一种用于Java消息中间件的自适应框架

消息中间件的性能与系统资源的消耗之间存在着一定的矛盾.一般采用人工配置的方法平衡矛盾,不仅难于配置,而且不能很好地适应系统的动态性.本文提出了一种基于模糊控制理论的自适应框架,可以在消息中间件的性能与其稳定性、可靠性之间作较好的平衡.本框架引入AOP的思想,可以与不同类型的消息中间件集成,具有一定的普适性.     

高效、高质量的纸质工程图和资料存档方案

一、传统保存方案的缺陷 传统的工程图样和资料的保存归档形式是通过纸质或胶片的形式进行的,很多企业都用专门的仓库保管这些珍贵的技术资料.这些资料的内容相当广泛,包括机械设计、建筑设计、工程设计、测绘及地图等各行业的信息.资料的介质也有不同的分类,包括硫酸纸、纸质蓝图、白图及胶片等.     

VoIP防火墙穿越方法的研究与比较

VoIP技术已经广泛应用于企业级的语音业务,但是为了安全性和节省IP地址的使用,目前大量的企业和局域网都采用Firewall/NAT技术连接到Internet.比较了传统的Firewall/NAT的穿越方案,并介绍和比较了较新的ICE和VPN穿越方式,描述了各种穿越方法的穿越机制,分析了各种方法的优缺点,并作了横向比较.     

在重庆建设机电产品可靠性与测试技术工程中心的必要性与可行性研究

提高产品的可靠性成为企业在今后相当长的时间内生存和发展的必要条件之一.推动可靠性技术的普及与应用必须有相关的专业队伍和机构,本文从五个方面阐述了建设机电产品可靠性与测试技术工程中心的必要性,结合重庆工业自动化仪表研究所的实际情况,从五个方面论述了建立工程中心的可行性.期望通过本文,能推动重庆市建立这样的机构,协助企业有效提高产品的可靠性水平,从而在市场竞争中占据有利的地位.     

DSP主机接口和PC机并行接口的接口电路的设计

描述了TI的C5000系列的DSP的主机接口(HPI)与PC机的并行接口(ECP模式PS/2子模式)进行连接的硬件设计方案,并提出在各种Windows操作系统下对接口进行操作的驱动软件的解决方法.该方案充分利用了DSP的HPI接口的特点,采用了少量的逻辑电路,实现了PC并行接口和DSP的主机接口的双向连接,使PC机能实时读写DSP任意片内存储单元的内容,控制DSP系统的运行.     

谷歌:让正版音乐自由飞翔

一曲美妙动听的音乐不仅能陶冶人们的情操,还可以缓解人们压抑的心情,使人们的身心得以放松。音乐不但可以敲开封闭的心灵,缓解忧郁苦闷的心情,甚至还可以做到某些程度的心灵治疗。而一首激情高昂的音乐,不但可以提高人们的凝聚力,还能激发人们奋发向上的精神。     

论网络时代医药企业的营销决策

传统的营销方式在网络时代已经不再占有优势,网络时代的营销也不仅仅是做个网站来展示自己的商品,而是通过人性化的服务来进一步推销自己的产品.传统意义上的市场营销,是指个人和群体通过创造并同他人交换产品和价值,以满足需求和欲望的一种社会和管理过程.     

一种基于XML的个性化的资源需求描述机制

在基于因特网的教育资源网格体系结构和服务理论研究中,提出了教育资源网格中一种基于XML的个性化文件资源需求描述机制.需求者不仅可以更加准确地表达自己对各类文件资源的需求,还可以指明自己所期望的资源的区域和学校的来源.并且对备选的信息进行优先级的排序,在搜索的过程中按照优先级的顺序对搜索的结果进行优化.解决了资源需求描述机制中对教育资源网格的文件资源需求描述支持较少的问题.     

新产品&工具

Internet Explorer 8 Beta 2随着Firefox 3的推出,微软的IE 8的研发工作也在紧锣密鼓的进行着。之前Beta 1版本在标准的支持和兼容性上有了很大的改进,而8月中旬放出的Bela 2除了在Web标准方面做了更多的改进,在功能方面又有了很大的提高。例如在结构上的调整使得IE更加稳定、对WebSlice的支持、自动恢复、Session Cookie等。此外,在性能方面也有很大的提高。     

维护国家安全 规制网络舆论

近期发生的家乐福、CNN 报道事件,引起了一连串的反应,先是网络上网民的激烈讨论,接着是媒体的报道,之后是蔓延到全国各地的有组织的活动,直至最后政府的表态。这一连串的事件波及国家政治和经济,对社会秩序造成了一定的冲击。在这次事件中,网络舆论再次展示了其强大的力量,通过网络舆论展示了中国人民的巨大凝聚力,有力反击了西方敌对势力的无稽言论。但在看到网络舆论成为维护国家权益的工具的同时,网络舆论中存在的巨大安全隐患也让人担忧。     

A framework for the collective movement of mobile robots based on distributed decisions

A novel framework for the control of the collective movement of mobile robots is presented and analyzed in this article. It allows a group of robots to move as a unique entity performing the following functions: obstacle avoidance at group level, speed control and modification of the inter-robot distance. Its flocking controller is distributed among the robots, allowing them to move in the desired common direction and maintain a desired inter-robot distance. The framework is made up of different modules that modify the behavior of the group thus allowing different functions. They are based on consensus algorithms that allow the robots to agree on different parameters, taking into account which robot has more relevant information. New modules can be easily designed and incorporated into the framework in order to augment its capabilities. It can be easily implemented on any mobile robot capable of measuring the relative positions of neighboring robots and communicating with them. It has been successfully tested using 8 real robots and in simulation with up to 40 robots, demonstrating experimentally its scalability with an increasing number of robots.     

Self-organized coordinated motion in groups of physically connected robots.

An important goal of collective robotics is the design of control systems that allow groups of robots to accomplish common tasks by coordinating without a centralized control. In this paper, we study how a group of physically assembled robots can display coherent behavior on the basis of a simple neural controller that has access only to local sensory information. This controller is synthesized through artificial evolution in a simulated environment in order to let the robots display coordinated-motion behaviors. The evolved controller proves to be robust enough to allow a smooth transfer from simulated to real robots. Additionally, it generalizes to new experimental conditions, such as different sizes/shapes of the group and/or different connection mechanisms. In all these conditions the performance of the neural controller in real robots is comparable to the one obtained in simulation.     

A scaling law between the number of multirobots and their task performance

We researched the efficiency of cooperative behavior using interacting multirobots. In this paper, we assume simple robots with a drive system and the simplest means of interaction, and examine the collective behavior through the task of gathering pucks in a field. The efficiency of group behavior is evaluated by the relation between the number of robots and the task completion time. To evaluate the efficiency of group behavior, we measure the exponent β, which is obtained from the scaling relation between the task completion time and the number of robots. The effectiveness of group behavior is investigated for fractal distributions of pucks. We research their behavior for fractal distributions of pucks and find out that the optimum value of β depends on the dimension of the puck distributions. We also propose a simplified state transition diagram of the group to analyse their characteristics. These results enable us to describe the condition of the field by a variable in the state transition diagram. This work was presented, in part, at the Third International Symposium on Artificial Life and Robotics, Oita, Japan, January 19–21, 1998     

Abstraction and control for Groups of robots

This paper addresses the general problem of controlling a large number of robots required to move as a group. We propose an abstraction based on the definition of a map from the configuration space Q of the robots to a lower dimensional manifold A, whose dimension is independent of the number of robots. In this paper, we focus on planar fully actuated robots. We require that the manifold A has a product structure A=G/spl times/S, where G is a Lie group, which captures the position and orientation of the ensemble in the chosen world coordinate frame, and S is a shape manifold, which is an intrinsic characterization of the team describing the "shape" as the area spanned by the robots. We design decoupled controllers for the group and shape variables. We derive controllers for individual robots that guarantee the desired behavior on A. These controllers can be realized by feedback that depends only on the current state of the robot and the state of the manifold A. This has the practical advantage of reducing the communication and sensing that is required and limiting the complexity of individual robot controllers, even for large numbers of robots.     

Design of the “army-ant” cooperative lifting robot

This paper describes the design and development of a new class of mobile robot. These small robots are intended to be simple and inexpensive, and will all be physically identical, thus constituting a homogeneous team of robots. They derive their usefulness from their group actions, performing physical tasks and making cooperative decisions as a coordinated team. All mechanical and electrical design aspects are decided with the group-dynamical behavior in mind. Because of their behavioral resemblance to their insect counterparts, they have been named "army ant" robots     

Emotions and temperament of robots: Behavioral aspects

An approach to the control of robots behavior based on the emotion and temperament mechanism is proposed. It is shown that these psychological features can be simulated fairly simply. The proposed emotion-based architecture of the robot control system leans upon the Simonov informational theory of emotions, while the specific features of temperament are reduced to a two-parameter model of the excitation-inhibition type. Experiments performed with mobile robots are described. These experiments demonstrate a set of various types of robots’ behavior: melancholic, choleric, sanguine, and phlegmatic. All these types were implemented using the so-called temperament controller, which determines a balance between the excitation and inhibition parameters of the robot control system. An FSM-based model of temperament is also proposed that makes it possible to describe the behavior of an individual. Using this model, it is shown that, for performing certain collective behavior tasks, it is useful to have in the group individuals with different behavior so that this behavior also depends on the individual emotions and temperament of robots.     

Closed-Curve Path Tracking for Decentralized Systems of Multiple Mobile Robots

In this paper we address the problem of making a group of mobile robots cooperatively track an assigned path. We consider paths described by completely arbitrarily shaped closed curves. The proposed control strategy is a fully decentralized algorithm and it does not require any global synchronization. The desired behavior is obtained by means of some properly designed artificial potential functions. Analytical proofs are provided to show the asymptotic convergence of the system to the desired behavior. Matlab simulations and experiments on real robots are described as well for validation purposes.     

Small robot agents with on-board vision and local intelligence

We designed a family of completely autonomous mobile robots with local intelligence. We developed a controller with a variety of digital and analog I/O facilities and the operating system RoBIOS, which allows maximum flexibility. The robots have a number of on-board sensors, including vision, and do not rely on global sensor systems. The on-board computing power is sufficient to analyze several color images per second. This enables the robots to perform several different task such as navigation, map generation or intelligent group behavior and does not limit them to the game of robot soccer.     

Animal–robots collective intelligence

In this paper we try to define – as ethologists – the easiest ways for creating such a synergy around a common project: mixed groups of interacting animals and robots. The following aspects are explored. (1) During this century, ethology has accumulated numerous results showing that animals' interactions could be rather simple signals and it is possible to interact with animals not only by mimicking their behaviors but also by making specially designed and often simple artifacts. (2) The theory of self-organization in animal societies shows that very simple, but numerous, interactions taking place between individuals may ensure complex performances and produce Collective Intelligence (CI) at the level of the group. This context is the most interesting to develop mixed animal–robots interactions. (3) An experiment using an artifact interacting within a CI system in the wild (gull flocks) is developed. (4) Cases of robots making CI on their own have been developed. (5) Considering (4) and (5), what are the expected difficulties to mix robots and animals in CI systems. (6) Why develop such mixed societies? The control of interactions between artificial systems and living organisms is a key aspect in the design of artificial systems, as well as in many agricultural, medical, scientific and technical fields. Such developments refer generally to human–robots interactions, leading to further complexity of the behavior and algorithms of robots. However, complex performances do not always require complex individual behavior and interesting developments may also refer to simpler interactions. As far as we know, experiments studying animal–robots interactions are rather anecdotal, with a naíve point of view on animal behavior and are often published in non-scientific journals. However, we are very convinced that robotics has much to learn from ethology while robotics in turn may surely help ethology to explore animal behavior. In this paper we try to define – as ethologists – the easiest ways for creating such a synergy around a common project: mixed groups of interacting animals and robots.     

Development of A Behavior‐Based Cooperative Search Strategy for Distributed Autonomous Mobile Robots Using Zigbee Wireless Sensor Network

To achieve efficient and objective search tasks in an unknown environment, a cooperative search strategy for distributed autonomous mobile robots is developed using a behavior‐based control framework with individual and group behaviors. The sensing information of each mobile robot activates the individual behaviors to facilitate autonomous search tasks to avoid obstacles. An 802.15.4 ZigBee wireless sensor network then activates the group behaviors that enable cooperative search among the mobile robots. An unknown environment is dynamically divided into several sub‐areas according to the locations and sensing data of the autonomous mobile robots. The group behaviors then enable the distributed autonomous mobile robots to scatter and move in the search environment. The developed cooperative search strategy successfully reduces the search time within the test environments by 22.67% (simulation results) and 31.15% (experimental results).