• Journal of Korea Water Resources Association
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• v.42 no.12
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• pp.1079-1089
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• 2009

The objective of this study is to develop the accurate, robust and high resolution two-dimensional numerical model that solves the computationally difficult hydraulic problems, including the wave front propagation over dry bed and abrupt change in bathymetry. The developed model in this study solves the conservative form of the two-dimensional shallow water equations using an unsplit finite volume scheme and HLLC approximate Riemann solvers to compute the interface fluxes. Bed-slope term is discretized by the divergence theorem in the framework of FVM for application of unsplit scheme. Accurate and stable SGM, in conjunction with the MUSCL which is second-order-accurate both in space and time, is adopted to balance with fluxes and source terms. The exact C-property is shown to be satisfied for balancing the fluxes and the source terms. Since the spurious oscillations in second-order schemes are inherent, an efficient slope limiting technique is used to supply TVD property. The accuracy, conservation property and application of developed model are verified by comparing numerical solution with analytical solution and experimental data through the simulations of one-dimensional dam break flow without bed slope, steady transcritical flow over a hump and two-dimensional dam break flow with a constriction.

• Journal of Animal Environmental Science
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• v.14 no.3
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• pp.183-192
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• 2008

This study was carried out to investigate the temperature, water balance, evaporation and physicochemical properties during the composting with pig slurry at a scraper system. The pig slurry was composted on farm trial using continuous aeration with turning machine for 5 month. A compost facility of rectangular concrete bin with dimension of 53 m (length) ${\times}$ 4.6 m (width) ${\times}$ 2 m (height) was bedded with sawdust. The environmental parameters were monitored in period of 5 months. The results were as follows ; 1. During the composting period, the temperature was varied in the range $50{\sim}70^{\circ}C$. The temperature of compost pile was highest in middle layer and lowest in under layer. Temperature difference between middle and under area of compost pile was $5{\sim}20^{\circ}C$. 2. The water content of compost pile varied $50{\sim}68%$. In the period of 50% of water content of compost pile, the temperature of compost was $20{\sim}30^{\circ}C$ and was not successfully composted. 3. In this study, total evaporation was 90% during composting. The amount of slurry per $1m^3$ sawdust by this method was $3.16m^3$ without treatment of effluent output. 4. The chemical properties of produced compost was high, but suitable for plant growth. Concentration of T-N, T-C in the final compost were 1.62, 34%, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.2
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• pp.143-150
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• 1998

In order to evaluate the nitrogen (N) balance, from the different application methods and levels of $^{15}N$ applied to a satsuma mandarin orchard soils in spring, we surface-applied N as urea at the rates of 50 (water-dissolved), 100 (solid and water-dissolved) and 150% (solid) of the recommended rate ($180kg\;ha^{-1}$) in spring (lebeled N), summer (nonlebeled N) with application ratio of 5:2:3. Fruit yield and quality were not significantly affected by any treatment. Nitrogen contents of spring flush leaves in late August were 3.0% regardless of the treatments. The N recovery by parts of tree itself was in the order of leaves, fruits, roots, stems, and the highest recovery per tree was 22.3% in the 50% recommended water-dissolved surface broadcast while there were not much differences for N recovery (11.9 to 13.6%) among the other three treatments. Total N content in top 30cm of soils was 0.47% regardless of the treatments, but N proportion and total residual N from the fertilizer applied increased with increasing N rate while the N recovery in soils decreased. For the recommended N rate, N proportion and the residual N from the fertilizer applied were greater in the water-dissolved surface broadcast than those in soils surface broadcast. The highest total (tree + soils) N recovery was 70.9% in the 50% recommended water-dissolved surface broadcast, but tended to decrease to 52.2, 46.6, and 43.2% for the recommended water-dissolved surface broadcast, 100 and 150% of the recommended solid surface broadcast, respectively.

• Magazine of the Korean Society of Agricultural Engineers
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• v.30 no.3
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• pp.58-68
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• 1988

Most of the Korean watersheds are mountaineous and consist of various soil types and land uses And seldom watersheds are found to have long term hydrologic records. The SNUA, a hydrologic watershed model was developed to meet the unique characteristics of Korean watershed and simulate the storm hydrographs from a small mountaineous watershed. Also the applicability of the model was tested by comparing the simulated storm hydrographs and the observed from Dochuk watershed, Gwangjugun, Kyunggido The conclusions obtained in this study could be summarized as follows ; 1. The model includes the simulation of interception, evaporation and infiltration for land surface hydrologic cycle on the single storm basis and the flow routing features for both overland and channel systems. 2. Net rainfall is estimated from the continuous computation of water balance at the surface of interception storage accounting for the rainfall intensities and the evaporation losses at each time step. 3. Excess rainfall is calculated by the abstraction of infiltration loss estimated by the Green and Ainpt Model from the net rainfall. 4. A momentum equation in the form of kinematic wave representation is solved by the finite differential method to obtain the runoff rate at the exit of the watershed. 5. The developed SNUA Model is a type of distributed and event model that considers the spatial distribution of the watershed parameters and simulates the hydrograph on a single storm basis. 6. The results of verification test show that the simulated peak flows agree with the observed in the occurence time but have relative enors in the range of 5.4-40.6% in various flow rates and also show that the simulated total runoff have 6.9-32% of relative errors against the observed. 7. To improve the applicability of the model, it was thought that more studies like the application test to the other watersheds of various types or the addition of the other hydrologk components describing subsurface storages are needed.

• Journal of East-West Nursing Research
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• v.1 no.1
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• pp.40-49
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• 1997

This study was done for understanding the desirable direction of eastern and western nursing by comparing the nursing practice for the Pyrexia patient occuring most commonly. Body temperature usually maintains around $37^{\circ}C$ owing to the thermoregulatory center but pyrexia is caused by exogenous pyrogen like infection, cancer or disturbances in body's homeostatic heat balance. Pyrexia is defined that body temperature rise above $37.2^{\circ}C$. It has chill phase, course of the fever, termination accompanied various symptoms. Oriental medicine explains that pyrexia comes from Yang's(陽) abundance and Yin's(陰) lack. Pyrexia mainly happens when body constitution is in bad condition by Six Dirty's(六陰) affection to Wi Area (偉分). It also occurs because of unbalance between Qi (氣) and Yin(陰) caused by the lack in Seven Emotions, labor, food. The Sanghanron(傷寒論), explains that pyrexia is categorized exogenous fever like Poong Han(風寒), Poong Yul(風熱), Sup Yul(濕熱) and endogenous fever due to the Qi and blood deficiency. Explained above, even though pyrexia has different meaning in oriental medicine and western medicine, but this study have compared the oriental and western medicine assuming that pyrexia is rise of body temperature. From this point of view, oriental and western nursing shows the similarity in the field of 1) use of antipyretic to control the body temperature 2) rest and comfort 3) watering 4) nutrition and case study was executed in nursing practice. From the above study, western nursing has superiority in decreasing the patient's risen body temperature using antipyretic and ice bag. But in case of empty heat, oriental nursing which recommends the patient's body keep warm and prevent the use of ice bag as the first step and helps patient's sweating by drinking of hot water was comparatively effective. In conclusion, it is desirable that oriental nursing emphasizing the supportive nursing and western nursing should be harmonized according to the status of pyrexia patient and it is needed to study the nursing method appropriate in our culture.

• Restorative Dentistry and Endodontics
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• v.9 no.1
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• pp.101-106
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• 1983

It was the purpose of this study to investigate the fracture mode of dental amalgam by observing the crack propagation, and to relate this to the microstructure of the amalgam. Caulk 20th Century Regular, Caulk Spherical, Dispersalloy, and Tytin amalgam alloys were used for this study. After each amalgam alloy and Hg measured exactly by the balance was triturated by the mechanical amalgamator (Capmaster, S.S. White), the triturated mass was inserted into the cylindrical metal mold which was 4 mm in diameter and 12 mm in height and was pressed by the Instron Universal Testing Machine at the speed of 1mm/min with 120Kg. The specimen removed from the mold was stored in the room temperature for a week. This specimen was polished with the emery papers from #100 to #200 and finally on the polishing cloth with 0.06${\mu}Al_2O_3$ powder suspended in water. The specimen was placed on the Instron testing machine in the method similar to the diametral tensile test and loaded at the crosshead speed of 0.05mm/min. The load was stopped short of fracture. The cracks on the polished surface of specimen was examined with scanning electron microscope (JSM-35) and analyzed by EPMA (Electron probe microanalyzer). The following results were obtained. 1. In low copper lathe-cut amalgam, the crack went through the voids and ${\gamma}_2$ phase, through the ${\gamma}_1$ phase around the ${\gamma}$ particles. 2. In low copper spherical amalgam, it was observed that the crack passed through the ${\gamma}_2$ and ${\gamma}_1$ phase, and through the boundary between the ${\gamma}_1$ and ${\gamma}$ phase. 3. In high copper dispersant (Dispersalloy) amalgam, the crack was found to propagate at the interface between the ${\gamma}_1$ matrix and reaction ring around the dispersant (Ag-Cu) particles, and to pass through the Ag-Sn particles. 4. In high copper single composition (Tytin) amalgam, the crack went through the ${\gamma}_1$ matrix between ${\eta}$ crystals, and through the unreacted alloy particle (core).

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.443-452
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• 1993

Direct freezing tests of soybean seed by liquid nitrogen were carried out at various moisture contents and the following important conclusions were drawn from the results of temperature measurements of soybean seed and photographs of bubbles generated on its surface : 1) Assuming that the temperature gradient in a soybean seed is negligible because of its small seed size and the freezing ratio is followed the Heiss's formula, and a differential equation based on the heat energy balance was introduced . The equation was easily solved by the Runge-Kutta-Gill method and the predicted values of the temperature were in good agreement with the observed data. 2) The photographs of bubble generation during freezing showed the boiling mode was nucleate, and then the most suitable formula on the nucleate boiling heat transfer was introduced from many formulate proposed up to now by fitting the calculated values based on the formula to the observed data. The formula used for the predict on of the seed temperature was as follows: $\frac{{\partial}T_s}{\partial\theta}\;=\;-\frac{{\alpha}(T_s\;-\;T_L)^{3.3}}{W(C_s\;-\;\frac{{\delta}m(CT_s\;+\;{\sigma})}{T_s^2})}$ where C = difference of the specific heat between pure ice and water m=moisture content of soybean seed $T_s$ = seed temperature $T_L$ = Temperature of liquid nitrogen W = mass of soybean seed $\alpha$ = proportional constant $\delta$ = constant depends on variety or the type of seed $\theta$ = time $\sigma$ = latent heat of melting of pure ice This study will give important information in the hydro-freezing technique by liquid nitrogen, available as a new technique of processing agricultural products in the near future.

• Journal of the Korean Institute of Navigation
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• v.20 no.1
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• pp.59-79
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• 1996

Waterfront redevelopment is an element in the process of inner-city regeneration now widespread in many ports of the world. Academic interest in the processes involved has yielded a literature biased towards specific locations rather than towards the analysis of processes and issues. The redevelopment of urban waterfronts does not, of course, occur exclusively in port cities but is found as a continuous process in most places where settlement and water are juxtaposed, whether or not commercial port activity is or was present. Port cities, however, as a result of the concentration and juxtaposition of urban and maritime influences, generally present the major issues involved in waterfront redevelopment most clearly. In this context, the general aim is to explore Korean dimensions of waterfront redevelopment in a range of port cities in a context of inner-urban renewal; and a specific objective is to examine the views of decision-makers in Korean port cities on the processes involved by a questionnaire method. The focus is on comparative strategies, and in particular upon the factors affecting the balance between social goals and commercial interests. To test the response of four categories of decision-makers in Korean port cities on a number of issues perceived as underpinning the processes involved in waterfront redevelopment, four catergories of respondents-port authority representatives(PO), urban planners(UP), port specialists(PS) and city-government official(GO)-were asked to fill in a questionnaire form. In three out of ten cases, the overall result broadly confirmed the a priori expectation; in six cases the confirmation was partial; and in one other the view of respondent was generally contrary to those anticipated. In many, but by no means all, cases there was substantial agreement between the four categories of respondents, but the range of scores was generally much wider than expected.

• The Korea Journal of Herbology
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• v.26 no.3
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• pp.7-14
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• 2011

Object : This study evaluated the effects of Daeseungkitang(DSK) on cerebral infarct of middle cerebral artery occlusion(MCAO). Method : Sprague-Dawley rats are used for observing to induce cerebral infraction closing its middle cerebral artery temporarily and take DSK by mouth the next 5 days, observe the amount of feces and urine. It is investigated the correlation between them after examining neurological score. Results : It is resulted the below. On the 2nd day of taking DSK, the total amount of feces of the cerebral infarct rats is increased significantly. After taking DSK, the urine volume of the cerebral infarct rats does not change at all. Taking DSK significantly improves neurological score of the cerebral infarct rats. There is a significant correlation between total amount of feces of the cerebral infarct rats and neurological score, otherwise there is no significant correlation between total amount of feces and neurological score which is taken DSK. By taking DSK, the volume of cerebral infarction does not decrease significantly. Taking DSK restrains the expression of iNOS in the cerebral cortex and striatum of the cerebral infarct rats. Taking DSK restrains the expression of MMP-9 in the cerebral cortex of the cerebral infarct rats. Taking DSK restrains the edema of astrocytes of the positive reaction of GFAP in the cerebral cortex of the cerebral infarct rats. Conclusion : According to above results, Daeseungkitang(DSK) is assumed that showing reaction of protecting neuron cell by restraint brain tissue edema thorough controlling water balance.

• Nuclear Engineering and Technology
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• v.23 no.4
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• pp.387-400
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• 1991

An ocean compartment model simulating transport of nuclides by advection due to ocean circulation and intertaction with suspended sediments is developed, by which concentration breakthrough curves of nuclides can be calculated as a function of time. Dividing ocean into arbitrary number of characteristic compartments and performing a balance of mass of nuclides in each ocean compartment, the governing equation for the concentration in the ocean is obtained and a solution by the numerical integration is obtained. The integration method is specially useful for general stiff systems. For transfer coefficients describing advective transport between adjacent compartments by ocean circulation, the ocean turnover time is calculated by a two-dimensional numerical ocean model. To exemplify the compartment model, a reference case calculation for breakthrough curves of three nuclides in low-level radioactive wastes, Tc-99, Cs-137, and Pu-238 released from hypothetical repository under the seabed is carried out with five ocean compartments. Sensitivity analysis studies for some parameters to the concentration breakthrough curves are also made, which indicates that parameters such as ocean turnover time and ocean water volume of compartments have an important effect on the breakthrough curves.