局域网服务器缓冲区容量的Petri网设计方法

本文在分析局域网服务器信息缓冲区、数据包接受和发送缓冲区的相互关系基础上提出一种新的局域网服务器缓冲区设计方法─—广义随机Ｐｅｔｒｉ网方法，并给出了局域网服务器信息缓冲区的广义随机Ｐｅｔｒｉ网模型。该设计方法理论完备、严谨实用，且不再局限于追求某一边界值（上限或下限），并且避免了排队理论处理多级服务的繁琐公式。最后本文用一例题说明了这种方法的应用。     

The Appropriation of the Material of Places in the Landscape: the case of tufa and springs

Springs have long been recognized as being significant places in the landscape, and there is ample evidence of later-prehistoric and Roman activity at spring sites. The Christian appropriation of springs as 'places', either indirectly by assigning their origin to saints, or directly by building chapels and churches on spring-head sites, is also well evidenced. The possibility that the material of petrifying springs - tufa - was both transplanted and appropriated, and that the symbolic properties of the material may go back well into British prehistory, is explored.     

一种排课问题的形式化描述体系和框架

排课问题主要解决时间和空间资源冲突,以优化教学资源和教学时间的分配,实现教学资源的负载均衡.提出一种新的排课约束的表述框架--时间地点限定表达式,可以通过形式推理缩减排课问题空间,支持基于案例和规则的排课问题求解.     

Fault detection for discrete event systems using Petri nets with unobservable transitions

In this paper we present a fault detection approach for discrete event systems using Petri nets. We assume that some of the transitions of the net are unobservable, including all those transitions that model faulty behaviors. Our diagnosis approach is based on the notions of basis marking and justification, that allow us to characterize the set of markings that are consistent with the actual observation, and the set of unobservable transitions whose firing enable it. This approach applies to all net systems whose unobservable subnet is acyclic. If the net system is also bounded the proposed approach may be significantly simplified by moving the most burdensome part of the procedure off-line, thanks to the construction of a graph, called the basis reachability graph.     

PIRF-Nav 2.0: Fast and online incremental appearance-based loop-closure detection in an indoor environment

This paper presents a fast and online incremental solution for an appearance-based loop-closure detection problem in a dynamic indoor environment. Closing the loop in a dynamic environment has been an important topic in robotics for decades. Recently, PIRF-Nav has been reported as being successful in achieving high recall rate at precision 1. However, PIRF-Nav has three main disadvantages: (i) the computational expense of PIRF-Nav is beyond real-time, (ii) it utilizes a large amount of memory in the redundant process of keeping signatures of places, and (iii) it is ill-suited to an indoor environment. These factors hinder the use of PIRF-Nav in a general environment for long-term, high-speed mobile robotic applications. Therefore, this paper proposes two techniques: (i) new modified PIRF extraction that makes the system more suitable for an indoor environment and (ii) new dictionary management that can eliminate redundant searching and conserve memory consumption. The results show that our proposed method can complete tasks up to 12 times faster than PIRF-Nav with only a slight percentage decline in recall. In addition, we collected additional data from a university canteen crowded during lunch time. Even in this crowded indoor environment, our proposed method has better real-time processing performance compared with other methods.     

国际高档男装A品牌进入上海市场的营销策略研究

本文以国际高档服装品牌A进入上海市场为例进行典型分析,具体分析国际服装品牌A在进入上海 男装市场的市场营销策略,也希望对其它的服装品牌进入上海市场时能够有所帮助。     

Residents' attitudes to proposed wind farms in the West Coast region of South Africa: A social perspective from the South

The West Coast Region (WCR) of the Western Cape Province in South Africa is earmarked for 13 onshore wind farm projects totaling approximately 700 wind turbines. The developed world debate about the social acceptance of wind farm projects has impeded and illuminated a number of these developments. This paper is aimed at understanding people's reaction to proposed wind farm projects in the WCR – a region of a developing country – and to investigate whether the reasoning behind opposition to or acceptance of wind farm projects is similar to the discourse on the topic by scholars in the developed world. Quantitative and qualitative methods were used to collect primary data by semi-structured interviews and a questionnaire survey. A spatial dimension was added through a map-based approach. Reactions by WCR residents to the wind farm projects were mainly positive, although some opposition was detected. International scholarship holds that place attachment serves as a reason for opposition to wind farm projects. Although most of the WCR residents had strong place attachments to their region, most of the respondents also supported the proposed wind farm projects.     

Augmented places: An impact of embodied historical experience on attitudes towards places

AimThe purpose of this paper was to examine the possibility of using Augmented Reality to reduce memory-related ethnic bias towards places and to increase understanding of multicultural place meaning and change emotional attitudes towards historical sites.BackgroundTheoretical and empirical works suggest that the direct, embodied contact with place's history facilitates understanding of its past. Places which were deprived of historical continuity are less liked and threatened by ethnic bias in collective memory. AR technology gives a possibility of recreating past of such places and in a consequence tests an influence of experience of place's history on psychological aspects of the people-place relationship.MethodA between-subjects experiment was conducted, in which participants either walked with an AR application displaying historical photos in real environment or watched photos on computers. The chosen place was the former Jewish district in Warsaw, Poland.ResultsThe results of multiple regression analyses showed that the AR application can facilitate positive attitudes towards a place, reduce ethnic bias and enhance multicultural place meaning.ConclusionsWe argue that AR could be used as a method of reviving (multi)cultural heritage, but also as a tool of reducing prejudices and increasing openness to other cultures and traditions.