• 한국컴퓨터정보학회논문지
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• 제9권4호
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• pp.173-178
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• 2004

개방형 통신망에서 CVR, VBR, UBR, ABR과 같은 다양한 트래픽 관리 및 지연에 관한 연구가 진행되고 있고 특히 ATM망에서는 대역폭 확장 및 트래픽 관리를 통한 망의 효율적이며 유연한 품질 서비스를 제공한다. 이러한 품질 서비스를 제공하기 위하여 트래픽에 보안서비스가 제공되어야 하며 이에 대한 연구가 진행되고 있다. 본 논문에서는 ATM 보안 그룹에 들어오는 패킷들을 안정성 기준으로 평가하고 등급으로 분류하여 안전한 패킷은 통과시키고 비안전한 패킷은 폐기 또는 마크 패킷으로 통과 시킨다. 본 논문은 스위치에서 마크 패킷을 통과 시킬때 발생하는 패킷 지연에 관한 연구 및 시뮬레이션 시나리오를 제공한다.

• 대한수의학회지
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• 제28권2호
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• pp.405-408
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• 1988

The origin of Jindo dogs has been controversial. It has been informed by words of mouth that they are the offsprings of either the digs of Sung dynasty (960~1279 A.D.) in China or the Mongolian dogs. Some breeds of dogs in Japan now have almost same appearance as Jindo dogs. The authors reviewed the history of Japan and found that Korean hunting dogs were sent to Japan in early 5th century, which was before Sung dynasty of China. Dr. Jae-Keun Ryu of National Institute of Environmental Research has done some work on serums of dogs of both Korea and Japan; the results of his serological and molecular biological studies indicated that Korean dogs were sent to Japan 1,300~2,500 years ago. Jindo dogs appear to be the descendants of the dogs of the Stone Age. They have adapted themselves to the unfavorable environment of Jindo island so that they can maintain pure line-age and wild nature until today. It was concluded that they are Korean native dogs, not the offsprings of the dogs of Sung dynasty or the Mongolian dogs.

• 한국전자통신학회논문지
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• 제13권2호
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• pp.435-442
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• 2018

본 논문에서는 FPGA를 기반으로 Camera Link (Medium)를 제공하는 PCB 패턴 검출 시스템을 구현하였다. 시스템 구현을 위해 비전 라이브러리를 IP로 구현하여 고속으로 패턴 매칭을 할 수 있도록 하였다. 구현된 IP는 영상입력용 카메라링크 IP, 히스토그램 IP, VGA 제어 IP, 수직투영 IP 및 수평투영 IP가 있다. 디지털 카메라에서 고속으로 전송되는 영상을 처리하기 위해 Xilinx사의 Virtex-5 계열의 FPGA 칩을 사용하였다. 그래버 시스템 구현을 위해 RISC 구조의 CPU인 MicroBlaze를 사용하였으며, PC와의 연동을 위해 PCI Express를 사용하였으며, 영상의 처리결과는 컴퓨터의 모니터와 7인치 LCD에 표현하였다.

• Journal of Advanced Marine Engineering and Technology
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• 제28권4호
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• pp.667-674
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• 2004

This thesis is about the Impressed Current Cathodic Protection (ICCP) control and monitoring system. which brings protection against the corrosion of the ship's hull in the sea environments. The ICCP system is composed of a power supply. anode. reference electrode and controller. AC sources from the ship's generator are converted to DC sources in terms of power supply, and a protection current is sent to ship's hull though anode. The controller fully senses whether or not the detected potential is within a range of protection of ship's hull and then it is automatically controlled to increase or decrease the amount of protective current to be sent to the anode. The monitoring system with RS 232/485 communication is also studied in order to check the normal state of the system at a long period. because an operator does not always watch over this system and thus the system cannot operate well because of his or her negligent management. Since the vessel always navigates in the sea. an characteristics experiment of the ICCP system is conducted by introducing various corrosive environmental factors such as velocity, resistivity, dissolved oxygen, PH, temperature and contamination degree. These results must be referred to when the ICCP system is set up. In short. the ICCP is a multi-system for use on ships and on land structures because it includes a safety device. It is suggested that this system can accomodate a ship's automation and will be very useful.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집A
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• pp.1-6
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• 2000

FFP(Fitness For Purpose) type defect assessment methodologies based on ECA(Engineering Critical Analysis) have been established and are in use for the structural integrity evaluation of gas pipelines. ECA usually includes the fracture mechanics analysis, and it assumes that J-integral uniquely characterizes crack-tip stress-strain fields. However, it has been shown that it is not sufficient to characterize the crack-tip field under low levels of constraint with a single parameter. Since pipeline structures are made of ductile material, locally loaded in tension, cracks may experience low level of constraint, and therefore, J-dominance will be lost. For this reason, the level of constraint must be quantified to establish a precise assessment procedure for pipeline defects. The objective of this paper is to Investigate the fracture behavior of a crack in gas pipeline by quantifying the level of constraint. For this purpose, tensile tests and CTOD tests were performed at room temperature$(24^{\circ}C)$ and low temperature$(-40^{\circ}C)$ to obtain the material properties. J-Q analyses were performed for SENB and SENT specimens based on 2-D finite element analyses, in order to investigate the in-plane constraint effects on pipeline defects.

• 간호행정학회지
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• 제18권2호
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• pp.244-250
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• 2012

Purpose: The purpose of this study was to investigate the effect of a short message service intervention on adherence to maximal barrier precautions (MBP) and catheter-related blood stream infections. Method: The data were collected from March to September, 2008, at an 826-bed university-affiliated hospital in Daejeon. The study participants were 24 physicians who were inserting central catheters and 133 patients (control group 78 and intervention group 55) with central catheter insertions. The researcher sent the message (adherence to MBP and optimal recommendations) to each internal medicine doctor using the short message service (SMS) for cellular phones. Messages were sent monthly for 3 months. Data were analyzed by chi-square test and t-test using SPSS 12.0 windows program. Result: Adherence to maximal barrier precautions was significantly increased from 44.9% to 69.1% (p=.006) after the SMS intervention. But changes in the rate of CRBSI (catheter related blood stream infection) between the intervention group (1.89) and the control group (4.45) were not significant (p=.323). Conclusions: The results indicate that the SMS intervention is effective in increasing the adherence to maximal barrier precautions and the SMS intervention can be recommended for utilization in infection control nursing practice.

• Journal of Electrical Engineering and Technology
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• 제6권3호
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• pp.375-383
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• 2011

This paper describes a real-time hardware simulator for a grid-tied Permanent Magnet Synchronous Generator (PMSG) wind power system, which consists of an anemometer, a data logger, a motor-generator set with vector drive, and a back-to-back power converter with a digital signal processor (DSP) controller. The anemometer measures real wind speed, and the data is sent to the data logger to calculate the turbine torque. The calculated torque is sent to the vector drive for the induction motor after it is scaled down to the rated simulator power. The motor generates the mechanical power for the PMSG, and the generated electrical power is connected to the grid through a back-to-back converter. The generator-side converter in a back-to-back converter operates in current control mode to track the maximum power point at the given wind speed. The grid-side converter operates to control the direct current link voltage and to correct the power factor. The developed simulator can be used to analyze various mechanical and electrical characteristics of a grid-tied PMSG wind power system. It can also be utilized to educate students or engineers on the operation of grid-tied PMSG wind power system.

• 한국문헌정보학회지
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• 제32권1호
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• pp.7-26
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• 1998

이 연구에서는 타 도서관의 목록 데이터베이스를 탐색한 후 바로 원하는 자료를 요청할 수 있는 이용자 주도형 상호대차 모형을 제시하고, Z39.50 자료주문 확장서비스를 이용하는 상호대차 요청시스템을 구현하였다. 이 모형에서 이용자의 상호대차 요청은 Z39.50 확장서비스 요청 PDU를 통해 소속도서관으로 전달되며, 소속도서관과 자료의 소장도서관 사이의 상호대차 트랜잭션은 ILL 프로토콜을 이용하여 처리된다. 자료주문 확장서비스 요청 PDU의 파라미터로 ILL-REQUEST PDU를 포함시킴으로써 Z39.50 확장서비스와 ILL 프로토콜을 사용하는 두 단계의 요청과정을 효과적으로 연결할 수 있다.

• 한국통신학회논문지
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• 제37권4B호
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• pp.288-299
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• 2012

최근 모바일 클라우드 환경에서 공유되는 데이터의 기밀성과 유연성있는 접근제어를 보장하기 위해서 KP-ABE(Key Policy-Attribute Based Encryption)와 PRE(Proxy Re-Encryption)를 활용한 시스템 모델이 제안되었다. 그러나 기존 방식은 철회된 사용자와 클라우드 서버간의 공모 공격으로 데이터 기밀성을 침해하게 된다. 이러한 문제를 해결하기 위해서 제안 방식은 클라우드 서버에 저장되는 데이터 파일(data file)을 분산 저장하여 데이터 기밀성을 보장하고 비밀분산(Secret Sharing)를 통해서 프록시 재암호화키에 대한 변조 공격을 방지한다. 그리고 제안방식을 의료 환경에 적용한 프로토콜 모델을 구성한다.

• 통상정보연구
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• 제9권3호
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• pp.287-304
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• 2007

Determination of the time and place of dispatch and receipt of electronic messages is an important element of the operation of many rules of law, particularly the timing of formation of the contract. In this paper, I reviewed interpretation and application of time and place of dispatch and receipt of electronic records in electronic transactions under the UNCITRAL(United Nations Commission on International Trade Law) Model Law on Electronic Commerce, USA Uniform Electronic Transactions Act and Korea Electronic Transactions Act. Time of dispatch and time of receipt are effective when received. The sender has the burden to prove that the electronic record is sent successfully to the information process system of the recipient. Therefore, to safety electronic transactions, the sender needs to request a confirm notice for receipt to the recipient when the electronic record is sent like the provisions of UNCITRAL Model Law on Electronic Commerce and Korea Electronic Transactions Act. By requesting the above, the sender is able to take precautionary measures for damage according to the failure of dispatch and receipt of the electronic records.