• The Journal of the Korea Contents Association
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• v.10 no.4
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• pp.106-114
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• 2010

Mesh parameterization is the process of finding one-to-one mapping between an input mesh and a parametric domain. It has been considered as a fundamental tool for digital geometric processing which is required to develop several applications of digital geometries. In this paper, we propose a novel 3D volume parameterization by means that a harmonic mapping is established between a 3D volume mesh and a unit solid cube. To do that, we firstly partition the boundary of the given 3D volume mesh into the six different rectangular patches whose adjacencies are topologically identical to those of a surface cube. Based on the partitioning result, we compute the boundary condition as a precondition for computing a volume mesh parameterization. Finally, the volume mesh parameterization with a low-distortion can be accomplished by performing a harmonic mapping, which minimizes the harmonic energy, with satisfying the boundary condition. Experimental results show that our method is efficient enough to compute 3D volume mesh parameterization for several models, each of whose topology is identical to a solid sphere.

• Journal of Korean Society of Water and Wastewater
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• v.30 no.3
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• pp.253-261
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• 2016

A variety of methods for detecting the location of an underground water pipeline are being used across the world; the current main methods used in South Korea, however, have the problems of low precision and efficiency and the limitations in actual application. On this, this study developed locator capable of detecting the location of a water pipe by the use of an IMU sensor, and technology for using the extended karman filter to correct error in location detection and to plot the location on the coordinate system. This study carried out a tract test and a road test as basic experiments to measure the performance of the developed technology and equipment. As a result of the straight line, circular and ellipse track tests, the 1750 IMU sensor showed the average error of 0.08-0.11%; and thus it was found that the developed locator can detect a location precisely. As a result of the 859.6-m road test, it was found that the error was 0.31 m in case the moving rate of the sensor was 0.3-0.6 m/s; and thus it was judged that the equipment developed by this study can be applied to long-distance water pipes of over 1 km sufficiently. It is planned to evaluate its field applicability in the future through an actual pipe network pilot test, and it is expected that locator capable of detecting the location of a water pipe more precisely will be developed through research for the enhancement of accuracy in the algorithm of location detection.

• Journal of Korean Society on Water Environment
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• v.21 no.2
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• pp.169-175
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• 2005

This study was carried out to investigate the effects of irrigation water pollution on the yield and grain quality of rice. It acquires fundamental data to set up water quality standards for irrigation and produce agricultural safety products. The correlations of BOD, T-N, T-P, pH, ECw of the irrigation water with yield, grain appearance quality, and the protein content were evaluated. The field and pot experiments were conducted by using Japonica of Oryza sativa L. during 2 years. BOD concentration in irrigation water effects strongly on grain appearance quality and yield of rice. T-N in irrigation water has strong effect on the yield, appearance, and quality of rice. T-P concentration in irrigation water have not any correlation with yield and quality of rice. pH showed strongly negative correlation with maturity ratio(MTR), 1000 grain weight(TGW), and yield of rice(YLD) as r=-0.803~-0.828(p<0.001) and have no effect on the appearance quality of rice. $EC_w$ indicating salt content showed strongly negative correlation with MTR, TGW, number of grains per panicles(NGP), and number of panicles per unit area(NPM) as r=-0.759~-0.798, and with YLD as -0.753.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.454-454
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• 2011

Graphene shows unusual electronic properties, such as carrier mobility as high as 10,000 $cm^2$/Vs at room temperature and quantum electronic transport, due to its electronic structure. Carrier mobility of graphene is ten times higher than that of Silicon device. On the one hand, quantum mechanical studies have continued on graphene. One of them is quantum Hall effect which is observed in graphene when high magnetic field is applied under low temperature. This is why two dimension electron gases can be formed on Graphene surface. Moreover, quantum Hall effect can be observed in room temperature under high magnetic field and shows fractional quantization values. Quantum Hall effect is important because quantized Hall resistances always have fundamental value of h/$e^2$ ~ 25,812 Ohm and it can confirm the quantum mechanical behaviors. The value of the quantized Hall resistance is extremely stable and reproducible. Therefore, it can be used for SI unit. We study to measure quantum Hall effect in CVD graphene. Graphene devices are made by using conventional E-beam lithography and RIE. We measure quantum Hall effect under high magnetic field at low temperature by using He4 gas closed loop cryostat.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.3
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• pp.218-226
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• 1984

This study was conducted to establish fundamental of cultivation system in the southern warm region of Korea by investigation of variation of yield component and yield under the different nitrogen fertilizing levels. And that levels in this experiment were 10, 15, 20 and 25 Kg/10a. Optimum fertilizing level of nitrogen was 20 kg/10a in Seokwang variety and 25 kg/ 10a in Dongjin variety. On the optimum fertilizing level (Seokwang; 20 kg/10a, Dongjin; 15 kg/10a), the correlation coefficient between No. of panicles per unit area and the rate of ripened grains were showed negative correlation (Seokwang; r =-0.6023$\^$*/, Dongjin; r=-0.858l$\^$**/). In the primary, secondary branches and spikelets, the degeneration ratio was increased significantly under the level of N=25 kg/10a in Seokwang, N$\geq$20 kg/10a in Dongjin. In Dongjin, the rate of ripened grains was decreased with increase in nitrogen fertilizing levels and that caused to decrease the yield.

• Journal of Dairy Science and Biotechnology
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• v.23 no.1
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• pp.9-17
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• 2005

Nanotechnology has penetrated into the various branches of research and development and it is particularly of benefit to the particle size engineering. It has been widely known that the particle size of an active pharmaceutical ingredient (API) is critical in determining the bioavailability and processability of pharmaceutical formulation. However, the window of appropriate particle size has been limited mainly due to related processing difficulties. The windows have been widened by the recent development of nanotechnologies, resulting in diversified drug delivery systems. The impact of this development is far more fundamental than what can be expected from conventional particle size engineering. It is the case that the preparation and use of nanoparticles will soon be a common task in the particle engineering step of pharmaceutical unit operations. In this chapter, the basic principles of variouspreparation techniques will be discussed in detail. Regardless of processing details, the preparation methods of pharmaceutical nanoparticles mainly concern how to deal with the extra energy related with particle size. Depending on the ways of treating the e103 energy, preparation methods can be classified into two major classes, i.e.. thermodynamic and kinetic approaches. The recent progresses have shown the possibilities of much more complex combinations of different approaches and the use of new types of energy and nanostructures.

• The Journal of Industrial Distribution & Business
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• v.10 no.11
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• pp.71-80
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• 2019

Purpose: The purpose of this study is to design the curriculum of Basic College Software Programming to develop creative and logical-thinking. This course is guided by algorithmic thinking and logical thinking that can be solved by computing for problem-solving, and it helps to develop by software through basic programming education. Through the stage of problem analysis, abstraction, algorithm, data structure, and algorithm implementation, the curriculum is designed to help learners experience algorithm problem-solving in various areas to develop diffusion thinking. For Learners aim to achieve the balanced development of divergent and convergent-thinking needed in their creative problem-solving skills. Research design, data and methodology: This study is to design a basic software education for improving algorithm-thinking for non-major. The curriculum designed in this paper is necessary to non-majors students who have completed the 'Creative Thinking and Coding Course' Design Thinking based are targeted. For this, contents were extracted through advanced research analysis at home and abroad, and experts in computer education, computer engineering, SW education, and education were surveyed in the form of quasi-openness. Results: In this study, based on ADD Thinking's algorithm thinking, we divided the unit college majors into five groups so that students of each major could accomplish the goal of "the ability to internalize their own ideas into computing," and extracted and designed different content areas, content elements and sub-components from each group. Through three expert surveys, we established a strategy for characterization by demand analysis and major/textbook category and verified the appropriateness of the design direction to ensure that the subjects and contents of the curriculum are appropriate for each family in order to improve algorithm-thinking. Conclusions: This study helps develop software by enhancing the ability of students who practice various subjects and exercises to explore creative expressions in various areas, such as 'how to think like a computer' that can implement and execute their ideas in computing. And it helps increase the ability to think logical and algorithmic computing based on creative solutions, improving problem-solving ability based on computing thinking and fundamental understanding of computer coding and development of logical thinking ability through programming.

• Journal of the Korean housing association
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• v.21 no.4
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• pp.23-31
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• 2010

This study aims to examine the educational function space of university dormitories at local universities with corridor centered structure in Honam area regions based on direct and indirect parameters on the whole satisfaction of users in residential environment factors and personal characteristics. First, according to relations among parameters, educational and cultural activities of four major activities within the dormitory had indirect influences on social activities, eating and sleeping activities had no direct influence on other activities. And social activity had direct influence on the general satisfaction as an important parameter and educational and cultural activities had indirect influence on the whole satisfaction through social activities. Detailed results show that, in the first educational activities directly affecting the lighting and air conditioning facilities (0.22), safety (0.326), Territoriality (0.327), the space density (-0.167), directions (-0.166) and yeohyang having personal characteristics and the safety of the second cultural activities (0.183), Territoriality (0.361), Aesthetics (-0.13) and the personal characteristics Sex (-0.179), the direct effect, third, and erosion has a direct impact on activity The flexibility of the space factor (-0.128) and Territoriality (0.38) and the personal characteristics grade (0.172), respectively. Fourth in social activities directly affecting the pathfinding (-0.104), and parameter, education (0.388) and cultural activities (0.445), and some of the factors affecting the indirect lighting and air conditioning facilities, safety, and Territoriality, the space density, directions, grade, they could influence through educational activities to be analyzed. That is, territoriality in educational function space is the important factor that users react very sensitively in educational, eating and sleeping activities and educational function space must secure area and division considering personal and public use as the space accommodating activity which is lacking in unit residential space. Accordingly, the safety of educational function space in university dormitory is considered as the fundamental safety matter on the fire prevention, hygiene and cleanness for users in the satisfaction of educational and cultural activities.

• Transactions on Electrical and Electronic Materials
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• v.10 no.3
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• pp.97-101
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• 2009

The use of a filler material in epoxy composite materials is an essential condition for reducing the unit cost of production and reinforcing mechanical strength. However, the dielectric strength of insulators decreases rapidly due to interactions between the epoxy resin and filler particles. In contrast to existing composite materials, nano-composite materials have superior dielectric strength, mechanical strength, and enduring chemical properties due to an increase in the bond strength of the polymer and nano material, It is reported that nano-fillers provide new characteristics different from the properties of the polymer material. This study is to improve the insulation capability of epoxy resins used in the insulation of a power transformer apparatus and many electronic devices mold. To accomplish this, the additional amount of nano-$SiO_2$ to epoxy resin was changed and the epoxy/$SiO_2$ nano composite materials were made, and the fundamental electrical properties were investigated using a physical properties and an analysis breakdown test. Using allowable breakdown probability, the optimum breakdown strength for designing an electrical apparatus was determined. The results found that the electrical characteristics of the nano-$SiO_2$ content specimens were superior to the virgin specimens. The 0.4 wt% specimens showed the highest electrical properties among the specimens examined with an allowable breakdown probability of 20 %, which indicates stable breakdown strength in insulating machinery design.

• Geotechnical Engineering
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• v.8 no.3
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• pp.23-36
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• 1992

The flat dilatometer(DMT) has been practically used as an in-situ test equipment. It is a simple, rapid and cost-effective tool to characterize the in-situ stress-strain-strength properties of various types of ground materials. However, the results of flat DMT should be validated with considerable data with respect to the known reference values for a specific site. In this study, the applicability of existing relationships which were established for other local deposits is verified by performing the tests in several clay deposits. To compare with the DMT results, field vane tests and cone penetration tests were also carried out in the same field as reference tests, and unconsolidated undrained tests, oedometer tests, and other fundamental material properties tests were conducted on the thin-walled tube samples in the laboratory. The results of the flat DMT combined with empirical correlations are used to estimate soil types, unit weights, coefficients of lateral earth pressure at rest, overconsolidation ratios, constrained moduli and undrained shear strengths of three clay local deposits. It was found that various geotechnical properties estimated from the flat DMT generally well agree with those from the reference tests.