• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.621-622
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• 2008

This paper deals with the magnetic properties under the rotational magnetic field on the electrical steel sheet by using Single Sheet Tester with two excitation coils. Actually, the magnetic flux of stator cores in running motors have the behaviour of rotating and alternating flux. In order to improve motor characteristics, it is require to estimate these magnetic properties. When the magnetic field vectors are rotating around in the plane of the sheet during one period of cycle, the magnetization properties and the core loss are measured and then, the results are compared with the magnetic properties obtained by the alternating magnetic fields.

• Journal of Magnetics
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• 제19권2호
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• pp.155-160
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• 2014

The heating produced by the absorption of radiofrequency (RF) has been considered a secondary undesirable effect during MRI procedures. In this work, we have measured the power absorbed by distilled water, glycerol and egg-albumin during NMR and non-NMR experiments. The samples are dielectric and examples of different biological materials. The samples were irradiated using the same RF pulse sequence, whilst the magnetic field strength was the variable to be changed in the experiments. The measurements show a smooth increase of the thermal power as the magnetic field grows due to the magnetoresistive effect in the copper antenna, a coil around the probe, which is directly heating the sample. However, in the cases when the magnetic field was the adequate for the NMR to take place, some anomalies in the expected thermal powers were observed: the thermal power was higher in the cases of water and glycerol, and lower in the case of albumin. An ANOVA test demonstrated that the observed differences between the measured power and the expected power are significant.

• Earthquakes and Structures
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• 제22권1호
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• pp.65-82
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• 2022

This paper presents a structural performance assessment of a historical masonry clock tower both using numerical and experimental process. The numerical assessment includes developing of finite element model with considering different types of soil-structure interaction systems, identifying the numerical dynamic characteristics, finite element model updating procedure, nonlinear time-history analysis and evaluation of seismic performance level. The experimental study involves determining experimental dynamic characteristics using operational modal analysis test method. Through the numerical and experimental processes, the current structural behavior of the masonry clock tower was evaluated. The first five experimental natural frequencies were obtained within 1.479-9.991 Hz. Maximum difference between numerical and experimental natural frequencies, obtained as 20.26%, was reduced to 4.90% by means of the use of updating procedure. According to the results of the nonlinear time-history analysis, maximum displacement was calculated as 0.213 m. The maximum and minimum principal stresses were calculated as 0.20 MPa and 1.40 MPa. In terms of displacement control, the clock tower showed only controlled damage level during the applied earthquake record.

• 한국가스학회:학술대회논문집
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• 한국가스학회 1998년도 추계학술발표회 논문집
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• pp.95-101
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• 1998

• 한국신뢰성학회지:신뢰성응용연구
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• 제7권2호
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• pp.73-87
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• 2007

In this paper, based on the American weapon acquisition management framework in DoD Instruction 5000.2 "Operation of the Defence Acquisition System" and the contents of "DoD Guide for Achieving Reliability, Availability, and Maintainability" published by Defense Acquisition University, the kinds and roles of technical reviews are introduced and the identification of RAM related tasks which are performed at levels of technical reviews during acquisition process are considered. And the task allocations for developers, development managers, and users are proposed. Finally the relationships of acquisition management framework, technical reviews and RAM tasks are tabulated.

• 복식문화연구
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• 제23권6호
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• pp.1021-1037
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• 2015

This study analyzed the impact of sense of self-efficacy on job satisfaction and organizational commitment among technical designers in order to acquire information needed for human resources management in the field of technical design. The study was implemented through a normative-descriptive survey method using a questionnaire. The sample consisted of 217 technical designers working at vendors and agents located in Seoul. The results revealed that there were significant differences in the sense of self-efficacy levels among technical designers according to age and work experience. Personal self-efficacy had a positive influence on both intrinsic and extrinsic job satisfaction, but also on affective, continuance, and normative organizational commitment. In addition, personal self-efficacy had a greater influence on extrinsic job satisfaction than social self-efficacy. Both personal and social self-efficacy influenced continuance commitment while there was no relationship between social self-efficacy and affective organizational commitment. However, a clear relationship was found between both social and personal self-efficacy and normative organizational commitment. Nevertheless, social self-efficacy had a greater influence on normative organizational commitment than personal self-efficacy. This fact demonstrates the need to exert more effort to promote the sense of personal self-efficacy of technical designers. These results could be used to provide appropriate proposals for human resources management in the field of technical design.

• 농업과학연구
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• 제48권4호
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• pp.729-738
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• 2021

The purpose of this study was to suggest an improvement plan ultimately to develop practical evaluation methods for national technical qualifications in the field of seeds and horticulture based on the National Competency Standards. Through this, national technical qualifications can be strengthened in terms of professionalism in the seeds and horticulture field. In order to conduct this study, the national technical qualification currently in use was matched to certain competency units and competency unit elements of National Competency Standards. We then visited an industrial site to understand the practical factors related to the technical, facility and equipment aspects of the seeds and horticulture industrial field, after which a practical evaluation exam was developed. Also, for a feasibility study, a pilot test assessment was conducted for students majoring in seeds and horticulture, with a survey also conducted with field experts and an advisory committee consisting of experts in seeds and horticulture. Based on the results, by suggesting an improvement plan for a practical evaluation method leading to better national technical qualifications in the field of seeds and horticulture, it was shown to be possible to improve knowledge, technical, and literacy aspects. This can lead to the training of outstanding technical professionals. Ultimately, the results here are expected to contribute to the improvement of the seeds and horticulture industry.

• International Journal of Railway
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• 제2권1호
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• pp.1-7
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• 2009

The development of structural solutions for high-speed or very high-speed tracks that minimize total life cycle costs of the system is a key issue to improve the operational profitability of new investments. In opposition to conventional ballasted tracks, slab track solutions can be a cost-effective solution, but only in the cases where the benefits due to the increase in track availability and the reduction of track maintenance offsets its much higher construction costs. In the cases where such investment is not feasible, it is worth to evaluate possible structural improvements to ballasted track that allow reducing its maintenance needs without increasing too much its construction costs. This paper evaluates the design requirements and the impact of improving conventional high-speed ballasted tracks by using a bituminous subballast layer. It is divided into two main parts: first the design requirements of the structural solutions with bituminous subballast and its possible benefits on high-speed track deterioration, and secondly the evaluation of the economic impact, in terms of construction costs, of using this structural solution material in future Spanish high-speed lines.

• 한국IT서비스학회:학술대회논문집
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• 한국IT서비스학회 2006년도 추계학술대회
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• pp.593-599
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• 2006

Including technical device and general information system, the information-technical(IT) system is defined as the technical system for acquiring, processing, storing and transferring information to a person. This paper presents Knowledge-based Heuristic Evolution Model for creating the advanced information-technical system. This Evolution Model is derived from the historical review on definition of evolution, the research on the architecture of the general IT system, history of IT system, technology innovation theory and multi-case study research. The evolution model is applicable to the conceptual creation of the advanced product in R&D organization requiring development methodologies like rapid-prototyping to develop next generation product. For the detailed theoretical construction and practical application of Evolution Model, the case study research based on action research is performed. the object of the case study is mobile device, especially mobile hand-held phone. Thus, we obtain the Evolution Model for creating the advanced information-technical system.

• 한국건축시공학회지
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• 제21권5호
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• pp.469-481
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• 2021

공사금액 1억이상 120억 미만 중·소규모 건설현장은 전문지도기관의 기술지도를 받아야 한다. 최근 기술지도의 계약 주체가 시공자에서 발주자로 변경됨에 따라 예상되는 기술지도 부실을 방지하기 위해 기술지도 대가를 산정하는 방법을 제안하였다. 대상 건설공사를 공사금액에 따라 4개 구간으로 단순화하고, 구간별 기술지도 담당자의 일 지도횟수와 기술지도 담당자의 최소 기술 등급을 제한하고 엔지니어링사업대가를 적용하여 기술지도 1회당 대가를 산정하는 방법을 제안하였으며, 제안 방법은 설문에서 도출된 현재 형성된 일반적인 대가와 K2B 분석 결과 등을 잘 반영하므로 기술지도 대가 가인드라인 수립에 적용될 수 있다고 판단된다.