Reaping the benefits of innovative IT: the long and winding road

The expectation that banks and other service industries will do better through investments in innovative IT applications requires a fundamental understanding that benefits do not stem from technology alone. Innovative IT applications have the potential to change the way banks conduct their business and, as such, must be viewed as a major organizational change. This study examines how different stakeholder perspectives of innovative IT influence the implementation process, attitudes toward usage, and perceived benefits in mandatory use situations. Using a case study methodology, the authors explore these issues in the context of a major IT initiative underway at a multibank holding company headquartered in the Midwest US. They found that innovative IT applications involve change that is inherently a long-term endeavor requiring transformations of individual skills and organizational processes and practices. Their research suggests that the time lag before realization of performance gains is affected by the implementation process. Their findings have a number of generalizable lessons for practice as well as implications for future research     

有线网上的商务应用

总的来看,有线网上的商务应用与民用的区别是:(1)前者能提高工作效率,后者主要是娱乐消遣;(2)在广域网(WAN)上运行;(3)要求高带宽和双向连接。图2列出了有线接入网上的商务应用框架。图2中支持这些商务应用的基础技术包括电缆调制解调器(Cable Modem)、虚拟专用网和IP话音技术。     

Performance evaluation of TCP‐based applications over DVB‐RCS DAMA schemes

Transmission Control Protocol (TCP) performance over Digital Video Broadcasting—Return Channel via Satellite (DVB‐RCS) standard is greatly affected by the total delay, which is mainly due to two components, propagation delay and access delay. Both are significant because they are dependent on the long propagation path of the satellite link. The former is intrinsic and due to radio wave propagation over the satellite channel for both TCP packets and acknowledgements. It is regulated by the control loop that governs TCP. The latter is due to the control loop that governs the demand assignment multiple access (DAMA) signalling exchange between satellite terminals and the network control center, necessary to manage return link resources. DAMA is adopted in DVB‐RCS standard to achieve flexible and efficient use of the shared resources. Therefore, performance of TCP over DVB‐RCS may degrade due to the exploitation of two nested control loops also depending on both the selected DAMA algorithm and the traffic profile. This paper analyses the impact of basic DAMA implementation on TCP‐based applications over a DVB‐RCS link for a large set of study cases. To provide a detailed overview of TCP performance in DVB‐RCS environment, the analysis includes both theoretical approach and simulation campaign. Copyright © 2009 John Wiley & Sons, Ltd.     

有线网上的商务应用

因特网不仅改变了我们日常生活中的通信方式,而且从根本上改变了我们从事商务活动的方式。现在,信息交换早已远远超出在楼房内或在公司内通信的范畴。商务应用也远远超出电子函件和公司内部网的范围。更确切地说,我们与远地办公室交换工程设计意见;与供应商共享库存数据库;从     

实时与非实时综合应用在多个信号的测量

基于信号的不同特性与要求,将实时测量和非实时测量综合应用在多个信号的测试。本文在LabVIEW的通用测试程序中,引入LabVIEWRT的实时测试,同时应用LabVIEW Simulation Interface调用Matlab构建模型,应用Datalogging and Supervisory Module完成数据的即时存储。本文编写Matlab来完成房屋的温度模型和直流电机物理模型,并调入LabVIEW的真实采集环境进行半物理仿真,同时编写LabVIEW非实时控制模块和LabVIEW实时控制模块控制仿真模型,从而完成实时和非实时监控。     

ATM上的实时多媒体业务

随着Internet的迅速发展,人们不仅要求在分组网络上传输数据,还要求分组网络能够传输实时多媒体业务,即将语音等实时业务和数据传输融合到一个单一的分组网络中。目前,在语音通过分组网络传输方面,出现了VoATM、VoIP。VoATM在利用ATM技术服务质量（QoS）保障的同时,为语音在ATM网络上的传输提供了特殊网关,将PSTN语音业务进行抽样编码,使其能够在ATM上传输,这使VoATM有可能在长途电话服务上获得成功应用。而VoIP因为缺乏普遍认可或广泛应用的信令标准和资源预留,而面临着更大的挑战。然而,对于能够在其内部网内提…     

XTP over AAL 5 for multimedia applications

The emerging of high-speed networks provides the infrastructure for handling a wide set of new applications, covering distributed multimedia cooperative features. The new quality of service provided by these networks as well as the various requirements of these applications raises new architectural and protocol issues and trends to cope with this paradigm. The transport layer is one point of interest because it is the one between processing and communication. Also, aal type 5 is the most popular atm adaptation layer today and is available in all atm products. In this paper, we briefly overview the xtp and aal 5 key characteristics, then analyse how these two protocols can work together in order to provide the required services to the user’s applications.     

TCP Performance over UMTS-HSDPA System

The performance of TCP based applications in a UMTS-HSDPA system is evaluated, using an analytical model. HSDPA (High Speed Downlink Packet Access) is an evolution of the UMTS standard over the air interface to achieve higher bit rates through the introduction of adaptive modulation and coding, Hybrid ARQ, fast scheduling, fast cell selection and MIMO. The proposed model is used to evaluate the effect of the TCP protocol on the bit rate of various data services (at 32, 64 and 128 kbps). The results show that the bit rate per flow decreases strongly if congestion in the wired network increases. The interaction between cell capacity and the TCP layer is also studied. A semi-analytical model to evaluate the cell capacity is also presented in this paper, and the correspondence between cell capacity and guaranteed TCP bit rate is reported in this paper for a Round Robin scheduler. The findings are supported by simulation results.     

Innovating and management of the knowledge base on the example of IT applications

This paper presents ongoing research in standardised subfields of information technology (IT). This is an isolated segment of a comparative statistical analysis of trends in global (ISO) and local (SRPS) standardisation of knowledge sources (KS) in the subfields of IT applications (ICS2?=?35.240). The ultimate goal of the study is to define management of knowledge base systems. The specific objectives of this research are related to the presentation of original results, comparative criteria, and defining the level of innovativeness (based clustering) in forming a knowledge base (KB), from the knowledge source to modelling, implementing and improving the knowledge base system on the example of the subfields of IT applications.     

Hierarchical queue‐length‐aware power control for real‐time applications over wireless networks

We consider the problem of optimal power control for quality‐of‐service‐assured wireless communication. The quality of service (QoS) measures of our consideration are a triplet of data rate, delay, and delay bound violation probability (DBVP). Our target is to develop power control laws that can provide delay guarantees for real‐time applications over wireless networks. The power control laws that aim at optimizing certain physical‐layer performance measures, usually adapt the transmission power based on the channel gain; we call these “channel‐gain‐based” (CGB) power control (PC). In this paper, we show that CGB‐PC laws achieve poor link‐layer delay performance. To improve the performance, we propose a novel scheme called hierarchical queue‐length‐aware (HQLA) power control. The key idea is to combine the best features of the two PC laws, i.e., a given CGB‐PC law and the clear‐queue (CQ) PC law; here, the CQ‐PC is defined as a PC law that uses a transmission power just enough to empty the queue at the link layer. We analyze our proposed HQLA‐PC scheme by the matrix‐geometric method. The analysis agrees well with the simulation results. More importantly, our results show that the proposed HQLA power control scheme is superior to the corresponding CGB‐PC in both average power consumption and effective capacity. Copyright © 2010 John Wiley & Sons, Ltd.     

Performance of synchronized master-slave closed-loop control of AC electric drives using real time motion over ethernet (RTMoE)

Multi-motor driving servomechanisms are widely used in modern industry for high-performance applications involving synchronized control of position, speed, acceleration and deceleration. Several synchronous control schemes have been developed to achieve good speed or position tracking regardless of various uncertainties and load torque perturbations. However, these solutions have some disadvantages, namely the costs associated with the necessary interfaces to transmit hardware synchronization signals between multiple drives and difficulty to integrate other tools and communication networks. Recently, Industrial Ethernet network-based control systems are becoming increasingly popular for industrial applications and factory automation. To overcome some of these disadvantages this paper proposes an approach that uses a real-time Ethernet applied to a dual-motor master-slave synchronization system, without introducing significant degradation of speed or position in the application performance. With this solution the position reference from the master encoder is transmitted by the real-time Ethernet instead of the classic hardware interface. This allows the integration of different tools and the explore of other functionalities of electric drives. The performance of the proposed solution was tested using industrial equipment through several practical experiments. It was also compared with an existing solution based on hardware interfaces, to identify advantages, limitations and cost savings of using real-time Ethernet networks solutions in synchronized AC electric drives.     

The Effect of Incentives on the Performance of International IT Standardization Experts

In this paper, we investigate the determinant factors of performance of global standardization experts in their standardization activities. Standards experts of various nationalities were surveyed to assess incentives that may positively influence the performance of standards professionals. As a basis for this study, we make three main assumptions. First, incentives can be important determinant factors of performance among standards experts. Second, standardization is in the public interest, insofar as the efficiency gains resulting from standardization benefit society as a whole. Third, based on this assumption that standardization is in the public interest, we propose that performance determinants for standardization activities tend to be non‐monetary in nature rather than monetary. We find that, in order to improve performance among international standards experts, a better understanding of their aspirations and needs must be gained so that appropriate incentives may be proposed to them. Our analysis reveals that the two most important determinant factors of performance are the recognition of the professional status of international standards experts, and an environment providing support systems to help them perform to their fullest potential.     

Performance analysis of coded space‐time adaptive detection in DS/CDMA systems over Rayleigh fading channels

In this paper, we study the use of channel coding in a direct‐sequence code‐division multiple‐access (DS‐CDMA) system that employs space‐time adaptive minimum‐mean square‐error (MMSE) interference suppression over Rayleigh fading channels. It is shown that the employment of adaptive antenna arrays at the receiver can assist in attenuating multiuser interference and at the same time speeds‐up the convergence rate of the adaptive receiver. In this work, we assess the accuracy of the theoretical results developed for the uncoded and convolutionally coded space‐time multiuser detector when applied to the adaptive case. It is found that the use of antenna arrays brings the receiver performance very close to its multiuser counterpart. Using performance error bounds, we show that a user‐capacity gain of approximately 200% can easily be achieved for the space‐time adaptive detector when used with a rate 1/2 convolutional code (CC) and a practical channel interleaver. This capacity gain is only 10% less than the gain achieved for the more complicated multiuser‐based receiver. Finally, we perform a comparison between convolutional and turbo coding where we find that the latter outperforms the former at all practical bit‐error rates (BER). Copyright © 2006 John Wiley & Sons, Ltd.     

TCP在无线链路上的性能问题

文章以无线LAN和蜂窝通信系统为例,首先回顾了无线链路的特征;然后概述了TCP/IP协议组用于无线链路时的性能问题,并为解决这些问题介绍了几种建议,验证了它们的优点和局限性;最后讨论了未来无线系统的发展方向,以及它们即将面临的与TCP性能有关的挑战.     

IPv6视频监控系统的实现与奥运创新应用

随着信息通信宽带产业的发展,视频多媒体应用已普遍得到电信运营商的重视,并将其作为重点转型业务之一。目前视频监控市场正由行业专业监控向社会公共领域及家庭个人普及,以及由分散分割的监控专网向大规模部署、集中管理的运营级公众服务方向发展,视频监控已越来越得到广泛应用。本文结合中国下一代互联网总体发展目标,论述了基于IPv6的视频监控系统的技术研发、实现方案和应用情况。     

基于Internet的实时视频信号传输研究进展

随着Internet带宽和计算机处理能力的迅速提高,实时Internet视频传输在科研和工业领域引起了极大的研究兴趣。本文介绍了实时Internet视频传输的基本方法,针对Internet分组的丢失特性,讨论了具有差错复原能力的视频压缩与编码技术,详细介绍了Internet视频传输的信源／信道联方编码技术,并对今后的研究方向进行了概括的描述。     

卫星链路上TCP协议问题透析

本文是卫星链路上 TCP协议问题及解决方案的综述。文章归纳了卫星链路上 TCP协议存在的问题 ,并且分类总结了已经提出来的各种解决方案 ,进行了详细的分析比较 ,提出了作者的观点