泛在网络的Multi-Agent系统模型

未来的泛在网络是一个开放的巨复杂系统,面临局部自治性、异构性、复杂性、混沌性等挑战性问题.研究了泛在网络特性、多Agent逻辑系统语法,语义模型,将泛在网络抽象为由具体特定信念、期望、义务和能力等认知成分的Agent组成的认知系统.同时,设计了一种基于Multi-Agent的泛在网络体系结构,并通过举例形式针对泛在网络中移动性管理问题进行了基于多Agent的形式逻辑描述.为设计未来泛在网络环境下的大规模、复杂的网络服务和应用开辟一条新颖的途径.     

Energy-efficient network memory for ubiquitous devices

Energy and delay tradeoffs occur when a design moves some or all local storage out of the embedded device and into a remote server. Using the network to access remote storage in lieu of local memory can result in significant power savings.     

Robust video communication for ubiquitous network access

Ubiquitous network access implies that video can be streamed to portable devices whether they are moving outdoors or docked at home. Unfortunately, broadband wireless channels and their wired alternatives present a hostile environment for video communication, which manifests itself in error bursts. This paper presents a robust application layer, channel-coding scheme suitable for data-partitioned, compressed video. Data partitioning prioritizes the more important data within a compressed bitstream. In the scheme, the more important compressed data are protected prior to communication over an access network. In particular, window-growth rateless codes are used. This form of rateless code can be incrementally scaled to reflect the importance of the data being protected. The paper gives details of the scheme for achieving this in the context of an H.264/AVC codec’s picture types and structures. The paper considers how best to apply the scheme to H.264/AVC’s data-partitioning modes in a practical manner. Simulations of error-prone channels show that the proposed unequal protection scheme achieves several dBs of improvement in video quality, when compared with equal protection. The simulations modeled both wireless and wired access networks.     

普适计算网络环境中的密钥预分配方案

普适计算使用大量无线传感器节点组成网络,如何保证通信安全是普适计算所面临的重大问题。提出一种普适计算环境中的三层二项式密钥预分配方案,它能够很好地完成两两簇头间密钥对的生成,同时满足对节点极小的能量损耗、极少的通信负载和存贮空间要求。该方案有效地解决了节点获取攻击问题,提高了网络恢复度;同时成功地解决了多项式密钥预分配方案中的“K-security”问题。     

Parallel computing optimization in the Apollo domain network

The performance of parallel computing in a network of Apollo workstations where the processes use the remote procedure call (RPC) mechanism for communication is addressed. The speedup in such systems cannot be accurately estimated without taking into account the relatively large communication overheads. Moreover, it decreases by increasing parallelism when the latter exceeds some certain limit. To estimate the speedup and determine the optimum degree of parallelism, the author characterizes the parallelization and the communication overheads in the system considered. Then, parallel applications are modeled and their execution times are expressed for the general case of nonidentical tasks and workstations. The general case study allows the structural constraints of the applications to be taken into account by permitting their partitioning into heterogeneous tasks. A simple expression of the optimum degree of parallelism is obtained for identical tasks where the inherent constraints are neglected. The fact that the theoretical maximum speedup is bounded by half of the optimum degree of parallelism shows the importance of this measure     

Exploring context-awareness for ubiquitous computing in the healthcare domain

Ubiquitous technologies have potentials to play major roles in different real world organizational settings. One of the areas where applying ubiquitous technologies has been given a lot of attention is in the healthcare domain. Here, users are frequently on the move while at the same time relying increasingly on centralized computerized information. In this paper, we explore ubiquitous technologies in the real world through two studies in the healthcare domain. First, we look at the use and usability of a ubiquitous electronic patient record (EPR) system distributed on desktop and laptop computers throughout a large hospital. Secondly, we present an extension to this ubiquitous computing environment in the form of a context-aware mobile computer terminal prototype. The usability of the mobile EPR prototype was evaluated in both laboratory and field settings. Our results indicate that the usefulness of a ubiquitous computing environment supporting work activities in healthcare can benefit from context-aware mobile information access. However, interaction design for such systems must be carefully thought out and thoroughly evaluated. Also, while the use of mobile and stationary computers complement each other very well, we found that the usefulness of ubiquitous computing environments in healthcare may benefit from additional elements such as situated displays at key locations and on key objects, and from seamless integration between the different devices comprising the system as a whole.     

A ubiquitous manufacturing network system

In this study, a ubiquitous manufacturing network system was constructed. In this system, a customer places an order for an action figure by using a client-side app or a Web-based interface and pays online. The system server then assigns the order to the convenience store nearest the customer's location to print the required action figure. For determining the most suitable convenience store, a fuzzy integer-nonlinear programming model was proposed and solved using two modified fuzzy Dijkstra algorithms. Subsequently, the customer is informed of the location of and route to the recommended convenience store. Two illustrative cases were used to verify the applicability of using the proposed methodology. In addition, compared with an existing mobile guide, the proposed methodology effectively recommended the shortest path for obtaining the required action figure and reduced the waiting time at the convenience store.     

New accelerated algorithm based on domain neural network for solving optimization tasks

We propose a domain model of a neural network, in which individual spin-neurons are joined into larger-scale aggregates, the so-called domains. The updating rule in the domain model is defined by analogy with the usual spin dynamics: if the state of a domain in an inhomogeneous local field is unstable, then it flips, in the opposite case its state undergoes no changes. The number of stable states of the domain network grows linearly with the domain’s size k, where k is the number of spins in the domain. We show that the proposed model is effective for optimization problems, since the use of domain dynamics lowers the number of calculations in k ² times and allows one to find deeper minima than the standard Hopfield model does. The text was submitted by the authors in English.     

泛在学习理论下高等数学网络学习资源优化探讨

基于泛在学习的理论和特点,提出以学习元为基础的网络学习资源建设,避免内容重复构建,提升知识点间的动态关联,构建层次化结构,拓展知识的外延性和内涵性,设定多个模块引导学习.该方法的运用能促进高等数学课程网路学习资源优化,满足学习者无时无刻无处不在的无缝学习,有效提高教学活动的开展,解决现行教学活动中遇到的实际问题.     

A new flow-based fast handover method for Mobile IPv6 network with route optimization

Flow-based fast handover method is designed for Mobile IPv6 network. The FFHMIPv6 uses the flow state information to redirect the traffic flow to a new location. This makes it possible that the reception of packets simultaneously with the BU registration process, thus minimizing the delay experienced in the handover. But it does not consider the route optimization. In this paper, a new flow-based fast handover method is proposed which enhanced the existing flow-based fast handover method to support route optimization. The analysis shows that this scheme has a better performance than the existing FFHMIPv6 scheme.     

基于改进神经网络的非满载车辆路线优化模型

货物流通过程中,目前流行的车辆调度方式--基于简单的神经网络模型设计,造成运输成本的浪费。提出了一种基于改进神经网络的非满载车辆路线优化挖掘模型,来解决运输过程中的非满载车辆调度优化问题。改进的模型通过对非满载车辆时域长度和空域概率的加权、对神经网络稳定状态进行约束、建立非满载车辆起点和终点函数方程生成改进算法配送模型,并通过对新模型进行时间窗加权,合成了改进神经网络非满载车辆挖掘模式。仿真结果表明,该挖掘模型与传统的神经网络计算方法相比,能够提高非满载车辆路线选择效率和正确性,取得了较好的效果。     

Efficient route optimization scheme for nested-NEMO

Network mobility (NEMO) basic support protocol maintains the connectivity when mobile router (MR) of a mobile network changes its point of attachment to the Internet by establishing a bi-directional tunnel between the MR and the home agent (HA). A packet from a correspondent node (CN) traverses through the tunnel to reach the mobile network. Nesting occurs in NEMO when a MR's new attachment point is in another mobile network that has also moved away from its home link. The level of tunneling increases as the level of nesting increases. Multiple levels of tunneling in nested NEMO adds multiple legs to a non-optimized routing path that the IP packets have to traverse in order to reach the final destination. As per our study, an efficient route optimization technique in NEMO, particularly in nested NEMO, is still a research challenge. In this paper, we propose an efficient route optimization scheme for nested NEMO. We use two care-of Addresses for each MR, as well as two types of entries, such as fixed and visiting, in the routing table in each MR. Our route optimization scheme removes the tunnels completely from the nested NEMO in a single step using only one binding update message irrespective of the number of levels in the nest. Our route optimization scheme also works for non-nested NEMO.     

应用组合方法设计普适计算网络安全协议*

给出一种新的安全协议的设计方法——组合设计方法,首先分别实现各个安全目标,然后将它们组合为一个新的安全协议。组合方法设计安全协议具有易于实现、易于验证等优点。给出组合规则,使用组合方法实现了普适计算环境下认证协议及密钥协商协议的设计。     

Self-organized multi-camera network for ubiquitous robot deployment in unknown environments

In this paper, we present a multi-agent system based on a network of intelligent cameras for the easy and fast deployment of mobile robots in unknown environments. The cameras are able to detect events which require the presence of the robots, calculate routes of cameras through which the robots can navigate, and support this navigation. A route is a list of cameras connected by neighbourhood relationships: the cameras may be neighbours if their Fields of View (FOVs) overlap, or if there exists a passable path among them (if their FOVs do not overlap). In our system, all coordination processes are fully distributed, based only on local-interactions, and self-organization. Our system is robust and redundant, and scales well with the size of the environment and the number of cameras and robots. Finally, it is flexible to the environment, to the number of agents used, and to their disposition. In the experimental section, we show the performance of this system in different real world settings.     

公共自行车调度路径优化算法

针对如何计算出每次派出的最佳运输车数和每辆运输车的最优路线的问题,提出了一种用于求解的数学模型,并提出了一种基于改进的混合智能水滴算法。提出了节约算子、启发式算子、最大最小调制机制、变邻域搜索的融合策略。实验证明:所提出的新算法可以求解所述问题,与其他一些算法相比,求解效率更高。     

改进的PMIPv6域内路由优化策略

代理移动IPv6移动节点发生域内切换时,存在着重建路由优化路径时延长、切换开销大的问题,为此,提出一种改进的代理移动IPv6域内路由优化方案.在移动节点即将发生域内切换时,由新接入的移动网关发起切换,减少了切换过程中本地移动锚点的参与,在移动节点接入新网络之前完成优化路径的建立.仿真实验结果表明,新方案在切换时延和切换开销方面的性能优于原有的代理移动IPv6域内路由优化方案.     

大规模泛在RFID网络的构造方法*

依据RFID网络特征和行为的形式化描述,基于发布/订阅系统构建了RFID网络模型。RFID网络是构建在IP网络层之上的重叠网,借助代理(broker)的消息存储转发、匹配和路由机制,实现阅读事件的多对多异步通信,阅读事件与应用之间无须预先确定相关关系。实验验证了这种网络模型的有效性,可以满足将来大规模泛在RFID应用的需求。     

全局优化的神经网络方法

提出了一种解全局优化问题的神经网络模型, 并分析了该模型的收敛性与可行性. 然后, 给出了一个算法, 严格地证明了该算法对优化问题的任意给定的初始点, 都能收敛到它的一个全局极小点. 最后的仿真结果表明, 该算法是有效的.     

Cryptanalysis and improvement of authentication scheme for roaming service in ubiquitous network

Abstract

The paper analyzes a recently proposed secure authentication and key agreement scheme for roaming service in a ubiquitous network. In 2018, Lee et al. proposed a biometric-based anonymous authentication scheme for roaming in ubiquitous networks. But, we found that Lee et al. scheme is prone to the off-line dictionary attack when a user’s smart device is stolen, replay attack due to static variables and de-synchronization attack when an adversary blocks a message causing failure of authentication mechanism. Further, the scheme lacks no key control property and has incorrect XOR calculation. In the sequel, we presented an improved biometric based scheme to remove the weaknesses in Lee et al.’s scheme, which also does not require an update of identity in every session, hence preventing de-synchronization attack. Also, the security of the proposed schemes were analyzed in a widely accepted random oracle model. Further, computational and communication cost comparisons indicate that our improved scheme is more suitable for ubiquitous networks.