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Availability of Antimalarial Medicines in Community Pharmacies of Lusaka District, Zambia: Implications on Compliance to Malaria Treatment Guidelines
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作者 Tadious Chimombe Steward Mudenda +6 位作者 Stephen Bwalya Tamara N’gona Christabel Nang’andu Hikaambo Webrod Mufwambi Audrey Hamachila Simon Nkowani Busiku Hamainza 《Pharmacology & Pharmacy》 2023年第4期85-97,共13页
Background: Malaria remains a major cause of morbidity and mortality in Zambia, affecting all levels of society, with children under the age of five and pregnant women being most at risk of serious illness. The availa... Background: Malaria remains a major cause of morbidity and mortality in Zambia, affecting all levels of society, with children under the age of five and pregnant women being most at risk of serious illness. The availability of antimalarial medicines is one of the key interventions of malaria management. This study assessed the availability of antimalarial medicines in community pharmacies in Lusaka district, Zambia. Materials and Methods: This was a cross-sectional study that was conducted among 210 community pharmacies from September to November 2022 using a well-structured checklist in selected areas of Lusaka district. The availability was verified by a physical check of the product. The checklist contained the medicines listed both in the guidelines for diagnosis and treatment of malaria in Zambia as well as in the World Health Organization (WHO) malaria treatment guidelines. Results: This study found that all antimalarials listed in the local treatment guidelines for malaria were available in community pharmacies, though with the varying distribution. Of the 210 community pharmacies, 209 (99.5%) had artemether/lumefantrine in stock. The lowest available antimalarial was quinine/clindamycin, which was only available in 3 (1.4%) of the outlets. Conversely, 3 out of 16 (18.8%) antimalarials that were available in community pharmacies were not listed in the local treatment guidelines of malaria in Zambia, despite being listed in the WHO malaria treatment guidelines. This translated into a compliance level of 81.2% based on the local malaria treatment guidelines. Conclusion: This study concluded that antimalarials were available for all categories of malaria management in community pharmacies, though with a varying distribution. The presence of antimalarials not listed in the Zambian treatment guidelines is of public health concern which may have an impact on antimicrobial resistance in the future. 展开更多
关键词 ANTIMALARIALS Antimalarial Medicines availability Community Pharmacies Zambia
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Wave Energy Resource Availability Assessment in the Philippines Based on 30-Year Hindcast Data
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作者 WANG Zhifeng JIANG Dong +1 位作者 DONG Sheng GONG Yijie 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第2期349-364,共16页
With the goal of evaluating the wave and wave energy conditions in the Philippines,the simulated wave nearshore(SWAN)model was used to estimate the wavefield using 30 years of cross-calibrated multi-platform(CCMP)wind... With the goal of evaluating the wave and wave energy conditions in the Philippines,the simulated wave nearshore(SWAN)model was used to estimate the wavefield using 30 years of cross-calibrated multi-platform(CCMP)wind field data(1987-2016).The spatiotemporal patterns of annual and monthly averaged significant wave heights and wave energy in the Philippines were analyzed based on the simulated data.Results showed that they had similar values;in particular,significant wave heights and wave energy were smaller in the south and southwest and higher in the north and northeast.A total of 12 representative points along the Philippine coast were selected to draw wave and wave energy roses.A directional analysis showed that the dominant wave was in the north north-east(NNE),northeast(NE),and east north-east(ENE)directions.Wave energy was mainly distributed in regions with an energy period between 1 and 10 s and significant wave heights between 0 and 4 m.To better utilize wave energy data in the Philippines,this paper studied the available and rich area of wave energy and analyzed the annual and monthly variability index of wave energy in the country.Moreover,the available significant wave heights of wave energy conversion devices(WECs)were set as 0.5-4 m,and the maximum annual average available wave energy occurred in the eastern Philippine Sea area,reaching 13 kW m^(-1).For the safety of WECs,extreme typhoon-induced wave conditions must be considered.Furthermore,the results showed that the maximum significant wave height and mean period over the 50-year return period reached 18 m and 15 s,respectively. 展开更多
关键词 wave energy resource wave energy availability wave climate extreme parameters
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Diverse functions of GmNLA1 members in controlling phosphorus homeostasis highlight coordinate response of soybean to nitrogen and phosphorus availability
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作者 Ming Zhou Yaxue Li +3 位作者 Xing Lu Panmin He Cuiyue Liang Jiang Tian 《The Crop Journal》 SCIE CSCD 2023年第4期1251-1260,共10页
Nitrogen(N) and phosphorus(P) are two essential mineral nutrients for plant growth,which are required in relative high amount in plants.Plants have evolved a series of strategies for coordinately acquiring and utilizi... Nitrogen(N) and phosphorus(P) are two essential mineral nutrients for plant growth,which are required in relative high amount in plants.Plants have evolved a series of strategies for coordinately acquiring and utilizing N and P.However,physiological and molecular mechanisms underlying of N and P interactions remain largely unclear in soybean(Glycine max).In this study,interactions of N and P were demonstrated in soybean as reflected by significant increases of phosphate(Pi) concentration in both leaves and roots by N deficiency under Pi sufficient conditions.A total of four nitrogen limitation adaptation(NLA),encoding RING-type E3 ubiquitin ligase were subsequently identified in soybean genome.Among them,transcription of Gm NLA1-1 and Gm NLA1-3 was decreased in soybean by N starvation under Pi sufficient conditions,not for Gm NLA1-2.Suppression of all three Gm NLA1 members was able to increase Pi concentration regardless of the P and N availability in the growth medium,but decrease fresh weight under normal conditions in soybean hairy roots.However,comparted to changes in control lines at two N levels,N deficiency only resulted in a relatively higher increase of Pi concentration in Gm NLA1-1 or Gm NLA1-3 suppression lines,strongly indicating that Gm NLA1-1 and Gm NLA1-3 might regulate P homeostasis in soybean response to N starvation.Taken together,our result suggest that redundant and diverse functions present in Gm NLA1 members for soybean coordinate responses to P and N availability,which mediate P homeostasis. 展开更多
关键词 GmNLA1 N availability P deficiency P homeostasis SOYBEAN
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Health Data Availability Protection:Delta-XOR-Relay Data Update in Erasure-Coded Cloud Storage Systems
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作者 Yifei Xiao Shijie Zhou 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第4期169-185,共17页
To achieve the high availability of health data in erasure-coded cloud storage systems,the data update performance in erasure coding should be continuously optimized.However,the data update performance is often bottle... To achieve the high availability of health data in erasure-coded cloud storage systems,the data update performance in erasure coding should be continuously optimized.However,the data update performance is often bottlenecked by the constrained cross-rack bandwidth.Various techniques have been proposed in the literature to improve network bandwidth efficiency,including delta transmission,relay,and batch update.These techniques were largely proposed individually previously,and in this work,we seek to use them jointly.To mitigate the cross-rack update traffic,we propose DXR-DU which builds on four valuable techniques:(i)delta transmission,(ii)XOR-based data update,(iii)relay,and(iv)batch update.Meanwhile,we offer two selective update approaches:1)data-deltabased update,and 2)parity-delta-based update.The proposed DXR-DU is evaluated via trace-driven local testbed experiments.Comprehensive experiments show that DXR-DU can significantly improve data update throughput while mitigating the cross-rack update traffic. 展开更多
关键词 Data availability health data data update cloud storage IoT
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Study of Optimal Frequency to the Repairable System Due to Failure Finding Interval to Maximize Availability System
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作者 Emmanuel Hagenimana Charline Uwilingiyimana Umuraza Clarisse 《Journal of Applied Mathematics and Physics》 2023年第6期1795-1805,共11页
This research article is based on a study of optimal frequency to the repairable system due to the failure finding interval to maximize as well as minimize the availability of some components devices. We studied toget... This research article is based on a study of optimal frequency to the repairable system due to the failure finding interval to maximize as well as minimize the availability of some components devices. We studied together maintenance and corrective actions that carried out item of failure and periodic failure finding designed to check whether a system is still working. The model is proved as well as useful application in detecting the problem related to finding failure tasks of different scheme devices by maximization. The model formulated and the numerical application to the relevant mathematical model have been discussed to demonstrate the article quality. Therefore based on probability analytic development, the optimal maintenance policy is then obtained as solution of an optimization problem in which the maintenance cost rate is the objective function and the risk of corrective maintenance is the constraint function. Finally, the solution to the optimal device in the considered development model has been well adjusted due to derivation to the experimental observation rather than theory which will be taken into consideration in the next applied practical design research related and the system device provided that, the proactive device agreed with using the exponential distribution to the survive distribution function which can not be considered as valid. 展开更多
关键词 Maximization Failure Interval Repairable System Inspection Interval availability System Optimal Inspection
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Research and Practice on High Availability Scheme of Unified Identity Authentication System Based on CAS in Colleges and Universities
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作者 Man Liu Lei Yu 《Journal of Information Security》 2023年第1期16-24,共9页
Unified identity authentication has become the basic information service provided by colleges and universities for teachers and students. Security, stability, high concurrency and easy maintenance are our requirements... Unified identity authentication has become the basic information service provided by colleges and universities for teachers and students. Security, stability, high concurrency and easy maintenance are our requirements for a unified identity authentication system. Based on the practical work experience of China University of Geosciences (Beijing), this paper proposes a high availability scheme of unified identity authentication system based on CAS, which is composed of multiple CAS Servers, Nginx for load balancing, and Redis as a cache database. The scheme has been practiced in China University of Geosciences (Beijing), and the application effect is good, which has practical reference significance for other universities. 展开更多
关键词 Unified Identity Authentication CAS REDIS High availability Colleges and Universities
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Heavy metal availability and impact on activity of soil microorganisms along a Cu/Zn contamination gradient 被引量:21
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作者 WANG Yuan-peng SHI Ji-yan +2 位作者 LIN Qi CHEN Xin-cai CHEN Ying-xu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第7期848-853,共6页
All the regulations that define a maximum concentration of metals in the receiving soil are based on total soil metal concentration. However, the potential toxicity of a heavy metal in the soil depends on its speciati... All the regulations that define a maximum concentration of metals in the receiving soil are based on total soil metal concentration. However, the potential toxicity of a heavy metal in the soil depends on its speciation and availability. We studied the effects of heavy metal speciation and availability on soil microorganism activities along a Cu/Zn contamination gradient. Microbial biomass and enzyme activity of soil contaminated with both Cu and Zn were investigated. The results showed that microbial biomass was negatively affected by the elevated metal levels. The microbial biomass-C (Cmic)/organic C (Corg) ratio was closely correlated to heavy metal stress. There were negative correlations between soil microbial biomass, phosphatase activity and NH4NO3 extractable heavy metals. The soil microorganism activity could be predicted using empirical models with the availability of Cu and Zn. We observed that 72% of the variation in phosphatase activity could be explained by the NH4NO3-extractable and total heavy metal concentration. By considering different monitoring approaches and different viewpoints, this set of methods applied in this study seemed sensitive to site differences and contributed to a better understanding of the effects of heavy metals on the size and activity of microorganisms in soils. The data presented demonstrate the relationship between heavy metals availability and heavy metal toxicity to soil microorganism along a contamination gradient. 展开更多
关键词 heavy metals availability SPECIATION ACTIVITY soil microorganism
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Phenotypic plasticity in response to soil moisture availability in the clonal plant Eremosparton songoricum (Litv.) Vass. 被引量:6
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作者 JianCheng WANG Xiang SHI +1 位作者 DaoYuan ZHANG LinKe YIN 《Journal of Arid Land》 SCIE 2011年第1期34-39,共6页
Eremosparton songoricum (Litv.) Vass is a dwarf clonal shrubby legume developed on the windward slopes of mobile or semi-fixed sand dunes of Central Asia. It is assumed that E. songoricum must possess a high degree ... Eremosparton songoricum (Litv.) Vass is a dwarf clonal shrubby legume developed on the windward slopes of mobile or semi-fixed sand dunes of Central Asia. It is assumed that E. songoricum must possess a high degree of phenotypic plasticity for such a heterogeneous habitat. The variations of E. songoricum plants growing in two typical microhabitats (the upper slope and the lower slope of semi-mobile dune) were investigated. The morphological characteristics and the biomass allocation patterns were measured and compared at the clonal fragment level. Compared with the clonal fragment on the lower slope of dune, the clonal fragment on the upper slope of the dune (a) declined in total biomass and ramet height, (b) increased the length of rhizomes and the number of roots, (c) increased the degree of asym- metry, and (d) heightened allocation to the belowground biomass. Our results confirmed the hypothesis of high phenotypic adjustment capacity of E. songoricum to habitat moisture availability. Phenotypic plasticity of E. songoricum contributed to reduce the damage risk, led to an environmentally induced specialization in function of resources exploitation, resulted in its persistence in heterogeneous environments and was adaptive in sand dune environment. 展开更多
关键词 Eremosparton songoricum moisture availability phenotypic plasticity sand dune
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THE AVAILABILITY OF DISSOLVED ORGANIC PHOSPHORUS COMPOUNDS TO MARINE PHYTOPLANKTON 被引量:3
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作者 洪华生 王海黎 黄邦钦 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1995年第2期169-176,共8页
The availability of three dissolved organic phosphorus (DOP) compounds as nutrient sources for experimentalcultare of three algae was studied. Results indicated that these compounds could be utilized byalgae, and th... The availability of three dissolved organic phosphorus (DOP) compounds as nutrient sources for experimentalcultare of three algae was studied. Results indicated that these compounds could be utilized byalgae, and that dissolved inorganic phosphorus (DIP) was first to be uptaken when various forms ofphosphorus (DIP and DOP) co-existed. Dicrateria zhanjiangensis’ uptake of sodium glycerophosphatewas faster than that of D-ribose-5-phosphate. The increase of sodium glycerphosphate had little effecton the maximum uptake rate(V<sub>max</sub>) of Chlorella sp., but increased the semisaturation constant(K<sub>s</sub>) remarkably;the photosynthesis rates(PR) of Dicrateria zhanjiangensis and Chlorella sp. were rarely affected byusing various forms of phosphorus in the culture experiments. The possible DOP pathways utilizedby algae are discussed. 展开更多
关键词 DOP COMPOUNDS availability MARINE ALGAE CULTURE experiment
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Rhizosphere soil bacterial community composition in soybean genotypes and feedback to soil P availability 被引量:3
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作者 ZHOU Tao WANG Li +5 位作者 DU Yong-li LIU Ting LI Shu-xian GAO Yang LIU Wei-guo YANG Wen-yu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第10期2230-2241,共12页
Soil with low phosphorus (P) availability and organic matter contents exists in large area of southwest of China, but some soybean genotypes still show well adaptations to this low yield farmland. However, to date, th... Soil with low phosphorus (P) availability and organic matter contents exists in large area of southwest of China, but some soybean genotypes still show well adaptations to this low yield farmland. However, to date, the underlying mechanisms of how soybean regulates soil P availability still remains unclear, like microbe-induced changes. The objective of the present study was to compare the differences of rhizosphere bacterial community composition between E311 and E109 in P-sufficiency (10.2 mg kg^-1) and P-insufficiency (5.5 mg kg^-1), respectively, which then feedback to soil P availability. In P-sufficiency, significant differences of the bacterial community composition were observed, with fast-growth bacterial phylum Proteobacteria, genus Dechloromonas, Pseudomonas, Massilia, and Propionibacterium that showed greater relative abundances in E311 compared to E109, while in P-insufficiency were not. A similar result was obtained that E311 and E109 were clustered together in P-insufficiency rather than in P-sufficiency by using principal component analysis and hierarchical clustering analysis. The quadratic relationships between bacterial diversity and soil P availability in rhizosphere were analyzed, confirming that bacterial diversity enhanced the soil P availability. Moreover, the high abundance of Pseudomonas and Massilia in the rhizosphere of E311 might increased the P availability. In the present study, the soybean E311 showed capability of shaping rhizosphere bacterial diversity, and subsequently, increasing soil P availability. This study provided a strategy for rhizosphere management through soybean genotype selection and breeding to increase P use efficiency, or upgrade middle or low yield farmland. 展开更多
关键词 SOYBEAN low P RHIZOSPHERE BACTERIAL community SOIL P availability
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Availability Analysis of Parallel Repairable System with Omitted Failures 被引量:3
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作者 郑治华 崔利荣 《Journal of Beijing Institute of Technology》 EI CAS 2009年第1期117-120,共4页
The new model for parallel repairable system is introduced, and it is based on the practice problems of maintenance and the idea of Ion-Channel modeling. In the new model, repair times that are sufficiently short (le... The new model for parallel repairable system is introduced, and it is based on the practice problems of maintenance and the idea of Ion-Channel modeling. In the new model, repair times that are sufficiently short (less than some critical value) do not result in system failure, and such a repair interval is omitted from the downtime record. Usually, the underlying process is Markov process if the durations of working and repair time have the negative-exponential distributions, but the new system has not the Markov properties, which is worth to study. The reliability indexes such as instantaneous availability and steady-state availabilities for the new system are given through probability analysis. A numerical example is given to illustrate the results. 展开更多
关键词 parallel repairable system Markov process availability omitted failure
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Effects of Different Oligosaccharides on Performance and Availability of Nutrients in Broilers 被引量:3
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作者 GAOYing SHANAn-shan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2004年第1期37-41,共5页
One hundred and forty-four Avin broilers (1 d of age) were randomly divided into six groups, with three replicates of eight birds each to study on the effects of different oligosaccharides on performance and availabil... One hundred and forty-four Avin broilers (1 d of age) were randomly divided into six groups, with three replicates of eight birds each to study on the effects of different oligosaccharides on performance and availability of nutrients in broilers. The control group(Group I)was fed with corn-soybean meal as basal diet, and the trial groups (Group II, III, IV,V and VI) were fed with basal diet plus 0.1% Manoligosaccharides(MOS), 0.3% Soybean-Oligosaccharides(SBOS), 0.3% Fructo-oligosaccharides(FOS), 0.3% α-Glucooligosaccharides(α-GOS) and 50 mg·L-1 Chlortetracycline(CTC), respectively. The results showed that the supplementation of oligosaccharides slightly improved daily gain and feed intake. SBOS supplementation improved, but MOS and α-GOS significantly decreased availability of energy. Oligosaccharides supplementation improved availability of energy, phosphorus, calcium, magnesium and iron, and significantly increased cholesterol content of fecal, and did not affect on availability of protein and cholesterol contents in serum and muscle. Availability of phosphorus of broilers fed with FOS was much higher than that with α-GOS. SBOS supplementation remarkably increased availability of iron. 展开更多
关键词 OLIGOSACCHARIDES PERFORMANCE availability of nutrients BROILERS
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Solving resource availability cost problem in project scheduling by pseudo particle swarm optimization 被引量:4
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作者 Jianjun Qi Bo Guo +1 位作者 Hongtao Lei Tao Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第1期69-76,共8页
This paper considers a project scheduling problem with the objective of minimizing resource availability costs appealed to finish al activities before the deadline. There are finish-start type precedence relations amo... This paper considers a project scheduling problem with the objective of minimizing resource availability costs appealed to finish al activities before the deadline. There are finish-start type precedence relations among the activities which require some kinds of renewable resources. We predigest the process of sol-ving the resource availability cost problem (RACP) by using start time of each activity to code the schedule. Then, a novel heuris-tic algorithm is proposed to make the process of looking for the best solution efficiently. And then pseudo particle swarm optimiza-tion (PPSO) combined with PSO and path relinking procedure is presented to solve the RACP. Final y, comparative computational experiments are designed and the computational results show that the proposed method is very effective to solve RACP. 展开更多
关键词 project scheduling resource availability cost problem(RACP) HEURISTICS particle swarm optimization (PSO) path relin-king.
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Reliability and Availability Models of Belt Drive Systems Considering Failure Dependence 被引量:1
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作者 Peng Gao Liyang Xie Jun Pan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第2期133-144,共12页
Conventional reliability models of belt drive systems in the failure mode of fatigue are mainly based on the static stress strength interference model and its extended models, which cannot consider dynamic factors in ... Conventional reliability models of belt drive systems in the failure mode of fatigue are mainly based on the static stress strength interference model and its extended models, which cannot consider dynamic factors in the operational duration and be used for further availability analysis. In this paper, time-dependent reliability models, failure rate models and availability models of belt drive systems are developed based on the system dynamic equations with the dynamic stress and the material property degradation taken into account. In the proposed models, dynamic failure dependence and imperfect maintenance are taken into consideration. Furthermore, the issue of time scale inconsistency between system failure rate and system availability is proposed and addressed in the proposed system availability models. Besides, Monte Carlo simulations are carried out to validate the established models. The results from the proposed models and those from the Monte Carlo simulations show a consistency. Furthermore, the case studies show that the failure dependence, imperfect maintenance and the time scale inconsistency have significant influences on system availability. The independence assumption about the belt drive systems results in underestimations of both reliability and availability. Moreover, the neglect of the time scale inconsistency causes the underestimate of the system availability. Meanwhile, these influences show obvious time-dependent characteristics. 展开更多
关键词 availability RELIABILITY BELT DRIVE Failure DEPENDENCE Time scale INCONSISTENCY
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Failure Impact,Availability and Cost Analysis of PONs Based on a Network Geometric Model 被引量:1
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作者 FERNANDEZ Alvaro STOL Norvald 《光子学报》 EI CAS CSCD 北大核心 2014年第S1期18-24,共7页
Passive Optical Networks(PONs)are considered as the preferred solution for broadband fibre-based access networks.This is because PONs present low cost deployment,low energy consumption and also meet high bandwidth dem... Passive Optical Networks(PONs)are considered as the preferred solution for broadband fibre-based access networks.This is because PONs present low cost deployment,low energy consumption and also meet high bandwidth demands from end users.In addition,end users expect a high availability for access networks,while operators are more concerned about reducing the failure impact(number of clients affected by failures).Moreover,operators are also interested in reducing the cost of the access network.This paper provides a deep insight into the consequences that the physical topology and design decisions cause on the availability,the failure impact and the cost of a PON.In order to do that,the physical layout of the PON deployment area is approximated by a network geometric model.A PON deployed according to the geometric model is then assessed in terms of failure impact,availability and cost.This way,the effects of different design decisions and the physical layout on these three parameters are evaluated.In addition,the tradeoffs between availability,failure impact and cost caused by planning decisions and the physical topology are identified and pinpointed. 展开更多
关键词 availability FAILURE IMPACT CAPITAL Expenditures Passive Optical Networks NETWORK geometric model
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Seasonal Variation of Moisture Availability at Water-wind Erosion Crisscross Region in Northern Loess Plateau China 被引量:1
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作者 Tan Lu Wang Zhong-bo +1 位作者 Huang Jin-bai Yasuda Hiroshi 《Journal of Northeast Agricultural University(English Edition)》 CAS 2013年第4期72-77,共6页
The objectives of the current study were to estimate evapotranspiration(ET) over the grassland and assess seasonal variation of moisture availability at the wind-water erosion crisscross region in the northern Loess... The objectives of the current study were to estimate evapotranspiration(ET) over the grassland and assess seasonal variation of moisture availability at the wind-water erosion crisscross region in the northern Loess Plateau of China. The Liudaogou Catchment which has the representative climatic and hydrological characteristics of the wind-water erosion crisscross region was chosen as the study location. The reference crop evapotranspiration(ET 0) was estimated by Penmen method, which was recommended by FAO56 and the evapotranspiration over the grassland(ET) was estimated by Penmen-Monteith equation using the observed meteorological data with time unit of 1 h. The soil moisture availability factor was defined by m a =ET/ET 0. The calculated results for 2006 indicated that the total ET 0 was slightly more than the total yearly precipitation and ET accounted for 37 % of that, ET increased distinctly after the intensive rainfall event in the rainy season. Most of the m a was less than 0.4 and its annual mean was 0.34. It was expected that the results provided a basis for studies on dynamic functional analysis of soil moisture, relationship between soil water and crop growth at the wind-water erosion crisscross region in the northern Loess Plateau. 展开更多
关键词 Loess Plateau Liudaogou Catchment ET ET0 moisture availability
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Allocation of Repairable and Replaceable Components for a System Availability Using Selective Maintenance with Probabilistic Maintenance Time Constraints 被引量:3
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作者 Irfan Ali Mohammed Faisal Khan +1 位作者 Yashpal Singh Raghav Abdul Bari 《American Journal of Operations Research》 2011年第3期147-154,共8页
In this paper, we obtain optimum allocation of replaceable and repairable components in a system design. When repair and replace time are considered as random in the constraints. We convert probabilistic constraint in... In this paper, we obtain optimum allocation of replaceable and repairable components in a system design. When repair and replace time are considered as random in the constraints. We convert probabilistic constraint into an equivalent deterministic constraint by using chance constrained programming. We have used the selective maintenance policy to determine how many components to be replaced & repaired within the limited maintenance time interval and cost. A Numerical example is presented to illustrate the computational procedure and problem is solved by using LINGO Software. 展开更多
关键词 SELECTIVE Maintenance availability Optimization and ALLOCATION Chance’s CONSTRAINTS
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Differences among Somatotype, Body Composition and Energy Availability in Mexican Pre-Competitive Female Gymnasts 被引量:1
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作者 Adriana Poblano-Alcalá Debbie Braun-Zawosnik 《Food and Nutrition Sciences》 2014年第6期533-540,共8页
Gymnastics is a discipline that has some factors that differentiate from other sports, such as: force, postural control on movement, extreme range of motion, and of the body expression. The objec- tive of the present ... Gymnastics is a discipline that has some factors that differentiate from other sports, such as: force, postural control on movement, extreme range of motion, and of the body expression. The objec- tive of the present paper was to compare: somatotype, body composition and energy availability in female gymnasts students in search for a better sport performance. We evaluated 24 healthy female children aged 7 - 12 years by means of a nutritional and anthropometric examinations, somatotype and body composition calculation, and energy availability measurement. We observed a low consumption of real calories intake, carbohydrates, and low amount of the real body weight mesurements among gymnatics students. Mesomorphic and ectomorfic somatotypes were the more frequent somatotypes found. Moreover, we saw significant differences in body composition and in energy availability among the differente somatotypes in student of gymnastics. Differences were located between endomorphic, mesomorphic, and ectomorphic somatotype groups in body composition while in energy availability were among mesomorphic-ectomorphic, and between endomorphic-ectomorphic groups. In conclusion, our data had important implications for per- formance of gymnastics in students and were discussed here. 展开更多
关键词 GYMNASTICS SOMATOTYPE Body Composition Energy availability
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Availability and Profit Optimization of Series-Parallel System with Linear Consecutive Cold Standby Units 被引量:1
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作者 Muhammad Sagir Aliyu Ibrahim Yusuf U. A. Ali 《Applied Mathematics》 2015年第2期332-344,共13页
In this paper, we study availability and profit optimization of a series-parallel system consisting of three subsystems A, B and C in which A and B are cold standby. Subsystem A consists of linear consecutive k-out-of... In this paper, we study availability and profit optimization of a series-parallel system consisting of three subsystems A, B and C in which A and B are cold standby. Subsystem A consists of linear consecutive k-out-of-n units while subsystems B and C consist of a single unit each. The system works if any of A or B and C work. The objective of this study is to maximize the steady-state availability and profit. To solve the optimization problem, different numbers of units for n = 2, 3, 4, 5 in subsystem A are considered. Explicit expressions for busy period of repairmen, steady-state availability and profit function are derived using linear first order differential equations. Several cases are analyzed graphically for n = 2, 3, 4, 5 to investigate the effects of various system parameters on availability and profit. The paper also presents graphical comparison for specific values of system parameters and finds that the optimal system configuration is when n = 5. 展开更多
关键词 availability PROFIT COLD STANDBY Optimization
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Applying the Moisture Availability Index (NTDI) over Vegetated Land in Central Asia: Mongolian Steppe 被引量:1
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作者 Abdelmoneim A. Mohamed Reiji Kimura 《Journal of Water Resource and Protection》 2014年第14期1335-1343,共9页
The intensity of recent droughts and the uncertainty of moisture variability in the context of increasing temperatures and decreasing precipitation have affected the Mongolian grassland. Mongolia typifies the steppe t... The intensity of recent droughts and the uncertainty of moisture variability in the context of increasing temperatures and decreasing precipitation have affected the Mongolian grassland. Mongolia typifies the steppe terrain and semiarid to arid continental climate that extends across much of Central Asia. In semi-arid areas like Mongolian steppe, vegetation type and distribution are directly relate to the amount of water that plants can extract from the soil. An index for assessment of moisture availability (ma: defined as the ratio of actual to reference evapotranspiration) was developed, namely NTDI [1] 08D0C9EA79F9BACE118C8200AA004BA90B02000000080000000E0000005F005200650066003400300031003800340037003500380031000000 . NTDI (Normalized Day-Night Surface Temperature Difference Index) is defined as the ratio of the difference between the maximum daytime surface temperature and the minimum nighttime surface temperature, to the difference between the maximum and minimum surface temperatures estimated from meteorological data by applying energy balance equations. A verification study conducted at Liudaogou River Basin of the Loess Plateau, China, indicated the capability of NTDI to estimate ma accurately, (R2=0.97,p<0.001) [1] 08D0C9EA79F9BACE118C8200AA004BA90B02000000080000000E0000005F005200650066003400300031003800340037003500380031000000 . In Bayan Unjuul, Mongolia, application of NTDI during the growing season showed a significant inverse exponential correlation with ma (R2=0.86,p<0.001). This result indicates that the NTDI is potent to be used as a surrogate of moisture availability in steppe terrain of Central Asia. 展开更多
关键词 DROUGHT MONGOLIAN STEPPE Central ASIA NTDI MOISTURE availability (ma)
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