• Structural Engineering and Mechanics
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• v.20 no.1
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• pp.1-20
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• 2005

The present paper deals with the seismic response analysis and the evaluation of most likely failure modes for a water storage structure. For the stress analysis, a 3-D mathematical model has been adopted to represent the structure appropriately. The structure has been analyzed for both static and seismic loads. Seismic analysis has been carried out considering the hydrodynamic effects of the contained water. Based on the stress analyses results, the most likely failure modes viz. tensile cracking and compressive crushing of concrete for the various structural elements; caused by the seismic event have been investigated. Further an attempt has also been made to quantify the initial leakage rate and average emptying time for the structure during seismic event after evaluating the various crack parameters viz. crack-width and crack-spacing at the locations of interest. The results are presented with reference to peak ground acceleration (PGA) of the seismic event. It has been observed that, an increase in PGA would result in significant increase in stresses and crack width in the various structural members. Significant increase in initial leakage rate and decrease in average emptying time for the structure has also been observed with the increase in PGA.

• Journal of Plant Biotechnology
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• v.47 no.4
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• pp.309-315
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• 2020

Advances in biotechnology have led to progress in crop genetic engineering to improve agricultural productivity. The use of genetically modified (GM) crops has increased, as have consumers' and regulators' concerns about the safety of GM crops to human health, and ecological biodiversity. As such, the identification of GM crops is a critical issue for developers and distributors, and their labeling is mandatory. Multiplex polymerase chain reaction (PCR) has been developed and its use validated for the detection and identification of GM crops in quarantine. Herein, we established a simultaneous detection method to identify four GM maize events. Event-specific primers were designed between the junction region of transgene and genome of four GM maize lines, namely 5307, DAS-40278-9, MON87460, and MON87427. To verify the efficiency and accuracy of the multiplex PCR we used specificity analysis, limit of detection evaluation, and mixed certified reference materials identification. The multiplex PCR method was applied to analyze 29 living, modified maize volunteers collected in South Korea in 2018 and 2019. We performed multiplex PCR analysis to identify events and confirmed the result by simplex PCR using each event-specific primer. As a result, rather than detecting each event individually, the simultaneous detection PCR method enabled the rapid analysis of 29 GM maize volunteers. Thus, the novel multiplex PCR method is applicable for living modified organism volunteer identification.

• Journal of Distribution Science
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• v.13 no.9
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• pp.29-36
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• 2015

Purpose - The purpose of this study is to examine the influence of effective role-play and training on employee education satisfaction and customer orientation. Evidence of the suggested objective is obtained by monitoring the effectiveness of hotel service training. Research design, data, and methodology - Data were collected from 280 role-play sessions performed in a Korean Hotel and examined using a frequency analysis, reliability/validity assessments, correlation analysis, and regression analysis using SPSS 19.0. Results - 1) Entrepreneurs and training instructors should enthusiastically apply service education in order to enhance each employee d evaluation in terms of customer satisfaction and customer orientation. 2) The most effective factor on customer satisfaction and orientation is the instructor's qualifications. 3) Since a higher level of education-training satisfaction leads to better customer orientation, effective education-training is essential to achieve this result. Conclusions - The study was able to obtain practical evidence that can confirm that service education-training through role-play positively affects employee customer service orientation. In future advanced research on training effects on customer orientation, various internal factors of a business should also be considered.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.3
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• pp.357-362
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• 2011

Air springs are prevalently used as suspension in train. However, air springs are seldom used in automobiles where they improve stability and comfort by enhancing the impact-relief, breaking, and cornering performance. Thus, this study proposed a new method to analyze air springs and obtained some reliable design parameter which can be utilized in vehicle suspension system in contrast to conventional method. Among air spring types of suspension, this study focused on sleeve type of air spring as an analysis model since it has potential for ameliorating the quality of automobiles, specifically in its stability and comfort improvement by decreasing the shock through rubber sleeve. As a methodology, this study used MARC, as a nonlinear finite element analysis program, in order to find out maximum stress and maximum strain depending on reinforcement cord's angle variation in sleeves. The properties were found through uniaxial tension and pure shear test, and they were developed using Ogden Foam which is an input program of MARC. As a result, the internal maximum stresses and deformation according to the changes of cord angle are obtained. Also, the results showed that the Young's modulus becomes smaller, then maximum stresses decrease. It is believed that these studies can be contributed in automobile suspension system.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.47-48
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• 2019

Currently, the government has made a lot of efforts to improve construction productivity but there are few studies which measure between safety perception level and productivity in the South Korean construction industry. Therefore, the objective of this study is to analyze correlation between safety perception level of domestic construction companies and construction productivity. To achieve the objective, first, the concept of safety perception level was defined. Second, the safety perception level and construction productivity were investigated in the case projects. Third, correlation analysis was conducted between safety perception level and productivity. As a result, it was concluded that a high level of safety perception of executive and manager would increase construction productivity. In addition, To improve the safety perception level in the construction company, it is suggested that the provision safety resources for managements and the equal communication system between workers and managements and the development safety education tools considering the worker's experience. In the future, these findings can be utilized to develop future evaluation tools for a safety perception level in domestic construction company.

• Journal of Environmental Science International
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• v.29 no.5
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• pp.541-549
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• 2020

In this study, standard precipitation index- based analysis associated with run theory was performed using 53 years' (1967-2019) precipitation data to investigate the meteorological drought in Chuncheon. The duration of the meteorological drought in Chuncheon was 8.06 months, magnitude of the drought was -8.21, and average drought depth was -1.08. The drought in May 2014 lasted 21 months until January 2016; the drought scale and average depth was -34.06 and -1.62, respectively. This was the most severe drought in Chuncheon. As a result of drought frequency analysis, the drought scale of May to December in 2014 was estimated to be -16.16, and the return period was estimated to be 300 years. These results are expected to further increase the magnitude and frequency of weather droughts caused by climate change. Therefore, it is critical to prepare appropriate structural measures.

• Nuclear Engineering and Technology
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• v.51 no.5
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• pp.1297-1306
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• 2019

Probabilistic safety assessments (PSA) have been used for several decades to visualize the risk level of commercial nuclear power plants (NPPs). Since the role of a human reliability analysis (HRA) is to provide human error probabilities for safety critical tasks to support PSA, PSA quality is strongly affected by HRA quality. Therefore, it is important to understand the underlying limitations or problems of HRA techniques. For this reason, this study conducted a survey among 14 subject matter experts who represent the HRA community of domestic Korean NPPs. As a result, five significant HRA issues were identified: (1) providing a technical basis for the K-HRA (Korean HRA) method, and developing dedicated HRA methods applicable to (2) diverse external events to support Level 1 PSA, (3) digital environments, (4) mobile equipment, and (5) severe accident management guideline tasks to support Level 2 PSA. In addition, an HRA method to support multi-unit PSA was emphasized because it plays an important role in the evaluation of site risk, which is one of the hottest current issues. It is believed that creating such a catalog of prioritized issues will be a good indication of research direction to improve HRA and therefore PSA quality.

• Nuclear Engineering and Technology
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• v.54 no.3
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• pp.948-958
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• 2022

Since reliability and security of man-machine system increasingly depend on reliability of human, human reliability analysis (HRA) has attracted a lot of attention in many fields especially in nuclear engineering. Dependence assessment among human tasks is a important part in HRA which contributes to an appropriate evaluation result. Most of methods in HRA are based on experts' opinions which are subjective and uncertain. Also, the dependence influencing factors are usually considered to be constant, which is unrealistic. In this paper, a new model based on Dempster-Shafer evidence theory (DSET) and fuzzy number is proposed to handle the dependence between two tasks in HRA under uncertain and dynamic situations. First, the dependence influencing factors are identified and the judgments on the factors are represented as basic belief assignments (BBAs). Second, the BBAs of the factors that varying with time are reconstructed based on the correction BBA derived from time value. Then, BBAs of all factors are combined to gain the fused BBA. Finally, conditional human error probability (CHEP) is derived based on the fused BBA. The proposed method can deal with uncertainties in the judgments and dynamics of the dependence influencing factors. A case study is illustrated to show the effectiveness and the flexibility of the proposed method.

• Journal of The Korean Association For Science Education
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• v.13 no.1
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• pp.56-65
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• 1993

The purpose of this study is to analyze the inquiry activities of SCIIS and Korea primary school science curricular meterials and to make suggestions for the improvement of inquiry learning based on the analysis The Scientific Inquiry Evaluation Inventory (SIEI: Myung Hur, 1984) was used to evaluate the inquiry activity content of the primary school "Science, Level-6" and "SCIIS, Level-6" textbooks. The results are as follows: 1) The inquiry activities of Korean science textbooks are stressing on gathering and organizing data, but rarely require students to formulate a hypothesis, to design an experiment. 2) The SCIIS textbooks relatively tended to put more weight on interpreting/ analysing data and hypothesizing/ designing experiments. 3)The Korean science textbooks had little concern about establishing hypothesis and designing experiments, interpreting / analysing data. 4) The SCIIS textbooks require students to perform a variety of inquiry skills when compare to Korean science textbooks. 5) Competition / Cooperation Scale checks the level of competition and cooperation among student teams inherent in science curricular materials. The result from each team is incorporated into the formation of a class result. The communication is required to formulate a synthesized class response, enhances cooperation among teams. The SCIIS(84%) is the higher than Korea(50%) in cooperation scale. 6) Korean science textbooks rarely require students to discuss about experiment when compare to SCIIS textbooks. 7) Korean science textbooks provide students with both inquiry problems and experimental procedure, or including answers SCIIS textbooks provide students with both inquiry problems and experimental procedure, or problems only. 8) The Korean textbooks emphasize demonstrating or verifying of the text while the SCIlS emphasize extending the content of the text in inquiry scope scsle. The inquiry pyramid which helps analysis the inquiry activity curriculum as a whole is one of type 1- the course is centered on gathering and organizing data. The SCIIS are better than the Korean science textbook in the light of proportion of interpreting / analysing data and hypothesizing / designing experiments.

• Journal of the Korean Society of Radiology
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• v.12 no.2
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• pp.193-199
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• 2018

In this research, 15 patients were diagnosed with 1.5T and 3.0T MRI instruments (Philips, Medical System, Achieva) to minize Ferromagnetic artifact and find the optimized Tesla. Based on the theory that the 3.0T, when compared to 1.5T, show relatively high signal-to-ratio(SNR), Scan time can be shortened or adjust the image resolution. However, when using the 3.0T MRI instruments, various artifact due to the magnetic field difference can degrade the diagnostic information. For the analysis condition, area of interest is set at the background of the T1, T2 sagittal image followed by evaluation of L3, L4, L5 SNR, length of 3 parts with Ferromagnetic artifact, and Histogram. The validity evaluation was performed by using the independent t test. As a result, for the SNR evaluation, mere difference in value was observed for L3 between 1.5T and 3.0T, while big differences were observed for both L4, and L5(p<0.05). Shorter length was observed for the 1.5T when observing 3 parts with Ferromagnetic artifact, thus we can conclude that 3.0T can provide more information on about peripheral tissue diagnostic information(p<0.05). Finally, 1.5T showed higher counts values for the Histogram evaluation(p<0.05). As a result, when we have compared the 1.5T and 3.0T with SNR, length of Ferromagnetic artifact, Histogram, we believe that using a Low Tesla for Spine MRI test can achieve the optimal image information for patients with disk operation like PLIF, etc. in the past.