• 한국문헌정보학회지
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• 제35권4호
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• pp.97-122
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• 2001

본 연구에서는 레코드필드 선택이 대규모 서지 데이터베이스 탐색시 미치는 검색 성능에 대하여 관찰하였다. 실험의 구성 요소는 크게 (1) 대규모 상업용 데이터베이스 INSPEC. (2) 관련된 레코드들 (target sets이라고 정의함). (3) 4개의 키워드가 한 세트로 이루어진 4개의 서로 다른 형태의 질의어들 (CT_TF, CT_IDF, UT_TF, UT_IDF), (4) 최적의 질의를 위한 알고리즘, (5) 가능한 모든 경우의 탐색식을 생성해내는 블리언 탐색식 생성기, 그리고 (6) 실제 운영중인 웹 기반의 검색 시스템으로 이뤄졌다. 실험에서의 레코드 필드 선택은 (1) Abstract, (2) Descriptors, (3) Identifiers, (4) 'Subject'(Descriptors + Identifiers). (5) Title. (6) 'All fields'로 정의하여 독립변수로 채택하였다. 검색 성능은 재현율, 정도율을 모두 반영한 Heine의 D측정에 의하여 평가 되었다. 본 연구에서 얻은 주된 결과로는 (1) 필드선택은 검색성능에 중요한 영향을 미치며, (2) 각 검색 성능에서 보여준 순위는 질의어에 따라 민감한 결과를 보였고 (3) 제목(Title)필드 선택이 D측정에서 최적의 결과를 보였다.

• 한국콘텐츠학회논문지
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• 제22권2호
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• pp.447-456
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• 2022

지난 25년간 우리나라의 자활사업은 저소득 취약계층을 위한 가장 중요한 고용복지정책으로 자리매김 해왔다. 그러나 그간 자활사업 성과지표는 현장성이 부족하다는 지적이 많았는데, 특히 경제적 성과 중심의 지표와 지역유형을 고려하지 않은 일괄적인 적용 방식에 대해 개선이 필요한 상황이다. 이에 본 연구는 ISA 기법을 활용하여, 자활사업 성과지표에 대한 실천현장의 인식을 분석하고, 현장 적합성을 제고하는 지표 개선에의 함의를 도출하고자 하였다. 성과지표의 중요도와 만족도 분석에서는 자활사업의 결과보다 과정에 대한 중요도가 크고, 현행 지표가 현장을 만족스럽게 반영하지 못하는 것으로 나타났다. ISA 매트릭스 분석에서는 유지와 개선, 그리고 정책적 재고를 요하는 성과지표들이 분류되었는데, 이때 도시형과 농촌형의 매트릭스의 차이가 확연히 다른 것들이 발견되었다. 이러한 발견들을 통해 본 연구는 현장 지향성을 가진 성과지표를 제안하고 그 중요성을 강조하고 있어, 향후 성과지표의 개선을 위한 탐색적 기초연구로서의 의의가 있다.

• 대한기계학회논문집B
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• 제25권12호
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• pp.1730-1738
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• 2001

This paper presents an overview of testing and analyzing field performance of a centrifugal chiller which has a rated capacity of 200 RT(703 kW). Field data of a chiller installed in the cleanroom research building of KIST has been collected far performance analysis. The operating data included start-up, shut-down, and quasi-static state where cooling capacity and compressor power consumption varied cyclically. It was found that the steady-state thermodynamic model could be applied to relate the cooling capacity and COP under quasi-static conditions. The results led to finding the required cooling load pattern and a possible energy saving method. This study provides a method of evaluating performance of a large capacity centrifugal chiller in which field test is necessary.

• Steel and Composite Structures
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• 제41권5호
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• pp.713-730
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• 2021

The seismic performance of rigid steel frames is widely investigated, but that of semi-rigid (SR) steel frames are not studied extensively, especially for near-field earthquakes. In this paper, the performances of five and ten-story steel SR frames having different degrees of semi-rigidity are evaluated at four performance points in the four different deformation states, namely, the elastic, elasto-plastic, plastic, and near collapse states. The performances of the SR frames are measured by the response parameters including the maximum values of the top floor displacement, base shear, inter-story drift ratio, number of plastic hinges, and SRSS of plastic hinge rotations. These response parameters are obtained by the capacity spectrum method (CSM) using pushover analysis. The validity of the response parameters determined by the CSM is evaluated by the results of the nonlinear time history analysis (NLTHA) for both near and far-field earthquakes at different PGA levels, which are consistent with the performance points. Results of the study show that the plastic hinges of SR frame significantly increase in the range of plastic to near-collapse states for both near and far-field earthquakes. The effect of the degree of semi-rigidity is pronounced only at higher degrees of semi-rigidity. The predictions of the CSM are fairly well in comparison to the NLTHA.

• Structural Engineering and Mechanics
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• 제8권1호
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• pp.19-26
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• 1999

Superior performance of field consistent eight-node hexahedron element in static bending problems has already been demonstrated in literature. In this paper, its performance in free vibration is investigated. Free vibration frequencies of typical test problems have been computed using this element. The results establish its superior performance in free vibration, particularly in thin plate application and near incompressibility regimes, demonstrating that shear locking, Poisson's stiffening and volumetric locking have been eliminated.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 춘계 학술논문 발표대회
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• pp.194-196
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• 2013

Recently, It is a fact that the percentage of female field managers has increased in the construction industry. Therefore, this study investigated the percentage of female construction site managers by conducting a survey of current male and female construction site managers and then analyzed the workload, work difficulty, work importance and performance level of female employees in charge of public affairs, which is the most common tasks.

• 한국건축시공학회지
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• 제13권5호
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• pp.474-481
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• 2013

The success of a construction project hinges on the effective and efficient management of human resources. The stress of human resources is directly related with work performance, and as such, should be managed to improve work performance. This study examined the correlation between job stress and job satisfaction among building construction project managers. A questionnaire to measure work performance was created by referring to the Korean Occupational Stress Questionnaire Short Form developed by the Korean Occupational Safety & Health Agency, as well as a previous study. The mean job satisfaction score of field managers was 3.6, which suggests that they are generally satisfied in their current job environment. A Pearson's correlation analysis showed that the field managers that were satisfied with their job had less job stress. These results could be used for the effective management of construction site managers and to improve their job performance in the field.

• 산업기술연구
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• 제17권
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• pp.79-85
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• 1997

This paper describes a control for the high performance induction motor drive system with a wide speed operating range and proposes a robust control method independent of motor parameter variation. For the operation below the rated speed, the high performance control is achieved by using the indirect field-oriented control with a speed sensor. In the high speed regain, the field weakening region with a large variation in motor parameters, the motor drive system can obtain the robustness to motor parameter variation by switchover to the direct field-oriented control. Also, the sensorless speed control using estimated speed is achieved in very high speed region that the utilization of speed sensor pulses is limited. And from experiments using high performance 32bit DSP for 2.2[kW] and 22[kW] laboratory induction motor drive systems, it is verified that the proposed opration algorithm provided a good performance.

• Coupled systems mechanics
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• 제12권2호
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• pp.167-181
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• 2023

The determination of the blast protection level and the corresponding minimum load-bearing capacity for a laminated glass (LG) window is of crucial importance for safety and security design purposes. In this paper, the focus is given to the window response under near-field blast loading, i.e., where relatively small explosives would be activated close to the target, representative of attack scenarios using small commercial drones. In general, the assessment of the load-bearing capacity of a window is based on complex and expensive experiments, which can be conducted for a small number of configurations. On the other hand, nowadays, validated numerical simulations tools based on the Finite Element Method (FEM) are available to partially substitute the physical tests for the assessment of the performance of various LG systems, especially for the far-field blast loading. However, very little literature is available on the LG window performance under near-field blast loads, which differs from far-field situations in two points: i) the duration of the load is very short, since the blast wavelength tends to increase with the distance and ii) the load distribution is not uniform over the window surface, as opposed to the almost plane wave configuration for far-field configurations. Therefore, the current study focuses on the performance assessment and structural behaviour of LG windows under near-field blasts. Typical behavioural trends are investigated, by taking into account possible relevant damage mechanisms in the LG window components, while size effects for target LG windows are also addressed under a multitude of blast loading configurations.

• 한국사회복지학
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• 제56권3호
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• pp.327-355
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• 2004

본 연구에서는 직접실천기관에서 실습을 이수한 재학생을 대상으로 실습지도 실태 및 실천수행능력에 영향을 미치는 요인을 조사하였다. 조사결과, 첫째, 수퍼비전 정도는 4점 척도에서 평균 2.6(표준편차 .5), 실천수행능력은 11점 척도에서 평균 56.7(표준편차 1.7)점으로 나타나, 모두 거의 중간수준으로 응답했으며, 수퍼비전 요인 가운데 이론과 실천의 통합에 대한 지도와 지지적인 사적 관계 형성 요인이, 그리고 실천수행능력 요인 가운데 개입기술 능력과 사례관리 능력 요인이 상대적으로 낮게 나타났다. 둘째, 수퍼비전과 실천수행능력의 요인들간의 상관관계는 모두 유의미한 것으로 나타났다. 셋째, 실천수행능력은 수퍼비전 요인 가운데서도 이론과 실천의 통합에 대한 지도가 많을수록, 기관 업무에 대한 지도가 많을수록, 학습계약에 대한 논의를 많이 하고 수퍼비전 시간이 많을수록 증가되는 것으로 나타났다. 이외에 실습생이 여성일 경우, 그리고 수퍼바이저의 수퍼바이저로서의 경력이 적을수록 실천수행능력이 높게 나타났다. 이러한 연구결과를 토대로 대학과 기관에서 협력하여 실습지도를 효과적으로 운영하기 위한 제언을 하였다. 또한 궁극적으로 사회복지 교육의 효과성을 제고하기 위한 연구 및 노력의 필요성을 제기하였다.