• 한국벤처창업학회:학술대회논문집
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• 2009.10a
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• pp.111-138
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• 2009

This research focuses on what factors determine firm's decisions on R&D outsourcing and how R&D outsourcing affect R&D performance. In recent years many firms outsource R&D activities instead of internalizing it. Thus, further investigation is necessary to find out this recent trend. Based on several theoretical background the study developed three determining factors of R&D outsourcing which are transactional level, firm level, and risk level. Transactional level composes of independent variables such as R&D cost saving, asset specificity and uncertainty which mainly comes from Transaction Cost Economics theory. Firm level composes of openness to technology from outer source, R&D capability, and outsourcing experience. Risk level composes of technological risk, cost-related risk and managerial risk. The result shows that R&D outsourcing is significantly related to cost saving aspect, low asset specific firms, firms without solid technological background, firms which are open to external technology, firms with other types of outsourcing experience, and firms which take technological risks. However, proposed relationship between degree of R&D outsourcing and R&D performance found out to be insignificant. This research is contribute to the field of outsourcing study since it will give guidance to managers who need to make strategic decisions on R&D outsourcing activities.

• Archives of Reconstructive Microsurgery
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• v.9 no.1
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• pp.1-5
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• 2000

The microsurgical reconstruction is necessary for elderly patients to treat severe trauma and head and neck tumor. The aim of this study is to analyze the risks of microvascular surgery and whether or not happening of more complication in elderly patients who are older than 60 years old and to suggest the solution of the complication. The retrospective study included 41 elderly patients who underwent treatment of 44 microsurgical reconstructions among total 271 cases of microsurgical reconstruction from July, 1988 to December, 1998. Their ages ranged from 61 years to 79 years. There were 26 males and 15 females. The involved sites were 23 head and necks, 13 upper gastrointestinal tracts, 3 lower extremities, 1 chest and 1 sacral region. The causes of microsurgical reconstruction were 36 head and neck tumors, 2 radionecrosis, 2 traumas and 1 melanoma in lower limb. The used flaps were 14 radial forearm flaps, 13 jejunal flaps, 10 latissimus dorsi muscle flaps, 3 rectus abdominis muscle flaps, 2 lateral arm flaps, 1 scapular flap, and 1 iliac osteocutaneous flap. They had medical problems which were 29 tobacco abuse, 14 hypertensions, 13 alcohol abuse, 10 chronic obstructive pulmonary diseases, 7 diabetes mellituses, 3 ischemic heart diseases. All patients have had successful results without specific complications except 3 cases of free flap failure and 3 perioperative death. The causes of 3 flap failures were 2 flap necrosis due to arterial insufficiency and 1 flap loss due to secondary infection. All of these cases were treated with secondary free flap surgery. However 3 patients died perioperatively due to 2 respiratory arrests and 1 sepsis. It was not related to operate microsurgical reconstruction itself, but was correlated with the complication of postoperative care after head and neck surgery. We conclude that plastic surgeons consider the importance of prevention of expected complication as thorough analysis of operative risk factor and appropriate treatment. We had to select the donor and recipient vessel appropriately to perform successful microsurgery in elderly patients and consider vein graft and end-to-side anastomosis to reduce complication if necessary. In addition, we emphasize the importance of pre, peri and postoperative care in head and neck cancer patients to reduce postoperative complication and morbidity.

• Journal of environmental and Sanitary engineering
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• v.7 no.2
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• pp.95-110
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• 1992

Much progress has been made in understanding the subcellular events of the human lung injuries after acute exposure to environmental air pollutants. Host of those events represent oxidative damages mediated by reactive oxygen species such as superoxide, hydrogen peroxide, and the hydroxy, free radical. Recently, nitric oxide (NO) was found to be endogenously produced by endothelial cells and cells of the reticulo-endothelial system as endothelialderived relaxation factor (EDRF) which is a vasoactive and neurotransmitter substance. Together with superoxide, NO can form another strong oxidant, peroxonitrite. The relative importance of exogenous sources of $N0/N0_2$ and endogenous production of NO by the EDRF producing enzymes in the oxidative stresses to the heman lung has to be elucidated. The exact events leading to chronic irreversible damage are still yet to be known. From chronic exposure to oxidant gases, progressive epithelial and interstitial damages develop. Type I epithelial cells become thicker and cover a smaller average alveolar surface area while thee II cells proliferate instead. Under acute damages, the extent of loss of the alveolar epithelial cell lining, especially type II cells appears to be a good predictor of the ensuing irreversible damage to alveolar compartment. Interstitial matrix undergo remodeling during chronic exposure with increased collagen fibers and interstitial fibroblasts. However, Inany of these changes can be reversed after cessation of exposure. Among chronic lung injuries, genetic damages and repair responses received particular attention in view of the known increased lung cancer risks from exposure to several air pollutants. Heavy metals from foundry emission, automobile traffics, and total suspended particulate, especially polycystic aromatic hydrocarbons have been positively linked with the development of lung cancer. Asbestos in another air pollutant with known risk of lung cancer and mesothelioma, but asbestos fibers are nonauthentic in most bioassays. Studies using the electron spin resonance spin trapping method show that the presence of iron in asbestos accelerates the production of the hydroxy, radical in vitro. Interactions of these reactive oxygen species with particular cellular components and disruption of cell defense mechanisms still await further studies to elucidate the carcinogenic potential of asbestos fibers of different size and chemical composition. The distribution of inhaled pollutants and the magnitude of their eventual effects on the respiratory tract are determined by pollutant-independent physical factors such as anatomy of the respiratory tract and level and pattern of breathing, as well as by pollutant-specific phyco-chemical factors such as the reactivity, solubility, and diffusivity of the foreign gas in mucus, blood and tissue. Many of these individual factors determining dose can be quantified in vitro. However, mathematical models based on these factors should be validated for its integrity by using data from intact human lungs.

• Journal of The Korean Dental Society of Anesthesiology
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• v.13 no.1
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• pp.13-18
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• 2013

CATCH 22 syndrome is a one of the most common chromosome microdeletion syndrome with multiple organ anomalies in humans, with an incidence of approximately 1:4,000 to 1:5,000 live births. It is caused by a microdeletion of 1.5 to 3.0 megabases on the long arm of chromosome 22. The phenotypic spectrum of this disorder is wide and various. A 19-year-old patient who showed delayed growth and development (Height; 110 cm, Weight; 18 kg) was referred to our department for the treatment of dental cavities. She was diagnosed as CATCH 22 syndrome in 2004. Physical examination revealed hypertelorism, a short philtrum, thick reflected lips and a small mouth. She underwent cleft palate surgery at 1 year of age and heart valve surgery due to the cardiovascular abnormality at 13 years of age. Convulsive seizures had persisted until 5 years ago but are well controlled at present. Oral examination showed poor oral hygiene, crowding, prolonged retention on #65, 75 and dental cavities on #16, 21, 65, 26, 36, and 46. Cavity treatment and prophylaxis were performed under general anesthesia. Also continuous follow-up checks have been carrying out with the periodic prophylaxis and dental home education. Problems with numerous cavities and gingivitis which can lead to specific risks are common for CATCH 22 syndrome patients. It is therefore of great importance that these patients are referred to foremost physician and dental specialist for the oral care. In addition, preventive treatment targeting the risk of dental cavities and gingivitis is especially important and, as the syndrome involves many different medical problems, the dental treatment should be carried out in collaboration with the patient's physician.

• Korean Journal of Psychosomatic Medicine
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• v.27 no.2
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• pp.173-180
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• 2019

Objectives : Loneliness is associated with negative mental and physical health. However, little is known about the risk factors of loneliness in the Korean elderly living alone. The aim of this study was to examine sociodemographic and social network related risks for loneliness among the elderly living alone. Methods : This is a cross-sectional study that enrolled 1,091 subjects who are the community-residing elderly living alone. Sociodemographic status, medical condition, cognition, mood disorder and levels of loneliness were collected using a self-administered questionnaire and a specific semi-structured interview conducted by a trained nurse. Descriptive statistics were used to analyze data regarding sociodemographic variable and loneliness. Univariate and Multivariate regression analyses were applied to examine factors associated with loneliness. Results : The mean score of loneliness was 3.8 (SD=1.7). No family contact (standardized β=0.115, p<0.001), no religious attendance (standardized β=0.057, p=0.028), no gathering with friends (standardized β=0.088, p=0.001) and high score of Short for of Geriatric Depression Scale (standardized β=0.502, p<0.001) were significantly associated with high loneliness in the elderly living alone. Conclusions : Family function, social network and depressive mood could be significant risk factors for high loneliness in the elderly living alone. Public health promotion efforts to reduce loneliness should focus on improving family function, social network and decreasing depression.

• Journal of the Society of Disaster Information
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• v.11 no.1
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• pp.73-88
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• 2015

Due to the cases of recent global warming and unusual weather etc., large-scale natural disasters such as typhoons, floods, snow damage occur frequently across the continents such as Southeast Asia and North America, South America etc. and risks of earthquakes and tsunami are also increasing gradually in Korea which has been regarded as a safe zone and disaster types are also being diversified such as typhoons, floods, heat waves, heavy snow and damage scale is also enlarged. In addition, due to geographical characteristics or lack of infrastructure, disasters tended to occur intensively around a specific region or city in the past but disasters occur throughout the country in recent years so preparation for disaster prevention has emerged as an urgent challenge issue. Therefore, considering that the plan of obtaining the effective feedback function of disaster Information is very important in the proactive and software aspects for disaster reduction, this paper analyzed this three aspects of contents, procedural and contextual aspects and proposed the plan. First, in the content aspect, building disaster prevention information communication Infrastructure, building urban and regional disaster prevention system, obtaining concurrency and sharing of information and second, in the procedural aspect, active utilization of ICT(Information and Communication Technology) of the prevention stage, disaster prevention information collection and analysis reinforcement of the preparation stage, improvement of decision-making structure and field command system of the response stage, recovery system related information promotion of the recovery stage were proposed as alternatives and finally, in the contextual aspect, if disaster prevention information is effectively managed through maintenance of disaster prevention information related systems, obtaining domainality by disaster prevention work, improvement of the ability to judge the situation, obtaining comprehensive and feedback function etc, it is considered to significantly contribute to reducing natural disasters.

• Korean Journal of Community Nutrition
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• v.21 no.4
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• pp.378-385
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• 2016

Objectives: This study was conducted to investigate the association between sarcopenia and sarcopenic obesity and cardiovascular disease risk in Korean postmenopausal women. Methods: We analyzed data of 2,019 postmenopausal women aged 50-64 years who participated in the Korea National Health and Nutrition Examination Survey in 2008-2011 and were free of cardiovascular disease history. Blood pressure, height, and weight were measured. We analyzed the serum concentrations of glucose, total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol and triglyceride levels. Waist circumference was used to measure obesity. Appendicular skeletal muscle mass was measured by dual-energy X-ray absorptiometry. Sarcopenia was defined as the appendicular skeletal muscle mass/body weight<1 standard deviation below the gender-specific means for healthy young adults. The estimated 10-year risk of cardiovascular disease risk was calculated by Pooled Cohort Equation. Subjects were classified as non-sarcopenia, sarcopenia, or sarcopenic obesity based on status of waist circumference and appendicular skeletal muscle mass. Results: The prevalence of sarcopenia and sarcopenic obesity was 16.3% (n=317) and 18.3% (n=369), respectively. The 10-year risk of cardiovascular disease risk in the sarcopenic obesity group was higher ($3.82{\pm}0.22%$) than the normal group ($2.73{\pm}0.09%$) and sarcopenia group ($3.17{\pm}0.22%$) (p < 0.000). The odd ratios (ORs) for the ${\geq}7.5%$ 10-year risk of cardiovascular disease risk were significantly higher in the sarcopenic obesity group (OR 3.609, 95% CI: 2.030-6.417) compared to the sarcopenia group (OR 2.799, 95% CI: 1.463-5.352) (p for trend < 0.000) after adjusting for independent variables (i.e., exercise, period of menopausal, alcohol use disorders identification test (AUDIT) score, income, education level, calorie intake, %fat intake and hormonal replacement therapy). Conclusions: Sarcopenia and sarcopenic obesity appear to be associated with higher risk factors predicting the 10-year risks of cardiovascular disease risk in postmenopausal women. These findings imply that maintaining normal weight and muscle mass may be important for cardiovascular disease risk prevention in postmenopausal women.

• Korean Journal of Head & Neck Oncology
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• v.19 no.2
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• pp.148-157
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• 2003

Background and Objectives: Individual genetic susceptibilities to chemical carcinogens have been recognized as a major important host factors in human cancers. The cytochrome P450 family (CYPs) and glutathione S-transferase(GST) have been reported to be associated with risks to the smoking-related human cancers. Inactivation of tumor suppressor genes like p53 playa key role in tumor progression. The purpose of this study is to demonstrate an association between p53 overexpression and the prevalence of the genetic polymorphisms of CYP1A1 and GSTs in Korean head and neck squamous cell carcinoma (HNSCC). Materials and Methods: The polymorphisms of CYPIA1 and GSTs were analyzed by PCR and PCR-RFLP in 98 Korean head and neck squamous cell carcinoma patients. The expression of p53 was analyzed by immunohistochemistry with anti-p53 Ab (DO7). Results: Overexpression of p53 detected in 45.9% of HNSCC. The odds ratio for p53 overexpression in GSTM1(-), GSTT1(-), GSTP1(val/val) and CYP1A1(val/val) were 1.53, 1.83, 1.17 and 1.47, respectively. Among the combined genotypes, the odds ratio of the CYP1A1 val/val, GSTM1 (-), CYP1A1 val/val, GSTT1(-), and CYP1A1 val/val, GSTT1(-) were 2.0, 2.34 and 4.68, respectively. Conclusion: Based on our results, it might be suggested that p53 overexpression is slightly increased in GSTM1(-), GSTT1(-), GSTP1 val/val, CYP1A1 val/val genotypes. The further study is needed to evaluate the relationship and mechanism between the p53 overexpression and the specific CYP1A1 and GSTs genotypes.

• Journal of Korean Society of Forest Science
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• v.104 no.4
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• pp.632-639
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• 2015

Working in the forest would require a wide range of skills and experience for specific tasks which involve with a high level of risks to worker's safety. However, there has been a concern on the current standard wage system for forest workers because it does not effectively reflect the characteristics of typical working conditions in the forest. In addition, the current standard wages for forestry workers was estimated based on the construction industry's wage system. Therefore, the purpose of this study is to assess a current wage system through the mail survey method and to develop a new wage system for forest worker which effectively reflects skill sets and experience required for successful completion of the work in the forest. We mailed the survey questionnaire consisting of 19 questions to 659 forest workers and received 188 responses resulting in a 28.5% response rate. The results showed that the current average optimal wages of forest worker, special worker and feller were 97,680won/day, 127,559won/day and 152,403won/day, respectively though there were variations depending on the regions. In developing the new standard wage system, this study suggest the current work types(worker, special worker and feller) could be divided into 5 work types (forest-environment workers, forest operations in beginner, forest operations in intermediate, forest operations in advanced and forest equipment operator) reflecting specialty of forest operation thereby stabilizing the new wage system for forest workers.

• Journal of Soil and Groundwater Environment
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• v.16 no.1
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• pp.32-41
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• 2011

By using a newly developed Korean risk-based corrective action (K-RBCA) software (K-RBCA) and the RBCA Tool Kit, risk assessment was performed on a site that was contaminated with aromatic hydrocarbons and heavy metals. Eight chemicals including benzene, ethylbenzene, xylenes, naphthalene, benz(a) anthracene, benzo(b) fluoranthene, benzo(a) pyrene, and arsenic that exceeded the US EPA Soil Screening Level were chosen as the target pollutants. A conceptual site model was constructed based on the site-specific effective exposure pathways. According to the RBCA Tool Kit the carcinogenic risk of arsenic was larger than $10^{-6}$, which is the generally acceptable carcinogenic risk level. The K-RBCA estimated the same level of carcinogenic risk for arsenic. With the RBCA Tool Kit, the carcinogenic risk of benzo(a) pyrene was estimated to be about $1.3{\times}10^{-6}$. However, with the K-RBCA benzo(a) pyrene did not exhibit any risk. The inconsistency between the softwares was attributed to the different fundamental settings (i.e., medium division) between the two softwares. While the K-RBCA divides medium into surface soil, subsurface soil, and groundwater, the RBCA Tool Kit divides medium into only soil and groundwater. These differences lead to the different exposure pathways used by the two softwares. The K-RBCA considers the exposure pathways in surface soil and subsurface soil separately to estimate risk, however, the RBCA Tool Kit considers the surface soil and subsurface soil as one and uses the integrated exposure pathways to estimate risk. Thus the resulting risk is higher when the RBCA Tool Kit is used than when the K-RBCA is used. The results from this study show that there is no significant difference in the risks estimated by the two softwares, thus, it is reasonable to use the K-RBCA we developed in risk assessment of soil and groundwater. In addition, the present study demonstrates that the assessor should be familiar with the characteristics of a contaminated site and the assumptions used by a risk assessment software when carrying out risk assessment.