• Tunnel and Underground Space
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• v.19 no.3
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• pp.236-247
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• 2009

Overpopulation has significantly increased the use of underground spaces in urban areas, and led to the developments of shallow-depth underground space. Due to unexpected rock fall, however, it is very necessary to understand and categorize the rock mass behaviors prior to the tunnel excavation, by which unnecessary casualties and economic loss could be prevented. In case of cave-in, special attention should be drawn since it occurs faster and greater in magnitude compared to rock fall and plastic deformation. Types of cave-in behavior are explained and categorized using seven parameters - Uniaxial Compressive Strength (UCS), Rock Quality Designation (RQD), joint surface condition, in-situ stress condition, ground water condition, earthquake & ground vibration, tunnel span. This study eventually introduces a new index called Cave-in Behavior Index (CBI) which explains the behavior of cave-in under given in-situ conditions expressed by the seven parameters. In order to assess the mutual interactions of the seven parameters and to evaluate the weighting factors for all the interactions, survey data of the experts' opinions and Rock Engineering Systems (RES) were used due to lack of field observations. CBI was applied to the tunnel site of Seoul Metro Line No. 9. UDEC analyses on 288 cases were done and occurrences of cave-in in every simulation were examined. Analyses on the results of 288 cases of simulations revealed that the average CBI for the cases when cave-in for different patterns of tunnel support was estimated by a logistic regression analysis.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.5
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• pp.467-471
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• 2015

Thus far, solders used in electronics remain lead-based. Pb-free solutions in electronic components and systems are receiving increased attention in the semiconductor and electronics industries. Pb-free materials currently in used are Sn-37Pb, Sn-4Ag and Sn-4Ag-0.5Cu/Ni plate joints. In this study, solder alloys were used at high temperatures for artificial aging processing that was performed at $150^{\circ}C$ for 0hr, 100hr, 200hr, 400hr, 600hr and 1000hr. The SP test was conducted at $30^{\circ}C$ and $50^{\circ}C$. As a result, the maximum shear strength of all the specimens decreased with the increase in artificial aging time and temperature of the SP test. In addition, Pb-free solders showed higher total fracture energy compared with Sn-37Pb at high temperatures. The mechanical properties of Sn-4Ag-0.5Cu solder/Ni plate joints remained in excellent conditions in electronic parking systems at high temperatures.

• Journal of Preventive Medicine and Public Health
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• v.32 no.2
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• pp.113-122
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• 1999

Objectives: The purpose of this study was to describe the trends of original research in the Korean Journal of Preventive Medicine, and to evaluate the quality of original articles about lead poisoning. Method: The data for the analysis of trends in preventive medicine research was taker from a total of 829 original articles published in the Korean Journal of Preventive Medicine from 1968 to 1997, The qualitative meta-analysis was measured against a checklist of evaluation criteria, which were divided into 10 categories, with 46 articles on lead poisoning. The evaluation process was performed independently by two evaluators, Results: The number of articles per 100 members over the study period increased by almost 4 pieces in the early 1980s, and by more than 9 pieces in the mid-1990s. In the major classifications of subjects, environmental and industrial health, epidemiology and health statistics, and health policy and management published 370 pieces (44.0%), 137 pisces (16.5%), 322 pieces (38.9%) respectively. In the order of the number of articles, five themes about health significance, including metal exposure (73 pieces), diseases associated with exposure to organic solvents (45 pieces), air pollution (36 pieces), maternal and child health (32 pieces), and occupational health (3D pieces) received consistent attention throughout the years $1968\sim1997$. The overall mean score of article qualify about lead poisoning was 37.8 out of 50. Of the articles any information on the purpose and hypothesis described well, Of those the originality of the subjects, the form of article's (including tables and figures), and the number of inappropriate words of abstracts showed very low score. For multiple regression analyses, the number of joint research institutes and the acceptance of research grants about the article quality were statistically significant. Conclusions: The number of original research reports in the Korean J Prev Med has recently increased and their subjects bave diversified. Of the basis of this study, the articles need improvement in the areas of abstracts, tables and illustrations (figures), etc. The Korean Society for Preventive Medicine will revise contribution regulations for manuscripts submitted to the Korean J Prev Med. Future studies should address these issues and perform the quantitative mata-analysis about the specific subjects including the quality of articles.

• Journal of Biomedical Engineering Research
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• v.31 no.3
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• pp.199-209
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• 2010

The locking compression plates-distal femur(LCP-DF) are being widely used for surgical management of the extra-articular complex fractures of the distal femur. They feature locking mechanism between the screws and the screw holes of the plate to provide stronger fixation force with less number of screws than conventional compression bone plate. However, their biomechanical efficacies are not fully understood, especially regarding the number of the screws inserted and their optimal configurations. In this study, we investigated effects of various screw configurations in the shaft and the condylar regions of the femur in relation to structural stability of LCP-DF system. For this purpose, a baseline 3-D finite element (FE) model of the femur was constructed from CT-scan images of a normal healthy male and was validated. The extra-articular complex fracture of the distal femur was made with a 4-cm defect. Surgical reduction with LCP-DF and bone screws were added laterally. To simulate various cases of post-op screw configurations, screws were inserted in the shaft (3~5 screws) and the condylar (4~6 screws) regions. Particular attention was paid at the shaft region where screws were inserted either in clustered or evenly-spaced fashion. Tied-contact conditions were assigned at the bone screws-plate whereas general contact condition was assumed at the interfaces between LCP-DF and bone screws. Axial compressive load of 1,610N(2.3 BW) was applied on the femoral head to reflect joint reaction force. An average of 5% increase in stiffness was found with increase in screw numbers (from 4 to 6) in the condylar region, as compared to negligible increase (less than 1%) at the shaft regardless of the number of screws inserted or its distribution, whether clustered or evenly-spaced. At the condylar region, screw insertion at the holes near the fracture interface and posterior locations contributed greater increase in stiffness (9~13%) than any other locations. Our results suggested that the screw insertion at the condylar region can be more effective than at the shaft during surgical treatment of fracture of the distal femur with LCP-DF. In addition, screw insertion at the holes close to the fracture interface should be accompanied to ensure better fracture healing.

• Journal of Distribution Science
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• v.9 no.2
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• pp.13-24
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• 2011

With the increasing market share of retailer brands, many authors have paid considerable attention to retailer brands. Before market liberalisation in 1996 in Korea, retailer brand market was led by the supermarket retailing format, although the first retailer brand product was developed by the department store format. In parallel with the entry of foreign multiple retailers, the retailer brand market has experienced rapid growth. Particularly, the expansion of Tesco UK with well-established retailing know-how into Korea has encouraged Tesco Korea to actively get involved in retailer brand program. As a result, Tesco Korea has led retailer brand market in the Korean marketplace. The research starts with the question of why Tesco Korea has achieved such a higher retailer brand share. Accordingly, this study is to explore how Tesco UK has transferred its own retailing knowledge into Tesco Korea, in terms of retailer brand program development. In order to explore why the retailer brand share of Tesco Korea is higher than that of its counterparts, the author adopted in-depth interview with prepared-questions and store observation as a research methodology. To examine working process as well as information flows within Tesco Korea and from UK to Korea, in-depth interview method is one of the most suitable research methodologies, because of the difficulty of quantifying information or data related to work flows. In addition, to increase the validity of information, the researcher had interviews with Tesco Korea supplier and store personnel. Based on these research techniques, this research explored how Tesco UK has influenced or advised Tesco Korea, particularly, from the point of view of knowledge transfer. Since the entry of Tesco UK into Korea as a joint-venture, the retailer brand market share of Tesco Korea has continuously increased. It would be expected that Tesco UK has helped Tesco Korea to settle down in the Korean market. During interviews with Tesco and a Tesco supplier, the researcher found that Tesco Korea has obviously taken an advantage of retailing know-how created by Tesco UK. Furthermore, the retailer brand development and handling process of Tesco Korea has been operated with the help of Tesco UK. This might mean that Tesco UK has directly or indirectly an impact on the improvement of Korean retailer brand development skills. As a mechanism to transfer retailing knowledge developed in the home market into the host market, one of the international retailers, Tesco UK has adopted many different ways such as annual meeting, trading meeting to import or export own retailer brand products, offering of operation manual developed by Tesco UK and buyer cooperation between Tesco UK and Korea, in order to share information. Through these communication techniques, the knowledge of Tesco UK has been transferred to Tesco Korea. This research accordingly suggests that retailer brand market share is apparently related to how sophisticated or advanced the knowledge of the retailer brand development and handling process of retailers are. It is also demonstrated by this research that advanced development and handling skills make a considerable contribution to increasing retailer brand share in markets with a lower share or no presence of retailer brands.

• Journal of Korea Technology Innovation Society
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• v.10 no.2
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• pp.230-254
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• 2007

Scientometrics means the metrics of science, and it plays a role in the measurement of scientists' activities by using research results like papers. Objective numerical values or indicators obtained by scientometric analysis may make a significant contribution to correct evaluation by excluding political or relationship bias or revealing significant researchers or their research fields that have been assessed relatively lower for their performance. In the period when the scale of technology was relatively large, such as for the development of heavy chemistry, it was possible to make a not-bad selection by an assessment made only with the intuition of the assessor. However, it is nearly impossible for experts with a narrow knowledge in a field to judge the direction of change correctly as the current science technology changes rapidly and tremendously. Even in an assessment of research performance of researchers or research institutions, only some notable researchers are able to attract attention owing to the Metthew effect, and the majority who have accumulated research results in depth are not able to receive reasonable research funding. Therefore, it might be natural that there is a growing need for assessment using scientometrics. The purpose of this research is to suggest some applicable scientometric techniques for an assessment of research performance to science and technology researchers and policy planners. In order to accomplish this, we used a frequency analysis of papers and its citations to assess the research performance of researchers, institutions, and countries for OLED technology as a case study. Furthermore, we position detailed technologies for OLED technology as arriving, growing, maturing, and declining technology by utilizing several network analysis techniques, make groups with researchers and institutions of same research interest. And we review the current international joint research of Korea, China, and Japan, who are in a competitive relationship. Also, at the end of each analysis result, we describe what kind of assessment should be available to Korean policy planners and research managers for such scientometric analysis results.

• Journal of Korean Medicine Rehabilitation
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• v.27 no.3
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• pp.61-70
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• 2017

Objectives The purpose of this review is to analyse the trend in papers related with Korean Medicine Treatment after musculoskeletal disorder surgery. Methods We reviewed Korean Medicine papers by searching Korean web databases 'Korea Traditional Knowledge Portal', 'Scientific and Technological Information Integration Service (NDSL)', 'Academic Research Information Service (RISS)', 'Korea Medical Informati on Portal (OASIS)'. We classified the papers by the year of publishment, the title of journals, the type of study, surgery region, chief complain after surgery, main treatment, periods after surgery, assessment for outcomes. Results 1. Korean Medicine treatment after musculoskeletal disorder surgery has received more attention than in the past and there are attempts to do various studies besides the case reports. 2. 41 research papers were divided in to 3 original articles, 3 review articles, 35 case reports. But almost presented a low level of evidence. 3. Pain was the most common symptom after the musculoskeletal disorder surgery. Pain should be the primary goal of Korean rehabilitation treatment after musculoskeletal disorder surgery. 4. Assessment tools for outcome were concentrated in questionnaries, VAS and NRS. In order to evaluate better, it is necessary to evaluate the overall condition of the patient such as the quality of life evaluation and patient satisfaction. Conclusions In this study, we expect that the development and clinical application of Korean rehabilitation treatment program after musculoskeletal disorder surgery will be actively pursued.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.10 no.1
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• pp.76-90
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• 1999

This study was performed 1) to compare the nature of the synchronized behaviors in mother-child plays between autistic and normal groups quantitatively and qualitatively and 2) to identify the behavioral data to improve synchrony. The subjects were consisted of 20 mother-child pairs, 10 for each autistic group(AG) and normal group(NG). The developmental age of two groups was under 24 months old and equally matched. Data were collected by video-taped mother-child free play and analyzed with Wilcoxon Rank Sign(Sum) Test, Spearman Correlation Coefficient, Scheffe's Test, and Content Analysis. The score on synchronized behaviors of AG was significantly lower than that of NG(p<.05). As time progressed, the difference was much higher between the 2 groups. And the structure of motherchild plays in AG was poor and most of the interactions were discontinued as 1 or 2 episodes. On the other hand, mother-child plays in NG were enriched and became somewhat like game or play. The score of mother's growth-fostering nurturing behaviors showed positive relation to synchrony and much highly related to the group of 16 months-old or above. Mother's laughing and patting responses and pausing to get the child's initiative were especially related highly to synchronized behaviors. In conclusion, these mother's growth-fostering nurturing behaviors should be stressed at the mother-child interactions and also well structured therapeutic play with considering in children's developmental level should be given.

• Journal of Science and Technology Studies
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• v.4 no.1 s.7
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• pp.1-30
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• 2004

In this paper, I have attempted to show how the environmental controversy surrounding the Saemangeurn Reclamation Project in Korea has been framed as narrow scientific debates. First of all, science, or specifically the Expert Review Pane, has played dual roles in the controversy. On the one hand, it has contributed to illuminating the future environmental impacts of reclamation, by so doing, to providing a momentum to reconsider the project. This has significant meaning that environmental concerns successfully checked the symbolic national project of developmental era through adopting a joint-investigation scheme that guaranteed participation of environmental groups on an equal footing with the government. On the other hand, by limiting the scope and participants of discussion, it fundamentally blocked the possibilities of public debates and deliberative decision-making with full considerations of the political, social, and cultural aspects of the controversy. I have shown that this is due to the realist belief shared by both the developers and the environmentalists in Korea that 'proper' science would disclose the truth. Environmental groups, in particular, were naive in evaluating the role of scientific expertise in the controversy and neglected the political role of the Expert Review Pane as a ritual. In opposition to the realist argument, I have shown through the analysis of the water quality debates concerning the future fresh water lakes that scientific 'facts' were not discovered but constructed through complex negotiations, conflicts, and compromises among related actors. The framing of the controversy as an experts' debate has resulted in the exclusion of an important actor from the discussion. Little attention has been paid throughout the controversy to the very people who have lived in the Saemangeum area for generations and will lose their livelihood all together soon. About 20,000 fishermen are living on the Saemangeum tidal flats.

• The Journal of the Korean bone and joint tumor society
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• v.19 no.1
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• pp.20-27
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• 2013

Purpose: The purpose of this study was to evaluate the oncologic outcomes of parosteal osteosarcoma (POS) and to ascertain the fates of patients after local recurrence (LR). Materials and Methods: The authors retrospectively reviewed 22 POS patients with an average follow-up of 114 months (range: 36-235 months). Seven of the 22 patients were referred after LR. There were 17 Stage IB and 5 Stage IIB (G2, 2; dedifferentiation, 3). Tumors were located in the femur (11) and in other locations (11). Initial surgical margins were wide in 10, marginal in 5, and intralesional in 7. Correlations between clinico-pathologic variables and LR and clinical courses after LR were evaluated. Results: The 10-year overall survival rate was 85.7%. Three (14%) patients developed distant metastasis and all of them succumbed to the disease. Nine (41%) patients developed LR. Tumor location, resection type, and surgical margin were found to be correlated with LR. At final follow-up, 7 of the 9 patients that experienced local failure achieved no evidence of disease. Conclusion: A substantial risk of misdiagnosis exists, especially for POS in other than a femoral location. Recurrent tumor re-excision is possible in most cases; however, patients with an aggressive recurrence pattern deserve special attention.