• Title/Summary/Keyword: New concept

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신개념 로터리 엔진의 개발 (I) - 개념과 이론적 성능 분석 - (Development of A New Concept Rotary Engine (I) - Concept and theoretical performance analysis -)

  • 오문근;이규승;박원엽
    • Journal of Biosystems Engineering
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    • 제28권1호
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    • pp.27-34
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    • 2003
  • Present combustion engines have reached almost at the limit of development due to the fundamental structural problems. This study was carried out to propose a new concept internal combustion engine which has great potential advantages to the conventional engines. Proposed new concept engine is a kind of rotary engine. A rotor is rotating concentrically in a cylinder which is divided into two partitioning valves. and it makes four compartments in the cylinder. The volumes of each of four compartments are changing continuously with the rotor movement, and performs the functions of intake, compression. expansion and exhaust simultaneously. The results of this study can be summarized as follows. 1. Expected theoretical thermal efficiency is 44.9 percent at the condition of 1000rpm and compression ratio of 8.0. which is almost the same as that of the conventional engines. i.e., piston and Wankel rotary engine. 2. The new concept engine has 2. working strokes in every revolution. Therefore. the new concept engine can reduce the specific weight and volume than four-stroke piston engine. 3. The torque variation is very small. therefore minimal noise and vibration are expectable. 4. The new concept engine can reduce mechanical energy loss than piston engine because neither crank mechanism nor eccentrical motion exists.

New product concept evaluation using the AHP

  • Lee, Jae-Hwan;Chang, Suk-Gwon
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회 1989년도 추계학술발표회 발표논문초록집; 이화여자대학교, 서울; 23 Sep. 1989
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    • pp.91-107
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    • 1989
  • New product concept evaluation is one of the most important activities among many possible evaluation activities involved in the whole new product process. This paper aims at exploring the applicability of the Analytic Hierarchy Process(AHP) to this new product concept evaluation. To this aim, an AHP based concept evaluation model was formulated and explained using an illustrative example. A number of issues were also raised and discussed concerning the applicability of AHP to out problem. Finally, some further research areas were identified.

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신개념 스위칭 소자를 위한 모트-절연체 금속 전이 기술 (Mott-Insulator Metal Switching Technology for New Concept Devices)

  • 김현탁;노태문
    • 전자통신동향분석
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    • 제36권3호
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    • pp.34-40
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    • 2021
  • For developing a switching device of a new concept that cannot be implemented with a semiconductor device, we introduce the Mott insulator-metal transition (IMT) phenomenon occurring out of the semiconductor regime, such as the temperature-driven IMT, the electric-field or voltage-driven IMT, the negative differential resistance (NDR)-IMT switching generated at constant current, and the NDR-based IMT-oscillation. Moreover, the possibilities of new concept IMT switching devices are briefly explained.

새로운 개념의 드릴에 의한 구멍가공시 버 형성에 관한 연구 (Analysis on Burr Formation in Drilling with New Concept Drill)

  • 고성림;전근배;이징구
    • 한국정밀공학회지
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    • 제17권3호
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    • pp.114-121
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    • 2000
  • A new concept drill was developed recently (or increasing accuracy and productivity in drilling operation. The burr formation in drilling causes many problems in deburring operation because burrs are formed inside holes and it is difficult to remove them. Burr formations are observed in drilling operation with a new concept drill and are compared with conventional HSS drill. Several workpieces with different materials are drilled with several cutting conditions, velocity and feed rate. The burr in drilling can be classified into three types according to the location of crack. To observe the burr formation mechanism, the cap which is formed with the new concept drill is observed and measured.

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신개념 로터리 엔진의 개발(II) - 실제 사이클의 성능 분석 - (Development of a New Concept Rotary Engine (II) - Performance Analysis of Real Cycle -)

  • 오문근;박원엽;이승규
    • Journal of Biosystems Engineering
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    • 제28권4호
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    • pp.285-294
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    • 2003
  • This study was carried out to propose a new-concept internal combustion engine which has great potential advantages to the conventional engines. Proposed new-concept engine is a kind of rotary engine. A rotor is rotating concentrically in a cylinder which is divided into two partitioning valves, and it makes four compartments in the cylinder. The volumes of each of four compartments are changing continuously with the rotor movement and performs the functions of intake, compression. expansion and exhaust simultaneously. Expected thermal efficiency for the real cycle is 26 percent at conditions of 1,000 rpm and compression ratio of 8.0, which is 3 to 4 percent higher than that of the conventional engines such as the piston engine, gas turbine and Wankel rotary engine. A simulation procedure proved that the new concept engine is functional, and has many potential advantages compared to the existing conventional engines.

A Generalized Model for Homogenized Reflectors

  • Pogosbekyan, Leonid;Kim, Yeong-Il;Kim, Young-Jin;Joo, Hyung-Kook
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1996년도 춘계학술발표회논문집(1)
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    • pp.40-45
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    • 1996
  • A new concept of equivalent homogenization is proposed. The concept employs new set of homogenized parameters: homogenized cross sections (XS) and interface matrix (IM), which relates partial currents at the celt interfaces. The idea of interface matrix generalizes the idea of discontinuity factors (DFs), proposed and developed by K.Koebke and K.Smith. The method of K.Smith can be simulated within framework of new method, while the new method approximates heterogeneous cell better in case of the steep flux gradients at the cell interfaces. The attractive shapes of new concept are: improved accuracy, simplicity of incorporation in the existing codes, equal numerical expenses in comparison to the K.Smith's approach. The new concept is useful for: (a) explicit reflector/baffle simulation; (b) control blades simulation; (c) mixed UO2/MOX core simulation, The offered model has been incorporated in the finite difference code and in the nodal code PANBOX. The numerical results show good accuracy of core calculations and insensitivity of homogenized parameters with respect to in- core conditions.

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신규치과위생사의 조직사회화에 미치는 영향 (Factors influencing organizational socialization in new dental hygienists)

  • 이혜진;민희홍
    • 한국치위생학회지
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    • 제19권5호
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    • pp.803-811
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    • 2019
  • Objectives: This study investigated the factors influencing organizational socialization of new dental hygienists and provides basic data for successful organizational socialization. Methods: Data were collected using self-report questionnaires from 199 new dental hygienists of dental clinic and hospital between June and September 2018. Data analysis using SPSS 22.0 included Independent t-test, one way ANOVA, Scheffe post-hoc test, Pearson correlation coefficients, and multiple regression analysis. Results: The new dental hygienists' professional self-concept, interpersonal ability, and organizational socialization value were $3.27{\pm}0.50$, $3.55{\pm}0.45$, and $3.03{\pm}0.37$, respectively. There were significant positive correlations between professional self-concepts, interpersonal relations, and organizational socialization. A positive correlation was found between professional self-concept and interpersonal relations. Factors affecting organizational socialization of new dental hygienists included the strength of work, interpersonal relations, and professional self-concept. Professional self-concept was the most influential factor leading to 54.7% of the variance in organizational socialization. Conclusions: Therefore, to improve the organizational socialization of new dental hygienists and reduce the turnover rate, it is necessary to develop and implement programs promoting professional self-concept and interpersonal relations.

효율적인 공간도형의 방정식 지도에 관한 연구 (A Study on the Teaching Method of Equation of Figure in Space Effectively)

  • 김일겸
    • 한국학교수학회논문집
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    • 제3권2호
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    • pp.59-67
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    • 2000
  • Two groups of students, who are the students in the natural science course of high school in Korea, learned the equation of figure in space (point, line, plane) to understand more effectively with two different textbooks. One group was taught with the textbook used now in most high schools and the other group was taught with the textbooks systematized by associating old concept with new concept. The results are as follows : 1) We need understand the basic concept of vector plainly and flexibly to apply it to the solution of problems. 2) It helps students understand new concepts how we should establish the concept about point, line and plane in space by applying the concept about those on XY plane, 3) It is very effective in understanding the new knowledge system more easily to analyze the existent concepts and to arrange them systematically for efficient understanding of new concepts. 4) The texts which consist of contents organized by basic concepts improve students' learning ability.

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기존의 적산전력계측 개념의 새로운 평가 (A CRITICAL NOTE ON THE CONCEPT OF THE CONVENTIONAL INTEGRAL ELECTRIC POWER METERING)

  • 오흥국
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.171-173
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    • 2001
  • Conventional potential concept does not allow different currents before and after the electric load. Experimental examples in case of bioloads show a lot of different currents before and after the bioload, which means that the true potential concept is not the conventional concept from Coulomb attraction energy but the new concept from Gibb's free energy. Gibb's free energy is a kind of potential heat energies and also they are rotating electromagnetic waves. We might think that electric current is not a flow of electrons but a flow of rotating electromagnetic waves, which induces electrons' vibrations. A new measuring method for integral electrical power is suggested for the new Gibb's free energy concept.

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