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991.
云计算环境资源监控系统研究   总被引:1,自引:0,他引:1  
为保障云计算平台的可靠性,基于Ganglia,采用Eucalyptus开源云平台,提出了云计算平台资源监控系统架构.从总体结构、监控信息处理流程等多个方面对监控系统进行了详细阐述,提出了动态更换虚拟机簇头的算法,并对算法与原型系统进行了验证和性能评测.分析与评测结果表明,所提系统能够适用于云计算环境资源信息的实时监测与预警,具备系统开销较低,用户接口友好的特点,能准确反映系统、虚拟机的负载信息,有助于云计算系统服务可靠性的提升.簇头动态更换算法能及时发现失效的簇头并更换为更健壮的虚拟机,保证了监测系统的正常运行.  相似文献   
992.
蚁群算法是最近十余年刚刚兴起的一种高效的仿生优化算法,算法采用分布式并行计算和正反馈自我催化机制,具有易与和其他算法结合等特点.将其应用于断层追踪能够客观、全面的诠释断层的空间展布情况,有效的提高断层解释精度.以喇南中东一区萨二油层组为例,应用基于蚁群算法下断层追踪方法准确落实目的层段断层展布规律,能够很好地解决原认识在开发过程中所遇到的矛盾,对于深入油层开发、完善注采系统、挖潜剩余油具有一定的指导意义.  相似文献   
993.
以CNKI收录的2007-2012年间5212篇云计算文献为研究对象,采用文献计量、社会网络分析法,从文献的年代、来源期刊及基金资助分布,作者及其合作、研究机构及其合作,研究热点及其演进等方面可视化分析了国内云计算研究进展.  相似文献   
994.
库存合理分类对企业的库存管理非常重要.在现有ABC库存分类指标体系的基础之上,指出需求波动对库存分类的重要性,设计了考虑需求波动系数的.ABC库存分类多指标体系;进一步,分析了指标的差异性对库存分类的影响,提出了基于信息熵的多指标ABC库存分类方法.与已有文献对比分析表明,所设计的多指标分类体系综合考虑了库存物资的不同属性;对某家电企业的案例分析可以看出,所提出的.ABC库存分类的多指标体系及其信息熵方法有助于企业制定合理的库存决策,可有效提高企业的管理绩效.  相似文献   
995.
Abstract

Microemulsification and blending of commercial diesel is under constant research for possible fuel application. Microemulsions (ME) were prepared using diesel (D), kerosene (K), diesel and kerosene mixtures at various proportions (D?+?K) (oil phase: O), Triton X-100 surfactant (S), n-butanol, isobutanol (i-butanol), n-pentanol and n-octanol cosurfactants (C), and aqueous phase (W) containing water or brine for the study. Electrical conductance studies and temperature-induced separation of phase have been adopted for recognizing the o/w, w/o and bicontinuous zones. Dye probing has been done to explain the mass transfer among these phases. Percent of solubilization of oil in water has been enumerated in some of the ME. The possible fuel applications of the microemulsions are predicted from their density and flame brightness.  相似文献   
996.
A benchmark study on all possible density functional theory (DFT) methods in Gaussian09 is done to locate functionals that agree well with CCSD/aug‐cc‐pVTZ geometry and Ave‐CCSD(T)/(Q‐T) interaction energy (Eint) for small non‐covalently interacting molecular dimers in “dispersion‐dominated” (class 1), “dipole‐induced dipole” (class 2), and “dipole‐dipole” (class 3) classes. A DFT method is recommended acceptable if the geometry showed close agreement to CCSD result (RMSD < 0.045) and Eint was within 80–120% accuracy. Among 382 tested functionals, 1–46% gave good geometry, 13–44% gave good Eint, while 1–33% satisfied geometry and energy criteria. Further screening to locate the best performing functionals for all the three classes was made by counting the acceptable values of energy and geometry given by each functionals. The meta‐generalized gradient approximation (GGA) functional M06L was the best performer with total 14 hits; seven acceptable energies and seven acceptable geometries. This was the only functional “recommended” for at least two dimers in each class. The functionals M05, B2PLYPD, B971, mPW2PLYPD, PBEB95, and CAM‐B3LYP gave 11 hits while PBEhB95, PW91B95, Wb97x, BRxVP86, BRxP86, HSE2PBE, HSEh1PBE, PBE1PBE, PBEh1PBE, and PW91TPSS gave 10 hits. Among these, M05, B971, mPW2PLYPD, Wb97x, and PW91TPSS were among the “recommended” list of at least one dimer from each class. Long‐range correction (LC) of Hirao and coworkers to exchange‐correlation functionals showed massive improvement in geometry and Eint. The best performing LC‐functionals were LC‐G96KCIS and LC‐PKZBPKZB. Our results predict that M06L is the most trustworthy DFT method in Gaussian09 to study small non‐covalently interacting systems. © 2013 Wiley Periodicals, Inc.  相似文献   
997.
The present study investigates the effect of different additives on the cloud point (CP) of nonionic surfactants Triton X-100 (TX-100) and Triton X-114 (TX-114) in aqueous solutions. The thermodynamic parameters of these mixtures were calculated at different additive concentrations. The cloud point of nonionic surfactants TX-100 and TX-114 decreased with the increment of electrolyte concentrations and increased with alcohol concentrations. The standard Gibbs free energy was found to be positive for both the surfactants, whereas the enthalpy and the entropy of the clouding phenomenon were found to be positive with alcohols and negative with electrolytes. The overall clouding process was endothermic for alcohols and exothermic for electrolytes.  相似文献   
998.
An inclusion complex formation using β‐cyclodextrin (β‐CD) as the host molecule and deltamethrin as guest molecule was a first step towards improvement in conventional insecticide formulations. β‐CD‐deltamethrin inclusion complex formation in the absence and presence of the nonionic myrisitic acid monoethanolamide (C14MEA)/anionic α‐olefin sulfonate C12‐C14 (AOS) mixed surfactant system was comparatively studied. The co‐evaporation method was used for complex formation, which was subsequently characterized by analytical methods such as FTIR and XRD techniques. Important physical properties such as solubility, dispersion stability, and wettability were also studied.  相似文献   
999.
Surfactants/polymers are used extensively in drug delivery as drug carriers. We herein report the effect of surfactants and polymers on the cloud point (CP) of amphiphilic drug chlorpromazine hydrochloride. At fixed drug concentration (50 mM) and pH (6.7) these additives affect the CP in accordance to their nature and structure: anionic surfactants show an increase followed by a decrease, whereas cationic (conventional as well as gemini) and nonionic surfactants show continous increase. The behavior with polymers is dictated by the number of units present in a particular polymer. Increase in drug concentration and pH, in presence of fixed amounts of CTAB, increases and decreases the CP, respectively. Variation of CP with pH at various fixed gemini concentrations shows that gemini surfactants are better candidates for drug delivery.  相似文献   
1000.
In this study, a novel method to determine the cloud point temperature variation in aqueous solutions of thermoresponsive homo- and copolymers was developed. Poly(N-vinylcaprolactam) (PVCL) and triblock copolymers of poly(t-butyl acrylate-co-acrylic acid)-b-poly(N-vinylcaprolactam)-b-(t-butyl acrylate-co-acrylic acid) (P[(tBA-co-AA)-b-PVCL-b-P(tBA-co-AA)] were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization and used as models. The incorporation of AA units (hydrophilic segments) into the polymeric chain of PVCL influenced the phase transition, increasing the cloud point temperature of the final copolymer. The cloud point temperatures of the PVCL and the triblock copolymer P(tBA-co-AA)-b-PVCL-b-P(tBA-co-AA) were determined by measuring the transmittance of aqueous solutions of the polymers in a Turbiscan Lab instrument in the range of 29 to 40 C. This is the first study in which Turbiscan Lab is used to determine the cloud point temperature.  相似文献   
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