• Journal of Power Electronics
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• v.14 no.4
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• pp.649-660
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• 2014

A novel non-isolated bidirectional soft-switching SEPIC/ZETA converter with reduced ripple currents is proposed and characterized in this study. Two auxiliary switches and an inductor are added to the original bidirectional SEPIC/ZETA components to form a new direct power delivery path between input and output. The proposed converter can be operated in the forward SEPIC and reverse ZETA modes with reduced ripple currents and increased voltage gains attributed to the optimized selection of duty ratios. All switches in the proposed converter can be operated at zero-current-switching turn-on and/or turn-off through soft current commutation. Therefore, the switching and conduction losses of the proposed converter are considerably reduced compared with those of conventional bidirectional SEPIC/ZETA converters. The operation principles and characteristics of the proposed converter are analyzed in detail and verified by the simulation and experimental results.

• Proceedings of the KIEE Conference
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• 2004.11a
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• pp.223-226
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• 2004

Many extensive researches in the area of sensor's technology for corrosion monitoring in concrete structures have increasingly been carried out in recent years. This paper gives a brief discussion on the principles and usage of the role of sensors involved in both corrosion initiation and propagation steps of reinforcement corrosion monitoring in concrete structures. Special attention was given to the review of various sensing devices, selection of reliable sensing devices for detecting reinforcement corrosion at the particular environment and at the efficiency of the devices used. Various sensing operations in new and existing concrete structures are also described.

• 중국학논총
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• no.70
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• pp.87-108
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• 2021

This paper makes a comparative analysis of and (Third Edition) textbook. In the introduction part, it puts forward the purpose, significance and research object of the text, combs the general situation of the research on the arrangement of business Chinese textbook, discusses the concept and characteristics of business Chinese, and then makes a detailed comparative analysis of and Two Business Textbooks for Korean and Chinese. Firstly, the paper compares the compiling principles, compiling purposes and applicable objects. Then, it compares the text content, vocabulary selection, grammar teaching, culture and other aspects. Business Chinese has more international teaching ideas and diversified teaching methods in textbook editing, while the former is more targeted in different countries, reflecting more contents of cultural comparison between China and Korea in textbook content. we hope to find a reasonable plan for the compilation of Korean business Chinese textbooks.

• Journal of the Korean Society of Radiology
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• v.84 no.5
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• pp.985-998
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• 2023

Radiofrequency ablation (RFA) has been a representative, non-surgical treatment for benign thyroid nodules that cause cosmetic problems or compression symptoms. The procedure of RFA should be performed effectively and safely. This review discusses the patient selection, pre-procedure evaluation and planning, principles, devices, techniques, and complications with reference to the guidelines and research on thyroid RFA. In particular, this review will devote to introduce RFA techniques and to provide practical help in the implementation of this procedure.

• Journal of Pharmacopuncture
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• v.21 no.3
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• pp.203-206
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• 2018

Objectives: There is an increasing number of complex diseases that are progressively more difficult to be controlled using the conventional "single compound, single target" approach as demonstrated in our current modern drug development. TCM might be the new cornerstone of treatment alternative when the current treatment option is no longer as effective or that we have exhausted it as an option. Orthogonal stimulus-response compatibility group study is one of the most frequently employed formulas to produce optimal herbal combination for treatment of multi-syndromic diseases. This approach could solve the relatively low efficacy single drug therapy usage and chronic adverse effects caused by long terms administration of drugs that has been reported in the field of pharmacology and medicine Methods: The present review was based on the Science Direct database search for those related to the TCM and the development of antihypertensive TCM herbal combination using orthogonal stimulus-response compatibility group studies approach. Results: Recent studies have demonstrated that the orthogonal stimulus-response compatibility group study approach was most frequently used to formulate TCM herbal combination based on the TCM principles upon the selection of herbs, and the resulting formulated TCM formula exhibited desired outcomes in treating one of global concerned complex multi-syndromic diseases, the hypertension. These promising therapeutic effects were claimed to have been attributed by the holistic signaling mechanism pathways employed by the crude combination of herbs. Conclusion: The present review could serve as a guide and prove the feasibility of TCM principles to be used for future pharmacological drug research development.

• Korean Journal of Community Nutrition
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• v.3 no.4
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• pp.655-667
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• 1998

The Computer-assisted Hazard Analysis and Critical Control Point(HACCP) program has been developed for a systematic implementation of HACCP principles in identifying, assessing and controlling hazards in institutional foodservics operations. The HACCP-based sanitation evaluation tool has been developed, based on the results of the computerized assisted HACCP program in 4 service sites of C contracted foodservice company, including 2 general hospitals with 650-beds, one office operation of 400 meals per day, and one factory foodservice of 1,000 meals per day. All database files and processing programs were created by using Unify Vision tool with Windows 95 of user environments. The results of this study can be summarized as follows : 1. This program consists of the pre-stage for HACCP study and the implementation stage of the HACCP system. 1) The pre-stage for HACCP study includes the selection of menu items, the development of the HACCP recipe, the construction of product flow diagrams, and printing the HACCP recipes and product flow diagrams. 2) The implementation of the HACCP system includes the identification of microbiological hazards, the determination of critical control points based on the decision tree base files. 3) The HACCP-based sanitation evaluation tool consisted of 3 dimensions of time-temperature relationship, personal hygiene, and equipment-facility sanitation. The Cronbach's alphas calculation indicated that the tool was reliable. The results showed that the focus groups rated the mean of importance in time-temperature relationship, personal hygiene, and equipment-facility sanitation as 4.57, 4.59 and 4.55 respectively. Based on the results, this HACCP-based sanitation evaluation tool was considered as an effective tool for assuring product quality. This program will assist foodservice managers to encourage a standardized approach in the HACCP study and to maintain a systematic approach for ensuring that the HACCP principles are applied correctly.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.6
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• pp.40-49
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• 2017

The purpose of the research is to analyze the recent cases of green space planning and planting design in Beijing, one of the cities having the worst particulate matters (PM) pollution. This study comprehensively reviewed Chinese academic literature addressing green space planning to reduce PM pollution. In addition, we conducted field observations and interviews with public officials from Beijing Municipal Bureau of Landscape Design in charge of planning and management of green spaces in Beijing. After the extensive review of literature we derived tree planting principles to mitigate the impact of PM from urban road system, residential area, and industrial district. Using the principles we evaluated the three recent cases of planting design to mitigate PM: Beijing Fuxing Road, Fu Run Residential Area and Beijing Beiqi Multipurpose Vehicle Factory. We conclude that green space planning and trees planting are not effective in mitigating negative impact of PM pollution because of inadequate selection of trees and inconsiderate planting composition. We proposed to replace the tree species with the ones capable of reducing the spread of PM, and reorganize planting compositions that consider the directions and characteristics of urban wind flow. This study suggests desirable types of tree species and planting compositions for road, residential and industrial districts, and we expect that it provides helpful guidelines for making planting design and species selection to mitigate the impact of PM in urban landscape.

• Korean Journal of Heritage: History & Science
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• v.45 no.1
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• pp.174-189
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• 2012

This study aims to examine the traditional living space to reflect the environment-friendly design methods and principles of reestablishment. To do so, this study carried on a related literature study and field survey. The traditional living space in terms of the environmental friendliness is reflected on site selection and space composition, and utilization of natural energy and natural materials. Focused on the Kwangajeong in Yangdong Village, this study is to identify eco-friendly techniques on the traditional living space. As a result, it shows that Kwangajeong with the side of the southeast in site selection had been considered in aspect of environmental control such as sunshine and solar radiation. Also building construction techniques had been used to minimize the variation of terrain. In aspect of environmental conservation, Kwangajeong had structurally arranged the gate, an inner yard and an inner floor to allow good ventilation. In aspect of space composition, Kwangajeong with the emphasis of scenic view had utilized the methods that attract external landscape through the control of its fences. Environment-friendly techniques and control principles in traditional space had been developed by a long experience through the long periods and the traditional techniques suitable for local climate and local environment have been developed. The technical development of these techniques to resolve the global environmental and energy issues and create a more pleasant living environment of human beings might be critical.

• Korean Journal of Heritage: History & Science
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• v.44 no.3
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• pp.164-177
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• 2011

This study aims to examine the traditional living space to reflect the environment-friendly design methods and principles of reestablishment. To do so, this study carried on a related literature study and field survey. The traditional living space in terms of the environmental friendliness is reflected on site selection and space composition, and utilization of natural energy and natural materials. Focused on the Kwangajeong in Yangdong Village, this study is to identify eco-friendly techniques on the traditional living space. As a result, it shows that Kwangajeong with the side of the southeast in site selection had been considered in aspect of environmental control such as sunshine and solar radiation. Also building construction techniques had been used to minimize the variation of terrain. In aspect of environmental conservation, Kwangajeong had structurally arranged the gate, an inner yard and an inner floor to allow good ventilation. In aspect of space composition, Kwangajeong with the emphasis of scenic view had utilized the methods that attract external landscape through the control of its fences. Environment-friendly techniques and control principles in traditional space had been developed by a long experience through the long periods and the traditional techniques suitable for local climate and local environment have been developed. The technical development of these techniques to resolve the global environmental and energy issues and create a more pleasant living environment of human beings might be critical.

• Journal of Nutrition and Health
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• v.42 no.2
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• pp.183-188
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• 2009

There has been a need to update the current Codex nutrient reference values (NRVs) which had been established following the Helsinki Consultation in 1988. The main purposes of NRVs are to help consumers compare the nutrient content of different food products and estimate the usefulness of a food product in terms of its percentage contribution to the overall healthful diets. The establishment of Codex NRVs for labelling purposes is intended to facilitate the goals of protecting consumers' health and ensuring fair practices in food trade. When revising the Codex NRVs several issues are needed to discussed, which are: 1) Consideration of population groups whether to have one set of NRVs for general population or to have several sets of NRVs for each population groups, 2) Determination of scope of nutrients such as what nutrients to include and what reference values to choose and 3) Development of principles for establishing NRVs such as the selection of suitable reference values among many including recommended intake/recommended dietary allowances, estimated average requirement and upper levels to extract NRVs. This paper will discuss the above issues and the inputs and efforts that the Korean Nutrition Society had put into to carry out the project, "International Collaboration on the Revision and Addition of the Codex Nutrient Reference Values for Food Labelling Purposes," and to ascertain relevant scientific principles and evidences that are utilized for establishment and revision of the Codex NRVs.