• Journal of Korean Society of Water and Wastewater
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• v.21 no.2
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• pp.203-214
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• 2007

This study aimed at researching the process selection for two-stage and dual media filtration system, as a technology substituting the existing sand filter without expanding the site when retrofitting an old filter bed or designing a new one. In order to select the process for optimum complex filtration system, three running conditions have been tested. Test results demonstrated that Run 3 in which the 1st stage was filled with anthracite and coarse sand, and the 2nd stage was filled up with activated carbon and fine sand reduced the head loss and the load of turbidity substances. Also, Run 3 showed better performance in removing TOC, particle counts, THMFP and HAAFP, compared to other two conditions. 99 % of Cryptosporidium was removed. Bisphenol-A was rarely removed from the 1st stage of coarse sand and 2nd stage of fine sand, but 99 % of it was removed from the 2nd stage of activated carbon. In conclusion, when it is required to retrofit an old rapid filter bed or design a new one for the purpose of improving filtration performance, the following two-stage and dual media filtration system is suggested: the 1st stage of filter bed needs to be filled up with coarse sand to remove turbidity as the pretreatment for extending duration of filtering, the top part of 2nd stage needs to be filled up with granular activated caron to remove dissolved organic matters and others as the main process, and finally the bottom part of 2nd stage needs to be filled up with fine sand as the finishing process.

• Journal of Korean Society of Forest Science
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• v.62 no.1
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• pp.1-18
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• 1983

Sum of daily mean temperature, sum of daily mean relative humidity and sum of daily mean duration of sunshine during the growing season (March-October), and daily mean temperature, daily mean relative humidity and daily mean minimum temperature during the dormant season (November-February) were obtained respectively from the climactic data recorded at 26 different standard stations for 30 years from 1951 to 1980, to provide a method for proper selection of tree species suitable to a certain site. They were also marked on the map of Korea. The whole country was divided into 6 regions by trend of temperature variation and the regression equations for each region were produced to estimate the sum of daily mean temperature of the growing season and the sum of daily mean minimum temperature of the dormant season in a certain site where tree plantings are planned. The natural range of distribution of each species was expressed by the sum of daily mean temperature and daily mean minimum temperature on the basis of "Horizontal and vertical distribution of the Korean woody plants" reported by Chung and Lee (1965).

• Korean Journal of Construction Engineering and Management
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• v.21 no.6
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• pp.84-94
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• 2020

Modular architecture is very important not only in the design phase but also in the construction planning phase because it affects construction methods and module sizes depending on transport equipment. There are economic risks as well as quality, as there may be defects such as internal interiors or elimination of deadlines during transportation, and structural torsion caused by rainfall and shock. However, there is a lack of objective criteria or data to refer to in determining transport equipment that has a material effect on transport. Accordingly, there is no decision model to determine the optimum transportation equipment for each construction site. Therefore, it is necessary to develop a decision support model that can be compared to the review of transport equipment selection factors. The purpose of this study is to propose the transport equipment impact factors and decision support models for systematic review and objective decision making of each construction plan in the construction of small and medium-sized modulators. The decision model proposed in this study can be used as basic data for transport studies, ensuring objectivity and transparency in the equipment selection process.

• Journal of Korean Library and Information Science Society
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• v.38 no.3
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• pp.25-51
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• 2007

The purpose of this study is to suggest the characteristics of a cooperative storage facility for academic libraries in Korea. For this facility, discussed are how to select a site, build physical facilities, recruit participating organizations, prepare for selection criteria and ownership of resources, confirm service policies, and implement a integrated library management and access system. It is emphasized that a cooperative storage facility for academic libraries in Korea should ensure the optimum use of space on campus, preserve "the last copy" which is not frequently used, but still has scholarly values, and extend the effective and efficient resource sharing among participating libraries.

• International Journal of Fluid Machinery and Systems
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• v.8 no.4
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• pp.294-303
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• 2015

The present study is conducted to identify a better design and optimal number of Francis runner blades for sediment laden high head micro hydropower site, Tara Khola in the Baglung district of Nepal. The runner is designed with in-house code and Computational Fluid Dynamics (CFD) analysis is performed to evaluate the performance with three configurations; 11, 13 and 17 numbers of runner blades. The three sets of runners were also investigated for the sediment erosion tendency. The runner with 13 blades shows better performance at design as well as in variable discharge conditions. 96.2% efficiency is obtained from the runner with 13 blades at the design point, and the runners with 17 and 11 blades have 88.25% and 76.63% efficiencies respectively. Further, the runner with 13 blades has better manufacturability than the runner with 17 blades as it has long and highly curved blade with small gaps between the blades, but it comes with 65% more erosion tendency than in the runner with 17 blades.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.3
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• pp.297-302
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• 2008

Application of genotype by environment ($G\;{\times}\;E$) interaction would be used for identifying optimum test condition of the varietal adaptation in the establishment of breeding purpose. Yield and yield components were used to perform additive main effect and multiplicative interaction (AMMI) analysis. Significant difference for $G\;{\times}\;E$ interaction were observed for all variable examined. For yield, 0.18 of total sum of squares corresponded to $G\;{\times}\;E$ interaction. Correlation analysis was carried out between genotypic scores of the first interaction principal component axis (IPCA 1) for agronomic characters. Significant correlations were observed between IPCA 1 for yield and capsule bearing stem length (CBSL), number of capsule per plant (NOC). The biplot of grain yield means for IPCA1 which accounted for 34% of the variation in total treatment sums of squares showed different reaction according to $G\;{\times}\;E$ interaction, genotypes and environments. Taegu showed relatively lower positive IPCA1 scores, and it also showed smaller coefficient variation of yield mean where it is recommendable as a optimal site for the sesame cultivar adaptation and evaluation trial. In case of variables, Yangbaek and M1 showed relatively lower IPCA1 scores, but the score direction showed opposite each other on the graph. Ansan, Miryang1, Miryang4, and Miryang6 seemed to be similar group in view of yield response against IPCA1 scores. These results will be helpful to select experimental site for sesame in Korea to minimize $G\;{\times}\;E$ interaction for the selection of promising genotype with higher stability.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.1
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• pp.95-103
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• 2016

The absolute value management method is widely used in the most of the earth retaining construction, which evaluates the safety by comparing measurement result and management criteria. Therefore, the management criteria is the standard to evaluate the safety of the site, and in other words, the criteria is a direct factor of the evaluation. That means that the safety of the site can not be acquired if the management criteria is not proper, even though the measurement system is perfectly set. However, many of field technicians do not have rely on the current management criteria, and they even recognize the necessity of the revision. Therefore, in this study, the necessity of the revision was studied. Also, the optimum criteria selection and the application were performed based on the test results of earth retaining deflection and probabilistic theory. The absolute value management method was used for this study. The details are tabulated.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.6B
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• pp.617-625
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• 2010

The selection of a site where strong wind blows is important to increase effectively the electricity of wind power in proportion to the cube of the wind speed. It is advisable to establish the wind turbine in the coastal area with strong wind speed rather than in the inland. And the development of offshore wind energy is expected to solve the noise problem that is one of the important weaknesses in the wind turbine. In the process of the development business of wind energy, knowing forehead the wind power possibility in any area is one of the essential factors to choose the most optimum site of wind power. In this paper, the potential of wind power around JeJu coastal area is examined by using the wind data that Korea Meteorological Administration has surveyed for 10 years in 14 observation points. Wind speed data is revised to wind speed in 80 meters assuming installation height of the wind turbine, and wind power density and annual wind energy are also calculated. And annual electricity generation and percent of energy efficiency in all the observation points are estimated by using the information about 3,000 KW wind turbine.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.3
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• pp.185-191
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• 2012

Most of Korean farms have been developed in the semi-closed bay, and its position is very vulnerable to the coastal contamination due to the long term and the high density. So, mariculture management is very essential for the sustainable aquaculture. Some of the specific ways would be the assessment of the optimal stocking density for mariculture management zone and this has to consider both the suitable site selection and the assessment of ecological carrying capacity. Habitat suitability index(0.0 totally unsuitable habitat, 1.0 optimum habitat) and ecological indicator(Filtration pressure indicator) was used to assess the stocking density for oyster farms in Geoje-Hansan Bay. Geoje Bay showed the higher habitat suitability index value 0.75 than Hansan Bay 0.53, indicating that Geoje Bay is more suitable for oyster farming. Ecological indicator showed different stocking density according to the coastal characteristics in Geoje-Hansan Bay. Consequently, it is desirable that the stocking density in Geoje Bay should reduce average 40% and Hansan Bay, average 60% than present, in order to meet the ecological carrying capacity. The assessment of the stocking density could solve various problems such as the coastal contamination, environmental aggravation and the productivity decrease and this study could be a scientific basis to establish the policies for mariculture management.

• Journal of the Korea Institute of Building Construction
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• v.4 no.3
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• pp.109-116
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• 2004

Normally easy task of plat in urban architecture is that using underground full of activities for increase building site efficiency. Especially for using underground space for the parking lot. Also utilize underground is more increase for fulfill requirement in modern society considered with environmental friendly architecture. The primary objective of this study is to apply analyzed formal foundation type for selecting the optimum type of parking lots considered with structural stability, economical efficiency, construction efficiency, construction duration. This study aim to on criteria decided through the questionaries for the selection considered with in the scale of second stories parking lots underground, parking volume is 80 and reinforced concrete structure. The bearing capacity is 6～8m and downward from surface, healthy ground bearing capacity is 40 t/m2. This study comparative analysis and discuss economical efficiency, construction efficiency, construction duration based constructivist stability which applied Single foundation, Mat foundation, Drop Mat foundation. The result of this study is as follows: First, the result of economical efficiency is that on the basis of single foundation, Drop Mat foundation is 1.88, Mat foundation 2.04 as a comparative analysis on the basis of total construction cost included material cost, labor coast and machinery cost. Second, the result of construction efficiency order is single foundation, Drop Mat foundation, Mat foundation as a comparative analysis on the based connected characteristics. Third, the result of construction duration is that on the basis of Mat Foundation, Drop Mat foundation is 1.33, single foundation is 1.87 as a comparative analysis Critical Path. Forth, Each foundational type characteristics order through the matrix method is that overall each formal type of foundation contraries at economical efficiency and construction efficiency, construction duration. Also expect contradiction between engineers and owners due to engineer pursuit construction duration and ewer to begin with economical efficiency. Fifth, The selection of suitable foundation formal type needs that based consider project characteristic and field condition as according to above result of a comparative analysis. As a result, a comparative analysis economical efficiency, construction efficiency, construction duration of Mat foundation, Drop Mat foundation, single foundation with 3Bay reinforced structure underground parking lots on the healthy ground.