• KIEAE Journal
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• v.11 no.1
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• pp.3-8
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• 2011

Sound absorbing materials used for lightweight panels and interior material are mainly made of fibroid material such as glass wool or rock wool. However these fiber type sound absorbing materials have some problems such that sound absorption could be decreased as time goes by because of durability. In addition, dust scattering from fiber type material can cause another problem in health. In this point of view, this study aims to develop environment friendly sound absorbing material using Hwangto(so called loess or yellow soil), a traditional housing material. Hwangto is natural housing material in Korea and generally known for improving indoor air quality. Hwangto panel is made to construct on the floor, wall and ceiling, and expected that there is not enough absorption. Present study tried to develop environment friendly sound absorbing material that has high sound absorption performance with good environment performance in terms of air quality. Pore rate was designed to maximize the absorption in the specific frequency bands, and two kinds of backing space were applied in order to see the effect of backing space. As a result peak frequency that has maximum absorption is going high as the pore rate is increased. The backing space provides more absorption and makes the peak frequency down to low.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.04a
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• pp.33-41
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• 2008

Architectural acoustics design of Namsadang exclusive use theaters should be designed to utilize variously to performance space that can fill flavor and taste of Namsadang performance of the Namsadang six yards. Also, analyze special quality that is sound enemy who follow in sound-absorbing materials fare arrangement of innards that is design material of architectural acoustics laying stress on tradition, use purpose and disappointment size that Namsadang exclusive use theaters seeks on the basis of specific space theme that is experience, disappointment form, seat and passageway Wall and ceiling etc. research and sound and meaning of a character wave motion powerful engineering phenomenon and reduction reverberation loss that is happened from indoor manufacturing thing reduction SCALE model of oval structure research and background of AL composition absorbing material of perforate 25% to heighten acoustic absorptivity of practical use internal organs sound absorption material emir quality sound-absorbing materials insert and layer of air most suitable reverberation time of Namsadang exclusive use theaters that 2.2m volume is $42,218\;m^3$ to become 1.2Sec architectural acoustics design do.

• Journal of information and communication convergence engineering
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• v.5 no.4
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• pp.382-388
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• 2007

Indoor location system using wireless sensor network technology was applied for the status evaluation and activity monitoring of elderly person or chronic invalid at home. Location awareness application is transparent to the daily activities, while providing the embedded computing infrastructure with an awareness of what is happening in this space. To locate an object, the active ceiling-mounted reference beacons were placed throughout the building. Reference beacons periodically publish location information on RF and ultrasonic signals to allow application running on mobile or static nodes to study and determine their physical location. Once object-carried passive listener receives the information, it subsequently determines it's location from reference beacons. By using only the sensor nodes without any external network infrastructure the cost of the system was reduced while the accuracy in our experiments. was fairly good and fine grained between 7 and 15 cm for location awareness in indoor environments. Passive architecture used here provides the security of the user privacy while at the server the privacy was secured by providing the authentication using Geopriv approach. This information from sensor nodes is further forwarded to base station where further computation is performed to determine the current position of object and several applications are enabled for context awareness.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2009.04a
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• pp.300-303
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• 2009

The purpose of this study is to grasp the preference of colors in housing spaces by different type of personality and color preference by classifying dwellers various characteristics by MBTI to obtain basic informations for the color plan that satisfies their inner desire. The results of this study are as followed. Firstly, we could say about the color distribution of living spaces like that. The ceiling and general wall showed that N(white) systems and YR of bright tone was mostly distributed. The color of floor showed that the calm tone of YR was mostly distributed. Secondly, as for the favored colors of finishing material at each space, the biggest distribution of preference color was found as N(white) group(series) in case of ceilings. As for general walls, bright tone of N(white) group showed most in living rooms. In case of that of the floor, it showed the largest distribution of calm tone of YR. Point wall was preferred bright and brilliant in various kinds of color. Thirdly, as in favor of colors of closing materials, sensible types(S) are concentrated on common color groups, on the other hand, intuition types(N) prefer color groups of various kinds not only general preferred colors.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2009.04a
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• pp.304-309
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• 2009

The purpose of this study is to develop kitchen furniture design for 40-pyung apartment Houses based on stored item of Cooking, Eating and Utility Area. The research data is gotten at a field study of stored items of Cooking, Eating and Utility Area and depth interview. The results of this study were as follows; 1)The kitchen furniture the preparation unit and the sink, the kitchen table, the heating unit and the service table, arranged at the tall storage. 2)The total bulk considered and holding volume ($2.7m^3$) with ground clearance (40%) planned with about $4.21m^3$. 3)Assumed at height and 162cm did a lower part height with 860mm and the upper depth 340mm, did with 700mm where raises. the storage the ceiling which raises will select and considered and with 2200mm did. 4)Arrangement of the kitchen the kitchen form which is an open type (L/DK or L.D.K) arranged many in forms of letter.

• KIEAE Journal
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• v.4 no.1
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• pp.11-20
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• 2004

Innovative daylighting systems in buildings in various climatic zones around the world have been developed under the IEA SHC Task21. The performance assessment were obtained by monitoring the most systems using full-scale test model rooms or actual buildings under real sky conditions. This study aims to analyze the configuration and monitoring system of the nine Mock-up models of the IEA SHC Task21 comparatively. For the purpose, the geometry of the test rooms (length, width, height, window area, glazed area and occupied), reflectance of walls, floor and ceiling, transmittance of glazing (transmittance for hemispherical irradiation, normal irradiation and U-value) were compared. And equipment for measurement (manufacturer, range, calibration, maximum calibration error, cosine response error, fatigue error), and data acquisition system (manufacturer, type, number of differential analogue input channels, A/D converter resolution in bits, data acquisition software) were also analyzed comparatively. Some findings of these experimental methodology of standard monitoring have been proven to be a valuable one for future assessment of advanced daylighting systems in our country.

• Journal of IKEEE
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• v.23 no.4
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• pp.1448-1456
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• 2019

In this study, when applying LED light sources within a single-span glass greenhouse for growing crops, the illumination simulation was performed on the ceiling and side of the glass greenhouse to determine the selective placement and effective light transmission of Si series solar cells and dye-sensitive solar cells (DSSC) for supplying LED power source. In addition, energy saving effects of glass greenhouses were analyzed for optimum lighting control when both daylight and LED light sources are considered in glass greenhouses.

• The Journal of Fisheries Business Administration
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• v.28 no.1
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• pp.1-26
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• 1997

The Proposal of this paper is to draw up solution about fishing disputes in Korea coastal waters. Small fishing vessels under 8 metric tons which is regulated by the provincial governors, must operate within provincial boundary on the sea as in fishery policy of Korea. on this, I think that the present situations of fishing disputes have related to the fishing license system. Problem of this kind, Before 1970's, fishing disputes rarely took place, and it, if any, did not bring any social conflicts or disputes. Since 1980's, some of fishing disputes have been reported within fisheries society Recently, The disputes have been increasing to become social conflicts between local people concerned and have evoked an argument on whether the provincial boundary on the sea exists. If such disputes continues to increases or remains unsolved, they will bring a tremendous social cost such as an accelerated decrease in fish resources, degradation of fishing grounds, disorder in fishing, destruction of fisheries culture and so on. The reasons for the growing disputes can be specified as fellows : the degradation of fish resources, the present fishing license system which inherently causes competitions in fish catching, irrational ceiling system of fishing vessels, legal problem on existing boundary between neighbouring two provinces, the functional problem of national or regional fishery coordination committee which has been established to coordinate general fishing disputes. This study has also dealt with Japan's experiences in fishing disputes which has the history of more than a hundred years and its coordinating mechanism. In the discussion section, some possible solutions have been briefly touched fer further study.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.10 no.1
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• pp.133-141
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• 1999

In this paper, we present an indoor propagation prediction model which is based on a three-dimensional ray-tracing technique. In this model, instead of considering all obstacles such as furnitures and fixtures, etc., only main obstacles to the propagation such as walls, ceiling and floors are modeled as slabs with finite thickness and conductivity, and the significant phenomena of propagation are considered, so we can calculate simply and predict accurately the propagation losses. The propagating rays are considered to be reflected and transmitted specularly at the boundaries of obstacles, and diffracted at edges. The reflection and transmission losses on flat obstacles are calculated by using ray tracing method, and the diffraction losses at edges are calculated by using the uniform theory of diffraction (UTD) for finite conductivity media. The results simulated for some cases by this propagation model good agree with the measured value of pathloss.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.2 no.4
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• pp.33-38
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• 1982

A successful operation of underground oil storage cavern depends on water-tightness around cavern by groundwater. If water-tightness is not secured, gas bubbles would leak out and oil would migrate to an adjacent empty cavern. In this research an electrical analogy method was employed to study the influence of shape of cavern on gas leakage and the required natural groundwater level, relative oil level in two neighboring caverns and cavern spacing to prevent oil migration. The results show that gas leakage is prevented from a cavern with a ceiling of large curvature. The required values of factors to curtail the migration of oil are given on a graph.