• Title/Summary/Keyword: Fiber Net

Search Result 215, Processing Time 0.02 seconds

Failure Behavior of Pin-jointed Cylindrical Composites Using Acoustic Emission Technique (AE기법을 이용한 원통형 복합재의 핀 체결부 파괴거동)

  • Yoon, Sung-Ho;Hwang, Young-Eun;Kim, Chan-Gyu
    • Journal of the Korean Society of Propulsion Engineers
    • /
    • v.16 no.4
    • /
    • pp.9-15
    • /
    • 2012
  • In this paper, the bearing strengths and fracture behaviors of the pin-jointed carbon fiber/epoxy composites were investigated through pin loading test with acoustic emission technique. The composites were fabricated by a filament winding process, and three types of laminated patterns were considered. Type 1 was fabricated with stitch, Type 2 was fabricated without stitich and Type 3 was fabricated with prepregs. According to the results, bearing strength of Type 1 was 3.3% lower than that of Type 2 and that of Type 3 was highest. Type 1 and Type 2 revealed a net-tension failure mode, respectively, whereas Type 3 pattern exhibited a bearing failure mode. Also, acoustic emission energy of the Type 3 was higher than that of the Type 1 and Type 2. Therefore, the Type 3 was found to be structurally safer than the Type 1 and Type 2.

Changes in Feed Value of Barley and Pea by Different Seeding Rates and Cutting Dates in Mixed Sowing Cultivation (보리와 완두의 혼파재배에서 혼파비율과 예취시기에 따른 사료가치의 변화)

  • Oh, Tae-Seok;Kim, Chang-Ho;Lee, Hyo-Won
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.54 no.3
    • /
    • pp.279-286
    • /
    • 2009
  • This study carried out to find out feed value of barley plus pea mixture with different ratio and cutting date to got basic information when introduced the mixture as new cropping system in middle part of Korean peninsular. Dry matter (DM) yield increased as barley seeding rate was higher and showed the highest yield in the plots with barley 85% plus 15% ratio when harvested on May 16. There was no different in crude protein, available protein and digestible protein cutting on April 25 in every mixture, but the content increased with higher pea mixture rate after May 2. The content of acid detergent fiber (ADF) and neutral detergent fiber (NDF) increase coincided with higher barley rate and late cutting dates. But relative feed value (RFV) resulted in opposite trend. Higher pea ratio influenced increased content of total digestible nuterients (TDN), but decreased before May 9 cutting and increased after the next cutting regime. There was no statistical difference in P and Mg between sowing rate, but Ca increased at higher pea ratio and P, Ca, K decreased in all plots as harvests were delayed. The content of estimated net energy (ENE), net energy maintenance (NEM) and net energy gain (NEG) significantly increased with higher pea rate and earlier cutting. But net energy lactation (NEL) was no significant differences between seeding rates and cutting dates. In conclusion, mineral yield such as P, Ca, K and Mg showed the highest yield at barley plus pea ratio of 75 : 25 and energy yield of ENE, NEL, NEM, NEG and TDN was the highest at 85 to 15 mixture plots and DM yield, TDN yield, mineral yield such as P, Ca, K and Mg and energy yield of ENE, NEL, NEM, NEG were the highest on each treatment cutting on May 16.

A Study of Efficient Spare Capacity Planning Scheme in Mesh-Based Survivable Fiber-Optic Networks (생존성을 갖는 메쉬기반 광전송망에서의 효율적인 예비용량 설계방안에 관한 연구)

  • Bang, Hyung-Bin;Kim, Byung-Gi
    • The KIPS Transactions:PartC
    • /
    • v.10C no.5
    • /
    • pp.635-640
    • /
    • 2003
  • Due to the development of information technology and widespread use of telecommunications networks, the design of mesh-survivable net works has received considerable attention in recent years. This paper deals with spare capacity planning scheme in mesh-based fiber-optic networks. In this study, a new spare capacity planning scheme is proposed utilizing path restoration with maximal sharing of share capacity that is traced by the spare capacity incremental factor (after this, we called "SCIF"). We compare it with three other spare capacity planning scheme : link capacity of IP (Integer Programming), SLPA(Spare Link Placement Algorithm) and GA(Genetic Algorithm). The approach shows better performance with heuristics algorithm for determining the spare capacity assignment and the computational time is easily controlled allowing the approach to scale to large networks. The major advantages of the new approach are reduction of spare capacity and a polynomial time complexity.omplexity.

Influence of dietary nonstructural carbohydrate concentration on growth performance and carcass characteristics of Holstein steers

  • Ramos-Avina, Daniel;Plascencia, Alejandro;Zinn, Richard
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.31 no.6
    • /
    • pp.859-863
    • /
    • 2018
  • Objective: Since very little information exists about the topic; in this experiment we compare, in a long-term finishing program, the growth-performance responses and carcass characteristics of Holstein steers where non-structural carbohydrate concentration of the diet is reduced from 64% to 51% (dry matter basis). Methods: Sixty Holstein steer calves ($129{\pm}2.2kg$) were blocked by initial weight into five groups and randomly assigned within weight groupings to 10 pens. Calves were fed with a steam-flaked corn-based finishing diets containing 51% higher fiber (HF) or 64% lower fiber (LF) nonstructural carbohydrates. Non-structural carbohydrates concentrations were manipulated substituting dried distiller grain with solubles and alfalfa hay for flaked corn. Cattle were weighed every 112 days and at the end of the experiment (day 308) when the cattle were harvested and carcass characteristics were evaluated. Results: Steers fed the HF diet showed improvement (8.8%) in average daily gain (ADG) during the initial 112-d period. This effect was followed by a numerical trend for greater ADG throughout the remainder of the study so that overall ADG tended to be greater (4.9%, p = 0.06) for the HF than for LF. There were no treatment effects on dry matter intake. Gain efficiency and estimated dietary net energy (NE) were greater 8.3% and 5.2%, respectively for HF during the initial 112-d period. Overall (308-d) gain efficiency and estimated dietary NE were similar for both dietary treatments. However, due to differences in tabular dietary NE, the ratio of observed:expected dietary NE tended to be greater (4.1%, p = 0.06) for the HF vs LF diet. There were no treatment effects on carcass characteristics except for a tendency toward a slightly greater (0.5%, p = 0.09) estimated carcass yield. Conclusion: Reducing the non-structural carbohydrate concentration of a conventional steam-flaked corn-based growing finishing diet for Holstein steers can effectively enhance growth performance, particularly during the early growing and late finishing phases.

Energy Utilization of Growing Chicks in Various Nutritional Conditions

  • Sugahara, Kunio
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.16 no.6
    • /
    • pp.903-909
    • /
    • 2003
  • For the last two decades, energy utilization of growing chicks has been studied more and more. This paper focuses on the energy utilization estimated by the metabolizable energy (ME) values and the efficiency at which ME is used for growth of chicks under various nutritional environment. Degree of saturation of dietary fats is responsible for nitrogen-corrected apparent metabolizable energy (AMEn) of fats. The effect of dietary fat sources on heat production depends on the kind of unsaturated fatty acids as well as the degree of saturation. Medium chain triglyceride shows lower AME and net energy than long chain triglyceride. Phytase as feed additives increases the AME values of the diet along with improvement of the phosphorous utilization. Ostriches have higher ability to metabolize the energy of fiber-rich foodstuffs than fowls. Their higher ability seems to be associated with fermentation of fiber in the hindgut. Proportions of macronutrients in the diets have influenced not only the gain of body protein and energy but also the oxidative phosphorylation of the chicken liver. Essential amino acids deficiency reduces ME/GE (energy metabolizability) little, if any. Growing chicks respond to a deficiency of single essential amino acids with the reduction of energy retained as protein and increased energy retained as fat. Thus, energy retention is proportional to ME intake despite deficiency, and efficiency of ME utilization is not affected by deficiency of amino acids. Effect of oral administration of clenbuterol, a beta-adrenergic agonist, on the utilization of ME varies with the dose of the agents. Although the heat production related to eating behavior has been estimated less than 5% of ME, tube-feeding diets decreases HI by about 30%.

Dynamic Characterization of Backpulsing Hollow Fiber Module System (역충격형 중공사모듈의 동특성 연구)

  • 노수홍;박상현;장진호
    • Membrane Journal
    • /
    • v.11 no.1
    • /
    • pp.14-21
    • /
    • 2001
  • Rapid backpulsing to reduce membrane fouling of hollow fiber ultrafiltration module (polyacrylonitrile with 50000 l'vlWCO, 1.4 rom OD and 0,9 mm ID) was studied with latex solutions. Values estimated by a theoretical model were compared with the ones obtained from the systems with or without backpulsing, Specific Cake resistance, time consUmt for cake growth, diffusion coefficient, and the rate constants of fnur fouling models; the complete, intermediate. standard blocking and cake filtration were calculated to obtain the theoretical values. High frequency backpulsing gave net increase of fluxes by 40~120%. Fluxes predicted by the model were in good agreement with experimental ones within 14% error bound, The optimum backpulsing strength was acquired at 20% in the ranges of 20~40% strength and the optimum frequcncv was acquired at 2 Hz in the ranges of 0.67~3 Hz.

  • PDF

Studies on the Application of Starch for paper surface sizing(III) - The influence of surface sizing treatment with starch on the quality of uncoated printing paper - (종이 표면 사이즈 프레스용 전분의 적용에 관한 연구 -표면 사이즈용 전분이 백상지 품질에 미치는 영향 -)

  • 윤지영;이용규
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.34 no.2
    • /
    • pp.1-12
    • /
    • 2002
  • Starch dissolved in paper-mill wastes, either as a result of poor retention on the paper web or recycling of surface-treated broke, was a major pollutant Laboratory tests were performed by using different kinds of starch as a surface treatment. It was concluded that the use of cationic starch can positively affect the level of starch dissolved in liquid effluents. When cationically modified starches were used for surface sizing, the starch was tightly bound to the paper fibers, it was not removed during the repulping of broke. The result of mill trial in fine paper manufacture for the application of low-viscosity cationic starches used in size press reduced COD load in the effluents and increased One Pass Retention. It had been found that when cationic starch used as a surface sizing agent, more starch was retained on or near the surface of the sheet than with conventional oxidized starches. Thus surface strengths and quality were improved. In addition it is possible to maintain the desired level of starch penetration into the fiber net and improve porosity, opacity and brightness. In contrast, in most cases, dusting problems are notably eliminated. Cationic surface sized starch improved black and color ink-jet print quality in terms of feathering and optical density of the print image. These improved properties were believed to be due to a combination of fiber bonding and surface orientation more uniform starch concentration on the paper surface was resulted. Moreover cationic charges in the paper surface lend themselves excellently to fix ink jet ink anionic in nature.

Determination of Nutrient Contents and In vitro Gas Production Values of Some Legume Forages Grown in the Harran Plain Saline Soils

  • Boga, M.;Yurtseven, S.;Kilic, U.;Aydemir, S.;Polat, T.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.27 no.6
    • /
    • pp.825-831
    • /
    • 2014
  • The aim of this study was to determine the nutritive value of some legume species in salt-affected soils of South-East Anatolian region using chemical composition and in vitro gas production kinetics. In this study, Lotus corniculatus, Trifolium alexandrinum, Medicago sativa were sown and tested in four different locations. A 3 by 4 factorial design with 3 legume species and 4 salt levels (non salty electrical conductivity (EC)<4 dS/m; low salt: 4 dS/m>EC<8 dS/m, medium saline: 8 dS/m>EC<16 dS/m and high salt: 16 dS/m>EC) was used in the study. Results indicated that salinity and plants had no significant effect on ash and ether extract. Dry matter (DM), acid detergent fiber, digestible dry matter, dry matter intake (DMI) were affected by plant, salinity and plant${\times}$salinity interaction. On the other hand neutral detergent fiber, relative feed value (RFV), and DMI were affected by salinity and plant${\times}$salinity interaction. Mineral contents were affected by plant species, salinity and salinity${\times}$plants interactions. In vitro gas production, their kinetics and estimated parameters such as were not affected by salinity whereas the gas production up to 48 h, organic matter digestibility, metabolizable energy (ME), and net energy lactation ($NE_L$) were affected by plant and plant${\times}$salt interaction. Generally RFVs of all species ranged from 120 to 210 and were quite satisfactory in salty conditions. Current results show that the feed value of Medicago sativa is higher compared to Lotus corniculatus and Trifolium alexandrinum.

System Performance Improvements in WDM ($24{\times}40$ Gbps) Transmission using Optical Phase Conjugator and Dispersion Management (WDM ($24{\times}40$ Gbps) 전송에서 광 위상 공액기와 분산 제어를 이용한 시스템 성능 개선)

  • Lee, Seong-Real;Yim, Hwang-Bin
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.33 no.10B
    • /
    • pp.855-864
    • /
    • 2008
  • Optical link techniques compensating chromatic dispersion and nonlinear effects, which affect distortion of optical signals, generated in single mode fiber are investigated through computer simulation and design rule of these link techniques is proposed for implementation of wideband and long-haul WDM ($24{\times}40$ Gbps) transmission system. The optical link consist of dispersion management (DM) compensating the cumulated dispersion through total transmission line and optical phase conjugation in middle of total transmission line for compensating distorted signals by frequency inversion. DM schemes considered in this research are lumped DM and inline DM. It is confirmed that eye opening penalty (EOP) of overall WDM channels are more improved than those in WDM transmission systems with only optical phase conjugator (OPC), if DM is additionally applied to these systems. And, design rule in both DM schemes are proposed by using effective residual dispersion range. It is confirmed that inline DM is better than lumped DM in the improving EOP of total WDM channels and in effective residual dispersion range.

Development of Highly Reliable Power and Communication System for Essential Instruments Under Severe Accidents in NPP

  • Choi, Bo Hwan;Jang, Gi Chan;Shin, Sung Min;Lee, Soo Ill;Kang, Hyun Gook;Rim, Chun Taek
    • Nuclear Engineering and Technology
    • /
    • v.48 no.5
    • /
    • pp.1206-1218
    • /
    • 2016
  • This article proposes a highly reliable power and communication system that guarantees the protection of essential instruments in a nuclear power plant under a severe accident. Both power and communication lines are established with not only conventional wired channels, but also the proposed wireless channels for emergency reserve. An inductive power transfer system is selected due to its robust power transfer characteristics under high temperature, high pressure, and highly humid environments with a large amount of scattered debris after a severe accident. A thermal insulation box and a glass-fiber reinforced plastic box are proposed to protect the essential instruments, including vulnerable electronic circuits, from extremely high temperatures of up to $627^{\circ}C$ and pressure of up to 5 bar. The proposed wireless power and communication system is experimentally verified by an inductive power transfer system prototype having a dipole coil structure and prototype Zigbee modules over a 7-m distance, where both the thermal insulation box and the glass-fiber reinforced plastic box are fabricated and tested using a high-temperature chamber. Moreover, an experiment on the effects of a high radiation environment on various electronic devices is conducted based on the radiation test having a maximum accumulated dose of 27 Mrad.