• Title/Summary/Keyword: difference system

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A NUMERICAL METHOD FOR SINGULARLY PERTURBED SYSTEM OF SECOND ORDER ORDINARY DIFFERENTIAL EQUATIONS OF CONVECTION DIFFUSION TYPE WITH A DISCONTINUOUS SOURCE TERM

  • Tamilselvan, A.;Ramanujam, N.
    • Journal of applied mathematics & informatics
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    • v.27 no.5_6
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    • pp.1279-1292
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    • 2009
  • In this paper, a numerical method that uses standard finite difference scheme defined on Shishkin mesh for a weakly coupled system of two singularly perturbed convection-diffusion second order ordinary differential equations with a discontinuous source term is presented. An error estimate is derived to show that the method is uniformly convergent with respect to the singular perturbation parameter. Numerical results are presented to illustrate the theoretical results.

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A Study on Natural Convection from Two Cylinders in a Cavity

  • Mochimaru Yoshihiro;Bae Myung-Whan
    • Journal of Mechanical Science and Technology
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    • v.20 no.10
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    • pp.1773-1778
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    • 2006
  • Steady-state natural convection heat transfer characteristics from cylinders in a multiply-connected bounded region are clarified. A spectral finite difference scheme (spectral decomposition of the system of partial differential equations, semi-implicit time integration) is applied in numerical analysis, with a boundary-fitted conformal coordinate system through a Jacobian elliptic function with a successive transformation to formulate a system of governing equations in terms of a stream function, vorticity and temperature. Multiplicity of the domain is expressed explicitly.

Image Comparative Evaluation by PET/CT Equipment Using Phantom (팬텀을 활용한 PET/CT 장비 별 영상 비교 평가)

  • Moo-Jin Jeong;Jun-Chul Ham;Yong-Hoon Choi;Young-Kag Bahn;Han-Sang Lim;Jae-Sam Kim
    • The Korean Journal of Nuclear Medicine Technology
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    • v.28 no.1
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    • pp.71-79
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    • 2024
  • Purpose: This study aims to identify SUV, SNR, spatial resolution, and axial uniformity under the same reconstruction conditions and to find out the differences between equipment models. Materials and Methods: The equipment was GE's Discovery 600, 710, IQ, MI(GE Healthcare, USA), and the Phantom used ACR(American College of Radiology) Flangeless Esser Phantom and PET/SPECT Performance Phantom. The PET/SPECT Performance Phantom injected 18F-FDG at a concentration of 3.8 kBq/mL, and the ACR Flangeless Esser Phantom made the conditions for Hot Spot and Background activity for 4 : 1. Image evaluation was compared and evaluated for SUV, SNR, spatial resolution, and axial uniformity with the same reconstruction that added SharpIR of VPHD. Results: The SUVmax showed a difference up to 4.6% with an average of 2.71, 2.35, 1.89, and 1.43 from Hot Spot 1 to 4, and the SUVmean showed a difference up to 4.7% with 2.06, 1.75, 1.49, and 1.27. There was a difference up to 5% between equipment, and there was no significant difference between both SUVmax and SUVmean. SNR showed a difference up to 0.04 with an average of 0.37, 0.26, 0.18, and 0.11. FWHM showed a difference up to 0.27. Lastly, COV of axial uniformity was up to 0.018. Conclusion: SUV showed differences within 5% between equipment and showed no significant difference. This is considered to be used as basic data that can be used for the development and replacement of equipment because it has the advantage of being able to observe with a large number of equipment.

Unmanned Patient Monitoring System Using Frame Difference Method and Decibel Threshold (프레임 차이법과 데시벨 임계치를 이용한 무인 환자 감시 시스템)

  • Lee, Kee-Woo;Lee, Hyuk-Soo
    • Journal of the Institute of Convergence Signal Processing
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    • v.8 no.1
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    • pp.1-5
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    • 2007
  • In this paper, we propose an unmanned patient monitoring system design and performance of a motion capture and sound detection. Unmanned patient monitoring system can be used in the greek koma and meaning deep sleep patient to need 24 hour surveillance. To monitoring, we used laptop, CCTV camera (or PC camera), A/D converter, microphone and detection program. The detection program based on the frame difference method and sound level meter. It had several functions such as data collecting and storing. All of this system was tested in several the simulations of emergency situations. It can be expected that an unmanned patient monitoring system can be used in emergency situation and patient care.

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Effects of Diagnosis-Related Group-Based Payment System on the Risk-Adjusted Cesarean Section Rate (Diagnosis-Related Group 지불제도가 위험도 보정 제왕절개 분만율에 미치는 영향)

  • Kwak, Jin-Mi;Lee, Kwang-Soo
    • Health Policy and Management
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    • v.31 no.2
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    • pp.180-187
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    • 2021
  • Background: This study analyzed the effect of applying the diagnosis-related group (DRG)-based payment system, which was implemented in July 2012 for hospitals and clinics nationwide, on the cesarean section rate. Methods: The subjects of the study were divided into new groups that participated in the payment system after July 2012 and maintenance groups that participated in the payment system before July 2012. As an analysis method, a difference-in-difference analysis, which is a quasi-experimental design, was used. The risk-adjusted cesarean section rate was used as a dependent variable. Results: Seven risk factors (malpresentation of fetus, eclampsia, multiple pregnancies, problems in the placenta, previous Cesarean section, cephalopelvic disproportion, problems in amniotic fluid) were included in the final risk-adjustment model, and found to have a statistically significant relationship with the cesarean section rate. Results showed that the risk-adjusted cesarean section rate increased significantly in new groups after the application of the DRG-based payment system. Conclusion: Study results provided policy implications for the reorganization of the DRG-based system should that reflects the demands of obstetricians, such as organizing a consultative body with obstetricians and establishing a reasonable fee.

The Change of Mu Rhythm according to Familiarity of Observation Stimulus in Stroke Patients (관찰 자극의 친숙도에 따른 뇌졸중 환자의 뮤리듬 변화)

  • Yun, Tae-Won;Lee, Moon-Kyu
    • PNF and Movement
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    • v.9 no.4
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    • pp.33-40
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    • 2011
  • Purpose : The aims of this study was to identify changes mu rhythm according to familiarity with a stimulus in people with stroke. Methods : Seventeen right-handed participants were asked to observe 2 different stimulus; a non-familiarity stimulus condition (NFSC), and a familiarity stimulus condition (FSC). Electroencephalogram (EEG) signals from electrodes on the participant's scalp were recorded during action observation. The activation of the mirror neuron system was compaired between FSC and NFSC by a paired t-test. An independent t-test was used to compare the difference between right and left hemispheres for the activation of the mirror neuron system during action observation of performing a task with the right hand. Results : The result of paired t-test showed no significantly difference between NFSC and FSC in the activation of the mirror neuron system. The Result of independent t-test also showed no significantly difference in the activation of mirror neuron system between the right and left hemispheres. Conclusion : The familiarity with a stimulus had no signigicant effect on the activation of the mirror neuron system according to the familiarity and in either the right or left hemispheres in people with chronic stroke.

Color Culture of Japanese Modern Age -Focussed on Edo Period- (일본 근세의 색채 문화 -에도(江戶) 시대를 중심으로-)

  • Lee, Kyunghee
    • Journal of Fashion Business
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    • v.20 no.4
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    • pp.1-14
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    • 2016
  • Japan has several unique traditional colors. The traditional colors of Japan include a collection of colors used in traditional Japanese literature, textiles such as the kimono, and other Japanese arts. Japanese color system has a long history, leading to some consistencies in color and naming. During the Edo period(1603~1867), the unique color sense of 'iki' produced many color names that are often related to mouse(nezumi) and tea(cha), and fashion color originated as kabuki actors. As for colors named after animals, the most popular appears to be the mouse, which is used to express grey tones. Recently, many fashion companies in Japan have been working on reviving an interest in traditional Japanese colors. Ordinary people of Edo named even slightly different color tones, each with individual exquisite and mind valuing 'iki' senses. They translated these into their livelihood and culture. The colorimetry result of 49 restored dyed fabrics were as follows; Hue difference was 7.8, value difference was 2.9, chroma difference was 1.8 of prefix siro. Hue difference was 3.8, value difference was 1.6, chroma difference was 1.7 of prefix usu. Hue difference was 3.5, value difference was 1.5, chroma difference was 1.4 of prefix cha. Hue difference was 6.4, value difference was 1.1, chroma difference was 1.6 of prefix koi. Hue difference was 7.5, value difference was 0.8, chroma difference was 3.3 of prefix nezumi.

Investigation Study on Gender Difference Based on Korean Data Related to Drug Use (의약품 사용 관련 국내 통계자료에 나타난 성별 차이 조사 연구)

  • Rhee, Su-Jin;Lee, Byung-Yo;Kwon, Kwang-Il
    • Korean Journal of Clinical Pharmacy
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    • v.23 no.2
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    • pp.114-122
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    • 2013
  • Background: Drugs should be evaluated in appropriate subjects representing potential population to take the drugs. This study focuses on gender factor and aims to make known the appropriateness of considering gender difference on clinical evaluation of drug with domestic data related to drug use. Methods: To understand gender difference shown in drug use, three types of domestic statistical data (prevalence of chronic disease, number of outpatient with major concerning disease, and consumption of medicine) were analyzed and compared according to gender. Results: Three of fifteen chronic diseases which were analyzed, showed significantly higher prevalence in women than in men, and three were vice versa. Meanwhile, the sex ratio of outpatients was significantly different in 22 major concerning diseases. Among the drug groups coded by Anatomical Therapeutic Chemical (ATC) Classification System, the consumption of most drug groups was generally higher in women than in men except for one group coded G (genito-urinary system and sex hormones). Conclusion: Gender difference should be considered in domestic clinical evaluation of drug and domestic guidance for reflecting gender difference should be established.

Comparative Performance Analysis of Pressurized Solid Oxide Fuel Cell / Gas Turbine Hybrid Systems Considering Different Cell Inlet Preheating Methods (셀 입구 예열방법에 따른 가압형 고체산화물 연료전지/가스터빈 하이브리드 시스템의 성능 비교 해석)

  • Yang Won Jun;Kim Jae Hwan;Kim Tong Seop
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.29 no.6 s.237
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    • pp.722-729
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    • 2005
  • Design analysis of the solid oxide fuel cell and gas turbine combined power system is performed considering different methods for preheating cell inlet air. The purpose of air preheating is to keep the temperature difference between cell inlet and outlet within a practical design range thus to reduce thermal stress inside the cell. Three different methods considered are (1) adopting a burner in front of the cell, (2) adopting a preheater (heat transfer from the main combustor) in front of the cell and (3) using recirculation of the cathode exit gas. For each configuration, analyses are carried out for two values of allowable maximum cell temperature difference. Performance characteristics of all cases are compared and design limitations are discussed. Relaxation of the cell temperature difference (larger difference) is proved to ensure higher efficiency. Recirculation of the cathode exit gas exhibits better performance than other methods and this advantage becomes more prominent as the constraint of the cell temperature difference becomes more severe (smaller temperature difference).

A study on Learning Motivation and Career Preference After Graduation of University Students Majoring in Physical Therapy (물리치료 전공대학생들의 진로선호도와 학습동기에 관한 연구)

  • Kang, Jun-Gu;Bok, Won-Ju;Seo, You-Ri;Lee, Do-Young;Han, Dong-Guk;Son, Kyung-Hyun;Lee, Kyung-Hyun
    • Journal of Korean Physical Therapy Science
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    • v.22 no.2
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    • pp.19-27
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    • 2015
  • Purpose : This study is to investigate on career preference after graduation and learning motivation of students majoring in physical therapy. Methods : This survey implement with 400 students majoring in physical therapy from 3 college and university in korea, jeonnam 394 of 400 attended this survey. The measured date were analysed by using repeated anova, frequency analysis, $x^2$-test, t-test. Results : The results of this study were as follows: Career preference showed significant difference between male and female in department of orthopedic physical therapy and showed significant difference all by workplace(general hospital, special hospital). Career preference didn't show significant difference by schol system(college, university) and showed significant difference by work place. Learning motivation(inner motivation) showed significant difference in male by gender. Learning motivation didn't show significant difference by school system.

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