• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.5
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• pp.108-114
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• 1999

The thermal environmental chamber has been using in maintaining weather condition keeping thermal capacity under heating and cooling load fluctuation and for the performance testing of cooling system or air-conditioner on artificial envi-ronment. In ordder to make the various environmental conditions in the thermal environmental chamber the proper cooling system is necessary to eliminate the heating load produced inside the chamber and to maintain the designed environmental condition. For this reason the optimal design of cooling system and the prediction of performance is also required. This paper describes the prediction of performance of cooling system in the thermal environmental chamber with the capacity of 37,000kcal/hr which is developed for the test of performance in heating mode of heat pump system, In the results this paper is trying to develop simulation program on the base of mathematical models and which can be applied effectively to the optimal design of cooling system and prediction of performance to the inside and outside change of envi-ronmetal load.

• Journal of Environmental Impact Assessment
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• v.20 no.1
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• pp.37-48
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• 2011

Recently, the social and environmental functions of nature river are important due to the increase of expectation for river restoration. So it should be considered the effect of vegetation affecting the conveyance capacity and hydraulic resistance. However, it has not yet proposed a objective standard and modeling method to estimate the effect of conveyance capacity according to vegetaion distribution in the watercourse such as water level or velocity. Therefore, this study simulates the variations of water level and velocity using 3-dimensional hydrodynamic model, EFDC, to consider a conveyance capacity in downstream of the Soyang Reservoir. The simulation results were validated using statistical index such as F-test and T-test. As results, the water level rises about 0.01 to 0.47m and velocity difference are about -0.95m/s to 0.23m/s.

• Journal of Environmental Science International
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• v.23 no.5
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• pp.755-761
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• 2014

Tourist Psychological Capacity (TPC) is an important issue of the Tourism Capacity research. We gained the tourist satisfaction through the questionnaire investigation in Mount Tai Scenic Area and obtained the tourist satisfaction function using SPSS17.0 regression analysis method. Then we got the best psychological capacity of tourists with the Marginal Satisfaction Method. Finally we verified the influencing factors on TPC. The study found that the best TPC of Mount Tai Scenic Area is 10323 persons; Female shows lower TPC than male. Moreover, female satisfaction is more easily influenced by visitors' number increasing than male satisfaction; TPC plays negative correlation with the increasing of age. Teenagers and adults have no much difference in TPC, but the seniors present a relatively lower TPC than other; The higher education, the smaller TPC.

• Journal of Environmental Science International
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• v.4 no.5
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• pp.141-141
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• 1995

The waste biomass of Sacchromyces uvarum, used in fermentation industries to produce ethanol, were studied for their ability to absorb various heavy metal ions. Heavy metal ions studied in this research were Cd, Co, Cr, Cu, Ni and Pb. The order of the sorption capacity was Pb>Cu>Co=Cr=Cd>Ni. The living Sacchromyces uvarum exhibited higher metal-uptake capacity than the dead Sacchromyces uvarum. After we compare the uptake capacity of the Sacchromyces uvarum for individual metal ions with for a mixture of them, the following was observed: in the mixed heavy metal solution the uptake capacity was decreased than the one heavy metal solution. The selective uptake was observed when all . the heavy metal ions were dissolved in a mixed solution. The adsorption isotherm modelling was decribed with the Langmuir and Freundlich model. The results were in good agreement with the Langmuir model.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.721-728
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• 2008

Top-Base Method is a stabilization method for light weight structures particularly in the soft ground. It is widely used for the increment of bearing capacity and the effect of restraining settlement when the bearing capacity of the ground is not enough. Top-shaped cone concrete foundations are installed in graveled laid over soft ground. The principle of the basic method is to maximize effect of dispersing the overburden pressure by increasing the contact area of the top-shaped cone. Therefore, the bearing capacity is increased and the settlement is decreased by the embedded resistance of pile part in the ground. In this paper, the plate bearing test was conducted to evaluate the feasibility of Top-Base foundation. Based on the test results, the coefficient of subgrade reaction, elastic modulus, and settlement of foundation on reclaimed land was derived.

• Environmental Engineering Research
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• v.10 no.2
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• pp.79-87
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• 2005

The effects of transformation capacity on cometabolic degradation of trichloroethene (TCE) were evaluated using TCE-degrading actinomycetes pure and mixed culture under various culture conditions. The TCE transformation capacity of the actinomycetes enrichment culture in a batch test with phenol addition was 1.0 mg of TCE/mg of volatile suspended solids (VSS). The resting cell TCE transformation capacity of the actinomycetes pure culture cell was 0.75 mg TCE/mg VSS, which increased to 2.0 mg TCE/mg VSS when phenol was added as an external substrate. When the pure culture had an internal substrate in the form of poly-β-hydroxybutyrate (PHB) at 19% of the cell mass, the resting cell TCE transformation capacity increased from 0.47 to 0.6 mg TCE/mg VSS. The presence of PHB increased transformation capacity by 57%, whereas, the addition of phenol caused more than two fold increase in transformation capacity. The actinomycetes culture showed the highest transformation capacity.

• Journal of Korean Society of Water and Wastewater
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• v.27 no.1
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• pp.77-82
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• 2013

The growth and removal capacity of nitrogen and phosphorus of Chlorella vulgaris were evaluated in artificial wastewater with different nitrogen and phosphorus concentrations as element growing components for microalgae growth. The nitrogen concentration was varied in 9, 15, 30 and 60 mg-N/L with fixed phosphorus concentration of 3 mg-P/L. The growth and phosphorus removal capacity of C. vulgaris were high at initial nitrogen concentration of 15 and 30 mg-N/L, and the corresponding N/P ratios calculated were 5 and 10. In the case of varying in 1.5, 3, 6 and 10 mg-P/L of phosphorus concentration with fixed nitrogen concentration of 30 mg-N/L, the growth and removal capacity of nitrogen and phosphorus were excellent with phosphorus concentration of 3 and 6 mg-P/L. The corresponding N/P ratios were shown as 10 and 5. Therefore, the appropriate N/P ratio was concluded between 5 and 10 for wastewater treatment using C. vulgaris.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.1
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• pp.21-29
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• 2010

The concept of carrying capacity for bivalve culture of an area can be classified into four hierarchical categories, according to their level of complexity and scope, such as physical, production, ecological and social carrying capacity. Most scientific efforts to date have been directed towards modelling production carrying capacity and some of the resultant models have been used successfully. But, the modelling of ecological carrying capacity is still in its infancy, because it should consider the whole ecosystem and all culture activities. A more holistic approach is needed to determine the influence of bivalve aquaculture on the environment and ecological carrying capacity. As an alternative, we can use a set of ecological indicators which can show the environmental performance of bivalve farms and assess ecological carrying capacity. Clearance efficiency and filtration pressure indicators show the value of 0.331 and 0.203, respectively, and these indicators suggest that the present level of culture in GeojeHansan Bay is above the ecological carrying capacity of 0.05. Consequently, these indicators can provide a guidance on the present level of culture in regard to production and ecological carrying capacity in GeojeHansan Bay.

• Journal of the Korean Geosynthetics Society
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• v.13 no.2
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• pp.41-47
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• 2014

Various prediction methods for the bearing capacity of helical piles have been introduced with consideration of both the steel shaft and the helix plates attached to the shaft. In this paper, three representative methods, that is, individual bearing method, cylindrical shear method, and torque correlation method are discussed and compared to each other. The prediction methods were verified by comparing with a series of loading test results performed on moderate-size helical piles from the companion paper. As a result, the measured bearing capacity is greater than the bearing capacity predicted by the cylindrical shear method, but smaller than that of the individual bearing method. In addition, the bearing capacity predicted by the torque correlation method is in good agreement with the measured bearing capacity.

• Steel and Composite Structures
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• v.27 no.4
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• pp.417-426
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• 2018

This paper presents the seismic behaviors and restoring force model of ring beam joints of steel tube-reinforced concrete column structure under cyclic loading. First, the main failure mode, ultimate bearing capacity, stiffness degradation and energy dissipation capacity are studied. Then, the effects of concrete grade, steel grade, reinforcement ratio and radius-to-width ratios are discussed. Finally, the restoring force model is proposed. Results show that the ring beam joints of steel tube-reinforced concrete column structure performs good seismic performances. With concrete grade increasing, the ultimate bearing capacity and energy dissipation capacity increase, while the stiffness degradation rates increases slightly. When the radius-width ratio is 2, with reinforcement ratio increasing, the ultimate bearing capacity decreases. However, when the radius-to-width ratios are 3, with reinforcement ratio increasing, the ultimate bearing capacity increases. With radius-to-width ratios increasing, the ultimate bearing capacity decreases slightly and the stiffness degradation rate increases, but the energy dissipation capacity increases slightly.