• Journal of Biosystems Engineering
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• v.35 no.4
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• pp.215-223
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• 2010

In order to develop an precision aerial pesticide application system to be attached to an unmanned helicopter which can be applied to small lots of land, this study analyzed the flowing and spraying characteristics of the spray droplets by the main rotor downwash by setting the application conditions at the flight altitude of 3 m, the diameter of main rotor of 3.1 m, the boom length of around 2.8 m, and the spraying rate of 8 L/ha. The results of this study are summarized below. Through analysis of the covering area ratio of the spray droplets by main rotor downwash by nozzle type, boom with tilt angle and height, it was found that the covering area ratio of the twin flat-fan nozzle of around 25% was more uniform than other types of nozzle, also boom with $10^{\circ}$ tilt angle and spraying height of 3 m was shown to be the appropriate conditions for aerial application of pesticides. It was found that the nozzle position to minimize the scattering loss of spray droplets due to vortex phenomenon at both ends of the main rotor was around 10 cm from the end of the main rotor. An application test for the aerial pesticide application system attached to the HUA-ACEI unmanned helicopter developed by the Rural Development Administration showed that the range of covering area ratio of the spray droplets was 10-25%, and the spraying width was approximately 7 m when over 10% of covering area ratio was considered for valid spraying.

• Journal of the Korean Society of Clothing and Textiles
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• v.18 no.3
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• pp.339-347
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• 1994

In this study the physiological significance of the upper and lower body on thermoregulation and sensation are examined. Experiments were carried out on 4 females in a climatic chamber conditioned at $25\pm1^{circ}C, 50\pm5%$ R.H.. Before the measurements, subjects were exposed to 3 types of enviromental temperature: 1) $25\pm1^{\circ}C$ for 60 min.(ST), 2) $25^{\circ}C$\rightarrow35^{circ}C\rightarrow25^{\circ}C$ for about 40 min.(HT), 3) $25^{\circ}C$\rightarrow15^{circ}C\rightarrow25^{\circ}C$ for about 40 min.(LT) covering the upper body (U) or lower body (L) with garments. 1) $T_{re}$ was significantly higher in L than in U only in 57 condition. $T_{sk}$ and Temp. under the clothing were higher in U than in L in all three conditions. Thermal sensation was warmer in U than in L, and comport sensation was most comfortable in HT condition. 2) When the upper or lower body was covered or exposed, the mean skin temperature of the upper body was higher than that of the lower body. Following covering and uncovering the same area, the changes in skin temperature were greater in the upper body than in lower body, and covering the upper body produced a greater difference of skin temperature between body and lower body than covering the lower body. 3) In all environmental conditions, when the upper body was uncovered, the skin temperatures of the chest, upper arms and forearms dropped to a considerable degree, and when the lower body was uncovered, skin temperatures of the legs showed the same pattern. On the other hand, skin temperature of the thinghs showed only little change in all cases except forehead and back uncovered or covered in two clothing types.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.15 no.6
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• pp.61-67
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• 2012

This study was conducted to evaluate the effects of soil covering and vegetation base materials implementation on the growth of Lespedeza cyrtobotrya Miq. in abandoned coal mine land. We compared the biomass of L. cyrtobotrya at the study plots of four different soil covering depth (control, 10cm, 20cm, and 30cm) and four different compounds of vegetation base materials composed of soil conditioner (S), erosion control (E), and peat moss (P) (control, S+P, E+P, and S+E+P). The result showed that the biomass of L. cyrtobotrya was higher in the study plots implemented with soil covering than control plot, although the increase in biomass was not constant with soil covering depth. In case of the vegetation base materials treatments, the biomass was highest in S+E+P plot, and S+P and E+P plots showed higher biomass than control plot.

• Journal of applied mathematics & informatics
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• v.4 no.2
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• pp.535-543
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• 1997

The application of Hadamard matrix to the paral-lel routings on the hypercube network was presented by Rabin. In this matrix every two rows differ from each other by exactly n/2 positions. A set of n disjoint paths on n-dimensional hypercube net-work was designed using this peculiar property of Hadamard ma-trix. Then the data is dispersed into n packets and these n packet are transmitted along these n disjoint paths. In this paper Rabin's routing algorithm is analyzed in terms of covering problem and as-signment problem. Finally we conclude that n packets dispersed are placed in well-distributed positions during transmisson and the ran-domly selected paths are almost a set of n edge-disjoint paths with high probability.

• Korean Institute of Interior Design Journal
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• v.23 no.3
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• pp.29-38
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• 2014

This paper is to analysis covering and exposing elements through surface in the spirit of the time through the meaning of relationship between structure and symbol(ornament) in the theory of dressing of Gottfrid Semper. In other words, The purpose is to illuminate how complementary tectonic between structure and symbolic of an architecture surface is expressed in accordance with the biased required conditions relating with the paradigm of the era. The advancement of the new method of tectonic and the new aesthetic taste have a deep relation with the reconsidering the dichotomy classification discussing a dominant position between structure and symbol(ornament). Expression of surface representing the era comes across the combined interpretation of technology, structure, and the non-physical culture's art of the community and the era.

• KIEAE Journal
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• v.9 no.3
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• pp.29-36
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• 2009

Interior material covering as the final process of house-building, critically influences not only aesthetic character but also air quality of indoor space. Wall covering today, however, caused a serious social problem because of chemicals contained in the industrial wallpaper and artificial glue. In this context, Korean traditional wall covering of Han-ji can be an alternative model due to it's ecological character. Recently 'Hanok' attracts public attention, since society and people become to appreciate the unique beauty and value of our traditional culture. The values include natural beauty, emotional character, and environment-friendliness. Recognizing this, this paper intended to scrutinize the operating process of Han-ji as an interior finish material. Historical research method was employed, tracing the related articles in old literature and interviewing with the witness of the experienced expert. Thereby, healthier and unique aesthetic indoor environment can be expected to be sustainable along with the rich cultural life of ancestors.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2010.05a
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• pp.71-72
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• 2010

The study is compared temperature history and strength of concrete followed by covering method of insulation curing of cold weather concrete with double bubble sheet. The results were as follows. First of all, in temperature history of concrete, the internal temperature of concrete fell down to $0^{\circ}C$ before/after 60 hours, having nothing to do with covering method. The study could see that, when sheet was isolated, it fell down to low temperature quickly in early curing. When the study measured compressive strength of core specimen, there were no large differences among placing methods. However, compressive strength fell down in all ages when sheet was isolated.

• Journal of the Korean Institute of Landscape Architecture
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• v.27 no.2
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• pp.51-57
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• 1999

Planting methods of seeding, seed net, sprig net and sprigging were evaluated for influence on the covering rate and the growth of Phragmites spp. The results were as follows. 1. Covering rate was high within 4 months when propagated by sprig net, seeding and sprigging but became same within 5 months afterwards regardless of Planting methods. 2. Growth of leaf height and width was high on vegetative types of Planting methods such as sprig net and sprigging when compared with on seed types of Planting methods such as seeding and seed net. 3. Sprig net showed good covering rate and growth than sprigging when compared within vegetative types of planting. 4. In this study, sprig net was figured out as the best type of Planting methods than any other types of Planting methods for the restoration of a shore vegetation in a urban stream.

• Journal of the Korean Operations Research and Management Science Society
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• v.27 no.4
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• pp.87-109
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• 2002

A satisfiability problem in propositional logic is the problem of checking for the existence of a set of truth values of atomic prepositions that renders an input propositional formula true. This paper describes an empirical investigation of a particular integer programming approach, using the set covering model, to solve satisfiability problems. Our satisfiability engine, SETSAT, is a fully integrated, linear programming based, branch and bound method using various symbolic routines for the reduction of the logic formulas. SETSAT has been implemented in the integer programming shell MINTO which, in turn, uses the CPLEX linear programming system. The logic processing routines were written in C and integrated into the MINTO functions. The experiments were conducted on a benchmark set of satisfiability problems that were compiled at the University of Ulm in Germany. The computational results indicate that our approach is competitive with the state of the art.

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.3
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• pp.452-466
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• 1996

The purpose of this study is to proviede basic data for designing sports-brassiere by a questionnaire survey about sports-brassieres preferences and physiological wearing test. The results of the survey and the physiological wearing tests on sports-brassieres are as follow; 1. According to the survey, dissatisfied factors on the sports-brassiere are "drooping and vibrating of the breasts". Preferable factors are supporting breasts by stretch and seldom changing its position by motion. The bigger cup-size and more hemispherical-type causes more discontent than flat-type. 2. The shape of breasts is oval, on what ground, horizontal line is longer than vertical. For the cross section of bust line, shirts type.brassiere is more gently curved than cup-brassiere. 3. The feeling of wearing comfort is correlated with bust.up, shield, close adhesion. The vibration of breasts is correlated with covering urea and close adhesion, and the changing band's position by movement, close adhesion. Too much covering area or strain are in inverse correlation of the comfort. 4. The rate of prevention of vibration is 75~80% on superior sports-brassieres, which has broad covering area and excellent close adhesion. adhesion.