• Journal of the Computational Structural Engineering Institute of Korea
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• v.23 no.3
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• pp.289-301
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• 2010

A structural model of the SNF(spent nuclear fuel) disposal canister for the PWR(pressurized water reactor) for about 10,000 years long term deposition at a 500m deep granitic bedrock repository has been developed through various structural safety evaluations. The SNF disposal baskets of this canister model have the array type of which four square cross section baskets stand parallel to each other and symmetrically with respect to the center of the canister section. However whether this developed structural model of the SNF disposal canister is best is not determinable yet, because the SNF disposal canister with this parallel array has a limitation in shortening the diameter for the weight reduction due to the shortest distance between the outer corner of the square section and the outer shell. Therefore, the structural safety evaluation of the SNF disposal canister with the rotated basket array which is also symmetric with respect to the canister center planes is very necessary. Even though such a canister model has not been found as yet in the literature, the structural analysis of the canister with the rotated basket array for the PWR is required for the comparative study of the structural safety of canister models. Hence, the structural analysis of the canister with the rotated basket array in which each basket is rotated with a certain amount of degrees around the center of the basket itself and arrayed symmetrically with respect to the center planes is carried out in this paper. The structural analysis result shows that the SNF disposal canister with the rotated basket array in which the SNF disposal basket is rotated as 30~35 degrees around the center of the basket itself is structurally more stable than the previously developed SNF disposal canister with the parallel basket array.

• Structural Engineering and Mechanics
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• v.73 no.2
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• pp.167-179
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• 2020

This study provides a simplified method for the evaluation of shear lag stress in rectangular box T-joints. The occurrence of shear lag phenomenon in the box T-joint generates stress concentration localized at both web-flange junctions of the beam, which leads to cracking or failure in the weld region of the joint. To prevent such critical circumstance, peak stress at the weld region is required to be checked during a preliminary design stage. In this paper, the shear lag stresses in the T-joints were evaluated using least-work solution in which the longitudinal displacements of the beam flange and web were presumed. The evaluation process considered particularly the effect of column flange flexibility, which was represented by an axial spring model, on the shear lag stress distribution. A simplified method for stress evaluation was provided to avoid solving complex mathematical problems using a stress modification factor β_s from a parametric study. The results showed that the proposed method was valid for predicting the shear lag stress in the box T-joints manually, as well compared with finite element results. The results are further summarized, discussed, and clarified that more flexible column flange caused higher stress concentration.

• Journal of Korean Society of Rural Planning
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• v.16 no.3
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• pp.159-171
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• 2010

Since rapid industrialization of Korean society, out-of-village roads have been greatly improved, while almost all of in-village roads have not been fundamentally improved yet. Unless village roads should be improved in relatively comparison with trunk roads, it has been widely recognized that grass rooted achievement of accessibility revolution not be realized. In this regard, this study tried to develop evaluation indicators system for improvement of village roads. The evaluation indicator system on village road conditions was proposed which is sub-categorized as structural improvement of road itself, its communication serviceability and public securing level of property rights of road site. The system has 6 indicators(2 of each subcategory);good pavement ratio and over 3m wide road length ratio, ratio of household fronting under 2m wide road and connectivity of road network, ratio of registered as 'road' in land category and ratio of publicly owned road sites. In the final conclusion, village roads in rural Korea have been generally in worse condition regardless of whether prior improvement works or not, except some of recent plan-based improvement villages.

• Journal of Distribution Science
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• v.17 no.11
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• pp.5-15
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• 2019

Purpose: This study aimed to empirically demonstrate how self-esteem, self-efficacy, locus of control, and neuroticism, which is core self-evaluation factors of door-to-door salespersons within food and cosmetic retail industry, affected the sales performance of female salespersons via job satisfaction and organizational commitment. Research design, data and methodology: Using a 23-item questionnaire constructed based on previous studies, this study selected six domestic door-to-door sales companies and conducted a 1:1 face-to-face survey with female door-to-door salespersons belonging to branches and agencies in Seoul and the capital region. The data of 208 respondents were analyzed. The results of path analysis based on structural equation modeling and mediation analysis through the Sobel test were presented. Results: Self-efficacy and locus of control had the largest effect on job satisfaction and organizational commitment, respectively. Neuroticism, however, did not significantly influence job satisfaction and organizational commitment. Overall, core self-evaluation factors positively affected sales performance via job satisfaction but not via organizational commitment. Conclusions: This study found that factors which were oriented to female salespersons' ability and sales goals, such as self-efficacy and job satisfaction, were considered important in managing them in the door-to-door sales-distribution channels. In the future, policies should be developed for managing female door-to-door salespersons to help them achieve job satisfaction.

• Journal of the Society of Naval Architects of Korea
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• v.43 no.4 s.148
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• pp.467-475
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• 2006

Fatigue strength of hull structural steel plate, extracted from longitudinal bulkhead of a 17-year-old ore/oil carrier for renewal, was investigated in air and in artificial seawater condition. The surface of the plate was covered with corrosion pits and they proved to be crack initiation sites by fractography using SEM. From this research, it was found that the evaluation method for fatigue strength of virgin mild steel plates in air and in artificial seawater can also be applied to the evaluation of the fatigue strength of mild steel plates those were long-term exposed to a corrosive environment and their surfaces had been rusted intensively.

• Special Issue of the Society of Naval Architects of Korea
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• 2017.10a
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• pp.93-104
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• 2017

IMO type C independent tank is one of the cargo containment system specified on IGC code. It is normally adopted for small and medium size liquefied gas carrier's cargo containment system and it can be applied to fuel tank of LNG fueled vessel. This study focuses on rule scantling process and evaluation methods in early design stage of type C independent tank. Actual design results of 22K LPG/Ammonia/VCM carrier's No.2 cargo tank are demonstrated. This paper presents the calculation methods of design acceleration and liquid height for internal design pressure as defined on IGC code. And this paper shows the applied results of classification rules about shell thickness requirement and buckling strength. Additionally this paper deals with evaluation methods of structural strength and cumulative fatigue damage using FE analysis.

• Journal of Industrial Technology
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• v.38 no.1
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• pp.21-27
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• 2018

In January 2018, the Ministry of Education published "Seismic design criteria for school buildings" and "Manual for seismic performance evaluation and retrofit of school buildings" to evaluate seismic performances through linear analysis. This paper evaluates the seismic performance of an old school building through the linear analysis. The target building was constructed in the late 1970s, and the seismic-force-resisting system was assumed to be a reinforced concrete moment frame with an un-reinforced masonry wall. As a result of the evaluation, the target building does not satisfy the 'life safety' level of 1.2 times the design spectrum. The average strength ratio of moment frames, an indicator of the level of seismic performance tends to be controlled by beams. However, through the Pohang earthquake, it was known that the short column effect caused by the partially infilled masonry wall caused shear failure of the columns in school buildings. Therefore, it is necessary to improve the linear analysis so that the column controls the average strength ratio of moment frames.

• Computers and Concrete
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• v.19 no.3
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• pp.283-291
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• 2017

A large number of residential buildings in regions subjected to severe earthquakes do not have enough load carrying capacity. The most of them have been constructed without receiving any structural engineering attention. It is practically almost impossible to perform detailed experimental evaluation and analytical analysis for each building to determine their seismic vulnerability, because of time and cost constraints. This fact points to a need for a simple evaluation method that focuses on selection of buildings which do not have the life safety performance level by adopting the main requirements given in the seismic codes. This paper deals with seismic assessment of existing reinforced concrete residential buildings and contains an alternative simplified procedure for seismic evaluation of buildings. Accuracy of the proposed procedure is examined by taking into account existing 250 buildings. When the results of the proposed procedure are compared with those of the detailed analyses, it can be seen that the results are quite compatible. It is seen that the accuracy of the proposed procedure is about 80% according to the detailed analysis results of existing buildings. This accuracy percentage indicates that the proposed procedure in this paper can be easily applied to existing buildings to predict their seismic performance level as a first approach before implementing the detailed and complex analyses.

• Structural Engineering and Mechanics
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• v.30 no.5
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• pp.535-558
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• 2008

This study evaluates seismic performance of the school buildings with the selected template designs in Turkey considering nonlinear behavior of reinforced concrete components. Six school buildings with template designs were selected to represent major percentage of school buildings in medium-size cities located in high seismic region of Turkey. Selection of template designed buildings and material properties were based on field investigation on government owned school buildings in several cities in western part of Turkey. Capacity curves of investigated buildings were determined by pushover analyses conducted in two principal directions. The inelastic dynamic characteristics were represented by equivalent single-degree-of-freedom (SDOF) systems and their seismic displacement demands were calculated under selected ground motions. Seismic performance evaluation was carried out in accordance with recently published Turkish Earthquake Code that has similarities with FEMA-356 guidelines. Reasons of building damages in past earthquakes are examined using the results of performance assessment of investigated buildings. The effects of material quality on seismic performance of school buildings were investigated. The detailed examination of capacity curves and performance evaluation identified deficiencies and possible solutions for template designs.

• Journal of Korean Academy of Nursing
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• v.40 no.5
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• pp.631-641
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• 2010

Purpose: This study was done to develop standards for dementia care as a baseline for professional nurses to provide a framework for dementia care evaluation Methods: The dementia care standards were developed through a literature review and focus group discussions. According to the Delphi method, the data analysis was conducted using the Content Validity Index (CVI). Results: The final set of 18 standards on dementia care was developed through one round of CVI. The standards included four structural standards: 'Organization of nursing system', 'Operating system', 'Management of human resources', 'Management of material resources', 13 procedural standards: 'Advanced assessment', 'Nursing diagnosis', 'Nursing plam', 'Advanced nursing implementation', 'Evaluation', 'Education', 'Research', 'Consultation', 'Counseling and cooperation', 'Development of specialty', 'Utilizing resources', 'Nursing quality assurance', 'Ethics', and one standard concerning outcome ('Evaluation of nursing tasks in care of patients with dementia'). The final set of 55 criteria on care of patients with dementia was confirmed through two rounds of CVI. The final 171 indicators were confirmed through four rounds of CVI. Conclusion: These dementia care standards provides a framework that allows registered nurses to clarify their roles and tasks in the care of patients with dementia and provides evaluation criteria.