• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제46권4호
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• pp.240-249
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• 2020

Objectives: Although the side effects of radiation therapy vary from mucositis to osteomyelitis depending on the dose of radiation therapy, to date, an experimental animal model has not yet been proposed. The aim of this study was to develop an animal model for assessing complications of irradiated bone, especially to quantify the dose of radiation needed to develop a rat model. Materials and Methods: Sixteen Sprague-Dawley rats aged seven weeks with a mean weight of 267.59 g were used. Atraumatic extraction of a right mandibular first molar was performed. At one week after the extraction, the rats were randomized into four groups and received a single dose of external radiation administered to the right lower jaw at a level of 14, 16, 18, or 20 Gy, respectively. Clinical alopecia with body weight changes were compared and bony volumetric analysis with micro-computed tomography (CT), histologic analysis with H&E were performed. Results: The progression of the skin alopecia was different depending on the irradiation dose. Micro-CT parameters including bone volume, bone volume/tissue volume, bone mineral density, and trabecular spaces, showed no significant differences. The progression of osteoradionecrosis (ORN) along with that of inflammation, fibrosis, and bone resorption, was found with increased osteoclast or fibrosis in the radiated group. As the radiation dose increases, osteoclast numbers begin to decrease and osteoclast tends to increase. Osteoclasts respond more sensitively to the radiation dose, and osteoblasts are degraded at doses above 18 Gy. Conclusion: A standardized animal model clinically comparable to ORN of the jaw is a valuable tool that can be used to examine the pathophysiology of the disease and trial any potential treatment modalities. We present a methodology for the use of an experimental rat model that incorporates a guideline regarding radiation dose.

• Journal of the Korean Society of Marine Environment & Safety
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• 제20권1호
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• pp.113-119
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• 2014

Recently, R.O.K. Navy is increasing re-usability of design data and application of M&S(Modeling and Simulation) through the establishment of collaborative product development environment focused on Naval Ship Product Model(NSPM). As a result, the reliability of the result of design is getting better, and furthermore, a study to improve quality of construction through simulation of production/operation is in progress. Accordingly, the database construction of design data and the DB(Database) quality become important, but there was not research related to those or it was just initial state. This paper conducted research about system of the quality verification process of shape elements which compose NSPM based on the quality verification guideline of NSPM as the result of the precedent study. The hull surface was limited as verification object. The study to verify two things that application of basic drawing by the cad model of hull surface, and whether there is error in the geometric quality of cad model was progressed. To achieve this goal, the verification criteria and algorithm were defined and the prototype system which is based on was developed.

• Journal of Conservation Science
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• 제7권1호
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• pp.9-18
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• 1998

There are about 1470 stone-cultural properties in Korea which have been registered and protected by the government. Representative of them are pagoda, stupa, stone-buddha, stele support of banner pole and stone-lanterns. Most of them have been exposed to and weathered by natural environments. Stone-cultural properties are destroyed and/or destructed mostly by weathering and its related features of rocks. Therefore, it is necessary to conduct geological studies on the weathering phenomena and related features as well as characteristics of the rock itself must be done for the conservation. Thus geological investigation should include detail measurements, rock varieties and phases, structural lineaments of the rock, cause and degree of weathering, degree and patterns of crack development structural stability, identification of reusable parts for restoration, geomorphological characteristics of the site, and etc. The interaction among these factors must be investigated and analyzed, which must be used as basic data to establish the guideline of conservation and to plan for repair and/or restoration. The conservation plan should involve parts to be repaired, method of repair, type of cementing material, the characteristics of rock phases to be supplemented, method for maintaining structural stability, and method to delay or to prevent the rock weathering.

• Journal of the Korean Association of Geographic Information Studies
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• 제15권1호
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• pp.52-63
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• 2012

This study empirically investigated some problems with the criteria for subdividing the management zone in a rural area through a case study of Cheongsong-gun, Gyeongbuk and provided some suggestions for their improvement. To do this, the subdivision criteria in the guideline for developing urban management planning were firstly compared with those of Cheongsong-gun. Next, geographic information system(GIS) was used to do the cross-check analysis between the results from land suitability assessment and those from the subdivision in the management zone and to grasp the spatial relationships of a zone with its neighboring zones by analyzing the zoning inventory and comparing the areas. Finally, map analysis and field survey were conducted to examine the relevance to the actual situation of land use and focus interviews were done to analyze the civil complaint cases resulted from the subdivision in the management zone. This study found out three major categories of problems with the criteria for subdividing the management zone in Cheongsong-gun: the incomplete formalization of zoning, the inadequate decision criteria on the availability of land for development, and the biased consulting of the departments concerned. Some suggestions for their improvement were then provided in this study. The empirical results from this study can be used as the preliminary information for suggesting the right direction of the subdivision in the management zone within the rural areas in the near future.

• Journal of the Korean Recycled Construction Resources Institute
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• 제4권4호
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• pp.379-387
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• 2016

In this study, a survey was conducted on the required measurement and waterproofing performance for residential building underground structure leakage prevention system. According to the results of the survey, it has been determined that leakage problem is considered to be quite severe, and many respondents have agreed. The legal guidelines and regulation systems do not reflect properly on the environmental requirements or conditions, resulting in continued leakage problem. In regards to this, a standardized waterproofing technique that can be used in underground areas of residential structures is required as an obligation and the development of high performance waterproofing method that allows for wet concrete surface adhesion and a guideline, design and maintenance method that allows the control of overall situational control of leakage is required.

• Journal of the Korean GEO-environmental Society
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• 제10권1호
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• pp.49-54
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• 2009

The seismic slope stability is most often evaluated by the pseudo-static limit analysis, in which the earthquake loading is simplified as static inertial loads acting in horizontal and/or vertical directions. The transient loading is represented by constant acceleration via the pseudostatic coefficients. The result of a pseudostatic analysis is governed by the selection of the value of the pseudostatic coefficient. However, selection of the value is very difficult and often done in an ad hoc manner without a sound physical reasoning. In addition, the maximum acceleration is commonly estimated from the design guideline, which cannot accurately estimate the dynamic response of a slope. There is a need to perform a 2D dynamic analysis to properly define the dynamic response characteristics. This paper develops a new hybrid pseudostatic method that links the modified one-dimensional seismic site response analysis and the pseudostatic algorithm. The modified site response analysis adjusts the density of the layers to simulate the change in mass and weight of the layers of the slope with depth. Multiple analyses were performed at various locations within the slope to estimate the change in seismic response of the slope. The calculated peak acceleration profiles with depth from the developed procedure were compared to those by the two-dimensional analyses. Comparisons show that the two methods result in remarkable match. The calculated profiles are used to perform pseudostatic analysis. The results show that use of peak or a fraction of acceleration at the surface can seriously underestimate or overestimate the factor of safety, and that the proposed procedure significantly enhances the reliability of a standard procedure.

• Korean Journal of Social Welfare
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• 제56권2호
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• pp.215-235
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• 2004

A little understood but rapidly growing phenomenon in our society is remarriage. By 2002, 21% of marriage involved the remarriage of one or both partners. Furthermore, the ratio of remarriage of women has outnumbered the ratio of remarriage of men, which is remarkable change compared to the traditional culture putting a taboo on women's remarriage in Korea. The purpose of this study is to construct the perspective and the direction of programs for enhancing the remarriage family functioning. For the purpose, we explore the intrinsic vulnerability to family dissolution of remarriage and ill preparation for remarriage of people. There are unrealistic myths around, lack of informations on, absence of guideline for remarriage family life. Also, we discuss the process of remarriage family development, which leads us to the conclusion that the remarriage shows totally different family structure and family interaction from first marriage nuclear family. Based on discussion mentioned above, several suggestions are provided for developing programs for remarriage family functioning. Above all, the family developmental perspective on remarriage is more useful paradigm rather than deficit-comparison perspective for remarriage family. Also, the programs for remarriage family functioning should challenge the unrealistic myths around remarriage such as the instant love between step-parents and step-children, the re-created nuclear family, etc. Also, several points such as the remarried family developmental stage, the disparity in expectation of man and woman on remarriage, and the tendency to scapegoat a stepmother should be considered in programs for enhancing remarriage family functioning.

• Journal of the Korean Institute of Gas
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• 제21권6호
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• pp.88-95
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• 2017

The usage of toxic gas in Korea is increasing in the development of high-tech industries such as semiconductors, displays and solar panels. The recent survey of domestic toxic gas consumption indicates an increase in annual average of 12.4 percent, but it is still focused on usage, and it is negligent in safety and treating the post. In September 2012, an accident occurred in Gu-mi involving hydrofluoric acid leak demonstrates the absence of safety management. Due to the incident, the government, industry and academia have been interested in chemical substances(toxic gas), and the government-led safety management has been established and implemented, but there are still a lot of safety blind spots. The purpose of this study is to develop effective measurement methods for the destruction or removal efficiency of gaseous materials emitted from the Scrubber used in the semiconductor and display industries. Also, this study demonstrated how toxic gas facilities can be applied without error by verification test for the measurement method guideline of the destruction or removal efficiency of the green-house gas reduction facility in the semiconductor and display industries used by the National Institute of Environmental Research and the UNFCCC, and suggested the differentiated measurement methods for toxic gas reduction facilities, and the third party certification for safety facilities is needed to prevent toxic gas accidents.

• Journal of the Ergonomics Society of Korea
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• 제34권1호
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• pp.29-43
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• 2015

Objective: The aim of this study is to develop management guidelines and a procedure for an anthropometric suitability assessment of the main control room (MCR) in nuclear power plants (NPPs). Background: The condition of the MCR should be suitable for the work crews in NPPs. The suitability of the MCR depends closely on the anthropometric dimensions and ergonomic factors of the users. In particular, the MCR workspace design in NPPs is important due to the close relationship with operating crews and their work failures. Many documents and criteria have recommended that anthropometry dimensions and their studies are one of the foremost processes of the MCR design in NPPs. If these factors are not properly considered, users can feel burdened about their work and the human errors that might occur. Method: The procedure for the anthropometric suitability assessment consists of 5 phases: 1) selection of the anthropometric suitability evaluation dimensions, 2) establishment of a measurement method according to the evaluation dimensions, 3) establishment of criteria for suitability evaluation dimensions, 4) establishment of rating scale and improvement methods according to the evaluation dimensions, and 5) assessment of the final grade for evaluation dimensions. The management guidelines for an anthropometric suitability assessment were completed using 10 factors: 1) director, 2) subject, 3) evaluation period, 4) measurement method and criteria, 5) selection of equipment, 6) measurement and evaluation, 7) suitability evaluation, 8) data sharing, 9) data storage, and 10) management according to the suitability grade. Results: We propose a set of 17 anthropometric dimensions for the size, cognition/perception action/behavior, and their relationships with human errors regarding the MCR design variables through a case study. The 17 selected dimensions are height, sitting height, eye height from floor, eye height above seat, arm length, functional reach, extended functional reach, radius reach, visual field, peripheral perception, hyperopia/myopia/astigmatism, color blindness, auditory acuity, finger dexterity, hand function, body angle, and manual muscle test. We proposed criteria on these 17 anthropometric dimensions for a suitability evaluation and suggested an improvement method according to the evaluation dimensions. Conclusion: The results of this study can improve the human performance of the crew in an MCR. These management guidelines and a procedure for an anthropometric suitability assessment will be able to prevent human errors due to inadequate anthropometric dimensions. Application: The proposed set of anthropometric dimensions can be integrated into a managerial index for the anthropometric suitability of the operating crews for more careful countermeasures to human errors in NPPs.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제22권4호
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• pp.271-286
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• 2011

Objectives : The purposes of this study were to develop a mental health screening questionnaire and the practical intervention programs or guidelines which can be used in middle and high schools by students and teachers. Methods : The Adolescent Mental health & Problem behavior Screening Questionnaire II (AMPQ-II) was developed and was tested for reliability and validity using nationwide data from 2,180 middle and high school students and 2,145 teachers. Results : The AMPQ-II was measured by both students and teachers. The correlation coefficient of the test-retest test was 0.567 and internal consistency was high (Cronbach's alpha=0.878). Five factors such as worry and thought, mood and suicide, academic and Internet-related problems, peer problems, and rule violations were proposed. We also developed a practical guideline and manuals which can be easily used by secondary school teachers to screen for and manage mental health problems at school. Conclusion : The AMPQ-II can be a useful and reliable tool to screen for mental health problems in middle and high schools in South Korea.