• Korean Journal of Applied Biomechanics
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• v.16 no.4
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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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• v.22 no.6
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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.

• Transactions of Materials Processing
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• v.16 no.4 s.94
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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.

• Journal of the Korea Society of Computer and Information
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• v.22 no.2
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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.

• Korean Journal of Construction Engineering and Management
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• v.8 no.5
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• pp.182-190
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• 2007

The minor construction companies in Korea have grown in focusing on the construction operation field. Also, soft field is vulnerable area, and there are not enough delivery systems, therefore, a capacity of the construction industry expansion and productivity is insufficient. Furthermore, the minor construction companies are losing their areas, because the major construction companies having numerous know-how and ample funds are competitive. As the construction industry are more larger and complicated, the design build methods might be increased in the construction industry and the minor construction companies could have more competitive. Hence, this paper analyzes the success factor in minor construction projects by design build methods focusing on instance $company^{\circ}{\phi}s$ case and survey, and critical success factor deduction and importance degree analysis of this factor using AHP analysis. In addition, this paper gives fundamental data how to manage the construction project effectively for minor construction $companies^{\circ}{\phi}s$ expansion in near future.

• Journal of Korean society of Dental Hygiene
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• v.19 no.6
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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.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.337-340
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• 2007

Construction CALS contributed to informatization of public construction sector and to settle construction leaders' mind on informatization of construction project, however, the effect of Construction CALS has reduced as the CALS system has been aged and a plan for spread-out of existing systems has not been established. It is necessary to maximize the effect by developing a future plan after recognizing the current state. This study provided key factors that Construction CALS should take for the bright future by using SWOT Analysis, an useful method to develop a strategy. Considering interior and exterior environments surrounding Construction CALS through investigating existing studies, this study deduced twenty five strength, weakness, opportunity and threat points, and finally this study proposed fourteen critical success factors. The results of this study made a significant contribution to decision of the milestone that Construction CALS should take.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.10
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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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• v.13 no.6
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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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• v.7 no.7
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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.