MPLS技术在唐山有线电视综合信息网数据平台中的设计与应用

MPLS技术是一项具有多协议支持的技术，它综合利用了网络核心的交换技术和网络边缘的IP路由技术各自的优点，它将标记分配给多协议的数据桢以便在基于我展品信元的网络中传输。它能够提供现有传统IP路由技术所不能支持的要求保障QoS的业务，通过MPLS技术，我们可以提供各种新兴的增值业务，有效的实施流量工程和计费管理措施，扩展和完善更高等级的基础服务。     

基于ADO．NET构建数据库访问中间层类库的研究

为了使数据设计和程序开发完全分离,减少二者间耦合,达到项目便于分割,任务便于独立,提高效率,减少错误的目的。采用构建数据库访问类库的方法。本方法已在理论考核系统、远程辅助教学系统等多个系统中做了实验,并验证了其效果的良好性。得到了一个结论,有了这样一个中间层,项目主程序的开发者,可以完全不需要了解数据的细节,只需要构建这个类库的对象,通过对这些对象的读写操作,就可以完成对数据库的操作。     

The ITU's role in the restructuring revolution

The ITU recognizes a twofold mission: to monitor regulatory policy changes and technological developments to be in a position to advise members; and to link restructuring changes to overall basic telecommunication development needs. The fundamental goal of the international community in this sector is to achieve universal access to basic telecommunications services. In this context, restructuring is but one component, although the global challenge is to work together to ensure that the restructuring revolution paves the way to filling the development gap. It is readily admitted that new technologies such as mobile satellite systems enable developing countries to leapfrog their infrastructure problems, and that governments recognize the potential benefits of these new technologies and the need to reform regulations in order to facilitate the introduction of these services     

Polyelectrolytes-coated gold nanoparticles detection by PEDOT:PSS electrochemical transistors

Electrochemical transistors made of PEDOT:PSS are used to detect different polymeric shells used to functionalize the nanoparticles for drug delivering. The devices were realized drawing their configuration directly on glass with a micro-syringe and micro-positioning system. This permits a great flexibility in the definition of the needed geometry giving the possibility to maximize the signal to the different polymeric shells. The realized devices exhibit different responses respect to the functionalized nanoparticles and in particular respect to the polymer used for their functionalization. The linear behavior observed gives the possibility to use these devices to detect the quantity of polymer loaded on the nanoparticles. This opens to the possibility to determine the quantity of drugs that could be loaded inside the functionalized shells and also to detect the kinetics of drug delivery or, even, to monitor the stability of the nanoparticles themselves.     

浅析卷烟准时配送的实现

在卷烟制造企业的产品销售中,能否准时地将卷烟配送到商业客户的手中,提高配送效率,是新常态下服务满意度提升的一个重要条件。那么在网络和信息系统发达的今天,传统的企业必须与互联网拥抱在一起,寻求效率和满意度提升新途径。立足于固有的资源,为实现客户满意度提升和客户订货需求的增加,如果仅仅采用企业原有知识和技能框架是不足以满足要求的。我们要了解的是什么使客户能够创造出核心的价值得以实现业务的增值。由于小批量多批次订货模式的改变,如何保证产品准时到货,如何利用互联网及信息系统为客户提供可感知的便利操作。本文对卷烟如何实现准时配送的问题进行一个浅析。     

Satisfactory content delivery scheme for QoS provisioning in delay tolerant networks

We deal in this article with the content forwarding problem in delay tolerant networks (DTNs). We first formulate the content delivery interaction as a noncooperative satisfaction game. On one hand, the source node seeks to ensure a delivery probability above some given threshold. On the other hand, the relay nodes seek to maximize their own payoffs. The source node offers a reward (virtual coins) to the relay, which caches and forwards the file to the final destination. Each relay has to solve the dilemma of accepting/rejecting to cache the source's file. Cooperation incurs energy cost due to caching, carrying, and forwarding the source's file. Yet when a relay accepts to cooperate, it may receive some reward if it succeeds to be the first relay to forward the content to the destination. Otherwise, the relay may receive some penalty in the form of a constant regret; the latter parameter is introduced to make incentive for cooperation. Next, we introduce the concept of satisfaction equilibrium (SE) as a solution concept to the induced game. Now, the source node is solely interested in reaching a file delivery probability greater than some given threshold, while the relays behave rationally to maximize their respective payoffs. Full characterizations of the SEs for both pure and mixed strategies are derived. Furthermore, we propose two learning algorithms allowing the players (source/relays) to reach the SE strategies. Finally, extensive numerical investigations and some learning simulations are carried out to illustrate the behavior of the interacting nodes and to give some insightful thoughts on how to fine‐tune the network setting.     

抑制传导耦合方法研究

传导耦合是一种重要的串扰方式,它对导线及电缆的干扰很大。电容性耦合和电感耦合是传导耦合的两种形式,通过对它们构成机理以及原理的分析,提出了抑制它们的几种方法,如对于电容性耦合可以采用减小导线的长度、增大线间距,平衡法,对干扰源和被干扰源进行屏蔽等方式进行抑制干扰;对于电感耦合可以用减小互感,局部形成耦合环,对干扰源进行屏蔽等方式来对干扰进行抑制。     

Comparison of a Set of Power Distribution Parameters for Intraoperative EEG Monitoring

This study was conducted to compare the relative performance of 19 univariate EEG power distribution parameters in terms of their sensitivity to changes in the background (stationary) EEG activity and insensitivity to broad-band interference. Each of the parameters partitioned the power spectrum into two frequency subbands, each subband containing a fixed specific percentage of the total power. The EEG signals recorded from ten patients during induction with thiopental sodium were used in the study. Two sensitivity functions were defined to compare the sensitivity of the parameters to the effects of thiopental sodium. Parameter changes were compared to bandwidth changes during induction to evaluate their sensitivity to broad-band interference. The results of the study showed that the parameters in the middle of the percentile scale were more sensitive to background EEG changes produced by thiopental sodium than were those at either end of the scale. Sensitivity to broad-band interference was found to be directly proportional to percentile. Within the limits of this study, a parameter between the 25th and 30th percentiles would be the most suitable parameter to monitor intraoperatively.     

Perspectives on next generation mobile

Employees in today’s enterprises are requesting their employers to allow them to work in a flexible manner. Work is no longer a place to go to but an activity to be undertaken. With developments in technology, the activity can be undertaken whenever and wherever it is convenient for the employees. Increasing demands by employees to be able to work in this way creates a tension within the enterprise as CIOs and finance officers strive to manage the costs and the infrastructure required to support this way of working. Over time, this situation will change as technology allows users to roam securely and seamlessly between networks accessing the required applications and information from a single suitably enabled device. This will tend to reduce the underlying costs as the best connection can be used. Service management will remain a challenge but become a better understood problem as the ’stove-pipe’ nature of current solutions is removed. For this change to be brought about, some enabling technologies have to be put in place. This paper considers issues surrounding next generation mobile solutions and shows how converged services can be used to deliver the vision of being able to work from any place, at any time. Consideration is given to how roaming from fixed to wireless networks can be achieved by reusing already established authentication principles that are now deployed in wide area wireless networks. In order to do this, open methods of managing user identity need to be devised and implemented and approaches to this are also discussed. The paper concludes with a consideration of some of the research challenges that remain to be solved. HP     

Low response time context awareness through extensible parameter adaptation with ORCA

Ubiquitous computing applications or widespread robots interactions execute in unforeseen environments and need to adapt to changeful available services, user needs, and variations of the environment. Context-awareness ability addresses such a need, enabling, through adaptation rules, applications to react to the perceived dynamic variations. Responses to adaptation have to be quick enough to maximize the time during which the application is coherent with its environment. Adaptation rules, associating variations of the environment to application reactions, are usually established at design time. However, in unforeseen and partially anticipated environments, we claim that adaptation rules have to be dynamically extensible to match previously unexpected variations. Our approach enables rule composition and ensures a deterministic result. We propose to use parameter adaptation to quickly respond to environmental variations and dynamic compositional adaptation to provide extensibility to the parameter adaptation. To foster even lower response times, we internalize context-awareness processing and decision into the application.     

Use of induced acceleration to quantify the (de)stabilization effect of external and internal forces on postural responses

Due to the mechanical coupling between the body segments, it is impossible to see with the naked eye the causes of body movements and understand the interaction between movements of different body parts. The goal of this paper is to investigate the use of induced acceleration analysis to reveal the causes of body movements. We derive the analytical equations to calculate induced accelerations and evaluate its potential to study human postural responses to support-surface translations. We measured the kinematic and kinetic responses of a subject to sudden forward and backward translations of a moving platform. The kinematic and kinetics served as input to the induced acceleration analyses. The induced accelerations showed explicitly that the platform acceleration and deceleration contributed to the destabilization and restabilization of standing balance, respectively. Furthermore, the joint torques, coriolis and centrifugal forces caused by swinging of the arms, contributed positively to stabilization of the Center of Mass. It is concluded that induced acceleration analyses is a valuable tool in understanding balance responses to different kinds of perturbations and may help to identify the causes of movement in different pathologies.     

一个新的门限多重代理多重签名方案

In the Paper, we proposed a threshold mult- proxy multi-signature with share verification.In the scheme,a subset of original signers allows a designated group to proxy signers to sign on behalf of the original group, A message m has to be signed of proxy signers who can represent the proxy group. Then, the proxy signature is sent to the verifier group.A subset of verifiers in the verifier group can also represent the group to authenticate the proxy signature.In othe words,some threshold values will be given to indicate the number of persons to represent a group to authorize the signing capability or to sign a messagye or to verify the proxy signature.     

Preparing technical communication students to play a role on the translation team

Technical communicators need to be prepared for the challenges of international communication. This tutorial focuses on the need for technical communication faculty to prepare students to be skilled intercultural communicators and to play a role on the translation team. The tutorial begins with a discussion of the importance of writing for translation in the international workplace and then presents specific assignments designed to instruct students in intercultural communication and give them experience writing for translation. In addition to introducing students to the cultural issues that impact the creation of documentation for international audiences, these assignments also serve to reinforce core skills recognized as vital to professional success in the field of technical communication. Taken together, these assignments can be used as the basis for a course in international technical communication. An appendix to the tutorial includes numerous resources available to faculty who want either to develop a course in international technical communication or to include some of the assignments in existing technical communication courses.     

TCP-DCR: a novel protocol for tolerating wireless channel errors

This paper presents TCP-DCR, a set of simple modifications to the TCP protocol to improve its robustness to channel errors in wireless networks. TCP-DCR is based on the simple idea of allowing the link-level mechanism to recover the packets lost, due to channel errors, thereby limiting the response of the transport protocol to mostly congestion losses. This is done by delaying the triggering of congestion response algorithms for a small bounded period of time /spl tau/ to allow the link-level retransmissions to recover the loss due to channel errors. If at the end of the delay /spl tau/ the packet is not recovered, then it is treated as a packet lost due to congestion. We analyze TCP-DCR to show that the delay in congestion response does not impact the fairness towards the native implementations of TCP that respond to congestion immediately after receiving three dupacks. We evaluate TCP-DCR through simulations to show that it offers significantly better performance when channel errors contribute more towards packet losses in the network with no or minimal impact on the performance when congestion is the primary cause for packet loss. We also present an analysis to show that the number of flows in the network significantly influences protocol evaluation in the wireless networks.     

IEEE802.11b协议在户外无线网络传输的应用与改进

文章针对IEEE802．11b协议在户外传输中存在的问题进行研究,通过对CSMA／CA协议的访问流程进行修改,利用时间片选择的随机性,降低不同站点发送数据的冲突概率,有效解决了“隐藏结点”和“低数据吞吐量”等问题。从而提高了在户外现场监控设备图象传输的效率,系统已经成功应用于油田的无人值守监控系统。     

Security-State Adjustable Gateway with Threat-Based Configuration

This paper proposes a configurable secure gateway architecture which allows the system administrators to dynamically configure the security mechanisms upon deployment or during the run-time. Rather than allowing the system administrators to turn on or off individual security mechanisms, the proposed architecture allows the administrators to configure the gateway based on the security threats to be overcome. The current common architecture leads to tremendous administration overhead and increases the chance of misconfiguration vulnerability. We propose a novel software architecture to aid the product designers to avoid the misconfiguration vulnerability and the end-users to ease the administration overhead. The software architecture makes use of the threats to the gateways and the occurrence relation between the threats to configure the security software components on the gateways. With the software architecture, the end-users can focus on determining the desired security features rather than the software configuration. Moreover, the architecture allows the product designers or security service to incrementally revise the software configuration when new threats appear.     

中间件技术在遗留系统改造中的应用

遗留系统是企业建立新信息系统时,面临的首要问题。在简单介绍了中间件技术的基础上,提出利用中间件技术通过构件化实现对遗留系统改造的方法,改造过程包括4个阶段:恢复遗留系统的软件体系结构;设计目标系统的软件体系结构;重新构造目标系统的构件;实现基于构件的目标系统。实践证明,该方法对遗留系统的再工程具有较大的实用价值。     

一种基于Internet的嵌入式网络测控系统接口的设计

传统的Internet应用以PC为中心,未来的Internet应用将转向以嵌入式设备为中心。据预测,将来在Internet上传输的信息中将有70%的信息来自于小型嵌入式系统。提出了由单片机 操作系统 嵌入式TCP/IP协议栈 测控对象来实现嵌入式网络测控系统接口的一种实现方法。并给出了嵌入式TCP/IP协议栈在单片机上的实现方法、讨论了通用网关接口(CGI)实现的作用以及测控系统的主要作用的基本原理。     

A New DAO Pattern with Dynamic Extensibility

Currently existing data access object （DAO） patterns have several limitations. First, the interface of the patterns and business objects is tightly-coupled, which affects seriously the dynamic extensibility of software systems. Second, the patterns have duplicated implementation codes, which add to difficulties of system maintenance. To solve these problems, a new DAO pattern with stronger independency and dynamic extensibility is proposed in this paper. An example is given to illustrate the using process of the new DAO pattern. The greatest advantages of the new DAO pattern are as follows. If any business object is needed to add to the system, we do not have to modify any codes of the class DAO Factory. All we need to do is to modify the mapping file. Furthermore, because we have only one DAO implementation class to accomplish all the data access to business objects, if some SQL statements are needed to be modified, all we need to do is to modify the DAO implementation class but not need to modify any business objects.     

Behavior and Capability Based Access Control Model for Personalized TeleHealthCare Assistance

With the growing proportion of dependant people (ageing, disabled users), Tele-assistance and Tele-monitoring platforms will play a significant role to deliver an efficient and less-costly remote care in their assistive living environments. Sensor based technology would greatly contribute to get valuable information which should help to provide personalized access to the services available within their living spaces. However, current access control models remain unsuitable due to the lack of completeness, flexibility and adaptability to the user profile. In this paper, we propose a new access control model based on the user capabilities and behavior. This model is evaluated using the data sensed from our tele-monitoring platform in order to assist automatically the dependent people according to the occurred situation. The design of our model is a dynamic ontology and evolving security policy according to the access rules that are used in the inference engine to provide the right service according to the user’s needs. Our security policy reacts according to the detected distress situation derived from the data combination of both the wearable devices and the pervasive sensors. The security policy is managed through the classification and reasoning process. Our classification process aims to extract the behavior patterns which are obtained by mining the data set issued from our Tele-monitoring platform according to the discriminating attributes: fall, posture, movement, time, user presence, pulse and emergency call. Our reasoning process aims to explore the recognized context and the extracted behavior patterns which set up the rule engine to infer the right decision security policy.