• Magazine of the Korea Concrete Institute
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• v.10 no.6
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• pp.241-252
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• 1998

The objective of the research stated herein is to observe the actual responses of a low-rise nonseismic moment-resisting reinforced concrete frame subjected to varied levels of earthquake ground motions. First, the reduction scale for the model was determined as 1 : 5 considering the capacity of the shaking table to be used and the model was manufactured according to the similitude law. This model was, then, subjected to the shaking table motions simulating Taft N21E component earthquake ground motions, whose peak ground accelations (PGAs) were modified to 0.12g, 0.2g, 0.3g, and 0.4g. The lateral accelerations and displacements at each story and local deformations at the critical reginos of the structure were measured. The base shear was measured by using self-made load cells. Before and after each earthquake simulation test, free vibration tests were performed to find the change in the natural period and damping ratio of the model. The test data on the global and local behaviors are interpreted. The model showed the linear elastic behavior under the Taft N21E motion with the PGA if 0.12g, which represents the design earthquake in Korea. The maximum base shear was 1.8tf, approximately 4.7 times the design base shear. The model revealed fairly good resistance to the higher level of earthquake simulation tests. The main components of its resistance to the high level of earthquakes appeared to be 1) the high overstrength, 2) the elongation of the fundamental period, and 3) the minor energy dissipation by inelastic deformations. The drifts of the model under these tests were approximately within the allowable limit.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.139-144
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• 2001

The objective of this study is to investigate the behavior of 1/12 scale upper-wall lower-frame reinforced concrete structure subjected to earthquake excitations. For this purpose, Taft N21E earthquake accelerogram was simulated by using 4m$\times$4m shaking table. When the input acceleration is compared to that of output, it was found that simulation of shaking table is satisfactory. From the test results with peak ground acceleration(PGA) 0.22g, which corresponds to 0.11g in prototype by the similitude law, it can be observed that the model responded in elastic behavior and that large interstory drift occurred at the lower part of the structure.

• Journal of the Korean Geosynthetics Society
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• v.16 no.1
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• pp.41-52
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• 2017

This research conducted the two types of model tests to examine the failure parameters by levee overflow, those were the pilot-scale levee (model height 0.4~0.8 m) and real scale levee (model height 1.0 m). The procedure of levee failure by overflow was succeeded to the following three steps: At first step, the local scouring on levee slope was happened and the overflow velocity was increased slowly. At second step, the enlarged scouring surface and the rapid overflow velocity were succeeded. At last, the levee section was broken totally and the overflow velocity was decreased because of the wide failure surface of levee. The levee failure angle (${\theta}$) was appeared bigger than slope failure angle of Rankine earth pressure. The enlarged levee height (H) made the faster overflow velocity (${\upsilon}$) of the levees, therefore additional tractive force was applied to it, futhermore the failure angle (${\theta}$) and failure surface (A) were enlarged. Because the sand sample for pilot-scale and real scale tests had the same diameter, the critical scouring velocity of each type was also the same, and the scouring properties were governed by variation of overflow velocity.

• Korean Journal of Culture and Social Issue
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• v.24 no.3
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• pp.385-410
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• 2018

Materialistic values can be a important variable to understand Koreans' psychological well-being and mental health. This study aimed to validate the Korean version of the Material Values Scale (K-MVS)(Richins & Dawson, 1992). In study 1, we performed confirmatory factor analysis(CFA) to ascertain the three factor model of the original MVS using 417 Korean undergraduate student data(sample 1). The CFA confirmed the three-factor model of the MVS. Yet, three items that yielded low factor loadings in this study as well as in other MVS validation studies were excluded from the final model. In study 2, content, construct, and concurrent validity of the K-MVS were examined with 650 undergraduate student data(Sample 2). We also tested measurement invariance across two groups(i.e., college student group of Sample 2 and employee group of Sample 3). The result revealed that the three-factor model of the K-MVS hold true across the two groups. Lastly test-retest reliability was calculated with 408 female college student data(Sample 4) that filled out K-MVS twice within 6 months. These findings suggest that the K-MVS is a reliable and valid measure for assessing materialistic values in Korea.

• Journal of Korea Entertainment Industry Association
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• v.14 no.1
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• pp.137-147
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• 2020

This study is aimed to develop and validate the clinical competence scale of occupational therapy student. The development of clinical competence scale analyzed the definition of clinical performance and previous studies. preliminary examinations were conducted on 203 occupational therapy departments in 3rd and 4th grade to verify item analysis and job validity. After exploratory factor analysis, eight factors of professional consciousness, 11 items of occupational therapy evaluation factors, 4 items of occupational therapy intervention factors, and 4 items of communication factors were extracted into a total of 27 factors. As a result of verifying the reliability of each factor through the internal consistency coefficient Cronbach's α, it was found to be .87~.94 and the overall reliability was .96. The correlation between the total score and the factors of the clinical competence scale was statistically significant. Through the confirmatory factor analysis, the model fit test of the factor structure for 27 items of 4 factors (χ²=.76, df = .31, CFI = .81, TLI = .80, RMSEA = .79) is considered acceptable. Through this study, The clinical competence scale is a valid and reliable scale that can be useful for objectively assessing.

• Journal of Space Technology and Applications
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• v.1 no.3
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• pp.319-336
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• 2021

This paper discusses the results of launch environment tests for the engineering qualification model (EQM) of nanosatellite Scale magNetospheric and Ionospheric Plasma Experiment (SNIPE) for scientific missions and lessons learned for the design of nanosatellites. SNIPE is a group of four formation-flying 6U nanosatellites with a range of payloads for missions including space weather measurement. We developed the EQM to verify the preliminary design prior to fabricating the flight model. Launch environment test of EQM was conducted for the first time in 2019, and all failures were corrected and verified at the second test conducted in 2021. A notable point of the two tests is that the nanosatellite deployer used in the first test is different from that of the second test. The second deployer has the capability to fix the internal satellite whereas the first deployer just contains and deploys the satellite. Thus actual mechanical loads the satellite receives is reduced for the second test compared to the first test. This work compares the mechanical responses of two tests and proposes general guidelines for structural design of nanosatellites.

• Journal of the korean Society of Automotive Engineers
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• v.14 no.1
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• pp.13-24
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• 1992

1) 1/2 Scale Model 실험과 실제품 성형실험을 통하여 정밀 냉간단조에 의한 Tripod Slide Housing의 제조공정 설계기술을 확립하고, 4단계 성형공정으로 시제품 제작에 성공하였다. 2) Triod Slide Housing을 성형할 수 있는 4단계(전방압출, Heading, 후방압출, Ironing)의 금형을 설계 및 제작하여 시제품 생산에 적용하고, 관련 필요기술을 축적하였다. 3)XC 48 등 중,고탄소강의 소둔 실험을 통하여 소둔 조건에 따른 구상화율 및 경도의 변화에 대한 연구를 수행함으로써, 고탄소강의 냉간단조시에 필요한 최적 소둔 조건에 응용할 수 있는 자료를 축적하였다.

• Journal of Korea Port Economic Association
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• v.32 no.2
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• pp.123-135
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• 2016

This study uses Data Envelopment Analysis(DEA) to investigate the management efficiency of Korean shipping companies based on business administration costs such as corporate entertainment, advertisement, and labor costs. We analyze shipping enterprises listed on the Korean stock market of the period of 2010-2014. Corporate entertainment, advertisement and labor costs are used as input variables and sales and net income are used as output variables. We use technical efficiency, pure technical efficiency, scale efficiency and returns to scale to propose a plan to improve the efficiency of inefficiency decision-making units (DMUs). The results of the efficiency analysis show that six of the DMUs in the technical efficiency of CCR model and eight of the DMUs in the pure technical efficiency of BCC model are in efficient state. In terms of return to scale, six of the DMUs(24% of all DMUs) show increasing returns to scale, while 13 DMUs(52% of all DMUs) showdecreasing returns to scale. Because multiple efficient state for DMUs exist in the technical efficiency analysis, we conduct a super efficiency analysis. The results show that the efficient state of the twomost efficient DMUs are 1.314 and 1.243, respectively. This implies that these DMUs could maintain their current levels of the efficiency if they increase the amount spent on advertisements, corporate entertainment and labor costs by 31.4% and 24.3%. respectively. We conclude this study by providing the efficiency states of each DMU and target for improving the inefficiencies in each case.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.08a
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• pp.277-284
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• 2004

Low carbon steels containing Si of up to $1.2\;wt\%$ were oxidized in air at 1373 K and 1523 K, i.e. below and above the eutectic temperature of FeO and $Fe_2SiO_4$. The influence of a impurity element, S on behavior of scale formation during oxidation was investigated by using $M\"{o}chssbauer$ spectroscopy and EDS. This allowed establishment of an interface oxidation model of Si-added steel depending on temperature and an impurity element. A compound of FeO and FeS was formed in the scale/matrix interface of low carbon steels containing S of up to $0.03\;wt\%$ oxidized above 1213 K of the eutectic temperature. This was flat formed between $Fe_2SiO_4$ nodules along the scale/matrix interface without selective oxidation. It is due to low viscosity and high wettability of the compound of FeO and FeS in liquid. Conventional metallographic examinations revealed that roughness of the scale/matrix interface in Si-added steels became flat as the content of S increased. It was independent of oxidizing temperature and Si content. Effects of oxidizing temperature and an impurity element content on descaling characteristics in Si-added steels were evaluated by using a hydraulic descaling simulator. Good descaling characteristics was attributable to this flatness of the scale/matrix interface.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.4
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• pp.2229-2233
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• 2016

Background: Breast cancer is one of the most common cancers among women in the world. Early detection is necessary to improve outcomes and decrease related costs. The aim of this study was to assess the predictive power of health locus of control as a modifying factor in the Health Belief Model (HBM) for prediction of breast self-examination. Materials and Methods: In this cross- sectional study, 400 women selected through the convenience sampling from health centers. Data were collected using part of the Champion's HBM scale (CHBMS), the Health Locus of Control Scale and a self administered questionnaire. For data analysis by SPSS the independent T test, Chi square test, logistic and linear regression modes were appliedl. Results: The results showed that 10.9% of the participants reported performing BSE regularly. Health locus of control did not act as a predictor of BSE as a modifying factor. In this study, perceived self-efficacy was the strongest predictor of BSE performance (Exp (B) =1.863) with direct effect, while awareness had direct and indirect influence. Conclusions: For increasing BSE, improvement of self-efficacy especially in young women and increasing knowledge about cancer is necessary.