• 한국태양에너지학회:학술대회논문집
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• 2009.11a
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• pp.32-37
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• 2009

An energy loss through the window system occupies about 10 to 30 percent on energy consumption of the whole building. That is the reason, several elements for a building composition of window system are the weakest from the heat. Insulation performance increases for the reducing heat loss. Heat transfer through the window system that is reducing heat transfer through conduction, convection and radiation. Insulation performance reinforcement methods classify improving heat specific quality of window system and improving efficiency of whole window system. The most application method among each methods is reducing emission ratio of the window system(Low-E glass), increasing a number of glazing(multiple window) and a method of vacuuming between glazing and glazing. Therefore this study is investigated a sort of glazing and specific character, U-value calculation with changing glazing thickness and calculation of temperature distribution and U-value with a glazing charging gas kind from double glazing. For a conclusion, an aspect of U-value figure at the smallest value case of vacuum glazing with Low-E coating. That means insulation efficiency is the best advantage during a building plan selecting vacuum glazing with Low-E coating for a energy saving aspect. In this way, U-value become different the number of glazing, coating whether or not and selecting injection gas. Therefore selecting of glazing is very important after due consideration by a characteristic and use of building and consideration of strong point and weak point.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.8 no.4
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• pp.110-121
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• 2009

It is essential to embed product quality in the design process to win the global competition. Many components found in many products including automobiles and electronic devices are fabricated using sheet metal forming processes. Wrinkle and fracture are two types of defects frequently found in the sheet metal forming process. Reducing such defects is a hard problem as they are affected by many uncontrollable factors. Attempts to solve the problem based on traditional deterministic optimization theories are often led to failures. Furthermore, the wrinkle and fracture are conflicting defects in such a way that reducing one defect leads to increasing the other. Hence, it is a difficult task to reduce both of them at the same time. In this research, a new design method for reducing the rates of conflicting defects under uncontrollable factors is presented by using operating window and a sequential search procedure. A new SN ratio is proposed to overcome the problems of a traditional SN ratio used in the operating window technique. The method is applied to optimizing the robust design of a sheet metal forming process. To show the effectiveness of the proposed method, a comparison is made between the traditional and the proposed methods using simulation software, applied to a design of particular sheet metal forming process problem. The results show that the proposed method always gives a more robust design that is less sensitive to noises than the traditional method.

• Korean Journal of Agricultural Science
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• v.47 no.4
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• pp.1083-1096
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• 2020

Global attention to the greenhouse gas emissions from deforestation and forest degradation is increasing. There is a growing recognition of reducing emission from deforestation and forest degradation plus (REDD+) as an effective way to reduce greenhouse gas emissions in the forestry sector. The Republic of Korea is implementing REDD+ pilot projects in four Southeast Asian countries as part of its efforts to reduce greenhouse gas emissions. This study evaluates countries with the potential to become priority partner countries for Korea's REDD+ programs, using the following five criteria: The first criterion is that a country should include the forest sector and REDD+ in its national plan for reducing greenhouse gas (GHG) emissions. The second and third criteria refer to an average forest coverage rate of over 44% and a forest change rate of over - 0.1%, among the countries with forest cover of more than 10 million ha. The fourth criterion is that the country should meet the Forest Reference Emission Level requirements, one of the four elements of the Warsaw REDD+ Framework. The fifth criterion is that the country should have bilateral relations with the Republic of Korea in forestry while at the same time be a partner country for cooperation on climate change as well as a REDD+ pilot country. Based on our evaluation, we conclude that the first priority countries are Indonesia, Cambodia, and Myanmar. The second priority countries include Brazil, Ecuador, and Peru. Finally, the third priority countries are Columbia, Congo, and Mozambique. This study suggests that for the selection of priority partner countries, Korean REDD+ programs should center on existing REDD+ pilot countries.

• International Journal of Human Ecology
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• v.8 no.1
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• pp.109-116
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• 2007

Leisure time is a critical part of modern life and is increasingly important in modern society. Therefore, analyzing expectations and values of leisure and researching leisure practices are integral in measuring the quality of life. In this respect, differences between values and attitudes leading to the ideal leisure life and the actual leisure life could provoke negative influence on our lives, further, decreasing quality of life. Therefore, classifying leisure lifestyle through analyzing value of lifestyle and the actual state of leisure precisely is very necessary. Leisure lifestyle could be very useful standard satisfying various desires and demands related to leisure. In the research, we surveyed 3,000 people over 10 years of age, one on one interview method, asking value of life behaviors (Individualism vs. Collectivism, Pro-Stability vs. Pro-Change, Statistical way of life vs. Active way of life, Family-centered life vs. Work-centered life) and practices of leisure life (With whom, How frequently, Where, For what) in respect to both value and behaviors. Through this survey, five groups of leisure life type have been identified; "Community-oriented Type", "Cocoon Type", "Family-oriented Type", "Personal-stability Type" and "Multiplicity Type". These leisure lifestyles would provide effectual alternatives for reducing gaps between expectations for ideal leisure life and actual life. Furthermore, this could be used for ground work to develop measurements for satisfying various leisure demands.

• Journal of Power System Engineering
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• v.22 no.1
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• pp.72-78
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• 2018

With growing concerns over air pollutions attributed to shipping activities, the international maritime organization has enacted a series of stringent regulations. In particular, MARPOL Annex IV Reg. 16 requires sulfur contents from exhaust gases of marine engines to be progressively reduced. To comply with this regulation, three feasible options have been introduced: using LNG as a marine fuel, using heavy fuel oil with the scrubber system, and using the marine gas oil (a type of low sulfur fuel oil). For the objectives of this paper, the holistic environmental impacts pertinent to these options were investigated and compared in ways that the flows of energy and emission were tracked and quantified through the life cycle of the ship. Research findings obtained from a case study with a large bulk carrier showed that the use of the scrubber system to purify heavy fuel oil would produce relatively fewer amounts of emissions attributing to global warming than other two options. On the other than, the use of LNG would be the way to operate the ship in a cleaner way in terms of reducing the acidification, eutrophication, and photochemical effects. Throughout the analysis, the excellence of life cycle assessment was proven to shift the environmental impact of marine systems from the short-term view to the long-term one.

• Journal of Institute of Control, Robotics and Systems
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• v.13 no.10
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• pp.990-999
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• 2007

We deal with second order NMP(Non-Minimum Phase) systems which are difficult to control with conventional methods because of their inherent characteristics of undershoot. In such systems, reducing the undesirable undershoot phenomenon makes the response time of the systems much longer. Moreover, it is impossible to control the magnitude of undershoot in a direct way and to predict the response time. In this paper, we propose a novel two sliding mode control scheme which is capable of determining the magnitude of undershoot and thus the response time of NMP systems a priori. To do this, we introduce two sliding lines which are in charge of control in turn. One is used to stabilize the system and achieve asymptotic regulation eventually like the conventional sliding mode methods and the other to stably control the magnitude of undershoot from the beginning of control until the state meets the first sliding line. This control scheme will be proved to have an asymptotic regulation property. The computer simulation shows that the proposed control scheme is very effective and suitable for controlling the second order NMP system because it can decide the magnitude of undershoot in a direct and stable way and reduce the response time compared with the conventional ones.

• Industrial Engineering and Management Systems
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• v.11 no.3
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• pp.276-287
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• 2012

Determining storage locations of containers is an important issue for efficient operation of container terminals. This study assumes a storage yard with a horizontal layout in which blocks are laid out in parallel to the quay and trucks enter at the side of a block to deliver (receive) a container to (from) the yard crane. Various storage rules for determining storage locations of containers are introduced. Simulation studies are conducted for evaluating various rules. The following guidelines are derived from the result of our simulation study: when designing a block, consider a block configuration in which the longest gantry and the longest trolley travel times of rail-mounted gantry cranes (RMGCs) are similar; do not restrict the types of containers that can be stored in a storage area; if different roles are to be assigned to different storage areas, one possible way is to divide a bay into two areas so that some rows in the bay are allocated to inbound containers while the other rows in the same bay are allocated to outbound containers; reserve the space in bay unit for a high productivity of RMGCs but reserve the space in stack unit when the storage space is not enough; when the storage space is not sufficient, allocate storage location in a way of starting from the end and ending at the middle of a block; for reducing the travel distance of internal trucks, provide a higher priority to a block nearer to the berthing position of the corresponding vessel.

• Journal of Home Health Care Nursing
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• v.30 no.2
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• pp.202-215
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• 2023

Purpose: This study attempted to determine the factors related to behaviors of reducing exposure to endocrine disrupting chemicals (BRE to EDCs) in pregnancy, based on the PRECEDE model. Methods: A cross-sectional survey was conducted with participants (N=239) who met the medical records and eligibility criteria from the Women's Hospital and Public Health Center. Data were collected using a specially-designed questionnaire based on the PRECEDE model and included BRE to EDCs predisposing factors, reinforcing factors, and enabling factors. The data were analyzed using the chi-square test, independent t-test, one way ANOVA, Pearson's correlation coefficients and a hierarchical multiple regression analysis. Results: In Model I it was found that participation in prenatal education influenced the BRE to EDCs significantly; and a regression showed that the determinant variables accounted for 3.4%. In Model II, the predisposing factors of perceived barriers of BRE to EDCs and environmental self-efficacy were added. It was shown that they significantly influenced BRE to EDCs in the order named, and a regression revealed that increases in the determinant variables accounted for 22.5%. In Model III, to which enabling factors were added, the information acquisition experience of BRE to EDCs interacted significantly with BRE to EDCs and a regression showed an increase in the determinant variables accounting for 25.3%. Conclusion: The results of this study, the content of endocrine disruptors must be included in the prenatal care education program for pregnant women, and it should be composed of contents that can reduce the perceived obstacle to BRE to EDCs, enhance the environmental self-efficacy, and provide the information in regard to reducing exposure to EDCs.

• Environmental Engineering Research
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• v.22 no.4
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• pp.432-438
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• 2017

Slum settlement, a direct result of the rapid worldwide urbanization is a common site in most developing countries. Uganda is among the top African countries with high number of slums. The status of Katanga slum located in the low-lands between Mulago national hospital and Makerere University is a typical of many other slums within Uganda. This project proposal seeks to tackle urbanization challenges by specializing in slum upgrading as a sustainable way of curbing the menace. An integrated toilet, biogas, poultry and backyard gardening project is proposed as a channel of boosting the Katanga slum dwellers' economic, sanitation and domestic energy status. Designed to serve up to 30 households, the project will utilize residual wastes from poultry houses and toilets to produce biogas and slurry. The biogas yield will provide clean cooking fuel and energy for lighting, while the slurry used as organic fertilizers to improve vegetable yields. The social, economic and environmental impacts of the project will empower the vulnerable women and children within the slums and reduce water pollution and land degradation. This affordable project can be applied in developing countries experiencing slum settlement challenges as a strategy for reducing urbanization pressure.

• 한국IT서비스학회:학술대회논문집
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• 2003.11a
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• pp.233-240
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• 2003

To develop high-quality software systems satisfying the customer's needs, user-centered design (UCD) process has been emphasized in the area of human-computer interaction. And component-based development (CBD) has been extensively studied to realize a systematic software reuse, thereby reducing the time-to-market and the development cost. Balanced integration of user-centered design process and CBD process will be a promising way for successful software construction, which effectively achieves three goals: the quality of software, the cost of software development, and the time-to-market. However, traditional CBD methodology seems to lack the concept of user-centered design process and the relevant methods. This paper proposes a way of incorporating user-centered design process into a CBD methodology. Firstly, this paper gives the brief introduction of UCD. Secondly, we explain typical UCD activities and methods along the phase of systems development lifecycle and propose the use of usability maturity model (UMM) for integrating UCD activities and methods with those of CBD methodology. Finally, as a case study, we describe the results of comparing the UCD activities to the activities of MaRMI-III, which has been developed as a CBD methodology at ETRI.