• 제목/요약/키워드: self-starting

검색결과 297건 처리시간 0.026초

북한이탈주민의 창업 개인특성과 창업동기가 창업의지에 미치는 영향 (The Influence of North Korean Refugees' Individual Characteristics and Entrepreneurial Motives on Entrepreneurial Intention)

  • 박남태;이보영
    • 벤처창업연구
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    • 제11권5호
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    • pp.67-75
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    • 2016
  • 북한이탈주민은 남한사회에서 적응하는 과정에서 경험하는 경제적인 어려움은 낮은 소득수준과 전문성 부족에서 찾아볼 수 있다. 따라서 본 연구는 북한이탈주민을 대상으로 하는 창업지원을 위해서 정책과 제도개선 방안을 목적으로 수행되었다. 본 연구결과 창업자의 개인적 특성인 자기효능감이 창업의지에 영향을 미치는 것으로 나타났다. 또한 창업동기와 창업교육도 창업의지에 영향을 미치는 것으로 나타났다. 사회적 적응의 조절효과를 살펴본 결과 창업자의 개인적 특성 중 위험감수성향과 창업경험이 사회적응과의 상호작용과 창업동기와 사회적응의 상호작용을 통해서 정의 영향을 미치는 것으로 나타났다. 본 연구결과를 바탕으로 북한이탈주민의 효율적인 창업지원 정착을 위해서는 창업자의 자기효능감을 높일 수 있는 창업교육이 필요하며, 창업동기와 위험감수성향과 사회적응 정도에 따라 창업지원이 이루어져야 할 것이다.

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Flow-driven rotor simulation of vertical axis tidal turbines: A comparison of helical and straight blades

  • Le, Tuyen Quang;Lee, Kwang-Soo;Park, Jin-Soon;Ko, Jin Hwan
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제6권2호
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    • pp.257-268
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    • 2014
  • In this study, flow-driven rotor simulations with a given load are conducted to analyze the operational characteristics of a vertical-axis Darrieus turbine, specifically its self-starting capability and fluctuations in its torque as well as the RPM. These characteristics are typically observed in experiments, though they cannot be acquired in simulations with a given tip speed ratio (TSR). First, it is shown that a flow-driven rotor simulation with a two-dimensional (2D) turbine model obtains power coefficients with curves similar to those obtained in a simulation with a given TSR. 3D flow-driven rotor simulations with an optimal geometry then show that a helical-bladed turbine has the following prominent advantages over a straight-bladed turbine of the same size: an improvement of its self-starting capabilities and reduced fluctuations in its torque and RPM curves as well as an increase in its power coefficient from 33% to 42%. Therefore, it is clear that a flow-driven rotor simulation provides more information for the design of a Darrieus turbine than a simulation with a given TSR before experiments.

자기 포화 영역을 갖는 단상 6/6 SRM의 자기 구조 해석 및 개선 (Analysis and Improvement for Single 6/6 SRM with a Saturable Area)

  • 오석규
    • 한국자기학회지
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    • 제27권2호
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    • pp.70-75
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    • 2017
  • 단상 SRM은 자기동이 어려운 관계로 다양한 방법으로 자기동을 실현시키려는 연구가 진행되고 있다. 보조자석을 사용하거나 보조극 등을 만들어 자기동을 실현시키는 방법들이 연구되고 있다. 최근에 회전자 형상에 변화를 주어 기동할 수 있는 방법이 제시되었다. 이는 회전자 형상에 변화를 주어 부분적으로 자기포화 정도를 다르게 하여 자기동을 실현하는 방식이다. 본 논문에서는 자기 포화 영역을 갖는 단상 6/6 SRM의 자기구조를 해석하고 기존의 자기구조를 개선하는 것을 목적으로 한다. 이 자기 해석을 위해 유한요소법 해석 프로그램인 FLUX2D를 사용하였다.

단상 스위치드 릴럭턴스 모터에 설치된 영구자석 기동장치의 디텐트 토크 (Detent Torque of Parking Magnet Starting Device Installed in the Single-Phase Switched Reluctance Motor)

  • 김준호;이승민
    • 한국전기전자재료학회논문지
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    • 제23권5호
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    • pp.408-412
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    • 2010
  • The single-phase switched reluctance motor(SRM) generates the positive torque in the restricted section. So, it can not started by itself and the torque ripple is heavier than poly-phase. For self-starting and fixing rotating direction, the rotor should be placed at the rising inductance slope when stationary. The parking permanent magnet locates the rotor in the fixed position, which can be started by it-self. It is very simple and cost effective but has some drawbacks. It affects the rotor during the operation, so the characteristics of motor, such as a torque, speed, and ripple are changed to go bad. This paper presents the detent torque of parking magnet starting device through the finite element analysis and experiments. The finite element analysis is performed at incremental rotor positions over one detent torque cycle for any one pole. The prototype, fabricated in the previous research, is used for the experiments. The inductance, instant torque, and detent torque are calculated using the terminal voltage and phase current. Finally, the finite element analysis result and the experiment result are compared for analysis and validity.

대형 동기 전동기 기동실패방지를 위한 여자기회로 과도현상 해석 (Excessive Condition Interpretation of a Exciter Circuit to Prevent Starting Failure of Large Synchronous Motor)

  • 박진훈;조내수;권우현;임성훈;윤경섭;김우현
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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    • pp.739-740
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    • 2006
  • According to the rapid growth of high speed and precise industry, the application of synchronous motor has been increased. In the application fields, the large synchronous motor is not a self-starting motor. The rotor is heavy and, from a dead stop, it is impossible to bring the rotor into magnetic lock with the rotating magnetic field for this reason, all synchronous motor have some kinds of starting device. A simple starter is another motor which brings the rotor up to approximately 96 percent of it synchronous speed. The starting motor is disconnected and the rotor locks in step with the rotating field. The more commony used starting method is to have the rotor to include a squirrel cage indution winding. This indution winding brings the rotor almost to synchronous speed as an induction motor. So, this paper describes excessive condition interpretation of a exciter circuit to prevent starting failure of large synchronous motor. the large synchronous motor needs safety of it in accordance with operating frequent start and stop. the operating Problem point of synchronous motor appears potential element damage of Exciter circuit because synchronous motor is caused synchronous separation. hence we eliminate it and improve starting toque.

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출발상 제어에 의한 자기복합화 미세구조의 탄화규소 세라믹스 제조 (Preparation of Silicon Carbide Ceramics with Self-reinforced Microstructure by the Control of Starting Phases)

  • 이종국;강현희;이은구;김환
    • 한국세라믹학회지
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    • 제34권12호
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    • pp.1240-1246
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    • 1997
  • Silicon carbides with self-reinforced microstructure which hore a small grain matrix and dispersed large grains with rod-like type were prepared by the liquid-phase sintering and the control of starting phases of raw materials. The specimens with self-reinforced microstructure could be obtained from the compacts with mixed compositions of $\alpha$-SiC and 10-50 % $\beta$-SiC powders and by the pressureless sintering at 185$0^{\circ}C$ for 5h. Large grains with rod or plate-like types were 4H-SiC and small grains with equi-axed type were 6H-SiC. Fracture grains with rod or plate-like types were 4h-SiC and small grains with equi-axed type were 6H-SiC. Fracture toughness of specimens with self-reinforced microstructure was increased by the crack deflection and formation of microcracking due to the existence of rod-like large grains during crack propagation.

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원칩 마이컴을 이용한 단상유도전동기의 주권선 제어에 관한 연구 (A Study on the Main Winding Control of Single Phase Induction Motor using One-Chip Micom)

  • 박수강;백형래
    • 대한전기학회논문지:전기기기및에너지변환시스템부문B
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    • 제49권1호
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    • pp.70-76
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    • 2000
  • This paper describes a one-chip micom controller and phase angle control method for self-starting and energy saving of single-phase induction motor. The proposed method is based on the optimal efficiency control which is running by variable phase angle of main winding current such as to maintain the maximum efficiency characteristics of the motor, in voltage control with TRIAC. Experiments are focused on a capacitor starting single-phase induction motor. The optimal energy saving by variable phase angle control are verified by experimental results. Also, auxiliary winding was controlled by electronic starting switch.

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영구자석 기동장치의 유무에 따른 회전자 돌극형 단상 SRM의 순간 토오크 (Instant Torque of Salient Pole Rotor Type Single-Phase SRM According to Installed Permanent Magnet Starting Device or Not)

  • 김준호;이은웅;이종한;김용헌;이현우;이민명
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 하계학술대회 논문집 B
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    • pp.959-961
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    • 2004
  • A multi pole SRM(switched reluctance motor) is applied by the regulated current in regular sequence. So, it can be started by itself. But a single phase SRM can not be started by itself because the positive torque is only generated in the limited zone which the inductance is increased. Therefore, it is required auxiliary device for self starting which place the rotor in start position. The prototype was designed and fabricated in the previous research. It has the permanent magnet, which is installed in the bottom of the rotor, for self starting. But the permanent magnet affect the prototype during operation and cause the decrease of the torque and speed. The influence of the permanent magnet on the average torque and speed was already confirmed. On this paper, the instant torque of the prototype was calculated from the experiment results which is the inductance and current according to installed permanent magnet or not.

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소규모자영업의 경제적$\cdot$교육적 지원 선택의 영향요인 (The Determinants of Economic and Educational Supports Selection of Small Self-employed Business)

  • 홍성희
    • 가족자원경영과 정책
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    • 제9권2호
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    • pp.1-21
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    • 2005
  • The purpose of this study was to analyze the effect of the influencing factors on the economic and educational supports selection of small self-employed business. A sample of 321 was selected from self-employed workers living in Daegu. For data analysis, logistic regression was used. The major findings were as follows: 1 The determinants of the economic supports selection in self-employed business were father's working experiences in self-employed business, taking employees or not in business, having housing ownership or not, and as well as the amount of starting capital. 2. The determinants of the educational supports selection in self-employed business were self-employer's working experience as self-employed before or not, and empowerment with self-employed work.

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공연 시 배우의 각성변화와 심리적 자기조절 분석 (Analysis on Psychological Self-regulation and Arousal Variation of Actors on Performance)

  • 홍길동;이홍식;이형국;오진호;이기호
    • 한국콘텐츠학회논문지
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    • 제8권12호
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    • pp.176-189
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    • 2008
  • 본 연구는 공연 시 배우의 심박수의 각성변화와 유발된 각성상태에 대한 심리적 자기조절을 분석하는데 그 목적이 있다. 연구대상자는 연극 전문극단에 소속되어 있는 배우 5명을 목적적 표본추출하였다. 각성변화를 측정하기 위해서 심박수 측정기를 활용하였고, 자기조절 행동을 관찰 및 기록할 수 있는 행동 관찰지를 사용하였으며, 공연종료 후 개인별 심층상담을 실시하였다. 심박수 변화에 대한 평균과 표준편차를 산출하여, 공연 시간대별 변화 추이를 그래프화 하였으며, 자기조절 행동을 분석하기 위해 질적 연구방법을 실시하였다. 도출된 연구결과는 다음과 같다. 첫째, 배우들은 공연이 시작되기 전부터 심박수의 각성수준이 높아지는 변화를 나타냈으며, 공연 시작 20분 전부터 5분 전까지 가장 높은 각성상태를 보였다. 둘째, 공연 시작 전 심호흡, 호흡 가다듬기, 자기대화, 배우들과의 대화, 대본연습에 집중, 화장실 가기, 흡연, 복장점검 등의 자기조절적 행동을 나타냈다. 셋째, 공연 시 높아진 각성상태를 조절하기 위해서 이완기법, 자기집중화, 자신감강화, 상황대처 및 적응 등과 같은 심리적 자기조절 방법을 사용하는 것으로 나타났다.