• Proceedings of the KSME Conference
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• 2007.05b
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• pp.3335-3340
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• 2007

The government have been tightening EM regulation gradually but the effect is not good because of rapid increase of vehicles. And medium & heavy duty diesel vehicles, even though the number is small, exhaust very large pollutants(about over 50%). Especially it is more severe about old trucks and buses. Accordingly, CNG vehicle and the retrofit of diesel to CNG must be an alternative in order to protect the atmospheric environment and improve the air quality in the metropolitan area. The main object of this study is to secure the retrofit technology of diesel to CNG vehicle and the management system of CNG engine. we passed the government emission certification test. In addition to this, the mass production for retrofit is also studied. Results of emission and durability test for certification are as follows; there was no problem during 30,000km vehicle durability test and good emission levels satisfying the regulation.

• Journal of Korea Multimedia Society
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• v.5 no.6
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• pp.638-645
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• 2002

One of the potential advantages of computer-based instruction is individualization of instruction. However, this goal has not been fully realized in practice, due largely to limitations of natural language understanding and to combinatorial explosion. It is nonetheless possible to develop CAT(Computer- based Adaptive Testing) Programs which can adapt to students, depending on their performance, by adjusting the length of computer-based tests. The number of questions can be significantly reduced for many individuals, while mastery and nonmastery decisions remain highly accurate. In this paper, We design and implement a Diagnosis System using SPRT(Sequential Probability Ratio Testing). This system supports multimedia object, client/server environment, indvidual feedback, multi-SPRT and maintain student model for individualization of instruction. besides, this system measures coefficient alpha of each problem.

• Journal of the Korean Institute of Rural Architecture
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• v.12 no.1
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• pp.49-56
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• 2010

This paper is aimed to clarify field technique of non-educated constructors in timber structure of korean-style secondary station(Gong-So) on the annex of catholic church. The main object of this study is Sin-Sung and Su-Bun secondary stations which post-lintel structure was 2high columns(Go-Ju) 5beams(Ryang) in Jeon-Buk area of Korea. We reached the following conclusion. Firstly, these secondary stations are required a lots of space for number of persons with the introduction of basilica plane. These plans have different intervals in the layout. Secondly, they constructed the holy space by using high columns(Nae-Jin-Go-Ju). The former problems of plan layout are sloved by reinforcement and replacement eaves and rafter of logitudinal. Thirdly, the elements showed the natural feature such as irregular wooden floor, arch-type head pentrating tie and a ceiling. In the end, we knew that non-educated constructor had found a way in the problem for accepting unreasonable work.

• Journal of Korean Society of Rural Planning
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• v.25 no.4
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• pp.129-149
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• 2019

This study is to give a three-dimensional view of the concept of rurality and ruralness in terms of time-span, perceived object and awareness level. In the precedent studies ruralness or rurality has been approached as the category of usefulness resources called amenity. This overlooked the perceived representation, institutional reference and rurality of ideological values. Rurality appears as a cumulative representation of being rural from the past to the present, but ruralness exists as a desirable form or value for the future. Through this study, it has been analyzed that ruralness consists of six realms such as environment, community, self-reliance, aesthetics, enjoyable amenity and settlement, and of three or four sub-realms by each amounting to 20 in total. According to the vocabulary listing by the survey to 30 experts, rurality for the past-present is mainly imagined as of natural environment, agriculture, landscape, and community history, while ruralness for the future is frequently described as of communities, settlement and self-reliance by number of references. Through the vocabulary extraction, 17 words in the level of mid-conception are induced including ecology, comfort, history, agriculture, landscape, place, culture, convenience, etc. In conclusion the concept of ruralness along with rurality could be organized into three different layers of perception consisting of representation, norms and usefulness.

• Bulletin of the Society of Naval Architects of Korea
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• v.14 no.1
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• pp.1-10
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• 1977

The major objects of this report are to supplement data of natural frequencies of thin elastic rectangular plates to the available data, and to give an experimental verification for natural frequencies obtained by Rayleigh-Ritz method, the generation set of which are eigenfunctions of Euler beams. For the first object the following five models, for which data only for the fundamental mode or data only for square plates are available, are adopted; (1) two opposed edges are clamped and the other two opposed edges simply supported (C-C, S-S), (2) one edge is simply supported and the other three edges clamped (C-C, C-S), (3) one edge is free and the other three edges clamped (C-C, C-F), (4) two adjacent edges are clamped and the other two adjacent edges free (C-F, C-F). For the (C-C, S-S) model the frequency equation obtained with the mode shapes assumed as of a single trigonometric series is solved. And for the other four models Rayleigh-Ritz method taking eigenfunctions of Euler beams as the generating set is applied. The numerical examples are obtained up to the fourth, the fifth or the sixth order depending on the range of the aspect ratio (0.1-10.0). The number of terms in the generating set for Rayleigh-Ritz method is fifteen for all models. For the experiment three models made of 3.2mm thickness mild steel plate for general structure use were prepared in following size; $300mm{\times}600mm,\;600mm{\times}600mm\;and\;900mm{\times}600mm$. Their boundary conditions are made to fit (C-C, C-F) condition. From the experiment mechanical impedance curves based on the frequency response method were obtained together with phase relation diagrams. The experimental data are resulted in good conformity to calculated values.

• Korean Journal of Agricultural Science
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• v.44 no.1
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• pp.123-132
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• 2017

Nowadays, many people suffer from stress because of their jobs, studies, traffic, etc. Daily stress may cause many diseases (Garrett, 1991). One of the methods for reducing stress is experiencing a natural environment (Frumkin, 2001). Cibodas botanical garden (CBG) is one of the most famous travel destinations in Bogor, Indonesia. CBG has the potential for tourism activities. However, an economic assessment is required to verify their sustainability. The research objectives of this study were to identify the characteristics of tourism utilization in CBG, to analyze the economic tourism value of CBG, and to measure the effectiveness of traveling to a natural environment for reducing stress. The research method used was the survey. This study used three data analysis methods: (1) descriptive analysis which was used to identify the characteristics of tourists, (2) travel cost method (TCM), and (3) contingent valuation method (CVM). Results showed some differences in the characteristics of foreign and domestic tourists respondents in age, educational background, income level, number of dependents, and the frequency of their visits. CBG has a high economic value, amounting to IDR (Indonesian Rupiah) 5,508,932,605,405 or approximately USD (United State Dollar) 413,000,000. WTP (Willingness to Pay) of domestic tourist respondents was IDR 29,702 or USD 2.2 per visit, while the value of foreign tourist respondents reached IDR 39,700 or USD 2.9 per visit. Respondents found it preferable to pay more for tickets (WTP value) than to buy medication to reduce their stress.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.47 no.4
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• pp.177-186
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• 2015

Until Mandelbrot introduced the concept of fractal geometry and fractal dimension in early 1970s, it has been generally considered that the geometry of nature should be too complex and irregular to describe analytically or mathematically. Here fractal dimension indicates a non-integer number such as 0.5, 1.5, or 2.5 instead of only integers used in the traditional Euclidean geometry, i.e., 0 for point, 1 for line, 2 for area, and 3 for volume. Since his pioneering work on fractal geometry, the geometry of nature has been found fractal. Mandelbrot introduced the concept of fractal geometry. For example, fractal geometry has been found in mountains, coastlines, clouds, lightning, earthquakes, turbulence, trees and plants. Even human organs are found to be fractal. This suggests that the fractal geometry should be the law for Nature rather than the exception. Fractal geometry has a hierarchical structure consisting of the elements having the same shape, but the different sizes from the largest to the smallest. Thus, fractal geometry can be characterized by the similarity and hierarchical structure. A process requires driving energy to proceed. Otherwise, the process would stop. A hierarchical structure is considered ideal to generate such driving force. This explains why natural process or phenomena such as lightning, thunderstorm, earth quakes, and turbulence has fractal geometry. It would not be surprising to find that even the human organs such as the brain, the lung, and the circulatory system have fractal geometry. Until now, a normal frequency distribution (or Gaussian frequency distribution) has been commonly used to describe frequencies of an object. However, a log-normal frequency distribution has been most frequently found in natural phenomena and chemical processes such as corrosion and coagulation. It can be mathematically shown that if an object has a log-normal frequency distribution, it has fractal geometry. In other words, these two go hand in hand. Lastly, applying fractal principles is discussed, focusing on pulp and paper industry. The principles should be applicable to characterizing surface roughness, particle size distributions, and formation. They should be also applicable to wet-end chemistry for ideal mixing, felt and fabric design for papermaking process, dewatering, drying, creping, and post-converting such as laminating, embossing, and printing.

• Journal of Cadastre & Land InformatiX
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• v.51 no.2
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• pp.21-34
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• 2021

Considering the role of roads in cities and the purpose of the Road Name Address Act, it is natural that the road name of the address is registered as the nearest road section adjacent to the building. Therefore, the Enforcement Decree of the Road Name Address Act also stipulates that mayor assign building numbers based on the basic numbers of road sections adjacent to the main entrances of buildings. However, there were cases where addresses are given from distant roads rather than adjacent roads among the actual road name addresses. Most of them are caused by misinterpretation of the case where the entrance faces more than one road. In this study, institutional and systematic improvement plans were proposed with the aim of enabling accurate selection of address information reference objects by demonstrating the limitations of the current building numbering method and presenting institutional improvement plans. Road name addresses were implemented for the core purpose of improving the inconvenience of locating the lot number address. Although some still complained of the inconvenience of road name addresses, successful settlement was possible because of the intuitive principle that most countries around the world could use it and find buildings along the road. Therefore, the system and system improvement should be made quickly in terms of accurate address information quality management and revitalization of related industries.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.37 no.4
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• pp.35-45
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• 2000

The vertex-based boundary encoding scheme is widely used in object-based video coding area and computer graphics due to its scalability with natural looking approximation. Existing single framebased vertex encoding algorithm is not efficient for temporally correlated video sequences because it does not remove temporal redundancy. In the proposed method, a vertex point is selected from not only the boundary points of the current frame but also the vertex points of the previous frame to remove temporal redundancy of shape information in video sequences. The problem of selecting optimal vertex points is modeled as finding shortest path in the directed acyclic graph with weight The boundary is approximated by a polygon which can be encoded with the smallest number of bits for maximum distortion. The temporal redundancy between two successive frames is efficiently removed with the proposed scheme, resulting in lower bit-rate than the conventional algorithms.

• Korean Journal of Environment and Ecology
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• v.7 no.2
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• pp.207-212
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• 1994

The census of Amphibia fauna in Tokyusan National Park was carried out during April 10, 1993 and August 8 - August 9, 1993 at the areas of construction field of golf course in Muju Resort and the Chibong. There were 6 species of 5 genera on the 4 families, 2 orders of Amphibia in Tokyusan National Park including Hynobius leechii. Onychodactylus fischeri, and Bufo bufo gargarizans which were announced the specific wild animals with the object of conserving by The Ministry of Environment. At the area of construction field of golf course in Muju Resort, there were 5 species of Amphibia observed as Hynobius leechii, Bombina orientalis, Bufo bufo gargarizans, Rana nigromaculata, and Rana dybowskii. Onychodactylus fischeri and Rana dyhowskii were observed at the Chibong area. The Chibong inwhich was observed 9 relatively large number of individuals of Onychodactylus fischeri was revealed as an environmentally sound habitat to Onychodactylus fischeri. Whereas in the construction field of golf course, there were intended to diminishing species and population size rapidly by progress with construction works. Therefore the large construction works such as golf couse and ski slopes which were concerning to deteriorate the natural environment should be restrain in National Park for animal diversity conservative.