• 제목/요약/키워드: Fiber-net

검색결과 212건 처리시간 0.036초

Optical Transmission Link with Balanced and Unbalanced Dispersion Distributions and Non-midway Optical Phase Conjugator

  • Chung, Jae-Pil;Lee, Seong-Real
    • Journal of information and communication convergence engineering
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    • 제19권4호
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    • pp.199-204
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    • 2021
  • We propose a dispersion-managed link with a non-midway optical phase conjugator (OPC), in which the residual dispersion per span (RDPS) of each fiber span is different for each transmission section before and after OPC. We numerically demonstrate the compensation for 960-Gb/s wavelength-division multiplexed (WDM) signals distorted by chromatic dispersion and Kerr nonlinearity of the fiber. We consider different cases for non-midway OPC, including six fiber spans - OPC - 14 fiber spans and 14 fiber spans - OPC - 6 fiber spans. The numerical results show that the compensation of the distorted 960 Gb/s WDM is more efficient when the OPC is placed after 6-th fiber span as compared to after the 14-th fiber span. Our simulation results also indicate that the compensation effect increases when the difference in net residual dispersion between both transmission sections is not large, but they are not the same. Under this condition, the larger the magnitude of the RDPSs of each fiber span, the greater the compensation.

The optimum steel fiber reinforcement for prestressed concrete containment under internal pressure

  • Zheng, Zhi;Sun, Ye;Pan, Xiaolan;Su, Chunyang;Kong, Jingchang
    • Nuclear Engineering and Technology
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    • 제54권6호
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    • pp.2156-2172
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    • 2022
  • This paper investigates the optimum fiber reinforcement for prestressed concrete containment vessels (PCCVs) under internal pressure. To achieve this aim, steel fiber, which is the most widely used fiber type in current engineering applications, is adopted to constitute steel fiber-reinforced concrete (SFRC) to substitute the conventional concrete in the PCCV. The effects of characteristic parameters, 𝜆sf, of the steel fiber affecting significantly the mechanical behavior of the concrete are first taken into account. Partial or complete concrete regions of the PCCV are also considered to be replaced by SFRC to balance the economy and safety. By adopting the ABAQUS software, the ultimate bearing capacity and performance for the fiber-reinforced PCCV are scientifically studied and quantified, and the recommendations for the optimum way of fiber reinforcement are presented.

Health monitoring of carbon fiber-reinforced polymer composites in γ-radiation environment using embedded fiber Bragg grating sensors

  • Jing Zhong;Feida Chen;Yuehao Rui;Yong Li;Xiaobin Tang
    • Nuclear Engineering and Technology
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    • 제55권8호
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    • pp.3039-3045
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    • 2023
  • Fiber-reinforced polymer (FRP) composites are considered suitable candidates for structural materials of spacecrafts due to their excellent properties of high strength, light weight, and corrosion resistance. An online health monitoring method for FRP composites must be applied to space structures. However, the application of existing health monitoring methods to space structures is limited due to the harsh space environment. Here, carbon fiber-reinforced polymer (CFRP) composites embedded with fiber Bragg grating (FBG) sensors were prepared to explore the feasibility of strain monitoring using embedded FBG sensors in γ-radiation environment. The analysis of the influence of radiation on the strain monitoring demonstrated that the embedded FBG can be successfully applied to the health monitoring of FRP composites in radiation environment.

Changes of Pulling-out Length and Shrinkage Ratio in Polyester/Spandex Power Net Warp Knitted Fabrics

  • Lee Choon-Gil
    • Fibers and Polymers
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    • 제7권1호
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    • pp.51-56
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    • 2006
  • Power net fabric is one of the highly extensible two-way fabrics. Power net structure shows special characteristics in the wearing of final functional clothes. This research evaluated effects of treatment temperature on proportional extensibility and shrinkage ratio of spandex at a given wale length. As treatment temperature increased, extensibility increased proportionally to the standard length of the sample and the shrinkage ratio in the direction of course and wale increased. The pulling-out length increased proportionally to the standard length of the sample. However it was affected by the effect of treatment time and temperature due to the thermal properties of spandex filament yarn.

The Effect of Source of Dietary Fiber and Starch on Ileal and Fecal Amino Acid Digestibility in Growing Pigs

  • Wang, J.F.;Wang, M.;Lin, D.G.;Jensen, B.B.;Zhu, Yaohong
    • Asian-Australasian Journal of Animal Sciences
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    • 제19권7호
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    • pp.1040-1046
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    • 2006
  • Studies were carried out with a repeated $4{\times}4$ Latin square design with eight cannulated pigs fed four experimental diets to investigate the effect of dietary fiber and starch sources on apparent ileal and fecal amino acid digestibility. Each period lasted 15 d, with diet acclimation from d 1 to 7, feces collection for 48 h on d 8 to 9 and ileal sample collection for 12 h on d 13 to 15. The four experimental diets consisted mainly of cooked rice with the addition of protein sources (CON), partial replacement of cooked rice with either potato starch (PS), sugar beet pulp (SBP) or wheat bran (WB). Chromic oxide was used as an indigestible marker. With the exception of histidine, lysine and tryptophan, no differences were observed in the apparent ileal digestibility of amino acids between diets. The inclusion of potato starch did not affect the ileal and fecal amino acid digestibility. In comparison with diet CON, a decreased (p<0.05) ileal digestibility of histidine was found in pigs fed diet SBP, while the ileal digestibilities of histidine, lysine and tryptophan were decreased (p<0.05) by the inclusion of wheat bran. Inclusion of fiber sources (sugar beet pulp and wheat bran) caused a reduction (p<0.05) in the fecal amino acid digestibility and the net disappearance of amino acids in the large intestine. Of the indispensable amino acids, there was a 'net synthesis' for methionine in the large intestine of pigs when diets were supplemented with dietary fiber. The decrease in fecal amino acid digestibility with the addition of dietary fiber indicates an increase in the synthesis of bacterial protein in the large intestine.

분산 제어와 광 위상 공액이 적용된 광 전송 링크에서 인위적인 분포의 SMF 길이와 RDPS를 통한 WDM 신호의 보상 (Compensation for WDM Signals through Artificial Distribution of SMF Length and RDPS in Optical Links with Dispersion Management and Optical Phase Conjugation)

  • 이성렬
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2012년도 추계학술대회
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    • pp.655-658
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    • 2012
  • 광섬유의 그룹 속도 분산 (GVD; group velocity dispersion)과 비선형 효과의 상호 작용에 의해 왜곡되는 960 Gbps 신호의 보상을 위해 분산 제어 (DM; dispersion management) 기술이 적용된 광전송 링크의 유연한 구성에 필요한 중계 구간 (fiber span)을 구성하는 단일 모드 광섬유 (SMF; single mode fiber)의 길이와 중계 구간 당 잉여 분산 (RDPS; residual dispersion per span)을 인위적으로 분포시킨 구조에서의 전체 잉여 분산 (NRD; net residual dispersion)의 최적치와 최상의 시스템 성능을 얻을 수 있는 분포 패턴을 도출하였다.

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단일 모드 광섬유 전송 링크에 축적된 분산의 precompensation을 통한 40 Gbps의 RZ 전송 (Transmission of 40 Gbps RZ through Precompensation of Dispersion Accumulated in Transmission Links of Single Mode Fibers)

  • 이성렬
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2010년도 추계학술대회
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    • pp.780-783
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    • 2010
  • 단일 모드 광섬유 (SMF; single mode fiber)로 구성된 960 km의 전체 전송 링크에 축적된 분산을 보상하기 위해 inline 분산 제어 (DM; dispersion management)이 적용된 경우에 precompensation만의 조절로 24개의 각기 다른 파장을 갖는 RZ 형식의 신호를 양호하게 전송할 수 있는 전체 잉여 분산량 (NRD; net residual dispersion)을 RZ 형식의 충격 계수와 전송 링크의 중계 거리 당 잉여 분산량 (RDPS; residual dispersion per span)에 따라 도출하였다. 전송 링크의 RDPS가 적을수록 24개 파장 모두의 유효 NRD 범위를 늘릴 수 있고, 동일한 RDPS에서는 RZ 형식의 충격 계수가 증가될수록 유효 NRD 범위가 증가되는 것을 확인하였다.

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어류 가두리에 적용하기 위한 황동 직조 어망의 성능 평가 (Evaluation of brass weaving fishing nets for aquaculture cage applications)

  • 김건우;박수봉
    • 수산해양기술연구
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    • 제60권2호
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    • pp.186-193
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    • 2024
  • Most fishing nets used in fish cage aquaculture are made of synthetic fibers such as polyamide (PA) and polyethylene (PE). Therefore, it is challenging to maintain the internal volume of the fish cage due to biofouling, which can increase the load on the cage or reduce dissolved oxygen levels by impeding smooth current flow. To address this issue, research has been conducted to replace conventional synthetic fiber cage nets with brass nets, demonstrating certain benefits such as improved productivity and ease of fish cage management. However, given the need for a more thorough examination of brass fishing net weaving technology and performance, this study assessed the optimal weaving method for brass fishing nets to be used in fish cages. Additionally, it provided essential data for the practical application of brass fishing nets by evaluating their weight, tensile strength, elongation, fatigue resistance, and wear resistance. The study concluded that weaving brass fishing nets using the chain link method ensures durability, ease of installation, and compact storage in a scroll-like form. Moreover, due to their superior fatigue and wear resistance properties, brass nets can offer increased utility if appropriate net diameter and length are selected to compensate for their higher weight per unit area and relatively higher cost compared to existing fiber fishing nets.

드릴에 의한 탄소섬유강화플라스틱의 절삭특성에 관한 연구 (A Study on the Cutting Characteristics of the Carbon Fiber Reinforced Plastics by Drill Tools)

  • 박종남;정성택;김선진;조규재
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2002년도 추계학술대회 논문집
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    • pp.279-282
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    • 2002
  • With the development of industrial society, the interest of new material is growing even in machining center. Composite materials in the new materials are superior to the metals In measure stability of strength, modulus and heat, moreover when mould is prepared, it can be done net shape manufacturing so it can be used widely in all sorts of machine parts, interior materials of car structural construct ions, the space aerial industry, ship materials, sports goods and so on. Therefore in this study, the property of processing drill on CFRP in composite materials by experimental study and some problems were examined.

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A Distributed Control Architecture for Advanced Testing In Realtime

  • Thoen Bradford K.;Laplace Patrick N.
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 2006년도 학술발표회 논문집
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    • pp.563-570
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    • 2006
  • Distributed control architecture is based on sharing control and data between multiple nodes on a network Communication and task sharing can be distributed between multiple control computers. Although many communication protocols exist, such as TCP/IP and UDP, they do not have the determinism that realtime control demands. Fiber-optic reflective shared memory creates the opportunity for realtime distributed control. This architecture allows control and computational tasks to be divided between multiple systems and operate in a deterministic realtime environment. One such shared memory architecture is based on Curtiss-Wright ScramNET family of fiber-optic reflective memory. MTS has built seismic and structural control software and hardware capable of utilizing ScramNET shared memory, opening up infinite possibilities in research and new capabilities in Hybrid and Model-In-The-Loop control.

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