• 제목/요약/키워드: Scale Efficiency Change

검색결과 256건 처리시간 0.033초

급성기 족관절 염좌의 근위취혈(近位取穴)과 원위취혈(遠位取穴)의 치료 효과 비교 연구 (The Comparison of Effectiveness between Near Acupuncture Point Needling and Remote Acupuncture Point Needling on Treating Ankle Sprain of Acute Stage)

  • 김대중;최용준;김도호;엄재연;송계화;이진석;조남근
    • Journal of Acupuncture Research
    • /
    • 제24권4호
    • /
    • pp.25-33
    • /
    • 2007
  • Objective : The purpose of this study is to compare the effects of near acupuncture point needling and remote acupuncture point needling on treating ankle sprain of acute stage. Methods : From March 1st, 2007 to May 30th, 2007, the 50 patients who had visited Iksan oriental medical hospital, Wonkwang university with acute ankle sprain were divided into 2 groups ; one group took near acupunture point needling, and the other group took remote acupunture point needling. Both group had been treated with the same additional rest, ice, compression and elevation(RICE) therapy. To evaluating the efficiency of each treatment, Visual Analog Scale(VAS) and Ankle-Hindfoot Scale(AHS) were applied before 1st treatment and after 3rd treatment. Results : As a result of evaluation by using AHS, the score change comparison between the two groups had no significance after the treatment. As a result of evaluation by using VAS, treatment score of remote acupucture point needling was marked lower than score of near acupucture point needling. Conclusion : Remote acupucture point needling is more effective than near acupucture point needling in controlling the pain of acute ankle sprain.

  • PDF

고정식 담체 유무와 반송비에 따른 소규모 하수처리 시스템 내 영양염류 제거 특성 (The Effect of Fixed Media and Recycling Ratio on Nutrients Removal in a Pilot-Scale Wastewater Treatment Unit)

  • 황재훈;조동완;김충환;전병훈
    • 대한환경공학회지
    • /
    • 제35권6호
    • /
    • pp.449-455
    • /
    • 2013
  • 소규모 하수처리시스템에 다양한 반송비와 고정식 담체를 적용하여 합성폐수에서 질소, 인의 제거를 검토하였다. 담체를 첨가 시 질소의 제거율은 40.1%에서 65.1%로 증가하였으나 COD와 인의 제거에는 영향이 없었다(<5%). 반송을 통해 유량을 2배(2Q)로 증가시킨 경우 질소의 제거율은 7% 정도가 증가하였으나, 인 제거율은 반송비가 증가됨에 따라 31.8에서 26.6%로 감소하였다. 무산소조에서 담체에 부착된 미생물은 약 73.4 $mg/cm^2$로 존재하였으며, FISH분석 결과 탈질 미생물인 Pseudomonas aeruginosa 존재 (약 58%)를 확인하였다.

MMORPG를 위한 동적 부하 균등화 기법 (Dynamic Load Balancing Mechanism for MMORPG)

  • 임채균;노경택
    • 한국인터넷방송통신학회논문지
    • /
    • 제9권5호
    • /
    • pp.199-203
    • /
    • 2009
  • 최근 MMORPG의 급격한 성장으로 게임의 동시 접속자수가 계속 증가하는 추세이고, 사용되는 게임 공간의 크기도 대규모로 확대되었다. 기존의 맵 기반 분산 서버 구조는 게임영역을 정해진 사각형 영역으로 분리하고 각 영역에 등록된 참가자들을 그 영역의 담당서버에 할당한다. 따라서 참여자 편중으로 인하여 특정 서버에 부하가 편중되는 문제점을 지니고 있다. 본 논문은 이러한 부하 불균형 문제를 해결하기 위해 서버 간의 경계를 동적으로 변경할 수 있는 기법을 제안하였다. 과부하를 지닌 서버를 결정하여 그 서버와 인접한 서버 중에서 최소의 부하를 지닌 서버를 선택하여 부하를 분담하도록 하였으며, 성능평가를 통하여 제안 기법의 효율성을 보였다.

  • PDF

장거리 구동용 FTS 의 최적 제어에 관한 연구 (A study on the optimal control of Long Stroke Fast Tool Servo Systems)

  • 이상호;이찬홍;김갑순
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2004년도 추계학술대회 논문집
    • /
    • pp.818-821
    • /
    • 2004
  • With a rapid development in the area of micro and ultra precision technology, the micro surface machining of small size parts are explosively increased. Especially, to improve efficiency of various beams in lens and reflector, non-rotational symmetric form and several mm level heights changeable surface can be machined at a time. These geometric complex 3D surface cannot be machined by general short stroke FTS. The long stroke FTS if firmly needed to move directly several mm and have nm level positioning accuracy for the complex surface form. The long stroke FTS used linear motors to drive moving unit long and fine, aero static bearings to decrease friction and moving errors in guide way, optical linear scale with nm level resolution to measure position of FTS. Furthermore, to increase the performance of acceleration of FTS, the light material, such as AL is used for the structure and the high stiffness box type structure is selected. In this paper, the genetic algorithm approach is described to determine a set of design parameters for auto tuning. The authors have attempted to model the design problem with the objective of minimizing the error, such as variable pattern change. This method can give the better alternative than existing other method.

  • PDF

Research and Experimental Implementation of a CV-FOINC Algorithm Using MPPT for PV Power System

  • Arulmurugan, R.;Venkatesan, T.
    • Journal of Electrical Engineering and Technology
    • /
    • 제10권4호
    • /
    • pp.1389-1399
    • /
    • 2015
  • This research suggests maximum power point tracking (MPPT) for the solar photovoltaic (PV) power scheme using a new constant voltage (CV) fractional order incremental conductance (FOINC) algorithm. The PV panel has low transformation efficiency and power output of PV panel depends on the change in weather conditions. Possible extracting power can be raised to a battery load utilizing a MPPT algorithm. Among all the MPPT strategies, the incremental conductance (INC) algorithm is mostly employed due to easy implementation, less fluctuations and faster tracking, which is not only has the merits of INC, fractional order can deliver a dynamic mathematical modelling to define non-linear physiognomies. CV-FOINC variation as dynamic variable is exploited to regulate the PV power toward the peak operating point. For a lesser scale photovoltaic conversion scheme, the suggested technique is validated by simulation with dissimilar operating conditions. Contributions are made in numerous aspects of the entire system, including new control algorithm design, system simulation, converter design, programming into simulation environment and experimental setup. The results confirm that the small tracking period and practicality in tracking of photovoltaic array.

Efficient Plantlet Regeneration via Callus Formation from Leaf Segment of Lilium Oriental Hybrid 'Casa Blanca'

  • Kim Mi-Sun;Jeon Jae-Heung;Youm Jung-Won;Kim Jae-Hyun;Lee Byung-Chan;Kang Won-Jin;Kim Hyun-Soon;Joung Hyouk
    • Journal of Plant Biotechnology
    • /
    • 제7권2호
    • /
    • pp.129-134
    • /
    • 2005
  • Callus induction from a leaf explant has been achieved in Lilium Oriental hybrid 'Casa Blanca'. The highest frequency of callus induction was obtained on MS medium supplemented with 0.5 mg/L BA and 2.0 mg/L NAA after 2 months of culture. The cultures maintained continuously without change in color and type of callus when they cultured in the dark. Plantlet regeneration with a high frequency was achieved from induced calli on the same medium. A number of shoots are formed from one cluster of callus, and bulblets developed into intact plantlets after transfer to hormone-free MS medium. No phenotypic variations were observed among regenerants. Enhancement in plantlet regeneration via callus formation would be expected to facilitate the efficiency of transformation of this Oriental hybrid 'Casa Blanca'.

태양광발전시스템의 장기운전에 의한 성능특성 분석 (The Long-term Operating Evaluation of the Grid Connected Photovoltaic System)

  • 김의환;강승원;김재언
    • 신재생에너지
    • /
    • 제7권2호
    • /
    • pp.28-35
    • /
    • 2011
  • Recently, photovoltaic systems have been devolved into much larger systems up to MW-scale. Photovoltaic industry participants give their focus on power generation capability of photovoltaic modules because their benefits can be decided from the amount of generation. The information on long-term performance change of photovoltaic modules helps to estimate the amount of power generation and evaluate the economic cost-benefits. Long-term performance of a PV system has been analyzed with operation data for 12 years from 1999 to 2010. In the first year, the amount of yearly power generation was 57.7 MWh with 13.2% capacity factor. In 2007, the amount of yearly generation was 44.3 MWh with 10.14% capacity factor, and in 2010, the amount was decreased down to 38.1 MWh with 8.7% capacity factor. The result means that long-term capacity factor has been 4.5% decreased for 12 years and that the amount of generation has been decreased 34.0% for 12 years which is 2.8 % per year. The latter capacity factor has been decreased faster than 0.20%, the average rate for 10 years. The performance decrease of the PV system is meant to be accelerated. The decrease of performance and utilization is due to aged deterioration of photovoltaic modules and lowering conversion efficiency of PCS.

우리나라와 노르웨이의 선망어업 현황 및 생산구조 비교 (Comparison of Production Structure of Purse Seine Fishery in Korea and Norway)

  • 김대영
    • 수산해양교육연구
    • /
    • 제27권1호
    • /
    • pp.308-318
    • /
    • 2015
  • In order to improve the competitiveness of Korean large purse seine fishery, the purpose of this study is to find out the problems and present the improvement of the production structure of Korean large purse seine fishery by comparing to the production structure of Norwegian purse seine fishery. Norwegian purse seine fishery has been operating labor and energy-saving systems through a single wire operation and avoiding fishing competition through the introduction of IVQ system with different types of fishing vessel and obtaining benefits from Leading fishery management integrated with fish pumps and cooling water systems. In contrast, our country has a large purse seine fishery issues such as high cost and low efficiency of production structures, the volatility of mackerel resources, the lack of leading fishery management after catching fishes, the reduction of fishing ground in accordance with the North East Asia EEZ system. To solve these problems, initiatives to improve the structure of our large purse seine fishery are as follows: First, Implementing the promotion of the effective immature fishes management and establishing Korea-China-Japan resource management system. Second, the promotion of reduction of fleet size, the review of possible single fishing operation, leading out to strengthen its competitiveness by switching to energy-efficient production systems through enhanced efforts at fisheries catches steps. Third, it is necessary to realize corporate through the diversification of business areas and the large-scale commercialization of production structure.

새 도선 감는 방법을 적용한 전기장 이용 스케일 제거 (Prevention of Particulate Scale with a New winding Method in the Electronic Descaling Technology)

  • 손창현;구상모;김창수;김건우
    • 대한기계학회논문집B
    • /
    • 제26권5호
    • /
    • pp.658-665
    • /
    • 2002
  • This paper presents a new winding method in electronic descaling (ED) technology. Conventional ED technology Produces an oscillating electric field via Faraday's law to provide the necessary molecular agitation to dissolve mineral ions. However, the proposed method produces an additional agitation force for mineral ions, called Lorentz's force. Experiments were performed using various Renolds numbers. A series of tests was conducted to measure the pressure drop across the test section and the overall heat transfer coefficient as a function of time. In order to accelerate the rate of fouling, artificial hard water, 1000ppm CaCO$_3$, was used throughout the tests. The results show that the new winding method accelerates the collision of the mineral ions, thereby improving the system efficiency. The present study can develope more effective fouling-removing equipment with change of estabishment method of coil.

냉장고용 소형 축류홴의 통계학적 3차원 난류유동 특성에 관한 연구 (A Study on the Three Dimensional Statistical Turbulent Flow Characteristics Around a Small-Sized Axial Fan for Refrigerator)

  • 김장권
    • 대한기계학회논문집B
    • /
    • 제25권6호
    • /
    • pp.819-828
    • /
    • 2001
  • The operating point of a small-sized axial fan is strongly dependent upon the system resistance. Therefore, the turbulent flow characteristics around a small-sized axial fan may change significantly according to the operating point. This study represents three-dimensional turbulent flow characteristics around a small-sized axial fan measured at the ideal design point $\phi$=0.25, which is equivalent to the maximum total efficiency point, by using three dimensional fiber-optic type LDA system. This LDA system is composed of a 5 W Argon-ion laser, two optics in back-scatter mode, three BSAs, a PC, and a three-dimensional automatic traversing system. A kind of paraffin fluid is used to supply particles by means of fog generator. Mean velocity profiles downstream of a small-sized axial fan along the radial distance show that the streamwise and the tangential components exist in a predominant manner, while the radial component has a small scale distribution and shows the inflection which its flow direction is inward or outward. Moreover, the turbulent intensity profiles show that the radial component exists the most greatly among turbulent energies.