566 resultados para circles


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该文以一实际应用为背景提出了多移动机器人避碰及死锁预防算法 ,该算法将机器人的运行环境形式化地描述为初等运动集、冲突图、总任务集及机器人作业集 ,利用集合论、图论的有关方法及技术实现了多机器人间的避碰与死锁预防 .当机器人的运行环境改变时 ,只需要对相应的集合描述文件进行修改 ,而不用对程序做任何改动 .算法的另一个特点是利用避碰算法巧妙地完成了死锁预防 .仿真和实际运行证明了该算法高效可靠 .

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相机标定是2D图像重建3D测度信息的关键步骤,也是一项耗时的任务,由于标定过程中经常需要人工寻找对应点。本文提出了一种基于圆形标志点的全自动相机标定方法。首先,在传统圆形标志点模板的基础上增设了5个方位圆。然后提出了新标定板下图像特征点的自动检测和匹配算法。匹配结果直接作为Zhang的算法的输入,从而计算出相机内外参数,避免了标定过程的人工干预。最终实验结果显示了所提方法在不同场景和光照条件下的自动性和正确性。

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As a part of Gangdisi-Nianqingtanggula plate, Cuoqin basin (N 29°3O'~33°20'; E 80°~90°) is situated in the west of the Tibet autonomous Region, with an area of 100000 square kilometers. Cretaceous shallow-water carbonate is widely distributed in this basin. Its accumulative thickness is more than 1000 meters. Sedimentary facies of cretaceous shallow-water carbonate and carbon isotope feature are studied in details here. On basis of two main sections researched comprehensively, five facies marks are found. With the combination of Wilson's model and ramp model, a platform-mild slope model are put forward, which is thought to be a comprehensive model for this area. There are three sedimentary circles which are comprised of terrestrial clastic tidal flat and carbonate platform facies in Duoba Member of Duoni Formation. Langshan Formation is mainly comprised of carbonate platform facies. We also studied the carbon isotope features influenced by Cretaceous Aptian-Albian's oceanic anoxic events (OAE). After correlating the δ~(13)C curves of the studied section with that of Peregrina Canyon section in Mexico, we find that there are similar δ~(13)C curves fluctuation styles, namely there is also a δ~(13)C positive excursion in shallow-water carbonate in the studied area, and the degree of δ~(13)C positive excursion in shallow-water carbonate is much higher. There are two main causes which should interpret above δ~(13)C positive excursion feature: on the one hand ,much organic carbon take much 12C off when they are buried with a higher speed during the OAE, which lead to the ~(12)C rise of oceanic total dissolved carbon (TDC),on the other hand, during the OAE there are stratification structures in pale-ocean, in the upper mixed layer with high carbon fixation (HCML). There are so much plankton organisms which absorb much ~(12)C as the ~(13)C of shallow-water carbonate in this layer rise higher. Furthermore, on the basis of the theories of carbonate isotope strata, we suggest that the currently used boundary between Aptian and Albian in the studied area is possibly above the international one, which means the main parts of Duoba Member of Duoni Foramatiom in this area should be belong to Albian in stead of Aptian.

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In this study we examined samples of sandy sediments along the north-south transects crossing the Taklimakan Desert, the Badain Jaran Desert and the Hunshandake Sandy Land respectively. The grain size was measured via dry sieving, and the carbonate content by means of an Eijkelkamp instrument. The analyses of grain size and carbonate contents show: (1) The sand grains of the Badain Jaran Desert are coarsest and best sorted, this should be associated with the strongest usual wind among these three regions. (2) The different desert have its special wind condition in their own regions. The Badain Jaran Desert and the Taklimakan Desert both show that the wind is getting weaker from north towards south, but the Hunshandake Sandy Land have the similar wind stress from north towards south. (3) The frequency curves of the sandy sediments from the Badain Jaran Desert show a kind of distinct double peaks, presumably associated with the alternative transportations of summer and winter monsoons in the north boundaries of the summer monsoon. (4) There are great differences of the carbonate contents among these three regions, this maybe associated with the humidity, the humidity of Hunshandake Sandy Land is the best, and the one of the Taklimakan Desert would be the worst among them. Analyses of The three profiles about grain size and carbonate contents show: (1) From 8ka BP, the winter-monsoon was getting weaker, and the summer-monsoon accordingly became stronger, and about 1 ka later, the winter-monsoon was getting stronger again. (2) In the stage of the profiles, there maybe show two circles of dry and wet climate, and the climate changes in those three regions show the similar trend.

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Brand placement is to present the information of products and brands through certain entertainments and non-commercial areas. Since 1990's, brand placement has become a major way of spreading advertisement and a new growing point of the global advertising market. In china, it is easily seen from spring festival evening gala of CCTV to all kinds of movie and TV shows, and is thus interested by many brand owners, advertisers and communication researchers. Since 2006, the people in the media circles have begin to take full care of the study of the brand placement. In general, there is still certain distance between the theoretical studies and the reality. It's a general problem over the world and is especially true for China as this was just a new idea. As the biggest global economic entity, China is the most potential and powerful market, thus the market of the brand placement will be huge. To push its development, it's then crucial to have theoretical studies on it. Many questions have not been explained yet in this area, mostly essential is to ask what kind of advantage it acquires compared with the traditional advertisement, if there is, how does such advantage show? What kind of factors influents the market effect of the brand placement? All these questions are not answered yet. Also it's well-known that a successful advertisement relies heavily on the understanding of the culture. Thus a specific thing to deal with is to study the effects according to the Chinese culture, which can make constructive suggestion to the whole industry. Our research is to compare the effects between the brand placement with the ordinary media advertisements, discuss its possible influences, and try to make certain suggestions to the future running and development. Our research obtains the following results by using the movie and advertisement in reality: (1) Like ordinary media ad’s, brand placement can improve the brand recognition of the audience significantly. (2) The ordinary ad's make the people easier to remember them than brand placement, while not too much difference in the brand recognition. (3) The brand placement has a significant 'emotional shifting' effect, i.e. the more positive to the movie, the more you love the built-in brand. (4) It is an important factor that how much brand information is involved in the movie; while how much the plot is involved has great impact on the 'emotional shifting' effect. (5) The familiarity is a great factor for the ad's, it's obvious that the popular products get way better effects through brand replacement. (6) An effective way is to choose those positive, interesting and eye-catching movies and TV shows as carriers of the brand and to use it as natural as possible.

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We describe a software package for computing and manipulating the subdivision of a sphere by a collection of (not necessarily great) circles and for computing the boundary surface of the union of spheres. We present problems that arise in the implementation of the software and the solutions that we have found for them. At the core of the paper is a novel perturbation scheme to overcome degeneracies and precision problems in computing spherical arrangements while using floating point arithmetic. The scheme is relatively simple, it balances between the efficiency of computation and the magnitude of the perturbation, and it performs well in practice. In one O(n) time pass through the data, it perturbs the inputs necessary to insure no potential degeneracies and then passes the perturbed inputs on to the geometric algorithm. We report and discuss experimental results. Our package is a major component in a larger package aimed to support geometric queries on molecular models; it is currently employed by chemists working in "rational drug design." The spherical subdivisions are used to construct a geometric model of a molecule where each sphere represents an atom. We also give an overview of the molecular modeling package and detail additional features and implementation issues.

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The digital divide has been, at least until very recently, a major theme in policy as well as interdisciplinary academic circles across the world, as well as at a collective global level, as attested by the World Summit on the Information Society. Numerous research papers and volumes have attempted to conceptualise the digital divide and to offer reasoned prescriptive and normative responses. What has been lacking in many of these studies, it is submitted, is a rigorous negotiation of moral and political philosophy, the result being a failure to situate the digital divide - or rather, more widely, information imbalances - in a holistic understanding of social structures of power and wealth. In practice, prescriptive offerings have been little more than philanthropic in tendency, whether private or corporate philanthropy. Instead, a theory of distributive justice is required, one that recovers the tradition of emancipatory, democratic struggle. This much has been said before. What is new here, however, is that the paper suggests a specific formula, the Rawls-Tawney theorem, as a solution at the level of analytical moral-political philosophy. Building on the work of John Rawls and R. H. Tawney, this avoids both the Charybdis of Marxism and the Scylla of liberalism. It delineates some of the details of the meaning of social justice in the information age. Promulgating a conception of isonomia, which while egalitarian eschews arithmetic equality (the equality of misery), the paper hopes to contribute to the emerging ideal of communicative justice in the media-saturated, post-industrial epoch.

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The digital divide continues to challenge political and academic circles worldwide. A range of policy solutions is briefly evaluated, from laissez-faire on the right to “arithmetic” egalitarianism on the left. The article recasts the digital divide as a problem for the social distribution of presumptively important information (e.g., electoral data, news, science) within postindustrial society. Endorsing in general terms the left-liberal approach of differential or “geometric” egalitarianism, it seeks to invest this with greater precision, and therefore utility, by means of a possibly original synthesis of the ideas of John Rawls and R. H. Tawney. It is argued that, once certain categories of information are accorded the status of “primary goods,” their distribution must then comply with principles of justice as articulated by those major 20th century exponents of ethical social democracy. The resultant Rawls-Tawney theorem, if valid, might augment the portfolio of options for interventionist information policy in the 21st century

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Edwards, Huw, Gwaith Madog Dwygraig (Canolfan Uwchefrydiau Cymreig a Cheltaidd Prifysgol Cymru, 2007)

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Zadaniem artykułu jest ukazanie dorobku piśmiennictwa pszczelniczego na Śląsku. Pretekstem do poruszenia tego tematu jest przypadająca w 2011 roku dwusetna rocznica urodzin wybitnego pszczelarza Jana Dzierżona. Osoba i dokonania najsłynniejszego chyba w świecie Ślązaka do tego stopnia zdominowały historię pszczelarstwa tego regionu, że właściwie bardzo niewiele mówi się o dorobku innych działających aktywnie śląskich pszczelarzach praktykach i publicystach. Tymczasem dorobek ten jest imponujący. W części pierwszej artykułu przypomniano Nickela Jacoba ze Szprotawy, autora pierwszej wydanej na Śląsku książki pszczelarskiej, uznanego jednocześnie za ojca niemieckiej bibliografii pszczelarskiej. Wśród pionierów niemieckiej literatury fachowej dotyczącej pszczół znajduje się też Johann Coler ze Złotoryi. W XVIII wieku swą działalność praktyczną i publicystyczną w znacznej mierze związali ze Śląskiem Łużyczanin Adam Gottlieb Schirach i Niemiec Johann Riem. W dziełach innych autorów z zakresu gospodarstwa wiejskiego pojawiają się również fragmenty poświęcone pszczelarstwu. Dorobek swych poprzedników wzbogacił i swą działalnością rozsławił śląskie pszczelarstwo ksiądz dr Jan Dzierżon, odkrywca partenogenezy, konstruktor nowoczesnego ula, autor licznych publikacji. „Księciu pszczół” poświęcona została druga część artykułu. Przedstawiono w niej pokrótce jego życie i działalność, dzieje walki o uznanie teorii partenogenezy, ogromny dorobek publicystyczny. Wskazano jednocześnie na brak opracowania pełnej bibliografii podmiotowej. Dzierżon był wydawcą jednego z pierwszych na Śląsku czasopism pszczelarskich. Dorobek śląskiego czasopiśmiennictwa pszczelarskiego jest bogaty i dziwi fakt, że właściwie w bardzo małym dotychczas stopniu został poznany. Część trzecią poświęcono niemieckim i polskim czasopismom pszczelarskim wydawanym na Śląsku. Uwzględniono tutaj tytuły samoistne oraz dodatki. W podsumowaniu wykazano, że we wszystkich obszarach bibliografia piśmiennictwa śląskiego wymaga kompleksowego rozpoznania. Stan opracowania piśmiennictwa pszczelarskiego na Śląsku stanowi w pewnej mierze odbicie stanu bibliografii tego zagadnienia na ziemiach polskich.

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The present work examines the beginnings of ancient hermeneutics. More specifically, it discusses the connection between the rise of the practice of allegoresis, on the one hand, and the emergence of the first theory of figurative language, on the other. Thus, this book investigates the specific historical and cultural circumstances that enabled the ancient Greeks not only to discover the possibility of allegorical interpretation, but also to treat figurative language as a philosophical problem. By posing difficulties in understanding the enigmatic sense of various esoteric doctrines, poems, oracles and riddles, figurative language created the context for theoretical reflection on the meaning of these “messages”. Hence, ancient interpreters began to ponder over the nature and functions of figurative (“enigmatic”) language as well as over the techniques of its proper use and interpretation. Although the practice of allegorical interpretation was closely linked to the development of the whole of ancient philosophy, the present work covers only the period from the 6th to the 4th century B.C. It concentrates, then, on the philosophical and cultural consequences of allegoresis in the classical age. The main thesis advocated here has it that the ancient Greeks were in-clined to regard allegory as a cognitive problem rather than merely as a stylistic or a literary one. When searching for the hidden meanings of various esoteric doc-trines, poems, oracles and riddles, ancient interpreters of these “messages” assumed allegory to be the only tool suitable for articulating certain matters. In other words, it was their belief that the use of figurative language resulted from the necessity of expressing things that were otherwise inexpressible. The present work has been organized in the following manner. The first part contains historical and philological discussions that provide the point of departure for more philosophical considerations. This part consists of two introductory chapters. Chapter one situates the practice of allegorical interpretation at the borderline of two different traditions: the rhetorical-grammatical and the hermeneutical. In order to clearly differentiate between the two, chapter one distinguishes between allegory and allegoresis, on the one hand, and allegoresis and exegesis, on the other. While pointing to the conventionality (and even arbitrariness) of such distinctions, the chapter argues, nevertheless, for their heuristic usefulness. The remaining part of chapter one focuses on a historical and philological reconstruction of the most important conceptual tools of ancient hermeneutics. Discussing the semantics of such terms as allēgoría, hypónoia, ainigma and symbolon proves important for at least two crucial reasons. Firstly, it reveals the mutual affinity between allegoresis and divination, i.e., practices that are inherently connected with the need to discover the latent meaning of the “message” in question (whether poem or oracle). Secondly, these philological analyses bring to light the specificity of the ancient understanding of such concepts as allegory or symbol. It goes without saying that antiquity employed these terms in a manner quite disparate from modernity. Chapter one concludes with a discussion of ancient views on the cognitive value of figurative (“enigmatic”) language. Chapter two focuses on the role that allegoresis played in the process of transforming mythos into logos. It is suggested here that it was the practice of allegorical interpretation that made it possible to preserve the traditional myths as an important point of reference for the whole of ancient philosophy. Thus, chapter two argues that the existence of a clear opposition between mythos into logos in Preplatonic philosophy is highly questionable in light of the indisputable fact that the Presocratics, Sophists and Cynics were profoundly convinced about the cognitive value of mythos (this conviction was also shared by Plato and Aristotle, but their attitude towards myth was more complex). Consequently, chapter two argues that in Preplatonic philosophy, myth played a function analogous to the concepts discussed in chapter one (i.e., hidden meanings, enigmas and symbols), for in all these cases, ancient interpreters found tools for conveying issues that were otherwise difficult to convey. Chapter two concludes with a classification of various types of allegoresis. Whilst chapters one and two serve as a historical and philological introduction, the second part of this book concentrates on the close relationship between the development of allegoresis, on the one hand, and the flowering of philosophy, on the other. Thus, chapter three discusses the crucial role that allegorical interpretation came to play in Preplatonic philosophy, chapter four deals with Plato’s highly complex and ambivalent attitude to allegoresis, and chapter five has been devoted to Aristotle’s original approach to the practice of allegorical interpretation. It is evident that allegoresis was of paramount importance for the ancient thinkers, irrespective of whether they would value it positively (Preplatonic philosophers and Aristotle) or negatively (Plato). Beginning with the 6th century B.C., the ancient practice of allegorical interpretation is motivated by two distinct interests. On the one hand, the practice of allegorical interpretation reflects the more or less “conservative” attachment to the authority of the poet (whether Homer, Hesiod or Orpheus). The purpose of this apologetic allegoresis is to exonerate poetry from the charges leveled at it by the first philosophers and, though to a lesser degree, historians. Generally, these allegorists seek to save the traditional paideia that builds on the works of the poets. On the other hand, the practice of allegorical interpretation reflects also the more or less “progressive” desire to make original use of the authority of the poet (whether Homer, Hesiod or Orpheus) so as to promote a given philosophical doctrine. The objective of this instrumental allegoresis is to exculpate philosophy from the accusations brought against it by the more conservative circles. Needless to say, these allegorists significantly contribute to the process of the gradual replacing of the mythical view of the world with its more philosophical explanation. The present book suggests that it is the philosophy of Aristotle that should be regarded as a sort of acme in the development of ancient hermeneutics. The reasons for this are twofold. On the one hand, the Stagirite positively values the practice of allegoresis, rehabilitating, thus, the tradition of Preplatonic philosophy against Plato. And, on the other hand, Aristotle initiates the theoretical reflection on figurative (“enigmatic”) language. Hence, in Aristotle we encounter not only the practice of allegoresis, but also the theory of allegory (although the philosopher does not use the term allēgoría). With the situation being as it is, the significance of Aristotle’s work cannot be overestimated. First of all, the Stagirite introduces the concept of metaphor into the then philosophical considerations. From that moment onwards, the phenomenon of figurative language becomes an important philosophical issue. After Aristo-tle, the preponderance of thinkers would feel obliged to specify the rules for the appropriate use of figurative language and the techniques of its correct interpretation. Furthermore, Aristotle ascribes to metaphor (and to various other “excellent” sayings) the function of increasing and enhancing our knowledge. Thus, according to the Stagirite, figurative language is not only an ornamental device, but it can also have a significant explanatory power. Finally, Aristotle observes that figurative expressions cause words to become ambiguous. In this context, the philosopher notices that ambiguity can enrich the language of a poet, but it can also hinder a dialectical discussion. Accordingly, Aristotle is inclined to value polysemy either positively or negatively. Importantly, however, the Stagirite is perfectly aware of the fact that in natural languages ambiguity is unavoidable. This is why Aristotle initiates a syste-matic reflection on the phenomenon of ambiguity and distinguishes its various kinds. In Aristotle, ambiguity is, then, both a problem that needs to be identified and a tool that can help in elucidating intricate philosophical issues. This unique approach to ambiguity and figurative (“enigmatic”) language enabled Aristotle to formulate invaluable intuitions that still await appropriate recognition.

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„We are paying a high price for the increasingly unequivocal equation drawn between knowledge and science and ordinary market product. The ideal of perfectly unrestrained cognition, the true mother of science, is threatened by the mass drive towards practical use and application of knowledge, a looming departure into nothingness. Politicians and managers of scientific life are guilty of considerable contribution in corrupting respectable university structures, and thus undermining culture of science and scholarly ethics. (…). Acquisition of funds, sponsorship, media presence, popularisation or even striving for commercial gain are recognised by politicians and scientific consultants, but most of all they are accepted by the university management as objectives worthy of effort, not to say the foremost goals of science. University rectors are nowadays interested primarily in the amounts of acquired moneys. The outcomes of research thus financed is subject to virtually no control, nor does it arouse any interest, unless it turns out to be fit to be announced in the media as a sensation, thereby serving the ‘prestige’ of the university”.

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Emotional and attentional functions are known to be distributed along ventral and dorsal networks in the brain, respectively. However, the interactions between these systems remain to be specified. The present study used event-related functional magnetic resonance imaging (fMRI) to investigate how attentional focus can modulate the neural activity elicited by scenes that vary in emotional content. In a visual oddball task, aversive and neutral scenes were presented intermittently among circles and squares. The squares were frequent standard events, whereas the other novel stimulus categories occurred rarely. One experimental group [N=10] was instructed to count the circles, whereas another group [N=12] counted the emotional scenes. A main effect of emotion was found in the amygdala (AMG) and ventral frontotemporal cortices. In these regions, activation was significantly greater for emotional than neutral stimuli but was invariant to attentional focus. A main effect of attentional focus was found in dorsal frontoparietal cortices, whose activity signaled task-relevant target events irrespective of emotional content. The only brain region that was sensitive to both emotion and attentional focus was the anterior cingulate gyrus (ACG). When circles were task-relevant, the ACG responded equally to circle targets and distracting emotional scenes. The ACG response to emotional scenes increased when they were task-relevant, and the response to circles concomitantly decreased. These findings support and extend prominent network theories of emotion-attention interactions that highlight the integrative role played by the anterior cingulate.