• Magazine of the Korean Society of Agricultural Engineers
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• v.27 no.2
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• pp.23-37
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• 1985

This studies were carried out to get characteristics of frequency distribution, probable flood flows according to the return periods, and the correlation between return periods and those length of records affect the Risk of failure in the annual maximum series of the main river systems in Korea. Especially, Risk analysis according to the levels were emphasized in relation to the design frequency factors for the different watersheds. Twelve watersheds along Han, Geum, Nak Dong, Yeong San and Seom Jin river basin were selected as studying basins. The results were analyzed and summarized as follows. 1. Type 1 extremal distribution was newly confirmed as a good fitted distribution at selected watersheds along Geum and Yeong San river basin. Three parameter lognormal Seom Jin river basin. Consequently, characteristics of frequency distribution for the extreme value series could be changed in connection with the watershed location even the same river system judging from the results so far obtained by author. 2. Evaluation of parameters for Type 1 extremal and three parameter lognormal distribution based on the method of moment by using an electronic computer. 3. Formulas for the probable flood flows were derived for the three parameter lognormal and Type 1 extremal distribution. 4. Equations for the risk to failure could be simplified as $\frac{n}{N+n}$ and $\frac{n}{T}$ under the condition of non-parametric method and the longer return period than the life of project, respectively. 5. Formulas for the return periods in relation to frequency factors were derived by the least square method for the three parameter lognormal and Type 1 extremal distribution. 6. The more the length of records, the lesser the risk of failure, and it was appeared that the risk of failure was increasing in propotion to the length of return periods even same length of records. 7. Empirical formulas for design frequency factors were derived from under the condition of the return periods identify with the life of Hydraulic structure in relation to the risk level. 8. Design frequency factor was appeared to be increased in propotion to the return periods while it is in inverse proportion to the levels of the risk of failure. 9. Derivation of design flood including the risk of failure could be accomplished by using of emprical formulas for the design frequency factor for each watershed.

• Journal of the Korean Association of Geographic Information Studies
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• v.15 no.1
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• pp.99-118
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• 2012

The aim of this study is to define a correlation between spatial distribution characteristics of FFG(Functional Feeding Groups) of aquatic insects and related environmental factors in the Geum River based on the theory of RCC(River Continuum Concept). For that objective we had used SMRA(Stepwise Multiple Regression Analysis) method to analyze close relationship between the distribution of aquatic insects and the physical and chemical factors that may affect their inhabiting environment in the study area. And then, a probabilistic method named Frequency Ratio Model(FRM) and spatial analysis function of GIS were applied to produce a predictive distribution map of biota community considering their distribution characteristics according to the environmental factors as related variables. As a result of SMRA, the values of decision coefficient for factors of elevation, stream width, flow velocity, conductivity, temperature and percentage of sand showed higher than 0.5. Therefore these 6 environmental factors were considered as major factors that might affect the distribution characteristics of aquatic insects. Finally, we had calculated RMSE(Root Mean Square Error) between the predicted distribution map and prior survey database from other researches to verify the result of this study. The values of RMSE were calculated from 0.1892 to 0.4242 according to each FFG so we could find out a high reliability of this study. The results of this study might be used to develop a new estimation method for aquatic ecosystem with macro invertebrate community and also be used as preliminary data for conservation and restoration of stream habitats.

• Journal of the Korean Institute of Rural Architecture
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• v.13 no.4
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• pp.43-50
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• 2011

Activation of conventional market in small town is important in the reinvigoration of local economy as an economical center. The revitalization of local economy is closely related to the fosterage of conventional market. So the local government is trying to activate the market. However, the projects for the activation of conventional market are mostly centered on the modernization of facilities which is carried out at urban districts. Those facilities-centered plans, being carried out at urban district, lack the consideration of the peculiarities of rural districts and the regional conditions of the conventional market in small towns. And some projects for the modernization of facilities produce negative results. Especially the conventional market in small town shows a spatial structure of a five-day market and a market place and it was influenced by the spatial relationship between the permanent market and periodic market. So analyses on the spatial lay-out and form, store facilities, spatial distribution of types of business, spatial utilization on market place are needed to improve the physical environment of the conventional market. In this context, the study analyzed systematically the space of an old and lagged Hongseong conventional market located in central district of a small town. And It is expected that the results use as a basic data to establish effective space improvement plan for conventional market in small town.

• The Korean Journal of Ecology
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• v.20 no.2
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• pp.133-143
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• 1997

From 1984 to 1989 reclaimed coastal lands in Choongnam Province of the western coast of Korea were studied for soil texture at three sites(Daeho, Hyundai A and Hyundai B) and for desalination one site(Hyundai B). The soil textures of varied sites in Hyundai A were horizontally similar and composed of 39-40% clay, 40-49% silt and 8-14% sand. But those in Da돼 and Hyundai B differed horizontally in the same area and vertically at the same site. Soil texures of Da돼 were composed of 15-17% clay, 30-45% silt and 40-55% sand and those of Hyundai B were composed of 22-45% clay, 26-49% silt and 17-31% sand. The measured electrical conductivity(EC), which represents whole salt content of the reclaimed soil, decreased year by year. The vertical distribution of the EC changed temporally and spatially in the upper zone above a 50 cm depth but not in The lower zone below a 50 cm depth. The EC valus of the soil were inversely proportional to the magnitued of annual precipitation, evaporation and the numbers of rainy days with r equalling -0.97. But the annual decrease of the EC was directly proportional to climatic factors with r=0.7. Salt in the reclaimed land was leached out by the percolative action of surplus rain water, or moved up by evaporation and carried away by running rain water. The running out of the salt on the soil surface was most efficiently carried out over 10 mm precipitation per day.

• Korean Journal of Acupuncture
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• v.29 no.4
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• pp.573-580
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• 2012

Objectives : This study was to investigate statistical validities and trends of previously reported papers that used various statistical techniques such as t-test and analysis of variance. Methods : To analyze the statistical procedures, 54 original articles using those statistical methods were selected from The Korean Journal of Acupuncture published from 2007 to 2011. Results : T-test and analysis of variance were used in 23(25.27%), and 18 papers(19.78%) out of 54 papers, respectively. Seven articles(12.96%) did not report alpha values and 26(48.15%) out of 54 studies were not tested for normal distribution. One paper(1.85%) misused t-test and 7 papers(38.89%) did not carry out the multiple comparison. Conclusions : To improve the quality of KJA, statistician involvement in research design would be necessary to reduce errors in statistical methods and interpretation of the results.

• The Journal of Engineering Geology
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• v.7 no.3
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• pp.173-189
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• 1997

A study on the geological structure and geothermal gradient distribution was carried out to evaluate the feasibility of developing a new geothermal field in the Yusong area. It is suggested that geothermal water in the Yusong area is closely related with faults, dykes, and their dipping characteristics with the study of geothermal gradient distribution. A fault of EW direction locates in northern boundary of the study area and another fault of N40{\citc}W$ crosses the EW fault at the western part of the study area. Locations of faults are recognized quite well by lineaments, geophysical exploration and geothermal gradient distribution characteristics. Three sets of dyke are found in the study area. According to the result of the geothermal gradient distribution study, the location of geothermal anomaly belt and dykes coincide each other, and the area has the temperature gradient of larger than 3$^{\circ}C$ between the depths of 0.5m and 1.0m below ground surface. The thermal anomaly belt those temperature gradient is larger than 2.5$^{\circ}C$ between the depths of 0.5m and 1.Om below ground surface is expected in the direction of N80{\citc}W$ in the study area. The dirping of dyke is almost vertical according to the linear distribution of dykes on surface and the results of geophysical survey. From the distribution of geothermal anomaly belt and the locations of dyke, three locations for the development of hot spring water could be recommended and the depth that ensure over 4$0^{\circ}C$ geotheraral water is estimated as 170~200m below the ground surface.

• Journal of the Korean Applied Science and Technology
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• v.35 no.3
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• pp.816-825
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• 2018

Recently, it was emerged to need the necessity of LPG residues management due to the finding some substances such as rust. This study is performed to investigate the characteristics of LPG residues in the production and distribution stage of LPG. For the qualitative analysis of LPG residues, it was operated to be set up the analysis conditions(the flow rate, etc) of GC-MS and was performed to analyze the component of LPG residues. From the analysis result using GC-MS, it was shown that the component of LPG residues was turned out the plasticizer to be used in the rubber manufacturing process. The inorganic components of LPG residues were analyzed using ICP-OES. At the results of inorganic analysis, it was shown that the Si element was detected, which was presumably derived from defoamers used mainly in the LPG production. Also, the P and Zn element, which are estimated to be components of grease additives used for filling facilities, were also partially detected. No trace of rusting was detected in the LPG residues in the production and distribution stages analyzed in this study. But, as plasticizers and grease additives can affect to the LPG fuel system in vehicles, it will be necessary to use the proper quality of rubber and to expand the use of low boiling grease additives.

• Journal of Ecology and Environment
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• v.29 no.1
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• pp.55-60
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• 2006

Forty six individuals out of 200 Acronicta rumicis larva were parasitized (23 %) in 2000, 14 individuals out of 60 (23.33 %) in 2001, and 14 individuals out of 62 (22.58 %) in 2002. The mean parasitism rate was $22.97{\pm}0.38%$. The parasitism rate was 36.36 % in May and 52.78 % in October, 2000, 75 % and 50% in May and October 2001, 71.4% and 47.37% in May and October 2002 and it was much higher than other months. Parasitism was occurred from May to October 2000, but it was not in June and August 2001 and June 2002. There was no difference in the monthly mean parasitism rate, but the rate was the highest in May and October. The parasitoid of the larva of A. rumicis was the highest by 77.02% of parasitic wasps, and 13.51% of parasitic flies. It was found that multiparasitism was 4.05 % and hyperparasitism was 5.41 %. In case of parasitic wasps whose parasitism rate is the highest, the rate of Braconidae and Ichneumonidae was 70.18 % and 29.82 % respectively. That is, the former has much higher parasitism rate. The parasitism rate of the larva of A. rumicis was found that Microplitis sp. is $5.28{\pm}0.63%$, Glyptapanteles liparidis $8.62{\pm}3.70%$, and Diadegma sp. $4.02{\pm}1.28%$ respectively.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.905-910
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• 2007

The cubicle of high speed train is the equipment where the important train- operating equipments are concentrated, so it requires the higher safety and reliability than any other equipment. Recently, the power car cubicle of KTX-II is, basically similar to that of KTX-I and HSR350x in its size, but consequently, as more sophisticated ATP/ATC and other parts are added, the order company points out the problem of rising temperature in summer. Especially, the interpretation about the possibility of guaranteeing the minimum freezing performance becomes necessary, when Fan Tray is out of order. This paper presents the method of improving the freezing performance while minimizing the effect of dust, and the method of guaranteeing the present freezing performance by the best arrangement of Fan Tray, when Fan Tray is out of order. And as a method of verifying this, we would like to predict the pressure, speed of a running fluid and temperature distribution of cubicle through the flow analysis.

• Journal of The Korea Institute of Healthcare Architecture
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• v.16 no.1
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• pp.25-33
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• 2010

This study is to realize the importance of the therapeutic environment of nursing facilities for elderly people; to comparatively analyze the therapeutic environment elements of the facilities in Gwangju, Jeonnam area, Seoul, and Japan by classifying the therapeutic environment elements according to two aspects on the basis of preceding studies; and to find out the differences among the three regional groupsnaFirst, all therapeutic elements were put together on the basis of two preceding studies based on the two aspects. Second, an expert group was organized primarily with architects and care-givers to find out the therapeutic environment elements of nursing facilities for elderly people with dementia, and to draw up an evaluation standard. Third, the regional differences were analyzed, by comparing the distribution of therapeutic elements of the facilities in Gwangju-Jeonnam area, Seoul, and Japan, through the found therapeutic environment elements. Consequently, eighteen therapeutic environment elements were found out of total 32 elements, and the elements were classified into nine factors based on the meaning of each element. The therapeutic environment elements were showed highest in Japan, and lowest in Gwangju-Chonnam area according to the comparative case analysis based on the nine factors. Especially, there were great regional differences in terms of awareness, safety, orientation, privacy, and freedom of choice.