Network Security

In recent years, networks have become a standard feature of most computing environments. In many organizations, microcomputers are connected to a local area network (LAN); the network may in turn be attached to a mainframe as well as to other LANS or to various external data bases. Management does not always understand how these systems interconnect and may not appreciate the risks of network penetration.     

并行概率规划综述*

自动规划是人工智能的重要分支。它针对特定领域的特定问题,生成一个由可应用动作构成的规划。经典规划中的动作效果是确定的,且在每个时间步内只能执行一个动作。但在实际问题中,动作的效果往往是不确定性的,且动作的执行具有并发性。因此,并行概率规划(Parallel and Probabilistic Planning, PPP) 被提出,并在近两次国际规划比赛中有了专门的PPP比赛。PPP的应用前景正在引起规划研究学术圈的关注。有鉴于此,本文对其进行综述。具体内容包括定义PPP领域、问题和规划解,介绍其描述语言、基准领域及规划器,并对其中两个有代表性的规划器进行实际测试。实验表明在求解效率方面测试结果与比赛结果基本一致,但部分规划器的求解规模与竞赛不完全一致。这可能是比赛中的某些未开源代码或手工干预得到的。     

Assessing the impact of integrating business planning and IS planning

One of the key elements of strategic planning for information systems (IS) is the integration of IS planning (ISP) and business planning (BP). Although this issue has received significant attention in recent years, empirical research focusing specifically on it is still relatively sparse. Here, BP-ISP integration is considered in four ways (administrative, sequential, reciprocal, and full integration), reflecting various degrees of BP-ISP integration. The relationships between these and organizational impact (measured in terms of the extent of ISP problems and the extent of IS contributions to organizational performance) are investigated through the analysis of data gathered in a “matched pair” field survey of business planners and IS executives. The results empirically validate the importance of BP-ISP integration, since it was found to have a significant positive relationship with IS contributions to organization performance and a significant negative relationship to the extent of ISP problems.     

浅析办公室局域网的规划和部署

为更加有效的提高信息网络的管理水平,完善操作环境和优化操作流程,规划和部署办公室局域网络显得尤为重要。结合办公室局域网使用现状和用户使用需求,我们对局域网进行初步规划和网络部署。现将有关经验写出与大家进行交流。     

VLAN技术在校园网中的应用

虚拟局域网（VLAN）技术是目前网络技术中的一项重要技术。文章主要介绍了VLAN技术原理、优点及其划分,阐述了VLAN技术在管理维护校园网系统中所起的作用以及在校园网中用交换机配置VLAN的步骤,解决了校园网中存在的广播风暴和安全性问题。     

A knowledge-based system for developing retail location strategies

This paper proposes a knowledge-based system to support the analysis of problems and formulation of actions in the field of retail location planning. The decision table is used as a formalism for representing an exhaustive and exclusive set of decision rules typically used by Dutch planners and retailers. The proposed model is implemented in a knowledge-based system where it can be used interactively in combination with conventional spatial models for predicting and analysing retail system operations. A case study in the area of daily good facilities demonstrates the approach. The major conclusion is that the knowledge-based approach and in particular the decision table technique may assist planners/retailers to effectively structure complex retail location problems.     

On the predictability of domain‐independent temporal planners

Temporal planning is a research discipline that addresses the problem of generating a totally or a partially ordered sequence of actions that transform the environment from some initial state to a desired goal state, while taking into account time constraints and actions' duration. For its ability to describe and address temporal constraints, temporal planning is of critical importance for a wide range of real‐world applications. Predicting the performance of temporal planners can lead to significant improvements in the area, as planners can then be combined in order to boost the performance on a given set of problem instances. This paper investigates the predictability of the state‐of‐the‐art temporal planners by introducing a new set of temporal‐specific features and exploiting them for generating classification and regression empirical performance models (EPMs) of considered planners. EPMs are also tested with regard to their ability to select the most promising planner for efficiently solving a given temporal planning problem. Our extensive empirical analysis indicates that the introduced set of features allows to generate EPMs that can effectively perform algorithm selection, and the use of EPMs is therefore a promising direction for improving the state of the art of temporal planning, hence fostering the use of planning in real‐world applications.     

The first learning track of the international planning competition

The International Planning Competition is a biennial event organized in the context of the International Conference on Automated Planning and Scheduling. The 2008 competition included, for the first time, a learning track for comparing approaches for improving automated planners via learning. In this paper, we describe the structure of the learning track, the planning domains used for evaluation, the participating systems, the results, and our observations. Towards supporting the goal of domain-independent learning, one of the key features of the competition was to disallow any code changes or parameter tweaks after the training domains were revealed to the participants. The competition results show that at this stage no learning for planning system outperforms state-of-the-art planners in a domain independent manner across a wide range of domains. However, they appear to be close to providing such performance. Evaluating learning for planning systems in a blind competition raises important questions concerning criteria that should be taken into account in future competitions.     

Managing process diversity while improving your practices

In recent years, the software industry has gradually moved toward implementing standard processes across large organizations. The benefits of doing so include simplified accounting, measuring, and managing. Implementing organization-wide processes also makes it easier to judge the capabilities of an organization as a whole, which is important in large scale software development where organizational structures can have a profound impact on success. The article describes a project in which localized software practice improvements led to process diversity. It describes certain problems that were encountered and resolved during the effort. It also presents some simple techniques that any project, small or large, can use for managing diversity. The techniques discusses in the article evolved in the course of one multiyear project. If you do not carefully plan and manage process diversity, it quickly becomes unmanageable. The author used to advocate process uniformity, warning against the management problems caused by diversity, but recent experiences have suggested more effective ways to address these problems. The article explores these alternative strategies, which include adopting a basic set of practices that are uniformly enforced across all development steps, using risk analysis as a technique for selecting targets for software process improvement, and planning for process diversity     

Introduction to planning, scheduling and constraint satisfaction

Planning, scheduling and constraint satisfaction are important areas in artificial intelligence (AI). Many real-world problems are known as AI planning and scheduling problems, where resources must be allocated so as to optimize overall performance objectives. Therefore, solving these problems requires an adequate mixture of planning, scheduling and resource allocation to competing goal activities over time in the presence of complex state-dependent constraints. Constraint satisfaction plays also an important role to solve real-life problems, so that integrated techniques that manage planning and scheduling with constraint satisfaction remains necessary. This special issue on Planning, Scheduling and Constraint Satisfaction compiles a selection of papers of CAEPIA’2007 workshop on Planning, Scheduling and Constraint Satisfaction and COPLAS’2007: CP/ICAPS 2007 Joint Workshop on Constraint Satisfaction Techniques for Planning and Scheduling Problems. This issue presents novel advances on planning, scheduling, constraint programming/constraint satisfaction problems (CSPs) and many other common areas that exist among them. On the whole, this issue mainly focus on managing complex problems where planning, scheduling, constraint satisfaction and search must be combined and/or interrelated, which entails an enormous potential for practical applications and future research. Furthermore, this issue also includes a complete survey about constraint satisfaction, planning, scheduling and integration among these areas.     

Deterministic planning in the fifth international planning competition: PDDL3 and experimental evaluation of the planners

The international planning competition (IPC) is an important driver for planning research. The general goals of the IPC include pushing the state of the art in planning technology by posing new scientific challenges, encouraging direct comparison of planning systems and techniques, developing and improving a common planning domain definition language, and designing new planning domains and problems for the research community. This paper focuses on the deterministic part of the fifth international planning competition (IPC5), presenting the language and benchmark domains that we developed for the competition, as well as a detailed experimental evaluation of the deterministic planners that entered IPC5, which helps to understand the state of the art in the field.We present an extension of pddl, called pddl3, allowing the user to express strong and soft constraints about the structure of the desired plans, as well as strong and soft problem goals. We discuss the expressive power of the new language focusing on the restricted version that was used in IPC5, for which we give some basic results about its compilability into pddl2. Moreover, we study the relative performance of the IPC5 planners in terms of solved problems, CPU time, and plan quality; we analyse their behaviour with respect to the winners of the previous competition; and we evaluate them in terms of their capability of dealing with soft goals and constraints, and of finding good quality plans in general. Overall, the results indicate significant progress in the field, but they also reveal that some important issues remain open and require further research, such as dealing with strong constraints and computing high quality plans in metric-time domains and domains involving soft goals or constraints.     

Planners and their cognitive maps: an analysis of domain representations using multi dimensional scaling

We expected planners working on the planning problems at a particular department for many years to have similar ideas about their work domain. However, we found the opposite when we analyzed the results of an extensive knowledge elicitation study we performed on 25 planners working in the rolling stock and rolling staff planning department of the Netherlands Railways (in Dutch: NS). The planners were asked to model their domain by means of card sorting and graph-positioning methods using domain-related objects and relations. When we applied multi dimensional scaling to the outcome of this study, we found large differences in the individual cognitive maps thus created. In this article, we describe the analyses and discuss our findings about planners’ cognitive maps. These maps may have implications for the organization of planning in general, for training of planners, and for software design.     

基于Spring_Cloud微服务构架的局域网智能管理系统设计

近年来,局域网内各种病毒和网络攻击层出不穷,局域网管理遇到越来越多的问题和困难,根据局域网内5个不同的网络场景和实际需求,本文设计了局域网智能管理系统,系统主要包括5大功能模块:局域网资产管理、局域网服务器监控、站点监控、局域网流量监控、恶意软件探测,通过对系统模块的分析,利用阿里巴巴Nacos与SpringCloud建立了基于SpringCloud的局域网智能管理系统构架,将局域网智能管理系统的5个功能模块拆分成更小的微服务,与SpringCloud系统构架微服务,共同建立共享的微服务集群,本文详解分析了系统构架的组成和功能,以及系统构架所用到的关键技术和主要工具。同时,通过采用Docker容器的方法,将微服务部署在容器内实现快速迁移,方便将具体微服务部署到不同的环境中。     

性能优越的高速局域网——FDDI

ＦＤＤＩ是光电技术与计算机网络技本结合的产物，它解决了网络系统在系统膨胀时造成数据传输的拥塞问题，大大提高了网络可靠性．在结构上，ＦＤＤＩ采用了双逆向环结构，提供了独特的容错手段；在标准上，ＦＤＤＩ比目前可用的其他标准的ＬＡＮ技术有更高的速度和灵活性．本文描述了有关ＦＤＤＩ的技术将性；从网络的扩展性、容量、互联性、性能价格比以及内部协议等方面将ＦＤＤＩ与其它ＬＡＮ进行了有益的比较分析；最后给出一个ＰＤＤＩ的应用实例．     

Motion planning algorithms for molecular simulations: A survey

Motion planning is a fundamental problem in robotics that has motivated research since more than three decades ago. A large variety of algorithms have been proposed to compute feasible motions of multi-body systems in constrained workspaces. In recent years, some of these algorithms have surpassed the frontiers of robotics, finding applications in other domains such as industrial manufacturing, computer animation and computational structural biology. This paper concerns the latter domain, providing a survey on motion planning algorithms applied to molecular modeling and simulation. Both the algorithmic and application sides are discussed, as well as the different issues to be taken into consideration when extending robot motion planning algorithms to deal with molecules. From an algorithmic perspective, the paper gives a general overview of the different extensions to sampling-based motion planners. From the point of view of applications, the survey deals with problems involving protein folding and conformational transitions, as well as protein–ligand interactions.     

代理服务器在Internet中的应用

该文首先论述了代理服务器的功能和特点以及它所能解决的问题,然后以WinGate2．1为例详细说明了代理服务器的安装和使用方法.实践证明,通过代理服务器将Internet和局域网连接起来,是管理中、小型局域网的一个简单而有效的方法.     

Robot Motion Planning: A Game-Theoretic Foundation

Analysis techniques and algorithms for basic path planning have become quite valuable in a variety of applications such as robotics, virtual prototyping, computer graphics, and computational biology. Yet, basic path planning represents a very restricted version of general motion planning problems often encountered in robotics. Many problems can involve complications such as sensing and model uncertainties, nonholonomy, dynamics, multiple robots and goals, optimality criteria, unpredictability, and nonstationarity, in addition to standard geometric workspace constraints. This paper proposes a unified, game-theoretic mathematical foundation upon which analysis and algorithms can be developed for this broader class of problems, and is inspired by the similar benefits that were obtained by using unified configuration-space concepts for basic path planning. By taking this approach, a general algorithm has been obtained for computing approximate optimal solutions to a broad class of motion planning problems, including those involving uncertainty in sensing and control, environment uncertainties, and the coordination of multiple robots. Received November 11, 1996; revised March 13, 1998.