移动社会网络中基于社区的消息机会传输策略

移动社会网络是一种由大量具有社会特征的节点组成的机会网络.已有的基于社区的路由算法大多选用社会性最优的节点参与转发,而没有考虑到社区分布对节点移动的影响,将这些算法直接用于移动社会网络中会导致网络资源消耗高、传输成功率低等问题.针对这些问题,提出一种基于社区的消息机会传输算法,在社区间根据节点到目标社区的传输概率选择社区间的最优传输路径,在社区内选择与目标节点相遇概率较高的节点完成社区内传输.仿真实验结果表明,在移动社会网络中,该算法与 Prophet,Spray and Wait 等经典算法相比,提高了消息传输成功率,降低了网络开销.     

服务接触中的不公平事件：从顾客的角度

This study was designed to answer several key questions regarding the service injustice customers perceived during the service delivery. Using the critical incident technique, the authors collected 195 unfair incidents from a variety of service organizations. The initial sorting of the incidents resulted in four major groups: information asymmetry, unfair procedure, inappropriate attitudes and manners of the service personnel, and unfair outcomes. Within the four major classifications of critical incidents, 13 secondary categories were identified. A further analysis was conducted to discover the underlying reason why customers feel unfair in the service encounters. Finally, some implications for service managers were discussed.     

王快水库与西大洋水库连通条件下入库径流演变及影响因素分析

研究王快水库与西大洋水库两库连通状态下的入库径流变化规律与丰枯遭遇,对于保障雄安新区用水安全有重要意义。基于1971～2015年共45年的径流和降水的月数据系列,利用滑动平均法、有序聚类法、不均匀系数、集中度、集中期和频率分析法等,研究了王快与西大洋水库入库径流的年际年内变化,并分析了两库的丰枯遭遇状况。结果表明,王快水库与西大洋水库年际入库径流总体呈减少趋势,随时间变化表现出丰枯交替现象,45年间均出现两次突变,突变时间为1979、1996年;入库径流年内分配不均匀性、集中程度均呈下降趋势,随着时间推移入库径流年内分配趋于均匀,两库入库径流的变化规律在年际、年内一致。不论是全年还是年内各月,王快水库与西大洋水库丰枯同步频率大于丰枯异步频率,丰枯同步性高,丰枯补偿特征不明显。入库径流的变化受降水及人类活动的综合作用影响。研究成果可为径流调控提供参考。     

Framework of emergence: from chain of value to value constellation

ABSTRACT

For academic design programmes and research councils, finding mechanisms to measure impact and valuate co-design research projects is very difficult. The metric parameters – number of attendees, volume, shape, length – have shown to be insufficient. The subject matter, the subjects and matters, do not easily fit within these parameters, which fail to translate the value of a ‘constellation of affections’ that emerge throughout co-design processes. Emphasis on quantifiable impact derives from particular ways of understanding production, reproduction, and dissemination of knowledge. This paper understands academic design programmes as a technology to discuss axiology in co-design practices. This paper re-configures a techno-logic of value; from chain of value to value constellation, intersecting a co-design case study with readings of Simondon’s philosophy of technology and Barad’s agential realism. Ageing Playfully was a knowledge exchange project from The Creative Exchange programme, that involved people living with dementia and their caregivers co-designing interventions to boost mobility and well-being. At the core, this paper, explores an axiological move that informs a framework of emergence, a way of thinking in methods to account for the value of co-design as site of emergence.     

Neighbourhood participation in super-diverse contexts: comparing Amsterdam and Vienna

Urban policies are increasingly localized, stressing the role of neighbourhood social contacts in generating cohesion and citizen participation. Studies on ‘everyday’ multiculturalism also emphasize the neighbourhood as a meaningful place for encounters. However, there remains a lack of understanding of how specific contexts condition encounters with difference. We compare two European neighbourhoods that provide different contexts for participation: Amsterdam and Vienna. We ask how residents experience local spaces of encounter and how this influences their experience of the neighbourhood. We find a mismatch between the aims of local policies and the experiences of residents, who also value more superficial contacts.     

弹目交会参数对超宽带近炸引信设计的约束分析

UWB(超宽带)近炸引信是一种新体制近炸引信,现有文献对系统的分析设计主要是针对器件的设计,有关引信战术指标的优化设计还是空白.在阐明了UWB(超宽带)近炸引信的测距原理和作用过程的基础上,首次通过对某种弹目交会条件的分析,在一假定的初始条件下,进行了数值仿真分析,得出系统探测距离与天线的波束倾角之间的关系,为系统整体设计优化指出了方向,对系统的具体战术指标确定提供了理论依据.     

作战仿真中飞机避碰智能决策研究

在作战仿真建模的过程中,不仅包括三维战场的建模,还包括飞机等对象的动力学模型。分析了在仿真环境下影响空战中飞机发生碰撞危险的各种因素,重点对相遇飞机避碰决策进行研究,最后提出了相应的解决问题的方案,并给出了工作流程图。     

Lightweight opportunistic routing forwarding strategy based on Markov chain

A lightweight opportunistic routing forwarding strategy (MOR) was proposed based on Markov chain.In the scheme,the execute process of network was divided into a plurality of equal time period,and the random encounter state of node in each time period was represented by activity degree.The state sequence of a plurality of continuous time period constitutes a discrete Markov chain.The activity degree of encounter node was estimated by Markov model to predict its state of future time period,which can enhance the accuracy of activity degree estimation.Then,the method of comprehensive evaluating forwarding utility was designed based on the activity degree of node and the average encounter interval.MOR used the utility of node for making a routing forwarding decision.Each node only maintained a state of last time period and a state transition probability matrix,and a vector recording the average encounter interval of nodes.So,the routing forwarding decision algorithm was simple and efficient,low time and space complexity.Furthermore,the method was proposed to set optimal number of the message copy based on multiple factors,which can effectively balance the utilization of network resources.Results show that compared with existing algorithms,MOR algorithm can effectively increase the delivery ratio and reduce the delivery delay,and lower routing overhead ratio.     

长江上游干支流洪水组成与遭遇研究

通过对长江上游洪水组成及遭遇规律的研究,可为长江中游干流控制性枢纽制定调度方案提供理论基础。根据各代表站实测资料(包括年最大洪水及发生时间),考虑洪水传播时间,逐年分析金沙江与岷江、长江与嘉陵江、长江与乌江的洪水遭遇可能性,然后分析遭遇概率的高低和遭遇洪水量级。研究成果表明,长江与岷江、嘉陵江洪水遭遇概率较高,除个别年份外,一般遭遇洪水量级较小;长江与乌江洪水遭遇概率较低,且遭遇洪水一般为中小洪水;长江上游干支流同时发生较大洪水遭遇的机率很小。     

黄河河口镇至龙门区间洪水特性分析

通过对黄河河口镇至龙门区间近 40年的实测水文资料 ,对黄河龙门水文站发生的 Q>60 0 0 m3 /s的 75场次洪水 (按照不同流量级别 )进行了统计分析。得出了河龙区间 Q>60 0 0 m3 /s的洪水来源、基本组成 ,年内分配以及区间内不同区段洪水的遭遇等基本特性。研究河龙区间洪水的基本特性 ,对于提高该区间洪水测验精度和黄河下游的防汛有着重要的意义