• 제목/요약/키워드: Controlled study

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시뮬레이션을 이용한 작업자/복수기계 가동분석에 대한 사례연구 (A Case Study on the Analysis of Man/Multi-Machine System Using Simulation)

  • 문덕희;송성;최미진;정종윤
    • 한국시뮬레이션학회논문지
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    • 제12권1호
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    • pp.21-34
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    • 2003
  • This paper deals with a case study of workload analysis of an operator in an automatic line for machining the race of ball bearing. Eleven machines and three hoppers are installed in the line which is operated by an operator. The elements of operation are separated into machine controlled elements, operator controlled elements and machine/operator controlled elements. In order to analyze the system, time and motion studies are used for gathering input data for the simulation model. The first objective of this study is to evaluate whether the workload of operator is reasonable or not. The second objective is to increase throughput by reducing tact time and the last one is to increase frequencies of inspection by reducing interval. Thus we suggest some ideas for improvement, and as a result, the throughput is improved about 9%. In spite of the increasing of throughput, the allowance of operator is also increased about 4%.

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가미귀비탕(加味歸脾湯)이 백서(白鼠)의 배란(排卵)에 미치는 영향(影響) (Effects of Gamiguibitang on the ovulation in rats)

  • 최창민;홍기철;김덕님;김송백;유심근
    • 대한한의학방제학회지
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    • 제11권2호
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    • pp.111-124
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    • 2003
  • Gamiguibitang(GMGBT) is used in amenorrhea and female infertility caused by ovulation disorder. An attempt was made to evaluate the influences of GMGBT on the serum concentrations of FSH, LH, estradiol(E2) and progesterone, the histological and optical changes of ovary of rats. The results of the study were as follows: 1. Blood FSH level significantly increased in experimental group controlled by four times quantity as compared with control group. 2. Blood LH level increased in experimental group controlled by four times quantity as compared with control group, which showed no efficacy. 3. Blood E2 level increased in experimental group controlled by four times quantity as compared with control group, which showed no efficacy. 4. Blood progesterone level significantly decreased in experimental group controlled by double quantity as compared with control group. 5. In optically observations of ovary, weight of ovary significantly increased in experimental group controlled by double quantity as compared with control group 6. In histological observations of ovary, ovulation significantly increased in experimental group controlled by both double and four times quantity as compared with control group. According to these results, it can be concluded that GMGBT influences the pituitary gland and ovary to increase the ovulation of rats.

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Development of Controlled Release Oral Drug Delivery System by Membrane-Coating Method-I - Preparation and pharmaceutical evaluation of controlled release acetaminophen tablets-

  • Shim, Chang-Koo;Kim, Ki-Man;Kim, Young-Il;Kim, Chong-Kook
    • Archives of Pharmacal Research
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    • 제13권2호
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    • pp.151-160
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    • 1990
  • In order to develop a controlled-release oral drug delivery system (DDS) which sustains the plasma acetaminophen (AAP) concentration for a certain period of time, microporous membrane-coated tablets were prepared and evaluated in vitro. Firstly, highly water-soluble core tablet of AAP were prepared with various formulations by wet granulation and compression technique. Then the core tablets were coated with polyvinychloride (PVC) in which micronized sucrose particles were dispersed. Effect of formula compositions of core tablets and coating suspensions on the pharmaceutical characteristics such as drug release kinetics and membrane stability of the coated tablets was investigated in vitro. AAP was released from the coated tablets as a zero-order rate in a pH-independent manner. This independency of AAP release to pH change from 1.2 to 7.2 is favorable for the controlled oral drug delivery, since it will produce a constant drug release in the stomach and intestine regardless of the pH change in the GI tract. Drug release could be extended upto 10 h according to the coating condition. The release rate could be controlled by changing the formula compositions of the core tablets and coating suspensions, coat weight per each tablet, and especially PVC/sucrose ratio and particle size of the sucrose in the coating suspension. The coated tablets prepared in this study had a fairly good pharmaceutical characteristics in vitro, however, overall evaluation of the coated tablet should await in vivo absorption study in man.

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황련해독탕약침 치료에 대한 임상 논문 고찰: 국내 학술지의 증례보고와 대조군 연구 중심으로 (An Intensive Review On Clinical Thesis about Hwangryunhaedok-tang Pharmacopuncture Treatment: Focused on Case Reports and Controlled Studies in Korean Academic Journals)

  • 이수환;김순중
    • 한방재활의학과학회지
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    • 제29권2호
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    • pp.171-188
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    • 2019
  • Objectives The purpose of this thesis is to compare and analyze outcomes of case studies and controlled studies about Hwangryunhaedok-tang (HHT) pharmacopuncture in clinical studies. Based on these studies reporting clinical effects by using HHT pharmacopuncture, we object to deduct the comparative review in applying clinical disorders limitedly. And conclusionally, by using this comparative review, we aim to make the fine evidence in treating clinical specific diseases. Methods We searched 106 studies about HHT pharmacopuncture from 6 Korean web databases by using in Korean word 'Hwangryunhaedok-tang pharmacopuncture'. This search had been progressed throughout 1 month (January, 2019). There was 106 thesis and we excluded studies that are not related to HHT pharmacopuncture, experimental research, not the case report or randomized controlled trials, non-randomized controlled trials, not using HHT pharmacopuncture, not using only one pharmacopuncture, and not using HHT pharmacopuncture for major treating method. As a result, 39 thesis are selected as a population. Results We analyzed 34 case reports and 5 controlled studies. As the final outcome, HHT pharmacopuncture was used in musculoskeletal diseases, dermatopathy, and 32 specific diseases. Conclusions After analyzing 39 studies, effective symptom changes clinically and statistically by using HHT pharmacopuncture herbal acupuncture were identified. However, these thesis designs were reported deficiently in many parts such as not excluding other confounding variables. After modifying defects of thesis design and conduct study, it can play a role as the evidence using HHT pharmacopuncture more precisely.

호흡조절에 따른 위전도와 심박변이도 변화 연구 (The Study on the Change of EGG and HRV through Respiratory Control)

  • 하성룡;박영배;양동훈;박영재;김민용
    • 대한한의진단학회지
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    • 제11권1호
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    • pp.157-166
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    • 2007
  • Background: The change in the respiratory pattern has an influence on the change in the autonomic nervous system, which in turn has an influence on the EGG to measure a gastric activity. However, the study on the influence on the EGG parameters by respiratory control and on the correlation between the HRV and EGG through respiratory control has not been perform yet. Objective: It is to perform a series of experiments to find out how the EGG parameters are influenced by the controlled respiration and what correlation there may exist between the EGG and HRV to measure the change in the autonomic nervous system after controlled respiration. Methods: 1st Experiment: During a 15minutes' voluntary respiration, HRV was measured, and it was measured again during another 15 minutes' controlled respiration. 2nd Experiment: After an eight hours' fast, EGG was measured for a period of 30 minutes, and then after another 15 minutes' voluntary respiration, a test-meal was offered for 10 minutes and again EGG was measured. The next day, after an 8 hour's fast, EGG was measured for 30 minutes, and after a 15 minutes' controlled respiration and offered with a test-meal for 10 minutes and then EGG was measured again for 30 minutes. Results: 1. It was observed in all the channels that the power ratio increased more after controlled respiration than after voluntary respiration. No statistical significance, however, could be observed. 2. Through controlled respiration, the HF of HRV and the power ratio of EGG Channel 4 was negatively correlated, while the LF/HF of HRV and the power ratio of EGG channel 1 & 4 was positive correlated. Such correlations as mentioned above, however, could not be observed in HRV & EGG through voluntary respiration. Conclusions: 1. It was concluded that the increase in the power of gastric contractile after controlled respiration is bigger than the increase in the power of gastric contractile after voluntary respiration. 2. It was concluded that the gastric contractile power and sympathetic activity through controlled respiration was negatively correlated, while the gastric contractile power and parasympathetic activity through controlled respiration was positively correlated.

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시효영향에 따른 304스테인리스강의저 사이클 피로 거동에 관한 연구 (A Study on the Low-Cycle Fatigue Behavior for Thermally-Aged 304 Stainless Steel)

  • 백남주;이상매;이민우
    • 한국정밀공학회지
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    • 제4권1호
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    • pp.53-64
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    • 1987
  • Low Cycle fatigue data through stress controlled and strain controlled tests at room temperature were obtained for solution treated and thermally aged 304 stainless steel. All the tests were conducted with the greguency, 1Hz of stress controlled and the strain rate, 40%/min of strain controlled. The aged specimen had the longer fatigue life at the lower stresses than at the higher stresses. It is shown that the fatigue limit of the aged specimen was a little higher than that of the solution treated specimen. It is considered to be due to the presence of carbide precipitates at grain boundary which depressed the crack propagation. The aged specimen showed the larger alternating stress and the more rapid cyclic work harding than the solution treated specimen. Bauschinger effect of the aged specimen was not pronounced than that of the solution treated specimen.

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분자동력학을 이용한 결정립 제어 레오로지 소재의 나노 변형거동 전산모사 (Molecular Dynamics Simulation of Nano-Deformation Behavior of the Grain-Size Controlled Rheology Material)

  • 김정원;윤성원;강충길
    • 소성∙가공
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    • 제14권4호
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    • pp.319-326
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    • 2005
  • In this study, the nano-deformation behavior of semi-solid Al-Si alloy was investigated using a molecular dynamics simulation as a part of the research on the surface crack behavior in thixoformed automobile parts. The microstructure of the grain-size controlled Al-Si alloy consists of primary and eutectic regions. In eutectic regions the crack initiation begins with initial fracture of the eutectic silicon particles and inside other intermetallic phases. Nano-deformation characteristics in the eutectic and primary phase of the grain-size controlled Al-Si alloy were investigated through the molecular dynamics simulation. The primary phase was assumed to be single crystal aluminum. It was shown that the vacancy occurred at the zone where silicon molecules were.

단독 경막외 통증자가조절법과 지속주입을 병용한 경막외 통증자가조절법의 비교 (Comparison of Patient Controlled Epidural Analgesia Alone and Patient Controlled Epidural Analgesia with Continuous Infusion)

  • 김동희;이태수
    • The Korean Journal of Pain
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    • 제9권2호
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    • pp.368-373
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    • 1996
  • Background: The purpose of this study was to determine whether there is any advantage for a continuous background infusion during patient controlled epidural analgesia(PCEA) for postoperative pain control. Methods: 60 patients scheduled for elective cesarean section under epidural anesthesia were assigned randomly in a double-blind fashion to receive fentanyl and bupivacaine by PCEA with or without background infusion for 48 hours postoperatively. Results: Total amount of fentanyl and bupivacaine consumption and degree of sedation were not significantly different between the two groups. Visual analogue scale(VAS) pain scores at 24, 36, and 48h and sleep disturbance were significantly lower in background infusion group. Conclusion: Administration of fentanyl with bupivacaine by continuous background infusion is appropriate for PCEA for postcesarean section pain control.

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안드로이드 스마트폰 제어기반의 개인용 탑승로봇 구현 (Development of a Personal Riding Robot Controlled by a Smartphone Based on Android OS)

  • 김연균;김동헌
    • 제어로봇시스템학회논문지
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    • 제19권7호
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    • pp.592-598
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    • 2013
  • In this paper, a small, lightweight smartphone-controlled riding robot is developed. Also, in this study, a smartphone with a jog shuttle mode for consideration of user convenience is proposed to make a small, lightweight riding robot. As well, a compass sensor is used to compensate for the mechanical characteristics of motors mounted on the riding robot. The riding robot is controlled by the interface of a drag-based jog shuttle in the smartphone, instead of a mechanical controller. For a personal riding robot, if the smartphone is used as a controller instead of a handle or a pole, it reduces its size, weight, and cost to a great extent. Thus, the riding robot can be used in indoor spaces such as offices for moving or a train or bus station and an airport for scouting, or hospital for disabilities. Experimental results show that the riding robot is easily and conveniently controlled by the proposed smartphone interface based on Android.

제어자발화 가솔린기관의 성능 특성 (Performance Characteristics of a Controlled Auto-Ignition Gasoline Engine)

  • 김홍성
    • 한국기계가공학회지
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    • 제4권1호
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    • pp.56-62
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    • 2005
  • In this study, A controlled auto-ignition (CAI) single cylinder gasoline engine is considered, focusing on the extension of operating conditions. The fuel is injected indirectly into electrically heated inlet air flow. Investigated are the engine performance characteristics under the wide range of operating conditions such as 32 to 63 in the air-fuel ratio, 1000 to 1800 rpm in the engine speed, and 150 to $180^{\circ}C$ in the inlet-air temperature. A controlled auto-ignition gasoline engine which has the super ultra lean-burn with self-ignition of gasoline fuel can be achieved by heating inlet air.

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