Dynamic Scheduling Policy for Patient Flow in a Smart Environment

Given the popularity of smart environment in a hospital involving the participation of a large group of patients, scheduling of patients towards their desired des-tination is still being a challenging issue. With the devel-opment of Internet of Things (IoT), smart environments are increasingly being deployed in various public scenar-ios and in particular, hospitals are an important target environment for smart environments. This paper models a dynamic scheduling policy based on a patient flow sce-nario in order to solve the queuing issue and facilitate peo-ple's experience. The dynamic scheduling policy aims to forward incoming patients to dissolve jams especially at the peaks by giving accurate predication of appointment time. The main modelling technique is a formal method— Performance evaluation process algebra (PEPA). The findings show that the dynamic scheduling policy is able to efficiently improve the patient flow.     

Performance Analysis of the ATM Adaptation Layer 2 (AAL2)

In this paper, we analyze the performance of AAL2 multiplexer for a continuous time Markovian arrival process. AAL2 CPS (Common Part Sublayer) packets are multiplexed in the AAL2 multiplexing queue and transmitted in the transmission queue. This tandem structure suggests that the statistics of AAL2 CPS requires at least 2 dimensional state space. Furthermore, from a network-level point of view, cell multiplexing and de-multiplexing procedures are repeated at each AAL2 switching node. That requires simple analysis model. To solve this problem, we reduce the state space by showing that the output process of multiplexing queue can be modeled with the Coxian distribution. We propose a single dimension analysis model of the CPS transmission queue. When AAL2 convey both real and non real time short packets, QoS management is a problem. This is because the QoS of real time as well as non-real time packets is measured using different metrics – delay and cell loss ratio respectively. Most previous work is concentrated around delay performance due to the real time applications getting the primary attention. From the direct comparison of delay and CLR performance, we show that delay constraint is the dominant parameter in QoS of AAL2.     

The Concept of a Personal Distributed Environment for Wireless Service Delivery

Traditionally wireless service delivery has been restricted in scope to voice and text messaging and has been targeted at a single user device. Increasing interest is now being shown in ubiquitous delivery of services, including many forms of information and entertainment services, over a variety of wireless delivery mechanisms and to a collection of devices controlled by an individual user. These devices may be both local and remote to the user but their combination, and the services provided, form the user’s personal distributed environment (PDE). This paper reviews the concepts associated with a PDE and highlights some of the technical problems which require to be addressed in order to make such an environment a self-organising and attractive proposition from the user viewpoint. The paper defines the elements of a personal distributed environment and concentrates on the issues of personal access management and personal service management. It illustrates typical signalling exchanges required for the control of devices within the PDE and stresses the way in which the PDE may be attached to the core network. The paper will also illustrate a typical scenario in which a PDE might be deployed and will highlight the very important issues of security which must be incorporated in the overall PDE management.     

GPRS通信系统中链路自适应的性能分析

介绍了GPRS移动通信中动态链路自适应的原理,并研究了静态链路自适应和动态链路自适应算法。对基于误块率(BLER)估计值的链路自适应算法进行了改进,并在GSM/GPRS网络仿真系统中加以实现。最后对仿真结果进行了分析。分析表明,动态链路自适应算法可以使GPRS系统在吞吐量和误块率方面获得更好的性能。     

Dynamic Probabilistic Caching Algorithm with Content Priorities for Content‐Centric Networks

This paper presents a caching algorithm that offers better reconstructed data quality to the requesters than a probabilistic caching scheme while maintaining comparable network performance. It decides whether an incoming data packet must be cached based on the dynamic caching probability, which is adjusted according to the priorities of content carried by the data packet, the uncertainty of content popularities, and the records of cache events in the router. The adaptation of caching probability depends on the priorities of content, the multiplication factor adaptation, and the addition factor adaptation. The multiplication factor adaptation is computed from an instantaneous cache‐hit ratio, whereas the addition factor adaptation relies on a multiplication factor, popularities of requested contents, a cache‐hit ratio, and a cache‐miss ratio. We evaluate the performance of the caching algorithm by comparing it with previous caching schemes in network simulation. The simulation results indicate that our proposed caching algorithm surpasses previous schemes in terms of data quality and is comparable in terms of network performance.     

Rate Adaptation Schemes for Different Service Requirements in the Code Division Multiple Access Environment

1IntroductionCodeDivisionMultiplg,.Access(CDMA)isamultipleaccesstechniquebasedonspreadspectrum.Actually,thisisa"secondmodulationtechnique."Inthedirectsequencespreadspectrum,theservicedatastreamisproceededbyaconventionalstandarddigitalmodulation,suchasBinaryPhaseShiftkeying(BPSK),andthenaspreadingsignalisappliedforthesecondtimemodulationoftheservicestream.ThepurposeofspreadspectrumistotransformasignalwithbandwidthB.B.intoanoise-likesignalofmuchlargerbandwidthB..Typically,thepowerofradia…     

A Unit of Information‐Based Content Adaptation Method for Improving Web Content Accessibility in the Mobile Internet

In the mobile Internet, users generally work with handheld devices with limited computing power and small screens. Their access conditions also change frequently. In this paper, we present a novel method supporting intelligent content adaptation to better suit handheld devices. The underpinning is a unit of information (UOI)– based content adaptation method, which automatically detects semantic relationships among the components of Web contents and then reorganizes page layout to fit handheld devices based on identified UOIs. Experimental results demonstrate that our method enables more sensitive content adaptation.     

On the Performance of Link Adaptation Techniques in MIMO Systems

Recent research results on multiple antennas system namely the multiple input multiple output (MIMO) system show that huge potential be it the spectral efficiency or the enhancement in transmission reliability can be achieved. In this paper, with the assumption that the channel is narrowband and the channel coefficients are known at both link ends, we propose and evaluate several link adaptation (LA) algorithms applied to the spatial multiplexing MIMO systems. Depending on the requirements, the LA technique is designed to optimize either the system spectral efficiency or the bit error rate (BER). We also consider the potential use of the maximum eigen beamforming in supporting concurrent users. The results show that efficient use of the channel information could lead to a significant improvement in the system performance.     

载波频率偏移下分布式MIMO系统性能分析

文中针对载波频率偏移对分布式MIMO系统的性能进行了仿真分析,仿真结果表明：载波频率偏移和不理想的信道估计会对系统性能产生较大影响;高阶调制更容易受到载波频率偏移的影响;ZF和MMSE译码算法与传统的Alamouti译码算法相比对于载波频率偏移更加稳健,当｜w-2-w-1｜取值较大时,采用ZF和MMSE译码性能要好于传统的Alamouti译码算法;随着各链路载波频率偏移差别｜w-2-w-1｜的减小,传统的Alamouti译码算法性能不断改善。     

高效液相色谱法测定环维黄杨星D脂质体的含量

目的:建立高效液相色谱法测定环维黄杨星D(CVB-D)脂质体中药物的含量。方法:采用高效液相色谱法在205 nm波长处测定峰面积,计算CVB-D脂质体中CVB-D的含量。结果:CVB-D在0.0202~0.2020mg·mL-1的浓度范围内与峰面积呈良好的线性关系,回归方程:A=461.6C+7.5885,r=0.9994(n=5),平均回收率为99.13%,RSD为0.77%(n=9)。结论:本方法灵敏、准确度高、专属性好,且稳定性、精密度均符合要求,可用于CVB-D脂质体的含量测定。     

多蜂窝分布式系统下行链路性能分析

在多蜂窝分布式通信系统中,当移动用户在蜂窝内运动时,该文研究其下行链路的系统容量变化情况,并且推导出容量的闭合表达式。多数文献采用中心极限定理(CLT)把干扰加噪声项看作高斯白噪声来进行性能分析,其前提条件是干扰项足够多。当干扰项较少时,此种方法存在一定的误差。该文在放宽此限制条件的前提下,利用矩生成函数(MGF)对系统性能重新进行分析并且解决了存在重根时系统容量闭合表达式的推导问题。理论分析和数值仿真表明,此分析方法能更确切地体现信道衰落对干扰信号的影响,进而能更好地描述系统的性能。     

通抗系统战场电磁环境适应能力评估﹡

针对通信对抗系统战场电磁环境适应能力评估问题,通过战场电磁环境对通信对抗系统影响因素的分析,建立通信对抗系统战场电磁环境适应能力评估指标体系,并提出采用模糊评估理论对通信对抗系统战场电磁环境适应能力进行综合评估。在 Matlab 中,运用层次分析法分配各指标权重,构建指标隶属度函数,在不同复杂度等级战场电磁环境下的相关战技指标数据基础上,运用模糊评估方法对通信对抗系统战场电磁环境适应能力进行综合评估。结果表明该方法具有较好的分辨能力和可操作性,此方法已在某试验中得到应用。     

Performance of multiuser network-aware prefetching in heterogeneous wireless systems

We study the performance of multiuser document prefetching in a two-tier heterogeneous wireless system. Mobility-aware prefetching was previously introduced to enhance the experience of a mobile user roaming between heterogeneous wireless access networks. However, an undesirable effect of multiple prefetching users is the potential for system instability due to the racing behavior between the document access delay and the user prefetching quantity. This phenomenon is particularly acute in the heterogeneous environment. We investigate into alleviating the system traffic load through prefetch thresholding, accounting for server queuing prioritization. We propose a novel analysis framework to evaluate the performance of the thresholding approach. Numerical and simulation results show that the proposed analysis is accurate for a wide variety of access, service, and mobility patterns. We further demonstrate that stability can be maintained even under heavy usage, providing both the same scalability as a non-prefetching system and the performance gain associated with prefetching. A preliminary version of this article was presented in the International Conference on Quality of Service in Heterogeneous Wired/Wireless Networks (QShine) 2006. This work was supported in part by the Natural Sciences and Engineering Research Council of Canada and Bell Canada through its Bell University Laboratories R&D program. Ben Liang received honors simultaneous B.Sc. (valedictorian) and M.Sc. degrees in electrical engineering from Polytechnic University in Brooklyn, New York, in 1997 and the Ph.D. degree in electrical engineering with computer science minor from Cornell University in Ithaca, New York, in 2001. In the 2001–2002 academic year, he was a visiting lecturer and post-doctoral research associate at Cornell University. He joined the Department of Electrical and Computer Engineering at the University of Toronto as an Assistant Professor in 2002. His current research interests are in mobile networking and multimedia systems. He received an Intel Foundation Graduate Fellowship in 2000 toward the completion of his Ph.D. dissertation, the Best Paper Award at the IFIP Networking conference in 2005, and the Runner-up Best Paper Award at the International Conference on Quality of Service in Heterogeneous Wired/Wireless Networks in 2006. He is a senior member of IEEE and a member of ACM and Tau Beta Pi. He serves on the organizational and technical committees of a number of major conferences each year. Stephen Drew received his B.A.Sc with honours in Computer Engineering from the University of Waterloo in 2003, and his M.A.Sc in Electrical Engineering at the University of Toronto in 2005 under the supervision of Ben Liang of the Communications group. He is currently employed by General Dynamics Canada, in the engineering research and development team. Da Wang is a third year Electrical Engineering student at the University of Toronto. He has been a recipient of the Adel S. Sedra Outstanding Student Award, the IEEE Canada-Toronto Section Scholarship and the Nortel Institute Undergraduate Scholarship. He held an NSERC award for the summer of 2005.     

窃听者随机分布下智能反射面辅助的MISO系统物理层安全性能分析

针对窃听节点随机分布的MISO系统通信场景,该文分析了智能反射面(IRS)辅助下的安全通信性能。采用随机几何理论,将窃听节点建模为均匀泊松点过程(PPP)。合法发送节点采用天线选择策略,选择最优链路发射信号,并部署智能反射面实时调控反射相移增强链路质量,然后以传输安全中断概率为性能指标,推导了其闭式表达式,分析了反射单元数量、发射天线数量等参数对中断概率的影响,最后给出了最大化安全性能的参数选择策略。仿真结果验证了理论分析的正确性,并表明部署反射面可以在低能耗下提升安全性能。     

Mathematical Modelling on the Quadrature Error of Low-rate Microgyroscope for Aerospace Applications

This paper presents the mathematical modelling on the quadrature error of a microgyroscope due to the imbalance of the asymmetric spring flexures. Quadrature error occurs when the proof mass of a microgyroscope oscillates along an axis that is not exactly parallel to the lateral-axis. The imbalance due to manufacturing variation can cause the proof mass to rotate when a force acts on the proof mass. The proposed mathematical model was verified by the finite element software IntelliCAD, and found to have a good agreement on angles of rotation of comb fingers. The mathematical model provides a new avenue in evaluating the quadrature error system and in saving the overall simulation time.     

The Hybridization of Journalistic Cultures: A Comparative Study of Journalistic Role Performance

Influential research on comparative media systems identifies distinctive models according to which certain countries—particularly advanced democracies—share key features in their journalistic cultures. Revisionist literature has not only emphasized the limitations of such models, but also highlighted the hybridization of journalistic cultures elsewhere. This article tests the hybridization thesis, analyzing the presence of six journalistic roles in print news from 19 countries (N = 34,514). Our findings show patterns of multilayered hybridization in the performance of professional roles across and within advanced, transitional, and nondemocratic countries, with journalistic cultures displaying different types of hybridity that do not resemble either existing ideal media system typologies or conventional assumptions about political or regional clusters. The implications of these findings for future studies are discussed.     

Research of Adaptation of Infrastructures for WSRF in Grid Computing

1IntroductionGrid Computing is a promising emerging technologythat is growingin mindshare andrelevanceintheindus-try .Applications that take advantage of Grids are underdevelopment in both academic and commercial organiza-tions[1].GBuilderis anintegrated development platformwe worked out based on extant Grid Computing toolk-its .It encapsulates the complicated Webservice compil-ing,deploying over these infrastructures ,informs usersof intelligible information about mid-outcomes and er-rors …     

A Prior Model of Structural SVMs for Domain Adaptation

In this paper, we study the problem of domain adaptation for structural support vector machines (SVMs). We consider a number of domain adaptation approaches for structural SVMs and evaluate them on named entity recognition, part‐of‐speech tagging, and sentiment classification problems. Finally, we show that a prior model for structural SVMs outperforms other domain adaptation approaches in most cases. Moreover, the training time for this prior model is reduced compared to other domain adaptation methods with improvements in performance.     

Design and Performance Studies of an Adaptive Scheme for Serving Dynamic Web Content in a Mobile Computing Environment

Currently, people gain easy access to an increasingly diverse range of mobile devices such as personal digital assistants (PDAs), smart phones, and handheld computers. As dynamic content has become dominant on the fast-growing World Wide Web (C. Yuan et al., 2003), it is necessary to provide effective ways for the users to access such prevalent Web content in a mobile computing environment. During a course of browsing dynamic content on mobile devices, the requested content is first dynamically generated by remote Web server, then transmitted over a wireless network, and, finally, adapted for display' on small screens. This leads to considerable latency and processing load on mobile devices. By integrating a novel Web content adaptation algorithm and an enhanced caching strategy, we propose an adaptive scheme called MobiDNA for serving dynamic content in a mobile computing environment. To validate the feasibility and effectiveness of the proposed MobiDNA system, we construct an experimental testbed to investigate its performance. Experimental results demonstrate that this scheme can effectively improve mobile dynamic content browsing, by improving Web content readability on small displays, decreasing mobile browsing latency, and reducing wireless bandwidth consumption