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131.
During 1999-2001 the building research establishment (BRE) undertook a measurement based survey of environmental noise levels and a social survey of population attitudes to environmental noise in the UK. The surveys involved a total of 1160 24-h noise measurements at a sample of dwellings in the UK, and over 5500 in-depth interviews with a sample of the UK adult population. Both samples were of a clustered random design, and were representative of the UK population. The results of the surveys have been compared with those from similar surveys undertaken by BRE in 1990/1991 and are currently being used to help formulate a more strategic approach to the control of environmental noise both nationally and in London.  相似文献   
132.
We study an elementary two-player card game where in each round players compare cards and the holder of the card with the smaller value wins. Using the rate equations approach, we treat the stochastic version of the game in which cards are drawn randomly. We obtain an exact solution for arbitrary initial conditions. In general, the game approaches a steady state where the card value densities of the two players are proportional to each other. The leading small value behavior of the initial densities determines the corresponding proportionality constant, while the next correction governs the asymptotic time dependence. The relaxation toward the steady state exhibits a rich behavior, e.g., it may be algebraically slow or exponentially fast. Moreover, in ruin situations where one player eventually wins all cards, the game may even end in a finite time. Received 24 August 2001 and Received in final form 12 November 2001  相似文献   
133.
The objective of this study was to compare the psychometric properties of voice disordered quality of life (VQOL) instruments. Nine VQOL instruments were identified through a comprehensive literature search. Based on specific criteria, four were selected for comprehensive review: Voice Handicap Index (VHI), Voice Activity and Participation Profile (VAPP), Voice-Related Quality of Life (V-RQOL) and Voice Outcome Survey (VOS). Selected instruments were evaluated based on 11 measurement standards related to item information, versatility, practicality, breadth and depth of health measure, reliability, validity, and responsiveness. VHI and V-RQOL each met 7 of 11 criteria, with VHI showing additional preferable item information, practicality, and reliability over V-RQOL and V-RQOL showing preferable responsiveness properties over VHI. These study results do not support the Social Security Administration's recent conclusion that the VHI meets reliability and validity standards for individual decision making. Nevertheless, the present results do support the use of VHI total scores for clinical use with individual patients, and the use of V-RQOL total scores or individual dimension scores for use with groups of patients.  相似文献   
134.
The following is a brief English summary of the paper Mirkin (1979), in which he discusses social welfare functions where the relations involved are solely assumed to be reflexive. Under axioms of independence and neutrality, monotonicity, and two domain assumptions the author shows that such a social welfare function is determined by a ‘federation’,i.e., the set of coalitions such that if that each member considers a not worse than b so does the group. The author then characterizes transitive, completeness, definiteness, (a sort of non-indifference assumption), and majority rule in this framework. He also characterizes those domains on which social welfare functions determined by federations F satisfying IF if and only if ī ? F, are transitive. We omit proofs, which are given in the Russian version, as well as the author's discussion of these results.  相似文献   
135.
An n-person social choice problem is considered in which the alternatives are n dimensional vectors, with the ith component of such a vector being the part of the alternatives affecting individual i alone. Assuming that individuals are selfish (individual i must be indifferent between any two alternatives with the same components), that they may be indifferent among alternatives and that each individual may choose his preferences out of a different set of permissible preferences, we prove that any set of restricted domains of preferences admits an n person non-dictatorial Arrow-type social welfare function if and only if it admits a two-person Arrow-type social welfare function: we characterize all the sets of restricted domains of preferences which admit two-person Arrow-type social welfare functions (and therefore also admit n-person Arrow-type social welfare functions) and then we prove that we also characterized all the sets of restricted domains of preferences which admit nondictatorial, nonmanipulable, noncorruptible and rational social choice correspondences.  相似文献   
136.
随着网络应用的广泛普及,QQ、微信、YY语音、陌陌等社交软件走进千家万户,但社交网络用户浏览轨迹信息隐私保护问题也随之而来。由于社交网络平台安全机制存在漏洞,抵御网络攻击性能不强,使社交网络用户信息纷纷泄露。针对问题根源,提出ACP用户隐私信息防护系统,建立社交网络用户真空登陆模块(VM)、通讯信息密码文模块(RDT)及信息储存保护墙模块(LDM)一体化ACP用户隐私信息防护系统,从根源保护社交网络用户浏览轨迹信息的隐私安全。通过数据模拟仿真实验证明提出的ACP用户隐私信息防护系统,对社交网络用户浏览轨迹信息隐私保护具有可用性与有效性。  相似文献   
137.
An evolutionary prisoner's dilemma game (PDG) with players located on Barabási–Albert scale-free networks (BASFN) with average connectivity 88 is studied in detail. The players are pure strategists and can adopt two strategies: either defect or cooperate. Several alternative update rules determining the evolution of each player's strategy are considered. Using Monte Carlo (MC) simulations we implemented both synchronous and asynchronous update dynamics to calculate the average density of cooperators ρCρC as a function of the temptation-to-defect bb in the equilibrium state. For the sake of comparison, evolution of cooperative behavior on random regular graphs (RRG) and regular lattices (RL) with the same total size and average connectivity as BASFN are also investigated. We find the overall result that cooperation is sometimes inhibited and sometimes enhanced on the BASFN, with respect to the cases on the RRG and RL. The differences depend on the detailed evaluation function of the players’ success (average payoffs of the players in the present case), the different update rules that determine a player's future strategy, the synchronous and asynchronous events of strategy-updating, and also on the temptation to defect.  相似文献   
138.
In this paper, we analyze the effects of levels of social relationship on a multiperiod supply chain network with multiple decision-makers (suppliers, manufacturers, and retailers) associated at different tiers. The model incorporates the individual attitudes towards disruption and opportunism risks and allows us to investigate the interplay of the heterogeneous decision-makers and to compute the resultant network equilibrium pattern of production, transactions, prices, and levels of social relationship over the multiperiod planning horizon. In our analysis, we focus on the following questions: (1) how do the evolving relationships affect the profitability and risks of supply chain firms as well as the prices and demands of the product in the market? (2) how do the relationships with the upstream supply chain firms affect the relationships with the downstream firms, and how these relationships influence the profitability and risks of the supply chain firms? (3) how do the supply disruption risks interact with the opportunism risks through supply chain relationships, and how these risks influence the profitability of the firms? The results show that high levels of relationship can lead to lower supply chain overall cost, lower risk, lower prices, higher product transaction and therefore higher profit.  相似文献   
139.
M.J. Krawczyk 《Physica A》2011,390(13):2611-2618
It was demonstrated recently that the line graphs are clustered and assortative. These topological features are known to characterize some social networks [M.E.J. Newman, Y. Park, Why social networks are different from other types of networks, Phys. Rev. E 68 (2003) 036122]; it was argued that this similarity reveals their cliquey character. In the model proposed here, a social network is the line graph of an initial network of families, communities, interest groups, school classes and small companies. These groups play the role of nodes, and individuals are represented by links between these nodes. The picture is supported by the data on the LiveJournal network of about 8×106 people.  相似文献   
140.
F. Bagarello 《Physica A》2011,390(15):2803-2811
In a series of recent papers we have used an operatorial technique to describe stock markets and, in a different context, love affairs and their time evolutions. The strategy proposed so far does not allow any dumping effect. In this short note we show how, within the same framework, a strictly non-periodic or quasi-periodic effect can be introduced in the model by describing in some details a linear Alice-Bob love relation with damping.  相似文献   
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