• Title/Summary/Keyword: fibre

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An Efficient Recovery Technique using Global Buffer on SAN Environments (SAN 환경에서의 전역 버퍼를 이용한 효율적인 회복 기법)

  • Park, Chun-Seo;Kim, Gyeong-Bae;Lee, Yong-Ju;Park, Seon-Yeong;Sin, Beom-Ju
    • The KIPS Transactions:PartA
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    • v.8A no.4
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    • pp.375-384
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    • 2001
  • The shared disk file systems use a technique known as file system journaling to support recovery of metadata on the SAN(Storage Area Network). In the existing journaling technique, the metadata that is dirtied by one host must be updated to disk space before some hosts access it. The system performance is decreased because the disk access number is increased. In this paper, we describe a new recovery technique using a global buffer to decrease disk I/O. It transmits the dirtied metadata into the other hosts through Fibre Channel network on the SAN instead of disk I/O and supports recovery of a critical data by journaling a data as well as metadata.

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Metadata Management of a SAN-Based Linux Cluster File System (SAN 기반 리눅스 클러스터 파일 시스템을 위한 메타데이터 관리)

  • Kim, Shin-Woo;Park, Sung-Eun;Lee, Yong-Kyu;Kim, Gyoung-Bae;Shin, Bum-Joo
    • The KIPS Transactions:PartA
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    • v.8A no.4
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    • pp.367-374
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    • 2001
  • Recently, LINUX cluster file systems based on the storage area network (SAN) have been developed. In those systems, without using a central file server, multiple clients sharing the whole disk storage through Fibre Channel can freely access disk storage and act as file servers. Accordingly, they can offer advantages such as availability, load balancing, and scalability. In this paper, we describe metadata management schemes designed for a new SAN-based LINUX cluster file system. First, we present a new inode structure which is better than previous ones in disk block access time. Second, a new directory structure which uses extendible hashing is described. Third, we describe a novel scheme to manage free disk blocks, which is suitable for very large file systems. Finally, we present how we handle metadata journaling. Through performance evaluation, we show that our proposed schemes have better performance than previous ones.

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Fabrication of Porous 3-Dimensional Ti Scaffold and Its Bioactivity by Alkali Treatment (다공성 3차원 Ti 지지체의 제조 및 알카리처리에 따른 생체활성 평가)

  • An, Sang-Hyun;Kim, Seung-Eon;Kim, Kyo-Han;Yun, Hui-Suk;Hyun, Yong-Taek
    • Korean Journal of Materials Research
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    • v.19 no.7
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    • pp.362-368
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    • 2009
  • Ti scaffolds with a three-dimensional porous structure were successfully fabricated using powder metallurgy and modified rapid prototyping (RP) process. The fabricated Ti scaffolds showed a highly porous structure with interconnected pores. The porosity and pore size of the scaffolds were in the range of 66$\sim$72% and $300\sim400\;\mu$m, respectively. The sintering of the fabricated scaffolds under the vacuum caused the Ti particles to bond to each other. The strength of the scaffolds depended on the layering patterns. The compressive strength of the scaffolds ranged from 15 MPa to 52 MPa according to the scaffolds' architecture. The alkali treatment of the fabricated scaffolds in an aqueous NaOH solution was shown to be effective in improving the bioactivity. The surface of the alkali-treated Ti scaffolds had a nano-sized fibre-like structure. The modified surface showed a good apatite forming ability. The apatite was formed on the surface of the alkali treated Ti scaffolds within 1 day. The thickness of the apatite increased when the soaking time in a simulated body fluid (SBF) solution increased. It is expected that the surface modification of Ti scaffolds by alkali treatment could be effective in forming apatites in vivo and can subsequently enhance bone formation.

Failure of RC Slabs Strengthened with CFRP Plate (탄소섬유판으로 보강한 철근콘크리트 슬래브의 파괴)

  • Kim, Joong-Koo
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.3 no.3
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    • pp.245-251
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    • 1999
  • Carbon fibre reinforced plastic(CFRP) plate is one of the alternative materials for strengthening of reinforced and prestressed concrete members due to excellent strength and light weight. In this paper, the behavior of slabs strengthened with CFRP plate is observed and analyzed from the test results. Especially specimens with thick plate is tested when large moment and large shear force appear in same position. The failure mode is a peeling-off of the CFRP plate due to flexural-shear crack. This is observed near the loading points with thick plates. Because of this failure mode, thickness of CFRP plates does not influence on the failure loads. Depending on the loading pattern, it is necessary to consider different design criteria for reinforced concrete members with external reinforcement. When large moment and large shear force appear in same location, maximum thickness may limit to 0.6mm and ratio between moment of strengthened slab and moment of unstrengthened slab is proposed 1.5-2.0.

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Nitrate supplementation of rations based on rice straw but not Pangola hay, improves growth performance in meat goats

  • Paengkoum, Siwaporn;Khotsakdee, Jiravan;Paengkoum, Pramote;Schonewille, Thomas;Yuangklang, Chalermpon
    • Animal Bioscience
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    • v.34 no.6
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    • pp.1022-1028
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    • 2021
  • Objective: Supplemental nitrate is known to be an effective tool to mitigate methane emission by ruminants. Based on theoretical considerations, supplemental nitrate can improve but also deteriorate the growth performance. The overall effect of supplemental nitrate on growth performance, however, is not yet known. The objective of the current study was therefore to evaluate the effect of a higher dose of NO3- on overall growth performance when feeding either Pangola grass hay or rice straw. Methods: Thirty-two crossbred, 3-month-old Thai native×Anglo-Nubian crossbred male goats were used. The experiment had a 2×2 factorial design with an experimental period of 60 days. Eight goats were randomly allocated to each dietary treatment, i.e. a ration containing either Pangola hay (Digitaria eriantha Steud) or rice straw (Oryza Sativa) as a source of roughage, supplemented with a concentrate containing either 3.2% or 4.8% potassium nitrate. The rations were formulated to be isonitrogenous. The animals were weighed at the start of the experiment and at days 30 and 60. Feces were collected during the last five days of each 30-day period. Results: High-nitrate increased overall DM intake by approximately 3%, irrespective the source of roughage, but only the goats fed a rice straw-based ration responded with an increase in body weight (BW). Thus, the overall feed conversion ratio (kg feed/kg BW gain) was influenced by roughage source ×nitrate and decreased by almost 60% when the goats were fed rice straw in combination with a high versus a low dietary nitrate content. The digestibility of macronutrients was only affected by the source of roughage and the digestibility of organic matter, crude protein, and neutral detergent fibre was greater when the goats were fed Pangola hay. Conclusion: It was concluded that the replacement of soybean meal by nitrate improves the growth performance of meat goats fed rations based on rice straw, but not Pangola hay.

Study on Thermal Load Capacity of Transmission Line Based on IEEE Standard

  • Song, Fan;Wang, Yanling;Zhao, Lei;Qin, Kun;Liang, Likai;Yin, Zhijun;Tao, Weihua
    • Journal of Information Processing Systems
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    • v.15 no.3
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    • pp.464-477
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    • 2019
  • With the sustained and rapid development of new energy sources, the demand for electric energy is increasing day by day. However, China's energy distribution is not balanced, and the construction of transmission lines is in a serious lag behind the improvement of generating capacity. So there is an urgent need to increase the utilization of transmission capacity. The transmission capacity is mainly limited by the maximum allowable operating temperature of conductor. At present, the evaluation of transmission capacity mostly adopts the static thermal rating (STR) method under severe environment. Dynamic thermal rating (DTR) technique can improve the utilization of transmission capacity to a certain extent. In this paper, the meteorological parameters affecting the conductor temperature are analyzed with the IEEE standard thermal equivalent equation of overhead transmission lines, and the real load capacity of 220 kV transmission line is calculated with 7-year actual meteorological data in Weihai. Finally, the thermal load capacity of DTR relative to STR under given confidence is analyzed. By identifying the key parameters that affect the thermal rating and analyzing the relevant environmental parameters that affect the conductor temperature, this paper provides a theoretical basis for the wind power grid integration and grid intelligence. The results show that the thermal load potential of transmission lines can be effectively excavated by DTR, which provides a theoretical basis for improving the absorptive capacity of power grid.

Anticancer activities of Papaya (Carica papaya): A Review

  • Parray, Zahoor ahmad;Parray, Shabir ahmad;Khan, Javed ahmad;Zohaib, Sharique;Nikhat, Shagufta
    • CELLMED
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    • v.8 no.4
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    • pp.20.1-20.5
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    • 2018
  • Cancer is considered one of the deadly diseases in the world. According to WHO cancer now causes more deaths than all coronary heart disease. The incidence and mortality of the worldwide major cancers are now available in the GLOBOCAN series of the International Agency for Research on Cancer. The transition of global demographic and epidemiologic shows that burden of cancer will increase particularly in low and middle income countries, with over 20 million new cancer cases expected annually as early as 2025. Medicinal plants made known to be prospective and useful job for the treatment of several diseases and disorders from prehistoric days to nowadays. One of the commonly used plants, which have supporting evidences from the recent scientific data for the different types of cancers, is Carica papaya. Papaya (Carica papaya) is widely used as folk caloric herbal medicine, being a powerhouse of nutrients and accessible throughout the year. It is a rich source of three powerful antioxidants, the minerals, vitamins and contains high content of fibre. Carica papaya has provided many remedies for various diseases from ancient days to nowadays, and is regarded as a Nutraceutical. Because of this comprehensive medicinal value of Carica papaya, we are trying here to convey the reports studied especially for the anticancer activities of the age-old fruit, which will help researchers to pull in concert data and may be a "lead" for the one of the dangerous disease in the world.

Strength Characterisation of Composite Securement Device in the Vehicle by FE Analysis (유한요소해석을 통한 차량내 복합재 휠체어 고정구의 구조 강도 특성 평가)

  • Ham, Seok-Woo;Yang, Dong-Gyu;Son, Seung-Neo;Eo, Hyo-Kyoung;Kim, Gyeong-Seok;Cheon, Seong S.
    • Composites Research
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    • v.32 no.4
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    • pp.171-176
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    • 2019
  • In this paper, the strength of the composite securement device was characterised by FE analysis. Preliminary frontal crash analysis for the vehicle, equipped with the conventional steel securement device, was carried out according to the ISO 10542 for special transportation to obtain loading data, which were applied to securement device during crash. The securement device consists of block, guide and rail and the weight fraction of rail was the highest among them, therefore, it is desirable to reduce weight of rail by applying carbon/epoxy composite. Also, it was found that 27% of lightweight effect was obtained by hybrid rail that bottom part was replaced by a composite compared to the conventional rail, i.e., made of SAPH 440, without sacrificing the structural strength.

Effects of lactic acid bacteria and molasses on fermentation dynamics, structural and nonstructural carbohydrate composition and in vitro ruminal fermentation of rice straw silage

  • Zhao, Jie;Dong, Zhihao;Li, Junfeng;Chen, Lei;Bai, Yunfeng;Jia, Yushan;Shao, Tao
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.6
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    • pp.783-791
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    • 2019
  • Objective: This study was to evaluate the fermentation dynamics, structural and nonstructural carbohydrate composition and in vitro gas production of rice straw ensiled with lactic acid bacteria and molasses. Methods: Fresh rice straw was ensiled in 1-L laboratory silos with no additive control (C), Lactobacillus plantarum (L), molasses (M) and molasses+Lactobacillus plantarum (ML) for 6, 15, 30, and 60 days. After storage, the silages were subjected to microbial and chemical analyses as well as the further in vitro fermentation trial. Results: All additives increased lactic acid concentration, and reduced pH, dry matter (DM) loss and structural carbohydrate content relative to the control (p<0.05). The highest organic acid and residual sugar contents and lignocellulose reduction were observed in ML silage. L silage had the highest V-score with 88.10 followed by ML silage. L and ML silage improved in vitro DM digestibility as compared with other treatments, while in vitro neutral detergent fibre degradability (IVNDFD) was increased in M and ML silage (p<0.05). M silage significantly (p<0.05) increased propionic acid (PA) content and decreased butyric acid content and acetic acid/PA as well as 72-h cumulative gas production. Conclusion: The application of ML was effective for improving both the fermentation quality and in vitro digestibility of rice straw silage. Inclusion with molasses to rice straw could reduce in vitro ruminal gas production.

Temporal and spatial variability in the nutritive value of pasture vegetation and supplement feedstuffs for domestic ruminants in Western Kenya

  • Onyango, Alice Anyango;Dickhoefer, Uta;Rufino, Mariana Cristina;Butterbach-Bahl, Klaus;Goopy, John Patrick
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.5
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    • pp.637-647
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    • 2019
  • Objective: The study aimed at quantifying seasonal and spatial variations in availability and nutritive value of herbaceous vegetation on native pastures and supplement feedstuffs for domestic ruminants in Western Kenya. Methods: Samples of herbaceous pasture vegetation (n = 75) and local supplement feedstuffs (n = 46) for cattle, sheep, and goats were collected in 20 villages of three geographic zones (Highlands, Mid-slopes, Lowlands) in Lower Nyando, Western Kenya, over four seasons of one year. Concentrations of dry matter (DM), crude ash (CA), ether extract (EE), crude protein (CP), neutral detergent fibre (NDF), gross energy (GE), and minerals were determined. Apparent total tract organic matter digestibility (dOM) was estimated from in vitro gas production and proximate nutrient concentrations or chemical composition alone using published prediction equations. Results: Nutrient, energy, and mineral concentrations were 52 to 168 g CA, 367 to 741 g NDF, 32 to 140 g CP, 6 to 45 g EE, 14.5 to 18.8 MJ GE, 7.0 to 54.2 g potassium, 0.01 to 0.47 g sodium, 136 to 1825 mg iron, and 0.07 to 0.52 mg selenium/kg DM. The dOM was 416 to 650 g/kg organic matter but differed depending on the estimation method. Nutritive value of pasture herbage was superior to most supplement feedstuffs, but its value strongly declined in the driest season. Biomass yields and concentrations of CP and potassium in pasture herbage were highest in the Highlands amongst the three zones. Conclusion: Availability and nutritive value of pasture herbage and supplement feedstuffs greatly vary between seasons and geographical zones, suggesting need for season- and region-specific feeding strategies. Local supplement feedstuffs partly compensate for nutritional deficiencies. However, equations to accurately predict dOM and improved knowledge on nutritional characteristics of tropical ruminant feedstuffs are needed to enhance livestock production in this and similar environments.