• Title/Summary/Keyword: case-controlled study

Search Result 1,015, Processing Time 0.029 seconds

A STUDY ON THE REACTIVE POWER COMPENSATION OF THREE PHASE UNBALANCED LOAD FOR VAR SYSTEM (VAR 시스템에 의한 3 상 불평형 부하의 무효전력 보상에 관한 연구)

  • Jung, Yon-Taek;Seo, Young-Soo;Kim, Young-Bong;Kim, Han-Soo;Lee, Bong-Joo
    • Proceedings of the KIEE Conference
    • /
    • 1989.07a
    • /
    • pp.531-534
    • /
    • 1989
  • In this paper, the way that input voltage and input line current as a control variable is provided as one unit is projected. Till no, have denied with three phase balanced load. But, in that case, total power factor compensation is difficult, for to control each phase at unbalanced load. Therefor, in this paper suggest of the scheme that three phase unbalanced load is controlled by each phase and input total power factor is compensated unit input factor. therefore, in this paper suggest that three phase unbalanced load is controlled and the method in compensation of unit input factor to be attended by unbalanced load. Besides, the object of control is calculating quantity for input voltage and input line current for the point at issuse make to improve of control method at unbalanced load. As a result, control system of each phase could maintain as a unit input total power factor has been state diviation error of 2% with unbalanced load.

  • PDF

The Study of Correlation between Objective Human Response and Subjective Discomfort Evaluation of Idle Vibration on Passenger Vehicle (승용차량 정차시 발생하는 진동에 대한 객관적 인체반응특성과 주관적 불편함평가의 상관성에 관한 연구)

  • Lee, Jae-Young;Jeon, Gyeoun-Jin;Ahn, Se-Jin;Jeong, Weui-Bong
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2012.04a
    • /
    • pp.455-460
    • /
    • 2012
  • Thirteen taxi drivers as the subject in the experiment were exposed to vertical vibration which is controlled on a rigid seat reflecting vibration on passenger vehicle. They were employed not only to get human response of objective measurement but also to make subjective evaluation of the vibration. The subjective evaluation was estimated using the absolute discomfort threshold of the controlled vibration, which was achieved with the three-down one-up method that is widely used in the field of psychophysics. As the result, apparent mass and apparent eccentric mass as objective human response tend to gradually decrease when frequency of the vibration increases. The absolute discomfort threshold was increased in case of increasing the frequency. Concludingly, the subjective discomfort evaluation is highly correlated with the objective human responses at the range of idle vibration on passenger vehicle.

  • PDF

The Study of Correlation between Objective Human Response and Subjective Discomfort Evaluation of Idle Vibration on Passenger Vehicle (승용차량 정차시 발생하는 진동에 대한 객관적 인체반응특성과 주관적 불편함평가의 상관성에 관한 연구)

  • Lee, Jae-Young;Jeon, Gyeoung-Jin;Ahn, Se-Jin;Jeong, Weui-Bong
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.22 no.5
    • /
    • pp.422-428
    • /
    • 2012
  • Thirteen taxi drivers as the subject in the experiment were exposed to vertical vibration which is controlled on a rigid seat reflecting vibration on passenger vehicle. They were employed not only to get human response of objective measurement but also to make subjective evaluation of the vibration. The subjective evaluation was estimated using the absolute discomfort threshold of the controlled vibration, which was achieved with the three-down one-up method that is widely used in the field of psychophysics. As the result, apparent mass and apparent eccentric mass as objective human response tend to gradually decrease when frequency of the vibration increases. The absolute discomfort threshold was increased in case of increasing the frequency. Concludingly, the subjective discomfort evaluation is highly correlated with the objective human responses at the range of idle vibration on passenger vehicle.

Acupuncture Treatment in Clinical Studies for Parkinson's Disease : A Literature Review

  • Sohn, Soo Ah;Lee, Kyoung Yun;Kim, Chang Wan;Lee, Yu Jin
    • Journal of Acupuncture Research
    • /
    • v.35 no.4
    • /
    • pp.149-157
    • /
    • 2018
  • Background: Parkinson's disease is the second most common degenerative brain disease after Alzheimer's disease. This study reviewed clinical practice of acupuncture and moxibustion treatment for Parkinson's disease to assess the future direction of these treatments. Methods: The literature search used 5 Korean Internet databases. The search terms were "Parkinson's disease." and "Parkinson (Korean)." 36 papers were selected: 27 case reports, 2 respropective studies, 3 uncontrolled clinical trials, 3 randomized controlled trial, 1 non-randomized controlled trial. Results: Filiform needles were used in most of studies. Pharmacopuncture, electro-acupuncture, and auricular acupuncture therapy were also used in combination with Filiform needles. 2. The most commonly used basic acupoints for Parkinson's disease was Saamchimbeop. The most commonly used form of pharmacopuncture involved Bee-venom. Conclusion: It is expected that treatment of Parkinson's disease with a variety of acupuncture and moxibustion therapies will continue to be studied, in addition to treatments that utilize existing Filiform needle treatments in clinical practice.

Numerical Investigation of the Shock Interaction Effect on the Lateral Jet Controlled Missile

  • Min, Byung-Young;Lee, Jae-Woo;Byun, Yung-Hwan
    • Proceedings of the Korean Society of Propulsion Engineers Conference
    • /
    • 2004.03a
    • /
    • pp.357-364
    • /
    • 2004
  • A computational study on the supersonic flow around the lateral jet controlled missile has been performed. Case studies have been performed by comparing the normal force coefficient and the moment coefficient of a missile body for several different jet flow conditions, angle of attacks, circumferential jet locations, and spouting jet angles. For the several different jet flow conditions, which include the jet pressure, the jet Mach number, and the corresponding jet mass flow rate, the results show that the normal force coefficient is almost proportional to the jet thrust but the moment coefficient is not. Distinctly different flow phenomena can be noticed as the pressure ratio and the jet Mach number increase. By investigating the angle of attack effect to the normal force and the pitching moment, it has been identified that the normal force and the pitching moment show nonlinearity with respect to the angle of attack. From the detailed flow field analyses with respect to the jet flow conditions and the angle of attacks, it is verified that most of the normal force loss and the pitching moment generation are taken place at the low-pressure region behind the jet nozzle. Furthermore, the normal force and the pitching moment characteristics of the missile have been identified by comparing different circumferential jet locations and spouting jet angles.

  • PDF

Development of Optimal Control System for Lighting and HVAC(Heating, Ventilation, Air Conditioning) Using Energy Saving (에너지 절감용 조명 및 공조기기 최적제어 시스템 개발)

  • Jang, Woo-Sung;Song, Yeoung-Seok;Cho, Byung-Lok;Cho, Seok-Hwan
    • The Journal of the Korea institute of electronic communication sciences
    • /
    • v.13 no.5
    • /
    • pp.1029-1036
    • /
    • 2018
  • This paper is a study on the development of optimal control system for lighting and air conditioning equipment to save the energy in campus environment. In the case of controling system developed through this research, lighting and air conditioner are controlled by both information on the number of people entering and leaving the room through the motion sensor and image processing, and the information on temperature and humidity. In addition, energy saving is enabled by the results that are controlled through data integration monitoring and command execution functions according to the control signals.

A Structure-controlled Model for Hot Spring Exploration in Taiwan by Remote Sensing

  • Liu, Jin-King;Yu, Ming-Fang;Ueng, Shiun-Jenq
    • Proceedings of the KSRS Conference
    • /
    • 2003.11a
    • /
    • pp.28-30
    • /
    • 2003
  • Hot Spring Law of Taiwan was passed in legislative assembly on 3 June 2003. Hot springs would become one of the most important natural resources for recreation purposes. Both public and private sectors will invest large amount of capital in this area in the near future. The value of remote sensing technology is to give a critical tool for observing the landscape to find out mega-scaled geological structures, which may not be able to be found by conventional approaches. The occurrences of the hot springs in Taiwan are mostly in metamorphic and sedimentary rocks , other than in volcanic environments. Local geothermal anomaly or heat of springs transfer by liquid convection other than conduction or radiation. The deeply -seated fractures of hard rocks are the conduit of the convection of hot water, which could be as deep as 3000 meters in a hypothetical model of Taiwan. Clues to find outcrops of hot spring can be obtained by a structure-controlled model deduced by geological lineaments observed by satellite images and stereoscopic interpretation of aerial photographs. A case study conducted in Eastern Taiwan will be demonstrated.

  • PDF

Remote Honey Bee Breeding Centre: A Case Study of Heligoland Island in Germany

  • Meyer-Rochow, V.B.;Jung, Chuleui
    • Journal of Apiculture
    • /
    • v.34 no.4
    • /
    • pp.285-293
    • /
    • 2019
  • The honey bee queen shows extreme polyandry and controlling the mating partners can only be possible either by artificial insemination or having remote isolated mating locations. Here we report on the German North Sea island of Heligoland. Because of its location 60 km from the mainland, the lack of a local population of honey bees, its size of just 1.4 ㎢ and suitable weather conditions during the months of May to July, it is considered an ideal location for controlled inseminations of high-quality virgin queen bees with drones deemed genetically superior to others. Methods how to rear virgin queen bees are described and information is provided on the numbers of queen bees, their supporting workers and drone bees that are taken to the island in the mating season. The bee most commonly involved in the Heligoland mating trials has become Apis mellifera carnica strain "Baltica". In one summer, for example, 80 virgin queens (belonging to beekeepers from nine different locations in northern Germany) each with about 600 worker bees plus two drone populations of around 2,000 drones were taken by ship to Heligoland. On their return to the mainland no later than 3.5 weeks after the mating exercise, the beekeepers could register a mating success rate of 80%. This information can help operation management of the new remote mating centre of Weedo Island, Jeonbuk in Korea, which is currently under construction.

Acupuncture for Adult Obstructive Sleep Apnea or Obstructive Sleep Apnea-Hypopnea Syndrome: A Review of the China National Knowledge Infrastructure Database

  • Hye Kyung, Baek;Young Jun, Kim;Yeon Sun, Lee;Hye Ri, Jo;Mi So, Park;Dong Guk, Shin;Hyun A, Shim
    • Journal of Acupuncture Research
    • /
    • v.39 no.4
    • /
    • pp.275-282
    • /
    • 2022
  • The purpose of this study was to analyze acupuncture treatment methods and acupoints used to treat obstructive sleep apnea (OSA) or obstructive sleep apnea-hypoapnea syndrome (OSAHS). The data were retrieved from January 2010 to May 2022 from the China National Knowledge Infrastructure database. The search terms included "adult," "obstructive sleep apnea," "obstructive sleep apnea hypoapnea syndrome," "acupuncture," and "electro-acupuncture." Clinical trials for acupuncture treatment of OSA or OSAHS were included in this review (4 non-randomized controlled studies, 1 was a case report, and 10 randomized controlled studies). For OSA and OSAHS treatment, the acupoints that were most frequently used included REN23, LU7, ST40, EX9, LI11, and DU20. Compared with the control or Western treatment group, the treatment outcome measures of participants in the acupuncture treatment group significantly improved. In some studies, participants in the acupuncture group did not have side effects and the treatment was cost-effective. The data analyzed in this review suggest that acupuncture is an effective treatment for OSA or OSAHS.

Acupuncture Treatment for Gouty Arthritis Using the Search Results of China National Knowledge Infrastructure (CNKI), PubMed: A Literature Review (통풍성 관절염의 침 치료에 대한 최근 연구동향 분석: China National Knowledge Infrastructure (CNKI), PubMed 검색을 중심으로)

  • Hong-Gi Keum;Byung-Cheul Shin
    • Journal of Korean Medicine Rehabilitation
    • /
    • v.33 no.1
    • /
    • pp.31-45
    • /
    • 2023
  • Objectives The aim of this study is to find the future perspective through analyzing the trends of acupuncture treatment for gouty arthritis (GA) by searching the China National Knowledge Infrastructure (CNKI) and PubMed. Methods We searched clinical studies about acupuncture treatment for GA through the searching the electronic database of CNKI and PubMed. We analyzed the characteristics of selected studies according to research design, sample size, publication year, treatment methods, evaluation criteria and adverse events. Results Twenty-nine studies published from January 1, 2015 to July 1, 2022 were selected. They consisted of 25 randomized controlled trials, 3 non-randomized controlled trials, and 1 case reports. In these studies, several types of acupuncture treatments were performed and the most treatment was conventional acupuncture treatment with fine needles. The most commonly used evaluation outcome was effective rate. Conclusions Through this result, the Chinese literature positively reported the effect of acupuncture on GA. However, high-quality evaluation by rigorous research using well-designed and more objective outcomes is required.