• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 D
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• pp.2126-2128
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• 2001

This paper suggests that the immune network algorithm based on fuzzy set can effectively be used in tuning of a PID controller for multivariable process or nonlinear process. The artificial immune network always has a new parallel decentralized processing mechanism for various situations, since antibodies communicate to each other among different species of antibodies/B-cells through the stimulation and suppression chains among antibodies that from a large-scaled network. In addition to that, the structure of the network is not fixed, but varies continuously. On the other hand, a number of tuning technologies have been considered for the tuning of a PID controller. As a less common method, the fuzzy and neural network or its combined techniques are applied. However, in the case of the latter, yet, it is not applied in the practical field, in the former, a higher experience and technology is required during tuning procedure. Along with these, this paper used the fuzzy set in order that the stimulation and suppression relationship between antibody and antigen can be more adaptable controlled against the external condition, including noise or disturbance of plant. The immune network based on fuzzy set suggested here is applied for the PID controller tuning of multivariable process with two inputs and one output and is simulated.

• 한국통신학회논문지
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• 제32권5B호
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• pp.277-285
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• 2007

본 논문에서는 2003년 국내 뿐만 아니라 전세계의 인터넷망에서의 심각한 소통장애를 일으켰던 슬래머 웜 보안공격의 전파과정에 대한 새로운 통신망 모델을 제시하고 NS-2를 이용한 시뮬레이터를 구현하여 웜 보안공격에 의한 전파과정을 분석하였다. 기존 DN-AN모델을 Abstract network-Abstract network(AN-AN)모델로 추상화함으로써 국내 뿐만 아니라 전 세계의 수많은 호스트를 대상으로 한 대규모 인터넷망에 대하여 최초의 웜 패킷이 국내의 인터넷 국제관문국으로 유입된 시점부터 국내의 망이 포화되는 전 과정을 시간대별로 분석할 수 있는 NS-2용 시뮬레이터를 구현하였다. 또한 구현된 시뮬레이터는 감염된 국내의 호스트에 의해 국외의 호스트를 감염시키는 과정도 분석 가능하였다. 시뮬레이션 결과 290초만에 8,848개의 국내 호스트가 감염되었고, 308초만에 66,152개의 국외 호스트가 감염되었다. 또한 공격시 수행되는 웜 감염 전파과정에 의해 국내로 유입되거나 국외로 유출되는 웜 감염패킷들은 국제관문국에서 각각 154초와 135초내에 포화됨을 알 수 있었다.

• 지식경영연구
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• 제24권3호
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• pp.195-215
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• 2023

통신사업자는 기본적으로 투자해서 얻을 수 있는 미래 수익이 크면 투자를 단행한다. 그동안의 통신 시장은 통신사업자가 네트워크 투자를 통해 경쟁우위를 확보하여 가입자와 매출을 증가시켜 수익을 얻는 것이 가능하였다. 그러나 융합과 디지털 전환이라는 거대한 변화 속에 네트워크 투자가 곧 수익으로 이어지는 단순한 구조는 점점 깨지고 있다. 과거에는 네트워크라는 인프라를 보유한 통신사업자 간에만 경쟁이 이루어졌으나, 이제는 경쟁의 축이 다변화되면서 단순히 인프라 고도화만으로는 수익 증가를 담보하기 어려워졌다. 디지털융합 시대의 플랫폼 경제체제에서는 네트워크가 없는 플랫폼 사업자가 경쟁우위를 점하고 수익을 가져가는 구조가 형성되고 있다. 이에 따라 기존 통신사업자의 네트워크 투자유인이 감소할 수밖에 없는 상황이다. 본 논문은 디지털 경제 시대에 통신 네트워크 투자 촉진을 위한 정책 방안을 모색하는 데 목적이 있다. 이를 위해 사업자의 네트워크 투자에 영향을 미치는 요소와 영향의 방향 등을 분석하고 네트워크 고도화를 위한 합리적 대안을 파악한 후, 전문가 설문 및 다기준의사결정(Analytic Hierarchy Process, AHP; Analytic Network Process, ANP) 분석을 통해 정책적 시사점 및 우선순위를 도출한다. 전문가들을 대상으로 한 AHP/ANP 분석 결과에 따르면 공공의 개입에 대해서는 다소 부정적인 시각을 갖고 있으며 새로운 경쟁의 축을 도입하는 것을 더 지지하고 있다. 다만 국민의 보편적 네트워크 접근권 보장 및 확대를 위해서는 비경제적 지역을 중심으로 공공의 역할 확대를 검토할 필요는 있다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.917-921
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• 2004

Principle of mailing list was distributed messages to all subscribers in one time. But mailing list operation has constructed a network traffic problem. Because mailing list manager distributed mails without concentrate on subscriber network. If our network has many of subscribers, there will be redundant data in traffic channel. Submailing list has purpose to reduce problems. Analyses of mailing list characteristic in electronic mail were a feature of submailing list system, which manage by human hand (Network Administrator). That will cause trouble for network traffic if Network Administrator could not seek for mailing list characteristic from e-mails in due time. This article will present ideas and recognize methodology for automatic working in submailing list system. Recognize step begin with capture process, which use to trap e-mail information from transfer channel. Next process is preparing raw data into recognition format. Then the third one is recognize part and find out confidential factor. The last process is make decision and determine which electronic mail has properties of mailing list characteristic. Afterward deliver result to submailing list for carry on.

• 한국생산제조학회지
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• 제8권5호
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• pp.70-75
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• 1999

Adaptive control in the robotic GMA(Gas Metal Arc) welding is employed to monitor the information about weld characteristics and process paramters as well as modification of those parameters to hold weld quality within the acceptable limits. Typical characteristics are the bead geometry composition micrrostructure appearance and process parameters which govern the quality of the final weld. The main objectives of this paper are to realize the mapping characteristicso f penetration through the learning. After learning the neural network can predict the pene-traition desired from the learning mapping characteristic. The design parameters of the neural network estimator(the number of hidden layers and the number of nodes in a layer) were chosen from an error analysis. partial-penetration single-pass bead-on-plate welds were fabricated in 12mm mild steel plates in order to verify the performance of the neural network estimator. The experimental results show that the proposed neural network estimator can predict the penetration with reasonable accuracy and gurarantee the uniform weld quality.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2000년도 특별강연 및 춘계학술발표대회 개요집
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• pp.251-255
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• 2000

Recently, the improvement of computer capacities and artificial intelligence ware caused to employ for prediction of residual stresses and strength evaluation. There are a lot of researches regarding the measurement and prediction of residual stresses for weldment using a neural network in the advanced countries, but in our country, a neural network as a technical part, has only been used on the possibilities of employment for welding area. Furthermore, the relationship between residual stress and process parameters using a neural network was wholly lacking. Therefore development of a new technical method for the optimized process parameters on the reduction of residual stress and applyment of real-time production line should be developed. The objectives of this paper is to measure the residual stress of butt welded specimen using strain gage sectioning method and to apply them to a neural network for prediction of residual stresses on a given process parameter. Also, the assessment of the developed system using a neural network was carried out

• 한국기계가공학회지
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• 제14권3호
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• pp.65-73
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• 2015

This paper presents a method of predicting the machining parameters on the turning process of low carbon steel using a neural network with back propagation (BP) and particle swarm optimization (PSO). Cutting speed, feed rate, and depth of cut are used as input variables, while surface roughness and electric current consumption are used as output variables. The data from experiments are used to train the neural network that uses BP and PSO to update the weights in the neural network. After training, the neural network model is run using test data, and the results using BP and PSO are compared with each other.

• 한국공작기계학회논문집
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• 제17권5호
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• pp.123-130
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• 2008

In order to clarify detailed mechanism of the flexible disk grinding system, workpiece length was introduced and its performance was evaluated. Flat zone ratio increased as the workpiece length increased. Increasing wheel speed and depth of cut also enhanced process performance by producing larger flat zone ratio. Neural network system was successfully applied to predict minimum depth of engagement and flat zone ratio. An additional input parameter as workpiece length to the neural network system enhanced the prediction performance by reducing error rate. By rearranging the Input combinations to the network, the workpiece length was precisely predicted with the prediction error rate lower than 2.8% depending on the network structure.

• 한국멀티미디어학회논문지
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• 제17권5호
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• pp.590-600
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• 2014

In the wireless sensor network environment, clustering scheme has a problem that a large amount of energy is unnecessarily consumed because of frequently occurred entire re-clustering process. Some of the studies were attempted to improve the network performance by getting rid of the entire network setup process. However, removing the setup process is not worthy. Because entire network setup relieves the burden of some sensor nodes. The primary aim of our scheme is to cut down the energy consumption through minimizing entire setup processes which occurred unnecessarily. Thus, we suggest a re-clustering scheme that considers event detection, transmitting energy, and the load on the nodes. According to the result of performance analysis, our scheme reduces energy consumption of nodes, prolongs the network lifetime, and shows higher data collection rate and higher data accuracy than the existing schemes.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 심포지엄 논문집 정보 및 제어부문
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• pp.258-260
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• 2006

In this paper, we designed a embedded system that will perform a primary role of Tangible Space implementation. This hardware includes function of image capture through camera interface, image process and sending off image information by LAN (local area network) or WLAN(wireless local area network). We define this hardware as a network based Visual Agent Platform for Tangible Space