Estimation of Time-to-Contact from Retinal Flow

Perception ◽  
1997 ◽  
Vol 26 (1_suppl) ◽  
pp. 169-169
Author(s):  
M G Harris

We investigated four models for estimating time-to-contact (TTC) from retinal flow. Lee's model can deal with sparse flow but fails if the flow contains a rotational component. Koenderink's model, based on div, can deal with rotation but fails if the flow is sparse or if the world does not vary coherently in depth. Two new models were developed by representing retinal flow as the sum of an expansion and a rotation component. The first operates on pairs of points and can deal with sparse flow but fails if the world does not vary coherently in depth. Uniquely, this model provides TTC estimates without prior knowledge of either the focus of expansion (FOE) or focus of rotation (FOR). The second model estimates both the FOE and the FOR and then operates on a point-by-point basis. This model can deal with incoherent depth variations. We compared human performance with these different model properties by requiring subjects to estimate FOE and TTC from random-dot kinematograms. We used kinematograms depicting smooth planes and random 3-D clouds of points, and systematically varied the density of the flow. Performance was not substantially reduced by sparse flow or by incoherent depth, which argues against Koenderink's and the first of our own models. Performance remained good when rotation was added to the flow, which argues against Lee's model. Overall, the data favour a model that first decomposes flow into expansion and rotation components and then estimates TTC on a point-by-point basis.

2017 ◽  
Vol 73 (3) ◽  
Author(s):  
Joerg Rieger ◽  
Rosemarie Henkel-Rieger

Across the globe, conditions of labour are worsening, providing both challenges and opportunities. As labour is one of the places where the intersectionality of race, ethnicity, gender, sexuality, and class is always at work, new models of resistance are created here as well. Deep solidarity describes what happens when the 99% who have to work for a living (including people who are excluded from the job market) realise what they have in common, in order to employ their differences productively in the struggle. In this article, a theologian and a labour and community organiser work together showing how the Abrahamic religious traditions and developments in the world of labour help us to shape deeper forms of solidarity.


Spatium ◽  
2014 ◽  
pp. 39-46 ◽  
Author(s):  
Dzemila Beganovic

Contemporary urban development has changed the traditional cities all over the world. In our region, the typical Balkan cities of oriental origin, structure and outlook were almost totally transformed in the second half of the 20th century. Modern movement brought new models of urban organization, different communication concepts and a variety of concepts of modern buildings. Among others, the idea of complex urbarchitectonic structures in urban tissue spread under specific influences and models. After a short review of modern urban development and the idea of complex urban structures, this paper explores urban transformation of less researched cities such as Pristina and Novi Pazar. The focus is on the phenomenon of complex urbarchitectonic structures built in related cities in a short period from 1969-1989. Four complex urbarchitectonic structures will be presented: Kicma and complex in JNA Street in Pristina and Lucne buildings and Jezero buildings in Novi Pazar.


10.28945/2961 ◽  
2006 ◽  
Author(s):  
Tanja Krunic ◽  
Ljiljana Ruzic-Dimitrijevic ◽  
Branka Petrovic ◽  
Robert Farkas

The Advanced Technical School from Novi Sad set up a completely new study group for web design in 2004. The paper explains its organization and gives course descriptions. When it was established, there were not many similar groups in the world exclusively dealing with web design, whose programs could serve as role models, hence the curriculum and syllabus had to be based on our own experience. They cover inevitable web issues like usability, user-oriented web design, accessibility, privacy and security, which are briefly discussed in the paper. The purpose of the research referring to web accessibility and privacy presented in one of the sections was to help create the two documents. The students' prior knowledge was also an important parameter in their writing. The curriculum and syllabus have been updated recently, and the improved version given herein will be in use from the next academic year.


Ritið ◽  
2019 ◽  
Vol 19 (2) ◽  
pp. 43-68
Author(s):  
Gunnar Tómas Kristófersson

The article addresses the early years of film in iceland, where the goal is to deepen our knowledge of the main participants in introducing and promoting cinema in iceland at the turn of the 19th century. Two years spanning a three-year period mark the beginnings of the age of film in iceland. The former is 1901 when the Dutch filmmaker F. A. Nöggerath came to film iceland and icelanders for an English film company. The latter year is 1903, when the Norwegian, Rasmus Hallseth and the Swede David Fernander, traveled around the country to screen films for the first time in iceland. These two visits mark the emergence of cinema in iceland. iceland-ers had little prior knowledge of the new medium, which was getting to be widely known around the world, apart from the coverage of newspapers and stories of lucky icelanders who had experienced film screenings abroad. Shows using a predecessor of film, the magic lantern, were held by Sigfús Eymundsson and Þorlákur ó. Jo-hnson in the 19th century. After the introduction of films in 1903, several people put together funds to buy Hallseth’s and Fernanders’ equipment and began to exhibit films on their own. However, daily performances did not happen until Reykjavik Biograftheater (later ,,Gamla Bíó”) was established in 1906. After several attempts by various parties to hold regular screenings in Reykjavik, one could say that cinema did not properly settle in iceland until the establishment of Nýja Bíó in 1913.


Author(s):  
Brian Rogers

The ability to detect motion is one of the most important properties of our visual system and the visual systems of nearly every other species. Motion perception is not just important for detecting the movement of objects—both for catching prey and for avoiding predators—but it is also important for providing information about the 3-D structure of the world, for maintaining balance, determining our direction of heading, segregating the scene and breaking camouflage, and judging time-to-contact with other objects in the world. ‘Motion perception’ describes the spatio-temporal process of motion perception and the perceptual effects that tell us something about the characteristics of the motion system: apparent motion, the motion after-effect, and induced motion.


2019 ◽  
pp. 191-205 ◽  
Author(s):  
Jakob Hohwy

Andy Clark’s exciting work on predictive processing provides the umbrella under which his hugely influential previous work on embodied and extended cognition seeks a unified home. This chapter argues that in fact predictive processing harbours internalist, inferentialist and epistemic tenets that cannot leave embodied and extended cognition unchanged. Predictive processing cannot do the work Clark requires of it without relying on rich, preconstructive internal representations of the world, nor without engaging in paradigmatically rational integration of prior knowledge and new sensory input. Hence, next to Clark’s image of fluid “uncertainty surfing” is an equally valid image of more emaciated and plodding world-modelling. Rather than underpinning orthodox embodied and extended approches, predictive processing therefore presents an opportunity for a potentially fruitful new synthesis of cognitivist and embodied approaches to cognition.


Foods ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 417 ◽  
Author(s):  
Serafín J. Cruces-Montes ◽  
Ana Merchán-Clavellino ◽  
Antonio Romero-Moreno ◽  
Alberto Paramio

The wine with the designation of origin “Jerez-Xerez-Sherry” is one of the most produced in Spain and with a greater volume of exports abroad. This study analyzes the preferences of Sherry Wine and its different varieties, based on gender and knowledge and interest in the world of wine. Similarly, the influence of the attributes of Sherry Wine on its choice and consumption is investigated. For this purpose, 1502 participants (1407 wine consumers) were recruited; among the consumers, 58.5% are women, and 74.3% have little knowledge of wine (Mean age 22.6; SD = 3.07; range 18–30). Data collection was done through an online survey. The results reveal that among the types of wines from Sherry, the Fino and the Manzanilla are the most chosen. The young people who have the highest consumption of wine are those who have the most prior knowledge of wine. Also, these young people attribute their choice of wine to intrinsic factors, and even women and connoisseurs are more important in this type of dimension. But the importance of the attributes differs according to the types of wines (Fino/Cream—flavor, Palo Cortado/Pedro Ximénez—color, Amontillado/Manzanilla—price and Oloroso—prizes). These findings will allow establishing measures for their promotion, as well as for the design and specific sales strategies for each type of wine.


Author(s):  
Gunilla Bradley

Creating the global village very much attach to a macroergonomic approach to work life issues theoretically, empirically and in action. The underlying paradigm in macroergonomics is very much the same in various countries and may only differ regarding terminology. In this symposium we will enjoy the experiences from the North American pioneers and one Japanese pioneer. The world around us is being transformed during the past few years. Technical development, primarily within the information and communication area, is both a prerequisite and a driving force for the internationalization and globalization of economy, trade, science and culture. At the same time on another level the development of new technology, advanced and widespread use of computer technology and telecommunication and the convergence of these technologies have a profound impact on organizational and quality aspects of our lives today both at work and at home. New application areas within information industry are emerging in the integration of communications, computer and media. The span of control for human intervention might seem to shrink when we take use of more integrated technical solutions. On the other hand the structures in work life built during the industrialized era seem to break down and new organizational structures characterized by networking and virtual organizations, are offering new forms for human influence and interventions. Education and training have a key role for taking advantage of the opportunities and foreseeing the risks. Recent discussions about the role of ergonomists have centered around our role as change agents who are also trained as scientists. This scientist/practitioner dual identity can cause difficulties in implementing ergonomics. The purpose of this panel is to present macroergonomic strategies for creating change. Panelists will present structural, strategic, and participatory macroergonomic approaches. These approaches provide a larger framework from which we can understand our role, our research, ergonomic knowledge, and how to implement meaningful change in organizations. Without this overarching framework, ergonomics remains an interesting but impractical means for example in the field of transferring technology. Moreover these implementation issues confront people everyday in the expansion of organizations and technology across an ever shrinking global village. With or without ergonomic input, people and organizations are making changes every day that profoundly influence human performance and behavior. There are many examples that these change efforts fail. The papers will argue that these failures are rooted in the technical, structural and process focus of these changes, without considering the human. The macroergonomic strategies to be presented suggest routes on a larger road map to create meaningful change. This is even more important in the near future, when goals of sustainable environments are set. When capital and technology as well as people become increasingly and rapidly mobile at the global level, the strength of the local competence and know-how environment will become of greater significance for the development and prosperity of the individual countries and for the living conditions of their citizens. Competence to cope with the rapid pace of change will become ever more essential. Global villages are being created in the countryside around the world, with the use of information technology. Electronic marketplaces are used to strengthen small enterprises, to create new professional roles, and to strengthen the citizen's role. Adapting a perspective of macroergonomics is crucial. Guiding principles for a national information technology investment are formulated both in USA and Europe where also questions are brought up regarding information support for innovative industry, distance education, decentralized work and distributed civic information.


2021 ◽  
Vol 22 (9) ◽  
pp. 1060-1070
Author(s):  
M. P. Bushmakina

A review of the current obstetric and gynecological literature in recent years unwittingly draws attention to the outstanding interest shown by biologists around the world in issues of human performance.


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