基于定位辅助按需拓扑维护的超宽带自组网路由算法

提出了一种基于定位辅助按需拓扑维护的超宽带自组网路由算法,该算法利用超宽带技术精确定位信息所获得的网络拓扑信息和路由信息进行分组转发,路由维护阶段在定位信息辅助下采用按需方式进行断链路由的修复和拓扑维护,通过基于位置信息的按需路由发现和限制路由查找范围,以及定位信息和网络拓扑信息的及时更新,在降低协议开销的同时保证了算法的有效性。仿真表明,该算法在分组丢失率、平均端到端时延和路由附加开销等方面具有良好性能,其优良的分布式控制特征能适应超宽带自组网的动态环境。     

基于贝叶斯神经网络的非参数回归

提高神经网络模型推广能力的关键是控制模型的复杂度。该文探索了贝叶斯神经网络的非参数回归的建模方法,通过融入模型参数的先验知识,在给定数据样本及模型假设下进行后验概率的贝叶斯推理,使用马尔可夫链蒙特卡罗算法来优化模型控制参数,实现了对神经网络模型中不同部分复杂度的控制,获得了模型参数的后验分布及预测分布。在5个含噪二维函数回归问题上的应用显示了模型的复杂度能根据数据的复杂度而自适应调整,并给出了较好的预测结果。     

First Housing Moves in Spain: An Analysis of Leaving Home and First Housing Acquisition

This paper examines young people's firsthousing acquisition in Spain. The majority ofyoung Spanish people leave home to buy aproperty and to live with a partner and/orchild. We examine the extent to which thistransition dominates first housing moves duringthe 1980s and consider the ways in which widerfamily networks facilitate leaving home to buya property. We then examine characteristicsassociated with deviation from this normativeroute. We find alternative transitions,particularly moving into rented accommodation,are more common among young people from moreadvantaged backgrounds, and those living innorthern Spain.     

‘The Effect of Social Networks at Origin Communities on Migrant Remittances: Evidence from Nang Rong District’

The literature on the effect of social networks on migrant remittances has ignored the influence of a household’s embeddedness in social networks in the origin community. This paper, using multilevel statistical modeling and social survey data from Nang Rong district in Thailand, examines how remittances between migrants and origin households are associated with social networks. Social network measures come from data on sibling and rice harvest network ties. Rice harvesting is very important to the rural economy, and households participating in the network are privy to vital sources of news and information that spread through the network. Results support the notion that migrants remit less to households that are isolates in the rice-harvesting network, which is theorized to be associated with access to information about employment options.     

Identifying regular blocks in valued networks: A heuristic applied to the St. Marks carbon flow data,and international trade in cereal products

While the concept of regular equivalence is equally applicable to dichotomous as well as valued networks, the identification of regular blocks in regular blockmodels is somewhat problematic when dealing with valued networks. Applying the standard procedure for identifying ties in such blockmodels, a procedure perhaps most suited for dichotomous networks, does tend to generate block images and reduced graphs that differ from intuitive notions of such structures.     

关于移动自组网自安全证书管理模型

对目前建立移动自组网信任模型的各种主流方案进行了分类和评述,重点阐述了自安全证书管理模型各种方案的优缺点,并指出了今后的研究方向.     

发展用户驻地网与打破本地固话垄断

本文提出了一个发展用户驻地网的思路,着重论述了发展用户驻地网可有效地打破本地固话垄断,兼述了发展驻地网对电信管制的影响及发展驻地网所需解决的问题。     

Bayesian inference for a discretely observed stochastic kinetic model

The ability to infer parameters of gene regulatory networks is emerging as a key problem in systems biology. The biochemical data are intrinsically stochastic and tend to be observed by means of discrete-time sampling systems, which are often limited in their completeness. In this paper we explore how to make Bayesian inference for the kinetic rate constants of regulatory networks, using the stochastic kinetic Lotka-Volterra system as a model. This simple model describes behaviour typical of many biochemical networks which exhibit auto-regulatory behaviour. Various MCMC algorithms are described and their performance evaluated in several data-poor scenarios. An algorithm based on an approximating process is shown to be particularly efficient.     

Risk,trust and knowledge networks in farmers’ learning

This study reports on New Zealand dairy farmers’ access to and use of information as mediated through conditions of risk and trust within the context of their interpersonal social networks. We located participants’ reports of their information use within their perceived environments of trust and risk, following Giddens's [1990. The consequences of modernity. Polity Press, Stanford, CA] typology of trust and risk in pre-modernity and modernity. The research participants were constant users of interpersonal and print information from numerous sources, and monitored their incoming data in the light of strategic needs, reflecting their roles as both farming practitioners and business owners. Socio-spatial knowledge networks (SSKNs) combine individuals’ explanatory cognitive models of information acquisition and use with a micro-geographical analysis of their interpersonal networks. The participants showed characteristics of pre-modern, modern and even post-modern society in respect of their use of complex interactional forms, as well as a blending of individualistic and communitarian practices and concerns in their professional and personal lives.     

平板非稳态导热逆问题的近似解

对一维物体非稳态加热或冷却的表面温度的计算进行了研究，在增加一个参数的基础上，采用积分求解的方法，获得了一个近似解，此解不仅表达式简单，便于应用，而且具有较高的准确度，该表达式还可方便地应用于变异热系数的场合。