• 한국신재생에너지학회:학술대회논문집
• /
• 한국신재생에너지학회 2006년도 춘계학술대회
• /
• pp.551-554
• /
• 2006

An inverter system which consists of three bi-directional buck-boost converters, is proposed for motor driving. Three phase sinusoidal output voltages can be generated by utilizing three buck-boost converters. The advantage of this scheme is that it does not require a separate DC-DC converter for motor driving, i.e. inverter function is combined into the three DC-DC converters. This topology is suitable for inverters for hybrid or fuel cell vehicles where DC link voltage is subject to change depending upon charging status or output power. So the proposed system is capable of driving motor at high speed. The converter system is controlled by PI controller and simulation results done by MATLAB SIMULINK are provided.Ҙ?⨀ሉȀ̀㘰々K䍄乍?ጊ츀Ѐ㔹〻Ԁ䭃䑎䴀

• Anatomy and Cell Biology
• /
• 제56권2호
• /
• pp.276-279
• /
• 2023

The arterial support of the liver is most commonly from the celiac trunk via the proper hepatic artery (PHA). The PHA divides into left and right branches: the right hepatic artery (RHA) supplies the right and caudate lobes while the left hepatic artery (LHA) supplies the left and quadrate lobes. Aberrant hepatic arteries are relatively common, and the most frequent contributors are the superior mesenteric artery and left gastric artery. Herein we present findings from postmortem dissection of an abdominal cavity that revealed a rare combination of reported variations. Specifically, this subject had three extrahepatic arteries - a replaced LHA (rLHA), a PHA, and a replaced RHA (rRHA). The rLHA originated from the left gastric and the rRHA originated from the superior mesenteric artery. Knowledge of these variations is important for surgical and radiological procedures to avoid complications during treatment and improve patient outcomes.

• 한국학교ㆍ지역보건교육학회지
• /
• 제1권1호
• /
• pp.95-106
• /
• 2000

The purpose of this study was to be of use for the preparation of more desirable sex education system at elementary school, by making content analysis of the current textbooks related to sex education and surveying what opinions the persons concerned had about it. The purpose of this study were as follows; Elementary school textbooks were analyzed to find out what kind of sex education was included in them. And questionnaires on how to improve school sex education content were prepared, by which 207 male and female teachers were surveyed in the city of Paju and Koyang, Kyonggi province. The conclusions were as follows; 1. Content Analysis of Textbook Sex Education The content related to sex education was relatively much included in textbooks of the right life, morality and physical education. Although morality was a subject to be instructed for the third-grade students or older, elementary school students virtually received sex education from the first grade, as the right life and the joyful life were a subject for the lower-grade students, and this met the goal of sex education or the need of the times. However, sex education content leaned heavily toward family, family life or parental love. There was no mutual complement among subjects, and no link among grades, either. 2. Teacher Opinion on Sex Education Content for Each Grade When the subjects were asked about if sex education content was appropriate for each grade, they answered 20 items should be more emphasized and 6 items might be left out. And there were 6 items regarded by them as one that should be rearranged in consideration of grade. 3. The Ideal Opinion of Sex Education Content The following model could be recommended for elementary school sex education, which was designed to meet the objectives of school sex education as much as possible and to offer a systematic link among grades, based on the findings by textbook analysis and Questionnaire survey, and on elementary school sex education materials recommended by the Ministry of Education: The content selected for the first grade of elementary school was my body, cleanness of genitals, male-female cooperation, and family cooperation. For the second grade, the selected content was male-female physical difference, male female psychological difference, parental and I(origin of a birth). For the third grade, the selected things were important a body(cleanness of genitals), birth of a life, and male-female comprehension and cooperation. For the fourth grade, the selected things were physical development, management of genitals, physiology and management of menstruation, propagation and growth of organism, concern for the other sex, comprehension of and cooperation with the other sex, and prevention of sexual violence. Four the fifth grade, the selected things were secondary sex characteristic, physiology and management of menstruation, operation for phimosis, understanding of seminal emission, structure and function of the genital organs, birth and growth of a baby, television/sex information, and mass communications/sex information. For the sixth grade, the selected things were secondary sex characteristic, understanding of seminal emission, male-female cooperation, male and female role, male-female manners, mass communications/sex information, family and family life. Finally, what should be taught in sex education must be studied constantly, as it should be revised or supplemented periodically, according to student's sexual maturity or social, cultural changes.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2005년도 ICCAS
• /
• pp.631-637
• /
• 2005

This paper presents a stiffness analysis method for a low-DOF parallel manipulator, which takes into account of elastic deformations of joints and links. A low-DOF parallel manipulator is defined as a spatial parallel manipulator which has less than six degrees of freedom. Differently from the case of a 6-DOF parallel manipulator, the serial chains in a low-DOF parallel manipulator are subject to constraint forces as well as actuation forces. The reaction forces due to actuations and constraints in each limb can be determined by making use of the theory of reciprocal screws. It is shown that the stiffness model of an F-DOF parallel manipulator consists of F springs related to the reciprocal screws of actuations and 6-F springs related to the reciprocal screws of constraints, which connect the moving platform to the fixed base in parallel. The $6{times}6$ stiffness matrix is derived, which is the sum of the stiffness matrices of actuations and constraints. The six spring constants can be precisely determined by modeling the compliance of joints and links in a serial chain as follows; the link can be considered as an Euler beam and the stiffness matrix of rotational or prismatic joint can be modeled as a $6{times}6$ diagonal matrix, where one diagonal element about the rotation axis or along the sliding direction is zero. By summing the elastic deformations in joints and links, the compliance matrix of a serial chain is obtained. Finally, applying the reciprocal screws to the compliance matrix of a serial chain, the compliance values of springs can be determined. As an example of explaining the procedure, the stiffness of the Tricept parallel manipulator has been analyzed.

• 정보보호학회논문지
• /
• 제29권5호
• /
• pp.1063-1075
• /
• 2019

최근 산업에서는 산업 자동화를 구축하여 효율적인 시스템 관리를 위해 WISN(Wireless Industrial Sensor Network)를 도입하고 있다. 무선센서를 도입하는 WISN는 도입하여 많은 엔지니어링 비용을 절감하고 공정 프로세서의 최적화를 이루어내면서 무선으로의 통신의 사용이 증가하고 있다. 산업용 무선 센서 네트워크에 대한 실증 연구는 활발하게 진행되고 있지만, 이에 대한 보안 연구는 적으며 그만큼 위협에 노출되어 있다. 뿐만 아니라 무선 통신프로토콜의 표준 자체의 문제점이 있을 경우 표준에 따라 인증된 기기 또한 문제점을 포함한 보안 위협이 따를 수 있다. 각 프로토콜의 표준에서는 보안키를 분배하기 위한 절차가 제시되어 있지 않거나 혹은 기기가 네트워크에 진입할 때 Global Data Link 키를 사용하여 보안에 취약한 문제점이 있었다. 본 논문에서는 표준에 기반하여 ISA 100.11a와 WirelessHART 프로토콜 스택에 따른 보안 기능과 위협에 대해 분석 표준 자체의 문제점을 제시하고 그에 따른 보안 요구 사항에 대해 제시한다.

• 한국실내디자인학회논문집
• /
• 제12호
• /
• pp.40-49
• /
• 1997

What's the direction of INTERIOR ARCHITECTURAL DESIGN in 21 Century High Tech\ulcorner The purpose of this research is to show not only practical use of Computer Graphic(CG) as simple tool function, but offering conversation with computer and other ways of method. When we consider poor CG market, investment on the research of VR(Virtual Reality) is the most urgent. The investment on VR will solve various problems. Firstly. It will solve the problems drived from Interior design process by making spatial images like reality. Secondly, It will solve high wages and financial difficulties caused by raise cost funds. Thirdly, It prevents in a road from foreign company that will bring enormous program, caused by opening the domestic market. Also, It help interior designer check in advance the problems in constructure through showing him a supposed imagination including the system and location of equipments. But it is reality that even ordinary American can't offer VR(Virtual Reality) System. We should have noted that it is normal to spend 10 billion won for such presentation as Model House in the large corporation. We must acknowledge that it is such a waist of money nationally. Therefore, investment on CG & VR System is essential in order to save cost more effective presentation & interior design. We will see great result within a year. As we can see, there is huge area we have make develop. One of them is specific technical plan on VR System and study of flow chart. We close with simple methodological way to use VR System and will study Computer System. Which is fitting to CG that we have to solve the link of hardware and software on VR System\ulcorner We know from the cases in other countries that continuous research on this subject has great value for Interior Architectural Design and its effective use. When we try hard not only for methodological use but practical use, the purpose of CG and VR System will be a factor to contribute on this subject for better Interior design & presentation.

• 한국실내디자인학회논문집
• /
• 제24권1호
• /
• pp.160-168
• /
• 2015

The subject of this research is to analyze the design characteristics of outdoor spaces in Good Design awarded apartment complexes in the past decade. The results are as follows. First, the overall outdoor space design theme, one of the conceptual elements, is focused on both 'nature' and 'story of various subject' that are similar to each other. Second, the case study object with the visual openness, which is secured between apartment blocks, is shown frequently in case box-shaped apartment blocks are arranged in a row. However, in case of Y-shaped block arrangement, the visual openness secured within an apartment complex is considered more important. Third, according to the result of circulation/ inner path element, the most frequently appeared inner path form is a grid pattern with straight path emphasis. While apartment complexes with the parking lot on the ground are only 3 out of 18 cases, it with circulation path for vehicle on the ground level are over 61%. Fourthly, the design characteristic of social space of physical outdoor design appears to be 'central link facility type'. In this case, the central community facilities are more likely to be combined with various functions, such as green, water, and social connection. Fifthly, in case of natural space, most of the apartment cases are shown over 45% green area ratio with wide green and water space provision. Especially, the differentiation is to provide the space where can stimulate a resident's participation.

• 정보관리학회지
• /
• 제24권4호
• /
• pp.73-96
• /
• 2007

이 연구에서는 웹과 학술지를 통한 학술 커뮤니케이션의 특성을 각각 분석하고, 웹상에서의 학술 커뮤니케이션 패턴이 학문 분야에 따라 어떤 차이를 보이는지 비교하였다. 경제학과 컴퓨터공학-정보시스템분야에서 키워드를 추출하여 이와 관련된 학술적 웹페이지와 학술지 논문을 수집하였고, 이를 학술적 웹페이지의 특성, 웹페이지 동시링크와 학술지 논문 동시인용 데이터의 다차원척도(MDS) 분석, 시간의 흐름에 따른 학술 활동의 변화 등 세 가지 측면에서 분석하였다. 분석결과, 웹과 학술지를 통한 학술 커뮤니케이션에는 공통점과 차이점이 나타났으며, 이런 현상은 두 학문 분야에서 모두 확인되었다. 그리고 웹을 통한 학술 커뮤니케이션의 경우 같은 학문 분야 내의 세부 주제에 따라서 고유한 특성이 나타나는 것을 볼 수 있었다.

• 한국통신학회논문지
• /
• 제22권9호
• /
• pp.1933-1940
• /
• 1997

본 논문은 4개의 생체에서 계측된 생체신호를 처리할 수 있는 기능을 가진 시스템을 CMOS 기술을 사용하여 단일칩화하여 포토다이오드와 LED의 적외선을 전송매체로 하여 외부 관측시스템으로 미소 생체신호를 송수신하는 광전송시스템을 개발하였다. 개발된 시스템은 전원전압에 대한 의존성을 감소시키고, 연속된 4 생체 4 채널 텔레미터를 구현하기 위해 적외선 통신이 가능한 강제 동기식 방법을 제안하였다. $5.1{\times}5.1mm^2$ 크기의 신호처리용 IC는 외부 명령신호 수신, 내부 블럭 초기화, 생체 선택신호 해독, 생체신호 시분할 다중화, 외부 시스템에 데이터 전송 및 자동 전원차단 등의 기능이 있다. 또한 본 논문에서 개발된 생체신호처리용 IC 검증을 위해 외부관측시스템을 상용 IC를 사용해 조립후 심전도를 송신해 외부관측시스템에서 수신하는 광전송시스템을 구현하였다.

• 경영과정보연구
• /
• 제31권4호
• /
• pp.83-108
• /
• 2012

광고공모전에 대한 학생들의 관심이 매우 높아 수업과의 연계 속에서 진행되는 공모전이 있을 정도이다. 기업들 역시 이러한 공모전을 통해 기업 활동에 도움을 받고 있는 입장이지만, 아직까지 광고나 마케팅커뮤니케이션 관련 공모전을 주제로 하는 학술적인 연구는 연구 현재의 시점에서 5편에 불과하다. 이들의 연구 내용을 분석한 결과 주로 공모전 참여 활성화 측면, 기업 윤리적인 측면, 산학협력 측면 등에서 활용 가치를 찾을 수 있었다. 하지만 이것은 여전히 불충분 하며 때문에 기존 연구들이 제시한 시사점들에 대한 분석을 토대로 후속 연구의 필요성이 강력히 제기되고 있다. 후속 연구가 필요하다고 제시하는 분야는 투자 대비 광고공모전의 효과 분석, 선행 연구들에 대해 면밀한 실험 연구를 통한 이론적 정립, 공모전 형태에 따른 비교 연구, 개인 성향이 공모전 주최 기업의 이미지에 미치는 영향 등이며, 이 밖에도 기업의 필요와 관련되었거나 학생들의 필요 충족과 관련하여 보다 많은 연구의 필요성을 제기한다.