• Proceedings of the Korean Information Science Society Conference
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• 2004.10c
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• pp.70-72
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• 2004

본 논문은 NS-2 에서의 새로운 네트워크 요소 모듈 개발에 관한 연구를 목적으로 한다. 현재 대부분의 새로운 네트워크 요소들은 경제적인 이유와 네트워크의 환경적인 제약으로 인해서 시뮬레이터 환경에서 실험 되어지고 컴퓨터 공학에서 가장 많이 알려진 시뮬레이션툴 중의 하나로 NS-2 가 많이 사용되어 지고 있다 이러한 NS-2 는 Otcl 이라는 MIT 에서 개발한 언어와 C++ 가 상호 연동 되어져서 이벤트 처리 부분은 OTcl 이 담당하고 패킷 처리 부분은 C++가 담당 하고 있지만 새로운 네트워크 요소를 추가 하는 부분을 이해 하기에는 현재 공개된 문서 만으로는 이해하기 어려운 부분이 많다. 본 논문에서는 NS-2 에 새로운 네트워크 요소를 추가 하는대 있어서 필요한 NS-2 의 기술적인 부분을 설명함을 목적으로 하였다.

• Journal of the Korean Society for Railway
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• v.6 no.2
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• pp.81-86
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• 2003

This study proposes the neural network simulator for the integrity evaluation of weld zone in railway rails. For these purposes, the ultrasonic signals for defects(crack) of weld zone in frames are acquired in the type of time series data and echo strength. The detection of the natural defects in railway truck is performed using the characteristics of echodynamic pattern in ultrasonic signal. And then their applications evaluated feature extraction based on the time-frequency-attractor domain(peak to peak, rise time, rise slope, fall time, fall slope, pulse duration, power spectrum, and bandwidth) and attractor characteristics (fractal dimension and attractor quadrant) etc. The constructed neural network simulator agrees fairly well with the measured results of test block(defect location, beam propagation distance, echo strength, etc). The Proposed neural network simulator in this study can be used for the integrity evaluation of weld zone in railway rails.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.370-371
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• 2011

This paper proposed an under-voltage relay algorithm module for a network based protective relay simulator. The simulation system is based on the client-server paradigm. The relaying simulator which consists of server-side relay models and user interface provides network-based simulation environment for a variety of protective relaying algorithms. The performance of the relay algorithm was verified by comparing the results of under-voltage relay algorithm in the simulator with the results of the C language implementation.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.6
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• pp.1503-1513
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• 1998

This paper is related to a performance analysis of B-NT system, which is essential compositional equipment of B-ISDN access network. A simulator enabling performance analysis according to the change of network configuration topology and the change of user traffic is developed in this study. The developed B-NT, system simulator consists of graphic user interface module, simulation program automatic generator module, and B-NT system model library module. As examples of the results of performance analysis using the simulator, end-to-end user cell transmission delay time, queueing delay time in each system, and cell loss rate in the head node switch are presented. The simulator developed in this paper can be utilized in determining the network topology of B-NT system.

• Journal of the Korea Society for Simulation
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• v.8 no.2
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• pp.45-56
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• 1999

It is necessary that we should control the traffic to not only efficiently use the rich bandwidth of ATM network but also satisfy the users various requirements for service quality. However, it is very difficult to decide which control mechanism would be applied in real network because there are various types of ATM traffic and traffic control mechanisms. In this paper, a smart simulator is developed ot analyze the performance of a UPC(Usage Parameter Control) mechanism which is a typical traffic control mechanism. The simulator consists of a user interface that supports a menu-driven input form and a simulation program that is executed with the users input parameters. Especially, the simulator establishes more powerful and flexible simulation environment since it supports a more complex simulation applying various source traffic to several different UPC mechanisms at the same time and allows an arbitrary user-defined traffic in addition to some well-known traffic.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.05a
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• pp.845-848
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• 2008

In case of application test in wireless sensor network, there are many difficulties in power supplying to wireless sensor node, installing and deploying of sensor nodes, maintaining and debugging. For efficient development and maintenance of wireless sensor network-based application, a simulator is essentially needed. However, the existing wireless sensor network simulators are focused to distribution of MAC address, routing, power management, it is not suitable to test the function of application in host which processes message through sink node. In this paper, we designed and implemented a log-based simulator for application running in host connected sink node.

• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.488-491
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• 1997

The PMGS(Plant Model Generating System) was developed based on modular modeling method and fluid network calculation concept. Fluid network calculation is used as a method of real-time computation of fluid network, and the module which has a topology with node and branch is defined to take advantages of modular modeling. Also, the database which have a shared memory as an instance is designed to manage simulation data in real-time. The applicability of the PMGS was examined implementing the HRSG(Heat Recovery Steam Generator) control logic on DCS.

• Proceedings of the KIEE Conference
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• 1998.11b
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• pp.637-639
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• 1998

Educational software tends to be monotonous without the interaction between instructors and students. An unidirectional teaching system can't overcome these barriers because the learning process is monotonous without the bidirectional communication. The advanced network system can solve these problems. In this study, a bidirectional microprocessor simulator is developed and a new teaching model is proposed using the simulator. It was named JMPS (Java Microprocessor Simulator), which is a software to teach the microprocessor principles and applications. It has two advantages. First, it can teach the principles and applications of microprocessor effectively. Second, it runs on Internet and provides easy communication between a teacher and students.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.10
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• pp.119-128
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• 2003

The rapid increase of Internet users, diversity of application services, high speed data transmission, and extension of application areas have resulted in exponential growth of Internet traffic. In order to satisfy the increasing demand of bandwidth, the MPλS protocol, which is based on MPLS for efficient integration of WDM and IP protocols, has been suggested by IETF. In this paper, we present an MPλS simulator which enables to simulate various MPλS function such as optical crossconnect (OXC), multi-wavelength links, routing and wavelength assignment(RWA), and MPλS signaling and control. The simulator is developed based on the ns-2, an widely used multi-protocol network simulator. The function of the simulator is validated by running many simulation based on various scenarios and performance measures such as throughput and blocking probability. The simulator could be widely utilized for validation of proposed protocols before developing real optical network systems.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.11 no.2
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• pp.108-121
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• 1986

In this paper, the development of a simulator for the performance estimation and parameter optimization of an integrates voice/data packet communication network is described. The simulator implemented is capable of simulating the integrated voice/data network that handles packet voice terminals as well as data terminals and hosts operating under standard CCITT protocols. Of the three descrete event simulation approaches presently known, the process interaction method has been chose. With this approach one can implement a simulator that is related most Closely with the real system. The simulator has been implemented in PL/I and GPSS simulation languages, resulting in a software package of about 4,000 lines. To reduce the computer run time of the simulator, we have used a method of reducing conditional events based on a GPSS LINK block. We describe various aspects of the simulation model developed. We then investigate the performance of a 7-node network using the simulator, and present the results. For validation of the simulator developed, we construct a simulation model for a simple voice/ data multiplexer, and compare the results of simulation with those of an analytical model.