• Title/Summary/Keyword: contribution amount

검색결과 395건 처리시간 0.029초

유산균 Probiotics와 생명의 연장에 대한 고찰 (Probiotics and Prolongation of Life)

  • 오세종
    • Journal of Dairy Science and Biotechnology
    • /
    • 제26권2호
    • /
    • pp.31-37
    • /
    • 2008
  • One hundred one years have passed since Metchnikoff made his first scientific contribution to probiotics study. Intestinal lactic acid bacteria (LAB) for humans are closely associated with the host's health because LAB is an important biodefense factor in preventing colonization and subsequent proliferation of pathogenic bacteria in the intestine. A probiotic is recently defined as "live microorganisms that when administered in adequate amount confer a health benefit on the host". Some species of LAB have been claimed as probiotics, such as Lactobacillus acidophilus, L. casei, L. fermentum, L. plantarum, L. reuteri, and Lactococcus lactis. For understanding the general mechanism of probiotics, this paper would explore the early studies relating to probiotics and intestinal microbiota, and briefly introduce the Prolongation of Life written by Elie Metctmikoff.

  • PDF

1994년 수도권 지역에서의 시정과 미세 입자상물질 화학조성과의 관계해석 (Chemical Composition of Fine Aerosol Associated with Visibility Degradation in Seoul Metropolitan Area in 1994)

  • 한진석;김병곤;김신도
    • 한국대기환경학회지
    • /
    • 제12권4호
    • /
    • pp.377-387
    • /
    • 1996
  • This study was carried out to monitor the visibility including measurement and analysis of the various parameters such as particle size distribution, chemical composition, and meteorotical conditions to understand the characteristics and causes of this phenomenon. According to the analysis of intensive sampling, $SO_4^{2-}, NO-3^-, Cl^-, NH_4^+$ ion concentration increased together with the mass concentration around 1 $\mu$m in the case of low visibility. $(NH_4)_2SO_4, NH_4NO_3$, and $NH_4Cl$ were thought to be the major components of fine particles. The statistical analysis showed that the scattering effect of particle was 81.2%, the absorption effect was 14.9%. Therefore, these effects were the major factors to reduce the visibility. In conclusion, the visibility was reduced by the fine particle of sulfate (18.6%), nitrate (14.2%), organic carbon (10.8%), element carbon (25.8%), and residual (24.8%) during this study.

  • PDF

Electromagnetic Properties of Bi System Superconductor for Neutron Irradiation

  • Lee, Sang-Heon;Choi, Yong
    • 한국분말야금학회:학술대회논문집
    • /
    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
    • /
    • pp.1239-1240
    • /
    • 2006
  • Effects of $Ag_2O$ doping on the electromagnetic properties in the BiSrCaCuO superconductors. The electromagnetic properties of $Ag_2O$ doped and undoped BiSrCaCuO superconductor were evaluated to investigate the contribution of the pinning centers to the magnetic effect. It was confirmed experimentally that a large amount of magnetic flux was trapped in the $Ag_2O$ doped sample than that in the undoped one, indicating that the pinning centers of magnetic flux are related closely to the occurrence of the magnetic effect. It is considered that the area where normal conduction takes place increases by adding $Ag_2O$ and the magnetic flux penetrating through the sample increases. The results suggested that Ag acts to increase pinning centers of magnetic flux, contributing to the occurrence of the electromagnetic properties.

  • PDF

Protein Aggregation and Adsorption upon In vitro Refolding of Recombinant Pseudomonas Lipase

  • Lee, Young-Phil;Rhee, Joon-Shick
    • Journal of Microbiology and Biotechnology
    • /
    • 제6권6호
    • /
    • pp.456-460
    • /
    • 1996
  • Recombinant Pseudomonas lipase was used to study protein aggregation and adsorption upon in vitro refolding. Protein adsorption as well as aggregation was responsible for major side reactions upon in vitro refolding as a function of protein concentration. The optimal range of protein concentration was determined by the relative contribution of protein aggregation and adsorption. Above the optimal range, the yield of active lipase inversely correlated with protein aggregation, showing a competition between folding and aggregation. However, adsorption of protein rather than protein aggregation is thought to contribute as a major side reaction of the refolding process at sub-optimal concentrations at which the formation of aggregates should be more reduced. Protein aggregation was influenced by the amount of guanidine hydrochloride in the refolding solvent. The refolding temperature was a critical factor determining the extent of protein aggregation. The refolding yield was also affected by the dilution fold and dilution mode, which suggests that the refolding process might kinetically compete with the rate of mixing.

  • PDF

물류 차량을 위한 효율적인 데이터 전송 방법 (An Efficient Data Transmission Scheme for Logistics Vehicles)

  • 김종효;양정민
    • 대한임베디드공학회논문지
    • /
    • 제13권2호
    • /
    • pp.93-100
    • /
    • 2018
  • In this paper, we present a novel scheme of data transmission for logistics vehicles connected with 3G mobile communication networks. The proposed method enhances the efficiency of data transmission by varying the packet transmission period according to the vehicle speed and by reducing the amount of transmitted data using a reduced packet structure. The main contribution is to present the experimental verification in which the proposed method is applied to commercial logistics vehicles that operate with networked data transmission modules. Being compared with the existing method, the proposed scheme shows superior performance in terms of data reduction and transmission speed.

퍼미언스 방법을 이용한 스위치드 릴럭턴스 전동기의 인덕턴스 산정 (Inductance Calculation in a Switched Reluctance Motor using Permeance Method)

  • 이치우
    • 전기학회논문지
    • /
    • 제61권12호
    • /
    • pp.1836-1842
    • /
    • 2012
  • Torque is proportional to the rate of change of inductance in a switched reluctance motor (SRM), and hence, phase inductance is an important parameter in determining the behavior of an SRM. Therefore, the accurate prediction of inductance with respect to rotor position makes a significant contribution to designing an SRM and its analytical approach is not straightforward due to nonlinear flux distribution. Although several different approaches using a finite element analysis (FEA) or curve-fitting tool have been employed to compute phase inductance [2-5], they are not suitable for a simple design procedure because the FEA necessitates a large amount of time in both modeling and solving with complexity for every motor design, and the curve-fitting requires the data of flux linkage from either an experimental test or an FEA simulation. In this paper, phase inductance is predicted by means of a permeance method, and the proposed approach is analytically verified in terms of the accuracy of estimated inductance compared to inductance obtained by FEA.

예약요금제에서 사회적 이익을 고려한 예비력 요금에 관한 연구 (A Study on the Social Benefit Maximizing Reserve Pricing)

  • 김성수;정해성;박종근;최준영;홍준희
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1995년도 하계학술대회 논문집 B
    • /
    • pp.581-583
    • /
    • 1995
  • This paper presents a theory on the pricing and allocation of spinning reserve. It is shown in this paper, that it is possible to maintain system security with many participants each attempting to optimize their own benefit, through pricing incentive. Participant offers power consumption/generation and reserve contribution according to its price. And Price setter only distribute pricing signal to acquire system security. Participants induce disturbance on power system and they pay the penalty according to the size of disturbance. And they also offers some reserve capacity to earn reserve cost. In this scheme, the amount of data communication is very small.

  • PDF

풍화화강토 사면에서 강우로 인한 모관흡수력 변화에 대한 실험 연구 (In-situ Monitoring of Matric Suctions in a Weathered Granite Soil Slope)

  • 이인모;조우성;김영욱;성상규
    • 한국지반공학회:학술대회논문집
    • /
    • 한국지반공학회 2002년도 봄 학술발표회 논문집
    • /
    • pp.509-516
    • /
    • 2002
  • Rainfall-induced landslides in a weathered granite soil slope have mostly relative shallow slip surfaces above the groundwater table The pore-water pressure of soil above the groundwater table is usually negative. This negative pore-water pressure(or matric suction) has been found to make a large contribution to the slope stability. Therefore, the variation of in-situ matric suction profiles with time in a soil slope should be understood. In this study, a field measurement program was carried out from June to August, 2001 to monitor in-situ matric suctions and volumetric water contents in a weathered granite soil slope. The influence of climatic conditions on the variation of in-situ matric suctions could be found to decrease rapidly with depth. It could be found that decrement of matric suction induced by precipitation is affected not only by the amount and duration of rainfalls but also by the initial matric suction just prior to rainstorms. The soil-water characteristic from the field monitoring tends toward the wetting path of SWCC obtained from the laboratory test.

  • PDF

Electromagnetic Properties of Bi System Superconductor for Magnetic Levitation Car Maglev

  • Lee, Sang-Heon
    • Journal of Electrical Engineering and Technology
    • /
    • 제2권1호
    • /
    • pp.102-105
    • /
    • 2007
  • Effects of $Ag_2O$ doping on the electromagnetic properties in the BiSrCaCuO superconductors. The electromagnetic properties of the $Ag_2O$ doped and undoped BiSrCaCuO superconductor were evaluated to investigate the contribution of the pinning centers to the magnetic effect. It was confirmed experimentally that a large amount of magnetic flux was trapped in the $Ag_2O$ doped sample than that in the undoped one, indicating that the pinning centers of magnetic flux are related closely to the occurrence of the magnetic effect. It is considered that the area where normal conduction takes place increases by adding $Ag_2O$ and the magnetic flux penetrating through the sample increases. The results suggested that Ag acts to increase the pinning centers of the magnetic flux, contributing to the occurrence of the electromagnetic properties.

스위치드 릴럭턴스 전동기의 회전자 정렬과 비정렬 위치에서의 인덕턴스 예측 (Analytical Estimation of Inductance at Aligned and Unaligned Rotor Positions in a Switched Reluctance Motor)

  • 이치우
    • 전기학회논문지
    • /
    • 제61권1호
    • /
    • pp.34-40
    • /
    • 2012
  • Flux linkage of phase windings or phase inductance is an important parameter in determining the behavior of a switched reluctance motor (SRM) [1-8]. Therefore, the accurate prediction of inductance at aligned and unaligned rotor positions makes a significant contribution to the design of an SRM and its analytical approach is not straightforward due to nonlinear flux distribution. Although several different approaches using a finite element analysis (FEA) or curve-fitting tool have been employed to compute phase inductance [2-5], they are not suitable for a simple design procedure because the FEA necessitates a large amount of time in both modeling and solving with complexity for every motor design, and the curve-fitting requires the data of flux linkage from either an experimental test or an FEA simulation. In this paper, phase inductance at aligned and unaligned rotor positions is estimated by means of numerical method and magnetic equivalent circuit as well, and the proposed approach is analytically verified in terms of the accuracy of estimated inductance compared to inductance computed by an FEA simulation.