• Radiation Oncology Journal
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• v.2 no.2
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• pp.287-297
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• 1984

The normal intracranial structures are relatively resistant to therapeutic radiation, but may react adversely in a variety of ways, and the damage to nerve tissue may be slow in making its appearance, and once damage has occured the patient recovers slowly and incompletly. Therefore, it is important to consider the possibility of either recurrent tumor or late adverse effect in any patient who has had radiotherapy. The determination o( rnorphological/pathological correlation is very important to the therapeutic radiologist who uses CT scans to define a treatment volume, as well as to the clinician who wishes to explain the patient's clinical state in terms of regress, progression, persistence, or recurrence of tumor or radiation-induced edema or necrosis, The authors are obtained as following results ; 1. The field size(whole CNS, large, intermediate, small field) was variable according to the location and extension of tumor and histopathologic diagnosis, and the tatal tumor dose was 4,000 to 6,000 rads except one of recurred case of 9,100 rads. The duration of follow up CT scan was from 3 months to 5 year 10 months. 2, The histopathologic diagnosis of 9cases were glioblastoma multiforme(3 cases), pineal tumor (3), oligodendroglioma (1), cystic astrocytoma (1), pituitary adenoma (1) and their adverse effects after radiation therapy were brain atrophy (4 cases) , radiation necrosis(2), tumor recurrence with or without calcification (2), radiation·induced infarction (1). 3. The recurrent symptoms after radiation therapy of brain tumor were not always the results of regrowth of neoplasm, but may represent late change of irradiated brain. 4. It must be need that we always consider the accurate treatment planning and proper treatment method to reduce undesirable late adverse effects in treatment of brain tumors.

• Journal of Applied Biological Chemistry
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• v.63 no.3
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• pp.283-290
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• 2020

Oxidative stress is one of the contributors of neurodegenerative disorders including Alzheimer's disease. According to previous studies, Aster yomena (Kitam.) Honda (AY) possesses variable pharmacological activities including anti-coagulant and anti-obesity effect. In this study, we aimed to determine the neuroprotective effect of ethyl acetate fraction from Aster yomena (Kitam.) Honda (EFAY) against oxidative stress. Therefore, we carried out 3-(4,5-dimethylthiazol-2-yl)-2,3-diphenyl tetrazolium bromide, lactate dehydrogenase (LDH), and 2',7'-dichlorofluorescin diacetate assays in SH-SY5Y neuronal cells treated with hydrogen peroxide (H₂O₂). H₂O₂-treated control cells exhibited reduced viability of cells, and increased LDH release and reactive oxygen species (ROS) production compared to normal cells. However, treatment with EFAY restored the cell viability and inhibited LDH release and ROS production. To investigate the underlying mechanisms by which EFAY attenuated neuronal oxidative damage, we measured protein expressions using Western blot analysis. Consequently, it was observed that EFAY down-regulated cyclooxygenase-2 and interleukin-1β protein expressions in H₂O₂-treated SH-SY5Y cells that mediated inflammatory reaction. In addition, apoptosis-related proteins including B-cell lymphoma-2-associated X protein/B-cell lymphoma-2 ratio, cleaved caspase-9, and cleaved-poly (ADP-ribose) polymerase protein expressions were suppressed when H₂O₂-treated cells were exposed to EFAY. Our results indicate that EFAY ameliorated H₂O₂-induced neuronal damage by regulating inflammation and apoptosis. Altogether, AY could be potential therapeutic agent for neurodegenerative diseases.

• Journal of Korean Society of Transportation
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• v.28 no.5
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• pp.155-162
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• 2010

Elderly pedestrians account for more than 30% of all deaths in traffic accident and the number of elderly-related traffic accidents are increasing every year. Considering Korea's quickly aging society, drastic measures must henceforth be taken. Taking notice of the elderly living in and moving around the provinces, this research focused on analyzing the characteristics of elderly pedistrians' traffic accidents on provincial roads and developing an Equivalent Property Damage Only (EPDO) model. The authors collected 720 traffic accident data points from the police agency and developed the EPDO model, weighted differently by light injury, severe injury, and death using Multiple Regression Analysis. As a result, the speed of vehicles is the most influential variable in EPDO, and the shape of the road is significant as well. Therefore, various policies should be established like improving the environmental factors of provincial roads, like expanding speed-reduction treatments and signage, and setting up detours around areas of high elderly concentration.

• The Korean Journal of Franchise Management
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• v.12 no.2
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• pp.35-49
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• 2021

Purpose: The major objective of this study is to develop a model for the impact of franchisors' Gapjil (verbal·nonverbal Gapjil, abusing bargaining position, refusing transaction, false or exaggerated information, restrictive practices, unfair damage compensation) on franchisee's recontract intention. We also examine the mediating role of economic satisfaction and social satisfaction in the relationship between franchisors' Gapjil and franchisee's contract intention. Research design, data, and methodology: Data were collected from franchisee owners located nationwide in Korea. Out of 256 questionaires distributed, a total of 256 questionnaires were returned. After excluding 10 invalid respondent questionnaires, we coded and analyzed 246 valid questionnaires (effective response rate of 96.09%) using frequency, confirmatory factor analysis, correlations analysis, and structural equation modeling with SPSS 22.O and SmartPLS 3.0. Results: The findings of this study are summarized as follows: First, among the Gapjil of the franchisors, restrictive practices and unfair damage compensation had negative effects on economic and social satisfaction, but verbal and nonverbal Gapjil for economic and social satisfaction was not significant. Second, abusing bargaining positions and false or exaggerated information had negative effects on social satisfaction, but for economic satisfaction, found to be insignificant. Third, economic and social satisfaction had positive effects on the franchisee's recontract intention to the franchisor. Conclusion: The following implications of this study are as follows. First, the construct of Gapjil that occurs between the franchisors and the franchisees was first presented, and the franchisors' Gapjil is divided into interpersonal Gapjil and structural Gapjil. Second, the Gapjil of the franchisors can be an important predictor variable in maintaining and developing a long-term relationship between the franchisors and the franchisees. Third, solving conflict due to the Gapjil problem between franchisors and franchisees can be an important factor for franchisors and franchisees to co-survive and thrive in Korean franchise system. Fourth, this study suggest that managing the Gapjil of the franchisors was a important antecedent factor in maintaining long-term relationship between the franchisors and the franchisees. Therefore, this study will help franchisors formulate effective symbiotic marketing strategies to satisfy relationships with franchisees and consequently enhance long-term orientation.

• Smart Structures and Systems
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• v.32 no.1
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• pp.9-21
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• 2023

The parameters of civil engineering structures have time-variant characteristics during their service. When extremely large external excitations, such as earthquake excitation to buildings or overweight vehicles to bridges, apply to structures, sudden or gradual damage may be caused. It is crucially necessary to detect the occurrence time and severity of the damage. The unscented Kalman filter (UKF), as one efficient estimator, is usually used to conduct the recursive identification of parameters. However, the conventional UKF algorithm has a weak tracking ability for time-variant structural parameters. To improve the identification ability of time-variant parameters, an adaptive UKF with forgetting factor (AUKF-FF) algorithm, in which the state covariance, innovation covariance and cross covariance are updated simultaneously with the help of the forgetting factor, is proposed. To verify the effectiveness of the method, this paper conducted two case studies as follows: the identification of time-variant parameters of a simply supported bridge when the vehicle passing, and the model updating of a six-story concrete frame structure with field test during the Yangbi earthquake excitation in Yunnan Province, China. The comparison results of the numerical studies show that the proposed method is superior to the conventional UKF algorithm for the time-variant parameter identification in convergence speed, accuracy and adaptability to the sampling frequency. The field test studies demonstrate that the proposed method can provide suggestions for solving practical problems.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.5
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• pp.1-8
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• 2023

Marine and hydraulic structures are subject to durability damage not only due to the penetration of sea water but also due to the attachment of marine organisms. Therefore, in this study, we tried to develop an antifouling coating agent with self-cleaning function for marine concrete. It was confirmed that the antifouling coating agent mixed with AKD, cellulose nanofibers and BADGE had sufficient antifouling performance at a well hydrophobicity of around 140° in contact angle and an inclination angle of 15°. In the abrasion resistance test of the surface, only a maximum loss of 0.015 g occurred. In the durability test, as a result of the chloride ion permeation test, almost no chloride ion permeation occurred in the variable where the coating agent was applied, and carbonation and freeze-thaw damage also rarely occurred, so it was analyzed that it was effective in securing durability of concrete.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.2
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• pp.551-564
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• 2020

The fashion industry in Korea has grown into a core sector that contributes to the development of national industries, but it has shown negative growth due to the advent of a low-growth era. This study aims to explore core texts related to variable factors affecting the apparel industry in Korea (and the environmental change factors of apparel companies) by using network analysis from a diachronic point of view. In addition, we discuss the implications of enhancing the value of fashion industries in Korea based on articles in fashion newspapers over five years. The conclusion of this study is as follows. First, as a suggestion for political and economic aspects, the government should minimize the damage caused by political influence by presenting new policies, or by communicating about the practical aspects of geopolitical issues and changes linked to the fashion industry. Second, as a suggestion of socio-cultural aspects, it is necessary to reduce uncertainty about the future by establishing a strategic system through cooperation with institutions that can predict future directions. Third, as a suggestion for management changes in the apparel industry, apparel companies in Korea should recognize the importance of consciousness of promoting development for a better society from coexistence, rather than corporate profit.

• The Journal of the Korea Contents Association
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• v.20 no.5
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• pp.525-535
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• 2020

This study aims to evaluate the economic value of the heat wave watch/warning (HW/W) forecast provided by the KMA (Korea Meteorological Administration) for the public sector. Local govermenments of Korea currently use the HW/W forecasts as a major input variable to determine the preparative requisite level for reducing potential damage by extreme heat events. To assess the value of the HW/W, which is not a marketable commodity, a decision-making model taking into account the cost and loss was established. The 'cost' variable was defined as the heat wave countermeasures budget for Seoul and Busan in 2016, and the 'loss' variable was set as the amount of health insurance claims for those 65 and older obtained from the Health Insurance Review and Assessment Service. Using this model, the value of the HW/W in 2016 was calculated as KRW 4,133M and KRW1,090M for Seoul and Busan, respectively. In addition, if the KMA reduces the False Alarm of the HW/W by a single instance, the value will be increased by KRW 76.6M and KRW 16.8M for the two cities. The results of this study are useful in quantitatively estimation of the value of the HW/W forthe public sector.

• Journal of the Korea Concrete Institute
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• v.14 no.6
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• pp.942-948
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• 2002

When fresh concrete is exposed to low temperature, the concrete may suffer frost damage due to freezing at early ages and the strength development may be delayed. One of the solution methods to resolve these problems is to reduce freezing temperature of concrete by the use of chemical admixture called Accelerator for freeze protection. In this study we Investigate the effect on the strength development of cement mortar using accelerator for freeze protection with the variable curing condition. As the result of this study, the mortar using accelerator for freeze protection show continuously the strength development in curing condition of -5$^{\circ}C$. And the compressive strength under variable temperature condition was higher than constant temperature condition in same maturity.

• Journal of the Korea Institute of Building Construction
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• v.20 no.2
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• pp.137-145
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• 2020

The recent bridge construction projects demand thorough and systematic safety and risk management, due to the increase of risk factors following the introduction of new and complex construction methods and technologies. Among many types of damages that can occur in bridge construction projects, the damages to third parties who are not directly related to the existing property of the contractor construction project can also bring about critical loss in the project in order to compensate the damages. Therefore, risks that could be caused by the loss occurred to indemnify the third party damages should be clearly analyzed, although there are not subsequent amount of studies focusing on the issue. Based on the past record of insurance payment from domestic insurance companies for bridge construction projects, this study aimed to analyze the risk factors of bridge construction for loss caused to compensate the third-party damages happened in actual bridge construction projects and to develop a quantified and numerical predictive loss model. In order to develop the model, the loss ratio was selected as the dependent variable; and among many analyzed independent variables, the superstructure, foundation, flood, and ranking of contractors were the four significant risk factor variables that affect the loss ratio. The results produced can be used as an essential guidance for balanced risk assessment, supplementing the existing analysis on material losses in bridge construction projects by taking into account the third-party damage and losses.