exposed to fire

    DEFF Research Database (Denmark)

    Virdi, Kuldeep; Wickström, Ulf

    2013-01-01

    in or in direct contact with concrete are not considered appropriately - only the reduction of the exposed area is taken into account. In addition, the shadow effect is rarely considered in structures with both concrete and asteel elements such as composite floors. It has been mainly used for stand-alone columns...

  4. The Longitudinal Elderly Person Shadowing Program: Outcomes from an Interprofessional Senior Partner Mentoring Program

    Science.gov (United States)

    Basran, Jenny F. S.; Dal Bello-Haas, Vanina; Walker, Doreen; MacLeod, Peggy; Allen, Bev; D'Eon, Marcel; McKague, Meredith; Chopin, Nicola S.; Trinder, Krista

    2012-01-01

    The University of Saskatchewan's Longitudinal Elderly Person Shadowing (LEPS) is an interprofessional senior mentors program (SMP) where teams of undergraduate students in their first year of medicine, pharmacy, and physiotherapy; 2nd year of nutrition; 3rd year nursing; and 4th year social work partner with community-dwelling older adults.…

  5. Direct Solar Wind Proton Access into Permanently Shadowed Lunar Polar Craters

    Science.gov (United States)

    Zimmerman, M. I.; Farrell, W. M.; Stubbs, T. J.; Halekas, J. S.

    2011-01-01

    Recent analyses of Lunar Prospector neutron spectrometer (LPNS) data have suggested that high abundances of hydrogen exist within cold traps at the lunar poles, and it has often been assumed that hydrogen-bearing volatiles sequestered in permanent shadow are topographically shielded from sputtering by solar wind protons. However, recent simulation results are presented showing that solar wind protons clearly access the floor of an idealized, shadowed lunar crater through a combination of thermal and ambipolar processes, in effect creating a plasma "miniwake". These simulations are the first to model the mini-wake environment in two spatial dimensions with a self-consistent lunar surface-plasma interaction. Progress is reported on constraining the nonzero particle fluxes and energies incident on kilometer-scale shadowed topography, such as a small crater embedded within a larger one. The importance of direct solar wind proton bombardment is discussed within the context of understanding the stability and inventory of hydrogen-bearing volatiles in shadow at the lunar poles. The support of the National Lunar Science institute, the DREAM institute, LPROPS, and the NASA Postdoctoral Program at NASA Goddard Space Flight Center administered by ORAU are gratefully acknowledged.

  6. Shadow effect on photovoltaic potentiality analysis using 3D city models

    NARCIS (Netherlands)

    Alam, N.; Coors, V.; Zlatanova, S.; Van Oosterom, P.J.M.

    2012-01-01

    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 perfor

  7. State Estimation and Forecasting of the Ski-Slope Model Using an Improved Shadowing Filter

    Science.gov (United States)

    Mat Daud, Auni Aslah

    In this paper, we present the application of the gradient descent of indeterminism (GDI) shadowing filter to a chaotic system, that is the ski-slope model. The paper focuses on the quality of the estimated states and their usability for forecasting. One main problem is that the existing GDI shadowing filter fails to provide stability to the convergence of the root mean square error and the last point error of the ski-slope model. Furthermore, there are unexpected cases in which the better state estimates give worse forecasts than the worse state estimates. We investigate these unexpected cases in particular and show how the presence of the humps contributes to them. However, the results show that the GDI shadowing filter can successfully be applied to the ski-slope model with only slight modification, that is, by introducing the adaptive step-size to ensure the convergence of indeterminism. We investigate its advantages over fixed step-size and how it can improve the performance of our shadowing filter.

  8. A Shadow Curriculum: Incorporating Students' Interests into the Formal Biology Curriculum

    Science.gov (United States)

    Hagay, Galit; Baram-Tsabari, Ayelet

    2011-01-01

    Students have been largely ignored in discussions about how best to teach science, and many students feel the curriculum is detached from their lives and interests. This article presents a strategy for incorporating students' interests into the formal Biology curriculum, by drawing on the political meaning of "shadow government" as alternative…

  9. Cloud and Cloud Shadow Masking Using Multi-Temporal Cloud Masking Algorithm in Tropical Environmental

    Science.gov (United States)

    Candra, D. S.; Phinn, S.; Scarth, P.

    2016-06-01

    A cloud masking approach based on multi-temporal satellite images is proposed. The basic idea of this approach is to detect cloud and cloud shadow by using the difference reflectance values between clear pixels and cloud and cloud shadow contaminated pixels. Several bands of satellite image which have big difference values are selected for developing Multi-temporal Cloud Masking (MCM) algorithm. Some experimental analyses are conducted by using Landsat-8 images. Band 3 and band 4 are selected because they can distinguish between cloud and non cloud. Afterwards, band 5 and band 6 are used to distinguish between cloud shadow and clear. The results show that the MCM algorithm can detect cloud and cloud shadow appropriately. Moreover, qualitative and quantitative assessments are conducted using visual inspections and confusion matrix, respectively, to evaluate the reliability of this algorithm. Comparison between this algorithm and QA band are conducted to prove the reliability of the approach. The results show that MCM better than QA band and the accuracy of the results are very high.

  10. Evaluation of Tower Shadowing on Anemometer Measurements at Los Alamos National Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Bruggeman, David Alan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-06-14

    The objective of this study is to evaluate the effect of tower shadowing from the meteorology towers at LANL during 2014. This study is in response to the Department of Energy Meteorological Coordinating Council visit in 2015 that recommended an evaluation of any biases in the wind data introduced by the tower and boom alignment at all meteorology towers.

  11. The Shadow Play: How the Integration of Technology Annihilates Debate in Our Schools.

    Science.gov (United States)

    Burniske, R. W.

    1998-01-01

    Education's greatest threat is the death of dialectics. In Malaysia, government censorship thwarts debate; in America, corporate brainwashing achieves the same result. Consumers have embraced computer technology with too little public discourse. Infatuation with television (screen shadows) distracts people from the puppet master's motives and…

  12. Hybridity in Willa Cather's "Death Comes for the Archbishop" and "Shadows on the Rock"

    Science.gov (United States)

    Fard, Maryam Heydari; Pirnajmuddin, Hossein

    2015-01-01

    Willa Cather wrote "Death Comes for the Archbishop" and "Shadows on the Rock" based on the missionary life of Europeans in Quebec and New Mexico. In both novels she depicts a different type of colonizer-colonized relationship. The colonizers arrive with their stereotypical views about the natives to purportedly civilize them.…

  13. Enhancement Performance of Road Recognition System of Autonomous Robots in Shadow Scenario

    Directory of Open Access Journals (Sweden)

    Olusanya Y. Agunbiade

    2013-12-01

    Full Text Available Road region recognition is a main feature that is g aining increasing attention from intellectuals beca use it helps autonomous vehicle to achieve a successful na vigation without accident. However, different techniques based on camera sensor have been used by various researchers and outstanding results have been achieved. Despite their success, environmental noise like shadow leads to inaccurate recognition of road region which eventually leads to accident for autonomous vehicle. In this research, we conducted an investigation on shadow and its effects, optimized the road region recognition system of autonomous vehicle by introducing an algorithm capable of dete cting and eliminating the effects of shadow. The experimental performance of our system was tested a nd compared using the following schemes: Total Positive Rate (TPR, False Negative Rate (FNR, Tot al Negative Rate (TNR, Error Rate (ERR and False Positive Rate (FPR. The performance result of the system improved on road recognition in shadow scenario and this advancement has added tremendousl y to successful navigation approaches for autonomous vehicle

  14. The evolution of student conceptions of the formation of shadows and images

    NARCIS (Netherlands)

    Rosaroso, N.; van den Berg, E.

    2008-01-01

    The purpose of the study was to "film" the conceptual development of students as they were studying the optics of shadows and mirrors using lesson materials which were developed by the Constructing Physics Understanding (CPU) group of Dr. Fred Goldberg of San Diego State University. The materials we

  15. Shadows, ghosts and chimaeras: on some early modes of handling psycho-genetic heritage.

    Science.gov (United States)

    Durban, Joshua

    2011-08-01

    This paper describes three early developmental modes of handling the individual's psycho-genetic heritage. The first one, which characterizes normal development, is called living with the shadow of one's heritage. The shadow (of history, of life and death) is a natural counterpart of the self. The second mode, which accounts for more disturbed patients, is called living under the shadows of heritage. This type is characterized by an unconscious phantasy of the person being haunted by persecutory and vindictive ghosts instead of benign ancestors. The third mode, which might be encountered in severely disturbed patients, is being the shadow. This mode, called Chimerism, describes a confused organism which may turn against itself as parts of it are experienced as alien. On the unconscious level this signifies a heritage which cannot be experienced or mentalized as such. Rather, it is a complete chaos with moments where the hardly existent self is experienced as a bizarre object made up of non-combining, welded parts. These three modes will be examined with the help of material drawn from two analyses: of an autistic boy and of an adult patient who was persecuted by an unspeakable, horrific ancestral past.

  16. Interprofessional education through shadowing experiences in multi-disciplinary clinical settings

    Directory of Open Access Journals (Sweden)

    Moore Ainsley E

    2010-12-01

    Full Text Available Abstract The World Health Organization has recently added Interprofessional Education (IPE to its global health agenda recognizing it as a necessary component of all health professionals' education. We suggest mandatory interprofessional shadowing experiences as a mechanism to be used by chiropractic institutions to address this agenda. IPE initiatives of other professions (pharmacy and medicine are described along with chiropractic. This relative comparison of professions local to our jurisdiction in Ontario, Canada is made so that the chiropractic profession may take note that they are behind other health care providers in implementing IPE. Interprofessional shadowing experiences would likely take place in a multi-disciplinary clinical setting. We offer an example of how two separate professions within a Family Health Team (FHT can work together in such a setting to enhance both student learning and patient care. For adult learners, using interprofessional shadowing experiences with learner-derived and active objectives across diverse health professional groups may help to improve the educational experience. Mandatory interprofessional shadowing experiences for chiropractors during their training can enhance future collaborative practice and provide success in reaching a goal common to each profession - improved patient care.

  17. Form From Projected Shadow (FFPS): An algorithm for 3D shape analysis of sedimentary particles

    Science.gov (United States)

    Montenegro Ríos, Anibal; Sarocchi, Damiano; Nahmad-Molinari, Yuri; Borselli, Lorenzo

    2013-10-01

    In this paper we present a simple and effective method based on measuring the projected shadow of sedimentary particles by means of a digital image processing algorithm that enables the three principal axes of the particle to be determined from a single 2D color image. The method consists in projecting the shadow of the particle when it is resting on the maximum projection area (“c” axis pointing almost vertical, since in this configuration minimal distance from the center of mass to the floor is achieved minimizing the gravitational potential energy), by means of an oblique incident illumination system. Using HSL (hue-saturation-lightness) color space segmentation, two axes of the particle are measured directly from the maximum projected area. The length of the shadow provides the third axis of the particle. Multiple textured and colored sedimentary particles can be easily segmented from a green background and their corresponding shadows by means of a single space color transformation. This simple method enables the lengths of the three main axes of several particles to be determined at the same time without expensive equipment (the software is provided free by the authors). The axis lengths can span a broad range of sizes, and are measured with low experimental error (less than 5%).

  18. effect of shadowing and multipath fading on the area spectral for cell ...

    African Journals Online (AJOL)

    user

    SPECTRAL FOR CELL-EDGE USERS IN HETEROGENEOUS NETWORKS. M. C. Uko1, M. A. Umoren2,* ... shadowing are major causes of performance degradation in mobile communication systems. .... A Micro/Pico cell is a cell in a mobile phone network ..... Mathodology, and Techniques” Kluwer Academic. Publishers.

  19. Shadow response in the blind cavefish Astyanax reveals conservation of a functional pineal eye.

    Science.gov (United States)

    Yoshizawa, Masato; Jeffery, William R

    2008-02-01

    The blind cavefish Astyanax mexicanus undergoes bilateral eye degeneration during embryonic development. Despite the absence of light in the cave environment, cavefish have retained a structurally intact pineal eye. We show here that contrary to visual degeneration in the bilateral eyes, the cavefish pineal eye has conserved the ability to detect light. Larvae of two different Astyanax cavefish populations and the con-specific sighted surface-dwelling form (surface fish) respond similarly to light dimming by shading the pineal eye. As a response to shading, cavefish larvae swim upward vertically. This behavior resembles that of amphibian tadpoles rather than other teleost larvae, which react to shadows by swimming downward. The shadow response is highest at 1.5-days post-fertilization (d.p.f.), gradually diminishes, and is virtually undetectable by 7.5 d.p.f. The shadow response was substantially reduced after surgical removal of the pineal gland from surface fish or cavefish larvae, indicating that it is based on pineal function. In contrast, removal of one or both bilateral eye primordia did not affect the shadow response. Consistent with its light detecting capacity, immunocytochemical studies indicate that surface fish and cavefish pineal eyes express a rhodopsin-like antigen, which is undetectable in the degenerating bilateral eyes of cavefish larvae. We conclude that light detection by the pineal eye has been conserved in cavefish despite a million or more years of evolution in complete darkness.

  20. Performance Analysis of Amplify-and-Forward Relaying over Shadowed Nakagami-m Fading Channels

    Science.gov (United States)

    Cai, Chunxiao; Cai, Yueming; Yang, Weiwei

    2011-11-01

    In the paper, the closed-form approximation for outage probability and symbol error probability are presented for amplify-and-forward cooperative network over shadowed Nakagami-m Fading Channels. Our results are verified through comparison with Monte Carlo simulations. It shows that our theoretical results can provide good approximations to the numerical results.

  1. Studying Practices of Leading--Qualitative Shadowing in Early Childhood Research

    Science.gov (United States)

    Hognestad, Karin; Bøe, Marit

    2016-01-01

    This article considers qualitative shadowing as a fruitful method to investigate leadership practices. We propose that an approach to practice that takes into account the activities of "sayings, doings and relatings" offers a fresh perspective on how to obtain rich data on practices of leading. The value of this idea is illustrated from…

  2. The evolution of student conceptions of the formation of shadows and images

    NARCIS (Netherlands)

    Rosaroso, N.; van den Berg, E.

    2008-01-01

    The purpose of the study was to "film" the conceptual development of students as they were studying the optics of shadows and mirrors using lesson materials which were developed by the Constructing Physics Understanding (CPU) group of Dr. Fred Goldberg of San Diego State University. The materials we

  3. Surface Water-Ice Deposits in the Northern Shadowed Regions of Ceres

    Science.gov (United States)

    Platz, T.; Nathues, A.; Schorghofer, N.; Preusker, F.; Mazarico, E.; Schroeder, S. E.; Byrne, S.; Kneissl, T.; Schmedemann, N.; Combe, J.-P.; Schaefer, M.; Thangjam, G. S.; Hoffmann, M.; Gutierrez-Marques, P.; Landis, M. E.; Dietrich, W.; Ripken, J.; Matz, K. D.; Russell, C. T.

    2016-01-01

    Ceres, a dwarf planet located in the main asteroid belt, has a low bulk density, and models predict that a substantial amount of water ice is present in its mantle and outer shell. The Herschel telescope and the Dawn spacecraft have observed the release of water vapor from Ceres, and exposed water ice has been detected by Dawn on its surface at mid-latitudes. Water molecules from endogenic and exogenic sources can also be cold-trapped in permanent shadows at high latitudes, as happens on the Moon and Mercury. Here we present the first image-based survey of Ceres's northern permanent shadows and report the discovery of bright deposits in cold traps. We identify a minimum of 634 permanently shadowed craters. Bright deposits are detected on the floors of just 10 of these craters in multiscattered light. We spectroscopically identify one of the bright deposits as water ice. This detection strengthens the evidence that permanently shadowed areas have preserved water ice on airless planetary bodies.

  4. The Impact of Prestige Orientation on Shadow Education in South Korea

    Science.gov (United States)

    Lee, Soojeong; Shouse, Roger C.

    2011-01-01

    Widespread use of "shadow education" is a major policy issue in East Asia, especially South Korea, where officials view it as harmful to educational and fiscal equity. Although previous research emphasizes functional explanations, this study takes an institutional approach, exploring how students' desire for prestigious matriculation…

  5. Shadow Scholars and the Rise of the Dissertation Service Industry: Can We Maintain Academic Integrity?

    Science.gov (United States)

    White, Jeffry L.

    2016-01-01

    Notable interest was generated when Dave Tomar's book, "The Shadow Scholar: How I Made a Living Helping College Kids Cheat," was first published. While ghostwriters and paper mills have long been part of the academic landscape, a far more ominous enterprise has appeared that targets master's and doctoral students seeking assistance with…

  6. Social capital as a determinant of the shadow economy in the Republic of Serbia

    Directory of Open Access Journals (Sweden)

    Natasa Golubovic

    2015-08-01

    Full Text Available The design and implementation of the measures aimed at incorporating informal economic activities into the existing formal regulatory framework assume the knowledge of the causes and structure of the informal activity. The influence of the institutional factors that encourage the development of the shadow economy (the tax burden, the degree of the regulation of the economy, the capacity of the state administration were the subject of extensive theoretical and empirical research. In contrast, the impact of social capital, i.e. the characteristics of social ties and relations, on the shadow economy has been investigated to a much lesser extent. Starting from the fact that the informal sector of the Serbian economy is so widespread that it represents a serious obstacle to the business activities of Serbian enterprises, the aim of this study is to investigate whether the characteristics of social ties and relations, or social capital in the Republic of Serbia (RS, represent a fertile ground for the growth of the shadow economy. In this context, the characteristics and frequency of social contacts, particularized trust and institutional trust will be separately analyzed as the determinants of the shadow economy in RS.

  7. In the shadow of good governance : an ethnography of civil service reform in Africa

    NARCIS (Netherlands)

    Anders, Gerhard

    2010-01-01

    In the shadow of good governance traces the implementation of the good governance agenda in Malawi from the loan documents signed by the representatives of the governement and the Bretton Woods institutions to the individual experiences of civil servants who responded in unforeseen ways to the refor

  8. Parent explanation and preschoolers’ exploratory behavior and learning in a shadow exhibition

    NARCIS (Netherlands)

    van Schijndel, T.J.P.; Raijmakers, M.E.J.

    2016-01-01

    The present study fills a gap in existing visitor research by focusing on the preschool age group. The study explores relationships between parent explanation, children's exploratory behavior, and their domain-specific learning in a shadow exhibition. In addition, the effect of a preceding theater s

  9. Studying Practices of Leading--Qualitative Shadowing in Early Childhood Research

    Science.gov (United States)

    Hognestad, Karin; Bøe, Marit

    2016-01-01

    This article considers qualitative shadowing as a fruitful method to investigate leadership practices. We propose that an approach to practice that takes into account the activities of "sayings, doings and relatings" offers a fresh perspective on how to obtain rich data on practices of leading. The value of this idea is illustrated from…

  10. The Shadow Knows: Inferring the Density Distribution of a Nonuniform Medium from Its Standing Wave Pattern

    Science.gov (United States)

    Binder, Philippe; Cunnyngham, Ian

    2012-01-01

    In a recent note in this journal, Gluck presents a beautiful demonstration of the standing wave generated by a strip of material with linearly varying width (a trapezoid). As expected, the resulting wave envelope (and its shadow) showed a varying wavelength--smaller as the strip width gets larger.

  11. Solar array design based on shadow analysis for increasing net energy collection in a competition vehicle

    Science.gov (United States)

    Osorio-Gómez, Gilberto; Mejía-Gutiérrez, Ricardo; Suárez-Castañeda, Nicolás; Gil-Herrera, Ana; Barrera-Velásquez, Jorge

    2015-01-01

    Photovoltaic (PV) applications such as in the architectural, automotive, and aerospace industries face design contradictions because they are expected to produce a lot of energy but are constrained by available area, surface shape, incident irradiance, shadows, and other aspects that have a negative influence on the energy produced by the solar panel. Solar competition vehicles are some of these challenging PV applications. The design of such solar arrays needs to consider efficiency evaluation in order to optimize space; it is difficult not to install solar modules in areas impacted by shadows. A design procedure for a solar array configuration based on shadow analysis for competition vehicles is presented. The principle is that shadows in moving objects can be simulated, since the vehicle, the earth and the sun are are moving in semipredictable patterns, thus net energy collection can be forecast. The case study presented is the solar array design of a vehicle that participated in the World Solar Challenge 2013. The obtained results illustrate how the employment of the procedure gives insights on important aspects to consider and also delivers qualitative and quantitative information for decision making. In addition, the experience in competition highlights some issues to be considered, modified, or improved in further vehicle designs.

  12. Measurement of eye size illusion caused by eyeliner, mascara, and eye shadow.

    Science.gov (United States)

    Matsushita, Soyogu; Morikawa, Kazunori; Yamanami, Haruna

    2015-01-01

    Do eyeliner, mascara, and eye shadow actually make the eyes appear larger than they really are? If so, by what percentage? To answer these questions, we used psychophysical experiments. Experiment 1 manipulated the degree of eyeliner (four levels) and mascara (five levels), and measured perceived eye size using a psychophysical procedure called the staircase method. The results showed that both eyeliner and mascara make the eyes appear larger than they really are by up to 6% (13% in area), but their effects are not additive. Eyeliner increased perceived eye size only in the absence of mascara. In the presence of mascara, however, eyeliner has no additional effect. Experiment 2 measured perceived eye size with or without eye shadow and demonstrated that eye shadow increases perceived eye size by about 5% (10% in area). These findings indicate that one mechanism by which makeup and cosmetics alter facial appearances involves inducing visual illusions. In addition, it is suggested that the eye size illusion caused by eyeliner, mascara, and eye shadow uses the same mechanism as that of the Delboeuf illusion, a geometric illusion of assimilation.

  13. Correcting the relationship between PRI and shadow fraction for the blue sky effect

    Science.gov (United States)

    Mõttus, Matti

    2016-04-01

    The Photochemical Reflectance Index (PRI) is defined as the normalized difference ratio of leaf reflectance at two specific wavelengths in the green spectral region. Its value depends on the status of leaf carotenoid content, and especially that of the xanthophyll cycle pigments. Due to the dependence on the xanthophyll cycle, when the photosynthetic apparatus of green leaves is close to the saturation limit, their PRI becomes dependent on light conditions. Therefore, by measuring the PRI of leaves in the same canopy under different local irradiance conditions on a sunny day, it should be possible to determine the saturation level of the leaves. In turn, this gives information on the light use efficiency (LUE) of the vegetation canopy. The average light conditions of visible foliage elements are often quantified with the shadow fraction -- the fraction of visible foliage not lit by direct sunlight. The dependence of PRI on the shadow fraction has been used to remotely measure canopy LUE on clear days. Variations in shadow fraction have been achieved with multiangular measurement. However, besides photosynthetic downregulation, the dependence of canopy PRI on shadow fraction is affected by the blue sky radiation caused by scattering in the atmosphere. To quantify this effect on remotely sensed PRI, we present the underlying definitions relating leaf and canopy PRI and perform the required calculations for typical midsummer conditions in Central Finland. We demonstrate that the effect of blue sky radiation on the variation of PRI with canopy shadow fraction is similar in shape and magnitude to that of LUE variations reported in literature. Next, we propose a new method to assess these PRI variations in structured vegetation. We investiagate this blue sky effect on the PRI -- shadow fraction relationship with high spatial (60 cm) and spectral (9.8 nm) resolution airborne imaging spectroscopy data from Hyytiälä, Finland. We evaluate the spectral irradiance in

  14. Microscopic air void analysis of hardened Portland cement concrete by the isolated shadow technique

    Science.gov (United States)

    Harris, Basil Mark

    The Isolated Shadow Technique is an image processing and analysis procedure for identifying and characterizing surface voids dispersed on an otherwise flat plane of heterogeneous solids. The objective of the Isolated Shadow Technique is to capture, process, and analyze images of a flat surface in which all of the features, save the boundary outlines of any surface voids, are eliminated. In short, the technique utilizes a series of digital images of the subject planar surface; where each image of the series is subjected to a unique lighting condition. By positioning the lights such that the shadows cast into the craters vary between images, these variations can be sequestered and the edges of the voids can subsequently be reconstructed from the isolated shadows. The primary purpose of this work was the development of the Isolated Shadow Technique for the particular application of quantitatively describing the microscopic voids in hardened Portland cement concrete. The Isolated Shadow System was developed for this application of the technique. The hardware and software of the system are described and the function is demonstrated. The system was found to have an average accuracy of 2.7% with a maximum deviation of 5.0% when compared to physical measurements. The results of polished sections of concrete specimens characterized by the Isolated Shadow System are compared to the results obtained with the commonly used standard methods (ASTM C 457; A and B). The coefficients of variation of parameters calculated to describe the air-void system (according to the ASTM C 457 formulations) are shown to be in the neighborhood of one percent when the observed test area includes at least 7,830 mmsp2 of polished concrete (with paste contents ranging from approximately 28% to 32%). The sensitivity of the air-void system parameters (as computed by the system) to changes in magnification and mosaic size are evaluated. A critical analysis of the underlying assumptions of the ASTM C

  15. Optical memory

    Science.gov (United States)

    Mao, Samuel S; Zhang, Yanfeng

    2013-07-02

    Optical memory comprising: a semiconductor wire, a first electrode, a second electrode, a light source, a means for producing a first voltage at the first electrode, a means for producing a second voltage at the second electrode, and a means for determining the presence of an electrical voltage across the first electrode and the second electrode exceeding a predefined voltage. The first voltage, preferably less than 0 volts, different from said second voltage. The semiconductor wire is optically transparent and has a bandgap less than the energy produced by the light source. The light source is optically connected to the semiconductor wire. The first electrode and the second electrode are electrically insulated from each other and said semiconductor wire.

  16. Shadows and Silence: Analysis of Social and Environmental Reports of the Energy Sector

    Directory of Open Access Journals (Sweden)

    Fabrício do Nascimento Moreira

    2016-04-01

    Full Text Available While it is acknowledged that there has been a rapid growth in the disclosure of social and environmental responsibility reports of companies, it is assumed also that there is a long way to go in that these reports meet their users, stakeholders, considering the characteristics of materiality, consistency, integrity and accountability in the construction of accounting information. So with the need to advance this discussion, some scholars in the field of environmental accounting began to suggest, among other ideas, building models formed by basic reporting accounts silence and shadow, they could identify differences between perceived environmental performance the public interested in the activities and affairs of the entity and performance that corporations claim they have achieved through their accounts and reports publicly available. While the report is constructed from silent speech, vision and corporate positioning, the second shadow report, part of the stakeholder perspective, i.e., the desires of stakeholders in the activities and business of the company. The objective of the study is to explore if the preparation of shadow and silent report can contribute to the improvement of the information quality of corporate environmental performance reports. To achieve this goal, it was prepared the silent and shadow reports of ELETROBRAS system and later confronted. It was found that companies have trouble to expose negative social and environmental impacts in reports; the volume of news published on corporate websites is not as significant as shown by other studies and the companies, over the years, didn’t publish the reports in a regular basis and with the same pattern; among other findings. Finally, it was concluded that the shadow and silent reports could be used to improve the information quality in corporate environmental performance reports.

  17. Quantifying the effect of magnetopause shadowing on electron radiation belt dropouts

    Science.gov (United States)

    Yu, Y.; Koller, J.; Morley, S. K.

    2013-11-01

    Energetic radiation belt electron fluxes can undergo sudden dropouts in response to different solar wind drivers. Many physical processes contribute to the electron flux dropout, but their respective roles in the net electron depletion remain a fundamental puzzle. Some previous studies have qualitatively examined the importance of magnetopause shadowing in the sudden dropouts either from observations or from simulations. While it is difficult to directly measure the electron flux loss into the solar wind, radial diffusion codes with a fixed boundary location (commonly utilized in the literature) are not able to explicitly account for magnetopause shadowing. The exact percentage of its contribution has therefore not yet been resolved. To overcome these limitations and to determine the exact contribution in percentage, we carry out radial diffusion simulations with the magnetopause shadowing effect explicitly accounted for during a superposed solar wind stream interface passage, and quantify the relative contribution of the magnetopause shadowing coupled with outward radial diffusion by comparing with GPS-observed total flux dropout. Results indicate that during high-speed solar wind stream events, which are typically preceded by enhanced dynamic pressure and hence a compressed magnetosphere, magnetopause shadowing coupled with the outward radial diffusion can explain about 60-99% of the main-phase radiation belt electron depletion near the geosynchronous orbit. While the outer region (L* > 5) can nearly be explained by the above coupled mechanism, additional loss mechanisms are needed to fully explain the energetic electron loss for the inner region (L* ≤ 5). While this conclusion confirms earlier studies, our quantification study demonstrates its relative importance with respect to other mechanisms at different locations.

  18. The stress shadow induced by the 1975-1984 Krafla rifting episode

    KAUST Repository

    Maccaferri, F.

    2013-03-01

    It has been posited that the 1975–1984 Krafla rifting episode in northern Iceland was responsible for a significant drop in the rate of earthquakes along the Húsavík-Flatey Fault (HFF), a transform fault that had previously been the source of several magnitude 6–7 earthquakes. This compelling case of the existence of a stress shadow has never been studied in detail, and the implications of such a stress shadow remain an open question. According to rate-state models, intense stress shadows cause tens of years of low seismicity rate followed by a faster recovery phase of rate increase. Here, we compare the long-term predictions from a Coulomb stress model of the rifting episode with seismological observations from the SIL catalog (1995–2011) in northern Iceland. In the analyzed time frame, we find that the rift-induced stress shadow coincides with the eastern half of the fault where the observed seismicity rates are found to be significantly lower than expected, given the historical earthquake activity there. We also find that the seismicity rates on the central part of the HFF increased significantly in the last 17 years, with the seismicity progressively recovering from west to east. Our observations confirm that rate-state theory successfully describes the long-term seismic rate variation during the reloading phase of a fault invested by a negative Coulomb stress. Coincident with this recovery, we find that the b-value of the frequency-magnitude distribution changed significantly over time. We conclude that the rift-induced stress shadow not only decreased the seismic rate on the eastern part of the HFF but also temporarily modified how the system releases seismic energy, with more large magnitude events in proportion to small ones. This behavior is currently being overturned, as rift-induced locking is now being compensated by tectonic forcing.

  19. Horizon structure of rotating Einstein-Born-Infeld black holes and shadow

    Energy Technology Data Exchange (ETDEWEB)

    Atamurotov, Farruh [Institute of Nuclear Physics, Tashkent (Uzbekistan); Inha University in Tashkent, Tashkent (Uzbekistan); Ulugh Beg Astronomical Institute, Tashkent (Uzbekistan); National University of Uzbekistan, Tashkent (Uzbekistan); Ghosh, Sushant G. [Jamia Millia Islamia, Centre for Theoretical Physics, New Delhi (India); University of Kwa-Zulu-Natal, Astrophysics and Cosmology Research Unit, School of Mathematical Sciences, Private Bag 54001, Durban (South Africa); Ahmedov, Bobomurat [Institute of Nuclear Physics, Tashkent (Uzbekistan); Ulugh Beg Astronomical Institute, Tashkent (Uzbekistan); National University of Uzbekistan, Tashkent (Uzbekistan)

    2016-05-15

    We investigate the horizon structure of the rotating Einstein-Born-Infeld solution which goes over to the Einstein-Maxwell's Kerr-Newman solution as the Born-Infeld parameter goes to infinity (β → ∞). We find that for a given β, mass M, and charge Q, there exist a critical spinning parameter a{sub E} and r{sub H}{sup E}, which corresponds to an extremal Einstein-Born-Infeld black hole with degenerate horizons, and a{sub E} decreases and r{sub H}{sup E} increases with increase of the Born-Infeld parameter β, while a < a{sub E} describes a non-extremal Einstein-Born-Infeld black hole with outer and inner horizons. Similarly, the effect of β on the infinite redshift surface and in turn on the ergo-region is also included. It is well known that a black hole can cast a shadow as an optical appearance due to its strong gravitational field. We also investigate the shadow cast by the both static and rotating Einstein-Born-Infeld black hole and demonstrate that the null geodesic equations can be integrated, which allows us to investigate the shadow cast by a black hole which is found to be a dark zone covered by a circle. Interestingly, the shadow of an Einstein-Born-Infeld black hole is slightly smaller than for the Reissner-Nordstrom black hole, which consists of concentric circles, for different values of the Born-Infeld parameter β, whose radius decreases with increase of the value of the parameter β. Finally, we have studied observable distortion parameter for shadow of the rotating Einstein-Born-Infeld black hole. (orig.)

  20. OBJECT BASED AGRICULTURAL LAND COVER CLASSIFICATION MAP OF SHADOWED AREAS FROM AERIAL IMAGE AND LIDAR DATA USING SUPPORT VECTOR MACHINE

    Directory of Open Access Journals (Sweden)

    R. T. Alberto

    2016-06-01

    Full Text Available Aerial image and LiDAR data offers a great possibility for agricultural land cover mapping. Unfortunately, these images leads to shadowy pixels. Management of shadowed areas for classification without image enhancement were investigated. Image segmentation approach using three different segmentation scales were used and tested to segment the image for ground features since only the ground features are affected by shadow caused by tall features. The RGB band and intensity were the layers used for the segmentation having an equal weights. A segmentation scale of 25 was found to be the optimal scale that will best fit for the shadowed and non-shadowed area classification. The SVM using Radial Basis Function kernel was then applied to extract classes based on properties extracted from the Lidar data and orthophoto. Training points for different classes including shadowed areas were selected homogeneously from the orthophoto. Separate training points for shadowed areas were made to create additional classes to reduced misclassification. Texture classification and object-oriented classifiers have been examined to reduced heterogeneity problem. The accuracy of the land cover classification using 25 scale segmentation after accounting for the shadow detection and classification was significantly higher compared to higher scale of segmentation.

  1. Memory and Study

    Institute of Scientific and Technical Information of China (English)

    沈园

    1996-01-01

    Of all the myths that surround memory, the most damaging is that it is agift. That is quite untrue. Memory is a skill; and like any skill its performancedepends on application, on practice, and on regular training. Everyone poten-tially has a first-class memory; and everyone can train their memory, and there-

  2. Memory, microprocessor, and ASIC

    CERN Document Server

    Chen, Wai-Kai

    2003-01-01

    System Timing. ROM/PROM/EPROM. SRAM. Embedded Memory. Flash Memories. Dynamic Random Access Memory. Low-Power Memory Circuits. Timing and Signal Integrity Analysis. Microprocessor Design Verification. Microprocessor Layout Method. Architecture. ASIC Design. Logic Synthesis for Field Programmable Gate Array (EPGA) Technology. Testability Concepts and DFT. ATPG and BIST. CAD Tools for BIST/DFT and Delay Faults.

  3. Evaluation of Pan-Sharpening Methods for Automatic Shadow Detection in High Resolution Images of Urban Areas

    Science.gov (United States)

    de Azevedo, Samara C.; Singh, Ramesh P.; da Silva, Erivaldo A.

    2017-04-01

    Finer spatial resolution of areas with tall objects within urban environment causes intense shadows that lead to wrong information in urban mapping. Due to the shadows, automatic detection of objects (such as buildings, trees, structures, towers) and to estimate the surface coverage from high spatial resolution is difficult. Thus, automatic shadow detection is the first necessary preprocessing step to improve the outcome of many remote sensing applications, particularly for high spatial resolution images. Efforts have been made to explore spatial and spectral information to evaluate such shadows. In this paper, we have used morphological attribute filtering to extract contextual relations in an efficient multilevel approach for high resolution images. The attribute selected for the filtering was the area estimated from shadow spectral feature using the Normalized Saturation-Value Difference Index (NSVDI) derived from pan-sharpening images. In order to assess the quality of fusion products and the influence on shadow detection algorithm, we evaluated three pan-sharpening methods - Intensity-Hue-Saturation (IHS), Principal Components (PC) and Gran-Schmidt (GS) through the image quality measures: Correlation Coefficient (CC), Root Mean Square Error (RMSE), Relative Dimensionless Global Error in Synthesis (ERGAS) and Universal Image Quality Index (UIQI). Experimental results over Worldview II scene from São Paulo city (Brazil) show that GS method provides good correlation with original multispectral bands with no radiometric and contrast distortion. The automatic method using GS method for NSDVI generation clearly provide a clear distinction of shadows and non-shadows pixels with an overall accuracy more than 90%. The experimental results confirm the effectiveness of the proposed approach which could be used for further shadow removal and reliable for object recognition, land-cover mapping, 3D reconstruction, etc. especially in developing countries where land use and

  4. Non-volatile memories

    CERN Document Server

    Lacaze, Pierre-Camille

    2014-01-01

    Written for scientists, researchers, and engineers, Non-volatile Memories describes the recent research and implementations in relation to the design of a new generation of non-volatile electronic memories. The objective is to replace existing memories (DRAM, SRAM, EEPROM, Flash, etc.) with a universal memory model likely to reach better performances than the current types of memory: extremely high commutation speeds, high implantation densities and retention time of information of about ten years.

  5. Verbal memory and menopause.

    Science.gov (United States)

    Maki, Pauline M

    2015-11-01

    Midlife women frequently report memory problems during the menopausal transition. Recent studies validate those complaints by showing significant correlations between memory complaints and performance on validated memory tasks. Longitudinal studies demonstrate modest declines in verbal memory during the menopausal transition and a likely rebound during the postmenopausal stage. Clinical studies that examine changes in memory following hormonal withdrawal and add-back hormone therapy (HT) demonstrate that estradiol plays a critical role in memory. Although memory changes are frequently attributed to menopausal symptoms, studies show that the memory problems occur during the transition even after controlling for menopausal symptoms. It is well established that self-reported vasomotor symptoms (VMS) are unrelated to objective memory performance. However, emerging evidence suggests that objectively measured VMS significantly correlate with memory performance, brain activity during rest, and white matter hyperintensities. This evidence raises important questions about whether VMS and VMS treatments might affect memory during the menopausal transition. Unfortunately, there are no clinical trials to inform our understanding of how HT affects both memory and objectively measured VMS in women in whom HT is indicated for treatment of moderate to severe VMS. In clinical practice, it is helpful to normalize memory complaints, to note that evidence suggests that memory problems are temporary, and to counsel women with significant VMS that memory might improve with treatment.

  6. Determining shape of a seasonally shadowed asteroid using stellar occultation imaging

    Science.gov (United States)

    Murchie, Scott L.; Nair, Hari; Stephens, Grant K.

    2016-10-01

    A key objective in exploration of small, asteroidal bodies is to determine global shape and volume. The accuracy to which volume can be determined limits determination of bulk density, an important measurement for understanding internal structure. A special case for a rendezvous mission that uses stereo imaging to determine shape is a body with high obliquity encountered near solstice: half of the body is in shadow, and imaging of illuminated terrain alone under-constrains global shape. In this paper we demonstrate the use of stellar occultation imaging to place an upper bound on volume of such a shadowed hemisphere. Thirty-three sets of images of the night side limb of Mercury, acquired by the Mercury Dual Imaging System (MDIS) wide-angle camera (WAC) on MESSENGER, were used to bound the radius of that planet's night side. The maximum radius determined from this limited image set agrees with the actual radius to within ~0.1%. We show, by simulation, expected performance of a campaign of such night side limb images to bound the shape of an irregular, high-obliquity asteroid encountered at solstice. We assumed a body the size and shape of Deimos imaged from a 40-km radius orbit by an imager having specifications of the MDIS/WAC but an updated detector sensitive to mv~10 stars, and a day-side stereo imaging campaign by a well-calibrated camera system. From an equatorial orbit, with one hemisphere in shadow, a campaign of ≥150 night side limb images determines volume of the shadowed hemisphere to ~4 to 6% accuracy. Increasing orbital inclination to improve sampling of high latitudes decreases residuals for the dark hemisphere by 2 to 3%, for the same number of images. A ~2 to 3% uncertainty in global volume - from stereo imaging of illuminated terrain and stellar occultation imaging of shadowed terrain - compares favorably to uncertainty of up to ±25% in the absence of direct measurements of the radius of the shadowed hemisphere.

  7. Salam Memorial

    CERN Document Server

    Rubbia, Carlo

    1997-01-01

    by T.W.B. KIBBLE / Blackett Laboratory, Imperial College, London. Recollections of Abdus Salam at Imperial College I shall give a personal account of Professor Salam's life and work from the perspective of a colleague at Imperial College, concentrating particularly but not exclusively on the period leading up to the discovery of the electro-weak theory. If necessary I could perhaps give more detail, but only once I have given more thought to what ground I shall cover. by Sheldon Lee GLASHOW / Harvard University, Cambridge, MA, USA. Memories of Abdus Salam. My interactions with Abdus Salam, weak as they have been, extended over five decades. I regret that we never once collaborated in print or by correspondence. I visited Abdus only twice in London and twice again in Trieste, and met him at the occasional conference or summer school. Our face-to-face encounters could be counted on one's fingers and toes, but we became the best of friends. Others will discuss Abdus as an inspiring teacher, as a great scientist,...

  8. From the Generation Memory to the Group Identity: The Film "A Throat Full of Strawberries"

    Directory of Open Access Journals (Sweden)

    Nataša Delač

    2015-09-01

    Full Text Available In the work entitled “From the generation memory to the group identity: the film "A Throat Full of Strawberries", the influence of personal and collective memory on generation identity is analyzed. The work is based on Jan Assmann and Aleida Assmann’s theory of memory, with a special review of the books “Cultural Memory” (Jan Assmann, and “Work on the National Memory” and “The Long Shadow of the Past” (Aleida Assmann. Firstly, the analysis includes the mapping, then the explanation of the memory figures which appear in the movie. Also, the thesis which I covered in the work refers to the difference between Halbwachs’s  term “the images of memory”, and “the figure of memory” introduced by Assmann: the figures of memory are complementary to the first term “because they include not only pictorial, but narrative forms as well.” (Assmann. In this paper, the relation between personal and collective memory is examined, as well as how individual memory influences the establishment of one’s group memory, and how memory and remembrance affect what we call generation identity. The Film “A Throat Full of Strawberries” (by Srdjan Karanovic, 1985 was chosen as my case study. This movie is a sequel to the series “The Unpicked Strawberries” (Srdjan Karanovic, 1976. It tells about a reunion of the group of people of the particular generation, who evoke the memories about the events during the 60’s (the time of their youth, so the topic this film is focused on represents the starting point for the study of the generation memory and its function. The aim of this paper is to prove that generation memory has the crucial role when it comes to the creation of one’s group identity

  9. Is the Memory Effect of the Blind Spot Involved in Negative Dysphotopsia after Cataract Surgery?

    Science.gov (United States)

    Wenzel, Martin; Menapace, Rupert; Eppig, Timo; Langenbucher, Achim

    2015-01-01

    We present novel clinical observations on negative dysphotopsia (ND) in eyes that have undergone cataract surgery. In the past, shadow effects were alleged to be located in the far peripheral temporal visual field 50° to 100° away from the optical axis. In a small series of eight patients we found evidence of photic effects, described by the patients as shadows in the periphery that were objectively located much more centrally. In all cases, we could find an association of these phenomena with the blind spot. We hypothesize that the memory effect of the blind spot which is dislocated and changed in magnification due to replacement of the crystalline lens could be one determinant for pseudophakic ND. The scotoma of the optic nerve head and the main arteries and veins of the phakic eye are displaced in the pseudophakic eye depending on the specific characteristics and position of the intraocular lens within the eye. PMID:26425353

  10. Is the Memory Effect of the Blind Spot Involved in Negative Dysphotopsia after Cataract Surgery?

    Directory of Open Access Journals (Sweden)

    Martin Wenzel

    2015-01-01

    Full Text Available We present novel clinical observations on negative dysphotopsia (ND in eyes that have undergone cataract surgery. In the past, shadow effects were alleged to be located in the far peripheral temporal visual field 50° to 100° away from the optical axis. In a small series of eight patients we found evidence of photic effects, described by the patients as shadows in the periphery that were objectively located much more centrally. In all cases, we could find an association of these phenomena with the blind spot. We hypothesize that the memory effect of the blind spot which is dislocated and changed in magnification due to replacement of the crystalline lens could be one determinant for pseudophakic ND. The scotoma of the optic nerve head and the main arteries and veins of the phakic eye are displaced in the pseudophakic eye depending on the specific characteristics and position of the intraocular lens within the eye.

  11. Organizational memory: from expectations memory to procedural memory

    NARCIS (Netherlands)

    Ebbers, J.J.; Wijnberg, N.M.

    2009-01-01

    Organizational memory is not just the stock of knowledge about how to do things, but also of expectations of organizational members vis-à-vis each other and the organization as a whole. The central argument of this paper is that this second type of organizational memory -organizational expectations

  12. Organizational memory: from expectations memory to procedural memory

    NARCIS (Netherlands)

    Ebbers, J.J.; Wijnberg, N.M.

    2009-01-01

    Organizational memory is not just the stock of knowledge about how to do things, but also of expectations of organizational members vis-à-vis each other and the organization as a whole. The central argument of this paper is that this second type of organizational memory -organizational expectations

  13. Exploring history and memory through autobiographical memory

    Directory of Open Access Journals (Sweden)

    Ivor Goodson

    2015-02-01

    Full Text Available The article reviews the role of autobiographical memory as a site of narrative construction. Far from being a place of liberal retrospective recall it is a site of active recapitulation and reconstruction. The article provides examples of how history and memory are intermingled. It also draws in the author’s autobiographical vignettes to explore the underpinning desires for historical reconstruction in autobiographical memory work

  14. Chile shadow report to the United Nations sheds light on women's rights.

    Science.gov (United States)

    Farmer, A

    1999-07-01

    Three Chilean women's rights organizations and CRLP presented a Shadow Report to the UN Committee on the Elimination of All Forms of Discrimination Against Women (CEDAW). The 25-page Shadow Report indicates in summary the disappointment of the Chilean women in their government. Although Chile has emerged from its history of military dictatorship and is taking its first steps toward returning to a democratic-style of government, the military and the Catholic Church still exert a very strong influence, especially when it comes to policy making. Chilean people especially women, continue to be tyrannized by repressive attitudes, laws, and policies. This tyrannization is exemplified by the rampant discrimination against women in the prisons and the punishment of those undergoing illegal abortions. In short, women have no rights in Chile, and the government has not done enough to eliminate discrimination against them.

  15. In the Shadow of the State - the Informal Economy and Informal Economy Labor Force

    Directory of Open Access Journals (Sweden)

    Schneider Friedrich

    2015-02-01

    Full Text Available In this paper, the main focus lies on the informal economy and on work in the shadow. The most influential factors on the informal economy are tax policies and state regulation. The size of the informal economy was decreasing over the period 1999 to 2007, from 34.0% to 31.2% for 161 countries (unweighted average. Furthermore, economic opportunities, taxes and regulations, the general situation on the labor market, and unemployment are crucial for an understanding of the dynamics of the shadow labor force. In contrast with the decrease of the informal economy (value added figures, the informal economy labor force increased for most countries over the period 1999 to 2007.

  16. Sensitivity analysis on chaotic dynamical system by Non-Intrusive Least Square Shadowing (NILSS)

    CERN Document Server

    Ni, Angxiu

    2016-01-01

    This paper develops the tangent Non-Intrusive Least Square Shadowing (NILSS) method, which computes sensitivity for chaotic dynamical systems. In NILSS, a tangent solution is represented as a linear combination of a inhomogeneous tangent solution and some homogeneous tangent solutions. Then we solve a least square problem under this new representation. As a result, this new variant is easier to implement with existing solvers. For chaotic systems with large degrees of freedom but low dimensional attractors, NILSS has low computation cost. NILSS is applied to two chaotic PDE systems: the Lorenz 63 system, and a CFD simulation of a backward-facing step. The results show that NILSS computes the correct derivative with a lower cost than the conventional Least Square Shadowing method and the conventional finite difference method.

  17. Lights in the shadows: Florence Nightingale and others who made their mark.

    Science.gov (United States)

    Stanley, David

    2007-02-01

    Florence Nightingale, the 'lady with the lamp' became the image of 'heroic womanhood' (Bostridge 2004) when she returned from the Crimean War an iconic figure and ever since she has remained fated to wear the mantel of nursings' leading light. But she wasn't the only woman who made their mark or who undertook to risk their live caring for the sick and injured, wounded and dying in the Crimea. Sadly, Nightingale's iconic status has also succeeded in overshadowing the existence and the achievements of the many others who nursed during the Crimean war. These women, nuns, ordinary nurses, lady volunteers and others, working in Nightingale's shadow, contributed much to the comforts of the wounded and dying and this article seeks to illuminate their presence and contribution. It also highlights other aspects of Nightingale's work and in doing so, allows us to look into the shadows and shed more light on the others who were also there.

  18. Social learning in the Anthropocene: Novel challenges, shadow networks, and ethical practices.

    Science.gov (United States)

    Schmidt, Jeremy J

    2017-05-15

    The Anthropocene presents novel challenges for environmental management. This paper considers the challenges that the Anthropocene poses for social learning techniques in adaptive management. It situates these challenges with respect to how anthropogenic forcing on the Earth system affects the conditions required for: (1) The cooperative exercises of social learning; (2) The techniques used for assessing the fit of institutions to social-ecological systems; and, (3) The strategies employed for identifying management targets that are transformed by human action. In view of these challenges, the paper then examines how the practices of shadow networks may provide paths for incorporating a broader, more robust suite of social learning practices in the Anthropocene. The paper emphasizes how novel challenges in the Anthropocene demand increased attention to ethical practices, particularly those that establish center-periphery relationships between social learning communities and shadow networks. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Developing an Android Based Application as Balinese Shadow Puppet Educational Media

    Directory of Open Access Journals (Sweden)

    Gede Doni Agustina

    2017-04-01

    Full Text Available Instead of being a barrier in preserving the culture, the development of technology is supposed to be an effective strategy of cultural preservation and protection. Modern and update technology provides an effective media of culture campaign. This study presented the development process of an android based Balinese shadow puppet educational media as both an effective learning media and a strategy to preserve Balinese shadow puppet. This study was categorized as research and development. The media was developed by using waterfall model and implemented by using the Lua Programming language with editor and Corona SDK simulator.  The collected data were the users’ response to the developed media resulted from questionnaires. The user’s response to the media was categorized as positive. Based on the results of this study, the media were equipped with well operated features and functions and user friendly interface.

  20. THE OBJECTIFICATION OF DEFINITION OF THE PURCHASING POWER OF CONSUMERS IN SHADOW ECONOMY

    Directory of Open Access Journals (Sweden)

    N. Tyukhtenko

    2016-04-01

    Full Text Available The paper analyzed the level of truthfulness of information as to actual volume revenues of workers of the shadow economy. Revealed results of actual solvency of the local population by goods production, work execution, services rendering. Discovered action of currency fluctuation. Analyzed sales of new cars in Ukraine for 2010-2014. Proposed the method of calculating the correction coefficient with a view to determining the level of objectification purchasing power of consumers in a shadow economy and the potential capacity of the sale market of new cars. Defined the optimal selling price of new vehicles in Kherson. Calculated potential market volume of new vehicles and optimal logistic route of their realization in the Kherson region.

  1. Hybridity in Willa Cather's Death Comes for the Archbishop and Shadows on the Rock

    Directory of Open Access Journals (Sweden)

    Maryam Heydari Fard

    2015-02-01

    Full Text Available Willa Cather wrote Death Comes for the Archbishop and Shadows on the Rock based on the missionary life of Europeans in Quebec and New Mexico. In both novels she depicts a different type of colonizer-colonized relationship. The colonizers arrive with their stereotypical views about the natives to purportedly civilize them. But later, through their interaction with the natives, their superior, patronizing attitude gradually changes, so that, the boundary between the colonizer and the colonized becomes blurred. Contrary to their presuppositions about natives and also the long-established colonial attitude, the missionaries in these two novels treat the natives sympathetically and in some cases equally. Using Homi Bhabha's theory of hybridity, this essay attempts to analyze these two novels in terms of the depiction of cultural relation/interaction.Keywords: Willa Cather, Death Comes for the Archbishop, Shadows on the Rock, Colonialism, Cultural Hybridity

  2. Shadows of the Planck Scale The Changing Face of Compactification Geometry

    CERN Document Server

    Dienes, Keith R; Dienes, Keith R.; Mafi, Arash

    2002-01-01

    By studying the effects of the shape moduli associated with toroidal compactifications, we demonstrate that Planck-sized extra dimensions can cast significant ``shadows'' over low-energy physics. These shadows can greatly distort our perceptions of the compactification geometry associated with large extra dimensions, and place a fundamental limit on our ability to probe the geometry of compactification simply by measuring Kaluza-Klein states. We also discuss the interpretation of compactification radii and hierarchies in the context of geometries with non-trivial shape moduli. One of the main results of this paper is that compactification geometry is effectively renormalized as a function of energy scale, with ``renormalization group equations'' describing the ``flow'' of geometric parameters such as compactification radii and shape angles as functions of energy.

  3. Aggressive shadowing of a low-dimensional model of atmospheric dynamics

    CERN Document Server

    Lieb-Lappen, Ross M

    2011-01-01

    Predictions of the future state of the Earth's atmosphere suffer from the consequences of chaos: numerical weather forecast models quickly diverge from observations as uncertainty in the initial state is amplified by nonlinearity. One measure of the utility of a forecast is its shadowing time, informally given by the period of time for which the forecast is a reasonable description of reality. The present work uses the Lorenz 096 coupled system, a simplified nonlinear model of atmospheric dynamics, to extend a recently developed technique for lengthening the shadowing time of a dynamical system. Ensemble forecasting is used to make forecasts with and without inflation, a method whereby the ensemble is regularly expanded artificially along dimensions whose uncertainty is contracting. The first goal of this work is to compare model forecasts, with and without inflation, to a true trajectory created by integrating a modified version of the same model. The second goal is to establish whether inflation can increas...

  4. An Improved Fuzzy c-Means Clustering Algorithm Based on Shadowed Sets and PSO

    Directory of Open Access Journals (Sweden)

    Jian Zhang

    2014-01-01

    Full Text Available To organize the wide variety of data sets automatically and acquire accurate classification, this paper presents a modified fuzzy c-means algorithm (SP-FCM based on particle swarm optimization (PSO and shadowed sets to perform feature clustering. SP-FCM introduces the global search property of PSO to deal with the problem of premature convergence of conventional fuzzy clustering, utilizes vagueness balance property of shadowed sets to handle overlapping among clusters, and models uncertainty in class boundaries. This new method uses Xie-Beni index as cluster validity and automatically finds the optimal cluster number within a specific range with cluster partitions that provide compact and well-separated clusters. Experiments show that the proposed approach significantly improves the clustering effect.

  5. The movement of shadows: a teaching proposal for the secondary school

    CERN Document Server

    Gangui, Alejandro; Quinteros, Cynthia

    2009-01-01

    A didactic sequence of activities on some topics of Astronomy, related mainly with the length and orientation of shadows cast by a gnomon, the movement of shadows during daytime in different seasons of the year, and finding the true astronomical North, is fully developed. It also includes a discussion of observations from different frames of reference and of some topics in the history of science to enrich a debate among students, as well as the construction of a simplified model for the apparent displacement of the Sun, and of a sundial, and their use as resources to discuss some common misconceptions found in students. Multiple suggestions and clear guides are given for teachers of secondary education to implement theses activities in their classes.

  6. Shadow Bowl 2003: a collaborative exercise in community readiness, agency cooperation, and medical response.

    Science.gov (United States)

    Balch, David; Taylor, Carl; Rosenthal, David; Bausch, Chris; Warner, Dave; Morris, Ray

    2004-01-01

    This paper describes a model for homeland security, community readiness, and medical response that was applied during an operational exercise around Super Bowl XXXVII. In addition, it describes the products provided by private companies involved in the exercise and how they would have contributed to a medical disaster had one occurred. The purpose of Shadow Bowl was to demonstrate community readiness and medical response to a mass casualty event. The goals of the project were to: (1) provide enhanced public safety using an advanced communication network and sensor grid; (2) develop mass casualty surge capabilities through medical reach-back; and (3) build a collaboration model between civilian, military, public, and private partners. The results of the Shadow Bowl Exercise accentuated the value of new telehealth and disaster medicine tools in treating large numbers of patients when infrastructure overload occurs.

  7. Cloud and Cloud Shadow Identification for MERIS and Sentinel-3/OLCI

    Science.gov (United States)

    Pringle, Nicholas; Vanhellemont, Quinten; Ruddick, Kevin

    2015-12-01

    Ocean colour remote sensing has become a well-established method for the monitoring of coastal waters. The MERIS chlorophyll product for turbid waters (algal_2) and the total suspended matter product (tsm) have been used in applications such as algal bloom detection, eutrophication monitoring, and coastal sediment transport. These MERIS L2 products are sometimes contaminated by cloud shadow pixels and the same problems are likely to occur in Sentinel-3. In order to avoid erroneous data passing quality control and being used in applications, an automated method for detecting and removing cloud and cloud shadow pixels is needed. With this in mind, we highlight the problems with MERIS in the past and show some results from applying detection methods to Landsat-8 data with the objective of using these methods for Sentinel-2 and -3 in the future.

  8. [Suprarenal pheochromocytoma appearance as a multiple round shadowing pattern in lungs].

    Science.gov (United States)

    Jeznach, Andrzej; Kozielski, Jerzy

    2010-01-01

    Pheochromocytoma can mimic a number of other diseases, and that's why it is hard to diagnose. The classic triad of symptoms are episodic headache, excessive sweating and palpitation. Hereby I present a case without any symptoms mentioned above. A 58-year-old patient with controlled hypertension without any previous complaints connected with respiratory tract, was admitted to hospital because of round shadows found in chest X-ray. The attempts to find initial focus as a basis of neoplasma failed. Postmortal histologic examination of the adrenal glands revealed pheochromocytoma with multiple focuses in lungs and mediastinal lymph nodes. Diagnosis pheochromocytoma was as surprising for the physicians as for pathologists despite the presence of a small tumor of the left adrenal gland found previously in CT scan of the abdomen. In case of presence of "round shadows" in lungs connected with changes in adrenal glands one ought to think about pheochromosytoma.

  9. THE SHADOW BANKING SYSTEM AND ITS ROLE IN TRIGGERING THE GLOBAL CRISIS

    Directory of Open Access Journals (Sweden)

    Carmen BOGHEAN

    2015-04-01

    Full Text Available Financial innovation, the deficiencies of corporate governance, moral hazard, easy money policies, government inefficiency, and mainly the activity of the shadow banking system have all played a critical role in setting off the global financial crisis. Due to the imbalances it has triggered, the shadow banking system has been at the core of the most widespread and profound world crisis of all time, as the attempt to use financial capital as efficiently as possible by resorting to “innovative” products has significantly contributed to the advent of the financial crisis. The present crisis has already proved that the banking and financial activity can have a deeply disturbing impact on our economy, but the flexibility of lending mechanisms and the various reactions of the players on the market that are otherwise inherent in a dynamic economic system, cannot exist in the absence of banking mechanisms.

  10. On the performance of transmit antenna selection based on shadowing side information

    KAUST Repository

    Yilmaz, Ahmet Oǧuz

    2013-01-01

    In this paper, a transmit antenna selection scheme, which is based on shadowing side information, is investigated. In this scheme, the selected single transmit antenna provides the highest shadowing coefficient between a transmitter and a receiver. By the proposed technique, the frequency of the usage of the feedback channel from the receiver to the transmitter and channel estimation complexity at the receiver can be reduced. We study the performance of our proposed technique, and in the analysis, we consider an independent but not identically distributed generalized-K composite fading model. More specifically, exact and closed-form expressions for the outage probability, the moment-generating function, the moments of signal-to-noise ratio, and the average symbol error probability (SEP) are derived. In addition, asymptotic outage probability and SP expressions are also presented to investigate the diversity order and the array gain. Finally, our theoretical performance results are validated by Monte Carlo simulations. © 2012 IEEE.

  11. Modeling and reconfiguration of solar photovoltaic arrays under non-uniform shadow conditions

    Science.gov (United States)

    Nguyen, Dung Duc

    Mass production and use of electricity generated from solar energy has become very common recently because of the environmental threats arising from the production of electricity from fossil fuels and nuclear power. The obvious benefits of solar energy are clean energy production and infinite supply of daylight. The main disadvantage is the high cost. In these photovoltaic systems, semiconductor materials convert the solar light into electrical energy. Current versus voltage characteristics of the solar cells are nonlinear, thus leading to technical control challenges. In the first order approximation, output power of a solar array is proportional to the irradiance of sunlight. However, in many applications, such as solar power plants, building integrated photovoltaic or solar tents, the solar photovoltaic arrays might be illuminated non-uniformly. The cause of non-uniform illumination may be the shadow of clouds, the trees, booms, neighbor's houses, or the shadow of one solar array on the other, etc. This further leads to nonlinearities in characteristics. Because of the nature of the electrical characteristics of solar cells, the maximum power losses are not proportional to the shadow, but magnify nonlinearly [1]. Further, shadows of solar PV array can cause other undesired effects: (1) The power actually generated from the solar PV array is much less than designed. At some systems, the annual losses because of the shadow effects can be reached 10%. Thus, the probability for "loss of load" increases [2]. (2) The local hot spot in the shaded part of the solar PV array can damage the solar cells. The shaded solar cells may be work on the negative voltage region and become a resistive load and absorb power. Bypass diodes are sometimes connected parallel to solar cells to protect them from damage. However, in most cases, just one diode is connected in parallel to group of solar cells [3], and this hidden the potential power output of the array. This proposed research

  12. A New SAR Image Segmentation Algorithm for the Detection of Target and Shadow Regions

    Science.gov (United States)

    Huang, Shiqi; Huang, Wenzhun; Zhang, Ting

    2016-12-01

    The most distinctive characteristic of synthetic aperture radar (SAR) is that it can acquire data under all weather conditions and at all times. However, its coherent imaging mechanism introduces a great deal of speckle noise into SAR images, which makes the segmentation of target and shadow regions in SAR images very difficult. This paper proposes a new SAR image segmentation method based on wavelet decomposition and a constant false alarm rate (WD-CFAR). The WD-CFAR algorithm not only is insensitive to the speckle noise in SAR images but also can segment target and shadow regions simultaneously, and it is also able to effectively segment SAR images with a low signal-to-clutter ratio (SCR). Experiments were performed to assess the performance of the new algorithm on various SAR images. The experimental results show that the proposed method is effective and feasible and possesses good characteristics for general application.

  13. A Method of Survey on Object-Oriented Shadow Detection & Removal for High Resolution Urban Aerial Colour Images

    Directory of Open Access Journals (Sweden)

    A.Amareswar Kumar,

    2015-12-01

    Full Text Available High-resolution remote sensing images offer great possibilities for urban mapping. Unfortunately, shadows cast by buildings during this some problems occurred .This paper mainly focus to get the high resolution colour remote sensing image, and also undertaken to remove the shaded region in the both urban and rural areas. The region growing thresholding algorithm is used to detect the shadow and extract the features from shadow region. Then determine whether those neighbouring pixels are added to the seed points or not. In the region growing threshold algorithm, Pixels are placed in the region based on their properties or the properties of nearby pixel values. Then the pixels containing similar properties are grouped together and distributed throughout the image. IOOPL matching is used for removing shadow from image. This method proves it can remove 80% shaded region from image efficiently.

  14. Electroencephalogram evidence for the activation of human mirror neuron system during the observation of intransitive shadow and line drawing actions

    Institute of Scientific and Technical Information of China (English)

    Huaping Zhu; Yaoru Sun; Fang Wang

    2013-01-01

    Previous studies have demonstrated that hand shadows may activate the motor cortex associated with the mirror neuron system in human brain. However, there is no evidence of activity of the human mirror neuron system during the observation of intransitive movements by shadows and line drawings of hands. This study examined the suppression of electroencephalography mu waves hand actions, hand shadow actions and actions made by line drawings of hands. The results showed significant desynchronization of the mu rhythm ("mu suppression") across the sensorimotor cortex (recorded at C3, Cz and C4), the frontal cortex (recorded at F3, Fz and F4) and the central and right posterior parietal cortex (recorded at Pz and P4) under all three conditions. Our experimental findings suggest that the observation of "impoverished hand actions", such as intransitive movements of shadows and line drawings of hands, is able to activate widespread cortical areas related to the putative human mirror neuron system.

  15. Memory Without Parties or Parties Without Memory?

    Directory of Open Access Journals (Sweden)

    Juan Mario Solís Delgadillo

    2011-01-01

    Full Text Available This paper explores the role of political parties in Argentina, Chile and Guatemala in relation to the implementation of public policies of memory after the return to democracy in each of these countries. To do this, we discuss the concept of memory and the problems of memorial obsession. We consider the uses and abuses of memory that human rights organizations manifest on the subject, and examine the work of the parties about the level of adaptation that allows claims of human rights movement to become matters of public policy.

  16. Exposure data for cosmetic products: facial cleanser, hair conditioner, and eye shadow.

    Science.gov (United States)

    Loretz, L J; Api, A M; Babcock, L; Barraj, L M; Burdick, J; Cater, K C; Jarrett, G; Mann, S; Pan, Y H L; Re, T A; Renskers, K J; Scrafford, C G

    2008-05-01

    Reliable exposure information for cosmetic and other personal care products and ingredients is needed in order to conduct safety assessments. Essential information includes both the amount of product applied, and the frequency of use. To obtain current data, a study to assess consumer use practices was undertaken. Three widely used types of cosmetic products - facial cleanser, hair conditioner, and eye shadow - were included in the study. Three hundred and sixty women, ages 18-69 years, who regularly use the products of interest, were recruited nationwide within the US. Subjects were provided with a new container of the brand of product they normally use and kept diaries and recorded detailed daily usage information over a two week period. Products were weighed at the start and completion of the study in order to determine the total amount of product used. Statistical analyses of the data were conducted to derive summary distributions of use patterns. The mean and median usage per application, respectively, for the three product types were: facial cleanser, 2.57 g and 2.11 g; hair conditioner, 13.13 g and 10.21 g; and eye shadow, 0.03 g and 0.009 g. The mean and median usage per day for the three product types was: facial cleanser, 4.06 g and 3.25 g; hair conditioner, 13.77 g and 10.62 g; and eye shadow, 0.04 g and 0.010 g. The mean number of applications per day for facial cleanser, hair conditioner, and eye shadow was 1.6, 1.1, and 1.2, respectively. This study provides an estimate of current exposure information for commonly used products which will be useful for risk assessment purposes.

  17. Diagnosing as the shadow side of the idea of the learning subject

    DEFF Research Database (Denmark)

    Hamre, Bjørn

    This presentation focuses on a discussion of these issues in a Danish school context in which the increasing use of diagnosis is analyzed as resulting from the ideas of normality that are associated with being a learner in school. I argue that diagnosis in schools can be seen as the shadow side o...... of looking at being a pupil in school, each of which represents conceptions of normality and deviance. The presentation’s methodological point of departure draws on a poststructuralistic framework....

  18. Using stress shadows to invert for changes in local stress field

    Science.gov (United States)

    Latimer, C. D.; Tiampo, K. F.; Rundle, J.

    2009-12-01

    When a large earthquake occurs, stresses in the crust are redistributed creating regions that experience an increase in stress while others experience a stress decrease which are called stress shadows. In many studies, these stress shadows are said to contain less seismic activity than the average background rate, and so correlations are made between lack of seismicity or a decrease in seismicity rate and the stress shadow locations and magnitudes (the amount of decrease of stress). In this study the opposite procedure is applied: We use seismicity rate changes to determine information about the stress changes due to a large magnitude earthquake, as well as its effect on the stress field itself. We use the Pattern Informatics method to examine the changes in seismicity rate, as it is an objective measure of the rate changes with respect to the regional background rate. The results from this analysis are then used to invert for, with a genetic algorithm, parameters that define the stress field such as the principal stress orientations, the coefficient of friction, and the calculation depth. The modelled stress data is calculated using Coulomb stress change theory and the Coulomb 3 program, and it is trying to produce the same size and location of stress shadows as seen in the seismicity rate change data. Four different Californian earthquakes were chosen in order to determine their effect on the local stress field: (1) 1987 Superstition Hills (2) 1989 Loma Prieta (3) 1992 Landers and (4) 1994 Northridge. In order to find out the effect that each of the parameters have on the modelled results, we performed a Monte Carlo simulation to find the errors associated with each, and a sensitivity analysis to determine the magnitude of change that each one produces. We hope with this new information of the changes incurred due to a large magnitude earthquake occurrence, that modelling of earthquakes can be advanced, and our understanding of their mechanics enhanced.

  19. Simulation of the cosmic ray moon shadow at the MINOS Far Detector

    Energy Technology Data Exchange (ETDEWEB)

    Medeiros, Michelle Mesquita de; Gomes, Ricardo Avelino [Universidade Federal de Goias (UFG), GO (Brazil). Inst. de Fisica

    2011-07-01

    Full text: A fraction of the cosmic ray primaries are blocked by the Moon causing a shadow that can be observed in underground detectors by the means of muon detection. Atmospheric muons are originated in extensive air showers when the cosmic ray primary particle interacts with molecules at the top of the atmosphere. The Moon shadowing effect can be used to study the behaviour of the geomagnetic, solar and interplanetary magnetic fields, to measure the antiproton-proton ratio and to determine the angular resolution and alignment of the detectors to confirm its accuracy and precision. In this report we present the results of a Moon shadow simulation using CORSIKA (a Monte Carlo code which simulates extensive air showers) with the QGSJET hadronic model for high energy interactions. We used the MINOS Far Detector technical features for the means of energy and angular acceptance. The Far Detector is a large tracking calorimeter made of plastic scintillator and steel located in the Soudan Underground Mine State Park, MN, at a depth of 713 m (2070 meters of water equivalent - mwe). Although the primary purpose of the MINOS experiment is the detection of neutrino disappearance using a NuMI beam line, it is an efficient cosmic-ray muon detector since it is at a large depth and has wide acceptance combined with a flat overburden of the Soudan site. We describe the event generation process for the simulation, the event reconstruction and the criteria to select the events that the Far Detector can observe. We compare the simulation of the Moon shadow caused by different cosmic ray primaries (proton, helium and iron nucleus) using two distinct methods (Moon as a deficit and as a source). In addition we simulated the motion of the Moon using a large sample of cosmic ray primaries to compare with the MINOS Far Detector results. (author)

  20. Segmentation of the spinous process and its acoustic shadow in vertebral ultrasound images.

    Science.gov (United States)

    Berton, Florian; Cheriet, Farida; Miron, Marie-Claude; Laporte, Catherine

    2016-05-01

    Spinal ultrasound imaging is emerging as a low-cost, radiation-free alternative to conventional X-ray imaging for the clinical follow-up of patients with scoliosis. Currently, deformity measurement relies almost entirely on manual identification of key vertebral landmarks. However, the interpretation of vertebral ultrasound images is challenging, primarily because acoustic waves are entirely reflected by bone. To alleviate this problem, we propose an algorithm to segment these images into three regions: the spinous process, its acoustic shadow and other tissues. This method consists, first, in the extraction of several image features and the selection of the most relevant ones for the discrimination of the three regions. Then, using this set of features and linear discriminant analysis, each pixel of the image is classified as belonging to one of the three regions. Finally, the image is segmented by regularizing the pixel-wise classification results to account for some geometrical properties of vertebrae. The feature set was first validated by analyzing the classification results across a learning database. The database contained 107 vertebral ultrasound images acquired with convex and linear probes. Classification rates of 84%, 92% and 91% were achieved for the spinous process, the acoustic shadow and other tissues, respectively. Dice similarity coefficients of 0.72 and 0.88 were obtained respectively for the spinous process and acoustic shadow, confirming that the proposed method accurately segments the spinous process and its acoustic shadow in vertebral ultrasound images. Furthermore, the centroid of the automatically segmented spinous process was located at an average distance of 0.38 mm from that of the manually labeled spinous process, which is on the order of image resolution. This suggests that the proposed method is a promising tool for the measurement of the Spinous Process Angle and, more generally, for assisting ultrasound-based assessment of scoliosis

  1. Getting to Negotiations in Syria: The Shadow of the Future and the Syrian Civil War

    Science.gov (United States)

    2014-01-01

    they were held simultaneously with, or after, a major donor’s conference to gather pledges for postconflict reconstruction and a meeting of the Secu...guarantee the peace and provide resources for reconstruction , they Getting to Negotiations in Syria The Shadow of the Future and the Syrian Civil War Paul D...promising a peacekeeping and reconstruction force that will start after they have agreed to peace. Background The civil war in Syria war grew out of

  2. Shadowing corrections to the derivative of the reduced cross-section at small

    Indian Academy of Sciences (India)

    B Rezaei; G R Boroun

    2014-06-01

    We analyse the derivative of the reduced cross-section $\\dfrac{\\partial ^s_r}{\\partial ln y}|_x$, using the nonlinear Dokshitzer–Gribov–Lipatov–Altarelli–Parisi (NLDGLAP) evolution equation at small . The small behaviour of the structure functions are obtained by solving the Gribov, Levin, Ryskin, Mueller and Qiu (GLR-MQ) evolution equation with the nonlinear shadowing term incorporated. We show that the strong rise corresponding to the linear QCD evolution equations, can be tamed by screening effects.

  3. Observation of a shadow of the Moon in the underground muon flux in the Soudan 2 detector

    Science.gov (United States)

    Cobb, J. H.; Marshak, M. L.; Allison, W. W.; Alner, G. J.; Ayres, D. S.; Barrett, W. L.; Bode, C.; Border, P. M.; Brooks, C. B.; Cotton, R. J.; Courant, H.; Demuth, D. M.; Fields, T. H.; Gallagher, H. R.; Goodman, M. C.; Gran, R.; Joffe-Minor, T.; Kafka, T.; Kasahara, S. M.; Leeson, W.; Litchfield, P. J.; Longley, N. P.; Mann, W. A.; Milburn, R. H.; Miller, W. H.; Moon, C.; Mualem, L.; Napier, A.; Oliver, W. P.; Pearce, G. F.; Peterson, E. A.; Petyt, D. A.; Price, L. E.; Ruddick, K.; Sanchez, M.; Sankey, P.; Schneps, J.; Schub, M. H.; Seidlein, R.; Stassinakis, A.; Thron, J. L.; Vassiliev, V.; Villaume, G.; Wakely, S. P.; West, N.; Wall, D.

    2000-05-01

    A shadow of the Moon, with a statistical significance of 5σ, has been observed in the underground muon flux at a depth of 2090 mwe using the Soudan 2 detector. The angular resolution of the detector is well described by a Gaussian with a sigma <=0.3°. The position of the shadow confirms that the alignment of the detector is known to better than 0.15° and has remained stable during ten years of data taking.

  4. Moments Of Microdiversity EGC Receivers And Macrodiversity SC Receiver Output Signal Over Gamma Shadowed Nakagami-m Multipath Fading Channel

    Science.gov (United States)

    Djordjević, Nebojša; Jaksić, Branimir S.; Matović, Ana; Matović, Marija; Smilić, Marko

    2015-11-01

    A system with macrodiversity selection combining (SC) receiver and for microdiversity equal gain combining (EGC) receivers is considered. Received signal is subjected, simultaneously to multipath fading and shadowing, resulting in signal envelope and signal power variation. Closed form expressions for moments of macrodiversity SC receiver output signal envelope are calculated. Numerical expressions are plotted to present the influences of Gamma shadowing severity and Nakagami-m severity on moments of proposed system output signal.

  5. Segmentation of Shadowed Buildings in Dense Urban Areas from Aerial Photographs

    Directory of Open Access Journals (Sweden)

    Junichi Susaki

    2012-03-01

    Full Text Available Segmentation of buildings in urban areas, especially dense urban areas, by using remotely sensed images is highly desirable. However, segmentation results obtained by using existing algorithms are unsatisfactory because of the unclear boundaries between buildings and the shadows cast by neighboring buildings. In this paper, an algorithm is proposed that successfully segments buildings from aerial photographs, including shadowed buildings in dense urban areas. To handle roofs having rough textures, digital numbers (DNs are quantized into several quantum values. Quantization using several interval widths is applied during segmentation, and for each quantization, areas with homogeneous values are labeled in an image. Edges determined from the homogeneous areas obtained at each quantization are then merged, and frequently observed edges are extracted. By using a “rectangular index”, regions whose shapes are close to being rectangular are thus selected as buildings. Experimental results show that the proposed algorithm generates more practical segmentation results than an existing algorithm does. Therefore, the main factors in successful segmentation of shadowed roofs are (1 combination of different quantization results, (2 selection of buildings according to the rectangular index, and (3 edge completion by the inclusion of non-edge pixels that have a high probability of being edges. By utilizing these factors, the proposed algorithm optimizes the spatial filtering scale with respect to the size of building roofs in a locality. The proposed algorithm is considered to be useful for conducting building segmentation for various purposes.

  6. Diffuse sky radiation influences the relationship between canopy PRI and shadow fraction

    Science.gov (United States)

    Mõttus, Matti; Takala, Tuure L. H.; Stenberg, Pauline; Knyazikhin, Yuri; Yang, Bin; Nilson, Tiit

    2015-07-01

    The Photochemical Reflectance Index (PRI) of green leaves is an indicator of photosynthetic downregulation: when the photosynthetic apparatus is close to the saturation limit, PRI becomes dependent on light conditions. Therefore, by measuring the PRI of leaves under different local irradiance conditions, it should be possible to determine the saturation level of the leaves and obtain information on the light use efficiency (LUE) of a vegetation canopy. The dependence of PRI on the ratio of sunlit to shaded foliage (quantified by the canopy shadow fraction) in the field of view of an instrument has been used to remotely measure canopy LUE on clear days. However, besides photosynthetic downregulation, the dependence of canopy PRI on shadow fraction is affected by the blue sky radiation caused by scattering in the atmosphere. To quantify this effect on remotely sensed PRI, we present the underlying definitions relating leaf and canopy PRI and perform the required calculations for typical midsummer conditions in Central Finland. We demonstrate that the effect of blue sky radiation on the variation of PRI with canopy shadow fraction is similar in shape and magnitude to that of LUE variations reported in literature.

  7. A Shadow Curriculum: Incorporating Students' Interests into the Formal Biology Curriculum

    Science.gov (United States)

    Hagay, Galit; Baram-Tsabari, Ayelet

    2011-11-01

    Students have been largely ignored in discussions about how best to teach science, and many students feel the curriculum is detached from their lives and interests. This article presents a strategy for incorporating students' interests into the formal Biology curriculum, by drawing on the political meaning of "shadow government" as alternative policies developed by parties not in office. A "shadow curriculum" thus reflects the interests and information needs of those who have no voice in deciding what the formal curriculum should include, although they are the ones who are most influenced by it. High school students' interests in three Biology topics were identified ( n = 343) and retested on another student sample ( n = 375), based on their solicited questions as indicators for interests. The results of this exploratory case study showed that half of the questions asked by students in the areas of genetics, the cardiovascular system and the reproductive system are not addressed by the national curriculum. Students' questions were then expressed in the curricular language of principles, phenomena and concepts in order to create a shadow curriculum. A procedure that could be used by other researchers and practitioners to guide the development of a curriculum that is more aligned with student interests is suggested.

  8. K Coverage Probability of 5G Wireless Cognitive Radio Network under Shadow Fading Effects

    Directory of Open Access Journals (Sweden)

    Ankur S. Kang

    2016-09-01

    Full Text Available Land mobile communication is burdened with typical propagation constraints due to the channel characteristics in radio systems.Also,the propagation characteristics vary form place to place and also as the mobile unit moves,from time to time.Hence,the tramsmission path between transmitter and receiver varies from simple direct LOS to the one which is severely obstructed by buildings,foliage and terrain.Multipath propagation and shadow fading effects affect the signal strength of an arbitrary Transmitter-Receiver due to the rapid fluctuations in the phase and amplitude of signal which also determines the average power over an area of tens or hundreds of meters.Shadowing introduces additional fluctuations,so the received local mean power varies around the area –mean.The present section deals with the performance analysis of fifth generation wireless cognitive radio network on the basis of signal and interference level based k coverage probability under the shadow fading effects.

  9. Measuring the Kerr spin parameter of regular black holes from their shadow

    CERN Document Server

    Li, Zilong

    2014-01-01

    In a previous paper, one of us has showed that at least some non-Kerr metrics are extremely difficult to test and current techniques, even in presence of excellent data not available today, cannot distinguish a Kerr black hole from a Bardeen one, despite the substantial difference of the two backgrounds. In this paper, we investigate if the detection of the "shadow" of nearby super-massive black hole candidates by near future mm/sub-mm very long baseline interferometry experiments can do the job. More specifically, we consider the measurement of the Kerr spin parameter of the Bardeen and Hayward regular black holes from their shadow, and we then compare the result with the estimate inferred from the K$\\alpha$ iron line and from the frequency of the innermost stable circular orbit. The shadow approach provides different values for non-rotating black holes, but quite similar results for near extremal objects. The present work confirms that it is definitively challenging to test this kind of metrics, even with f...

  10. Training Classifiers with Shadow Features for Sensor-Based Human Activity Recognition

    Science.gov (United States)

    Fong, Simon; Song, Wei; Cho, Kyungeun; Wong, Raymond; Wong, Kelvin K. L.

    2017-01-01

    In this paper, a novel training/testing process for building/using a classification model based on human activity recognition (HAR) is proposed. Traditionally, HAR has been accomplished by a classifier that learns the activities of a person by training with skeletal data obtained from a motion sensor, such as Microsoft Kinect. These skeletal data are the spatial coordinates (x, y, z) of different parts of the human body. The numeric information forms time series, temporal records of movement sequences that can be used for training a classifier. In addition to the spatial features that describe current positions in the skeletal data, new features called ‘shadow features’ are used to improve the supervised learning efficacy of the classifier. Shadow features are inferred from the dynamics of body movements, and thereby modelling the underlying momentum of the performed activities. They provide extra dimensions of information for characterising activities in the classification process, and thereby significantly improve the classification accuracy. Two cases of HAR are tested using a classification model trained with shadow features: one is by using wearable sensor and the other is by a Kinect-based remote sensor. Our experiments can demonstrate the advantages of the new method, which will have an impact on human activity detection research. PMID:28264470

  11. Characterizing magnetopause shadowing effects in the outer electron radiation belt during geomagnetic storms

    Science.gov (United States)

    Herrera, D.; Maget, V. F.; Sicard-Piet, A.

    2016-10-01

    Relativistic electrons dynamics is still challenging to predict during the main phase of a storm. In particular, three dimensions radiation belt models, for which temporal resolution is limited, fail in predicting their behavior, especially when dropouts occur. In this paper we present a new model of magnetopause shadowing losses to be incorporated into the ONERA Salammbô code in order to improve the model accuracy. We show in this paper that above a few hundred keVs, magnetopause shadowing is the first contribution to losses in the outer electron belt during dropout events. Global variations of Earth-magnetopause distance and relativistic electron flux have been analyzed to establish the correlation between the magnetopause shadowing and dropouts on the outer electron radiation belt during geomagnetic storms. To that purpose, a Superposed Epoch Analysis has been done using NOAA Polar-orbiting Operational Environmental Satellite 15 measurements. First, a list of 67 Stream Interfaces has been used to validate the method, and then the Superposed Epoch Analysis has been run over more than one solar cycle. Our results show that the model of magnetopause location we have developed fits well with a Superposed Epoch Analysis performed and that we are able to define a criteria based on it that detect intense dropouts. Finally, we have included this model in the Salammbô code, and we present here the improvements obtained as well as the validation made.

  12. Diversification of nanostructure morphology by modifying angle-resolved heterogeneous shadow mask.

    Science.gov (United States)

    Wang, Chaoguang; Wu, Xuezhong; Dong, Peitao; Wang, Junfeng; Di, Di; Chen, Jian; Wang, Haoxu

    2013-12-01

    This article presents a facile and generally applicable methodology for the morphology diversification of two-dimensional (2D) nanostructure arrays by modifying angle-resolved heterogeneous shadow mask (AR-HSM). Colloid spheres are used to prepare scalable well-organized monolayer film by self-assembly method and then etched in oxygen plasma to reduce size. Subsequently, the heterogeneous layer is generated by tilted metal deposition technique, then utilized as shadow mask in the substrate etching process, and finally removed by wet etching technique. As a result, the controllable fabrication of a series of complex morphologies, ranging from the crescent structure to the hoof-like structure and the stripes with apexes, is realized. The morphology of the nanostructure array is depend on the profile of the heterogeneous shadow mask (HSM) which is correlated to the incidence angle of the metal vapor. Therefore, a theoretical model is built for the prediction and design of the nanostructure morphology. This AR-HSM aided approach provides a novel and accessible route for the diversification of nanostructure morphology; and can be readily extended to other functional substrates which may be applied in photovoltaic devices or bio-chemical sensors.

  13. The shadows cast by buildings and towers in cities and by montains in the countryside

    Directory of Open Access Journals (Sweden)

    Moreira João Luiz Kohl

    2003-01-01

    Full Text Available ABSTRACT Often astronomers of the Observatório Nacional are asked about how the shadow cast from a building or a tower to be built will impact crowded areas; in which way they would interfere with the wellfare by depriving population from sunlight. The same problem arises when agronomers plan areas for cultures when topographical accidents may cast shadows in a geographic region. My colleages usually answer these questions by delivering spherical trigonometry formulae and the sun equations of movement, and therefore they transfer the responsability of the conclusions back to the engineers and agronomers. What we didn?t realize is the possible and even probable difficulties that these professionals could be facing, since fundamental astronomy and astronomical object positioning knowledge is needed to figure out how the sun moves in the celestial sphere. Shadow projection and its mapping on a ground plan also requires specific knowledge. This paper intends to introduce solutions that will offer professionals, teachers and students conditions of better understanding this problem and, possibly, at least in some cases, bypass the need for quering astronomers.

  14. The Contribution of the Human Body in Young Children's Explanations About Shadow Formation

    Science.gov (United States)

    Herakleioti, Evagelia; Pantidos, Panagiotis

    2016-02-01

    This paper begins with the view that the generation of meaning is a multimodal process. Props, drawings, graphs, gestures, as well as speech and written text are all mediators through which students construct new knowledge. Each semiotic context makes a unique contribution to the conceptualization of scientific entities. The human body, in particular, can function as a factor in both representation and explanation, serving as a link between verbal discourse and setting. Considering this perspective, a body-based activity was designed for kindergarten children, involving the concept of a shadow. The 3-D arrangement of the light from the light source, the human body (the obstacle), and the resulting shadow plays a central role. Using their own bodies as obstacles to the light, the children were able to explore the direction of the light and to change the relative positions of the light source and the obstacle. They formed hypotheses and were able to test them by moving on the stage. This body-centered activity explicitly incorporates the rectilinear movement of light into the process of shadow formation, while also providing learning through direct experience. Positive effects on learning were achieved for the group of children who participated in the activity, while the video analysis showed that many of the children were able to use their bodies to transfer to a different setting the embodied knowledge they acquired. This, according to researchers in the field of science education, is a powerful indication of conceptual change.

  15. New method for shadow calculations: Application to parametrized axisymmetric black holes

    Science.gov (United States)

    Younsi, Ziri; Zhidenko, Alexander; Rezzolla, Luciano; Konoplya, Roman; Mizuno, Yosuke

    2016-10-01

    Collaborative international efforts under the name of the Event Horizon Telescope project, using sub-mm very long baseline interferometry, are soon expected to provide the first images of the shadow cast by the candidate supermassive black hole in our Galactic center, Sagittarius A*. Observations of this shadow would provide direct evidence of the existence of astrophysical black holes. Although it is expected that astrophysical black holes are described by the axisymmetric Kerr solution, there also exist many other black hole solutions, both in general relativity and in other theories of gravity, which cannot presently be ruled out. To this end, we present calculations of black hole shadow images from various metric theories of gravity as described by our recent work on a general parametrization of axisymmetric black holes [R. Konoplya, L. Rezzolla, and A. Zhidenko, Phys. Rev. D 93, 064015 (2016).]. An algorithm to perform general ray-tracing calculations for any metric theory of gravity is first outlined and then employed to demonstrate that even for extremal metric deformation parameters of various black hole spacetimes, this parametrization is both robust and rapidly convergent to the correct solution.

  16. Training Classifiers with Shadow Features for Sensor-Based Human Activity Recognition

    Directory of Open Access Journals (Sweden)

    Simon Fong

    2017-02-01

    Full Text Available In this paper, a novel training/testing process for building/using a classification model based on human activity recognition (HAR is proposed. Traditionally, HAR has been accomplished by a classifier that learns the activities of a person by training with skeletal data obtained from a motion sensor, such as Microsoft Kinect. These skeletal data are the spatial coordinates (x, y, z of different parts of the human body. The numeric information forms time series, temporal records of movement sequences that can be used for training a classifier. In addition to the spatial features that describe current positions in the skeletal data, new features called ‘shadow features’ are used to improve the supervised learning efficacy of the classifier. Shadow features are inferred from the dynamics of body movements, and thereby modelling the underlying momentum of the performed activities. They provide extra dimensions of information for characterising activities in the classification process, and thereby significantly improve the classification accuracy. Two cases of HAR are tested using a classification model trained with shadow features: one is by using wearable sensor and the other is by a Kinect-based remote sensor. Our experiments can demonstrate the advantages of the new method, which will have an impact on human activity detection research.

  17. Chasing Shadows: Rotation of the Azimuthal Asymmetry in the TW Hya Disk

    Science.gov (United States)

    Debes, John H.; Poteet, Charles A.; Jang-Condell, Hannah; Gaspar, Andras; Hines, Dean; Kastner, Joel H.; Pueyo, Laurent; Rapson, Valerie; Roberge, Aki; Schneider, Glenn; hide

    2017-01-01

    We have obtained new images of the protoplanetary disk orbiting TW Hya in visible, total intensity light with the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope (HST), using the newly commissioned BAR5 occulter. These HSTSTIS observations achieved an inner working angle of approximately 0 "2, or11.7 au, probing the system at angular radii coincident with recent images of the disk obtained by ALMA and in polarized intensity near-infrared light. By comparing our new STIS images to those taken with STIS in 2000 and with NICMOS in 1998, 2004, and 2005, we demonstrate that TW Hyas azimuthal surface brightness asymmetry moves coherently in position angle. Between 50 au and 141 au we measure a constant angular velocity in the azimuthal brightness asymmetry of 22.deg7 yr(exp -1) in a counterclockwise direction, equivalent to a period of 15.9yrassuming circular motion. Both the (short) inferred period and lack of radial dependence of the moving shadow pattern are inconsistent with Keplerian rotation at these disk radii. We hypothesize that the asymmetry arises from the fact that the disk interior to 1 au is inclined and precessing owing to a planetary companion, thus partially shadowing the outer disk. Further monitoring of this and other shadows on protoplanetary disks potentially opens anew avenue for indirectly observing the sites of planet formation.

  18. The Academic Success of East Asian American Youth: The Role of Shadow Education

    Science.gov (United States)

    Byun, Soo-yong; Park, Hyunjoon

    2013-01-01

    Using data from the Education Longitudinal Study, this study assessed the relevance of shadow education to the high academic performance of East Asian American students by examining how East Asian American students differed from other racial/ethnic students in the prevalence, purpose, and effects of using the two forms – commercial test preparation service and private one-to-one tutoring – of SAT coaching, defined as the American style of shadow education. East Asian American students were most likely to take a commercial SAT test preparation course for the enrichment purpose, and benefited most from taking this particular form of SAT coaching. However, this was not the case for private SAT one-to-one tutoring. While black students were most likely to utilize private tutoring for the remedial purpose, the impact of private tutoring was trivial for all racial/ethnic groups including East Asian American students. The authors discussed broader implications of the findings on racial/ethnic inequalities in educational achievement beyond the relevance of shadow education for the academic success of East Asian American students. PMID:24163483

  19. Indoor and outdoor people detection and shadow suppression by exploiting HSV color information

    Institute of Scientific and Technical Information of China (English)

    Baisheng CHEN

    2008-01-01

    An adaptive background model based on max-imum statistical probability and a shadow suppression scheme for indoor and outdoor people detection by exploiting hue saturation value (HSV) color information is proposed. To obtain the initial background scene, the frequency of R, G, and B component values for each pixel at the same position in the learning sequence are respec-tively calculated; the R, G, and B component values with the biggest ratios are incorporated to model the initial background. The background maintenance, or the so-called background re-initiation, is also proposed to adapt to scene changes such as illumination changes and scene geometry changes. Moving cast shadows generally exhibit a challenge for accurate moving target detection. Based on the observation that a shadow cast on a background region lowers its brightness but does not change its chro-maticity significantly, we address this problem in the ar-ticle by exploiting HSV color information. In addition, quantitative metrics is introduced to evaluate the algo-rithm on a benchmark suite of indoor and outdoor video sequences. The experimental results are given to show the performance of the algorithm.

  20. Sensing Coverage Prediction for Wireless Sensor Networks in Shadowed and Multipath Environment

    Science.gov (United States)

    Kumar, Sushil; Lobiyal, D. K.

    2013-01-01

    Sensing coverage problem in wireless sensor networks is a measure of quality of service (QoS). Coverage refers to how well a sensing field is monitored or tracked by the sensors. Aim of the paper is to have a priori estimate for number of sensors to be deployed in a harsh environment to achieve desired coverage. We have proposed a new sensing channel model that considers combined impact of shadowing fading and multipath effects. A mathematical model for calculating coverage probability in the presence of multipath fading combined with shadowing is derived based on received signal strength (RSS). Further, the coverage probability derivations obtained using Rayleigh fading and lognormal shadowing fading are validated by node deployment using Poisson distribution. A comparative study between our proposed sensing channel model and different existing sensing models for the network coverage has also been presented. Our proposed sensing model is more suitable for realistic environment since it determines the optimum number of sensors required for desirable coverage in fading conditions. PMID:24250271