• Title/Summary/Keyword: investigation reports

검색결과 554건 처리시간 0.025초

한국 생물과학자들의 비공식 커뮤니케이션(I) (Informal Communication among Korean Biological Scientists)

  • 조명희
    • 정보관리학회지
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    • 제4권1호
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    • pp.87-101
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    • 1987
  • 본 조사는 한국 생물과학분야 과학자들의 커뮤니케이션 관계에 근거한 사회적 조직을 규명하며, 그들의 정보교환 행태를 분석함을 목적으로 한다. 사회계량적 조사방법을 사용한 결과, 74%의 과학자들이 한개의 큰 네트워크를 형성하며, 생산성이 높고 의사 소통량이 많은 대부분의 과학자가 이에 포함되었다. 많은 접촉을 받은 중심인물들은 정보유통의 중앙 지점에 위치하며, 중요 정보원들임과 동시에 정보 생산자들이다.

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Quantitative and qualitative analysis of autophagy flux using imaging

  • Kim, Suree;Choi, Soohee;Kang, Dongmin
    • BMB Reports
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    • 제53권5호
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    • pp.241-247
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    • 2020
  • As an intracellular degradation system, autophagy is an essential and defensive cellular program required for cell survival and cellular metabolic homeostasis in response to various stresses, such as nutrient deprivation and the accumulation of damaged organelles. In general, autophagy flux consists of four steps: (1) initiation (formation of phagophore), (2) maturation and completion of autophagosome, (3) fusion of autophagosomes with lysosomes (formation of autolysosome), and (4) degradation of intravesicular components within autolysosomes. The number of genes and reagents that modulate autophagy is increasing. Investigation of their effect on autophagy flux is critical to understanding the roles of autophagy in many physiological and pathological processes. In this review, we summarize and discuss ways to analyze autophagy flux quantitatively and qualitatively with the use of imaging tools. The suggested imaging method can help estimate whether each modulator is an inhibitor or a promoter of autophagy and elucidate the mode of action of specific genes and reagents on autophagy processes.

고유진동수를 이용하여 압축력이 작용하는 철골 부재의 구조계 추정 (System identification of steel member acting compressive force using natural frequency of vibration)

  • 심학보;박수용;박효선
    • 한국방재학회:학술대회논문집
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    • 한국방재학회 2007년도 정기총회 및 학술발표대회
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    • pp.45-48
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    • 2007
  • The aim of this study is to estimate the compressive force of steel member using a system identification technique with vibration measurements. To date, several methods have been presented to estimate the compressive force using static and/or dynamic responses of the steel member. However, each and every one of these methods has its disadvantages as well as advantages in its procedures, level of accuracy, and equipment requirements. The paper reports a qualitative investigation of vibration under monoharmonic excitation. The methodology utilizes the relationship between the natural frequencies, the structural parameters, and the compressive force of the member. In this paper, experimental results are presented with a steel beam subjecting to several compressive forces and the proposed method is validated using both numerical and experimental data.

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수도권 전압안정도 향상을 위한 100MVA STATCOM 위치선정 연구 (The Site Selection of 100MVA STATCOM for Voltage Stability Enhancement in Korean Metropolitan Area)

  • 장병훈;김수열;한정열;최돈근;송화창;이병준
    • 전기학회논문지
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    • 제56권9호
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    • pp.1543-1548
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    • 2007
  • This paper reports a study on determination of the adequate location of 100 MVA STATCOM regarding the transfer capability enhancement on the metropolitan interface as well as the economy in system operation. The base case in the study was established considering a scenario of the energy support to North Korea from the KEPCO (Korea Electric Power Corporation) system through a HVDC interconnection. In the base case, the energy support was approximately modeled with a load of 1500 MW, and by the load addition, the system was weakened in terms of voltage stability and transfer capability. After a thorough investigation on the case, the location of the STATCOM was decided to compensate the reactive deficit of the modified system and to maximize the operational benefit which can be estimated by FV analysis.

입구 안내익 영향으로 인한 원심 압축기 성능특성 시험연구 (Experimental Study on the Effect of Inlet Guide Vane of a Centrifugal Compressor)

  • 차봉준;박종호
    • 한국유체기계학회 논문집
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    • 제5권3호
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    • pp.46-53
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    • 2002
  • This paper reports an experimental investigation on a centrifugal compressor with the adjustable inlet guide vane. The compression system is composed of a radial impeller, a vaneless diffuser, and an IGV. The results have shown that surge line on the performance map is affected by the amount of prewhirl and the prewhirl has an effect on transient region between rotating stall and surge. The surge lines have been shifted toward the lower flow region with the increased positive prewhirl and the higher flow region with the increased negative prewhirl. During the unsteady performance test, it was also found that the transient region was reduced with the increased negative prewhirl, and weak signals of rotating stall were detected just before surge as the positive prewhirl was increased.

크랭크 오프셋 엔진의 마찰 특성 : 이론적 고찰 (The Friction Characteristics of Crank Offset Engine : Theoretical Investigation)

  • 조명래;오대윤;김중수;하경표
    • 대한기계학회논문집A
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    • 제26권8호
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    • pp.1591-1598
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    • 2002
  • This paper reports on the effects of crankshaft offset on the engine friction. The effects of crank offset are investigated through the theoretical analysis. In this study, the mathematical models are presented fer evaluationg the friction level of each engine parts. Crank offset influences on the side force acted on the piston pin and sliding speed of piston. Crank offset is very effective to reduce the piston skirt friction. With application of crank offset, total engine friction decreases at low engine speed, but that increase as engine speed increases.

Prevention of Diapause in Bivoltine Eggs of the Silkworm, Bombyx mori, L., through a Cross with the Race KS-10 as Male Parent

  • Mundkur, Rajendra;Murthy, Mallesha;Mahadevappa;Raghuraman, R.;Bongale, U.D.
    • International Journal of Industrial Entomology and Biomaterials
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    • 제9권1호
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    • pp.107-109
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    • 2004
  • The present investigation reports a phenomenon hitherto unknown in tropical sericulture, wherein dia-pause nature of bivoltine eggs is overcome through a cross with a non-diapausing race of silkworm, Bombyx mori, L. Eggs of bivoltine silkworm Bombyx mori, L. generally do not hatch under tropical conditions. To prevent diapause, they are subjected to acid treatment or low temperature hibernation scheduled. A race developed at KSSRDI is found to prevent the diapause nature of bivoltine eggs when crossed as male parent, without any acid treatment or hibernation schedule. This phenomenon is reported for the first time, being unique, opens up interesting area of research in silkworm genetics of commercial implications in the industry.

EVALUATION OF NIRS FOR ASSESSING PHYSICAL AND CHEMICAL CHARACTERISTICS OF LINEN WEFT YARN

  • Sharma, Hss;Kernaghan, K.;Whiteside, L.
    • 한국근적외분광분석학회:학술대회논문집
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    • 한국근적외분광분석학회 2001년도 NIR-2001
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    • pp.1091-1091
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    • 2001
  • Previous reports have shown that Near Infrared Spectroscopy (NIRS) can be used to assess physical and chemical properties of flax fibre and fabric quality. Currently, spinners assess yarn quality mainly based on strength and regularity measurements. There two key characteristics are influenced by quality of raw fibres used, especially the degree of rotting and strength. The aim of this investigation was to evaluate the use of NIRS for assessing quality of weft grade yarn available on the commercial market. In order to develop the NIR calibrations, a range of samples representing poor, medium and good quality weft yarn samples was included in the calibration and validation sample sets. The samples were analysed for physical and chemical parameters including caustic weight loss, fibre fractions, lipid, ash and minerals. A detailed protocol for assessing yarn quality has been developed to maximize the accuracy of the reflectance spectra. The development of partial least squares regression models and validation of the calibration equations using blind samples will be presented and discussed.

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Theoretical Investigation of the Triphosphate Forms of Azidothymidine and Thymidine

  • Arissawa, Marcia;Felcman, Judith;Herrera, Juan Omar Machucca
    • BMB Reports
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    • 제36권3호
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    • pp.243-250
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    • 2003
  • In this paper we investigate (using AM1 semi-empirical as well as HF methods at the STO-3G, 3-21G, 6-31G, 6-$31G^*$ and 6-31+$G^{**}$ level) the conformations, geometrical parameters, Mulliken charges, and solvation effects of the triphosphate form of AZT (AZTTP), as well as the thymidine nucleotide (dTTP) structure. Our calculated geometrical parameters and Mulliken charges, with and without solvation effects, are correlated with recent experimental results.

고속도로 교량국조물의 통행차량에 의한 충격계수 산정방법 개발 (Development for Determining Impact Factor with Respect to Traffic Loads of Highway Bridges)

  • 구봉근;신재인;류택은;이재범;류연종
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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    • pp.809-814
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    • 2001
  • In this paper, dynamic properties of a bridge by traffic loads, is proposed as a reasonable method for the determining the impact factor. In addition, impact factors obtained from previous inspection reports were classified by the span length of the bridge, kind of the bridge and type of the bridge and adjusted the result of the impact factor by the statistical method and presented problems. Also, the determining method of the impact fatter using traffic load is proposed and compared the proposed method with the specification code. The method estimating the impact factor by the traffic loads can be efficiently concluded to the response of structure as reflecting the impact factor and saving the investigation cost. Also it is expected to use to maintenance of structures using the usual test of the bridge.

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