The Role of Depth Stratification in the Solution of the Aperture Problem

Perception ◽  
1993 ◽  
Vol 22 (2) ◽  
pp. 215-228 ◽  
Author(s):  
Paola Bressan ◽  
Giorgio Ganis ◽  
Giorgio Vallortigara

When a plaid pattern composed of a stationary vertical grating and a horizontally drifting diagonal grating is shown behind a circular aperture, the pattern appears to move coherently in a vertical direction. When the bars of the stationary grating are narrower than those of the moving grating, only the latter is seen to move, in a direction orthogonal to its orientation (ie diagonal); but when the bars of the stationary grating are wider than those of the moving grating, vertical motion of the whole plaid predominates. It is argued that, in the absence of occlusion information, the motion of a plaid within an aperture depends on the unambiguous displacement of inner line terminators at the crossings of the two gratings. Relative motion and differences in bar width between the two gratings provide information about which set of bars is in front of the other. When these sources of information are consistent with each other, separation of the two gratings in depth occurs: inner line terminators no longer perceptually exist and the direction of motion becomes determined only by terminators at the edges, which causes a shift from vertical to orthogonal motion. Differences in luminance also provide (asymmetrical) information about depth relationships: when darker bars occlude lighter bars, the probability of orthogonal motion increases as a function of the difference in luminance, whereas when lighter bars are over darker bars, vertical motion prevails.

2008 ◽  
Vol 61 (11) ◽  
pp. 1601-1619 ◽  
Author(s):  
Anne Cutler

Speech processing by human listeners derives meaning from acoustic input via intermediate steps involving abstract representations of what has been heard. Recent results from several lines of research are here brought together to shed light on the nature and role of these representations. In spoken-word recognition, representations of phonological form and of conceptual content are dissociable. This follows from the independence of patterns of priming for a word's form and its meaning. The nature of the phonological-form representations is determined not only by acoustic-phonetic input but also by other sources of information, including metalinguistic knowledge. This follows from evidence that listeners can store two forms as different without showing any evidence of being able to detect the difference in question when they listen to speech. The lexical representations are in turn separate from prelexical representations, which are also abstract in nature. This follows from evidence that perceptual learning about speaker-specific phoneme realization, induced on the basis of a few words, generalizes across the whole lexicon to inform the recognition of all words containing the same phoneme. The efficiency of human speech processing has its basis in the rapid execution of operations over abstract representations.


Author(s):  
E.M. Waddell ◽  
J.N. Chapman ◽  
R.P. Ferrier

Dekkers and de Lang (1977) have discussed a practical method of realising differential phase contrast in a STEM. The method involves taking the difference signal from two semi-circular detectors placed symmetrically about the optic axis and subtending the same angle (2α) at the specimen as that of the cone of illumination. Such a system, or an obvious generalisation of it, namely a quadrant detector, has the characteristic of responding to the gradient of the phase of the specimen transmittance. In this paper we shall compare the performance of this type of system with that of a first moment detector (Waddell et al.1977).For a first moment detector the response function R(k) is of the form R(k) = ck where c is a constant, k is a position vector in the detector plane and the vector nature of R(k)indicates that two signals are produced. This type of system would produce an image signal given bywhere the specimen transmittance is given by a (r) exp (iϕ (r), r is a position vector in object space, ro the position of the probe, ⊛ represents a convolution integral and it has been assumed that we have a coherent probe, with a complex disturbance of the form b(r-ro) exp (iζ (r-ro)). Thus the image signal for a pure phase object imaged in a STEM using a first moment detector is b2 ⊛ ▽ø. Note that this puts no restrictions on the magnitude of the variation of the phase function, but does assume an infinite detector.


1988 ◽  
Vol 27 (04) ◽  
pp. 151-153
Author(s):  
P. Thouvenot ◽  
F. Brunotte ◽  
J. Robert ◽  
L. J. Anghileri

In vitro uptake of 67Ga-citrate and 59Fe-citrate by DS sarcoma cells in the presence of tumor-bearing animal blood plasma showed a dramatic inhibition of both 67Ga and 59Fe uptakes: about ii/io of 67Ga and 1/5o of the 59Fe are taken up by the cells. Subcellular fractionation appears to indicate no specific binding to cell structures, and the difference of binding seems to be related to the transferrin chelation and transmembrane transport differences


2020 ◽  
Vol 55 (2) ◽  
Author(s):  
Ľubomír Zvada

This Handbook maps the contours of an exciting and burgeoning interdisciplinary field concerned with the role of language and languages in situations of conflict. It explores conceptual approaches, sources of information that are available, and the institutions and actors that mediate language encounters. It examines case studies of the role that languages have played in specific conflicts, from colonial times through to the Middle East and Africa today. The contributors provide vibrant evidence to challenge the monolingual assumptions that have affected traditional views of war and conflict. They show that languages are woven into every aspect of the making of war and peace, and demonstrate how language shapes public policy and military strategy, setting frameworks and expectations. The Handbook's 22 chapters powerfully illustrate how the encounter between languages is integral to almost all conflicts, to every phase of military operations and to the lived experiences of those on the ground, who meet, work and fight with speakers of other languages. This comprehensive work will appeal to scholars from across the disciplines of linguistics, translation studies, history, and international relations; and provide fresh insights for a broad range of practitioners interested in understanding the role and implications of foreign languages in war.


Author(s):  
M. S. Sudakova ◽  
M. L. Vladov ◽  
M. R. Sadurtdinov

Within the ground penetrating radar bandwidth the medium is considered to be an ideal dielectric, which is not always true. Electromagnetic waves reflection coefficient conductivity dependence showed a significant role of the difference in conductivity in reflection strength. It was confirmed by physical modeling. Conductivity of geological media should be taken into account when solving direct and inverse problems, survey design planning, etc. Ground penetrating radar can be used to solve the problem of mapping of halocline or determine water contamination.


Author(s):  
Brian Willems

A human-centred approach to the environment is leading to ecological collapse. One of the ways that speculative realism challenges anthropomorphism is by taking non-human things to be as valid objects of investivation as humans, allowing a more responsible and truthful view of the world to take place. Brian Willems uses a range of science fiction literature that questions anthropomorphism both to develop and challenge this philosophical position. He looks at how nonsense and sense exist together in science fiction, the way in which language is not a guarantee of personhood, the role of vision in relation to identity formation, the difference between metamorphosis and modulation, representations of non-human deaths and the function of plasticity within the Anthropocene. Willems considers the works of Cormac McCarthy, Paolo Bacigalupi, Neil Gaiman, China Miéville, Doris Lessing and Kim Stanley Robinson are considered alongside some of the main figures of speculative materialism including Graham Harman, Quentin Meillassoux and Jane Bennett.


2019 ◽  
Author(s):  
Riccardo Spezia ◽  
Hichem Dammak

<div> <div> <div> <p>In the present work we have investigated the possibility of using the Quantum Thermal Bath (QTB) method in molecular simulations of unimolecular dissociation processes. Notably, QTB is aimed in introducing quantum nuclear effects with a com- putational time which is basically the same as in newtonian simulations. At this end we have considered the model fragmentation of CH4 for which an analytical function is present in the literature. Moreover, based on the same model a microcanonical algorithm which monitor zero-point energy of products, and eventually modifies tra- jectories, was recently proposed. We have thus compared classical and quantum rate constant with these different models. QTB seems to correctly reproduce some quantum features, in particular the difference between classical and quantum activation energies, making it a promising method to study unimolecular fragmentation of much complex systems with molecular simulations. The role of QTB thermostat on rotational degrees of freedom is also analyzed and discussed. </p> </div> </div> </div>


2020 ◽  
Vol 11 (SPL1) ◽  
pp. 171-174
Author(s):  
Tarare Toshida ◽  
Chaple Jagruti

The covid-19 resulted in broad range of spread throughout the world in which India has also became a prey of it and in this situation the means of media is extensively inϑluencing the mentality of the people. Media always played a role of loop between society and sources of information. In this epidemic also media is playing a vital role in shaping the reaction in ϑirst place for both good and ill by providing important facts regarding symptoms of Corona virus, preventive measures against the virus and also how to deal with any suspect of disease to overcome covid-19. On the other hand, there are endless people who spread endless rumours overs social media and are adversely affecting life of people but we always count on media because they provide us with valuable answers to our questions, facts and everything in need. Media always remains on top of the line when it comes to stop the out spread of rumours which are surely dangerous kind of information for society. So on our side we should react fairly and maturely to handle the situation to keep it in the favour of humanity and help government not only to ϑight this pandemic but also the info emic.


Patan Pragya ◽  
2019 ◽  
Vol 5 (1) ◽  
pp. 122-132
Author(s):  
Laxman Singh Kunwer

This paper examines the history and current situation of foreign labour migration in Nepal, which is in increasing trend. This paper highlights on some major push and pull factors, impacts of labour migration and remittances. The role and impacts of remittances in Nepal are also another key issue of this paper. The objective of paper is to discuss historical aspects and highlights the role of remittances in Nepal. The paper is developed with the help of secondary sources of information and discussed only on Nepalese foreign labours. The existing exploitative working environment in destinations of Nepalese migrations labpurs, lack of skills and trainings among labour migrants including government to government agreement between labour sending (Nepal) and labour receiving countries to protect rights of labour migrants also has been discussed. This paper also highlights the need of effective foreign labour policies based on scientific research. There is need of reliable and proper environment of investment of remittances in productive sectors as well as use of migrant's skills and knowledge to achieve prosperity of nation.


Author(s):  
S.A. Kirillina ◽  
A.L. Safronova ◽  
V.V. Orlov

Аннотация В статье изучены общие и специфические черты идейных воззрений, пропагандистской риторики и политических действий представителей халифатистского движения на Ближнем Востоке и в Южной Азии. В ретроспективном ключе прослеживается эволюция представлений о сущности и необходимости возрождения института халифата в трудах исламских идеологов, реформаторов и политиков Джамал ад-Дина ал-Афгани, Абд ар-Рахмана ал-Кавакиби, Мухаммада Рашида Риды, Абул Калама Азада. Внимание авторов сосредоточено на общественно-политических дискуссиях 2030-х годов XX столетия, а также на повестке дня халифатистских конгрессов и конференций этого периода. На них вырабатывались первые представления современников о пост-османском формате мусульманского единства и идейно-политической роли будущего халифата. Авторы демонстрируют различие между моделями реакции мусульман Ближнего Востока и Южной Азии на упразднение османского халифата республиканским руководством Турции. Установлена многоаспектная взаимосвязь между халифатистскими ценностями, проосманскими настроениями и формами самоотождествления, которые сложились в арабских и южноазиатских обществах. Отдельно намечено соотношение между подъемом халифатистских настроений и радикализацией антиколониальных действий мусульман Индостана.Abstract The article deals with analysis of common and specific features of ideas, propaganda, rhetoric and political actions taken by representatives of the movement for defense of the Caliphate in the Middle East and South Asia. The retrospection showing the transformation of conception of the Caliphate and the necessity of its revival in the works of eminent ideologists and politicians of the Muslim world Jamal al-Din al-Afghani, Abd al-Rahman al-Kawakibi, Muhammad Rashid Rida and Abul Kalam Azad, is also given in the article. The authors also focus on the social and political discussions of the 1920s 1930s, as well as on the agenda of Caliphatist congresses and conferences of this period. They helped to elaborate the early representations of post-Ottoman pattern of the Muslim unity and the ideological and political role of the future Caliphate. The authors demonstrate the difference between the forms of reaction of Muslims in the Middle East and South Asia to the repudiation of the Caliphate by the Republican leaders of Turkey. The article establishes a multi-aspect interaction between the Caliphatist values and forms of self-identification, emerged in Arab and South Asian societies. The correlation between the rise of Caliphatist attitudes and radicalization of anti-colonial actions of South Asian Muslims is also outlined.


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