• 제목/요약/키워드: Transport loss

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Glucose Transport through N-Acetylgalactosamine Phosphotransferase System in Escherichia coli C Strain

  • Kim, Hyun Ju;Jeong, Haeyoung;Lee, Sang Jun
    • Journal of Microbiology and Biotechnology
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    • 제32권8호
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    • pp.1047-1053
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    • 2022
  • When ptsG, a glucose-specific phosphotransferase system (PTS) component, is deleted in Escherichia coli, growth can be severely poor because of the lack of efficient glucose transport. We discovered a new PTS transport system that could transport glucose through the growth-coupled experimental evolution of ptsG-deficient E. coli C strain under anaerobic conditions. Genome sequencing revealed mutations in agaR, which encodes a repressor of N-acetylgalactosamine (Aga) PTS expression in evolved progeny strains. RT-qPCR analysis showed that the expression of Aga PTS gene increased because of the loss-of-function of agaR. We confirmed the efficient Aga PTS-mediated glucose uptake by genetic complementation and anaerobic fermentation. We discussed the discovery of new glucose transporter in terms of different genetic backgrounds of E. coli strains, and the relationship between the pattern of mixed-acids fermentation and glucose transport rate.

수산물 저온수송의 최적방법에 관한 연구 I. 고등어의 빙장수송 (Studies on the Optimum Method of Cold Transport of Marine Products I. Transport of Iced Mackerel)

  • 허종화;함낙계;이종갑;최선홍;김진국
    • 대한설비공학회지:설비저널
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    • 제9권2호
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    • pp.111-117
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    • 1980
  • The optimum methods of transport of fresh mackerel caught at korean coast and neighboring sea were investigated. The quality of mackerel after 3 day-stored with ice showed that the freshness were still kept. The temperature fluctuation of mackerel during transport with ice from Busan to Seoul indicated below $5^{\circ}C$, recommended by I.I.R. Heat loss of iced mackerel in transit was calculated and converted into ice weight in case of cargo truck and insulated truck. It was assumed that the semi-dressed mackerels were more effective and economic than the round ones during transport.

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패킷망에서 MPEG-4 비디오 오류처리 최적화 방식 연구 (Packet loss resilience methods of MPEG-4 Video)

  • 이상조;서덕영
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 2000년도 정기총회 및 학술대회
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    • pp.15-19
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    • 2000
  • This paper is about MPEG-4 error resilience tools of video streaming on packet service(ex, Internet). It is need to packetization for MPEG-4 video transport by packet unit on MPEG-4 system, this paper suggest packetization method of minimizing packet error on packet service[1]. FEC(Forward Error Correction) and retransmission is usually used for recovery of packet loss, and this paper suggest applying these method to DMIF(Delivery Multimedia Integration Framework) for minimizing packet loss[2].

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다층 고온 초전도케이블에서의 전류분류 및 손실 계산 (Current Distribution and Loss Calculation of a Multi-layer HTS Transmission Cable)

  • 이승욱;차귀수;이지광;한송엽
    • 한국초전도저온공학회:학술대회논문집
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    • 한국초전도저온공학회 2000년도 KIASC Conference 2000 / 2000년도 학술대회 논문집
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    • pp.29-32
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    • 2000
  • Superconducting transmission cable is one of interesting part in power application using high temperature super-conducting wire as transformance. One important parameter in HTS cable design is transport current distribution because it is related with current transmission capacity and loss. In this paper, we present the calculation theory of current distribution for multi-layer cable using the electric circuit model and in example, calculation results of current distribution and AC loss in each layer of 4-layer HTS transmission cable.

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경로설정 최적화와 바인딩 확장을 이용한 개선된 Mobile IP 핸드오프 기법 (An Enhanced Mobile IP Handoff Mechanism using Routing Optimization and Binding Extension)

  • 오현우
    • 한국시뮬레이션학회:학술대회논문집
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    • 한국시뮬레이션학회 1999년도 추계학술대회 논문집
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    • pp.127-132
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    • 1999
  • A mobile IP is proposed to support host mobility over the current Internet. One of the most important issues on the host mobility is location and routing schemes that allow mobile hosts to move effectively from one site to another. In a Mobile IP environment, frequent handoffs are likely to degrade the performance by minimizing the loss of datagrams during handoffs. The handoff scheme is using routing optimization and binding extension to improve the performance by minimizing the average transfer delay of messages and packet loss. Simulation details show the improvement of transport delays and packet loss rate.

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A Comparative Study on Marine Transport Contract and Marine Insurance Contract with Reference to Unseaworthiness

  • Pak, Jee-Moon
    • Journal of Korea Trade
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    • 제25권2호
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    • pp.152-177
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    • 2021
  • Purpose - This study analyses the excepted requirement and burden of proof of the carrier due to unseaworthiness through comparison between the marine transport contract and marine insurance contract. Design/methodology - This study uses the legal analytical normative approach. The juridical approach involves reviewing and examining theories, concepts, legal doctrines and legislation that are related to the problems. In this study a literature analysis using academic literature and internet data is conducted. Findings - The burden of proof in case of seaworthiness should be based on presumed fault, not proved fault. The burden of proving unseaworthiness/seaworthiness should shift to the carrier, and should be exercised before seeking the protections of the law or carriage contract. In other words, the insurer cannot escape coverage for unfitness of a vessel which arises while the vessel is at sea, which the assured could not have prevented in the exercise of due diligence. The insurer bears the burden of proving unseaworthiness. The warranty of seaworthiness is implied in hull, but not protection and indemnity policies. The 2015 Act repeals ss. 33(3) and 34 of MIA 1906. Otherwise the provisions of the MIA 1906 remain in force, including the definition of a promissory warranty and the recognition of implied warranties. There is less clarity about the position when the source of the loss occurs before the breach of warranty but the actual loss is suffered after the breach. Nonetheless, by s.10(2) of the 2015 Act the insurer appears not to be liable for any loss occurring after the breach of warranty and before there has been a remedy. Originality/value - When unseaworthiness is identified after the sailing of the vessel, mere acceptance of the ship does not mean the party waives any claims for damages or the right to terminate the contract, provided that failure to comply with the contractual obligations is of critical importance. The burden of proof with regards to loss of damage to a cargo caused by unseaworthiness is regulated by the applicable law. For instance, under the common law, if the cargo claimant alleges that the loss or damage has been caused by unseaworthiness, then he has the burden of proof to establish the followings: (i) that the vessel was unseaworthy at the beginning of the voyage; and that, (ii) that the loss or damage has been caused by such unseaworthiness. In other words, if the warranty of seaworthiness at the inception of the voyage is breached, the breach voids the policy if the ship owner had prior knowledge of the unseaworthy condition. By contrast, knowingly permitting the vessel to break ground in an unseaworthy condition denies liability only for loss or damage proximately caused by the unseaworthiness. Such a breach does not, therefore, void the entire policy, but only serves to exonerate the insurer for loss or damage proximately caused by the unseaworthy condition.

고속 전송을 위한 적응형 FEC 및 전송률 제어 (Adaptive FEC and Rate Adaptation for High-speed Transport)

  • 장혜영;김종원
    • 한국통신학회논문지
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    • 제30권3B호
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    • pp.85-94
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    • 2005
  • 본 논문은 적응형 오류제어 기법을 바탕으로 신뢰성 있는 UDP 기반의 미디어 고속 전송을 제안한다. 제안된 적응형 전송기법은 대역폭의 변화에 효과적으로 대처하기 위해서 네트워크 모니터링을 기반으로 잉여 데이터의 양을 제어한다. 수신측 피드백은 패킷 손실의 유형, 전송률 등의 수신 상황을 송신측이 인지하도록 하여 앞으로 발생될 네트워크 상황을 예측하고 이를 바탕으로 전송률과 적응형 FEC 코드 조합을 적응적으로 제어함으로써 신뢰성 있는 전송을 가능하게 한다. 제안된 시스템의 성능을 측정하기 위한 고속 네트워크에서의 전송 실험은 수백 Mbps의 전송 속도를 보이며 향상된 신뢰성을 보여준다.

전류분포가 3본-도체의 교류손실 특성에 미치는 영향 (Influence of Current Distributions on AC Loss Characteristics in a 3-conductor)

  • 정재훈;류경우
    • 한국초전도저온공학회:학술대회논문집
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    • 한국초전도저온공학회 2003년도 학술대회 논문집
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    • pp.206-209
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    • 2003
  • AC loss is an important issue in the design of high-T$_{c}$ superconducting power cables which consist of a number of Bi-2223 tapes wound on a former. In the cables, the tapes have different critical currents intrinsically. And they are electrically connected to each other and current leads. These make loss measurements considerably complex, especially for short samples of laboratory size. So special cautions are required in the positioning of voltage leads for measuring the true loss voltage. In this work we have prepared a conductor composed of three Bi-2223 tapes with different critical currents. The ac loss characteristics in the conductor have experimentally investigated. The loss tests indicate that the ac loss is dependent on arrangements of voltage leads but not on their contact positions. The measured losses in the conductor also agree well with the sum of the transport losses measured in each Bi-2223 tape.e.

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전류분포가 3본-도체의 교류손실 특성에 미치는 영향 (Influence of Current Distributions on AC Loss Characteristics in a 3-conductor)

  • 정재훈;류경우
    • 한국초전도저온공학회:학술대회논문집
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    • 한국초전도저온공학회 2003년도 학술대회 논문집
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    • pp.7-10
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    • 2003
  • AC loss is an important issue in the design of high-T$_{c}$ superconducting power cables which consist of a number of Bi-2223 tapes wound on a former. In the cables, the tapes have different critical currents intrinsically. And they are electrically connected to each other and current leads. These make loss measurements considerably complex, especially for short samples of laboratory size. So special cautions are required in the positioning of voltage leads for measuring the true loss voltage. In this work we have prepared a conductor composed of three Bi-2223 tapes with different critical currents. The ac loss characteristics in the conductor have experimentally investigated. The loss tests indicate that the ac loss is dependent on arrangements of voltage leads but not on their contact positions. The measured losses in the conductor also agree well with the sum of the transport losses measured in each Bi-2223 tape.e.

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Effects of Water-misting Sprays with Forced Ventilation after Transport during Summer on Meat Quality, Stress Parameters, Glycolytic Potential and Microstructures of Muscle in Broilers

  • Jiang, N.N.;Xing, T.;Wang, P.;Xie, C.;Xu, X.L.
    • Asian-Australasian Journal of Animal Sciences
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    • 제28권12호
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    • pp.1767-1773
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    • 2015
  • Effects of water-misting sprays with forced ventilation after transport during summer on meat quality, stress parameters, glycolytic potential and microstructures of muscle in broilers were investigated. A total of 105 mixed-sex Arbor Acres broilers were divided into three treatment groups: i) 45-min transport without rest (T group), ii) 45-min transport with 1-h rest (TR group), iii) 45-min transport with 15-min water-misting sprays with forced ventilation and 45-min rest (TWFR group). The results showed the TWFR group significantly increased (p<0.05) initial muscle pH ($pH_i$) and ultimate pH ($pH_u$) and significantly reduced $L^*$ (p<0.05), drip loss, cook loss, creatine kinase, lactate dehydrogenase activity, plasma glucose content, lactate and glycolytic potential when compared with other groups. Microstructure of the muscle from TWFR group broilers under light microscopy showed smaller intercellular spaces among muscle fibers and bundles compared with T group. In conclusion this study indicated water-misting sprays with forced ventilation after transport could relieve the stress caused by transport under high temperature, which was favorable for the broilers' welfare. Furthermore, water-misting sprays with forced ventilation after transport slowed down the postmortem glycolysis rate and inhibited the occurrence of PSE-like meat in broilers. Although rest after transport could also improve the meat quality, the effect was not as significant as water-misting sprays with forced ventilation after transport.