• Title/Summary/Keyword: SMP

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A Task Scheduling Scheme for Bus-Based Symmetric Multiprocessor Systems (버스 기반의 대칭형 다중프로세서 시스템을 위한 태스크 스케줄링 기법)

  • Kang, Oh-Han;Kim, Si-Gwan
    • The KIPS Transactions:PartA
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    • v.9A no.4
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    • pp.511-518
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    • 2002
  • Symmetric Multiprocessors (SMP) has emerged as an important and cost-effective platform for high performance parallel computing. Scheduling of parallel tasks and communications of SMP is important because the choice of a scheduling discipline can have a significant impact on the performance of the system. In this paper, we present a task duplication based scheduling scheme for bus-based SMP. The proposed scheme pre-allocates network communication resources so as to avoid potential communication conflicts. The performance of the proposed scheme has been observed by comparing the schedule length under various number of processors and the communication cost.

Effect of solids retention time on membrane fouling in membrane bioreactors at a constant mixed liquor suspended solids concentration

  • Hao, L.;Liss, S.N.;Liao, B.Q.
    • Membrane and Water Treatment
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    • v.8 no.4
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    • pp.337-353
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    • 2017
  • Membrane fouling at different solids retention times (SRT) (7, 12 and 20 days) was studied under well-controlled conditions in a laboratory-scale aerobic submerged membrane bioreactor under constant biomass concentration using a synthetic high strength wastewater. An increase in SRT was found to improve membrane performance and this correlated to changes in the total production of bound extracellular polymeric substances (EPS), and the composition and properties of bound EPS using X-ray photoelectron spectroscopy (XPS) and Fourier transform-infrared spectroscopy (FTIR) and floc sizes. A larger amount of total bound EPS was found at the lowest SRT (7 days) tested but the ratio of proteins (PN) to carbohydrates (CH) in bound EPS increased with an increase in SRT. Similarly, the quantity of soluble microbial products (SMP) decreased with an increase in SRT and the SMP PN/CH ratio increased with an increase in SRT. SMP concentrations positively correlated to the percentage of membrane pore blocking resistance. The quantity of total bound EPS and total SMP positively corresponded to the membrane fouling rate, while the PN/CH ratio in the bound EPS and SMP negatively correlated to the membrane fouling rate. The results show that both the quantity and composition of bound EPS and SMP and floc sizes are important in controlling membrane fouling.

Trade-off between Resource Efficiency and Fast Protection for Shared Mesh Protection

  • Cho, Choong-hee
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.15 no.7
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    • pp.2568-2588
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    • 2021
  • Shared mesh protection (SMP) protects traffic against failures occurring in a working path, as with linear protection, and allows resource sharing of protection paths with different endpoints. The SMP mechanism coordinates multiple protection paths that require shared resources when failures occur on multiple working paths. When multiple failures occur in SMP networks sharing limited resources, activation can fail because some of the resources in the protection path are already in use. In this case, a node confirming that a resource is not available has the option to wait until the resource is available or to withdraw activation of the protection path. In this study, we recognize that the protection switching time and the number of protected services can be different, depending on which option is used for SMP networks. Moreover, we propose a detailed design for the implementation of SMP by considering options and algorithms that are commonly needed for network nodes. A simulation shows the performance of an SMP system implemented with the proposed design and utilizing two options. The results demonstrate that resource utilization can be increased or protection switching time can be shortened depending on the option selected by the network administrator.

Conditions for Solid Matrix Priming of Carrot Seeds and Physiological Changes in the Seed During the Treatment (당근 종자의 Solid Matrix Priming 적정 조건구명과 처리중 종자의 생리적 변화)

  • Cho, Jeoung-Lai;Lim, Jong-Min;Kang, Sung-Mo;Kang, Jum-Soon
    • Horticultural Science & Technology
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    • v.19 no.4
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    • pp.505-510
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    • 2001
  • To improve germinability of carrot seeds of 'Inari', 'Mansan', 'Mussang', and 'Hongsim' cultivars, various levels of solid matrix priming (SMP) and the physiological changes of seeds associated with SMP were examined. As the ratio of water in a seed-Micro Cel E-water mix and priming duration increased, seed germinability enhanced. However, there was radicle protrusion during SMP in some cultivars, indicating the existence of cultivar different variations of the optimum conditions. The optimum ratio for a seed-Micro Cel E-water mix was 5 : 3 : 10.5. In this mix, the optimum durations for the treatment were 3 days for 'Mansan' and 5 days for other cultivars. SMP at $20^{\circ}C$ to $25^{\circ}C$ resulted in a higher germination percentage and a shorter $T_{50}$. Seeds absorbed water quickly within an hour and the percentage of moisture was stable at 43 to 49 after 24 hours of the treatment. Conductivity of the mix declined for the first 6 hours to $100{\mu}S{\cdot}cm^{-1}$ with little changes thereafter. On the other hand, the pH of the mixed increased slightly during the early phase, and then returned to the initial level as the treatment proceeded.

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The Influence of Excluding No-load Cost from SMP on Cost Reduction Incentive of Generators (계통한계가격(SMP)에서 무부하비용 제외가 발전사 비용절감 유인에 미치는 영향)

  • Kim, Myung Yun;Cho, Sung Bong
    • Environmental and Resource Economics Review
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    • v.23 no.4
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    • pp.617-641
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    • 2014
  • Korean electricity market is a Cost-Based Pool (CBP) designed to minimize electricity production cost through cost by providing cost reduction incentives to generators. Generation companies have shown diverse efforts to reduce costs in CBP market such as procuring low-price fuels, installing high efficiency gas turbine and constructing power plants near the heavy-load site. Recently, as a way to improve CBP market, a proposal to exclude no-load cost from System Marginal Price (SMP) and to compensate generators ex post was suggested to Korea Power Exchange. This study analyzes the impact of excluding no-load cost from SMP on the cost reduction incentive of generators. We found that excluding no-load cost from SMP enhances the likelihood of decreasing the cost reduction incentives of LNG combined-cycle generators lying on the price-setting range.

Solving the Gale-Shapley Problem by Ant-Q learning (Ant-Q 학습을 이용한 Gale-Shapley 문제 해결에 관한 연구)

  • Kim, Hyun;Chung, Tae-Choong
    • The KIPS Transactions:PartB
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    • v.18B no.3
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    • pp.165-172
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    • 2011
  • In this paper, we propose Ant-Q learning Algorithm[1], which uses the habits of biological ants, to find a new way to solve Stable Marriage Problem(SMP)[3] presented by Gale-Shapley[2]. The issue of SMP is to find optimum matching for a stable marriage based on their preference lists (PL). The problem of Gale-Shapley algorithm is to get a stable matching for only male (or female). We propose other way to satisfy various requirements for SMP. ACS(Ant colony system) is an swarm intelligence method to find optimal solution by using phermone of ants. We try to improve ACS technique by adding Q learning[9] concept. This Ant-Q method can solve SMP problem for various requirements. The experiment results shows the proposed method is good for the problem.

Impacts of Energy Tax Reform on Electricity Prices and Tax Revenues by Power System Simulation (전력계통 모의를 통한 에너지세제 개편의 전력가격 및 조세수입에 대한 영향 연구)

  • Kim, Yoon Kyung;Park, Kwang Soo;Cho, Sungjin
    • Environmental and Resource Economics Review
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    • v.24 no.3
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    • pp.573-605
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    • 2015
  • This study proposed scenarios of tax reform regarding taxation on bituminous coal for power generation since July 2015 and July 2014, estimated its impact on SMP, settlement price, tax revenue from year 2015 to year 2029. These scenarios are compared with those of the standard scenario. To estimate them, the power system simulation was performed based on the government plan, such as demand supply program and the customized model to fit Korea's power system and operation. Imposing a tax on bituminous coal for power generation while maintaining tax neutrality reducing tax rate on LNG, the short-term SMP is lowered than the one of the standard scenario. Because the cost of nuclear power generation is still smaller than costs of other power generation, and the nuclear power generation rarely determines SMPs, the taxation impact on SMP is almost nonexistent. Thus it is difficult to slow down the electrification of energy consumption due to taxation of power plant bituminous coal in the short term, if SMP and settlement price is closely related. However, in the mid or long term, if the capacity of coal power plant is to be big enough, the taxation of power plant bituminous coal will increase SMP. Therefore, if the tax reform is made to impose on power plant bituminous coal in the short term, and if the tax rate on LNG is to be revised after implementing big enough new power plants using bituminous coal, the energy demand would be reduced by increasing electric charges through energy tax reform. Both imposing a tax on power plant bituminous coal and reducing tax rate on LNG increase settlement price, higher than the one of the standard scenario. In the mid or long term, the utilization of LNG complex power plants would be lower due to an expansion of generating plants, and thus, the tax rate on LNG would not affect on settlement price. Unlike to the impact on SMP, the taxation on nuclear power plants has increased settlement price due to the impact of settlement adjustment factor. The net impact of energy taxation will depend upon the level of offset between settlement price decrease by the expansion of energy supply and settlement price increase by imposing a tax on energy. Among taxable items, the tax on nuclear power plants will increase the most of additional tax revenue. Considering tax revenues in accordance with energy tax scenarios, the higher the tax rate on bituminous coal and nuclear power, the bigger the tax revenues.

Buckling and free vibration analysis of FG-CNTRC-micro sandwich plate

  • Kolahdouzan, Farzad;Arani, Ali Ghorbanpour;Abdollahian, Mohammad
    • Steel and Composite Structures
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    • v.26 no.3
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    • pp.273-287
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    • 2018
  • Buckling and free vibration analysis of sandwich micro plate (SMP) integrated with piezoelectric layers embedded in orthotropic Pasternak are investigated in this paper. The refined Zigzag theory (RZT) is taken into consideration to model the SMP. Four different types of functionally graded (FG) distribution through the thickness of the SMP core layer which is reinforced with single-wall carbon nanotubes (SWCNTs) are considered. The modified couple stress theory (MCST) is employed to capture the effects of small scale effects. The sandwich structure is exposed to a two dimensional magnetic field and also, piezoelectric layers are subjected to external applied voltages. In order to obtain governing equation, energy method as well as Hamilton's principle is applied. Based on an analytical solution the critical buckling loads and natural frequency are obtained. The effects of volume fraction of carbon nanotubes (CNTs), different distributions of CNTs, foundation stiffness parameters, magnetic and electric fields, small scale parameter and the thickness of piezoelectric layers on the both critical buckling loads and natural frequency of the SMP are examined. The obtained results demonstrate that the effects of volume fraction of CNTs play an important role in analyzing buckling and free vibration behavior of the SMP. Furthermore, the effects of magnetic and electric fields are remarkable on the mechanical responses of the system and cannot be neglected.

3GPP GERAN Evolution System Employing High Order Modulation and Turbo Coding: Symbol Mapping Based on Priority (터보코딩 및 고차변조를 적용하는 3GPP GERAN 진화 시스템: 비트 신뢰도 기반의 심볼 매핑)

  • Oh, Hyeong-Joo;Choi, Byoung-Jo;Hwang, Seung-Hoon;Choi, Jong-Soo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.6A
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    • pp.607-613
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    • 2008
  • In this paper, we investigate the performance of SMP-assisted 3GPP GERAN evolution system employing high order modulation and turbo coding. When applying the SMP which maps systematic bits into highly reliable bit positions, it is confirmed that there is the performance gain for the modulation and coding schemes of 16QAM(DAS-8) as well as 32QAM(DAS-11) by link level simulation.

Relation between sludge properties and filterability in MBR: Under infinite SRT

  • Zhang, Haifeng;Wang, Bing;Yu, Haihuan;Zhang, Lanhe;Song, Lianfa
    • Membrane and Water Treatment
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    • v.6 no.6
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    • pp.501-512
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    • 2015
  • A laboratory-scale submerged membrane bioreactor (MBR) was continuously operated for 100 d at an infinite sludge retention time (SRT) with the aim of identifying possible relation between the filterability of mixed liquor and sludge properties, such as extracellular polymeric substances (EPS), soluble microbial products (SMP), viscosity of mixed liquor, zeta potential of flocs and particle size distributions (PSD). Research results confirmed that MBR can operate with a complete sludge retention ensuring good treatment performances for COD and $NH_3-N$. However, the long term operation (about 40 d) of MBR with no sludge discharge had a negative influence on sludge filterability, and an increase in membrane fouling rates with the time was observed. There as a strong correlation between the sludge filterability and the fouling rate. Among the different sludge properties parameters, the concentration SMP and EPS had a more closely correlation with the sludge filterability. The concentrations of SMP, especially SMP with MW above 10 kDa, had a strong direct correlation to the filterability of mixed sludge. The protein fractions in EPS were biodegradable and available for microorganism metabolism after about 60 days, and the carbohydrates in EPS had a significantly negative effect on sludge filterability in MBR at an infinite SRT.