• 제목/요약/키워드: simultaneous

검색결과 6,424건 처리시간 0.035초

Simultaneous precision positioning and vibration suppression of reciprocating flexible manipulators

  • Ma, Kougen;Ghasemi-Nejhad, Mehrdad N.
    • Smart Structures and Systems
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    • 제1권1호
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    • pp.13-27
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    • 2005
  • Simultaneous precision positioning and vibration suppression of a reciprocating flexible manipulator is investigated in this paper. The flexible manipulator is driven by a multifunctional active strut with fuzzy logic controllers. The multifunctional active strut is a combination of a motor assembly and a piezoelectric stack actuator to simultaneously provide precision positioning and wide frequency bandwidth vibration suppression capabilities. First, the multifunctional active strut and the flexible manipulator are introduced, and their dynamic models are derived. A control strategy is then proposed, which includes a position controller and a vibration controller to achieve simultaneous precision positioning and vibration suppression of the flexible manipulator. Next, fuzzy logic control approach is presented to design a fuzzy logic position controller and a fuzzy logic vibration controller. Finally, experiments are conducted for the fuzzy logic controllers and the experimental results are compared with those from a PID control scheme consisting of a PID position controller and a PID vibration control. The comparison indicates that the fuzzy logic controller can easily handle the non-linearity in the strut and provide higher position accuracy and better vibration reduction with less control power consumption.

EMTP 시뮬레이션을 통한 배전선로의 1선 지락 사고시 화재 조사 기법에 관한 연구 (A Study on Fire Investigation Technique For Single Line to Ground Faults in Distribution Line Using EMTP Simulation)

  • 유정현;김희식;이훈기;조용선
    • 한국안전학회지
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    • 제33권3호
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    • pp.21-26
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    • 2018
  • Approximately 20% of the total fire is electrical fire, and electrical energy is a potential source of heat. Large-scale fault currents that occur during a line ground fault flow into electric utility poles, electric power equipment, or electric appliances of the customer, and cause simultaneous electrical fire. In this paper, we investigated the possibility of fire through the change of fault current flowing in faulty and sound feeder in case of 1 line ground fault in 22.9 kV distribution line. We propose a fire investigation analysis method for simultaneous multiple electrical fire such as evidence analysis method, and fault current occurrence confirmation method in case of fire accident by analyzing the fault current occurring in the ground fault in the distribution line using EMTP, electric power system analysis program.

Simultaneous Detection and Identification of Bacillus cereus Group Bacteria Using Multiplex PCR

  • Park, Si-Hong;Kim, Hyun-Joong;Kim, Jae-Hwan;Kim, Tae-Woon;Kim, Hae-Yeong
    • Journal of Microbiology and Biotechnology
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    • 제17권7호
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    • pp.1177-1182
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    • 2007
  • Bacillus cereus group bacteria share a significant degree of genetic similarity. Thus, to differentiate and identify the Bacillus cereus group efficiently, a multiplex PCR method using the gyrB and groEL genes as diagnostic markers is suggested for simultaneous detection. The assay yielded a 400 bp amplicon for the groEL gene from all the B. cereus group bacteria, and a 253 bp amplicon from B. anthracis, 475 bp amplicon from B. cereus, 299 bp amplicon from B. thuringiensis, and 604 bp amplicon from B. mycoides for the gyrB gene. No nonspecific amplicons were observed with the DNA from 29 other pathogenic bacteria. The specificity and sensitivity of the B. cereus group identification using this multiplex PCR assay were evaluated with different kinds of food samples. In conclusion, the proposed multiplex PCR is a reliable, simple, rapid, and efficient method for the simultaneous identification of B. cereus group bacteria from food samples in a single tube.

Impact of Lactic Acid and Hydrogen Ion on the Simultaneous Fermentation of Glucose and Xylose by the Carbon Catabolite Derepressed Lactobacillus brevis ATCC 14869

  • Jeong, Kyung Hun;Israr, Beenish;Shoemaker, Sharon P.;Mills, David A.;Kim, Jaehan
    • Journal of Microbiology and Biotechnology
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    • 제26권7호
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    • pp.1182-1189
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    • 2016
  • Lactobacillus brevis ATCC 14869 exhibited a carbon catabolite derepressed phenotype that has ability to consume fermentable sugars simultaneously with glucose. To evaluate this unusual phenotype under harsh conditions during fermentation, the effects of lactic acid and hydrogen ion concentrations on L. brevis ATCC 14869 were examined. Kinetic equations describing the relationship between specific cell growth rate and lactic acid or hydrogen ion concentration were deduced empirically. The change of substrate utilization and product formation according to lactic acid and hydrogen ion concentration in the media were quantitatively described. Although the simultaneous utilization has been observed regardless of hydrogen ion or lactic acid concentration, the preference of substrates and the formation of two-carbon products were changed significantly. In particular, acetic acid present in the medium as sodium acetate was consumed by L. brevis ATCC 14869 under extreme pH of both acid and alkaline conditions.

속도와 2차 저항의 동시 추정이 가능한 유도전동기의 극 저속 영역 센서리스 속도제어 (Sensorless Control of Induction Motors with Simultaneous Estimation of Speed and Rotor Resistance in the Very Low Speed Region)

  • 정석권;이진국;유삼상
    • 대한전기학회논문지:전기기기및에너지변환시스템부문B
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    • 제53권9호
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    • pp.552-561
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    • 2004
  • This paper is concerned with a new speed sensorless induction motor scheme which can be successfully applied to at any speed including even zero speed. The proposed method is robust against rotor resistance variations. In addition, simultaneous on-line estimations of speed and rotor resistance are realized based on a feedforward type torque control approach. The rotor flux with a low frequency sinusoidal waveform has been utilized to help the simultaneous estimation for both speed and rotor resistance. The control scheme has no current minor loop to determine voltage references. Since the proposed estimation does not depend on any derivative terms of currents and stator voltages, it offers a good performance at extremely low speed region for sensorless induction motor. Furthermore, the proposed control is simply using motor parameters and stator currents without determining any PI gains for current feedback and any signal injection for the rotor resistance estimation. Finally, both simulation and experimental results are given to show the effectiveness of this method.

Inclusive Growth and Innovation: A Dynamic Simultaneous Equations Model on a Panel of Countries

  • Bresson, Georges;Etienne, Jean-Michel;Mohnen, Pierre
    • STI Policy Review
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    • 제6권1호
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    • pp.1-23
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    • 2015
  • Based on the work of Anand et al. (2013) we measure inclusive income growth, which combines growth in gross domestic product (GDP) per capita and growth in the equity of the income distribution. Extending the work of Causa et al. (2014), we estimate a dynamic simultaneous structural equations model of GDP per capita and inclusive income on panel data for 63 countries over the 1990-2013 period. We estimate both equations in error correction form by difference GMM (generalized method of moments). Among the explanatory variables of the level and the distribution of GDP per capita we include R&D (research and development) expenditure per capita. In OECD countries we obtain a large positive effect of R&D on GDP. R&D is found to have a positive effect on the social mobility index but its impact on the income equity index at first decreases, then switches around to become slightly positive in the long run. In non- OECD countries, R&D is found to decrease inclusive income, mostly through a negative growth effect but also because of a slightly increasing income inequity effect.

동시냉난방 열펌프 시스템의 운전모드별 성능특성에 관한 실험적 연구 (Experimental Study on the Performance Characteristics of a Simultaneous Heating and Cooling Heat Pump System at Each Operating Mode)

  • 강훈;이선일;주영주;정현준;김용찬;최종민
    • 설비공학논문집
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    • 제19권10호
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    • pp.679-686
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    • 2007
  • The cooling load in winter season is significant in many commercial buildings and hotels because of the usage of office equipments and the high efficiency of wall insulation. The development of a multi-heat pump that can cover heating and cooling simultaneously for each indoor unit is required. In this study, a 4-room simultaneous heating and cooling heat pump system was designed and its performance was measured at each operating mode. The system used R-410A and adopted variable speed compressor. The problems on the designed system were analyzed and defined. In addition, the solutions of the problems were suggested to improve system efficiency and to obtain the stable operation.

들로네(S. Delauunay)의 예술이 표현된 의상ㆍ직물 디자인에 관한 연구 (A Study on Fashion and Textile Design expressed in S. Delauunay′s Art)

  • 정혜정
    • 한국의상디자인학회지
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    • 제5권2호
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    • pp.103-113
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    • 2003
  • This paper analyses the geometric aspect of Sonia Delaunay′s works on the basis of design elements and principles. Geometric pattern is one of the distinct features of early 20th century avant-garde works. The significance of its pattern and colour comes from the fact that it has not only influenced the contemporary fine art but also offered the basic principle of modern costume design. In 1925 she was designing clothes which could be worn today without appearing old-fashioned. She foresaw the future trends in fashion and interior decoration. One might claim she belongs to the avant-garde even today and no less astonishing a phenomenon than she was in 1925. Sonia Delaunay′s art was one of the first expressions of abstract painting and her "simultaneous contrasts" are among the earliest example of the aesthetic. In Delaunay′s geometric abstraction it is found that the technique of "simultaneous contrasts" is exploited almost without exception. Colour as well as Collage was the favourite technique Delnaunay used in creating a distinct simultaneity. Many "inobjective" paintings as she herself called unite the rigour of simple geometric forms with an inner life and poetry which emanate from the richness of the colour, the musicality of the rhythm, the vibrant breadth of the execution.

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적합도 공유 기법을 적용한 향상된 FastSLAM 알고리즘 (An Improved FastSLAM Algorithm using Fitness Sharing Technique)

  • 권오성;현병용;서기성
    • 한국지능시스템학회논문지
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    • 제22권4호
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    • pp.487-493
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    • 2012
  • SLAM(Simultaneous Localization And Mapping)은 주변 환경에 대한 지도 작성과 자신의 위치를 인식하는 기법으로 주행 로봇 분야에서 널리 사용되고 있다. FastSLAM(A Factored Solution to the SLAM)은 파티클 필터와 확장형 칼만 필터를 기반으로 한 대표적인 SLAM 기법중의 하나이나, 재추출 단계에서 입자들의 다양성이 상실되는 문제가 제기되고 있다. 본 논문에서는 적합도 공유기법을 사용하여 입자들의 다양성 상실에 관한 문제를 보완하는 방법을 제시하고, 기존의 기법들과 성능을 비교 및 분석한다.

Development of Pilot-Scale Scrubber for Simultaneous Removal of $SO_2/NO$

  • Jung, Seung-Ho;Jeong, Gwi-Taek;Lee, Gwang-Yeon;Park, Don-Hee;Cha, Jin-Myeong
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2005년도 생물공학의 동향(XVII)
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    • pp.468-474
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    • 2005
  • SOx and NOx are known major precursors of acid rain and thus the abatement of their emissions is a major target in air pollution control. To obtain basic data on the removal process of simultaneous $SO_2/NO$, the optimal reaction condition and the composition of reaction solution for simultaneous removal of $SO_2/NO$, ware investigated using a bubble column reactor. Pilot scrubber was consisted of scrubber, filter and control box. Dust removal rate was 83, 92, and 97% with catalyst flux of 0.5, 0.8, 1.5 L/min, respectively Average dust removal efficiency with a kind of nozzle was about 94 and 90% in STS FF6.5 (5/8in.) and 14 of P.P W(1.0in.), respectively Dust and $SO_2$ were removed more than 98-96% regardless of reactor number. In the case of NO gas, removal yield of 83.3% was achieved after 48 hours in 1 stage, also removal yield of 95.7% was reached in 2 stages. In tile case of application of STS (5/8 in.) and P.P (1.0 in.) as used fill packing, removal efficiency was reached higher than 98% without related to of kind of fill packing.

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