• 제목/요약/키워드: investigation reports

검색결과 554건 처리시간 0.034초

P-Δ 효과에 의한 철골 라멘 하부층 변형집중현상 억제를 위한 SM570TMC 고강도강 혼용 사용 설계제안 (Proposal of the Structure Design using SM570TMC for Preventing Deformation Concentration by P-Δ Effect on Lower Story in Steel Ramen)

  • 김문정
    • 복합신소재구조학회 논문집
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    • 제3권3호
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    • pp.31-37
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    • 2012
  • Under the huge seismic loads, there are too many risks about which high-rise buildings lost their lateral stiffness caused by plasticity on frame members. Because of earthquake is important cause to bring the collapes countinue to human's life, many reports examined these phenomenons in various angles. And some of them reported the high possibility about building collapse by deformation concentrations under huge earthquakes. For preventing these phenomenons, researchers suggest some items-such as adding damping devices or strengthen their ductility or stifness. This report suggests choose the method of strengthen building stiffness and suggests the alternative designs using high strength steel-SM570TMC, and provides the results of time-history analysis about the alternative designs for investigation.

조직적 관점에서의 도서관 유효성에 관한 연구

  • 윤혜영
    • 한국도서관정보학회지
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    • 제29권
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    • pp.1-25
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    • 1998
  • Effectiveness is a major concern in organizations of all sorts. Library researchers have been particularly active recently in trying to define, measure, and promote library effectiveness. The purpose of this study is to place library effectiveness in the context of theoretical and empirical work on organizational effectiveness. Four major approaches to organizational effectiveness can be identified. The goal model defines an effective organizations as one that meets its goals. The system resource model emphasizes the organization's need to acquire resources from its environment. The process model sees organizations as social systems seeking to survive and maintain their equilibrium. The multiple constituencies defines effectiveness as the degree to which the needs and expectations of strategic constituencies are met. These models are not necessarily contradictory but may be seen as emphasizing different aspects of organizational performance or values. This study also reports four findings of the library effectiveness. They are significant as the empirical investigation into the dimensions of the construct of library effectiveness. The result shows that organizational effectiveness of libraries is, indeed, a multidimensional construct, implying that no single measure of effectiveness is sufficient to describe an organization.

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Intramolecular Hydrogen Bonds in Proteinase Inhibitor Protein, A Molecular Dynamics Simulation Study

  • Chung, Hye-Shin
    • BMB Reports
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    • 제29권4호
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    • pp.380-385
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    • 1996
  • Ovomucoid third domain is a serine proteinase inhibitor protein which consists of 56 amino acid residues. A fifty picosecond molecular dynamics (MD) simulation was carried out for ovomucoid third domain protein with 5 $\AA$ layer of water molecules. A comparison of main chain atoms in the MD averaged structure with the crystal structure showed that most of the backbone structures are maintained during the simulation. Investigation of the intramolecular hydrogen bondings indicated that most of the interactions between main chain atoms were conserved, whereas those between side chains were reorganized for the period of the simulation. Especially, the side chain interactions around the scissile bond of reactive site P1 (Met18) were found to be more extensive for the MD structures. During the simulation, hydrogen bonds were maintained between the side chains of Glu19 and Arg21 as well as those of Thr17 and Glu19. Extensive side chain interactions observed in the MD structures may shed light on the question of why protein proteinase inhibitors are strong inhibitors for proteinases rather than good substrates.

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Investigation of Charge Transfer between Graphene and Oxide Substrates

  • Min, Kyung-Ah;Hong, Suklyun
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.186.1-186.1
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    • 2014
  • Graphene, which is a 2-dimensional carbon material, has been attracting much interest due to its unique properties and potential applications. So far, many interesting experimental and theoretical works have been done concerning the electronic properties of graphene on various substrates. Especially, there are many experimental reports about doping in graphene which is caused by interaction between graphene and its supporting substrates. Here, we report the study of charge transfer between graphene and oxide substrates using density functional theory (DFT) calculations. In this study, we have investigated the charge transfer related with graphene considering various oxide substrates such as SiO2(0001) and MgO(111). Details in charge transfer between graphene and oxides are analyzed in terms of charge density difference, band structure and work function.

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Reynolds Number를 변수(變數)로한 유동공기(流動空氣)의 방전특성(放電特性)에 관한 연구 (Characteristics of Sparkover Discharge in Flowing Air with Reynolds Numbers' Variable)

  • 김영훈;오재열;이광식;이동인
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1990년도 하계학술대회 논문집
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    • pp.286-288
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    • 1990
  • This paper reports the characteristics of sparkover discharge in flowing air ranging from 0[m/s] to 30 [m/s] under the needle-needle gap. Flowing air duct of this investigation is circular tube. The important results obtained form this study are as follows. 1. the ratio of sparkover voltage to the Reynolds number decreases with increasing the Reynolds number. 2. The duration time of sparkover(t) decreases with increasing the Reynolds number. 3. the empirical equation obtained form this experiment is [ %]${\frac{Vs}{Re}}$ = A + $B{\varepsilon}^{C.Re}$ where A = 10.2 b = 125 c = -4.66 ${\times}$ $10^{-5}$

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동압밀공법을 이용한 지반개량 사례연구 (EFFECTIVENESS ANALYSIS OF GROUND IMPROVEMENT TREATED BY DYNAMIC CONSOLIDATION)

  • 양정수;손준익
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 1992년도 가을학술발표회 논문집
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    • pp.137-144
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    • 1992
  • This paper reports a case study of dynamic consolidation. The objective of the study is to evaluate the effectiveness of ground improvement at the site for Hyundai Petrochemical Compound constructed at Daesan-Myeon, Seosan-Gun in the western shores of Korea. The site ground was prepared by filling on the existing soft marine deposit which consists of a loose granular soil layer and a medium stiff clay layer. For the stabilization of site ground, the compaction was executed in three different procedures with same pounder weigh, drop height and imprint spacing. The post investigation showed that the object was successfully achieved indicating a significant increase of bearing capacity of the treated ground. In this study the effectiveness of dynamic consolidation is evluated for various factors the applied energy, temping sequences, the radial distance from the imprint location and the depth of bed rock.

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BRIEF REPORTS ON KAISTSAT-4 MISSION ANALYSIS

  • Seon, J.
    • Journal of Astronomy and Space Sciences
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    • 제17권2호
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    • pp.233-240
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    • 2000
  • Five scientific instruments are planned on KAISTSAT-4 that is scheduled to be launched in 2002. A far ultra-violet imaging spectrograph and a set of space plasma instruments are currently being designed. The imaging spectrograph will make observations of astronomical objects and Earth's upper atmosphere. The plasma instrumentation is capable of fast measuring the thermal magnetosphere plasmas, cold ionospheric plasmas and the Earth's magnetic fields. Major system drivers and constraints on the payloads as well as the spacecraft are identified. A preliminary analysis of the K-4 mission has been undertaken with the system requirements that are derived from the system drivers. Detailed investigation shows that Sun-synchronous orbits with approximate altitudes of 800km are optimal to satisfy the identified requirements. Comparisons with other orbits of different inclinations are also shown. Four operation modes and a daily schedule of spacecraft maneuver are found from the Sun-synchronous orbital model. It is shown that the scientific objectives of K-4 can be achieved with moderate levels of design and operation risks.

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열교환기에서의 유동유발 진동 저감 (Reduction of Flow-Induced Vibration in the Heat Exchanger)

  • 장한기;김승한;이재현;양정렬
    • 소음진동
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    • 제9권6호
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    • pp.1200-1209
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    • 1999
  • This paper reports a peculiar example of flow-induced vibration in a very large plant and the whole procedure of reducing the vibration. During the operation of flue gas desurfurization unit of the thermal power plant, serious vibration was dtected at all around the plant. The worst vibration was recorded on the heat exchanger surface, which weighed 180 tones, as 17.8 m/$s^2$ in vibration amplitude at 34 Hz. To identify the vibration, frequency analysis on the response vibration as well as on the expected excitation forces and the system resonance was executed. This investigation revealed that the cause of the vibration was vortex shedding from the circular pipes in the heat exchanger. Vortices from the pipes excited acoustic resonance in the heat exchanger room, which, in turn, made the structure vibrate. Through inserting the baffles between the pipes, which had an effect of cutting the acoustic wave at resonance frequency, the vibration was eliminated dramatically.

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Landsat 영상을 이용한 도시확장과 지표온도 변화 탐지 (Detection of urban expansion and surface temperature change using Landsat imagery)

  • 손홍규;곽은주;방수남;박완용
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2004년도 추계학술발표회 논문집
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    • pp.161-166
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    • 2004
  • Seoul has experienced a rapid urban expansion over the past three decades. This paper reports an investigation into the application of Landsat imagery for detecting urban growth and assessing its impact on surface temperature in the region. Land cover/use change detection w3s carried out by using Landsat data. The results revealed a notable urban growth in the study area. This urban expansion had raised surface radiant temperature in the urbanized area. The method using remote sensing data based on GIS was found to be effective in monitoring and analysing urban growth and in evaluating urbanization impact on surface temperature.

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국내 연약 점성토 지반의 지반공학적 특성 (Geotechnical Characteristics of Soft Clayey Soil in South Korea)

  • 오서현;하태균;정충기
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2009년도 춘계 학술발표회
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    • pp.922-929
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    • 2009
  • In this paper, 4 representative soft clayey soils in south Korea are selected to estimate the geotechnical characteristics and provide the instructions avaliable for construction works; Inchon Coast, Kum River Estuary, Kwangyang Bay, and Nakdong River Estuary. Total 2250 boring data are collected to construct the data base system on selected areas from Korea geotech DB system, scientific journals, theses, and site investigation reports. Considering the geological, topographical and regional features, geotechnical properties, deformation and strength characteristics of 4 soft clayey soils are evaluated by analyzing the constructed DB system statistically.

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