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Communication Software Reuse and Its Supporting Environment

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The Journal of China Universities of posts and telecommunications 1998年第1期5卷 76-77页

作者： Zhou Chen directed by Chen Junliang (department of Information engineering, Beijing {2. of posts and telecommunications, Beijing 100876, P. R. China)

Summary of Software Reuse What we mean 'software reuse' is that we use those software components that were developed before in the new environment. Increasing the productivity and reliability of software is an important task in the development of software. One of the most promising techniques for achieving a significant level of improvement is reuse. The reuse process occurs in every phase of software life cycle: analysis, design, coding, testing, and maintenance. The technologies applied to the reusability can be divided into two major groups depending on the nature of the components being reused. These two major groups are composition approach and generation approach. Both of the approaches have their advantages and drawbacks and there is no agreement upon a unique approach to reusability. We choose composition approach. In this paper, we focus on the research of switching software reuse. There has been no report on the research of communication software reuse in China. The research was carried out in Japan and U.S.A. in the middle of 1980′s. Some references report that there are many advantages in using object oriented language C++ in the development of 5ESS switching system. The software reusability is high and the productivity is also greatly improved. It seems that every switching system has its own software supporting tools or environment. The aim is the same and the reusing technologies are somewhat different. Three main reuse methods are listed below: (1) Paradigm method; (2. Knowledge Base method; (3) Object oriented method. 2. Main Researches (1) Research on the integrated environment for SDL (IES). (2. Convert Abstract Data Types(ADT) in SDL specification to CHILL implementation; By using IF_THEN_ELSE rewriting rules, we prove the correctness of conversion. (3) Introduce the concept of reuse into SDL, and design and implement a SDL ADT/CHILL reusable component library. We focus on the Di

关键词： SDL specification software reuse object orientation

New Ad Hoc QoS Multicast Routing Protocol

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ZTE Communications 2006年第1期4卷 39-42页

作者： Zhao Li (department of Information engineering, Nanjing {2. of posts and telecommunications,Nanjing 2.0003,China)

The application environments of wireless Ad hoc networks require that it should support Quality of Service (QoS). However, that is very difficult because of the inherent characteristics of the wireless channel and the frequent changes of network topology caused by nodes movement. An Ad hoc QoS Multicasting (AQM) protocol can solve this problem by previously reserving the neighbor nodes for tracking resource availability. By considering QoS restrictions of transport delay, loss ratio, bandwidth requirement, delay jitter, and throughout, and by finding the adaptive routing, the AQM protocol can obviously improve the efficiency of multicastsession. The results of network simulation show that QoS is essentially applicable to Ad hoc networks.

关键词： QoS IEEE USA MAODV Hoc New Ad Hoc QoS Multicast Routing Protocol node

Study on Security Technologies for Wireles Network Integration

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ZTE Communications 2006年第2期4卷 43-47页

作者： Feng Min (department of Communication engineering, Nanjing {2. of posts and telecommunications, Nanjing 2.0003, China)

The network integration provides users with a new network with long connection time and a high data rate when needed, but it also brings the defects of all the networks that integrate together into the integrated network. This will cause all kinds of existing and some new security problems in the operation of the integrated network. A complete protection based on recovery is proposed in the paper. It uses the public-key algorithm to authorize and private-key algorithm to encrypt the communicating data. This solution can provide the system with reliable security, and avoid Denial of Service (DoS) of the user. This solution has been proposed lately, and we should further identify the correct action of all the layers and figure out how to react when a legal node is framed by multiple malicious nodes.

关键词： Security USA WLAN node IEEE IPSec Study on Security Technologies for Wireles Network Integration

Segmentation of Moving Objects Using Mathematical Morphology

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The Journal of China Universities of posts and telecommunications 1999年第2期6卷 63-66页

作者： LU Guan-ming BI Hou-jie(department of Information engineering. Naming {2. of posts and telecommunications. Naming, 2.0003, P.R.China ) department of Information engineering Nanjing University of Posts and Telecommunications Nanjing 210003 P.R.China

This paper proposes a motion-based region growing segmentation scheme, which incorporatesluminance and motion information simultaneously and uses morphological tools such as open-close byreconstruction and the region-growing version of the watershed algorithm. The main advantage of this scheme is thatthe resultant objects ore characterized by a coherent motion and foe moving object boundaries are precisely *** results demonstrate the effiency of the Proposed scheme.

关键词： mathematical morphology motion estimation image segmentation object-based video coding

Performance Analysis of Interconnected Communication Networks

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The Journal of China Universities of posts and telecommunications 1998年第1期5卷 72-72,75页

作者： Wang Jianli directed by Zhou Jiongpan (department of Information engineering, Beijing {2. of posts and telecommunications, Beijing 100876, P. R. China)

As the means for communication of users in different communication networks and network resource sharing, communication network interconnection has been paid great attention to in recent years. The performance analysis of internetworks is very important in communication network interconnection, for it is the basis for the study of other problems concerned. The main contribution of this paper is a wide and deep study of performance of internetwork, the construction of systematic performance analysis method for arbitrary internetworks, and of queuing model for gateways. In this paper, the performance analysis of internetwork with arbitrary topology is studied for the first time, and a new method - Node Equivalence of Subnetworks (NES) is proposed. The key step of this method is the node equivalence of subnetworks of all kinds, so we first deeply study the node equivalence, and develop two models for node equivalence. Then we study the node equivalence of CSMA/CD and SLOTTED ALOHA systems by using these models. The results show that the NES method is a systematic method which is suitable for performance analysis of any type of internetworks. The proposed equivalence models is usable with good approximation. The queuing model of gateway is first widely studied in this paper. The queuing model for gateways with packet fragmentation and reassembly is studied for the first time and the analysis method, proposed. In the analysis, two modeling tools, Reversed Switched Poisson Process (RSPP) and Switched Determined Process (SDP), are proposed and RSPP/M/1 queue and SDP/D/1 queue, analyzed. A new method-minislot method is proposed and used for the study of SDP/D/1 queue and performance of ATM multiplexer. In this paper, the interdeparture time distribution of ATM network under some input traffic models is studied and the expression, derived. These results can be used for both performance evaluation of ATM network and the performance of ATM networks intercon

关键词： interconnected communication network internetworks gateway subnetworks node equivalence

Measurement Uncertainty with the Gray Theory

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Measurement Uncertainty with the Gray Theory

AN IMPROVED OPTIMAL CHANNEL SHORTENING ALGORITHM FOR DMT MODULATION SYSTEMS

第二届国际测量仪器与测试自动化学术会议

作者： Yang Jian~(1,2.Lv Naiguang~(1,2.Dong Mingli~2.(1 department of Electronic engineering,Beijing {2. of posts and telecommunications,Beijing 100081,China ) (2.department of Electronic Information engineering,Beijing Institute of Machinery,Beijing 100192.China)

＜正＞It is very important how to evaluate the computer vision measurement *** current evaluating method is based on *** statistical method is based on probability and statistics *** distribution is required, For the computer vision measurement,there are so many factors influencing the ***,small sample size, non-normal distributions and non-repeated measurement can not be applied to statistical *** evaluation of measurement uncertainty is required by most *** paper proposes a new algorithm that using curvature to calculate *** method improves the gray theory and overcome some shortcomings.

关键词： computer vision evaluating uncertainty gray theory curvature error

来源： cnki会议评论

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Journal of Electronics(China) 2007年第6期24卷 748-752页

作者： Liu Shuisheng Shen Yuanlong department of Electronic engineering Nanjing University of Posts ＆ Telecommunications Nanjing 210003 China

In Discrete Multi-Tone (DMT) modulation systems, the well-known technique to overcome the Inter-Carrier Interference (ICI)/Inter-Symbol Interference (ISI) caused by the inadequate Cyclic Prefix (CP) length is to use a Time-Domain Equalizer (TDE) at the receiver front-end. An algorithm used to calculate the coefficients of the optimal shortening Time Domain Equalizer (TDE) was given by Melsa. However, this algorithm requires that the length of the TDE must be smaller than or equal to the memory length of the target impulse response. This paper modifies this algorithm and makes it not only fit for calculating the coefficients of the TDE with arbitrary length, but also have a much less computational time.

关键词： Discrete Multi-Tone (DMT) Time Domain Equalization (TDE) Cyclic Prefix (CP) Channel shortening

Nonlinear Amplifying Loop Mirror for Reducing ASE in Nonsoliton Transmission

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The Journal of China Universities of posts and telecommunications 1996年第2期3卷 35-38页

作者： He Huajie Gu Wanyi Li Guorui and Xu Daxiong(department of Telecommunication engineering, Beijing {2. of posts and telecommunications, Beijing 100088, P. R. China) op.uky.edu department of Telecommunication engineering Beijing University of Posts and Telecommunications Beijing 100088 P. R. China

By using the optic amplifier in Nonlinear Amplifying Loop Mirror (NALM), the input power required to obtain nonlinear input-output relationship reduces to a level that nonsoliton pulse can reach. We use an accurate model to analyze the tralnsmissivity of NALM, and show that it has intensity-filtering character, and can be used to reduce ASE noise of signals amplified by cascaded optic amplifiers. We also find that the saturation of optic amplifier in the loop affects the behaviour of NALM dramatically.

关键词： s: nonlinearity nonsoliton transmission optical amplification ASE

A　Study　on　the　Model　of　Forecasting　System　about　the　Actual　Telephone　Occupation　in　the　Lead　Development

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The Journal of China Universities of posts and telecommunications 1996年第2期3卷 44-51页

作者： Xie Shichang and Xie Xuemei(department of Management engineering, Changchun Institute of {2. and telecommunications, Changchun 130012. P. R. China)

A Inodel Of forecasting system on telephone occupation is proposed with the view to analysingthose problems encountered with in the actual telephone occupation forecasts during the period of lead development. It is based on various predicting methods used at home and abroad. Further, the modelstated below overcomes the shortcomings that conventional forecast models have so that it is characterizedby the applicable and scientific features suitable for making decision by means of computers.

关键词： s: telecommunications law forecasting system model