• Investigative Magnetic Resonance Imaging
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• v.3 no.2
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• pp.167-172
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• 1999

Purpose : To evaluate the detection rate of hyperacute intracerebral hemorrhage in echo planar imaging (EPI) and other MR sequences. materials and Methods : Intracerebral hemorrhage was experimentally induced in ten rats. EPI, fast spin-echo (FSE) T2 weighted images, fluid attenuated inversion recovery (FLAIR), spin-echo (SE) T1 weighted images and gradient echo (GE) T1 weight ed images of rat's brains were obtained 2 hours after onset of intracerebral hemorrhage. EPI and FSE T2 images were additionally obtained 30 min and 1 hour after onset of hemorrhage in 3 and 6 rat, repeatedly, For objective visual assessment, discrimination between the lesion and normal brain parenchyma was evaluated on various MR sequences by three radiologists. For quantitative assessment, contrast-to-noise ratio (CNR) was calculated fro hemorrhage-normal brain parenchyma. Statistical analysis was performed usning the Wilcoxon-Ranks test. Results : EPI, FLAIR, and FSE T2 images showed high signal intensity lesions. The lesion discrimination was easier on EPI than on other sequences, and also EPI showed higher signal intensity for the subjective visual assessment. In quantitative evaluation, CNR of the hemorrhagic lesion versus normal brain parenchyma were higher on EPI and FLAIR images (p<0.01). There was no difference in CNR between EPI and FLAIR (p>0.10). On MR images obtained 30 minutes and 1 hour after the onset of intracerebral hemorrhage, the lesion detection was feasible on both EPI and FSE T2 images showing high signal intensity. Conclusion : EPI showed higher detection rate as compared with other MR sequences and could be useful in early detection and evaluation of intracerebral hemorrhage.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.4
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• pp.74-82
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• 2008

The purpose of this study is to reflect on the results of the assessment and analysis of landscape planning projects according to planning phases in a landscape planning system based on landscape law. An assessment of the importance and performance of landscape planning elements by planning phases was studied by statistically descriptive analysis, variation analysis, statistical t-test and importance-performance analysis. As a result of the evaluation, the performance of existing landscape planning projects is 3.813 and the importance of planning elements is 5.648. This means that in spite of the importance of landscape planning elements, the performance of existing landscape planning projects is not sufficient to cover the importance of landscape planning elements. In addition, 'site landscape survey' and 'landscape design guideline' sections are not sufficient when they are compared to 'landscape concept plan' and 'landscape basic plan' to complete the landscape planning projects required by landscape law. It means also that the landscape survey and landscape design guidelines should be complementarily practiced in order to increase the effectiveness of landscape planning projects. As the research is practiced by survey methods on landscape planning projects which are only new development sites, the results cannot represent all types of landscape planning projects. Nevertheless, the results can be applied to new landscape planning at new development sites or old cities to increase effectiveness.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.16 no.2
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• pp.81-89
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• 2002

The Battery Energy Storage System (BESS) has lots of advantages such as load leveling, quick response emergency power (spinning reserve), frequency and voltage control, improvement of reliability, and deferred generation and transmission construction. However, it is very critical that economic feasibility requires justification from the customer side of meter to promoting the dissemination of BESS in nation widely. In this paper, we proposed the economic assessment model of customer owned BESS which is complemented and improved the existing model. The proposed model is applied to the typical customer types, i.e. light industrial, commercial, and residential, which are taken from the statistical analysis on the load profile survey of Korea Electric Power COmpany (KEPCO). The economic viability performed for each customer load type to justifying their economic feasibility of BESS installation from the economic measures such as payback period, Net Present Worth (NPW), Rate Of Return (ROR). The results show that the BESS has economic benefits to the specific customer type, i.e. residential customer. Therefore, the government and the energy agency should be committing the support program, such as tax incentive, financial support, to disseminate the BESS nation widely. The results of this paper are useful to the customer investment decision-making and the national energy policy & strategy in Korea.

• Journal of Science Education
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• v.41 no.3
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• pp.382-404
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• 2017

This study aims to explore a learning progression for eight core concepts of middle school science using constructed response items in the national assessment of educational achievement (NAEA). For this purpose, a total of 7,390 responses of the 9th graders on 8 constructed response items in NAEA conducted in 2015 were inputted by computer and the inputted answers were analyzed and classified into different levels. After completing this process, five levels were set for each construct and a construct map was created according to the levels. In this study, the construct map was written in a progression-based rubric format, which was used as a criterion for leveling the answers of all students. In addition, the Rasch model was applied to measure the scores and achievements of the respondents by means of statistical analysis to correlate the scores of the students with the achievement levels of the constructs. Lastly, a preliminary learning progression was created by revising the construct map reflecting the results of Rasch model application. This study was meaningful in that it explored the possibility of developing the learning process by using constructed response items in NAEA. However, the preliminary learning progression developed in this study is still hypothetical and inferential because it is not longitudinally traced to individual students. Therefore, it is necessary to continually revise and supplement through iterative research process.

• Economic and Environmental Geology
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• v.45 no.6
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• pp.697-707
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• 2012

The quantitative landslide susceptibility assessment methods can be divided into statistical approaches and geomechanical approaches based on the consideration of the triggering factors and landslide models. The geomechanical approach is considered as one of the most effective approaches since this approach proposes physical slope model and considers geomorphological and geomechanical properties of slope materials. Therefore, the geomechanical approaches has been used widely in landslide susceptibility analysis using the infinite slope model as physical slope model. However, the previous studies assumed constant groundwater level for broad study area without the consideration of rainfall intensity and hydraulic properties of soil materials. Therefore, in this study, landslide susceptibility assessment was implemented using the coupled infinite slope model with hydrologic model. For the analysis, geomechanical and hydrualic properties of slope materials and rainfall intensity were measured from the soil samples which were obtained from field investigation. For the practical application, the proposed approach was applied to Jinbu area, Gangwon-Do which was experienced large amount of landslides in July 2006. In order to compare to the proposed approach, the previous approach was used to analyze the landslide susceptibility using randomly selected groundwater level. Comparison of the results shows that the accuracy of the proposed method was improved with the consideration of the hydrologic model.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.10 no.3
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• pp.161-170
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• 2012

To provide domestic values of input parameters in a safety assessment of radioactive waste disposal under domestic deep underground environments, various kinds of experiments have been carried out under KURT (KAERI Underground Research Tunnel) conditions. The input parameters were classified, and some of them were selected for this study by the criteria of importance. The domestic experimental data under KURT environments were given top priority in the data review process. Foreign data under similar conditions to KURT were also gathered. The collected data were arranged and the statistical calculations were processed. The properties and distribution of the data were explained and compared to foreign values in view of their validity. The following parameters were analysed: failure time and early time failure rate of a container, solubility of nuclides, porosity and density of the buffer, and distribution coefficients of nuclides in the geomedia, hydraulic conductivity, diffusion depth of nuclides, groundwater flow rate, fracture aperture, length of internal fracture, and width of faulted rock mass in the host rock.

• Steel and Composite Structures
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• v.34 no.5
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• pp.681-698
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• 2020

The paper addresses contribution to the modeling and optimization of major machinability parameters (cutting force, surface roughness, and tool wear) in finish dry hard turning (FDHT) for machinability evaluation of hardened AISI grade die steel D₃ with PVD-TiN coated (Al₂O₃-TiCN) mixed ceramic tool insert. The turning trials are performed based on Taguchi's L₁₈ orthogonal array design of experiments for the development of regression model as well as adequate model prediction by considering tool approach angle, nose radius, cutting speed, feed rate, and depth of cut as major machining parameters. The models or correlations are developed by employing multiple regression analysis (MRA). In addition, statistical technique (response surface methodology) followed by computational approaches (genetic algorithm and particle swarm optimization) have been employed for multiple response optimization. Thereafter, the effectiveness of proposed three (RSM, GA, PSO) optimization techniques are evaluated by confirmation test and subsequently the best optimization results have been used for estimation of energy consumption which includes savings of carbon footprint towards green machining and for tool life estimation followed by cost analysis to justify the economic feasibility of PVD-TiN coated Al₂O₃+TiCN mixed ceramic tool in FDHT operation. Finally, estimation of energy savings, economic analysis, and sustainability assessment are performed by employing carbon footprint analysis, Gilbert approach, and Pugh matrix, respectively. Novelty aspects, the present work: (i) contributes to practical industrial application of finish hard turning for the shaft and die makers to select the optimum cutting conditions in a range of hardness of 45-60 HRC, (ii) demonstrates the replacement of expensive, time-consuming conventional cylindrical grinding process and proposes the alternative of costlier CBN tool by utilizing ceramic tool in hard turning processes considering technological, economical and ecological aspects, which are helpful and efficient from industrial point of view, (iii) provides environment friendliness, cleaner production for machining of hardened steels, (iv) helps to improve the desirable machinability characteristics, and (v) serves as a knowledge for the development of a common language for sustainable manufacturing in both research field and industrial practice.

• Korean Journal of Psychosomatic Medicine
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• v.22 no.2
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• pp.104-111
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• 2014

Objectives : The aim of this study was to investigate the relationship between metabolic syndrome and cognitive functions among chronic schizophrenia patients. Methods : The survey participants were 105(40 metabolic syndrome and 65 non-metabolic syndrome) chronic schizophrenia patients at Yang-san Hospital. Each score of cognitive test(A Korean version of the Consortium to Establish a Registry for Alzheimer's Disease Assessment Packet, stroop test), Positive and Negative Syndrome Scale, Hamilton rating scale for Depression were assessed. Statistical analysis of the relationship between various tests of A Korean version of the Consortium to Establish a Registry for Alzheimer's Disease Assessment Packet and metabolic syndrome were performed using ANCOVA and logistic regression. Results : Schizophrenia patients with lower score on construction praxia were likely to be included in Metabolic syndrome group. However, there were no significant relationships in other tests between the two groups. Conclusions : This study found metabolic syndrome caused cognitive decline in chronic schizophrenia patients, especially Construction praxia. This study could be a basis to show metabolic syndrome has to be treated appropriately in schizophrenia patients and suggests the necessity of following longitudinal designed study.

• Journal of Nutrition and Health
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• v.40 no.1
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• pp.78-88
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• 2007

The purpose of this study was to investigate dietary fat and individual fatty acids intake pattern of 174 college women living in Seoul and Gyong-gi province through internet nutritional assessment system. Each of the subjects was required to input their own food intake for three days, which included two days during the week and one day of the weekend, on the web program directly and all of the data collected were used for statistical analysis. The mean daily caloric intake of the subjects was 1,500.9 kcal which was at 71.5% of Estimated Energy Requirement (EER). Dietary fat contributed 27.6% of the total caloric intake which was slightly higher than the recommended limit of 25%. Daily cholesterol intake was 310.0 mg, which was also high to some degree. Mean daily N6 and N3 fatty acid intake was 6.1 g and 0.9 g, respectively, and calory % calculated from each were 3.63% and 0.53%. This result showed the intake of N3 fatty acid fell in Acceptable Macronutrient Distribution Ranges (AMR) $0.5\sim1.0%$ but that of N6 fatty acid was somewhat lower than the AMDR $4\sim8%$. N6/N3 ratio 8.5/l, however, was within the desirable range $4\sim10/1$. Considering overall dietary fatty acids intake, oleic acid was the most abundant, followed by linoleic and palmitic acid. And among polyunsaturated fatty acids intake, linoleic acid was exclusively high, accounting for 97.4% of total N6 fatty acid intake. On the contrary, three fatty acids, linolenic (67.3%), DHA (21.1%) and EPA (10.0%), together supplied 98.4% of total N3 fatty acid intake. Mean P/M/S was 0.9/l.1/1.0. The subjects' intake of fat, many fatty acids and cholesterol came from diverse food groups including meats, fats and oils, milk and milk products, eggs, fish, and soybean products. Nevertheless, the subjects tended to show unfavorable fat and fatty acids intake pattern in terms of quantity and quality. Based on these results, it is important to monitor dietary fat intake pattern of the general population continuously and an internet program such as the one used for this study would be valuable, especially for assessing dietary patterns in the younger generation.

• Journal of Korean Traditional Oncology
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• v.16 no.1
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• pp.1-14
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• 2011

Background and Objectives : This study is an observational study of nonequivalent control group based on time lag design in order to determine the effectiveness of gargling Hwangryunhaedok-tang (HRHDT) on stomatitis caused by chemotherapy. Methods : The study period is from July 1st, 2010 to September 30th, 2010. The subjects are 13 patients who fit the profile of the study and who are admitted in the tumor department of the regional cancer center of C University Hospital which is located in Chung-Joo City. When stomatitis occurs after chemotherapy, the level of stomatitis is assessed using oral assessment guide score and oral discomfort score. Then mix 5 g of powered HRHDT and 60 ml of distilled water, and 15 ml of the solution is given to patients 4 times per day to gargle for 1 minute. For the control group, 60 ml of Chlorohexidin gargling solution is used; everyday for one week, 4 times per day, 15 ml per gargle and gargled for 1 minute. Oral Assessment Guide score and Oral Discomfort Score are assessed at same hour everyday. Crosstabulation analysis $X^2$(${\rho}$) was used to examine the demographic characteristics and difference of the two groups by using SPSS/WIN 12.0. For mean and standard deviation, descriptive statistical analysis was used. T-test was used to determine the difference of the oral discomfort scores. Result : The study has shown that the Oral Assessment Guide score of the experimental group has decreased more with more regularity. On the third day, the score of the control group is 20.16 and the score of the experimental group was 18.75, which showed a statistically significant difference with the level of significance of p<0.05. Oral Discomfort Score of the control group's score was 13.60 on the first day and 6.80 on the seventh day and the experimental group's score was 13.00 on the first day and 2.25 on the seventh day. The experimental group's score 2.25 is statistically significantly lower than the control group's score of 6.80 with the level of significance of p<0.05. Conclusions : The HRHDT gargling solution showed more regular effectiveness compared to Chlorohexidin solution on chemotherapy-caused stomatitis. Therefore this study has shown that HRHDT gargling solution can be used as an alternative medicine.