• 한국운동역학회지
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• 제16권4호
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• pp.175-187
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• 2006

The purpose of this study was to find the relationship between Achilles tendon angle, angular velocity from 2D cinematography utilized to easily analyze the functions of shoes, ankle joint moment, knee joint moment, and hip joint moment from 3D cinematography utilized to predict the injury. Also, this study was to provide the optimal standard to analyze the injury related to the shoes. Subjects in this study were 30 university male students and 18 conditions (2 types of running speed, 3 of midsole hardness, 3 of midsole height) were measured using cinematography and force platform. The results were as following. 1) Hip joint abduction moment was effected by many variables such as running speed, midsole height, maximum achilles tendon angle, ground reaction force. 2) Knee joint rotational moment in running was approximately 1/10 - 1/4 times of the injury critical value and eversion moment was approximately 1/4 - 1/2 times of the injury critical value. 3) Ankle joint pronation moment in running was 1/3 - 1/2 times of the injury critical value. 4) Knee joint rotational moment was found to be irrelevant with maximum achilles tendon angle or angular velocity. 5) Pronation from running was thought to be relevant to rather eversion moment activity than rotational moment activity of knee joint. 6) Plantar flexion abductor of ankle showed significant relationship with the ground reaction force variable. 7) When the loading rate for ground reaction force in passive region increased, extensor tended to be exposed to the injury. Main variables in biomechanical analysis of shoes were impact absorption and pronation. Among these variables, pronation factor was reported to be relevant with knee injury from long duration exercise. Achilles tendon angle factor was utilized frequently to evaluate this. However, as the results of this study showed, the relationship between these variables and injury relating variable of knee moment was so important. Studies without consideration on this finding should be reconsidered and reconfirmed.

• Steel and Composite Structures
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• 제22권6호
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• pp.1417-1443
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• 2016

Cellular and castellated steel beams are used to obtain higher stiffness and bending capacity using the same weight of steel. In addition, the beam openings may be used as a pass for different mechanical fixtures such as ducts and pipes. The aim of this study is to investigate the effect of different parameters on both elastic and inelastic critical buckling stresses of steel web plates with openings. These parameters are plate aspect ratio; opening shape (circular or rectangular); end distance to the first opening; opening spacing; opening size; plate slenderness ratio; steel grade; and initial web imperfection. The web/flange interaction has been simplified by web edge restraints representing simply supported boundary conditions. A numerical parametric study has been performed through linear and nonlinear finite element (FE) models, where the FE results have been verified against both experimental and numerical results in the literature. The web plates are subject to in-plane linearly varying compression with different loading patterns, ranging from uniform compression to pure bending. A buckling stress modification factor (${\beta}$-factor) has been introduced as a ratio of buckling stress of web plate with openings to buckling stress of the corresponding solid web plate. The variation of ${\beta}$-factor against the aforementioned parameters has been reported. Furthermore, the critical plate slenderness ratio separating elastic buckling and yielding has been identified and discussed for two steel grades of DIN-17100, namely: ST-37/2 and ST-52/3. The FE results revealed that the minimum ${\beta}$-factor is 0.9 for web plates under uniform compression and 0.7 for those under both compression and tension.

• 소성∙가공
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• 제16권4호
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• pp.276-281
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• 2007

The hardening and the constitutive equation based on the crystal plasticity are introduced for the numerical simulation of hemispherical sheet metal forming. For calculating the deformation and the stress of the crystal, Taylor's model of the crystalline aggregate is employed. The hardening is evaluated by using the Taylor factor, the critical resolved shear stress of the slip system, and the sum of the crystallographic shears. During the hemispherical forming process, the texture of the sheet metal is evolved by the plastic deformation of the crystal. By calculating the Euler angles of the BCC sheet, the texture evolution of the sheet is traced during the forming process. Deformation texture of the BCC sheet is represented by using the pole figure. The comparison of the strain distribution and punch force in the hemispherical forming process between the prediction using crystal plasticity and experiment shows the verification of the crystal plasticity-based formulation and the accuracy of the hardening and constitutive equation obtained from the crystal plasticity.

• 한국컴퓨터정보학회논문지
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• 제22권2호
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• pp.111-117
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• 2017

This study analyzes the relative importance of the introducing factors for the critical success factors in the implementation stage of the lifecycle of ERP system using Delphi technique and Analytic Hierarchy Process(AHP). In the 1st layer of the hierarchy, technical factor is evaluated as the most important factor among organizational, technical, and supplier factors. In the 2nd layer, choosing a proper ERP package is evaluated as the most important factor within 15 factors followed by process-oriented approach, technical suitability, minimized customization, integration and association of system with trading parter, association with legacy systems, and support and involvement of top management. As a result of this analysis enterprise should choose an ERP package that is suitable to its business environment, and make the best use of(take full advantage of) best practice that ERP package provides to optimize the existing business procedure or process(to approach the existing business procedure or process). This study also shows the range of customization of the features provided by the ERP package should be minimized.

• 한국건설관리학회논문집
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• 제8권5호
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• pp.182-190
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• 2007

국내 중 소규모 건설 산업은 시공분야를 중심으로 발전하여 왔으며 소프트분야가 상대적으로 취약하다. 또한 다양한 발주 체계가 활용되지 못하는 문제점을 안고 진행되고 있다. 더욱이 현재 국내 건설 프로젝트들은 자금력과 기술력을 갖춘 대형 건설업체들이 경쟁 우위를 점하고 있어 중 소규모 건설업체들의 입지가 줄어들고 있다. 최근국내 외 건설시장의 대형화, 고도화와 함께 기술집약적인 공사가 늘어감에 따라 기술경쟁이 가능한 설계시공일괄(Design-Build)방식의 건설 산업이 늘어나고 있는 추세이며 규모가 작은 중 소건설기업의 상황에서는 더욱 건설시장에서 효과적인 경쟁력을 보유하여야 할 것으로 예상한다. 이에 본 연구는 디자인 빌드 방식의 성공요인과 중 소규모 프로젝트 사례조사를 한 후 AHP 분석을 통해 성공요인 도출 및 중요도 분석을 함으로써 중 소규모 건설업체의 디자인 빌드 방식의 성공적 수행을 위한 중점 관리요인을 제시하고자 한다. 그리하여 향후 중 소 건설업체의 발전과 생산성 향상을 위한 기반을 제공하고자 한다.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2007년도 정기학술발표대회 논문집
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• pp.337-340
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• 2007

건설교통부에서는 건설부문의 정보화를 선도하고자 건설CALS를 시작하였다. 건설CALS는 공공건설부문을 정보화하고 건설인의 정보화마인드 정착에 기여하였으며 투자대비 비용절감 효과도 큰 반면, 시스템의 노후와와 개발한 시스템의 확산전략 미수립 등의 이유로 효과가 반감되고 있다. 현 시점에서 건설CALS의 현주소를 정확히 파악하여 향후 나아갈 바를 정립하고 도입효과를 극대화시킬 필요가 있다. 이에 본 연구에서는 전략을 수립하는데 효과가 있는 SWOT분석 기법을 이용하여 건설CALS가 지향해야 할 핵심성공요인을 제시하였다. 이를 위해 문헌조사를 통해 건설CALS를 둘러싼 내${\cdot}$외부환경을 고찰하여 25개의 강점, 약점, 기회 및 위협요인을 도출하였으며 SO, ST, WO, WT 기본전략을 수립하였다. 최종적으로 전략을 달성하기 위한 14개의 핵심성공요인을 제시하였으며, 제시한 요인의 타당성 확보를 위해 건설 각 분야의 전문가에게 검증하는 절차를 거쳤다. 이 연구에서 제시한 결과들은 향후 건설CALS가 나아갈 이정표를 제시하는데 의의가 있다. 성공요인 달성을 위한 중점 추진분야 선정, 세부연구과제 도출 등의 후속연구가 지속적으로 수행되어야 한다.

• 한국치위생학회지
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• 제19권6호
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• pp.1037-1046
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• 2019

Objectives: This study was conducted to test the critical thinking tendency, clinical practice satisfaction, and clinical performance, and analyze the factors impacting clinical practice satisfaction and clinical performance of dental hygiene students. Methods: The study conducted a written survey during the period between 30 July ~20 August 2019, among 3rd and 4th year dental hygiene students from Seoul, Gyung-gi region, who had taken clinical practice courses. Using SPSS 22.0 program (IBM SPSS statistics, New York, USA), the study analyzed the final 174 cases. Results: Dental hygiene students scored 3.33±0.43, 3.48±0.83, and 3.30±0.58 for critical thinking, clinical practice satisfaction, and clinical performance, respectively. The clinical thinking score was higher when their study performance was good (p<0.001), clinical practice satisfaction was higher when their major satisfaction was satisfactory (p<0.001), higher when their relationship with their clinical practice partner was good, and the clinical performance was better when the students' major satisfaction was good (p<0.001). The study performance yielded better results when their study achievement was better (p<0.05). Clinical practice satisfaction (r=0.156) and clinical performance (r=0.393) showed a positive correlation with critical thinking, and clinical performance had a positive correlation with clinical practice satisfaction. The impact factor for clinical practice satisfaction appeared to be clinical performance (p<0.05) and major satisfaction (p<0.001), and the factors impacting the clinical performance were among the sub-causes of critical thinking (p<0.05), intellectual fairness (p<0.05), watchfulness (p<0.05), clinical practice satisfaction (p<0.05), and major satisfaction (p<0.01). Conclusions: Results of the study showed that for dental hygiene students, critical thinking, clinical practice satisfaction, clinical performance, and major satisfaction were the impact factors affecting the students' clinical performance. Therefore, the study recommends that development of educational programs and operation of a field-based curriculum is necessary to improve critical thinking, clinical practice satisfaction, and major satisfaction.

• 대한기계학회논문집A
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• 제21권10호
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• pp.1609-1618
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• 1997

Thermo-mechanical behaviors of polymer matrix composite(PMC) with continuous TiNi fiber are studied using theoretical analysis with 1-D analytical model and numerical analysis with 2-D multi-fiber finite element(FE) model. It is found that both compressive stress in matrix and tensile stress in TiNi fiber are the source of strengthening mechanisms and thermo-mechanical coupling. Thermal expansion of continuous TiNi fiber reinforced PMC has been compared with various mechanical behaviors as a function of fiber volume fraction, degree of pre-strain and modulus ratio between TiNi fiber and polymer matrix. Based on the concept of so-called shape memory composite(SMC) with a permanent shape memory effect, the critical modulus ratio is determined to obtain a smart composite with no or minimum thermal deformation. The critical modulus ratio should be a major factor for design and manufacturing of SMC.

• Journal of Electrical Engineering and Technology
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• 제13권6호
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• pp.2310-2318
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• 2018

Critical conduction mode (CRM) operation is more efficient than continuous conduction mode (CCM) operation at low power levels because of the valley switching of switches and elimination of the reverse recovery losses of boost diodes. When using a sensorless digital control method, an error occurs between the actual and the estimated current. Because of the error, it operates as CCM or discontinuous conduction mode (DCM) during CRM operation and also has an adverse effect on THD of input current. In this paper, a current sensorless technique is presented in an inverter system using a bridgeless boosted power factor correction converter, and a compensation method is proposed to reduce CRM calculation error. The validity of the proposed method is verified by simulation and experiment.

• The Journal of Asian Finance, Economics and Business
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• 제7권7호
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• pp.391-401
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• 2020

The objective of this study is to prioritize the Total Quality Management (TQM) factors based on fuzzy Analytical Hierarchy Process (AHP) method in Vietnamese supporting industries. Through an in-depth literature review, eight criteria were identified. These criteria were then divided into 32 sub-criteria. The fuzzy AHP is used to determine the percent weightings of eight categories of performance criteria that were identified via a review of the quality-management literature. These criteria include management commitment, role of the quality department, training and education, continuous improvement, quality policies, quality data and reporting, communication to improve quality, and customer satisfaction orientation. An empirical analysis of the criteria of each stage using the fuzzy AHP methodology and the expert opinion of quality management are used to evaluate the percent weightings of the criteria and sub-criteria that are synonymous with TQM implementation. The results showed that management commitment is the most critical factor; among sub-criteria, supports and responsibilities of top management is the most important. The study also identified the rank order of critical success factors of TQM. The findings suggest a generic hierarchy model for organizations to prioritize the critical factors and formulate strategies for implementing TQM in supporting industries, as well as other industries in Vietnam.