• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.4
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• pp.307-312
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• 2017

Laser cladding has some advantages compared to conventional cladding technologies such as arc welding and thermal spraying. Laser cladding produces a metallurgically well-bonded clad layer with a lower dilution ratio and few defects. Based on the characteristics of a 1-pass clad layer with many parameters, which were investigated in a previous report, it was found that it was essential to overlap a 1-pass clad layer when cladding a large area. In this study, the shape differences of multi-pass clad layers with various overlapping ratios were compared. Then, the alloying element distribution of cladding with a certain overlapping ratio was investigated using EDS and EPMA. As the overlapping ratio increased, the length of the clad decreased and its height increased. In addition, the height of the multi-pass cladding was higher than that of the 1-pass cladding under the same condition. The Fe content of the highly diluted first clad was found to be approximately 20 % in an element analysis. However in the area outside of the first clad, the Fe content was decreased to 10 % as a result of minimum dilution, and a uniform distribution of elements was found.

• Journal of the Korean association of regional geographers
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• v.15 no.1
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• pp.115-137
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• 2009

Recently, industrial locations have faced changing trends under the influence of emerging industries as well as advanced new technologies. So the purpose of this study is to analyze the spatial distribution and locational factors of biotechnology industry formed around the Seoul Metropolitan area and Daejeon city, both of which are centers of Korean biotechnology industry, and is also to identifytheir locational characteristics. Major results of this study can be outlined as follows: First, from the mid 1990' s to 2000, Korean biotechnology industry has rapidly developed owing to central and local governmental support policies and systems as well as changes in domestic economic environment due to Korean financial crisis. Secondly, it was found that spatial distribution of Korean biotechnology industry converged on the Seoul Metropolitan area till 1990, but shifted from there to Daejeon and Chungcheong area from 1990 to 2000. Particularly after 2000, positive local governmental efforts to attract biotechnology players have driven the spatial distribution of biotechnology industry to shift from Seoul Metropolitan area and Daejeon or adjacent area gradually to other profitable locations. In terms of locational factors, it was found that the locations of Korean biotechnology industry converged primarily on university or college campus and biotechnology venture center, particularly on locations adjacent to superhighway or expressway. Locational factors varied depending on region, industrial type and business growth phase. Therefore, it is advisable that our central and local government should make and implement practical and useful policies in favor of biotechnology business depending on region, industrial type, business growth phase, rather than depending on uniform locational policies.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.8
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• pp.273-284
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• 2017

This study performed meta-analysis of published articles to examine the relationship between sarcopenia and smoking. We searched the PubMed, EMBASE, Cochrane library, and RISS database sup to January 2017 using search terms such as sarcopenia AND (smoking OR tobacco OR cigarette). A total of 25 articles were included in the analysis (seven cohort studies and 18 cross-sectional studies). Incidence of sarcopenia in smokers and non-smokers was analyzed by the random effects model. Incidence of sarcopenia was OR 1.49 (95% CI 1.21, 1.84, p<.001, I2 = 88.20%), Asian (OR 1.28, 95% CI 0.91, 1.78, p=0.150, I2=85.32%), and Western (OR 1.65, 95% CI 1.25, 2.17, p<.001, I2=91.08%), Western smokers showed a significantly higher incidence of sarcopenia:males and females with OR 1.25(95% CI 1.11, 1.40, p<.001, 12=87.4%) and 1.80(95% CI 0.98, 3.30, p=.057, 12=89.1 %) respectively. Male smokers showed significantly higher incidence of sarcopenia. Based on the results of the study, smoking in Western males is related to sarcopenia. However, since the criteria for the diagnosis of sarcopenia and the criteria for smoking were different, cumulative individual clinical studies applying uniform assessment for the evaluation of sarcopenia and smoking status are needed in the future.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.391-397
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• 2017

Recently, digital image correlation (DIC) techniques have been used to measure dynamic deformation during tensile testing. The standard tensile test method measures the average displacement of the relevant specimen to calculate the true stress-strain curve. Therefore, the validity of the true stress curve is restricted to the stress incurred within the uniform stretching interval, i.e., the maximum stress corresponds to the starting point of the necking deformation. Alternatively, if DIC is used, the effective range of the strain and strain rate can be extended to the breaking point of the tensile specimen, because of the feasibility of measuring the local strain over the entire area of interest. Because of these advantages, many optical 3D measurement systems have been introduced and used in research and industry. However, the conventional 3D measurement systems are exceedingly expensive and time consuming. In addition, these systems have the disadvantage of a very large equipment size which makes their transport difficult. In this study, a 2D image correction method employing a 2D DIC measurement method in conjunction with a numerical analysis method is developed using a smartphone. The results of the proposed modified 2D DIC method yielded higher accuracy than that obtained via the 3D measurement equipment. In conclusion, it was demonstrated that the proposed 2D DIC and calibration methods yield accurate measurement results with low time costs.

• Journal of Distribution Science
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• v.12 no.8
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• pp.83-90
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• 2014

Purpose - Increasing sales of PB rice products can hinder the growth of domestic brands of rice, notwithstanding that the government is promoting domestic brands of rice. This analysis evaluated the influencing relationship among the variables of PB image, product credibility, and purchase intention of consumers who have never bought PB rice, to know the factors influencing consumers' decisions to purchase PB products. Research design, data, and methodology - PB products' brand image was analyzed as the factor that has a direct effect on purchase intention. The mediation effect of credibility on PB products is also analyzed, in terms of influencing the relationship between PB products' brand image and purchase intention. The analysis is performed on consumers that have not purchased a PB product and consumers who have purchased PB products from major distributors. Data is collected through questionnaires, from 389 of responders, and the AMOS 19.0 statistics package is used as a statistical tool. Results - It is proven that brand image has direct effects on the credibility of the product, and the credibility of product has a direct effect on purchase intention. However, it is revealed that brand image does not directly affect purchase intention, but that brand image indirectly affects it through the credibility of the product. Although the customers' recognition about PB image is low, the result shows that PB products' external attributes have effects on customers' purchase intention relating to the PB product. Therefore, it is important to establish the credibility of the PB product more than other products in terms of marketing. Conclusions - The following are the implications of the study. First, in a rice brand promotion, the credibility of the product should be ensured by a uniform brand image. To ensure the credibility of a product, the RPC brand and other brands should be unified, and the unified brand image should be applied to every product. Second, the package must possess a design as well as contents that could build consumers' perception of product credibility. Products' external attributes contribute to their credibility, which leads the consumers to purchase the products, including those consumers who have never bought PB rice products. Therefore, the products' credibility and sales can be reinforced by applying information about consumers' considerations when buying the PB rice product in different colors, font sizes, and packaging designs. This study is meaningful in two ways. First, it seeks to identify an NB revitalization strategy by exploring the purchasing behavior of customers who have no experience in buying PB rice products. Second, the results of previous studies about general brands are considered and applied in this study in order to investigate the influencing relationship among different factors of PB products. However, this study is a consumer awareness investigation; therefore, its results only have limited meaning to the relationship between brand image and purchase intention.

• Polymer(Korea)
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• v.38 no.2
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• pp.193-198
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• 2014

Lens and DVD require high quality of optical property. Conventional injection molded products contain high residual stress and this invokes birefringence since high cavity pressure and high temperature variation are involved in a molding process. Thus these products are often molded by injection compression molding in order to minimize the residual stress through reducing cavity pressure and uniform cavity pressure. In this study, molding parameters affecting molding quality such as property uniformity in injection compression molding were investigated through experiment. Molding quality deviations among the cavities in multi-cavity mold were also studied. Transparent resins, PC and PS were used in this study. Compression gap, compression speed, compression force, and compression delay time for processing variables in injection compression molding were applied in experiment. Compression force, compression delay time, and compression gap significantly affected the optical property of product. The degree of influence of process variable on the product quality was different in different resins. This implies that the optimal operational conditions in injection compression molding existed for each resin according to flow property.

• Journal of Convergence for Information Technology
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• v.7 no.2
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• pp.43-51
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• 2017

Background/Objectives : The purpose of this study is to propose a multi-threaded web crawl using queues that can solve the problem of time delay of single processing method, cost increase of parallel processing method, and waste of manpower by utilizing multiple bots connected by wide area network Design and implement. Methods/Statistical analysis : This study designs and analyzes applications that run on independent systems based on multi-threaded system configuration using queues. Findings : We propose a multi-threaded web crawler design using queues. In addition, the throughput of web documents can be analyzed by dividing by client and thread according to the formula, and the efficiency and the number of optimal clients can be confirmed by checking efficiency of each thread. The proposed system is based on distributed processing. Clients in each independent environment provide fast and reliable web documents using queues and threads. Application/Improvements : There is a need for a system that quickly and efficiently navigates and collects various web sites by applying queues and multiple threads to a general purpose web crawler, rather than a web crawler design that targets a particular site.

• The Korean Journal of Applied Statistics
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• v.32 no.2
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• pp.229-263
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• 2019

The Korean fertility rate has been declining rapidly since 2000 with the fertility rate among provinces following a uniform tendency. In particular, the province-specific fertility rate is an essential tool for local governments to prepare local policies for low fertility aging policy, education and welfare policies. However, there is limitation on how to reflect different trends on the province-specific fertility rate because the KOSTAT's (2017) province-specific fertility rate projection estimates information use the national average birth rate date of vital statistics for the last 10 years (5 years). In this study, we propose an improvement plan that simultaneously considers important stable pattern maintenance and provincial fertility rate differentiation for an annual birth rate estimation. The method proposed in this study (proposal 1 and 2) can reflect birth rate changes from past to present and national and provincial differences by age that use time series data of the annual fertility rate. Proposal 3 also reflects the unique fertility rate trend from the past to the present by age according to province regardless of the relationship with the national trend. Therefore, it is preferable to use a relationship to the national rate when predicting the birth rate, as in proposals 1 and 2 because the national and the provincial fertility rate pattern are similar. These proposals show improved stability in terms of age-specific fertility rates.

• Informatization Policy
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• v.26 no.1
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• pp.83-105
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• 2019

The purpose of this study is to analyze the domestic and overseas laws and regulators' decisions related to zero-rating (ZR) practices through a comparative approach and to support development of the ex-post regulation. Although most countries are adopting ex-post regulatory approaches toward the globally increasing ZR practices, there is no uniform standards or an approach to consider when deciding whether to allow mobile ISPs' zero-rating practices in the market. However, in recent years, some countries have been improving their policy transparency with respect to ZR through enacting and amending relevant laws as well as making trial decisions. The comparative analysis shows that each country investigates restriction of the user choice and ISPs' adherence to the obligation of non-discrimination in order to judge whether the user benefits are damaged by the ZR practices. It also investigates ISP-CP's market positioning and ISP's vertical integration for profit squeeze to find out whether they harm fair competition with ZR practices in the mobile ecosystem. Based on the results of the comparative analysis, we suggest the desirable ZR regulatory directions under the domestic legislative status.

• Journal of Korean Medical Ki-Gong Academy
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• v.20 no.1
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• pp.118-147
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• 2020

Objective : The purpose of this study is to understand trends of pelvic correction therapy in Korea and to assist research activities on pelvic correction therapy. Also, this study selected and presented indicators for measuring pelvic slope to help ensure consistent studies with uniform indicators in future studies related to pelvic correction. Methods : The following keywords "골반", "골반 교정", "골반 변위" "Pelvic correction" were searched on three specialized search sites (RISS, NAI, DBpia). Trends in pelvic correction therapy were analyzed through the selected researches suitable among these searched researches in an overview format. Results : 1. A total of 7,806 studies were searched and a total of 268 studies were finally selected. 2. Studies began in 1977 and have been actively studied until recently, with 35 studies in 2017 being the most recent trend since 2000. 3. In the results according to the Main Field of Research, the 'Arts and Kinesiology'(113, 42.16%) and 'Medicine and Pharmacy'(103, 38.43%) were the most in order. To the Middle Field, the 'Kinesiology was the largest with 96(35.82%) studies. 4. In the results according to the study design, 'Pre-Post Test(PPT)' was the largest with 107 studies. 5. In the results according to the Intervention, 'Exercise' was the largest with 165 studies, of which 'Pilates' and 'Yoga' in 'Training' was the largest. 6. Among the evaluation method, the 'Pelvic Index' was used 146 times, followed by 'Spinal Alignment (99)', 'Other Joints (93)', and 'Kinetic Specialized Measurement Test (56)'. 7. Among the evaluation methods, the pelvic slope measurement indicators were PT (58), PH (48), Pelvic Torsion (40), Iliac Crest (38), ASIS-PSIS distance/angle (27), and Pelvic Width (I.W., I.L., S.W) (25) in order. 8. The journals that published the most researches were KJSS(Korean Alliance For Health, Physical Education, Recreation, And Dance;9), and JKPT(Korean Physical Therapy;9). Among the University, the Graduate School of Silla University published the most papers (12). 9. The author who published the most studies were Seungjin Park(3), the co-authors were Hoseong Lee, Gideok Park, Seongsu Bae(3), and the Thesis-Director Gyeongok Lee(7). Conclusions : 1. Studies on pelvic correction treatment continue to increase every year. 2. The main academic field of pelvic correction is 'Sports', 'Physical Therapy', and 'Medical Science'. 3. The most chosen research design method in the study on pelvic correction treatment was 'Pre-Post Test(PPT)', primarily as an intermediary, Pilates and yoga during exercise therapy, and then Chiropractic during handcraft were used as multiple frequencies. 4. Among the various measurement method indicators of pelvic correction previously used, multiple frequency was taken up in the order of PT, PH, Pelvic Torsion, iliac crest, ASIS-PSIS distance/angle, and pelvic width (I.W.,I.L.,S.W). Typically, measurements through "ASIS-PSIS angle" are recommended and are considered as the most rational in clinical trials.