• Corrosion Science and Technology
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• v.12 no.5
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• pp.233-238
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• 2013

In the case of casting materials or ductile materials for marine equipment, it is common to employ a surface modification for achieving cost reduction and improvement in strength. In particular, aluminium bronze ALBC3 exhibits excellent corrosion resistance, and thus widely used for marine application. However, application of the material under high-velocity seawater flow may induce electrochemical corrosion damage and physical damage such as cavitation erosion, leading to shorter service life of equipment. In this study, surface modification was carried out on ALBC3 alloy for different shot peening stand-off distances, and the physical hardness and electrochemical characteristics before and after modification were investigated. The results in each case showed the hardness increase in comparison with non-peened specimen, and the maximum hardness improvement(50 %) was found in 10 cm of shot-peening stand-off distance. It is observed that the electrochemical characteristics were irrelevant to application of shot peening.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.198-198
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• 2013

Metal-Oxide-Semiconductor (MOS)에서 사용되는 다양한 channel materials로 high electron mobility을 가지는 III-V compound semiconductor가 대두되고 있다 [1,2]. 하지만 이러한 III-V compound semiconductor는 Si에 비해 안정적인 native oxide가 부족하기 때문에 Si, Ge, Al2O3과 BeO 등과 같은 다양한 물질들의 interface passivation layers (IPLs)에 대한 연구가 많이 되고 있다. 이러한 IPLs 물질은 0.5~1.0 nm의 매우 얇은 physical thickness를 가지고 있고 또한 chemical inert하기 때문에 플라즈마 식각에 대한 연구가 되고 있지만 IPLs 식각 후 기판인 III-V compound semiconductor에 physical damage과 substrate recess를 줄이기 위해서 높은 선택비가 필요하다. 이러한 식각의 대안으로 원자층 식각이 연구되고 있으며 이러한 원자층 식각은 반응성 있는 BCl3의 adsorption과 low energy의 Ar bombardment로 desorption으로 self-limited한 one monolayer 식각을 가능하게 한다. 그러므로 본 연구에서는, III-V compound semiconductor 위에 IPLs의 adsorption과 desorption의 cyclic process를 이용한 원자층식각으로 다양한 물질인 SiO2, Al2O3 (self-limited one monolayer etch rate=about 1 ${\AA}$/cycle), BeO (self-limited one monolayer etch rate=about 0.75 ${\AA}$/cycle)를 얻었으며 그 결과 precise한 etch depth control로 minimal substrate recess 식각을 할 수 있었다.

• Journal of Conservation Science
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• v.36 no.1
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• pp.60-72
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• 2020

The Inscribed stones of Hanyangdoseong has been weathered for a long time because of external environment and living organisms. To establish a long-term conservation-management strategy for the inscription stones, the material characteristics of the inscription stones of Naksan Mountain Area were identified, and its deterioration state was diagnosed. Consequently, it was confirmed that the Inscription stones of Naksan Mountain Area mainly comprised coarse-to medium-grained pinkish granite and biotite granite, and, in part, comprised reddish granite, quartz porphyry, and aplite. Presently, the Inscription stones of Naksan Mountain Area, Hanyangdoseong, is undergoing a considerable decrease in physical properties because of physical, chemical, and biological weathering. Moreover, it has been confirmed that the type of damage, such as blistering, soiling, and dicolouration, on the surface shows a significantly high deterioration rate, and that conservation treatment might be required in future. In addition, because the possibility of damage recurrence is high even after the treatment, the conservation state must be regularly monitored.

• Journal of the Korean Institute of Rural Architecture
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• v.19 no.4
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• pp.77-85
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• 2017

In order to preserve beautiful coastal areas landscapes of Jeju Island's the landscape resource, Jeju Special Self-Governing Province is dedicated to protecting the landscape through legal regulations and deliberations. However, the Coastal Landscape of Jeju Island was continuously damaged by due to increased tourist and high development pressure. Based on buildings along the Coastal Road in Aeowal of Jeju Island, this study focused on Management Status of Coastal Areas Landscapes through the Analysis of Building Landscape Elements. As a result, 1) It was effective to limit the use and scale of buildings through legal regulations such as Use zoning. 2) The result of analysis on the physical landscape elements of buildings showed some of the them have the damage values despite passing the review of Architecture Committee. Therefore Landscape Policies required institutional maintenance. 3) As physical landscape Elements of buildings is a minimum quantitation criterion of not less than 1.5 for D/H, or less than a factor of $27^{\circ}$ for angle of elevation and not less than 7.8m for elevation blockage ratio was presented as a criterion for preventing damage to the minimum Coastal Landscape.

• The Korean Journal of Community Living Science
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• v.16 no.2
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• pp.27-37
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• 2005

The purpose of the research was to investigate the characteristics and related factors of dating violence. The subjects were 548 adolescents in high schools. The gathered information was analyzed by frequency, percent, 1-test, ANOVA, and correlation by using the SPSS 10.0 program. The results were as follows: (1) $58.6\%$ of respondents have had one or more dates with the other sex, so the association with the other sex is remarkably universal and natural. (2) In the case of physical violence, $18.5\%$ claimed that they have been injured in some ways, and $18.3\%$ said some kind of harm was done to them. (3) In terms of psychological violence, $32.8\%$ reported psychological damage and $35.6\%$ reported being harmed. (4) In terms of sexual violence, $20.8\%$ reported damage, while $18.2\%$ said they were harmed. (5) The relationship between physical, psychological and sexual violence has a significant relationship with the overall experience of violence. (6) When we looked at the social demographic factors, we found that boys rather than girls, and vocational school students rather than academic school students have more violent experiences.

• Conservation Science in Museum
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• v.3
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• pp.21-27
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• 2001

In National Central Museum, we recently preserved paper cultural assets, such as ancient maps, books and antique documents etc, to prepare "A Dynamic World of External Relations in Goryeo & Joseon Dynasty". The paper cultural assets generally react sensitively to their environments; temperature, humidity, light and physical force acting. Biological damages, which are caused by microbe, contraction, swelling and damage from insects occurred. Wrinkles on relics, which are made my physical force, stains on relics which are due to moisture, weakening of adhesive strength and damages from insects were found during the recent preservation handling. Therefore we are trying to find out any damage, which could be occurred in paper cultural assets and introduce brief emergency operation to prevent the damages and develop the preservation handling.

• Nuclear Engineering and Technology
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• v.54 no.1
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• pp.234-243
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• 2022

This study aims to characterize the irradiated RBMK-1500 nuclear graphite in terms of both structural and radiological properties. The experimental results of morphological and structural analysis of the irradiated graphite samples by using SEM, Raman spectroscopy as well as the theoretical evaluation of primary displacement damage are presented. Moreover, the experimental and theoretical evaluation of the neutron flux is provided and the presence of several γ emitters in the analyzed graphite samples is assessed. Furthermore, the improved version of rapid analysis method for ¹⁴C activity determination is applied and the experimentally obtained results are compared with calculated ones. Results indicate that structural changes are uniform enough in all the analyzed samples. However, the distribution of radionuclides is non-homogeneous in the irradiated RBMK-1500 reactor graphite matrix. The comprehensive understanding of both structural and radiological characteristics of nuclear graphite is very important when dealing with decision about irradiated graphite waste management strategy or treatment options prior to its final disposal.

• Journal of The Korean Society of Integrative Medicine
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• v.10 no.3
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• pp.73-84
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• 2022

Background : Lymphedema is a progressive disorder characterized by the impairment of lymph flow from tissues to the blood circulation system. This occurs as a result of damage to the lymphatic system. Complex decongestive therapy (CDT) is a multimodal, conservative therapeutic approach that is used for the management of lymphedema. CDT consists of a combination of compression therapy, manual lymphatic drainage, exercise, and skin care. Purpose : This study aimed to provide a review of available physical therapy interventions as well as general care guidelines for patients with lymphedema. Methods : The recommendations and guidelines for physical therapy management, medical management, and general information were reviewed from the following sources: 1) The American Physical Therapy Association, 2) The Norton School of Lymphatic Therapy, and 3) The International Society of Lymphology. This review contains general information, including the medical management and the importance of physical therapy in lymphedema. Physical therapy management should be based on an assessment of the patients' presenting impairments, including based on inclusion or exclusion of physical therapy interventions. This review also outlines a step-by-step approach that starts with disease diagnosis and progression all the way through to rehabilitation as an outpatient. Conclusion : Depending on the patients' journey to recovery and the requirement for rehabilitation, physical therapy interventions should focus on the patients' needs including pain, appearance, physical function and general rehabilitation. We hope that this review will provide information on evidence-based physical therapy and general care to patients with lymphedema.

• Journal of Life Science
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• v.21 no.7
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• pp.985-991
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• 2011

The purpose of this study was to investigate the biological effect of obesity-induced oxidative damage on neurogenesis and early protein expression. Obesity was induced I thirty 4-week old male Sprague-Dawley rats through a high fat diet for 15 weeks. After one week of environmental adaptation, the rats were divided into 2 groups: high fat diet sedentary group (HDS, n=15) and high fat diet training group (HDT, n=15). Exercise training was performed 5 times a week for 8 weeks, with mild-intensity treadmill running for weeks 1-4 and moderate-intensity treadmill running for weeks 5-8. After the 8 week training period, we analyzed lipid profiles, serum 8-hydroxyguanosine (8-OHdG), liver tissue malondialdehyde (MDA) related to oxidative damage factors, nerve growth factor (NGF), brain derived neurotrophic factor (BDNF), c-fos, c-jun, and extracellular signal regulated kinase (Erk) in the hippocampus. The results of this study are as follows. There were differences between HDS and HDT in triglyceride (TG) and total cholesterol (TC) (p<0.05). In high density lipoprotein (HDL-c), the HDT was higher than HDS after treadmill training (p<0.05). In 8-OHdG, the HDT was lower than HDS after treadmill training (p<0.05). Genetic expressions of c-jun, BDNF and MDA in the HDT were higher than in the HDS after treadmill training in hippocampus (p<0.05). Therefore, we conclude that 8 weeks of treadmill training can improve imbalanced lipid profiles, reduce oxidative damage, and activate neurogenesis in obese rats.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2004.11a
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• pp.131-135
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• 2004

The molecules of the substance absorbing a light obtains the radiant energy to the wavelength of the light to make thermal reactions or photochemical reactions. Specially, thermal reactions by infrared radiation brings about physical damage by temperature rise process or temperature drop process of the material. In this study, a measuring system was set up to measure the temperature rise and temperature drop of each sample by infrared radiation from light source. And a physical demage of samples by infrared radiation were measured using the measuring system.