• Journal of the Korean Geotechnical Society
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• v.15 no.2
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• pp.29-42
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• 1999

The SASW (Spectral-Analysis-of-Surface-Waves) method, which evaluates the stiffness structure of the subsurface and structures nonintrusively and nondestructively, has been successfully used in the civil engineering applications. However, the SASW method assumes that the subsurface or structures consist of horizontal multi-layers, so that the method has some difficulty in continuously evaluating the integrity of a tunnel lining and a pavement system. This difficulty prevents the SASW method from being used to generate a tomographic image of stiffness for the subsurface or structures. Recently, the GPR technique which has the advantage of continuously evaluating integrity of the subsurface and structures has been popular. This advantage of GPR technique initiated the efforts to make the SASW method, which is superior to GPR and other nondestructive testing methods due to its capability of evaluating stiffness and modulus, be able to do continuous evaluation of stiffness structure, and the efforts finally lead to the development of \ulcornerTomographic SASW Technique.\ulcorner Tomographic SASW technique is a variation of the SASW method, and can generate a tomographic image of stiffness structure along the measurement line. The tomographic SASW technique was applied to the investigation of lateral variability of a sand box placed by the raining method for the purpose of verifying its effectiveness. Tomographic SASW measurements on the sand box revealed that the investigated sand box has different shear stiffness along the measurement line, which gave a clue of how to make a better raining device.

• Journal of Digital Convergence
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• v.14 no.5
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• pp.527-539
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• 2016

The purpose of this study is to examine the structural relationship among professionalism of sport instructors, job burnout and turnover intention. Independent variable was professionalism of sport instructors, mediating variable was job burnout. Finally, dependent variable was turnover intention. The data were collected from 253 sport instructors of elementary school by the convenience sampling method. This study used IBM SPSS Ver. 20.0 and AMOS 18.0 for frequency analysis, reliability, correlation analysis, confirmatory factor analysis and structural equation model. After confirming the test of goodness of fit of a model, individual hypotheses was verified. The results were as follows; First, Professionalism had a significant influence on job burnout. Second, Job burnout had a significant influence on turnover intention. Third, Professionalism did not have a significant influence on turnover intention.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.6A
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• pp.327-336
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• 2012

This study presents the effects of various geometric properties on the ultimate behavior of steel cable-stayed bridges. In general, cable-stayed bridges are well known as a very efficient structural system, because of those geometric characteristics, but at the same time, the structure also shows complex structural behavior including various nonlinearities which significantly affect to the ultimate behavior of the structure. In this study, the effects of various geometric properties of main members on the ultimate behavior under specific live load cases, which had been studied in previous studies, were investigated using a rational analytical method. In this parametric study, sectional dimensions of main members were considered as main geometric parameters. For the rational ultimate analysis under specific live load cases, the 2-step analysis method, which contains initial shape analysis and live load analysis, was used. As the analysis model, 920.0 m long steel cable-stayed bridges were used and two different types of cable arrangement were considered to study the effect of the cable arrangement types. Through this study, the effects of various geometric properties on the characteristics of the ultimate behavior of steel cable-stayed bridges were intensively investigated.

• Journal of the Korean GEO-environmental Society
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• v.7 no.3
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• pp.69-76
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• 2006

In this study, an experimental study in sand ground that was prepared by raining method was performed for modeling the bearing capacity behavior of strip footing above a cavity. The critical range of bearing capacity of the strip footing affected by underground cavity was investigated by comparing results between experiment and theory. The size of the critical region depends on several factors such as footing shape, soil property, cavity size and cavity shape. The ultimate bearing capacity was more influenced by the depth of the underground cavity than the eccentricity of the underground. In addition, an underground cavity influences on not only the decrease of the bearing capacity, but also the differential settlement of a strip footing.

• Journal of Practical Engineering Education
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• v.13 no.3
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• pp.545-558
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• 2021

As the "Partial Amendment to the Vocational Competency Development Act" was passed, and the mandatory refresher training was legislated in March 2020, HRD education institutions has prepared a plan for the improved refresher training to strengthen the competency of vocational training teachers and to improve the quality of refresher training. However, as demand for refresher training is concentrated in partial occupations, it is necessary prepare a separate plan to recognize personal learning as a refresher training for a minority of teachers who are not provided with a training. Therefore, this study aims to identify areas of a minor training occupations that don't exist many participants for a refresher training and to derive ways to recognize their multiple education experiences and participations instead of attending a refresher training. To this end, literature review, analysis of current situation, consultation with stakeholders, and written interviews with experts were conducted. As a result, a minority of training occupations was defined as type 1 and type 2 and ways of the recognition of refresher training for minority of training occupations which embrace various educational types were derived. Lastly, discussions and suggestions on the expansion of the scope of the recognition of refresher training for minority of training occupations were provided.

• Journal of the Korea institute for structural maintenance and inspection
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• v.28 no.4
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• pp.1-12
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• 2024

In this study, a determination method of structural member section based on Nonlinear behaviors of steel cable-stayed bridges and the Harmony Search algorithm was presented. The Harmony Search algorithm determines the structural member section of cable-stayed bridges by repeating the process of setting the initial value, initializing the harmony memory, configuring the new harmony memory, and updating the harmony memory to search for the optimal value. The nonlinear initial shape analysis of a three-dimensional steel cable-stayed bridge was performed with the cross-section of the main member selected by the Harmony Search algorithm, and the optimal cross-section of the main members of the cable-stayed bridge, such as pylons, girders, cross-beams, and cables, reflecting the complex behavior characteristics and the nonlinearity of each member was determined in consideration of the initial tension and shape. The total weight was used as the objective function for determining the cross-section of the main member of the cable-stayed bridges, and the load resistance ability and serviceability based on the ultimate state design method were used as the restraint conditions. The width and height ratio of the girder and cross-section were considered additional restraint conditions. The optimal sections of the main members were made possible to be determined by considering the geometry and material nonlinearity of the pylons, girders, and cross-sections and the nonlinearity of the cable members. As a result of determining the optimal cross-section, it was confirmed that the proposed analysis method can determine the optimal cross-section according to the various constraint conditions of the cable-stayed bridge, and the structural member section of the cable-stayed bridge considering the nonlinearity can be determined through the Harmony Search algorithm.

• 한국벤처창업학회:학술대회논문집
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• 2018.11a
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• pp.77-81
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• 2018

자본시장법 개정과 벤처 창업 활성화를 위해 크라우드펀딩(Crowdfunding)의 역할이 매우 중요해지고 있다. 크라우드펀딩은 자금 수요자가 자신의 사업이나 자금조달 목적을 홍보하여 불특정 대중(crowd)으로부터 자금공급 여부에 대한 집단지성(collectiveintelligence)을 이끌어내고, 온라인상의 전문중개기관(intermediation)을 통해 소액의 자금을 조달(funding)하는 행위이다(김세련, 2017). 본 연구는 2017년 4월부터 약 1년간의 질적연구로 주식 및 채권 발행을 통한 증권형 크라우드펀딩을 준비하여 성공한 기업 5곳의 면담 자료와 실제 현장에서 강사로 교육을 하면서 관찰한 참여관찰일지를 전사 및 코딩하였다. 이를 기반으로 첫째, 크라우드펀딩에 성공한 기업들의 특징을 밝혀내고 둘째, 크라우드펀딩에 관한 사전교육이 성공에 영향을 미치는지 확인하였다. 본 연구결과를 바탕으로 궁극적으로는 크라우드펀딩을 통해 성공적으로 자금 유치를 하기 위한 교육법을 밝혀내고자 하였다. 기존 교육방식에 자코토 교육철학을 접목시켜 자코토 교육법이 크라우드펀딩을 통한 자금유치 성공에 긍정적인 영향을 준다는 것을 밝혀낸다. 자코토의 교육법은 어떤 '설명'도 하지 않고 프랑스어를 완벽하게 배우도록 한 자코토의 실험이 누구나 알려는 의지를 갖는다면 새로운 것을 배울 수 있다는 지능의 동일성에 근거하여 학생들에게 알려는 의지를 불러일으키고 빠져나갈 수 없는 고리를 강제하여 스스로 앎을 얻도록 한 것을 말한다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.10
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• pp.1348-1354
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• 2020

The purpose of this study is to discover the occupational identity by examining the narrative of the life of a TVET teacher using the project method in programming fields. Teacher S, a participant in the study, started as a part-time lecturer at university and has been teaching programs for the past 20 years. As a result, six kinds of occupational identities of a programming teacher who teach by project method were found. S experienced pride and pride as a teacher through the project method. The project method served as a motive for continuous self-development to lead S to an expert. His experience as a positive teacher made him wish to maintain this life and live as a teacher as long as his health permits, even after retirement. This study has significance in exploring the structure of the occupational identity of a TVET teacher using the project method in programming fields, which have not been studied yet.

• Journal of Korean Society of Steel Construction
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• v.24 no.6
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• pp.683-692
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• 2012

The girders of cable stayed bridge are subjected to not only the bending moments but also additional compressive axial forces due to the horizontal components of cable forces. Because of these axial forces, the stiffness of girder can be decreased, and this problem should be considered especially for under-construction model rather than the full model. Korean domestic design specification suggests the linear elastic eigen value analysis for the stability problem of cable stayed bridges. However, this method cannot be applied to the under construction model because various geometric nonlinear characteristics cannot be considered. Therefore, in this study, 3 models which are assumed to be constructed by balanced cantilever will be considered experimentally and analytically to analyze the behavior of steel cable stayed bridges.

• Journal of the Korean Geosynthetics Society
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• v.16 no.4
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• pp.1-11
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• 2017

In this study, 1/6 small-scale model tests of helical piles were conducted to evaluate their installation time and ultimate capacities. Model sand layers were constructed using sand pluviating method to produce uniform soil relative density. For installation of different helical piles varying locations (vertical center-to-center spacings of 50 mm and 150 mm) of helix plates, two different rotation speeds of 15 rpm and 30 rpm were implemented. Cone penetration equipment was installed within the hallow section of the helical pile to increase ultimate capacity of helical pile and to evaluate soil properties of plugged soils and soils below pile tip after installation of the piles. Based on the test results, the most fasted installation was possible under the condition of "rotation speed of 30 rpm and center-to-center spacing of 50 mm", and the highest ultimate capacity was mobilized under the condition of "rotation speed of 30 rpm and center-to-center spacing of 150 mm with cone penetration implementation."