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“一”与“多”二难文化困境下的族类文化策略——后现代语境中文化绝对主义和相对主义之争的哲学反思 被引量:1
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作者 张再林 张兵 《陕西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2012年第3期53-59,共7页
在后现代哲学的竞争游戏中,由单一主体所谱写的一元文化体系被相对主义离析为与形形色色主体所对应的多元文化,然而多元文化只是其所攻击的一元文化的"地方版"而已。后现代哲学的系谱学分析披露了一元文化和多元文化的"... 在后现代哲学的竞争游戏中,由单一主体所谱写的一元文化体系被相对主义离析为与形形色色主体所对应的多元文化,然而多元文化只是其所攻击的一元文化的"地方版"而已。后现代哲学的系谱学分析披露了一元文化和多元文化的"发家史",但没有展示出摆脱这一文化困境的可能路径。只有基于中国式"家系学"基础上的族类文化,才能有望摆脱文化绝对主义和文化相对主义二极振荡的二难文化困境,也才能真正实现不同文化间"万物并育而不相害,道并行而不悖"的文化和谐。 展开更多
关键词 一元文化 多元文化 文化绝对主义 文化相对主义 家系学 族类文化
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A Triangular Model for Social Work Groups: Teaching the Forgotten Practice Modality
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作者 Billy P. Blodgett Henry Poduthase 《Journalism and Mass Communication》 2015年第4期176-180,共5页
Social Work students typically enroll in the required practice methods courses that are specified by the Council on Social Work Education. At least in the majority of BSW Programs, these practice methods courses are d... Social Work students typically enroll in the required practice methods courses that are specified by the Council on Social Work Education. At least in the majority of BSW Programs, these practice methods courses are divided into micro-level and macro-level sequences. Individual and family systems are covered in the former sequence, while communities and organizations are the systems of focus in the latter sequence. The group system is often minimized and/or completely ignored in the process, even though there may be some reference made to groups in both practice methods sequences. Consequently, the mezzo-level system of groups is only given "lip-service" in the dyadic division of micro and macro-level practice. Furthermore, students often do not have the opportunity to practice in group settings, much less, develop competency in these professional venues. This paper describes a teaching format used in a BSW Program in an effort to ensure student competency as required in a Groups Practice course. The triangular model includes: (1) Classroom teaching of theory; (2) Practice of group dynamics; and (3) Supervision by instructors and MSW students. 展开更多
关键词 GROUPS TEACHING PRACTICE SUPERVISION monitoring evaluation
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Mathematical models and expert system for grate-kiln process of iron ore oxide pellet production(Part Ⅰ):Mathematical models of grate process 被引量:4
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作者 王祎 范晓慧 陈许玲 《Journal of Central South University》 SCIE EI CAS 2012年第4期1092-1097,共6页
Grate process is an important step in grate-kiln pellet production.However,as a relatively closed system,the process on grate is inaccessible to direct detection,therefore,it is hard to control.As a result,mathematica... Grate process is an important step in grate-kiln pellet production.However,as a relatively closed system,the process on grate is inaccessible to direct detection,therefore,it is hard to control.As a result,mathematical models of temperature distribution,moisture distribution and oxidation degree distribution in pellet bed,with good universality,computation speed and calculation accuracy,are presented based on analysis of heat transfer and physical-chemical reactions during grate process.And real-time visualization of temperature,moisture and oxidation degree distribution in pellet bed during grate process is realized.Model validation is displayed,and the similarity of 91% is proved.The results can reveal real time status on grate,and provide a solid foundation for the subsequent study of artificial intelligence control system of pellet production. 展开更多
关键词 mathematical model temperature distribution moisture distribution oxidation degree distribution iron ore oxide pellet
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Quality index of bedded and joint-bearing rock mass and its applications
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作者 姜福兴 秦忠诚 蒋国安 《Journal of Coal Science & Engineering(China)》 2002年第2期12-16,共5页
Based on the theory of Fuzzy Mathematics and Expert System, this paper presents the quantitative expression method of bedded and joint bearing rock mass quality "Stratum Quality Index"(SQI for short), and al... Based on the theory of Fuzzy Mathematics and Expert System, this paper presents the quantitative expression method of bedded and joint bearing rock mass quality "Stratum Quality Index"(SQI for short), and also introduces the successful application of the method in estimating stratum movement parameters. 展开更多
关键词 ground control bedding and joint bearing rock mass quality index of stratum
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Expert recommendation system based on analyzing expertise and networks of human resources in National Science & Technology Information Service 被引量:2
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作者 YANG Myung-seok KANG Nam-kyu +3 位作者 KIM Yun-jeong KIM Jae-soo CHOI Kwang-nam KIM Young-kuk 《Journal of Central South University》 SCIE EI CAS 2013年第8期2212-2218,共7页
This work aims to implement expert and collaborative group recommendation services through an analysis of expertise and network relations NTIS. First of all, expertise database has been constructed by extracting keywo... This work aims to implement expert and collaborative group recommendation services through an analysis of expertise and network relations NTIS. First of all, expertise database has been constructed by extracting keywords after indexing national R&D information in Korea (human resources, project and outcome) and applying expertise calculation algorithm. In consideration of the characteristics of national R&D information, weight values have been selected. Then, expertise points were calculated by applying weighted values. In addition, joint research and collaborative relations were implemented in a knowledge map format through network analysis using national R&D information. 展开更多
关键词 human networks network analysis NTIS R&D information
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Heisenberg's Versus Von Neumann's Indeterminism of Quantum Mechanics
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作者 Franz Klaus Jansen 《Journal of Philosophy Study》 2018年第5期240-251,共12页
Irreducible indeterminism is considered by most physicists as an ontological interpretation of quantum mechanics, which attributes inherent indeterminism to elementary paJcticles. This view was extrapolated by von Neu... Irreducible indeterminism is considered by most physicists as an ontological interpretation of quantum mechanics, which attributes inherent indeterminism to elementary paJcticles. This view was extrapolated by von Neumann from the atomocosm to the entire universe. Heisenberg proposed an epistemic interpretation, postulating that indeterminism stems from ambivalent detection systems, rather than being a characteristic of elementary particles Transformative detection that inherently affects the measured phenomena is responsible for the indeterminism in the atomocosm. As the same does not generally hold true in the macrocosm, this discrepancy has led to the notion of the Heisenberg cut. As explained by Heisenberg's microscope example, high-energy light can displace electrons from their atomic shells in the atomocosm, but would not induce the same effect on objects in the macrocosm, thus rendering such detection neutral. Therefore, detection systems are ambivalent in that they can be transformative under the cut and neutral otherwise. Device variation is found under and above the cut and is the essential cause of outcome variability in the macrocosm. Thus, two completely different categories of indeterminism exist simultaneously under the Heisenberg cut, but only one is found above the cut, known as measurement variations of devices. Experimental exploration of elementary paJcticle behaviors is possible only with the help of detection systems. If these systems affect particle characteristics in any way, this would be sufficient to explain the irreducible quantum mechanical indeterminism. Consequently, the true behavior of elementary particles, whether indeterminist or determinist, would never be detectable. Above the cut, on the other hand, variations in device performance are inevitable, due to reducible perturbing factors, inducing measurement wJciation of devices Heisenberg discovered a general principle of ambivalent detection systems, which can also be found in the macrocosm. In the Wilson Cloud Chamber, vapor is an ambivalent detection system, since high-energy charged particles would produce straight tracks, whereas those of lower energy would leave an irregular trace. According to the epistemic interpretation, von Neumann's extrapolation of irreducible quantum mechanical indeterminism to the entire universe would not be necessary, thereby avoiding the uncomfortable conclusion that the entire universe is based on indeterminism 展开更多
关键词 quantum mechanics INDETERMINISM ontic interpretation extrapolation to universe epistemicinterpretation Heisenberg cut detection systems device variations
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AGVs Dispatching Using Multiple Cooperative Learning Agents
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作者 李晓萌 YangYupu 《High Technology Letters》 EI CAS 2002年第3期83-87,共5页
AGVs dispatching, one of the hot problems in FMS, has attracted widespread interest in recent years. It is hard to dynamically schedule AGVs with pre designed rule because of the uncertainty and dynamic nature of AGVs... AGVs dispatching, one of the hot problems in FMS, has attracted widespread interest in recent years. It is hard to dynamically schedule AGVs with pre designed rule because of the uncertainty and dynamic nature of AGVs dispatching progress, so the AGVs system in this paper is treated as a cooperative learning multiagent system, in which each agent adopts multilevel decision method, which includes two level decisions: the option level and the action level. On the option level, an agent learns a policy to execute a subtask with the best response to the other AGVs’ current options. On the action level, an agent learns an optimal policy of actions for achieving his planned option. The method is applied to a AGVs’ dispatching simulation, and the performance of the AGVs system based on this method is verified. 展开更多
关键词 multi agent reinforcement learning multilevel decision AGVs dispatching
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Influencing Factors of Personal Retirement Decision: Perspective of Research Summary
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作者 WANG Kexiang 《International English Education Research》 2016年第5期43-45,共3页
Because the policy of delay retirement is facing demand differences widely, research workers retirement needs and the basic law from the micro perspective will become increasingly important. Based on the demographic c... Because the policy of delay retirement is facing demand differences widely, research workers retirement needs and the basic law from the micro perspective will become increasingly important. Based on the demographic characteristics, family relationships, social and economic factors and professional environment, such as in four dimensions, the article has reviewed the individual retirement decisions affecting factors and its mechanism of action, and summed up the consensus theory and some controversy. In future research, we need to strengthen the cross disciplines and integration, to explore more available research variables, provide a new starting point for further theoretical research and policy making. 展开更多
关键词 retirement decision postponing the retirement influencing factors literature review
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The Transformation of Archival Philosophy and Practice Through Digital Art
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作者 John Charles Ryan 《Journal of Philosophy Study》 2014年第5期373-390,共18页
In many ways, digital practices have precipitated remarkable changes in the global accessibility of art. However, the digital revolution has also radically influenced the conservation processes surrounding art, includ... In many ways, digital practices have precipitated remarkable changes in the global accessibility of art. However, the digital revolution has also radically influenced the conservation processes surrounding art, including archiving, preserving, and remembering. This paper explores the conservation of digital (or "variable media") artworks for the future benefit of culture, with particular reference to creators and viewers of art, as well as participants in interactive artworks. More specifically, this paper focuses on the philosophical and technical approaches adopted by creators, conservators, and philosophers involved in the preservation of variable media artworks. Issues of programming, interoperability between archival systems, and enhanced public access increasingly inform the design of digital archives. Indeed, the continuously shifting technological landscape-marked by the centrality of digital technologies to everyday life-problematizes the preservation of digital art through mainstream museological paradigms. Part of this analysis of digital art conservation will be drawn from the archival philosophies of Boris Groys and Rick Prelinger. 展开更多
关键词 digital art new media CONSERVATION ARCHIVE PHILOSOPHY
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A system dynamics approach for studying the resilience of irrigation systems
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作者 Newton Paulo Bueno 《Chinese Business Review》 2010年第6期14-26,37,共14页
One of the most interesting outcomes from the recent collaboration between natural and social scientists is the concept of resilience, which imported from engineering to ecology. The problem with that concept is that ... One of the most interesting outcomes from the recent collaboration between natural and social scientists is the concept of resilience, which imported from engineering to ecology. The problem with that concept is that it is hard if not impossible to get simple measures for resilience as far as social-ecological systems are complex ones. Using a system dynamics model, the author shows that, for assessing resilience of systems like irrigation systems, it probably helps to see the process of resilience loss as a systemic one, in which dynamics is given by positive self-reinforcing loops, like the one we have labeled in this paper--the death spiral. The author also presents a list of symptoms of collapse in irrigation systems, in order to assess the resilience of those systems, and suggest some future avenues of research on the subject. 展开更多
关键词 system dynamics irrigation systems RESILIENCE institutions human-ecological footprint
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Systematic status of the caridean families Gnathophyllidae Dana and Hymenoceridae Ortmann(Crustacea:Decapoda):a further examination based on molecular and morphological data
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作者 甘志彬 李新正 +3 位作者 寇琦 陈天任 朱嘉豪 黄慧 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第1期149-158,共10页
The four palaemonoid(sub)families Anchistioididae,Gnathophyllidae,Hymenoceridae,and Pontoniinae are similar in morphology,and all live in marine habitats.Their systematic relationships are controversial.In this study,... The four palaemonoid(sub)families Anchistioididae,Gnathophyllidae,Hymenoceridae,and Pontoniinae are similar in morphology,and all live in marine habitats.Their systematic relationships are controversial.In this study,we used sequences from a mitochondrial ribosomal gene(16S rRNA) and three nuclear genes(H3,NaK,and enolase) to explore the phylogenetic relationships of these four taxa.Our tree based on 43 species belonging to 28 genera shows that Gnathophyllidae and Hymenoceridae are nested within Pontoniinae.This result is consistent with evidence from larval morphology.The defining characteristics of Gnathophyllidae and Hymenoceridae,a vestigial or missing mandibular incisor process and a broadened third maxilliped,can also be found in Pontoniinae;conversely,on the basis of published species descriptions,gnathophyllids and hymenocerids meet most of the defining characteristics of Pontoniinae.The peculiar form of the third maxilliped in gnathophyllids and hymenocerids might be the result of adaptive evolution,as these particular features are also present in pontoniines.According to our phylogenetic tree,Anchistioididae are more remote from Pontoniinae,which is consistent with the distinct morphological differences in the pleopods.The pontoniine genera analyzed(together with Gnathophyllidae and Hymenoceridae) are divided into two clades.The members of Clade I exhibit primordial characteristics similar to those of the Palaemoninae,and might be direct descendants of the ancestor of the Pontoniinae;members of Clade II are more specialized. 展开更多
关键词 CRUSTACEA DECAPODA Gnathophyllidae Hymenoceridae Pontoniinae molecular phylogenetics
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Fine Artists ofPanay: A Pioneering Study of Their Works and Lives
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作者 Lucell A. Larawan 《Journal of Literature and Art Studies》 2013年第1期25-41,共17页
This paper documents the works and lives of selected visual artists from Panay provinces. The selection of the artist was based on meeting at least two of the following criteria: (1) The artist should have a major ... This paper documents the works and lives of selected visual artists from Panay provinces. The selection of the artist was based on meeting at least two of the following criteria: (1) The artist should have a major award(s) in any prestigious national fine arts contests which included the MADE (Metrobank Art and Design Excellence), A.AP (Art Association of the Philippines), Petron, GSIS (Government Service Insurance System), and the Biennial Dumaguete Open Terra Cotta Festival contests; (2) He/she should have had one-man or two-man exhibitions at reputed galleries; and (3) He/she should be active in the local art scene, meaning, a continuous schedule of exhibits during the past three years. Mostly self-taught, the artists' artistic inclinations manifested early in childhood when they discovered their talents; this led to their resolve to seriously pursue with enduring fervor their art careers. Their sense of calling amid a less ideal art scene did not give way to the voice of conformity but they have maintained a clear sense of identity and destiny as inspiring art icons in their milieu. The analyses of the works of these artists lead to the observation of the Panayanon artistic tradition. Aside from the formalist descriptions of the artworks' features, the analyses go further into the contextual and evaluative levels that reveal a highly nuanced meaning and semantic richness of the works. The paintings and sculptural pieces of the artists are expressions of their true "voices", fresh innovations that have earned accolades even if these innovations are untamed by the academe 展开更多
关键词 fine artists Panay artistic tradition
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The Chattering Charades of Nature and Nurture: State-of-the-Art in Nonverbal Communication and Its Relationship With Verbal Messages
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作者 Mark Hickson, III 《Journalism and Mass Communication》 2013年第12期813-819,共7页
Employing a qualitative view of issues in nonverbal communication, the author offers an explanation of the nature-nurture debate. The anthropological view, taken by Birdwhistell and others, is compared with a Darwinia... Employing a qualitative view of issues in nonverbal communication, the author offers an explanation of the nature-nurture debate. The anthropological view, taken by Birdwhistell and others, is compared with a Darwinian perspective. In particular, the author looks at how physical appearance, space, and gestures function in a natural way to protect the individuals who are participating in the exchange. Apparent deceit is frequently the result of such interactions. While the traditional arguments arising from religious tenets are discussed, the author explains how the nature approach has been reinforced in the 20th and 21st centuries with DNA and neurological investigations. In the study of nonverbal communication, the arguments about nature and nurture began in the middle of the 20th century with anthropologists, especially Birdwhistell, taking the nurture stance and others taking the nature stance. Ekman's nature stance on kinesics started from premises suggested by Charles Darwin. In large measure, it is because of Ekman's extensive work that the "balance" has somewhat shifted toward a nature view. 展开更多
关键词 deceit PROXEMICS physical appearance NATURE NURTURE
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Preschoolers' Learning Disabilities Assessment: New Perspectives in Computerized Clinical Tools
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作者 Eugenia I. Toki Victoria Zakopoulou Jenny Pange 《Sino-US English Teaching》 2014年第6期401-410,共10页
This study looks into new perspectives in preschoolers' assessment of being at risk for learning disabilities. Precisely, two innovative assessment approaches are examined in order to reveal new research perspectives... This study looks into new perspectives in preschoolers' assessment of being at risk for learning disabilities. Precisely, two innovative assessment approaches are examined in order to reveal new research perspectives. The first tool, a traditional approach, is the "Early Dyslexia Identification Test" and the second tool, a computerized approach, is an lnternet based Speech Pathology Diagnostic Expert System named "APLo". Both evaluate the sectors of phonological awareness, memory, psychomotor development, pre-writing and pre-reading skills in Greek. The findings o f the current study formulate three directions: (1) the complementary of speech language and learning disorders as a systemic approach, (2) the diagnosis of suspicious factors and compatibilities of learning disabilities even at the preschool age, and (3) the application of alternative methods of assessment aiming for a multidimentional approach with the combined prospect and potential of web tools in the early diagnosis and intervention in learning disabilities. 展开更多
关键词 computer-based assessment tools E-ASSESSMENT learning disabilities Greek language PRESCHOOLERS
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Violence in Partnership and Persisting Problems of Assistance
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作者 Hermina Marekova 《Sociology Study》 2016年第9期553-564,共12页
The paper focuses on an attempt to answer questions concerning domestic violence in accordance with the epistemology in contemporary scientific research. The phenomenology of violence is defined with respect to the su... The paper focuses on an attempt to answer questions concerning domestic violence in accordance with the epistemology in contemporary scientific research. The phenomenology of violence is defined with respect to the superficial as well as the essential side of the phenomena. The problems are covered with respect to interdisciplinary relations. We endeavor to open a broader view. The underlying research represents an alternative approach, attempting to reach a cumulative view based on the data acquired from various contexts. In social science research, it is important to look at the social reality not only through the numbers of quantitative research, because social reality is constructed in various ways. The issues of elimination of violence against women in Slovakia are entrenched in the program of various institutions. Based on the performed analysis, inconsistencies in the approach to providing assistance are identified as the most important problem. The paper deals with the institutional issues persisting in dealing with situations and identifies the fundamental failures of social intervention that still exist, among other reasons, due to the stereotypical, discriminatory perceptions of the issues by the competency. 展开更多
关键词 Gender-Based violence ABUSE competencies LEGISLATION REPORTING
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Focuses and trends of the studies on pediatric palliative care:A bibliometric analysis from 2004 to 2018
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作者 Miao Zhang Xiaohan Li 《International Journal of Nursing Sciences》 CSCD 2021年第1期5-14,I0001,共11页
Objectives:To investigate the focuses and trends of the studies on pediatric palliative care(PPC)and provide directions for future research.Methods:Relevant papers about PPC published from 2004 to 2018 were analyzed u... Objectives:To investigate the focuses and trends of the studies on pediatric palliative care(PPC)and provide directions for future research.Methods:Relevant papers about PPC published from 2004 to 2018 were analyzed using bibliometric analysis methods,including co-word analysis,biclustering analysis,and strategic diagram analysis.The included papers were divided into three groups based on the publication time,including 2004-2008,2009-2013,and 2014-2018.Results:A total of 1132 papers were published between 2004 and 2018,and there were 293 papers published between 2004 and 2008,396 between 2009 and 2013,and 443 between 2014 and 2018.There were 42 high-frequency MeSH terms/MeSH subheadings in papers published between 2004 and 2018,including 12 between 2004 and 2008,13 between 2009 and 2013,and 17 between 2014 and 2018.Conclusion:Studies on PPC were making progress,with the increasing number,expanding scope,and uneven global distribution.Integration palliative care into pediatrics,cancer treatments in pediatric oncology,education methods on PPC,and establishment of professional teams were the major themes during 2004e2008,then the themes changed into establishing interventions to enhance the quality of life of the patients and parents,building professional-family relationship,and investigating attitude of health personnel in PPC during 2009-2013 and subsequently turned into communication skills,end-oflife decision making,and guidelines making on PPC during 2014-2018.Underdeveloped and protential themes including effective approaches to deal with the ethical dilemmas,training programs on communication skills,family support and guideline making are worth studying in the future. 展开更多
关键词 BIBLIOMETRICS Communication Decision making Hospice and palliative care nursing NEOPLASMS PARENTS PEDIATRICS Professional-family relations
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BIOHOME: An Accessible House Designed for Assisted Living
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作者 Begona Garcia Zapirain Javier Vicente Saez Amaia Mendez Zorrilla Ibon Ruiz Oleagordia 《Computer Technology and Application》 2011年第2期117-126,共10页
This project describes an integral solution to implement a module-based platform for the control of all the automated systems inside a house and a remote control of the entrance access to this house. A biometrical acc... This project describes an integral solution to implement a module-based platform for the control of all the automated systems inside a house and a remote control of the entrance access to this house. A biometrical access based on the hand veins has been used with a complete local and remote access control system. A technologically ergonomic way to control the house, as well as some biological signal monitoring has also been developed. This has been done by knowing the physical restrictions of the collective who will live in the house. A set of different sensors will control this operation. In order to control all the home automated systems coordinate the whole platform using the TV remote. This project will implement the OSGI standard. This implementation should ensure the system scalability in terms of including new hardware. In addition, a ZibBee networking system has been developed to enable communication between all the sensors, systems and the central processor. 展开更多
关键词 Disabled people ZIGBEE design for all MONITORING radio frequency identification (RFID) biometrics.
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Consensus of Flocks under M-Nearest-Neighbor Rules 被引量:1
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作者 CHEN Chen CHEN Ge GUO Lei 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2015年第1期1-15,共15页
This paper investigates a class of flocks with an M-nearest-neighbor rule,where each agent's neighbors are determined according to M nearest agents with M being a given integer,rather than all the agents within a ... This paper investigates a class of flocks with an M-nearest-neighbor rule,where each agent's neighbors are determined according to M nearest agents with M being a given integer,rather than all the agents within a fixed metric distance as in the well-known Vicsek's model.Such a neighbor rule has been validated by biologists through experiments and the authors will prove that,similar to the Vicsek's model,such a new neighbor rule can also achieve consensus under some conditions imposed only on the system's speed and the number M,n,without resorting to any priori connectivity assumptions on the trajectory of the system.In particular,the authors will prove that if the number M is proportional to the population size n,then for any speed v,the system will achieve consensus with large probability if the population size is large enough. 展开更多
关键词 CONSENSUS multi-agent systems M-nearest neighbor random geometric graph topological distance.
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Regularity of the Koch-Tataru solutions to Navier-Stokes system Dedicated to the NSFC-CNRS Chinese-French summer institute on fluid mechanics in 2010 被引量:2
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作者 ZHANG Ping ZHANG Ting 《Science China Mathematics》 SCIE 2012年第1期453-464,共12页
In this paper, we shall prove that the Koch-Tataru solution u to the incompressible Navier-Stokes equations in Rd satisfies the decay estimates involving some borderline Besov norms with d ≥ 3. Moreover, u has a uniq... In this paper, we shall prove that the Koch-Tataru solution u to the incompressible Navier-Stokes equations in Rd satisfies the decay estimates involving some borderline Besov norms with d ≥ 3. Moreover, u has a unique trajectory which is HSlder continuous with respect to the space variables. 展开更多
关键词 Navier-Stokes equations Littlewood-Paley theory trajectories
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Gradients in predation risk in a tropical river system 被引量:4
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作者 Amy E. DEACON Faith A. M. JONES Anne E. MAGURRAN 《Current Zoology》 SCIE CAS CSCD 2018年第2期213-221,共9页
The importance of predation risk as a key driver of evolutionary change is exemplified by the Northern Range in Trinidad, where research on guppies living in multiple parallel streams has pro- vided invaluable insight... The importance of predation risk as a key driver of evolutionary change is exemplified by the Northern Range in Trinidad, where research on guppies living in multiple parallel streams has pro- vided invaluable insights into the process of evolution by natural selection. Although Trinidadian guppies are now a textbook example of evolution in action, studies have generally categorized predation as a dichotomous variable, representing high or low risk. Yet, ecologists appreciate that community structure and the attendant predation risk vary substantially over space and time. Here, we use data from a longitudinal study of fish assemblages at 16 different sites in the Northern Range to quantify temporal and spatial variation in predation risk. Specifically we ask: 1) Is there evidence for a gradient in predation risk? 2) Does the ranking of sites (by risk) change with the defi- nition of the predator community (in terms of species composition and abundance currency), and 3) Are site rankings consistent over time? We find compelling evidence that sites lie along a contin- uum of risk. However, site rankings along this gradient depend on how predation is quantified in terms of the species considered to be predators and the abundance currency is used. Nonetheless, for a given categorization and currency, rankings are relatively consistent over time. Our study sug- gests that consideration of predation gradients will lead to a more nuanced understanding of the role of predation risk in behavioral and evolutionary ecology. It also emphasizes the need to justify and report the definition of predation risk being used. 展开更多
关键词 abundance currency gradients Poecilia reticulata predation risk TRINIDAD Trinidadian guppy.
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