• Title/Summary/Keyword: Combined effect

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Heat Transfer Enhancement by the Combined Effect of Louver Angle and Angle of Attack of Vertex Generator (와류발생기의 충돌각과 루버각의 상호작용에 의한 열전달촉진)

  • 박병규;정재동;이준식
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.14 no.6
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    • pp.477-484
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    • 2002
  • A numerical investigation of the performance of the plate heat exchanger with rectangular winglet is conducted to examine the combined effect of vortex generator and louver fins. Velocity and temperature fields and spanwise averaged Nu and friction factor are presented. Enhancement of heat transfer and flow loss penalty is evident. A Parametric study of three factors (Re, angle of attack and louver angle) with levels of 5 (Re= 300, 500, 700, 900, 1100), 4($\alpha=15^{\circ}, 30^{\circ}, 45^{\circ}, 90^{\circ},$), and 4($\beta=0^{\circ}, 15^{\circ}, 30^{\circ}, 45^{\circ}$), respectively, indicates the performance defined by the ratio of heat transfer enhancement to flow loss penalty shows monotonic behavior for each parameter alone but the interactions between parameters is found to be considerable effect on the performance of heat exchanger and should be considered in design. The effect of stamping is also examined.

Benorylate Interaction with Ethoxybenzamide and Lorazepam (Benorylate와 Ethoxybenzamide 밍 Lorazepam 과의 상호작용)

  • 허인회;이명환
    • YAKHAK HOEJI
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    • v.23 no.1
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    • pp.11-16
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    • 1979
  • Benorylate and ethoxybenzamide have been used alone or in combination as an analgesic, antipyretic and antiinflammatory agent. We investigated the significance of the differences of analgesic activities between single and concurrent administration of benorylate and ethoxybenzamide and lorazepam in mice and also antipyretic activity between single and concurrent administration of benorylate and ethoxybenzamide in rats. 1). Concurrent administration of each half dose of benorylate and ethoxybenamide showed much inhibiting effect on the acetic acid-induced writhing syndrome of mice than the above drug alone, and the some increased analgesic response by hot plate method. 2). The synergistic and analgesic effect of combined administration of benorylate and lorazepam was found to be significant. 3). Antipyretic effect of half-dose combined administration of benorylate and ethoxybenzamide on the rat pyrexia induced by yeast(s.c.) and T.T.G. (i.v.) was shown to be similar to the effect of each drug.

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Meta-Analysis on the Effectiveness of Interventions Applied to Preventing Endotracheal Suction-Induced Hypoxemia (기관내 흡인으로 인한 저산소증 예방을 위한 중재 효과에 대한 메타분석)

  • 오현수
    • Journal of Korean Academy of Nursing
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    • v.33 no.1
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    • pp.42-50
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    • 2003
  • Purpose: This study was conducted to investigate the effects of the suction-induced hypoxemia interventions. Method: 30 suction-induced hypoxemia interventions were reviewed for the purpose of meta-analysis. Result: The study showed that both preoxygenation and insufflation were the most frequently examined oxygenation time periods, and hyperoxygenation combined with hyperinflation was the most commonly applied oxygenation method in order to prevent suction-induced hypoxemia. The greatest effect was obtained by providing oxygenation before and after suctioning, whereas negative effect(the contrary results from the study hypotheses) was frequently obtained by applying insufflation only. Applying hyperoxygenation combined with hyperinflation had the greatest effect over that of applying hyperoxygenation only, even though the difference between effect sizes of both methods were statistically significant. Conclusion: The results of meta-analysis showed that the occurrence rate of hypoxemia after suctioning was significantly reduced with the overall interventions for hypoxemia (decreasing 40% of occurrence rate), independent with time periods or methods for providing oxygenation.

Studies on the Efficacy of Combined Preparations of Crude Drugs (IV) -Effect of ‘Whangryonhaedok-Tang’ on the Central Nervous System- (생약복합제(生藥複合劑)의 약효연구(藥效硏究) 제4보(第4報) -황연해독탕(黃連解毒湯)의 중추신경계(中樞神經系) 작용(作用)에 대(對)하여-)

  • Hong, N.D.;Kim, J.W.;Doo, H.K.;Kim, N.J.
    • Korean Journal of Pharmacognosy
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    • v.13 no.1
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    • pp.20-25
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    • 1982
  • In order to investigate the pharmacological action of combined preparation of crude drugs, 'Whangryonhaedok-Tang' were studied. Pharmacological studies of the water extract, methanol insoluble fraction and methanol soluble fraction obtained from 'Whangryonhaedok-Tang' were conducted. The results of this investigation were summarized as follows; Central convulsions induced by strychnine, picrotoxine and caffeine were depressed in mice. Analgesic effect was observed in mice and rats. Antipyretic effect was observed in rats and rabbits. Sedative effect was observed.

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Copper Particle Effect on the Breakdown Strength of Insulating Oil at Combined AC and DC Voltage

  • Wang, You-Yuan;Li, Yuan-Long;Wei, Chao;Zhang, Jing;Li, Xi
    • Journal of Electrical Engineering and Technology
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    • v.12 no.2
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    • pp.865-873
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    • 2017
  • Converter transformer is the key equipment of high voltage direct current transmission system. The solid suspending particles originating from the process of installation and operation of converter transformer have significant influence on the insulation performance of transformer oil, especially in presence of DC component in applied voltage. Under high electric field, the particles easily lead to partial discharge and breakdown of insulating oil. This paper investigated copper particle effect on the breakdown voltage of transformer oil at combined AC and DC voltage. A simulation model with single copper particle was established to interpret the particle effect on the breakdown strength of insulating oil. The experimental and simulation results showed that the particles distort the electric field. The breakdown voltage of insulating oil contaminated with copper particle decreases with the increase of particle number, and the breakdown voltage and the logarithm of particle number approximately satisfy the linear relationship. With the increase of the DC component in applied voltage, the breakdown voltage of contaminated insulating oil decreases. The simulation results show that the particle collides with the electrode more frequently with more DC component contained in the applied voltage, which will trigger more discharge and decrease the breakdown voltage of insulating oil.

Enhanced Susceptibility of Human Squamous Cell Carcinoma to Photodynamic Therapy Combined with Administration of Cisplatin

  • Ahn, Jin-Chul;Chung, Pil-Sang;Park, Byung-Kuhn
    • Biomedical Science Letters
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    • v.14 no.2
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    • pp.83-89
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    • 2008
  • We have compared the antitumor effect of photodynamic therapy (PDT), using 5-aminolevulinic acid (ALA) as the photosensitizer, combined with cisplatin (CDDP) on AMC-HN3 human squamous cell carcinoma. AMC-HN3 cells were cultured and then incubated with various concentrations of CDDP and ALA. 632 nm diode laser was given at $6.0J/cm^2$ followed by incubation for 24 hours. The evaluation of cell viability was done by MTT assay. In vivo CDDP was injected intraperitoneally 24 hours prior to PDT. The anti-tumor effects of each treatment were measured by tumor volume change. Cell viability were 44.29% for the cisplatin-mediated chemotherapy group $(6.25{\mu}g/ml)$, 77.22% for ALA-PDT group, and 15.06% for the Combination therapy group. In vivo, the antitumor effect of photodynamic therapy was enhanced by combination of Cisplatin-mediated chemotherapy. Photodynamic therapy combined with administration of Cisplatin appears to enhance antitumor effect and to be a useful treatment modality.

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Efficiency of Combined Action of Moxalactam and Fosfomycin Determined by MS-2 System Against Penicillin-resistant Staphylococcus aureus Isolates (MS-2 system을 이용한 황색포도구균에 대한 moxalactam과 fosfomycin의 병용효과 측정)

  • Park, Chan-Sok;Ahn, Tai-Hew
    • The Journal of the Korean Society for Microbiology
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    • v.21 no.3
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    • pp.381-385
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    • 1986
  • Twenty strains of penicillin(PC)-resistant Staphylococcus aureus ($MIC{\geqq}32U/ml$) were chosen randomly from recent isolates and submitted to the present experiment to see what effect the combined antibiotic action of moxalactam(MX) and fosfomycin(FM) would bring about on the cells, using MS-2 system. 1. The conventional agar dilution method and the rapid automatic MS-2 system were used in measuring the MICs of MX and FM against each strain and the comparison of the data obtained revealed no significant difference between the two methods in the titer and distribution of the MICs. 2. The automatic MS-2 system was, therefore, used alone in determining the combined growth inhibitory effect of MX and FM because of its more rapidness, and the obtained results were that most of the PC-resistant strains(16 out of 20, 80%) were synergistically inhibited by the two antibiotic combination while additive effect was observed in the remaining 4 strains(20%). 3. Thus, it is suggested that the growth of PC-resistant staphylococcal cells may be synergistically inhibited by MX and FM combination and the efficiency of two antibiotic action as well as MIC of single antibiotic may be more rapidly determined by the MS-2 system than by the conventional method.

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Case Study of Western-Oriental Medication Combination Treatment for Helicobacter pylori Infection (헬리코박터 파일로리 감염의 한.양약 병용치료 효과 및 안전성에 관한 증례 보고)

  • Bae, Su-Hyun;Park, Seon-Young;Jin, Myung-Ho;Park, Sang-Eun;Hong, Sang-Hoon
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.26 no.3
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    • pp.381-385
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    • 2012
  • We investigated the eradication rate and the adverse effects of combined treatment with western and oriental medication on Helicobacter pylori infected patients. We studied the eradication rate and the adverse effects of 1-week-triple therapy and 2-week-oriental medication(Banhasasimtang or Hyangsapeungeuysan) on Helicobacter pylori infected patients confirmed by urea breath test. Comparing 5 patients who took combined treatment with western and oriental medication, the results of this study showed that 4 patients got eradication effect of Helicobacter pylori with no influence on liver and kidney function. A patient had diarrhea and another patient had satiety after meals because of an adverse effect. Despite some possitive effect, the treatment did not make the Quality of Life improved. The findings of this study supports the adverse effects of combined treatment with western and oriental medication for the treatment of Helicobacter pylori infection.

The Effect of Headaches and Quality of Life with the Combined Western-Oriental Medicine Massage Program for Chronic Headache Patients (양.한방 혼합 마사지요법이 만성두통 환자의 두통 및 삶의 질에 미치는 효과)

  • Kim, Jung-Soon;Kim, Myoung-Soo;Lee, Sang-Ju
    • Korean Journal of Adult Nursing
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    • v.23 no.2
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    • pp.170-179
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    • 2011
  • Purpose: The purpose of this study was to identify the effect of combined Western and Oriental medicine headache massage program for chronic headache patients. Methods: This study was designed using the Nonequivalent control group pretest-posttest design. The forty nine patients were divided into an experimental group (25 patients) and a control group (24 patients). Collected data were analyzed by Chi-test, t-test, Fisher's exact test, Repeated measures ANOVA using SPSS/WIN 14.0 program. Results: After treatment in this program, the experimental group had no significan difference in scores for headache intensity and frequency as the length of time in treatment increased compared to the control group. But there were significant decreases in the use of medication (F=4.209, p=.046) and disturbances in the quality of life related to headaches (F=13.097, p=.001) after providing the combined Western-Oriental massage program. Conclusion: This program could have a positive effect on using medication for pain controllers and headache related quality of life. Based on the results of this study, further research focusing on the effectiveness of unique nursing intervention for chronic headache patients is suggested.

A Novel Scheme to Mitigate a GPS L1 C/A Signal Repeat-back Jamming Effect, According to a Code Tracking Bias Estimation, Using Combined Pseudo-random Noise Signals (통합 의사잡음신호 기반 부호추적편이 추정에 따른 GPS L1 C/A 신호의 재방송재밍 영향 완화 기법)

  • Yoo, Seungsoo;Yeom, Dong-Jin;Jee, Gyu-In;Kim, Sun Yong
    • Journal of Institute of Control, Robotics and Systems
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    • v.22 no.10
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    • pp.869-875
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    • 2016
  • In this paper, a novel scheme with which to mitigate a repeat-back jamming effect is proposed for the GPS L1 coarse/acquisition signal. The proposed scheme estimates the code tracking bias caused by repeat-back jamming signals using a Combined Pseudo-random noise signal. It then mitigates the repeat-back jamming effect by subtracting the estimated code timing on a normal correlation channel from the estimated value. Through a Monte-Carlo simulation, the proposed scheme can diminish the running average of code tracking bias to less than 10% of the bias using the conventional scheme.