• Journal of the Korean Solar Energy Society
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• v.34 no.1
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• pp.58-63
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• 2014

A vertical closed loop ground source heat pump (GSHP) is used to produce heat from the low-grade energy source such as the outside air and ground source. It is known that a heat pump system type has better efficiency comparing to the electric heating system. This study only demonstrates that the vertical closed loop GSHP system is a feasible choice for space cooling of air conditioning. The coefficient of performance (COP) is the ratio of heat output to work supplied to the system in the form of electricity. For the vertical closed loop GSHP system in a cooling mode, the COP is the most commonly used way for judging the efficiency. For the purpose of this experiment, vertical closed loop GSHP system was installed in the laboratory and the experiment was executed. As a result, an average COP of vertical-closed loop GSHP system was 3.62 when the outside average temperature was $33^{\circ}C$.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1167-1174
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• 2008

Vertical drain method, which is one of the soft ground improvement methods, shorten s drain path to accelerate consolidation process and is applied in many sites. At a recent, composite discharge capacity experiment that analyze discharge amount by consolidation behavior with overburden pressure of soft ground in laboratory, simulates similarly with actuality. Geotechnical engineering problems such a s soft ground improvement are solved by numerical analysis by development of computer and numerical analysis techniques. Numerical analysis does that result is contrary by user's inexperience for choice of constitution model and application of analysis method. Therefore, this thesis experiments on composite discharge capacity test and study discharge capacity of drain and consolidation behavior of soft ground installed prefabricated vertical drain boards. Also, This thesis studied reasonable input parameters and constitution model by compare results of composite discharge capacity test and numerical analysis using PLAXIS that is 2D finial element numerical analysis program.

• Journal of international Conference on Electrical Machines and Systems
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• v.2 no.3
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• pp.349-355
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• 2013

This paper presents the multi-objective optimisation of an Inductive Coupled Power Transfer (ICPT) device. A setup as complicated as the one at hand in this paper is extremely hard to model analytically. To acquire some knowledge about the influence of the geometric factors, a sensitivity analysis is first performed using design of experiment (DoE) and finite-element modelling (FEM). It allows validating that the choice of the free factors is relevant. This being done, the optimisation itself is performed using a genetic algorithm (GA), with two objectives and a strict functioning constraint.

• Journal of Environmental Science International
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• v.33 no.2
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• pp.179-185
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• 2024

This study aimed to evaluate the differences in canine preferences for pet food terrine according to the processing method. As companion dogs, three male Spitz canines (average age 12 years, average weight 7 kg) and three male Spitz mix canines (average age 12 years, average weight 5 kg) were used in Experiment 1, whereas five male (average age 10 years, average weight 9 kg) and five female Shetland Sheepdogs (Sheltie, average age 10 years, average weight 8 kg) were used in Experiment 2, to evaluate their preferences and intake types. In both experiments, all dog categories mostly preferred 'meat' when it came to their first choice of food consumed, followed by 'vegetables', 'mixed eating', and 'vegetable leftover' last. This confirms means that canines are carnivores, and over time, choosing 'vegetables' or 'vegetable leftovers' as a secondary or alternate food source can be considered a natural process. When provided various terrines, canines in both experiments first ingested 'cooked' rather than 'freeze-dried' duck, chicken, beef, and pork terrines when selecting food at the start of feeding. For both experiments, most of the intake types using duck, chicken, beef, and pork terrine showed a preference for 'after consuming cooked terrine first and then intake freeze-dried' item. In conclusion, the reason for preferring cooked terrine can be attributed to the difference in the preparation cooking method of freeze-dried cooked terrine.

• Journal of The Korean Association For Science Education
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• v.32 no.1
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• pp.15-29
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• 2012

The purpose of this study was to investigate the educational factors on career choice of science-gifted students to science and technology bound universities and the difference of perception in regards to group factors. In addition, this study aimed to examine the effects of science-gifted education and critical events in relation to career choice to science and technology bound universities. For the study, 104 university freshmen, 75 males and 29 females, were sampled from UNIST (Ulsan National Institute of Science and Technology), that many science high school graduates entered this year. The survey was conducted with questionnaires to do with the perceptions concerning career choice and educational factors that cause them to choose such career directions. The educational factors on career choice to science and technology bound universities were classified as 3 main categories such as educational environment factor (teaching-learning factor), human factor, attitude towards science factor and the subcategories within each category. The research findings are as follows: First, the factors were closely connected with each other and 'the project centered classes' were highly interrelated with other educational environment factors such as 'the experiment activity and environment for the activity' and 'influence of teachers (professors).' Second, the female students and graduates of the science high school were more positively influenced by the educational environment and human factors on their decision for career than male students and graduates of the general high school. Third, this research found that historical scientific knowledge, perception of scientists' social status and job applications in the science field gave less influence rather than other factors on their decision for career. As a result of examining critical events for science-gifted education in relation to career choice to science and technology bound universities, numerous students mentioned that the extracurricular science activities such as science camps and field trips gave significant effects on students' career choices to science and engineering fields.

• KSTLE International Journal
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• v.2 no.2
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• pp.85-92
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• 2001

The variation of contact traction induced by different contact shapes is studied experimentally and theoretically. Considerations fer the contact shape are rounded, truncated and truncated with rounding punches. A fretting wear experiment is conducted with the contact configuration of the strip on the tube specimens. The strip specimen is pressed to form the end profile of a rounded and truncated with rounding punches shape. Wear on the tube is investigated, which is regarded as the slip region of the contact surface. Taken into consideration is the general solution of the normal traction in the case of the indentation by a punch with its end profile of the combination of parabolas. Then, partial slip solution is obtained numerically, which is compared with the wear on the tube. The radius of the rounding and the obliquity of the edge truncation affect the tractions considerably. It is found that the proper choice of the end profile can restrain the contact-induced failure such aswear.

• Bulletin of the Korean Chemical Society
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• v.24 no.6
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• pp.744-750
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• 2003

In quantum dynamics of many-body systems, to identify the Hamiltonian becomes more difficult very rapidly as the number of degrees of freedom increases. In order to simplify the dynamics and to deduce dynamically relevant Hamiltonian information, it is desirable to control the dynamics to lie within a reduced space. With a judicious choice for the cost functional, the closed loop optimal control experiments can be manipulated efficiently to steer the dynamics to lie within a subspace of the system eigenstates without requiring any prior detailed knowledge about the system Hamiltonian. The procedure is simulated for optimally controlled population transfer experiments in the system of two degrees of freedom. To show the feasibility of steering the dynamics to lie in a specified subspace, the learning algorithms guiding the dynamics are presented along with frequency filtering. The results demonstrate that the optimal control fields derive the system to the desired target state through the desired subspace.

• Journal of the Korean Statistical Society
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• v.35 no.2
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• pp.201-212
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• 2006

The technique of foldover is usually used by experimenters to de-alias the effects that are interesting in follow-up experiment. Employing a $2^{k-p}$ design with resolution III or higher, Li and Lin (2003) developed an algorithm and used computer programs to search its corresponding optimal foldover design for selected 16-run and 32-run experiments. Based on the minimum aberration criterion, the strong combined-optimal design, defined by Li and Lin, is the better choice of the initial design. In this article, we apply the technique of blocking to find the strong combined-optimal designs. Furthermore, we will tabulate all 16-run and 32-run strong combined-optimal designs and their corresponding core foldover plans for practical use. Some new designs that have not appeared in the other literature but constructed by the technique of blocking are also proposed in this article.

• International Journal of Precision Engineering and Manufacturing
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• v.2 no.1
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• pp.87-93
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• 2001

A reliable analytic model that determines the exit cross sectional shape a workpiece(material) in round-oval (oroval-round) pass sequence has been developed. The exit cross sectional shape of an outgoing workpiece is predicted by using the linear interpolation of the radius of curvature of an incoming workpiece and that of roll groovw to the roll axis direction. The requirements placed on the choice of the weighting function were to ensure boundary conditions specified. The validity of the analytic model has been examined by not rod rolling experiment with the roll gap and specimen size changed. The exit cross sectional shape and area of the workpiece predicted by the proposed analytic model were good agreement with those obtained experimentally. We found that the analytic model has not only simplicity and accuracy for practical usage but also save a large amount of computational time compared with finite element method.

• Journal of Broadcast Engineering
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• v.24 no.7
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• pp.1246-1258
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• 2019

Since light field (LF) image has huge data volume, it requires high-performance compression technique for efficient transmission and storage of its data. Camera users may like to represent parts of image at different levels of focus at their choice anytime. To address this refocusing functionality, in this paper, we first render a focal stack consisting of multi-focus images, then compress it instead of original LF data. The proposed method has advantage of minimizing the amount of LF data to realize the targeted refocusing applications. Our experiment results show that the proposed method outperforms the state-of-the-art for LF image compression method.