• Proceedings of the Korea Information Processing Society Conference
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• 2003.11a
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• pp.385-388
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• 2003

인터넷 인구의 폭주로 트래픽을 줄이려는 노력이 일고 있는 가운데, 우리는 기존에 웹 서버의 성능를 리눅스 커널 단에서 향상시키는 방법을 제안하였다. 사용자 영역의 스레드를 사용하지 않고 커널 영역의 스레드를 사용하고 CPU 개수와 동일한 스레드만 사용함으로서 스레드간의 컨텍스트 스위칭과 시스템 콜 사용의 오버헤드를 줄일수 있었다. 이번에는 이 구조를 CPN(Coloured Petri-Net)을 사용하여 논리적으로 분해하고 그 동작특성을 이해하여 모델링과 실제 데이터를 비교함으로서 프로그램 동작에 관한 논리적 문제점을 발견할 수 있고, 동작특성의 시간특성을 알 수 있다.

• Information and Communications Magazine
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• v.16 no.10
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• pp.125-136
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• 1999

ADSL은 일반 가정이나 SOHO에서 Internet access나 Remote LAN Access와 같은 application을 대상으로 사용하기에 적합하다. 제 2장에서는 CPN에서의 configuration, usage scenario를 알아보고 splitter configuration들과 PDN, SM, TE간의 interface가 어떻게 정의되는가를 살펴보았다. 제 3장에서는 central office의 configuration을 간단히 살펴보고, DSLAM 및 service provider network의 requirement들을 알아보았다. 제 4장에서는 원활한 network adaptation 및 service를 위한 Frame based 및 ATM based ADSL architecture들에 대해 언급하고 가능한 protocol stacks들에 대해 간단히 알아보았다. 또한 home network이나 corporate network에서 필요한 tunneling protocol이나 firewall의 구현가능성도 검토하였다. 현재 이러한 내용들이 ADSL Forum에서 활발히 논의되고 있으나, UADSL을 비롯한 ADSL의 대규모 설치에 따른 field trial 및 service를 통해 장단점이 검증될 것으로 보이며 따라서 앞으로 $1\sim2$년 후에나 좀더 효율적인 ADSL architecture, interface 및 protocol이 표준모델로 정착될 것으로 보인다.

• Journal of Biomedical Engineering Research
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• v.17 no.3
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• pp.395-401
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• 1996

In this paper a new neural network model, time delayed counterpropagation neural networks (TDCPN) which have high recognition rate and short total learning time, is proposed for electromyogram(EMG) recognition. Signals the proposed model increases the recognition rates after learned the regional temporal correlation of patterns using time delay properties in input layer, and decreases the learning time by using winner-takes-all learning rule. The ouotar learning rule is put at the output layer so that the input pattern is able to map a desired output. We test the performance of this model with EMG signals collected from a normal subject. Experimental results show that the recognition rates of the suggested model is better and the learning time is shorter than those of TDNN and CPN.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.3
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• pp.18-27
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• 1996

By integrating WDM to OPS unit which plays an improtant role for the reliability of CPN, we made it possible to provide CATV, VOD, and high-speed data services simultaneously and to meet easily the requirements for new services in the future. For the design of optimal system, the link analysis of power budget has been perfomred. Also, the prototyped system has been tested with STM-1 level signals to confirm functions such as transmission, distribution, and protection. The results proved that when occurred out-of-order or recovery of ONU, the system did the pertinent switching with minimum loss for high-speed data services. Also for video distribution services, the system has distributed STM-1 level signals sucessfully.

• Proceedings of the KIEE Conference
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• 1995.07b
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• pp.465-467
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• 1995

High impedance fault can not be easily detected by conventional method. But if it would not be detected and cleared quickly, it can result in fires, and electric shock. In this paper, ANN, which has learning capability, is used for high impedance fault detection. The potential of the neural network approach is demonstrated by simulation using KEPCO's measured data. Among ANN models used in this paper, CPN shows better result than BPN in respect of convergence and reliability.

• Journal of the Optical Society of Korea
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• v.11 no.3
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• pp.101-107
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• 2007

In this paper, we have presented the results of Wavelength Division Multiplexing-Passive Optical Network (WDM-PON) based fiber-to-the-home (FTTH) field trial test which was held in the city of Gwangju. We have implemented an injection locked Fabry-Perot Laser Diode (FP-LD) based WDM-PON system and reliably delivered Internet Protocol TV (IP-TV), networked Personal Video Recorder (N-PVR), High-Definition Video on Demand (HD-VoD), Education on Demand (EoD) and Internet service as FTTH service through the system during the field trial test. We have also verified that the WDM-PON system worked well to provide quality of service (QoS) guaranteed 100Mbps bandwidth per subscriber. Furthermore, we have presented network designing issues in Outside Plant (OSP) and Customer Premises Network (CPN) that should be overcome to efficiently deploy FTTH service. Finally, based on the field trial test results, we proposed FTTH service deployment strategies.

• Proceedings of the IEEK Conference
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• 2000.07b
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• pp.661-664
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• 2000

A workflow expresses the How of persons and things related to a business. To improve efficiency of a business, it is important to grasp and evaluate the actual situation of the current business. Till now, researches on workflows have been done almost on once business and these results can not be simply applied to food business. Besides, it is also important how to evaluate a food business workflow with a specific standard. In this paper, we propose a modeling method of food business by using hierarchical Petri net. Then we propose a concept, called throughput, as a standard to evaluate the workflows. Finally we show a method how to compute throughput and meanwhile apply a Petri net tool, Design/CPN, to do simulation of computing throughput. Our simulation result shows the modeling method and computation method of throughput are reasonable and useful.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.9 no.1
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• pp.13-18
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• 2010

As the importance of non-functional requirements has increased, many researchers have become interested in the software development process for non-functional requirements including the notation, modeling, and assessment of non-functional requirements. However, the characteristics of non-functional requirements are so sophisticated and there are many topics which have not been solved until now. In order to address one of the unsolved problems, we propose a systematic software development process to support the management of non-functional requirements. The process consists of six steps, each of which is composed of detailed activities. Using the proposed process, the non-functional requirements can be managed and modeled more effectively and systematically than previous ones.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.19 no.3
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• pp.253-270
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• 2015

Two major simultaneous attack strategies have been introduced, as one of cooperative attack of multiple missiles. One strategy is an undesignated time attack, in which the missiles communicate among themselves to synchronize the arrival times by reducing the mutual differences of times-to-go of multiple missiles during the homing. The other is a designated time attack, in which a common impact time is commanded to all members in advance, and thereafter each missile tries to home on the target on time independently. For this individual homing, Impact-Time-Control Guidance (ITCG) law is required. After introducing cooperative proportional navigation (CPN) for the first strategy, this article presents a new closed-form ITCG guidance solution for the second strategy. It is based on the linear formulation, employing base trajectories driven by PNG with various navigation constants. Nonlinear simulation of several engagement situations demonstrates the performance and feasibility of the proposed ITCG law.

• Clinical Psychopharmacology and Neuroscience
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• v.16 no.4
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• pp.501-504
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• 2018

Autoimmune hemolytic anemia is a disease characterized with destruction of erythrocytes as a result of antibody produce against patient's own erythrocytes and anemia. Autoimmune hemolytic anemia can be roughly stratified into two groups according to serological features and secondary causes including drugs induced hemolytic anemia. Drugs induced autoimmune hemolytic anemia is very rare in pediatric patients. Even though hematological side effects such as leucopenia, agranulocytosis, eosinophilia, thrombocytopenic purpura and aplastic anemia might occur due to psychotropic drug use; to the best of our knowledge there is no autoimmune hemolytic anemia case due to quetiapine, an atypical antipsychotics, in literature. We hereby describe the first child case of autoimmune hemolytic anemia during quetiapine treatment.We also are pointing out that one should keep in mind serious hematological side effects with atypical antipsychotic drug use with this case report.