• Composites Research
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• v.26 no.4
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• pp.207-212
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• 2013

In this study, the thickness optimization for uni-directional (UD) glass fiber reinforced polymer (GFRP) laminates of the spar cap of composite tidal blades was performed under the tip deflection constrains. The spar cap was composed of GFRP composites and carbon fiber reinforced polymer (CFRP) composites. The stress distributions in the blade as well as its material costs for the optimized results were additionally investigated. The optimized thickness was obtained by interacting a sequential quadratic programming (SQP) algorithm and an ABAQUS software to calculate an objective function. It was confirmed that the thickness of UD GFRP increased with a decrease of the restrained tip deflection when a thickness of UD CFRP laminates was constrained to 9 mm. The weight of the optimized spar-cap increased up to 96.2% while the maximum longitudinal tensile stress decreased up to 24.6%. The thickness of UD GFRP laminates increased with a decrease of the thickness of UD CFRP laminates when the tip deflection was constrained to 126.83 mm. The weight increased up to 40.1%, but the material cost decreased up to 16.97%. Finally, the relationships among the weight, internal tensile stress, and material costs were presented based on the optimized thicknesses of the spar cap.

• The Journal of the Korea Contents Association
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• v.20 no.11
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• pp.228-236
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• 2020

As of March 2020, this study divided the applications for young children installed on Android-based smart-phones in Korea into top and bottom groups according to review scores, and selected 30 applications each, conducted content analysis and application evaluation, and looked at differences between groups. Through this, by providing objective information on the smart-phone application for young children, it is intended to help parents and early childhood education professionals select high-quality applications, and to present ideas and directions for developing applications suitable for development to application developers. As a result of application content analysis, only data presentation type, simulation type, and game type were found in all the top and bottom groups as for the application type. There was a difference in order. In the case of app purchase cost, the top group in the review score was evenly distributed from the low price to the high price of 100,000 won or more, while the bottom group had few high-priced applications. On the other hand, as a result of application evaluation, a significant difference was found in the entire evaluation score, including all functional elements and all content elements, between the top and bottom groups of the review score. In the case of detailed sub-factors, significant differences were shown in all factors except 'technicality' of functional elements.

• Journal of Digital Convergence
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• v.10 no.6
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• pp.133-140
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• 2012

This study starts from interests on an endeavor of each economy unit, especially the enterprises, for the survival and sustainability of themselves. Competition, how to get it, maintain it and advance it! Agreeing the perceivedness of industries, scholars and public; what the core competition of manufacturer is an competitiveness of product, this study focuses on the PLM system as the key solution for obtaining the competitiveness of product with reviewing the contents and studies of PLM formulated. PLM is highlighted as the one of top tier ICT solution for the product development domain of manufacturing industry today. First of all, this study deals with the opinion of actual work-site and management of our small&medium business for the benefits of PLM based on product development; the impact on the performances of management, which is the key objective of the existence of enterprises. In conclusion, the answers for these questionnaires shows positive perception of actual work-sites and managers for the PLM system. They agree some useful effects on shortening the term and downsizing the cost of product development due to Data integration and Process management, even if they have not full confidence on the effectiveness of the individual functionality of the PLM system.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.12
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• pp.1667-1673
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• 2012

The objective of this study was to estimate economic weights of Hanwoo carcass traits that can be used to build economic selection indexes for selection of seedstocks. Data from carcass measures for determining beef yield and quality grades were collected and provided by the Korean Institute for Animal Products Quality Evaluation (KAPE). Out of 1,556,971 records, 476,430 records collected from 13 abattoirs from 2008 to 2010 after deletion of outlying observations were used to estimate relative economic weights of bid price per kg carcass weight on cold carcass weight (CW), eye muscle area (EMA), backfat thickness (BF) and marbling score (MS) and the phenotypic relationships among component traits. Price of carcass tended to increase linearly as yield grades or quality grades, in marginal or in combination, increased. Partial regression coefficients for MS, EMA, BF, and for CW in original scales were +948.5 won/score, +27.3 $won/cm^2$, -95.2 won/mm and +7.3 won/kg when all three sex categories were taken into account. Among four grade determining traits, relative economic weight of MS was the greatest. Variations in partial regression coefficients by sex categories were great but the trends in relative weights for each carcass measures were similar. Relative economic weights of four traits in integer values when standardized measures were fit into covariance model were +4:+1:-1:+1 for MS:EMA:BF:CW. Further research is required to account for the cost of production per unit carcass weight or per unit production under different economic situations.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.4 no.1
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• pp.27-48
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• 1984

This study is conserned with the optimization of reinforced concrete frames using limit state design theory. Formulations of the optimal design for reinforced concrete frame based on the limit state theory turn out to be the nonlinear programming problems which have to deal with the required steel area, the width and effective height of the beam and column section and the moment reduction factor as the design variables. The objective function is formulated as the total construction cost which considers the costs of steel, concrete and forming for the reinforced concrete frames, and the basic constraints are imposed upon both ultimate and serviciability limit state concepts. Also, the stress blocks assumpted in CP110 and Hognestad et al. theory are applied to analysis an ultimate resistant section force for the ultimate limit state and only the criteria of CP110 are used for serviciability limit state. The optimized technique which is applied to solve the nonlinear programming problems for the optimization of reinforced concrete frames is SUMT utilizing the modified Newton-Raphson method. This algorithm is used to test for the two reinforced concrete frames, and then is compared and analysized with the numerical results of reference(10) to examine its convergence, applicability and stability under the same conditions. The results of this study are discussed about the economy comparision of the optimal values for CP110 and Hognestad et al., and the applicability, stability, convergence and validity of this algorithm used herein through the numerical analyses.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.32 no.5
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• pp.551-560
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• 2014

Compare to other industrial sites, the civil construction work not only takes longer time but also has made of complicated processes, such as the integrated management, process control, and quality control until the completion. However, it is hard to take control the construction sites, since numerous issues are always emerged. The study purposes on providing the dataset to synthetically manage and monitor the civil construction site, main design, drawings, process, construction cost, and others at real-time by using the low altitude close-range aerial images, based on UAV, and the GPS surveying method for treating the three-dimensional spatial information quickly and accurately. As a result, we could provide the latest information for the quick decision-making following from planning to completion of the construction, and objective site evaluation by the high-resolution three-dimensional spatial information and drawings. Also, the present map, longitudinal map, and cross sectional view are developed to provide various datasets rapidly, such as earthwork volume table, specifications, and transition of ground level.

• Therapeutic Science for Rehabilitation
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• v.7 no.4
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• pp.7-18
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• 2018

Objective: The purpose of this study was to investigate the effects of telerehabilitation on stroke patients through remotely operated intervention and monitoring. Methods: Literature from 2000 to April 2018 was collected through PubMed, Embase, Cochrane, and RISS. We used telerehabilitation, telemedicine, and stroke as the search terms in regard to foreign literature, and the terms telerehabilitation, stroke, and CVA in regard to Korean literature. A total of 406 foreign and 15 Korean published studies were found. As a result, a total of seven documents was selected for the analysis. Results: As a result of the analysis, all the interventions applied through telerehabilitation were provided remotely, and significant effects were reported between pre-post assessments. In addition, the significant effects of telerehabilitation were reported through analyzing pre-post(n=7) and between groups(n=4) assessments. The monitoring used could be categorized according to purpose, that is, for checking (n=3) and as an intervention (n=4). Conclusions: This study confirmed, within limits, that the application of telerehabilitation could be a potential alternative for stroke patients with limited rehabilitation services. In order to apply telerehabilitation in Korea, it is necessary to study the cost effectiveness, according to the current domestic situation, and confirm the most effective monitoring method based on the intervention.

• Journal of Distribution Research
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• v.11 no.1
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• pp.41-68
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• 2006

Today, Manufacturing companies execute the logistics outsourcing that commits the non-core logistic function to the specialized logistics corporation, which makes the manufacturing company focus on its core competence, product development and marketing, reduces logistics cost and improves customer service level. Recently, Logistics outsourcing is developed into cooperative sourcing based on the partnership. Case study on the logistics outsourcing will provide the good guideline for planning of the outsourcing strategy. The objective of this research is making a sense about 4PL through the case of UPS-Samsung Electro-Mechanics and catching major issue to provide the guideline for the cooperation outsourcing strategy. We investigated historical backgrounds of the logistics outsourcing between UPS and Samsung Electro-Mechanics. We also investigated problems occurred in outsourcing process at the five dimensions-organizational problem, CEO's short-term views, cultural gap between two companies, integration of IT system, and different understanding about outcomes. We expect to give many implications to manufacturing companies which want to cooperate with specialized logistics corporation.

• International Journal of Highway Engineering
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• v.12 no.1
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• pp.79-86
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• 2010

Cold in-place recycling (CIR) using emulsified asphalt or foamed asphalt has become a more common practice in rehabilitating the existing asphalt pavement due to its cost effectiveness and the conservation of paving materials. As CIR continues to evolve, the engineered emulsified asphalt was developed to improve the field performances such as coating, raveling, retained stability value and curing time. The main objective of this research is to compare the laboratory responses of the engineered emulsified asphalt (CIR-EE) mixtures against the foamed asphalt (CIR-foam) mixtures using the reclaimed asphalt pavement (RAP)materials collected from the CIR project on U.S. 20 Highway in Iowa. Based on the visual observation of laboratory specimens, the engineered emulsified asphalt coated the RAP materials better than the foamed asphalt because the foamed asphalt is to create a mastic mixture structure rather than coating RAP materials. Given the same compaction effort, CIR-EE specimens exhibited lesser density than CIR-foam specimens. Both Marshall stability and indirect tensile strength of CIR-EE specimens were about same as those of CIR-foam specimens. However, Marshall stability and indirect tensile strength of the vacuum-saturated wet specimens of CIR-EE mixtures were higher than those of CIR-foam mixtures. After four hours of curing in the room temperature, the CIR-EE specimens showed less raveling than the CIR-foam specimens. On the basis of test results, it can be concluded that the CIR-EE mixtures is less susceptible to moisture and more raveling resistant than CIR-foam mixtures.

• Korean Journal of Social Welfare
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• v.59 no.2
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• pp.65-88
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• 2007

This study evaluates psychometric properties of the Revised Memory and Behavioral Problems Checklist(RMBPC) in Korean version. The sample includes 387 South Korean family caregivers who provide the majority of day to day tasks and emotional care for their older family members with physical and/or cognitive disabilities. The psychometric properties of the RMBPC are verified by item analysis, exploratory factor analysis(EFA) & confirmatory factor analysis(CFA). For cross-validity, the randomly divided two samples are used: one sample for EFA(n=193, 387/2) and the other sample for CFA(n=194, 387/2). The internal consistency of the K-RMBPC is excellent, and the convergent and criterion-related validity of the K-RMBPC with related variables is empirically confirmed. An EFA based on the Principal Component Analysis(PCA) method with varimax rotation explains 65.85% of variance accounted for by the three factors. A CFA also verifies that the model fit was acceptable. The shorter Korean version of the RMBPC is found reliable and valid. The translated checklist would be very useful for clinical and research settings by (a) focusing on observable, conceptually relevant, potentially modifiable behaviors and (b) using objective criteria within a self-administered framework, to enable clinicians and researchers to pinpoint areas of disturbance and target intervention goals for patients and caregivers in a cost-effective manner.