• 제목/요약/키워드: Various

검색결과 148,263건 처리시간 0.097초

다양한 형태의 통신망 성능 분석을 위한 시뮬레이션 도구의 개발 (Development of a simulator for the performance evaluation of various types of communication networks)

  • 윤복식
    • 산업공학
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    • 제9권3호
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    • pp.157-167
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    • 1996
  • Due to the drastic technological innovation and introduction of various kinds, of new communication services, the structure and operation of communication networks are becoming complicated and diversified more and more. Accordingly, the necessity of flexible simulation tools which can be utilized for various performance evaluation jobs in various types of communication networks is growing. In this article, various existing simulation tools are briefly surveyed and the requirements for the simulator dedicated for the performance evaluation of communication networks are discussed. Then, a strategy to develop a simulator dedicated for the performance evaluation of communication networks is proposed. Our approach is based on the prototyping strategy, in which a relatively simple prototype structure is developed first and more functions are added whenever necessary. By following this strategy, a simulator can be developed and evolved in a timely manner at a relatively small cost.

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금속입자가 전도성 잉크의 전도도에 미치는 영향 (Effect of Metal Powders on the Conductivity of Conductive Inks)

  • 권두효;정태의;김남수;한국남
    • 한국공작기계학회논문집
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    • 제17권2호
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    • pp.97-103
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    • 2008
  • In this investigation, conductivity of conductive inks was measured. A particular attention has been given to the effect of metal powders with various conductivity on the overall conductivity of the bulk ink. The conductivity of various solutions simulating conductive inks consisting of copper and silver was measured and the results have been discussed in relation to various applications of conductive inks in practice. A conductivity model simulating systems consisting of various materials has been introduced and the results were discussed. Materials of good conductivity are adversely affected by mixing with materials of poor conductivity simply through serial connection. However, parallel connection has rather little effect on the overall conductivity. The practical implication of various mixtures of materials on conductive inks has been discussed.

JPEG 재압축이 컬러 이미지 품질에 미치는 영향에 관한 연구 (A study on the effect of JPEG recompression with the color image quality)

  • 이성형;조가람;구철희
    • 한국인쇄학회지
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    • 제18권2호
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    • pp.55-68
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    • 2000
  • Joint photographic experts group (JPEG) is a standard still-image compression technique, established by the international organization for standardization (ISO) and international telecommunication standardization sector (ITUT). The standard is intended to be utilized in the various kinds of color still imaging systems as a standard color image coding format. Because JPEG is a lossy compression, the decompressed image pixel values are not the same as the value before compression. Various distortions of JPEG compression and JPEG recompression has been reported in various papers. The Image compressed by JPEG is often recompressed by same type compression method in JPEG. In general, JPEG is a lossy compression and the quality of compressed image is predicted that is varied in according to recompression Q-factor. In this paper, four difference color samples(photo image, gradient image, gradient image, vector drawing image, text image) were compressed in according to various Q-factor, and then the compressed images were recompressed according to various Q-factor once again. As the result, this paper evaluate the variation of image quality and file size in JPEG recompression and recommed the optimum recompression factor.

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RFID 시스템에서 DoS 공격을 포함한 다양한 공격에 대처하는 인증 기법 (An Authentication Scheme against Various Attacks including DoS Attack in RFID System)

  • 이규환;김재현
    • 한국정보통신설비학회:학술대회논문집
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    • 한국정보통신설비학회 2008년도 정보통신설비 학술대회
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    • pp.146-149
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    • 2008
  • The RFID system is very useful in various fields such as the distribution industry and the management of the material, etc. However, the RFID system suffers from various attacks since it does not have a complete authentication protocol. Therefore, this paper propose the authentication protocol that used key server to resist various attacks including DoS(Denial of Service) attack. For easy implementation, the proposed protocol also uses CRC, RN16 generation function existing in EPCglobal class 1 gen2 protocol. This paper performed security analysis to prove that the proposed protocol is resistant to various attacks. The analytical results showed that the proposed protocol offered a secure RFID system.

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퍼스널 로봇 미들웨어를 위한 CAN(Controller Area Network) Protocol (Controller Area Network (CAN) Protocol for Personal Robot Middleware)

  • 박태규;;박홍성
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 심포지엄 논문집 정보 및 제어부문
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    • pp.80-82
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    • 2004
  • Personal robot consist of various modules that have independent functions. Because personal robot has requirement that support various construction for user's tendency. Therefore, Middleware mechanism at support not only personal robot's main functional element but also embedded modules functional elements is required. Each module have various heterogeneous network interfaces and variable services and variables. Therefore, Middleware must support these various network interfaces. This paper, pointed in Controller Area Network(CAN) inreface that usually used in embedded system for control. For connect various heterogeneous network interfaces (Ethernet, RS232 etc..), it is necessary to modify bagic CAN frame format. And also make some kind of BUS topology for CAN network.

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단체급식소에서 제공되는 시금치 나물과 깻잎 나물의 생산단계 및 보관단계에 따른 리보플라빈 함량 변화(II) (Changes in the Riboflavin Content of Spinach Salad and Sesame Leaf Salad with Various Cooking and Holding Process in Foodservice Institutions)

  • 김혜영;박화연
    • 한국식품조리과학회지
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    • 제20권1호
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    • pp.34-41
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    • 2004
  • The retention rate of riboflavin in two cooked vegetable salads (spinach salad and sesame leaf salad) were examined at every cooking stage, holding temperature and holding time, with various cooking methods, and a better food preparation method developed. The riboflavin contents of the samples were analyzed by HPLC, with fluoresence detection. The changes in the pH and water contents of the samples were measured during the holding stage at various temperatures and times. There were significant differences in the riboflavin contents during the various preparation and cooking processes, such as trimming, washing, boiling and parching etc. The retention rates of the riboflavin with the various holding methods and cooking temperature were also significantly different. The boiling process caused large losses of riboflavin: in the cases of spinach salad and sesame leaf salad these were 78% and 52% respectively. The pH and water contents showed faster change during 0-6 hours than during 6-12 hours.

Modified Wilkinson Power Divider Using Transmission Lines for Various Terminated Impedances and an Arbitrary Power Ratio

  • Yoon, Young-Chul;Kim, Young
    • Journal of electromagnetic engineering and science
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    • 제19권1호
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    • pp.42-47
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    • 2019
  • This paper introduces a modified Wilkinson power divider that uses uniform transmission lines for various terminated impedances and an arbitrary power ratio. For the designed power ratio, the proposed divider changes only the electrical lengths of the transmission lines between the input and output ports, and those between the output ports and the isolation resistor. In this case, even when various termination impedances of the ports exist, the divider characteristics are satisfied. To verify the feasibility of the proposed divider, two circuits were designed to operate at a frequency of 2 GHz with 2:1 and 4:1 power splitting ratios and various terminated impedances of 40, 70, and $60{\Omega}$ for one circuit, and 50, 70, and $60{\Omega}$ for the other. The measurement and simulation results were in good agreement.

열화상카메라를 이용한 직물의 물 흡수 및 건조 특성에 대한 실험 연구 (Experimental Study on Water Absorption and Drying Characteristics of Various Fabrics using IR Camera)

  • 김정배
    • 한국분무공학회지
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    • 제28권1호
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    • pp.10-15
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    • 2023
  • Recently, various types of towels and dishcloth dryer products are being widely distributed in Korea. Evaluation methods for water absorption properties of various fabrics have been developed, and there are many studies using them. This study newly intended that whether it is possible to obtain data that can quantitatively analyze the water absorption characteristics of various fabrics, to show the correlation between the water absorption height and the amount of water (water holdup) absorbed, and to experimentally suggest the applicability to evaluate the drying capacity of towel dryer using IR camera. Through these experiments, it was confirmed that quantitative data on the water absorption height of various fabrics can be measured using an IR camera and can be clearly applied to the performance evaluation of actual products.

다양한 디자인 분야에서 건축가의 활동 및 디자인 요소의 적용에 관한 연구 - 알레시사와 협력한 건축가를 중심으로 - (A Study on the Architect's Work Scope and the Application of Design Elements in Various Fields of Design - Focuse on Architects for Alessi -)

  • 서희숙;이상홍
    • 한국실내디자인학회논문집
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    • 제19권2호
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    • pp.24-32
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    • 2010
  • The purpose of this study is to examine the work scope of architects who work for Alessi and their application of design elements in various fields of design. Urban Design, Architectural Design and interior design are interrelated. Thus the designers should have various design experiences for expanding their knowledge of their specialty. These experiences can help not only the university students who will be designers in the future get creative concept, but also architects and interior designers develop their abilities to look at design. As a result, their society competitiveness can be increased. For this reason, this study selects eleven architects who participated in Tea & Coffee set project of Alessi. This study researches how their design elements apply to various design areas and investigates architects's activities not only in their major fields, but also in other design fields. The result of this study is that architects participates in all design fields, except automobile design which is not related to architecture. Especially, among various design areas, architects are likely to participate in architectural design, interior design, and furniture design Contrary to this, they hardly participate in bathroom. Also, one design element applies to various design areas, such as construction, furniture, accessories, and so on.

단체급식소에서 제공되는 소시지-채소 볶음과 마늘종 볶음의 생산단계 및 보관단계에 따른 리보플라빈 함량 변화(1) (Changes in the Riboflavin Content of Stir-Fried Sausage with Vegetable and Stir-Fried Garlic Young Stem at Various Cooking and Holding Processes in Food Service Establishments( I ))

  • 김혜영
    • 한국식품조리과학회지
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    • 제18권4호
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    • pp.461-469
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    • 2002
  • In order to develop a better food preparation method in terms of vitamin retention in food service establishments, the retention rate of riboflavin in two kinds of Korean dish (stir-fried sausage with vegetables, stir-fried garlic young stems) were examined during various cooking stages, holding temperature and duration time. Riboflavin content of the sample was analyzed using by using a HPLC with a fluorescent detector at various holding durations and temperatures. Also the changes in the pH and water contents of the samples were measured during holding at various temperatures to find any relation among the pH, water contents and riboflavin content. In the results, there were significant differences in riboflavin contents at various cooking processes such as washing, slicing, blanching, soaking, etc. Also, the retention rates of riboflavin at various holding methods and temperature were significantly different from one another. Especially 50% reduction of riboflavin content occurred during blanching of young garlic stem and only 38% of riboflavin was left after slicing carrots for stir-frying of sausage.