• Journal of Korean Society of Coastal and Ocean Engineers
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• v.19 no.5
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• pp.418-428
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• 2007

In the calculation of wave propagation by Boussinesq equation model, it is very common to experience numerical noises generated from nonlinear interaction and breaking wave occurrence, and the numerical solution is rapidly diverged unless the noises are properly controlled. A comparative study was here undertaken for the characteristics of three different lowpass filters (FFT filter, Gaussian filter and Shapiro filter) which are all designed to be applied to the interim results of numerical calculation. The numerical results obtained with application of respective filter techniques were compared with the results of an existing hydraulic experiment for the aspects of noise suppression, conservation of main signal and altering time. The results show that the Shapiro filter can be best applied with optimal choices of its element number, pass number and filtering tune interval. The combination of the number of filter element off, pass number of 50 or less, and application interval of 100 to 200 time steps generally showed good performance in both accuracy and efficiency of the numerical calculation.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.15-21
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• 2007

Due to a decreasing tendency of river runoff in the Laohahe River basin in North China, quantitative analysis was made with the aid of the conceptual Xinanjiang model under the background of nature climate variability as well as human-induced climate change according to the long-term observational hydrometeorological data. In the past, the human effect on surface water resources was estimated by investigating the impact of human activities on each item in the equation of water balance, so as to calculate water quantity of each item in the original natural status. It seems to be clear conceptually. It is appropriate just for the case of direct impact, such as water transfer from one basin to another, water storage by various scales of hydraulic projects, besides a huge amount of investigation and indeterminate statistics data when applied in practice. It is difficult for us to compute directly water consumption due to the implementation of measures for soil conservation, the improvement of farming techniques in agriculture, the growth of population in towns and villages, and the change of socioeconomic structure. In view of such situation, the Xinanjiang model was used to separate human impact from the climatic impact on water resources. Quantitatively human activity made river runoff decrease by 1.02, 50.67, 58.06 mm in 1960's, 1970's, 1980's, respectively, while by 97.2 mm in 1990's in the sense of annual average in the Laohahe River basin.

• Journal of Environmental Impact Assessment
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• v.19 no.4
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• pp.381-396
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• 2010

It is essential to consider strategies, spatial planning, and reflection of sustainability for the creation of sound urban spaces. To this end, there is a need for plans that can secure better sustainability through strategic environmental assessment (SEA) of plans. This study examined the literature and available precedent to develop a SEA model for administrative plans for urban development including metropolitan plans, urban master plans and urban management plans. In the course of development of the model, environmental issues associated with the urban plans were analyzed by classifying them into ten categories, including "spatial planning," "conservation planning," "greenbelt systems," "habitats." and etc. according to their rank. Furthermore, those issues were reflected on the development of environmental evaluation indices for the plans. Overall and detailed environmental indices that can be applied to the administrative plans for urban development including metropolitan plans, urban master plans and urban management plans were devised for five stages: (1) Establishment of development goals and strategy, (2) Analysis of current status and characteristics, (3) Conceptualization of spatial structure, (4) Planning for each department, and (5) Execution and management. Sub plans are more detailed and concrete. Criteria based on the evaluation indices, when performing evaluations on plans based on each environmental assessment index in reference to experts and the literature, were used to forecast their effects, i.e. whether they had a positive, negative, or no effect or relationship, or whether their effects was uncertain. Based on the forecasts, this study then presents means to establish more improvable plans. Furthermore, by synthesis of the effects according to each index and integration of the process, plans were analyzed overall. This study reflects the characteristics of the present time period based on issues in the SEA process and techniques in upper level administrative plans being newly established, and presents them according to the stage of each plan. Furthermore, by forecasting the effect of plans by stage, this study presents proposals for improvement, and in this aspect, can be meaningful in promoting plan improvements through SEA.

• The Journal of the Korea Contents Association
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• v.10 no.12
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• pp.181-189
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• 2010

Crafts in our country designated as an Important Intangible Cultural Property. Are protected, but not being utilized less than in everyday life. But now that the culture industry has important strategic and cultural factors that influence the competitiveness of the industrial era was. So on the activation of traditional crafts growing interest and demand, but the nature of traditional crafts are still several issues that are faced. Of course, for the protection and industrial policies and institutional mechanisms, but not without a very negative and is weak. Therefore, preservation of traditional crafts and industrial use of the technology to effectively carry out two tasks have the policy should be sought from every angle. In this study, the kind of important intangible cultural heritage of the traditional craft techniques from various angles by category, by systematically analyze the characteristics of modern man with the utilization of real-world craftsmanship with the highest tradition of finding and preserving traditional craft skills in the limit popular and can be out of the technology industry as a potential development is proposed.

• 한국문화재보존과학회:학술대회논문집
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• 2004.10a
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• pp.137-153
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• 2004

We have analyzed the ingredients of 17 pieces of Bronze Age bronze ware, and an additional 22 pieces of Koryo and Chosun dynasty bronze ware. We have also conducted analysis of the extraction sites where these bronze ware items were found. For analyzing the main ingredient the bronze ware items have been divided into 3 groups - Cu-Sn(70?75:20), Cu-Pb-Sn(70:10:10), Cu-Pb-Sn(60:10:20) type respectively. In tile cases of the Cu-Pb-Sn groups the division comes down to differences in the Cu content as the main component, and elements such as Ni, Fe, Co contribute as a micro ingredient. The geographical and periodic characteristics of ancient bronze ware items show that theircompositional element changes from Cu:Sn to Cu:Pb:Sn and the Cu content decreases with the period,while the Pb content increases with the period. Bronze ware items from Suchon Ri, Gongju (that were used in 3 B.C.) form very different categories from 3rd ${\~}$ 2nd B.C.. They additionally formed very different categories from those bronze ware items analyzed in this research. These bronze ware itemsare shown to be geographically close and periodically overlapped, but made of a new elemental composition. This shows an inflow of a production technical culture present in the new bronze wares. The main component content of Cu is lower, and the Co and Fe contents (as microelements) are much higher than that of other bronze ware items. Such facts showthat those bronze ware items used completely different materials from bronze ware items in other cultural areas, or that there were differences in smelting techniques In the places where ancient bronze ware items have been extracted, it is presumed that the materials originated from the southern parts of Korea andnorthern parts and southern parts of China. .As more bronze ware scientific research is compiled one can conclude that that there will be enough scientific evidence to study the Bronze Age culture of Koreasystematically.

• Magazine of the Korean Society of Agricultural Engineers
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• v.39 no.5
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• pp.86-96
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• 1997

The arrangement of small streams in rural area, in the past times, attached importance to the prevention of flood damage through the straightening and lining of streams. Recently, the way of small stream arrangement is introducing the idea of water friendly environment or friendly space. As a result, there has been much concern with water favorable river management model which may lead to control flood. However, it is very difficult to develop a model applicable to all types of rivers, since each river has different flow velocity, flow amount and unique ecological characteristics. In this study, photo processing technique, one of landscape simulation methods, has been adopted because it helps to visually express and comprehensively evaluate pre and post scenery and easily applicable. Some important guideline and technique for the planning of small stream landscape arrangement are mentioned in this study. The simulation system for acquiring water favorable space and arranging landscapes needs to develop database which can forecast various types of landscape. It may also be used for the bases of planning and designing river environment arrangement. Computer aided image processing system enables to make selective planning in river environment arrangement. It may also enables to develop the methods for river environment development, ecology conservation, and multipurpose space utilization. Moreover, it makes economic river arrangement by applying river environment arrangement methods relevant to geographical characteristics. There are some limitations in this study, such as shortage of exact investigation on the stream direction and velocity in landscape arrangement. Continuous monitoring and research may be required to develop techniques through the application of computer graphics and digital image processing.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1996.06b
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• pp.285-309
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• 1996

Non oxide ceramics such as nitrides of transition metals have shown significant potential for future economic impact, in diverse applications in ceramic, aerospace and electronic industries, as refractory products, abrasives and cutting tools, aircraft components, and semi-conductor substrates amid others. Combustion synthesis has become an attractive alternative to the conventional furnace technology to produce these materials cheaply, faster and at a higher level of purity. However he process os highly exothermic and manifests complex dynamics due to its strongly non-linear nature. In order to develop an understanding of this process and to study the effect of operational parameters on the final outcome, numerical modeling is necessary, which would generated essential knowledge to help scale-up the process. the model is based on a system of parabolic-hyperbolic partial differential equations representing the heat, mass and momentum conservation relations. The model also takes into account structural change due to sintering and volumetric expansion, and their effect on the transport properties of the system. The solutions of these equations exhibit steep moving spatial gradients in the form of reaction fronts, propagating in space with variable velocity, which gives rise to varying time scales. To cope with the possibility of extremely abrupt changes in the values of the solution over very short distances, adaptive mesh techniques can be applied to resolve the high activity regions by ordering grid points in appropriate places. To avoid a control volume formulation of the solution of partial differential equations, a simple orthogonal, adaptive-mesh technique is employed. This involves separate adaptation in the x and y directions. Through simple analysis and numerical examples, the adaptive mesh is shown to give significant increase in accuracy in the computations.

• Journal of the Korea Concrete Institute
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• v.17 no.2 s.86
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• pp.255-261
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• 2005

Immense quantities of coal combustion by-products are produced every year, and only a small fraction of them are currently utilized. The purpose of this study is to investigate reused techniques of coal ash in the construction field, which may contribute to the savings of building materials and conservation of environment. From the results of the compressive strength test, the elastic modulus was experimentally proposed. Also, based on the three- point-bending test, the fracture parameters - notch sensitivity, fracture energy, and initial compliance were experimentally proposed. As a result, the strength and fracture characteristics were lower than those of concrete or mortar. Also, the study showed that the deflection at a fracture decreased as the age increased and as the notch depth rate decreased. However, it was judged that its use as a building material could be expected if further research is carried out.

• Journal of the Korean Institute of Landscape Architecture
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• v.13 no.2
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• pp.13-26
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• 1985

^x The enviroment defines the living conditions for people and has at the same time the possibility to create new environment. In Korea, where the rate of urbanization reached more than 50% in 1970′s the priority has been put on the economic development and administrative function. Under the circumstance, visual environmental field was dealt lightly and it resulted in undesirable environment. The techniques of Mordern Arts (Montage, Depeysment, Tromp L′oeil, P.O.P Art, etc.) helped Super Graphics appear in the urban areas. Environmental Art has been expended into the public space and people came to recognize the Arts as the "Street Art" or "Street as Gallery". Super Graphics has four types 1) Resident′s Super Graphics ; Minority groups came to maintain social equality and rights, in cooperation with each other. Such maintenance required general urbanites to form communities which gave birth to the community art, Mural Painting. 2) Environmental Super Graphics ; Beauty has come to be stressed in order to improve the quality of urban lives in the course of inescapable urban development. Instead of renewal of all established construction conservation oriented renewal was encouraged. 3) Super Graphics as Population Arts ; In the 1960′s artists repulsed the establishments in an efforts to open new phase independent from the expressional in the arts. They recognized the relationship between painting, society and the public in different angle and tried to describe all living space on canvas. 4) Super Graphics as Advertisement ; Super Graphics functions as efficient media to deliver images to the urbanites. Super Graphics as media plays the role for political propaganda and commercial advertisements according to their purposes. In Korea, especially, it is required to introduce the environmental Super Graphics. But it is desirable to introduce Super Graphics with Korean culture and sense of beauty. Designers themselves are also required to have responsibility to improve the quality of urban culture.

• Analytical Science and Technology
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• v.26 no.3
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• pp.190-198
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• 2013

Ambers have been used mostly as beads, jewelry and ornaments from ancient times and excavated as a buried artifact. When excavated, they are severely weathered to be cracked, exfoliated and disintegrated. Monitoring of changes in composition of amber according to weathering is very important for diagnosing the condition of amber and applying conservation materials and techniques. In this study, we tried to find the components of amber by analyzing amber with pyrolysis/GC/MS. The changes in the composition of pyrolzates after artificial ageing for 60 days under heat and oxygen were also observed. Abietic acid was detected as a main component of fresh amber and monoterpene, alkene, aromatic hydrocarbon were detected as major pyrolyzates. Changes with artificial ageing was estimated by comparing the peak area ratio of 23 components, and it was found that abietic acid abruptly decreased in the presence of heat and oxygen together, revealing that oxygen is a key factor to the deterioration of amber. It was also tried to understand the weathered surface of original amber gemstone based on the result of this ageing experiment.