• 제목/요약/키워드: UPS design

검색결과 211건 처리시간 0.029초

Empirical Analysis of Effect of Entrepreneurship on Export Performance: Focusing on the Mediated Effect of Technology Capability and Export Support Policy of Start-Ups

  • Joo, Se-Hwan;Shin, Gun-Hoon
    • Journal of Korea Trade
    • /
    • 제24권6호
    • /
    • pp.173-193
    • /
    • 2020
  • Purpose - This study aims to examine the effect of entrepreneurship of start-ups on export performance when the business closure rate is higher than business start-up rate in Korea. Thus, this study analyzes various factors for start-ups established within the past seven years and uses export performance as an indicator. Prior to analysis of factors, the study defines the concepts of start-up factors based on various studies. Design/methodology - In order to analyze the export performance of startups, this study conducted an empirical analysis using statistical analysis. Theories were established based on previous studies, and hypotheses and research models were designed based on the established theories. Subsequently, in order to verify the research hypothesis and research model, factor analysis such as validity and reliability, and structural equation modeling were analyzed. Findings - As a result of analysis based on previous studies, we found that there is a difference between theoretical and practical aspects. Whereas previous studies showed that market orientation, technology orientation, and social capital have a direct impact on export performance, the present study analyzed that there is no such impact, and that technology capabilities were important as a result of the unique traits of start-ups. Originality/value - Existing studies have limitations in understanding the overall characteristics of a company by using market orientation, technology orientation, and social capital as individual independent variables. In addition, the existing researches have been analyzed in relation to corporate performance, whereas this study has been limited to export performance, so it can be regarded as different from other studies.

BMO모형을 이용한 스타트업 기술사업화 성공요인 연구 (A Success factor for Technology Commercialization for Start-ups by the Weighted-BMO Model)

  • 민광동;허무열;한정희
    • 산경연구논집
    • /
    • 제9권11호
    • /
    • pp.39-54
    • /
    • 2018
  • Purpose - To success, in spite of deficient resources, a start-up company has to check various circumstances. Many researchers proposed different appraisal methods for technology commercialization. But everybody agrees Merrifield is the first one, who is a pioneer of an appraisal model of technology commercialization. After he proposed it, many researchers and field workers developed a more complicated model, which called a BMO model. In this research, considering the circumstances of start-ups that lack available resources, it proposes a new appraisal method for technology commercialization, which is named a weighted-BMO model. Research design, data, and methology - For the new BMO-model, it studied the preceding studies. And it found that the success factors for start-ups were correlated with technology commercialization. After comparing the success factors for technology commercialization of start-ups with BMO appraisal factor, it withdraws the net BMO appraisal model: which we are calling the weighted-BMO model. Results - This study found a few things. First, actually, the BMO appraisal factors related with the success factors of technology commercialization. Second, the weighted-BMO model, which included the entrepreneur ability factor, was more accurately estimated the success of technology-based start-ups than the BMO model. Third, it overcame the weakness of the BMO-model, which did not include quantitative factors. In addition to evaluating the feasibility of the BMO model, we also presented a strategy for the future direction. But, still, it included a few shortcomings, which we are calling the arbitrage of weighted value. Sometimes, the intentional weighted value can deliberate the different valuation. Conclusitons - Due to this study, the weighted-BMO model included appraisal factors related with the success factors of technology commercialization and the entrepreneur ability factor, and quantitative factors. When evaluating the combined score of the existing Merrified BMO components, 35 points of the first pass criterion accounted for 29.17% of the total score, and 80 points of the merit score of the second rank criterion were 66.67% Considering that the weighted sum is taken into account, the baseline score of the weighted summing method for each component of the modified BMO model is 2.92 points, which is 29.17% of the weighted sum total of 10 points. The evaluation score was 6.67 points, 66.67% of the weighted total score of 10 points.

우주급 경통 열-흡습 설계

  • 이덕규
    • 항공우주기술
    • /
    • 제4권1호
    • /
    • pp.108-113
    • /
    • 2005
  • 본 연구 에서는 고해상도 우주용 카메라의 경통부의 복합재 적층설계를 열환경 및 흡습에 의한 영향을 고려하여 수행하고 다층 지그재그이론에 기초하여 개발된 삼각형 유한요소를 이용 열흡 습 해석을 수행하여 융단도표를 통하여 도출된 최적 적층설계가 광학성능 허용범위를 만족하는지 검증 하였다.

  • PDF

광 픽업 장치의 $H_{\infty}$ 위치 서보제어 ($H_{\infty}$ Position Servo Control of Optical Pick-Ups)

  • 임승철;김윤영
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 1996년도 춘계학술대회논문집; 부산수산대학교, 10 May 1996
    • /
    • pp.119-124
    • /
    • 1996
  • Recently, high speed optical disk drives are increasingly demanded to read or write data fastly enough. To this end, both structure and controller designs of their optical pick-ups should be improved concurrently. In this paper, the pick-up during auto-focusing motion is mathematically modelled retaining all its peculiar features. The model turns out a linear time invariant system suitable for a control design method named H$_{\infty}$ which ensures robust stability in the presence of system uncertainties. Numerical simulation are performed to demonstrate the controller robustness with appropriate performance specifications being satisfied..

  • PDF

3상 UPS의 정전압 출력특성 향상을 위한 개선된 데드비트 디지털 제어기의 설계 (Design of Modified Deadbeat Digital Controller for Output Voltage Improvement of 3-Phase UPS)

  • 조준석;이승요;김홍성;최규하
    • 전력전자학회논문지
    • /
    • 제5권1호
    • /
    • pp.1-10
    • /
    • 2000
  • 본 논문에서는 무정전전원장치(UPS)에 사용되는 3상 PWM 인버터의 정전압 제어특성 향상을 위해 개선된 형태의 데드비트 제어방식을 제안하고 이의 설계를 수행한다. 일반적으로 UPS는 전압제어 루프 안에 전류제어기를 두는 형태의 이중 제어 루프 구조를 가지며, 빠른 과도응답 제어 특성을 얻기 위해 데드비트 제어기가 많이 적용되어 왔다. 그러나 전압, 전류의 이중 제어구조를 갖는 데드비트 제어기의 경우 동일한 극배치 특성으로 인해 기존의 제어 시스템은 불안정한 측면을 갖게된다. 이러한 제어특성의 개선을 위하여 분리된 극배치를 가지는 제어기구조를 제안하며, 이는 전압제어기 출력으로 1차 지수함수 응답을 사용하는 변형된 형태의 데드비트 제어기로 구성된다. 아울러 부하 변동에 따른 부하전류의 외란성분을 전향보상하기 위하여 전차원 외란 관측기를 설계하고 시뮬레이션 및 실험을 통하여 제안된 시스템의 우수성을 확인한다.

광 픽업 장치의 H${\infty}$이산시간 서보제어 (H${\infty}$discrete-time servo control of optical pick-ups)

  • 임승철;김윤영
    • 소음진동
    • /
    • 제6권4호
    • /
    • pp.521-528
    • /
    • 1996
  • Recently, higher speed optical disk drives including computer CD-ROM drives tend to be increasingly demanded to read or write the enormous volume of digital data. To this end, both structure and controller designs of the optical pick-ups should be improved concurrently. In this paper, the pick-up during auto-focusing motion is mathematically modelled retaining all its peculiar features. The model turns out a linear time invariant system suitable for a control design namedH${\infty}$ which ensures robust stability in the presence of system uncertainties. Numerical simulations are performed to demonstrate the robustness with appropriate performance specifications being satisfied. In addition, as the implementation issue of it, procedures of temporal discretization as well as model reduction of the controller are also addressed.

  • PDF

인버터 출력전력 순환기능을 갖는 무정전 전원공급 시스템의 설계 및 성능평가 (Design and Performance Evaluation of UPS System with the Circulating Function of Inverter Output Power)

  • 이동주;백석민
    • 전력전자학회:학술대회논문집
    • /
    • 전력전자학회 2013년도 전력전자학술대회 논문집
    • /
    • pp.143-144
    • /
    • 2013
  • 당사가 개발한 무변압기형 UPS는 정상 운전동작시에는 인버터 출력전압 고조파 함유율을 최소화하고 순환부하시험 동작시에는 인버터 출력전류 고조파 함유율을 최소화시킬 수 있는 출력필터가 필요하다. 그래서 본 연구에서는 이러한 두 설계조건을 만족하도록 하는 출력필터 설계절차를 설명하였고 그 설계절차의 타당성을 확인하기 위해서 설계된 인버터 출력필터를 적용한 3상 10kVA UPS 시제품을 제작하여 순환부하시험을 통하여 그 성능을 확인하였다.

  • PDF

0.7 MJ UPS용 초전도 케이블의 ?치 특성 (Quench Characteristics of the Superconduction Cable for a 0.7 MJ UPS)

  • 류경우;김해종
    • 한국전기전자재료학회논문지
    • /
    • 제11권7호
    • /
    • pp.565-570
    • /
    • 1998
  • Recently a few MJ superconducting magnetic energy storage ($\mu$ SMES) devices become commerci-ally available as one of the energy storage devices for uniterruptible power supply (UPS) systems. For such a ($\mu$ SMES) devics, a few kA class superconducting cables with high current density, high stability and excellent pulse characteristics are required. To acquire data for the superconduction cables related to design and fabrication of a 0.7 MJ $\mu$ SMES device, we tested critical currents and quench characteristics for several winding tensions and various remping rates especially. It is shown from the results that winding tensions have much influence on quench currents of the $\mu$ SMES devices.

  • PDF

공동주택 화장실의 급기구 및 배기팬 설치 위치에 따른 환기효과에 관한 연구 (A Study on the Ventilation Effect by Establishment Location of Supply Opening and Exhaust Fan of Bathroom in Apartment House)

  • 함진식
    • 한국주거학회:학술대회논문집
    • /
    • 한국주거학회 2002년도 추계학술발표대회
    • /
    • pp.321-326
    • /
    • 2002
  • To design mechanical ventilation for bathroom of apartment houses where air supply and exhaust are taken Into consideration, mock-ups of ventilation systems, widely used in bathroom of apartment houses with an area of 100$m^2$, were made and installed in a laboratory, These ventilation mock-ups were available for control of air supply and exhaust, and the size of supply openings were 40cm$\times$1cm, 40cm$\times$3cm, 40cm$\times$5cm. They were installed at five positions, spaced 40cm at a height of 25cm from the floor. and the position of exhaust fans were four corners and center Exhaust fan established each one on corner of the ceiling and one in center. As result that measure ventilation effect by each condition, size of hole that supply air is big, and ventilation effect took effect to be good establishment location is low, Also, distance of exhaust fan is far with hole that supply air, ventilation effect took effect by superior thing.

  • PDF

6자유도 병렬형 모션 시뮬레이터 개발 (Development of a New 6-DOF Parallel-type Motion Simulator)

  • 김한성
    • 한국생산제조학회지
    • /
    • 제19권2호
    • /
    • pp.171-177
    • /
    • 2010
  • This paper presents the development of a new 6-DOF parallel-kinematic motion simulator. The moving platform is connected to the fixed base by six P-S-U (Prismatic-Spherical-Universal) serial chains. Comparing with the well-known Gough-Stewart platform-type motion simulator, it uses commercialized linear actuators mounted at the fixed base whereas a 6-UPS manipulator uses telescopic linear ones. Therefore, the proposed motion simulator has the advantages of easier fabrication and lower inertia over a 6-UPS counterpart. Furthermore, since most forces acting along the legs are transmitted to the structure of linear actuators, smaller actuation forces are required. The inverse position and Jacobian matrix are analyzed. In order to further increase workspace, inclined arrangement of universal joints is introduced. The optimal design considering workspace and force transmission capability has been performed. The prototype motion simulator and PC-based real-time controller have been developed. Finally, position control experiment on the prototype has been performed.