• Journal of Environmental Impact Assessment
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• v.23 no.6
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• pp.517-526
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• 2014

This paper performed studies on a guide for an environmental assessment necessary to select railroad route optimally, and presented techniques for an environmental friendly route selection using AHP(Analytical Hierarchy Process) as an objective method. The AHP is an approach to decision making that involves multiple choice criteria into a hierarchy and assessing the relative importance of each criterion, and determining an overall ranking of the alternatives. For the purpose of this study, we established the weight and the order of major environmental assessment items based on the survey of experts. The results of the weight by AHP were in order of Fauna & Flora, Topography & Geology, Nature Environmental Assets, Noise & Vibration, Water Quality, Landscape and Air Quality indicating natural environment should be in priority. To develop the more efficient environmental friendly route selection systems, it is necessary to consider economical, technical, and social aspects in addition to environmental consideration.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.36 no.3
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• pp.195-201
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• 2000

This paper discusses methods for the stable bottom detection and the optimum bottom offset which enable to separate the fish echoes from the bottom echoes with echo integration of demersal fish. In preprocessing of the echo signal, the bottom detection has to be done stably against the fluctuation of echo level and the bottom offset has to be set to a minimum height such that near bottom fish echoes are included Two methods of bottom detection, namely echo level threshold method and maximum echo slope method were compared and analyzed. The echo level method works well if the ideal threshold level was given but it sometimes misses the bottom because of the fluctuation of the echo. Another method to detect the bottom which uses maximum echo slope indicates the simple and stable bottom detection. In addition, the bottom offset has to be set near to the bottom but not to include the bottom echo. Optimum bottom offset should be set a few samples before the detected bottom echo which relates the beginning of pulse shape and acoustic beam pattern to the bottom feature.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.26 no.4
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• pp.353-359
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• 1990

Chinhae Bay, included small ports, is the region which the red tide phenomenon is occurred frequently in summer season. Field sampling of 4 cross-sections in the bay resulted in detailed informations on cross-sectional velocity distributions, salt concentrations and discharge during one consecutive tidal cycle in summer season, 1983. High velocity cores reoccur two times a semi-diurnal tidal cycle at the same cross-sectional location, lower layer, in Kadok Channel during the spring tide. The tidal exchange ratio was estimated by Eulerian method. The range of exchange ratios in central Kadok Channel are 9.3-17% at the spring tide and 16.9-21.8% at the neap tide. On the other hand, its range in Masan bay-mouth is 8.7% at the spring tide and 2.0% neap tide, respectively.

• Science of Emotion and Sensibility
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• v.13 no.3
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• pp.493-500
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• 2010

The development of new technology and diversity in user needs lead mobile phone manufacturers to establish new strategies different from the existing for user attraction. Product identity, and brand image are major strategies for differentiation and adding new values to a product. This research starts with stating emotional brand image as the brand image made by the actual usage and the emotion built from the experience while using the product. This research will compare emotional brand image of the three major mobile phone manufactures in Korea (Brand A, C, and S) using evaluation of six representative emotions from users while using the product. The result of evaluating actual mobile phone users and the emotion built while actually using the product showed the brand image, and especially the emotional side of Korean mobile phone manufacturers. The result of this research itself would not be sufficient to simply state the emotional brand image of Korean mobile phone manufactures, but with further research including age, profession, gender and other demographic factors the result of this research would surely be able to abstract a clearer view of emotional brand image of Korean mobile phone manufactures.

• Tunnel and Underground Space
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• v.17 no.4
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• pp.322-331
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• 2007

Hundreds of rock slopes are constructed along the road, highway and railroad in mountainous Kangwon province and managed by each authorities concerned. It is practically not possible to carry out detailed rock slope investigation owing to the tremendous number of slopes and budgetary limit. Therefore, it is reasonable to perform a step-by-step investigation consisted of basic and detailed survey program and practical rock slope hazard assesment method for person in charge is strongly required. Through the development and application of KSMR (Korean Slope Mass Rating), it was found that KSMR could be practically used as an alternative of SMR though the number of inputs were reduced. In addition, the difference of hazard assessment between KSMR and experts decreased in case of considering the height of slope.

• Tunnel and Underground Space
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• v.19 no.3
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• pp.226-235
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• 2009

Force induced by the natural ventilation in tunnel is likely to generate adverse influences on the airflow during the normal operation and create even more unfavorable circumstances during the tunnel fire. The influence of the natural ventilation is required to take into account in designing and operating the ventilation as well as safety systems. The magnitude of natural ventilation force depends on a variety of factors associated with the topographical, meteorological and physical features of tunnel. Unfortunately, at this moment those are difficult to quantify and none of the countries has suggested its estimation method in the design guideline. This study aims at quantifying the natural ventilation force at a local highway tunnel by three different methods. The first method employes direct measurement of the pressure at portals, while the second applies a stepwise approach to eliminate the piston effect ahead of deriving the natural ventilation force and the third method uses the concept of barometric barrier.

• Water for future
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• v.28 no.5
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• pp.117-127
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• 1995

The application and analysis for the scale considering GIUH model proposed by the authors in this issue have been performed for the leemokjung sub-basin in the Pyungchang basin one of IHP representative basin in Korea. Scales of topographic maps for model application and fractal analysis are 1:25,000, 1:50,000 and 1:100,000. The ratio between successive scales is therefore constant. Link lengths were measured using a curvimeter with the resolution of 1 mm. Richardson's method was employed to have fractal dimension of streams. Apparent alternations of parameters were found in accordance with variations of map scale. And this tendency could mislead physical meanings of parameters because model parameters had to preserve their own value in spite of map scale change. It was found that uses of fractal transform and Melton's law could help to control the scale problem effectively. This methodlogy also could emphasize the relationship between network and basin to the model. To verify the applicability of GIUH proposed in this research, the model was compared with the exponential GIUH model. It is proven that proposed 2-parameter gamma GIUH model can better simulate the corresponding runoff from any given flood events than exponential GIUH model. The result showed that 2-parameter gamma GIUH model and fractal theory could be used for deriving scale considered IUH of the basin.

• Water for future
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• v.20 no.4
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• pp.267-278
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• 1987

This study aims at the decision of geomorphologic instantaneous unit hydrograph(GIUH) model parameter fore the ungaged or the data deficiented Basin, to analyze rainfall runoff relation in river basin by applying queueing theory with geomorphologic factors.The concept of GIUH model is based upon the principle of queueing theory of rain drops which may follow many possible routes during rainfall period within watershed system to ist outlet. Overland flow and stream flow can be simulated, respectively, by linear reservoir and linear channel conceptual models. Basically, the model is a mon-lineal and time variant hydrologic system model. The techniques of applying are adopted subarea method and mean-value method, the watershed is divided according to its stream number and order. To prove it to be applicable, the GIUH model is applied to the Wi-Stream basin of Nak-Dong River(Basin area; 475.53$\textrm{km}^2$), southen part of Korea. The simulated and the observed direct runoff hydrographs are compared with the peak discharge, times to peak and coefficients of efficiency, respectively, and the results show quite satisfactory.Therefore, th GIUH model can be extensively applied for the runoff analysis in the ungaged and the data deficiented basin.

• Water for future
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• v.18 no.2
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• pp.175-185
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• 1985

This paper discusses the posibility of synthesizing flood hudrographs by the stroage function model. Eight small watersheds from Han, Gum, Nakdong, Youngsan river system were selected for this purpose. The optimum constants are computed from the chi square criterion by the SDFP methods Based on these constants, equations for the storage constant and Lag time are derived from the kinematic wave theory and storage function theory. These relations are examined by using optimum constants of the storage function model and assumptive constant of the kinematic wave model. Main results are sumarized as follows. 1. Constants of the storage function model are closely related to those of the kinematic wave model. The formula obtained theoretically is difficult to use practically because of the unclaified definition of factors. 2. In order to estimate constants of the storage function model for the practical purpose, new equations are also proposed for mountaneous area. 3. The verification of proposed equation is made for several recorded floods for mountaeous areas.

• Korean Journal of Microbiology
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• v.22 no.1
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• pp.1-18
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• 1984

With 156 water samples collected from 39 locations in the Yeong San River estuary during the 12month period from March 1976 to February 1977, the seasonal distribution of yeast and the distributional pattern of yeast on salinity gradient have been investigated. An overall average number of yeast ranged from 52 to 487 viable cells (c.f.u.) per 100ml water sample. The highest count of yeast was obtained in spring while the lowest value came in summer. 933 yeast and one yeast-like fungus pertaining to 14 genera and 83 species were recovered, of which Candida were 29%, Debaryomyces 17.3%, Rhodotorula Glutinis were dominant forms in all locations as well as throughout the year. The population size of total aerobic bacteria, the amount of terrestrial imputs, and some of geographical and/or climatic factor appear to reflect the seasonal distribution of yeast as well as the composition of yeast species in an estuarine environ. Average number of yeast, species diversity, and particularly the number of fermentative and pseudomycelium-producing yeasts increased with decreasing salinity whereas nitrate-utilizing yeasts showed opposite trend, suggesting that salinity gradient can be used as a feasible detector for the distributional pattern of yeast in estuarine habitat.