• 제목/요약/키워드: Small park

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열안정성을 고려한 초소형 정보저장기기용 액추에이터 구조설계 (Structural design of small form factor swing arm type actuators with thermal stability)

  • 박철;유정훈;박노철;박영필;도야건;중촌자남
    • 정보저장시스템학회논문집
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    • 제2권3호
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    • pp.208-213
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    • 2006
  • The present state of the design of swing arm actuators for optical disc drives is to obtain the high efficient dynamic characteristics within a very compact volume. As a necessary consequence, the need of the small form factor (SFF) storage device has been arisen as major interests in the information storage technology. In this paper, we suggest the miniaturized swing arm type actuator that has high efficient dynamic characteristics for SFF optical disk drive (ODD). For the operating mechanism, it uses a tracking electromagnetic (EM) circuit for a focusing motion together. Moreover, due to the size constraint, the thermal stability of optical head is important. Therefore, the actuator is designed to emit the heat, which is generated by optical pick-up, along the actuator body easily. Initial model is designed based on the topology optimization method considering the thermal conductivity. Then, the structural parts of the actuator are modified to maintain the high sensitivity and to have wide control bandwidth by the design of experiments method (DOE) and new concept of decreasing mass and inertia. Finally, a swing arm type actuator for SFF ODD is suggested and its dynamic characteristics are verified.

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Reduction of TNE ${\alpha}-induced$ Oxidative DNA Damage Product, 8-Hydroxy-2'-Deoxyguanosine, in L929 Cells Stably Transfected with Small Heat Shock Protein

  • Park, Young-Mee;Choi, Eun-Mi
    • The Korean Journal of Physiology and Pharmacology
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    • 제1권2호
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    • pp.209-219
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    • 1997
  • Previous studies have demonstrated that oxidative stress involving generation of reactive oxygen species (ROS) is responsible for the cytotoxic action of $TNF{\alpha}$. Protective effect of small heat shock proteins (small HSP) against diverse oxidative stress conditions has been suggeted. Although overexpression of small hsp was shown to provide an enhanced survival of $TNF{\alpha}$-sensitive cells when challenged with $TNF{\alpha}$, neither the nature of $TNF{\alpha}$-induced cytotoxicity nor the protective mechanism of small HSP has not been completely understood. In this study, we have attempted to determine whether $TNF{\alpha}$ induces oxidative DNA damage in $TNF{\alpha}$-sensitive L929 cells. We chose to measure the level of 8-hydroxy-2'-deoxyguanosine (8 ohdG), which has been increasingly recognized as one of the most sensitive markers of oxidative DNA damage. Our results clearly demonstrated that the level of 8 ohdG increased in L929 cells in a $TNF{\alpha}$ dose-dependent manner. Subsequently, we asked whether small HSP has a protective effect on $TNF{\alpha}$-induced oxidative DNA damage. To accomplish this goal, we have stably transfected L929 cells with mouse small hsp cDNA (hsp25) since these cells are devoid of endogenous small hsps. We found that $TNF{\alpha}$-induced 8 ohdG was decreased in cells overexpressing exogenous small hsp. We also found that the cell killing activity of $TNF{\alpha}$ was decreased in these cells as measured by clonogenic survival. Taken together, results from the current study show that cytotoxic mechanism of $TNF{\alpha}$ involves oxidative damage of DNA and that overexpression of the small hsp reduces this oxidative damage. We suggest that the reduction of oxidative DNA damage is one of the most important protective mechanisms of small HSP against $TNF{\alpha}$.

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땅콩의 초형별 생태적 특성에 관한 연구 III. 초형별 건물생산능력과건물 분배율 (Studies on the Ecological Characteristics for the Plant Types in the Peanut(Arachis hypogaea L.) III. The Differences in Dry Matter Production and Distribution Ratio of Dry Matter Produced among Plant Types)

  • 이정일;박용환;박연규
    • 한국작물학회지
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    • 제30권1호
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    • pp.63-68
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    • 1985
  • 땅콩의 초형, 재배양식에 따른 건물생산능력 및 건물분배율을 구명하고저 virginia소립종, virginia대립종, spanish, valencia, shinpung의 5초형에 속하는 10품종을 공시, 재배양식 2수준(피복, 무피복)으로 하여 시험을 실시하였던 바 그 결과를 요약하면다음과 같다. 1. 건물생산량은 피복재배의 경우 virginia-large seed 1,556g/$m^2$, virginia-small seed 1,347g/$m^2$, shinpung 1,307g/$m^2$, spanish 1,170g/$m^2$, valencia 1,120g/$m^2$이었으며 무피복재배에서는 virginia-large seed 1,389g/$m^2$, virginia-small seed 1,267 g/$m^2$, shinpung 1,192g/$m^2$, spanish 1,066g/$m^2$, valencia 1,035g/$m^2$였다. 2. 최대건물생장속도(CGR)는 virginia-large seed 19.61~20.03g/$m^2$/day, virginia-small seed 18.22~23.4lg/$m^2$/day, shinpung 16.33~19.77g/$m^2$/day, spanish 13.86~16.28g/$m^2$/day, valencia 14.97~16.25g/$m^2$/day였다. 3. 엽면적지수(LAI)는 무피복재배보다 피복재배에서 높았는데, 피복재배의 경우 virginia-large seed 17.2 >virginia-small seed 7.0 > spanish 5.5 > valencia=shinpung 5.4순이었고, 무피복재배에서는 virginia-large seed 6.1 > virginia - small seed 5.8 > spanish 5.0 > valencia 4.9 > shinpung 4.4 순으로 virginia-large seed가 피복, 무피복재배에서 모두 높았다. 4. 경, 엽, 근의 건물분배율은 생육이 진전됨에 따라 감소하였고 협실의 건물분배율은 증가하는 경향으로등숙초기(7월말)에 있어서 피복재배의 경우 shinpung 86%> virginia-small seed 64%>virginia-large seed 63%>spanish 45%>valencia 44%순이었으며 무피복재배에서는 shinpung=spanish=valencia 60%> virginia - large seed 45%> virginia-small seed 40%순으로 shinpung type이 등숙초기에 건물분배율이 가장 높았다.

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소규모 폐수배출시설 관리 강화의 필요성 (Necessity of Strengthening Small-Scale Wastewater Discharge Facilities Management)

  • 박재홍;류덕희
    • 한국물환경학회지
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    • 제34권2호
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    • pp.226-233
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    • 2018
  • Small-scale wastewater discharge facilities account for 98% of all workplaces, but in the generation and emission of major pollutants, they account for 27.5 % and 23.5 %, respectively. Since the proportion of the emission load of the small-scale workplace is not large, the national environmental policy has been established mainly around large-scale wastewater discharge facilities. However, in the case of specific hazardous substances in water, the amount of the discharge load of the small-scale wastewater discharge facility was 2.4 times higher than that of the generation load. Certain types of specific hazardous substances in water, which have a higher discharge load than large-scale wastewater discharge facilities, account for 24 ~ 32 %. There are also cases in which the discharge load from a small-scale discharge facility is more than four times higher, depending on the specific kind of water pollutant. As a result of inspections, the violation rate of the small-scale wastewater discharge facility among the total violations by facilities is 93.9 ~ 97.5 %. As a result, the ecotoxicity value of small-scale wastewater discharge facilities was high in most industries, and there was a fluctuation in the measured value. This indicates that the ecological integrity of the water system can be largely influenced by small-scale wastewater discharge facilities. Therefore, it is necessary to expand the environmental management of small-scale wastewater discharge facilities, and in some cases, the effect of the improvement in quality may be more significant than in the management of large-scale wastewater discharge facilities.

중소기업의 자동화 생산 정보 플랫폼 구축 모델 설계 (Designing an Automated Production Information Platform for Small and Medium-sized Businesses)

  • 정윤수;김용태;박길철
    • 융합정보논문지
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    • 제9권1호
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    • pp.116-122
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    • 2019
  • 최근 중소기업은 세계적인 경쟁력을 갖추기 위해서 공정/품질/에너지 데이터 집계가 자동 또는 실시간으로 처리할 수 있는 산업 구조로 급격하게 변화하고 있다. 특히, 중소기업 생산 공정에서 생산되는 실시간 정보 분석은 중소기업의 유의미한 성과들을 분석, 예측, 처방 및 이행하는 새로운 공정 프로세스 형태로 진화해 가고 있다. 본 논문에서는 중소기업에서 생상되는 데이터를 고도화할 수 있도록 중소기업의 자동화 생산 정보 시스템을 빅데이터화 할 수 있는 플랫폼 구축 모델을 제안한다. 제안 모델은 스마트한 중소기업의 데이터 수집을 위해 중소기업에서 생산되는 제품의 기본 정보에 대한 다양한 데이터를 활용해 중소기업의 운영 효율화(컨설팅 및 교육 등) 및 전략적 의사결정을 지원할 수 있는 기능이 있다. 또한, 제안 모델은 종소기업의 정보 공유 및 시스템 연계가 원활하게 서로 다른 지역적 특성 및 분야를 가지는 중소기업들간에 긴밀한 협조가 가능한 것이 특징이다.

소수력 발전시스템 무인화 개발

  • 박봉일;박완순;박준식
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2006년도 추계학술대회
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    • pp.511-514
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    • 2006
  • 1. 소수력 발전시스템의 자동화 및 고장진단 알고리즘, 2. 종합 제어시스템의 성능 실험과 원격제어 시스템의 개발, 3. 소수력 발전 시스템의 무인 종합 제어시스템 개발

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선박 TRIM변화에 따른 조종성능의 분석 (The Analysis of the Ship's Maneuverability According to the Ship's Trim and Draft)

  • 박병수;강동훈;강일권;김현무
    • 수산해양교육연구
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    • 제27권6호
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    • pp.1865-1871
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    • 2015
  • Ship's trim is the one of the most important factor for safety at the sea. Turning circle test and Z-test were carried out to find the effect of ship's trim and draft changes. The results are as follows. 1. If the ship's draft and trim became large, turning circle would be wide. 2. If the ship's draft and trim became large, ship's drift angle would be small. Small drift angle made wide turning circle. 3. Trim by the head made slow ship's final speed when turning circle test. 4. By Z-test, the deeper draft and trim by the stern made small OSA. Small OSA means strong ship's stability. 5. Totally 2nd OSA is smaller than 1st OSA on Z-test. 6. There were small differences of 2nd OSA in trim by the stern, but there were large OSA in trim by the head. 7. The larger trim by the stern, the smaller OSW. The small OSW means better ship's stability and maneuverability.

샛강 생태복원을 위한 해외 사례 연구의 고찰 (An Analytical Study of Foreign Researches and Examples on Ecological Restoration for the Small Stream)

  • 권태호;박재현;김동욱
    • 한국환경복원기술학회지
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    • 제7권5호
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    • pp.26-37
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    • 2004
  • Most domestic small rivers and streams due to industrialization and urbanization have managed by concrete structures. The environmental functions of the river and stream are disappearing and urban streams play only the role of drainage systems. Also, the researches to restore natural streams are something yet to develop and not established the restoration for ecological functions of a small stream. Therefore the researches are required to develop ecological engineering system for watershed management system to handle various pollutants with restoration for ecological functions of a small stream. To develop this, the ecological engineering system for watershed management system could be developed with ecological conservation. In addition, ecological engineering system for watershed management system should be prior to conserve the habitat of biological resources and water conservation and applied to the original shape of streams. Also, it should be designed to restore the micro-topography of stream, the habitat of plant population in watershed. It is needed to develop the integrated researches to restore a small stream ecosystem.

작은도서관의 효과적인 운영방안에 관한 연구 - 경기도 지역을 중심으로 - (A Study on the Effective Management Plan for Small Libraries: Focus on Gyeonggi Province)

  • 유양근;박송이
    • 한국비블리아학회지
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    • 제21권1호
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    • pp.175-192
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    • 2010
  • 본 연구는 지방자치단체의 "작은도서관 설치 및 운영 지원에 관한 조례"에서 규정한 작은도서관의 시설규정과 운영방식을 분석하고, 현재 작은도서관을 이용하고 있는 이용자들을 대상으로 서비스에 대한 만족도와 요구들을 조사, 분석하여 작은도서관의 효과적인 운영방안을 제시하는데 그 목적이 있다. 연구방법으로는 단행본 논문 법률자료 인터넷사이트 등을 이용한 문헌연구법과 만족도조사를 통한 설문지법을 병행하였다. 연구결과로 작은도서관의 효과적인 운영방안을 시설 자료 인력 프로그램 네트워크의 다섯 가지 영역으로 구분하여 제안하였다.

강소농 육성사업 참여농가의 성과 만족도 분석 (The Effects of Strong Small Farm Policy for Participation Farms)

  • 박종훈;이성우
    • 농촌계획
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    • 제20권3호
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    • pp.89-100
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    • 2014
  • The purpose of this study is to investigate whether the effect of the Strong Small Farm Development Project by Rural Development Administration is positively associated with participating farmers. The data that used in this study is a survey data that targets 442 farming households who have participated in the strong small farm development project. This study applies ordered-probit model to evaluate level of the participants' satisfaction of the project. This study found that participants' level of satisfaction is closely associated by satisfaction level of project contents that contains education and consulting, friendly attitude toward the project, active participation of the project, and understanding of the project's contents and their importances. Based on research findings, this research provides some implications of future upbringing policy for strong small farms and the principal point of the policy that leads to succeed in implementing the project when formulating agricultural policy in participants view. the strong small farms.