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21.
This research project proposes the modeling of collective behaviors such as flocks, industrial districts, and markets. Unlike many other approaches, the aim is to identify ways to recognize, change, and maintain the coherence of collective behaviors, as well as inducing their emergence in configurations of elements that only interact without acquiring properties. The basic assumption is that currently collective behavior is not adequately modeled for the purpose described above when intended as given by sequences of states adopted by the same system over time. Here the sequence of states of a collective behavior in time is considered as corresponding to sequences of different states adopted by systems made up of the same elements interacting with different structures. Sequences of structures are considered to establish meta-structures and their properties correspond to the coherence acquired. The project is based on the use of mesoscopic variables to represent such structural dynamics considered in turn to represent the continuous emergence of coherent collective behavior. Mesoscopic variables are specified and their properties considered as meta-structural properties (properties of sequences of structures). The purpose of this research project is to search for meta-structural properties within processes of computational emergence (computer simulated). I discuss the problem of prescribing meta-structural properties to non-coherent, disordered collective behaviors. I introduce possible approaches for applications to social systems.  相似文献   
22.
The primary aim of this equivalence study was to compare the outcome of a brief group therapeutic intervention, based on the principles of dynamic interpersonal therapy (DIT) with an intervention based on cognitive behavioural therapy (CBT) in patients suffering from medically unexplained somatic symptoms (MUSS). Participants were 89 patients (aged 18 to 62) who were offered 20 sessions of either DIT or CBT, as central part of a treatment package, consisting of art therapy, psychomotor therapy, social therapy and physical therapy. Measurements were conducted at baseline, 10 weeks and 20 weeks, using self-rating scales measuring the level of anxiety and depression, the severity of medically unexplained symptoms and quality of life. Results showed that CBT and DIT were comparable. The conclusion was that it is recommended to design a larger scale randomised controlled trial to further elaborate the short-term and long-term effects of this novel psychodynamic group therapy for MUSS patients.  相似文献   
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This article describes a design strategy deployed in developing ultra-ductile Mg alloys based on a microalloying concept, which aims to restrict grain growth considerably during alloy casting and forming. We discuss the efficiency of the design approach, and evaluate the resulting microstructural and mechanical properties. After processing, the so-designed alloys ZQCa3 (Mg–3Zn–0.5Ag–0.25Ca–0.15Mn, in wt.%) and ZKQCa3 (Mg–3Zn–0.5Zr–0.5Ag–0.25Ca–0.15Mn, in wt.%) reveal very fine grains (<10 µm), high ductility (elongation to fracture of up to 30%) at moderate strength or high strength (ultimate tensile strength of up to 350 MPa) at reasonable ductility. These properties are explained based on thermodynamic modelling, microstructure analysis including transmission electron microscopy studies, and microstructural and mechanical testing after annealing, and are compared to a related commercial alloy (ZK31).  相似文献   
25.
The crystal growth velocity of Ni95Si5 and Ni90Si10 alloys as a function of undercooling is investigated using molecular dynamics simulations. The modified imbedded atom method potential yields the equilibrium liquidus temperatures T L?≈?1505 and 1387?K for Ni95Si5 and Ni90Si10 alloys, respectively. From the liquidus temperatures down to the deeply undercooled region, the crystal growth velocities of both the alloys rise to the maximum with increasing undercooling and then drop slowly, whereas the athermal growth process presented in elemental Ni is not observed in Ni–Si alloys. Instead, the undercooling dependence of the growth velocity can be well-described by the diffusion-limited model, furthermore, the activation energy associated with the diffusion from melt to interface increases as the concentration increases from 5 to 10?at.% Si, resulting in the remarkable decrease of growth velocity.  相似文献   
26.
视觉词汇加工的动态神经网络及其形成   总被引:1,自引:0,他引:1  
揭示大脑加工的神经网络机制成为认知神经科学研究的最新取向.本研究以视觉词汇加工脑区(VWFA)的神经功能作为切入点,探讨视觉词汇加工神经网络的动态机制及其形成.研究一考察VWFA在刺激驱动和任务调节下的动态激活,及其与语音、语义脑区所组成神经网络的动态机制.研究二通过跨文化对比以及儿童阅读发展研究,阐明语言经验对视觉词汇加工网络的塑造作用.研究三对比功能网络、静息网络以及白质纤维束联结,探讨视觉词汇加工网络的动态联结及其形成.研究结果有助于建构视觉词汇加工的神经生理模型,为基于脑科学的阅读教学和阅读障碍矫治奠定理论基础,为认知神经科学研究提供了新的思路.  相似文献   
27.
高飞  蔡厚德 《心理科学进展》2013,21(7):1200-1212
胼胝体是哺乳动物脑内最大的白质结构,不仅可以在大脑两半球间传递信息,也能调节半球间的相互作用,“抑制模型”和“兴奋模型”是当前解释胼胝体调节机制的主要模型.前者假设,胼胝体对半球间的信息传递起抑制作用,表现为优势半球的功能增强,非优势半球的活动抑制,因而可以提高半球加工的独立性和功能不对称性;后者则认为,胼胝体对半球间信息传递起促进作用,导致两半球同时性活动,并增强其功能连接性,因而可以降低半球的功能不对称性,有利于半球间的信息共享与功能整合.近期的研究显示,胼胝体并不是一个结构与功能的单一体,而是包含了在空间与时间上既分离又互动的多通道信息加工复合体.抑制与兴奋信息可以通过胼胝体的不同空间通道以不同的速度在半球间进行传递,并受到任务计算类型与复杂性的调节,因此,胼胝体的抑制与兴奋的协同可以调节两半球的动态相互作用.  相似文献   
28.
A new psycho-social system approach to well-being is presented, in which psychological and social functioning is understood through an empirically derived framework of five domains. A quantitative co-term analysis was performed on 3466 terms within 18,401 PsycINFO® journal documents on topics related to positive psychology (PP) across disciplines such as psychology, education, management, business and psychiatry. The analysis revealed that research on PP topics can be classified into five broad domains: attention and awareness, comprehension and coping, emotions, goals and habits, and virtues and relationships. These domains provide a new systematic framework, the Five Domains of Positive Functioning, for understanding positive psycho-social functioning and exploring the underlying ways in which people function to achieve well-being outcomes. When used within the psycho-social system approach, the framework can be used in future research to clarify mechanisms of change, facilitate comparisons between different PP interventions and suggest ways to improve intervention effectiveness.  相似文献   
29.
This paper argues that the EuropeanCourt of Human Rights couldserve as a model for an international court ofhuman rights to be builtupon the United Nations Committee on HumanRights. It argues that theconcerns states might have over the surrenderof a significant portion oftheir national sovereignity might be lessenedif such an internationalcourt were to incorporate the margin ofappreciation doctrine employed bythe European Court of Human Rights. Thisdoctrine is intended to respectthe customs and traditions of sovereign statesin dealing with humanrights issues, while maintaining that somerights such as the right not tobe tortured will be considered as basic andwill stand independently ofthe customs and traditions of sovereignstates.  相似文献   
30.
Logic Games are Complete for Game Logics   总被引:1,自引:0,他引:1  
van Benthem  Johan 《Studia Logica》2003,75(2):183-203
Game logics describe general games through powers of players for forcing outcomes. In particular, they encode an algebra of sequential game operations such as choice, dual and composition. Logic games are special games for specific purposes such as proof or semantical evaluation for first-order or modal languages. We show that the general algebra of game operations coincides with that over just logical evaluation games, whence the latter are quite general after all. The main tool in proving this is a representation of arbitrary games as modal or first-order evaluation games. We probe how far our analysis extends to product operations on games. We also discuss some more general consequences of this new perspective for standard logic.  相似文献   
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