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Survey on the Present Condition of Mathematics Education in Art High Schools in Korea (예술계 고등학교 수학과의 수학교육 현황과 수업 실태 분석)

  • 홍석강;이방천
    • The Mathematical Education
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    • v.41 no.2
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    • pp.139-155
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    • 2002
  • In this paper we represented the results of surveying on the present condition of mathematics education and the contents of the mathematics text books that are usually taught in Art High Schools interest in mathematics subjects and to achieve the higher level of mathematical abilities. We would like to raise their interest in mathematics and to improve the efficiency of teaching level on the basis of the 7th Mathematics Curriculum Revision. Some suggestions are of offered by considering the level of their mathematical abilities in Art High Schools and the present contents of the mathematical subjects from following views ⑴ the aspect of studying method ⑵ the aspect of revising contents of mathematics textbooks for them ⑶ the aspect of educational policies for Art High Schools

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Carrier Comparison PWM Method of Vienna Rectifier for Reduction of Common Mode Voltage (비엔나 정류기의 공통모드 전압 저감이 가능한 캐리어 비교 PWM 기법)

  • Lee, Dong-Hyun;Choi, Won-Il;Hong, Chang-Pyo;Kim, Hag-Wone;Cho, Kwan-Yuhl
    • The Transactions of the Korean Institute of Power Electronics
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    • v.21 no.2
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    • pp.126-133
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    • 2016
  • This paper proposes a new PWM method to reduce the common mode voltage change in three-level Vienna rectifier. This new proposed PWM method uses medium voltage vector for the three-level Vienna rectifier to determine the sum of three-phase voltage zero, and the common mode voltage variation is decreased. Using the carrier comparison method, the switching function generator for three-level Vienna rectifier has been proposed. The effects of the proposed PWM method have been verified through simulation using the PSIM.

The comparison between the prosodic and harmonic aspects: Stress shift (운율 측면과 조화이론 측면의 비교: 강세 현상에 대해)

  • Oh, Kwan-Young
    • English Language & Literature Teaching
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    • v.7 no.2
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    • pp.147-166
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    • 2002
  • The purpose of this paper is to explain stress shift and its following segmental variations when some suffixes are added to the bases. In the past those were analyzed in stress or vowel laxing phenomenon separately, but rather those should be analyzed in one framework compositively. Therefore in this paper I will introduce a new theory, which is known as Harmonic theory, and confirm that it can solve the problems related with stress and vowel laxing simultaneously. The first thing, as a prosodic approach I am going to analyze vowel laxing according to Liberman & Prince (1977), Burzio (1993), and then next to go to the Harmonic theory approach. Within the theory I will analyze the phonological phenomena harmoniously through the important three levels, M-level, W-level, P-level. Therefore this paper is to show that from the comparison between the prosodic analysis and the Harmonic analysis, what is more natural and harmonious analysis is based on the Harmonic approach.

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5kVA 3-level PFC Converter in Thermal Analysis : Comparison of Simulation and Experiment (5kVA 3레벨 PFC 컨버터의 열해석 모의 및 실험적 비교)

  • Lee, Do-Hong;Han, Yu;Choi, Dong-Min;Cho, Younghoon;Choe, Gyu-Ha
    • Proceedings of the KIPE Conference
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    • 2017.07a
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    • pp.359-360
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    • 2017
  • This paper presents comparison of simulation and experiment in thermal analysis of 3-level PFC. Thermal analysis is necessary to optimize the power conversion system to get higher efficiency. Accordingly, analysis via simulation tools and analytic methods is performed to predict the power losses of converter. Consequently, thermal results of 3-level PFC experiment is compared with thermal analysis.

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Effects of Palmijihwangtang (PMT) and Exercise on Glucose Metabolism in Myocardium Cell Membrane and Pancreas $\beta$-Cell of Zucker Diabetic Fatty Rats

  • Lee Myeong-Jong
    • The Journal of Korean Medicine
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    • v.25 no.4
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    • pp.200-208
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    • 2004
  • Objective: Non-insulin Dependent Diabetes Mellitus (NIDDM) is characterized by insulin resistance, which affects the glucose transportation inside the cell. The purpose of this study was to find out how Palmijihwangtang (PMT) and exercise influence the glucose transport metabolism in the organ muscles of ZDF (zucker diabetic fatty) rat with insulin resistance. Methods: Using three male normal zucker rats and twelve male obese rats, they were divided into a normal lean group (N=3), obese control group (N=3), obese exercises group (N=3), obese medication group (N=3), obese exercise and medication group (N=3). Treadmill exercise were repeated with 27m/min speed for an hour a day, five days a week, for 8 weeks. And 20β/sub ¢/ of PMT was orally administered twice a day for 8 weeks, after that a period blood sample was exsanguinated by heart perforation and was analyzed. Results: The body weight of the OM and OEM group showed a significant decrease among all the obese groups. The blood insulin level increased significantly of all groups in comparison with the N group. All of the OE, OM and the OEM groups showed a significant decrease of insulin level compared with the OC group; especially the OEM group demonstrated the most among obese groups. Regarding GLUT-4 level, OEM was the unique group showed a significant increase among all the obese groups. The VAMP-2 level in myocardium cell membrane was increased significantly at OC group in comparison with the N group, whereas the OEM group only showed significant decrease of it. In addition, the VAMP-2 level in pancreas β-cell was significantly decreased at all the obese groups in comparison with the N group. Only the OEM group showed significant increase among all the obese groups. Conclusion: Palmijihwangtang (PMT) and exercise could effectively promote the insulin metabolism in pancreas β-cells and activate the glucose transport process in myocardium cell membrane by lowering the insulin resistance of ZDF rats.

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Is Adjacent Segment Disease More Frequent in Proximal Levels in Comparison with Distal Levels? Based on Radiological Data of at Least 2 Years Follow Up with More than 2 Level Thoracolumbar Fusions

  • Kim, Jung-Ho;Ryu, Dal-Sung;Yoon, Seung-Hwan
    • Journal of Korean Neurosurgical Society
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    • v.62 no.5
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    • pp.603-609
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    • 2019
  • Objective : The purpose of this retrospective study was to determine which of the proximal adjacent segment disease (ASD) and distal ASD was more prevalent and what parameters is more related to ASD in proximal levels and distal levels after more than 2 levels fusions. Methods : The medical records were reviewed retrospectively for 856 cases. A total of 66 cases of ASD were enrolled. On preop magnetic resonance imaging, disc degeneration was measured at the upper and lower parts of surgically treated levels and confirmed by the commonly used Pfirrmann grade. Segmental flexibility in sagittal plane was embodied in segment range of motion (ROM) obtained through flexion and extension X-ray before surgery. Coronal angle was recorded as methods Cobb's angle including fusion levels preoperatively. For the comparison of categorical variables between two independent groups, the chi-square test and Fisher exact test were performed. Results : Proximal ASD and distal ASD were 37/856 (4.32%) and 29/856 (3.39%), respectively. The incidence of proximal ASD was relatively high but insignificant differences. In comparison between ASD group and non ASD group, proximal Pfirmman was higher in proximal ASD and distal Pfirmman was higher in distal ASD group (p=0.005, p<0.008, respectively). However, in the ROM, proximal ROM was higher in proximal ASD, but distal ROM was not different between the two groups (p<0.0001, p=0.995, respectively). Coronal angle was not quite different in both groups (p=0.846). Conclusion : In spite of higher frequency in ASD in proximal level in spinal fusion, it is not clear that incidence of ASD in proximal level is not higher than that of distal ASD group in more than 2 level thoracolumbar fusions. Not only Pfirrmann grade but also proximal segmental ROM is risk factor for predicting the occurrence of ASD in patients more than 2 level of thoracolumbar spine fusion operation excluding L5S1.

A Study on the Effects of Gamisoyosan on Ovariectomized Osteoporosis in Rats (가미소요산(加味逍遙散)이 난소적출로 유발된 흰 쥐의 골다공증에 미치는 영향)

  • Park, Chan-Soo;Sohn, Young-Joo
    • The Journal of Korean Obstetrics and Gynecology
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    • v.21 no.1
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    • pp.1-15
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    • 2008
  • Purpose: Osteoporosis that occurred after menopause is one of the most common metabolic disease. and it is that bone mass significant decrease in comparison with normal people. Its symptoms are fracture, decrease of height, etc. The purpose of this study is to examine what are the effects of the Gamisoyosan on the aged ovariectomized rat model of postmenopausal osteoporosis. Methods: 24 female rats were ovariectomized and divided into normal group(normal), ovariectomized group(control), and treated with Gamisoyosan group(treated). During 8 weeks we dosed D.W to sham and control group, and dosed Gamisoyosan(105 mg/100 g) to experimental group. After 8 weeks we sacrificed rats and measured the body weight, albumin, P, Calcium, ALP, total cholesterol, triglyceride, AST, ALT, T4, estradiol, the femur weight, the tibia ash weight, trabecular bone area, trabecular thickness, osteoclast number. Results: The level of serum albumin, calcium, AST, ALT, estradiol in Gamisoyosan group showed significant increase in comparison with control group. The level of serum triglyceride in Gamisoyosan group showed significant decrease in comparison with control group. Trabecular bone area and osteoclast number in Gamisoyosan group showed significant increase in comparison with control group. Conclusions: Reviewing these experimental results, Gamisoyosan has shown to activate osteogenesis and prevent bone resorption, and it should show efficacy on prevention and improvement of osteoporosis after menopause.

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Radiographic Image and Calcium Metabolism after Experimental Fracture of the Metatarsus in Chicken (병아리 부전골에서 실험적 골절후의 방사선 사진상과 칼슘대사)

  • Lee, Dong-Myoung;Park, Young-Ki
    • Journal of radiological science and technology
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    • v.9 no.1
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    • pp.137-143
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    • 1986
  • This study was undertaken to analyze the changes of radiographical image in avian (chicken) by using scanner and ${\gamma}-camera$ with $Tc^{99m}-MDP$. Experiment was aimed also to observe the changes of calcium, phosphorus and alkaline phosphatase activity in serum after experimental fracture. The results obtained are summerized as follows. 1. 10 chickens grown 6 weeks were scanned within 48 hours after experimental fracture, showed localized increase in uptake. The earlist increased local uptake was observed after 7 hours from experimental fracture at the fracture site. 2. Serum alkaline phosphatase level was increasing continuously during the fracture healing process in comparison with control group and serum alkaline phosphatase activity showed a peak after 2 weeks following the fracture. 3. The change of Ca. amount in serum trended to decrease from 1st day after fracture and it was in the lowest level at the 7 day's group following the fracture. 4. Serum phosphorus level trended to increase after fracture and it was in the highest level at the 7 day's group and showed similar level in comparison with control group.

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A Study on a Conceptual Model for Housing Quality in Urban Area (현대 도시 주거의질(질) 예측을 위한 개념적 모형에 관한 연구 -서울과 대전 지역을 중심으로-)

  • 최목화
    • Journal of the Korean Home Economics Association
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    • v.26 no.2
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    • pp.49-67
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    • 1988
  • The purpose of this study was to present a conceptual model for predicting housing quality. Housing quality was measured in three ways: perceived quality about physical features of houses, perceived level of the quality in comparison with perceived average level I urban area and housing satisfaction. The specific objectives to achieve the purpose were ; 1) to measure the perceived quality about physical features of houses and perceived level of the quality in comparison with the perceived average level I urban 2) to measure the level of housing satisfaction 3) to clarify the causality between the composite variables of housing quality. A final instrument was developed through two stage pilot surveys. The respondents were 1292 homemakers of middle and high economic class in seoul and Daejeon, selected through stratified random sampling technique. Data were collected during March and April, 1986, and analyzed using SPSS and SAS computer packages. The statistics used were frequency, percentage, F-test, Duncan's Multiple Range, x2, Cramer's V, Multiple linear Regression, Path analysis. The major finding were as follows; the variables significantly related to predict the housing quality were found. The simple, composite variables and 3 measures of housing quality were linked using path analysis, thereby a conceptual model predicting housing quality was suggested.

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Benchmarking of the CUPID code to the ASSERT code in a CANDU channel

  • Eun Hyun Ryu;Joo Hwan Park;Yun Je Cho;Dong Hun Lee;Jong Yeob Jung
    • Nuclear Engineering and Technology
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    • v.54 no.11
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    • pp.4338-4347
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    • 2022
  • The CUPID code was developed and is continuously updated in KAERI. Verification and validation (V&V) is mainly done for light water reactors (LWRs). This paper describes a benchmarking of the detailed mesh level compared with sub-channel level for application to pressurized heavy water reactors (PHWRs), even though component scale comparison for the PHWR moderator system was done once before. We completed a sub-channel level comparison between the CUPID code and the ASSERT code and a CUPID code analysis. Because the ASSERT code has already been validated with numerous experiments, benchmarking with the ASSERT code will offer us more trust on the CUPID code. The target channel has high power and thus high pressure deformation. The high power channel tends to have a high possibility of critical heat flux (CHF), because a high void fraction and quality in channel exit region appear. In this research, after determining the reference grid and T/H model, we compared the sub-channel level results of the CUPID code with those of the ASSERT code.