• 제목/요약/키워드: Preliminary study

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달착륙선 추진시스템 기본 설계 및 지상 모델 설계 (Preliminary design of lunar lander propulsion system and ground test model)

  • 김수겸;유명종
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2010년도 제35회 추계학술대회논문집
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    • pp.581-584
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    • 2010
  • 한국항공우주연구원에서는 2020년대에 수행하기로 계획되어 있는 달탐사를 준비하기 위해 달 탐사선 및 착륙선 추진시스템의 기본 설계를 진행하고 있으며 추진시스템의 설계 검증 및 추력기의 성능 검증을 위한 착륙 시험 계획을 진행하고 있다. 올해는 그 첫 단계로 추진시스템의 개념 설계가 이루어졌으며 지상 시험을 수행하기 위한 200N급 단일추진제 추력기의 설계가 이루어졌다. 본 논문에서는 추진계 설계를 위한 trade-off 연구 결과와 추진계 및 추력기의 기본 설계에 대해 소개할 예정이다.

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공정이행관리를 위한 선행작업관리 시안 (A Study on the Method of Preliminary Works Management for a Schedule Performance Management)

  • 박홍태;송용선
    • 한국산학기술학회논문지
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    • 제9권3호
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    • pp.757-764
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    • 2008
  • 효율적인 공정이행관리를 통해서 건설공사 일정의 불필요한 공기지연을 사전에 예방하고, 나아가 품질확보를 위하여 각 공정의 내용을 정확하게 숙지하고 관리하는 일이 중요하다. 더욱 중요한 것은 공사계획에 따른 공정이 원활하게 진행될 수 있도록 각각의 공정에 필요한 선행작업들을 체계화하여 관리하는 것이다. 이를 위하여 본 연구에서는 아파트공사를 대상으로 이정표 중심, 작업공종 중심, 활동 중심, 작업 담당자 중심으로 구분하여 선행작업관리 시안을 제시하였다.

디지털 드로잉 기법과 특수 분장을 활용한 3D 아트메이크업 디자인 프로세스 (3D Art Make Up Design Process utilizing Digital Drawing Technique and Special Make Up)

  • 신원선;신세영
    • 패션비즈니스
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    • 제15권2호
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    • pp.131-144
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    • 2011
  • The purpose of this study is to propose 3D art make-up design process by reproducing real objects through preliminary digital drawing with Photoshop (Photo Shop CS4.0, Adobe, USA) and using special make-up that has never been done previously, and produce creative problem solving plan to make concrete expanding thoughts and ideas. As for this study method, this study was composed of preliminary study, literature study by book examination and positive study on design process that performed preparatory work and reproduced real objects. Real case study by art make-up design process can improve effective design expressing ability by utilizing special make-up, diversify techniques, extend expression areas by materials, and create unique design. In addition, preliminary work by digital drawing, a process to predict real object work in advance, could reduce time and cost while improving work skill for work production, raise design accuracy and make easy the modification of idea. This study is anticipated to activate digital make-up by various digital techniques including Photoshop.

진술선호방법을 이용한 공공 데이터의 가치 평가: 농업토양정보 데이터베이스 사례 (Valuation of Public Data Using Stated Preference Method: The Case of Agriculture Soil Database)

  • 이상호;하성호;정기호
    • 한국정보시스템학회지:정보시스템연구
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    • 제27권4호
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    • pp.149-165
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    • 2018
  • Purpose As Korean economy has been sluggish in recent years, firms' interest in publicly financed projects has increased due to the relatively increasing proportion in the economy. Since 1999, publicly financed projects in Korea need to undergo preliminary feasibility study to evaluate economic efficiency and policy quality if they are larger than a certain scale. The benefits of public projects are one of the most important factors in the preliminary feasibility study but are difficult to estimate due to their nature. Design/methodology/approach This study estimates the benefits of the agricultural soil information database, a public database in Korea. The method used in the study is the stated preference method which is formally used in Korea's preliminary feasibility study. Data are collected through surveys and a logit model is constructed to be estimated by the maximum likelihood estimation method. Findings As the first study evaluating a public database, this study can be used as a baseline in all public database projects developed in the future. In addition, this study can contribute to improving the understanding of both private companies and public organizations who are interested in the cost-benefit analysis and estimation procedure for the publicly financed projects.

Language Attitude Among the Border Community at Telok Melano, Malaysia and Temajuk, Indonesia: A Preliminary Study

  • Dilah Tuah;Chong Shin;Muhammad Jazlan Ahmad Khiri
    • 수완나부미
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    • 제15권1호
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    • pp.229-254
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    • 2023
  • This study observes the language attitude and maintenance of the border community in Telok Melano, Lundu (Sarawak, Malaysia) and Desa Temajuk, Sambas (West Kalimantan, Indonesia). The main objective of this study is to study the language attitudes of two cross-border community who shares the socio-cultural, language, and economic realms. The research data is collected qualitatively through conversation recordings, face-to-face interviews, and participant observations. In this preliminary study, twelve informants (six from Telok Melano and six from Desa Temajuk) were chosen based on the quota sampling method. The questions for the interview were set according to three characteristics of language choice proposed by Garvin and Mathiot (1968), namely language loyalty, language pride, and the awareness of norms. The result of this study indicates that language loyalty, language pride, and awareness of the norms towards the speakers' mother tongue and national language are relatively high. In terms of identity maintenance issues, this study found that the community in Telok Melano (Sarawak), originally identify themselves as "Sambas Malays," shifted to "Sarawak Malays" after the formation of Malaysia in 1963. This preliminary study serves as a basis for further research particularly on the complexity of issues concerned with the border communities in the Southwest of Sarawak.

사회적기업 및 일반기업 예비 창업가의 창업효능감이 창업의도에 미치는 영향: 사회적 지지의 조절효과 (The Impact of Entrepreneurial Self-Efficacy on the Entrepreneurial Intention of Preliminary Social Entrepreneurs and General Entrepreneurs: The Moderating Effect of Social Support)

  • 조영복;손진현;정기범;이나영
    • 벤처창업연구
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    • 제13권1호
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    • pp.89-104
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    • 2018
  • 본 연구의 목적은 사회적기업 및 일반기업 예비 창업가의 창업효능감과 창업의도의 관계를 규명하고, 사회적 관계를 통해 얻을 수 있는 사회적 지지가 창업효능감과 창업의도간의 관계에서 어떠한 영향이 있는지 분석하는데 있다. 또한 사회적기업과 일반기업을 비교분석하여 조직 특성에 따른 창업의도에 미치는 영향을 비교해보고자 하였다. 일반 예비 창업가 102명, 사회적기업 예비 창업가 126명을 대상으로 자료를 수집하였으며, 실증 분석 결과 일반기업과 사회적기업 예비 창업가 모두 창업효능감이 창업의도에 정(+)의 영향을 미침을 확인하였다. 한편 사회적 지지의 경우 일반기업 예비 창업가에게는 조절효과를 보이지 않았으나, 사회적기업 예비 창업가에 대하여 평가적 지지와 물질적 지지가 조절효과를 보였다. 본 연구는 창업효능감이 창업의도에 영향을 살펴봄으로써 창업과정이 실제로 구체화되기 위해서는 예비창업가의 성공에 대한 확신적 의지와 자신감 즉, 창업효능감의 중요성을 확인하였다. 또한 사회적 가치 창출과 사회적 성과를 우선시 하는 사회적기업의 경우, 일반 기업의 창업과정과 차이가 있을 것으로 예상하여, 조절변수로서 사회적 지지를 투입한 결과, 소속집단이나 사회로부터의 지지를 통해 축적된 사회적 자본이 사회적기업 창업에 완충작용을 하고 있음을 검증하였다. 본 연구의 결과를 바탕으로 창업지원 및 교육 현장에서 예비 창업가들의 창업효능감을 발현시키고, 향상시킬 수 있는 교육프로그램이나 지원제도, 활용 방안의 필요성이 제기되며, 특히 사회적기업 예비 창업가들은 사회적인 공감과 지지가 필요함을 강조할 수 있다. 끝으로 본 연구의 한계와 향후 연구방안을 제언하였다.

복합용도 개발 도시재생 사업에서의 단위 공간 기반 개산견적 모델링 가이드 제안 - ○○시 ○○역 복합환승센터 사례를 중심으로 - (A Proposal of Modeling Guide of the Unit Space-based Preliminary Cost Estimation in Urban Renewal Mix-Used Development - Case Study on ○○ Transfer Station Complex -)

  • 강신엽;안재홍;김주형
    • 한국BIM학회 논문집
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    • 제3권1호
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    • pp.11-20
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    • 2013
  • Mix-used development in urban renewal project is done to effectively utilize the limited downtown. Generally unlike a single project, It features placing a large number of different facilities(residential, commercial, business, cultural, etc.) which is each other organically linked. The purpose of this study is to suggest the method of modeling guide for 3D preliminary cost estimation considering visual and intuitive judgement of space in mix-used development Urban Renewal project. In this research, introducing SME(Standard Module and Element) breakdown structure, FID(Finish Identity) for estimating building space unit-based quantity take off was implemented. It could narrow the discrepancy of opinion between the stakeholders with more accurate cost-estimates, comparing to the traditional methods.

양정곡선 기울기를 고려한 원자로 냉각재 펌프의 수력설계 (Hydraulic Design of Reactor Coolant Pump Considering Head Curve Slope at Design Point)

  • 유일수;박무룡;윤의수
    • 한국유체기계학회 논문집
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    • 제14권1호
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    • pp.18-23
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    • 2011
  • The hydraulic part in reactor coolant pump consists of suction nozzle, impeller, diffuser, and discharge nozzle. Among them, impeller is required to be designed to satisfy performance requirements such as head, NPSHR, and head curve slope at design point. Present study is intended to suggest the preliminary design method sizing the impeller size to satisfy the design requirement particularly including head curve slope at design point. On a basis of preliminary design result, hydraulic components have been designed in detail by CFD and then manufactured in a reduced scale. Experiment in parallel with computational analysis has been executed in order to confirm the hydraulic performance. Comparison results show good agreement with design result, confirming the validity of design method suggested in this study.

동기관음의 스펙트럼 차이를 이용한 비강 특성 산출: 예비 연구 (A new method of Extracting the Filter Characteristics of the Nasal Cavity Using Homorganic Nasal-Stop Sequences: A Preliminary Report)

  • 박한상
    • 대한음성학회지:말소리
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    • 제53호
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    • pp.17-35
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    • 2005
  • A New Method of Extracting the Filter Characteristics of the Nasal Cavity Using Homorganic Nasal-Stop Sequences: A Preliminary R eportHansang ParkThis study provides a new method of extracting the filter characteristics of the nasal cavity. Korean lenis stops are realized as voiced in the homorganic nasal-lenis stop sequences between vowels. Since the only difference between the two members of the homorganic nasal- lenis stop sequences, such as [mb], [nd], and [ g], is whether the passage to the nasal cavity is open or not, the subtraction of the LPC spectrum of the voiced stop from that of the preceding nasal leads to the filter characteristics of the nasal cavity of an individual speaker regardless of place of articulation. The results suggest that various attempts should be made to extract a robust filter characteristics of the nasal cavity by giving variation to LPC coefficients and by paying particular attention to speech samples. This study is significant in that it provides a preliminary report about a new method of extracting the filter characteristics of the nasal cavity.

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경량화 소형 위그선 구조 예비 설계에 관한 연구 (Study on Preliminary Structural Design of Light Weight Small Scale WIG Craft)

  • 공창덕;박현범;김주일;이승현;윤재휘
    • 항공우주시스템공학회지
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    • 제1권1호
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    • pp.36-44
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    • 2007
  • This study was performed on preliminary structural design of a small scale WIG craft which has been developed as a next generation high speed maritime transportation system in Korea. A composite structure design using the foam-sandwich for main wing and tail fins and the honeycomb sandwich and skin-stringer-ring frame for fuselage was applied for weight reduction as well as structural stability. A commercial FEM code, NASTRAN for was utilized to confirm the structural safety for the reiterate design modifications to meet design requirements including the target weight. Each main wing was jointed with the fuselage by eight high strength insert bolts for easy assembling and disassembling as well as for assuring the required 20 years service life. For control surface structural design, the channel type spar, the foam sandwich skin and the lug joint were adopted.

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