• Journal of the Korean earth science society
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• v.38 no.2
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• pp.150-160
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• 2017

In order to determine the porosity of rock, the 'standard test method for porosity and density of rock' proposed by the Korean Society for Rock Mechanics is commonly used. However, the standard test method, which uses a drying oven, takes 8 to 24 hours to complete the test in taking samples out of the oven every four hours and measuring the weight of the specimen. To complement these disadvantages, we devised a method for measuring rock porosity by using a microwave oven. The devised method reduced the cause of errors and the inconvenience occurred in the process of weighing samples by constructing a weight monitoring system, which monitors the drying process. A suitable heating/pause time was set up to maintain the temperature of sample below $105{\pm}3^{\circ}C$ in drying process, and an alarm system was implemented in order to stop drying process when the weight change of the rock sample is within 0.1% of the initial weight. The porosity was determined from the dry weight of the sample, which was obtained by the curve fitting of weight monitoring data. Then, the porosities obtained by using the microwave oven were compared with those obtained by the standard test method. Test results using sandstone samples showed that the porosities obtained by a microwave oven was similar to those obtained by the standard method and the porosity difference between two methods was as large as 0.4%. In addition, repeated porosity measurement using the same specimen showed that the standard deviation of the porosity, which reflects the precision of the measurement was as good as 0.23%. Therefore, a microwave oven porosity measurement system can give the porosity of rock samples with high reliability.

• Management & Information Systems Review
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• v.35 no.4
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• pp.141-153
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• 2016

This study estimates the productivity change of pharmaceutical industry and decompose the change into technical efficiency change and technological change to explore ways to improve the productive efficiency. Unlike most previous studies, this study employs the non-radial and non-oriented slacks-based Malmquist productivity index which can deals directly with the input excesses and output shortfalls. In addition a smoothed bootstrap method is applied to estimate statistical confidence intervals for the Malmquist Index and its components. For the empirical analysis a balanced panel data set is constructed covering ten years over the period from 2005 to 2014. The input variables used in this study are number of workers, tangible assets and major production cost. The gross production is selected as a main output variable. The empirical results suggest that the productivity of pharmaceutical industry has decreased due mainly to decline in the technological progress rather than improvements in technical efficiency. An analysis result shows that the scale efficiency outweighs the pure efficiency in determining the technical efficiency of pharmaceutical industry. Therefore, in order to enhance the competitiveness of domestic pharmaceutical industry, it is important to continue supporting policies to promote the technology innovation capability through efficient R&D investment and industry reform strategy.

• Journal of the Korea Society for Simulation
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• v.26 no.2
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• pp.41-49
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• 2017

In the acquisition program, the conceptual design is the most important step toward specifying the military objectives, establishing requirements and determining future developmental directions, of a target system. However, if both the requirements and directions are incorrectly set due to the lack of development experiences and literature backgrounds in the target systems, such as future ground combat vehicles, it may become a major risk in the future design phases and the entire acquisition program. In order to correct these errors in the future phases, time, effort and cost are required. Therefore, it is necessary to reduce the errors that occur in the initial stages to effectively acquire the future ground combat vehicles. This paper describes the initial design method for verifying the requirements and the developmental directions and estimating the system performance at the conceptual design through the system-level physical modeling and simulation (M&S) and the target system performance analysis. The system-level physical M&S use cutting-edge design tools, model-based designs and geometric-based designs. The system performance estimation is driven from the results of the system-level physical M&S and the specialized system analysis software.

• Journal of Preventive Medicine and Public Health
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• v.9 no.1
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• pp.109-116
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• 1976

Reorganization of myun health care service is one of the main issues in health care delivery in rural Korea. The fundamenta, concept of the role and function of the myun health subcenter is that it is the basic unit of rural health care service and is to provide comprehensive health care service through the integration of curative and preventive services. The aim of this study is to analyze the patterns of curative activities in the myun health subcenter in terms of the most prevalent types of diseases, necessary diagnostic methods and required equipment, types of treatment, necessary drugs and materials, and finally the cost of curative services. The population on which this study was done was the 1596 patients who visited the two myun health subcenters (Sunwon Myun and Naega Myun) in Kang Wha County, the area of the Yonsei University Community Health Teaching Project, during period from May 1, 1975 to June 10, 1976. For the patient's record in the clinic, problem oriented medical records were used. Decisions regarding the disease classification, the diagnostic methods used and selection of the most appropriate and adequate medical treatment were made by a group of three experienced physicians after reviewing the medical records which had been written by public physicians who were treating patients in the study area. The records were reviewed by resident staff members of the Department of Preventive Medicine, of Yonsei University College of Medicine. A brief summary of results of the study is as follow: 1. 29.9% of the patients who visited the clinics were ages between 0-4. No sex difference was observed among patients less than 20 years of age. However, among patients over 20 years old, females predominated. Thus it is evident that the majority of patients were either children or mothers and grandmothers. 2. The distance from the individual villages to the myun health subcenter was one of important factors in determining the ratio of clinic visits. However, other factors such as the activities of the health workers also affected the rates substantially. 3. The most common 25 diseases comprised 90.2% of all the diseases recorded. Acute respiratory infection (25.5%), Skin (12.7%) , diarrheal diseases (6.8%), neuralgia and back pain (4.9%) and. all other injuries (3.9%) were the five most common diseases. 4. Of all the diseases diagnosed and treated, 9.2% required simple laboratory tests for diagnosis, 6.5% required X-ray examination, and altogether 13.6% required either laboratory test or X-ray examination. 5. Treatment and management of 42.0% of the cases could be accomplished with simple, inexpensive drugs, 12.8% required the use of more expensive drugs (mostly antibiotics) and injections were required in 19.7% of the cases. Minor surgery and referral were necessary in 5% of the cases. 6. The cost for diagnosis and treatment was estimated with a standard which was set by general concensus. The average cost of diagnosis was 144 per case and the cost of treatment was 726 per case, The Total average cost per visit was 870.

• Journal of Pharmaceutical Investigation
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• v.34 no.6
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• pp.521-527
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• 2004

Cimetidine is a histamine $H_2-receptor$ antagonist, used for the treatment of endoscopically or radiographically comfirmed duodenal ulcer, pathologic GI hypersecretory conditions, and active, benign and gastric ulcer. Simple method for determining cimetidine in human plasma has been developed and validated. The analytical procedure for cimetidine showed a linear relationship in the concentration ranges from $0.05\;to\;5\;{\mu}g/ml$. Coefficient of variance (CV, %) for intraday and interday validation and relative error (RE, %) were less than ${\pm}15%$. Based on this analytical method, the bioequivalence of two cimetidine 400 mg tablets, reference (Tagamet 400 mg) and test drug (Sinil CIMETIDINE 400 mg) was evaluated according to the guidelines set by the Korea Food and Drug Administration (KFDA). Release of cimetidine from the tablets in vitro was tested using KP VIII Apparatus II with various dissolution media (pH 1.2, 4.0, 6.8 buffer solutions and water). Twenty-four healthy volunteers, $21.38{\pm}1.86$ years in age and $68.71{\pm}8.68\;kg$ in body weight, were divided into two groups and a randomized $2{\times}2$ cross-over study was performed. After oral administration of a tablet containing 400 mg of cimetidine, blood samples were taken at predetermined time intervals and concentrations of cimetidine in plasma were determined using HPLC equipped with UV detector. The dissolution profiles of the two tablet formulations were very similar at all dissolution media. In addition, pharmacokinetic parameters such as $AUC_t$ and $C_{max}$ were calculated and ANOVA was employed for the statistical analysis of parameters. The results were revealed that the differences in $AUC_t$ and $C_{max}$ between the two tablets were 4.17 % and 0.97% respectively. At 90% confidence intervals, the differences in these parameters were also within ${\pm}20%$. All of the above mentioned parameters have met the criteria of KFDA guidelines for bioequivalence, indicating that the test drug tablet (Sinil CIMETIDINE tablet) is bioequivalent to Tagamet 400 mg tablet.

• Journal of the Korean Society of Groundwater Environment
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• v.6 no.3
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• pp.152-157
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• 1999

Oil leaked from underwound storage tanks and leachate from sanitary landfills have been known as contaminant sources of the high-quality groundwater resources. The mobility of contaminants in the aquifer largely depends on the groundwater flow and the determination of associated hydraulic parameters is essential for a proper remediation of contaminated grnundwater. This study aimed at determining an optimum set of hydraulic parameters for an unconfined sandy aquifer of a laboratory scale through comparison of various methods. Results showed that the specific yield obtained from gravity drainage experiment was an average of 0.20 with minor variations in aquifer depths. and the permeabilities obtained from Dupuit approximation and slug test gave similar values of 5.33 cm/min and 5.85 cm/min but the constant head method gave 0.17 cm/min, which is much ion than the other methods. This experimental evidence reveals that the permeability of the unconfined sandy aquifer could be accurately determined by Dupuit assumption or slug tut rather than by constant head method conducted for a disturbed separate soil column.

• Journal of Korean Ophthalmic Optics Society
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• v.13 no.4
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• pp.89-94
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• 2008

Purpose: To observe the high temperature creep test and the fracture surface of the samples of 9% Ni alloy steel generally used for all kinds of mahine parts and predict the durability of that by determining a constant of C with a Larson-Miller variable. Methods: The equipment of this test was made into lever-beam style designed by Andrade and F. Garofalo et al.. The condition of creep test was set under 16 kinds of conditions after fixing 4 kinds of temperature condition and 4 kinds of stress condition to check how it effects the samples. Results: The temperature of creep test was increased, the stress index (n) of creep deformation was gradually decreased from 3.97 to 3.55. The activation energy of creep deformation was decreased from 90.39 to 83.64 kcal/mol when the stress was increased. A constant of C value by calculation of larson-Miller variable was about 22 and if temperature for use is suggested, the durability could be calculated. Conclusions: By analyzing the fracture phenomenon and suggesting the observation result of the fracture surface of the samples and creep test of 9% Ni alloy steel, the basic design data for the practical use of accessories in the field of equipment could be constructed and used to predict the durability of the equipment.

• Journal of Animal Environmental Science
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• v.18 no.2
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• pp.91-94
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• 2012

This study was conducted to develop an algorithm for determination of abnormal body temperature in piglets through skin and core temperature database at normal condition. 5 piglets (mean BW : 46 kg) were employed for the experiment. They were adapted in the individual metabolism cage set at $22.5{\pm}2.0^{\circ}C$ of room temperature for 2 weeks before the measurement of body temperature. Ear, neck, head and subcutaneous neck temperature (as core temperature) of piglets were measured for every 1 minute during 30 consecutive days through 1mm k-type thermocouple wire and NI-devices (National Instruments Corporation, Austin, Texas, USA). Body temperature data were accumulated and integrated into the 1 day unit. Change of daily mean skin and core body temperatures in piglets were lowest at around 06:00, highest at around 14:00 and gradually decreased until the day after 06:00. Each skin temperatures were varied with the measuring site and largely depended on the room temperature changes. Established database of skin and core body temperature in piglets through this study can be applied to develop an algorithm for monitoring and determining the abnormal condition of animal by using radio frequency identification.

• Journal of KIISE:Computer Systems and Theory
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• v.28 no.9
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• pp.479-490
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• 2001

In this paper, we consider the method of partitioning a sphere into faces with a set of spherical convex polygons $\Gamma$=$｛P_1...P_n｝$ for determining the maximum of minimum intersection. This problem is commonly related with five geometric problems that fin the densest hemisphere containing the maximum subset of $\Gamma$, a great circle separating $\Gamma$, a great circle bisecting $\Gamma$ and a great circle intersecting the minimum or maximum subset of $\Gamma$. In order to efficiently compute the minimum or maximum intersection of spherical polygons. we take the approach of edge-based partition, in which the ownerships of edges rather than faces are manipulated as the sphere is incrementally partitioned by each of the polygons. Finally, by gathering the unordered split edges with the maximum number of ownerships. we approximately obtain the centroids of the solution faces without constructing their boundaries. Our algorithm for finding the maximum intersection is analyzed to have an efficient time complexity O(nv) where n and v respectively, are the numbers of polygons and all vertices. Furthermore, it is practical from the view of implementation, since it computes numerical values. robustly and deals with all the degenerate cases, Using the similar approach, the boundary of a general intersection can be constructed in O(nv+LlogL) time, where : is the output-senstive number of solution edges.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.6
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• pp.822-831
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• 2021

Although programs have been developed to evaluate the risk of dragging anchors, it is practically difficult for VTS(vessel traffic service) operators to calculate and evaluate these risks by obtaining input factors from anchored ships. Therefore, in this study, the gross tonnage (GT) that could be easily obtained from the ship by the VTS operators was set as an independent variable, and linear and nonlinear regression analyses were performed using the input factors as the dependent variables. From comparing the fit of the polynomial model (linear) and power series model (nonlinear), the power series model was evaluated to be more suitable for all input factors in the case of container ships and bulk carriers. However, in the case of tanker ships, the power supply model was suitable for the LBP(length between perpendiculars), width, and draft, and the polynomial model was evaluated to be more suitable for the front wind pressure area, weight of the anchor, equipment number, and height of the hawse pipe from the bottom of the ship. In addition, all other dependent variables, except for the front wind pressure area factor of the tanker ship, showed high degrees of fit with a coefficient of determination (R-squared value) of 0.7 or more. Therefore, among the input factors of the dragging anchor risk assessment program, all factors except the external force, seabed quality, water depth, and amount of anchor chain let out are automatically applied by the regression analysis model formula when only the GT of the ship is provided.