Cloud Based Software Computing as a Service in Hybrid Evolution Algorithm with Feedback Assistance

This paper develops cloud based software computing as a service (SCaaS) in the hybrid evolution algorithm with feedback assistance to solve the data optimal NP-complete problems such as travel salesman problems and job shop scheduling problems. Suitable steps, methods, or procedures of the genetic algorithm can be adopted from various evolution procedures or methods of the genetic algorithms based on the fitness evaluation results and survival ratio of different crossover methods in the current generation. The proposed system can dynamically emphasize the corresponding methods or procedures for the better performance in optimal solution searching. In addition, according to the proposed XML format, system users can upload only the coding of chromosomes without implementing the genetic algorithm program. Furthermore, by using the feedback assistance, the convergence time of the optimal solution can be enhanced.     

Evaluation of hydrogen producing cultures using pretreated food waste

In order to enhance bio-hydrogen production from food waste, pretreatment methods are widely used. The influence of the initial pH and autoclaving were investigated in batch experiments. Fermentative studies showed that pure cultures like Clostridium beijerinckii could directly utilize raw food waste to produce hydrogen, while other cultures (Clostridium butyricum and Clostridium pasteurianum) could produce hydrogen only after pH adjustment. In this case, the optimal starting pH of the culture was found to be 7. Autoclaving could further enhance hydrogen yields due to increased hydrolysis of food waste. The maximum hydrogen yield was achieved by C. butyricum (38.9 mL-H₂/g-VS_added) after autoclaving food waste with pH adjustment at 7. In addition, the ratio acetic to butyric acid was decreased by autoclaving pretreatment, because butyrate metabolic pathway was favored in the fermentation process. However, suitable pH for bacteria growth and the low ammonia production could be achieved from autoclaving food waste.     

Enhanced Strength and Corrosion Resistance of Mg–2Zn–0.6Zr Alloy with Extrusion

The microstructure, mechanical properties and corrosion behavior of Mg–2 Zn–0.6 Zr alloy under the as-cast and asextruded conditions were investigated. Microstructure analysis indicated the remarkable grain refinement by extrusion, as well as notable reductions in volume fraction and size of precipitate phases. As compared with the as-cast alloy, the asextruded alloy exhibited better mechanical performance, especially in yield strength which was promoted from 51 to 194 MPa. Refined grains, dispersive precipitate phases and texture were thought to be the main factors affecting the improved performance in strength. The electrochemical measurement and immersion test revealed the corrosion rate of Mg–2 Zn–0.6 Zr alloy by extrusion decreased from 1.68 to 0.32 mm/year. The reasons for the enhanced corrosion resistance were mainly attributed to the decreased volume fraction and Volta potential of the precipitate phases, the refinement of the grain size, as well as the formation of more protective corrosion film.     

食品中金黄色葡萄球菌和沙门氏菌检出能力验证结果与分析

目的提升食品中金黄色葡萄球菌和沙门氏菌的检测能力,增强实验室竞争力。方法依据能力验证作业指导书、国家标准GB 4789.10-2010《食品安全国家标准食品微生物学检验金黄色葡萄球菌检验》和GB 4789.4-2010《食品安全国家标准食品微生物学检验沙门氏菌检验》的要求,分别对1~#~5~#金黄色葡萄球菌待检样品和6~#~10~#沙门氏菌待检样品进行增菌、分离和生化反应鉴定。结果 10个待测样品中,2~#、4~#检出金黄色葡萄球菌,6~#、7~#检出沙门氏菌,10个样品均取得满意的结果。结论通过参加能力验证工作,可以较好地提高实验室的检测能力。     

食品中磷脂提取及分析方法的研究进展

磷脂是细胞的重要组成成分,对生物体的生长和发育具有重要作用,也是天然的乳化剂、表面活性剂,在食品、医药、化妆品等领域具有广泛的应用。由于每种磷脂分子可以结合不同的脂肪酸,导致磷脂种类繁多且结构复杂,对磷脂的分析比较困难。本文从磷脂的种类及应用、提取纯化、检测方法等方面,对食品中磷脂的研究进展进行概述,比较不同研究方法的优缺点,以期为不同食品中磷脂的深入研究和开发提供参考。     

H2 and CH4 oxidation on Gd0.2Ce0.8O1.9 infiltrated SrMoO3–yttria-stabilized zirconia anode for solid oxide fuel cells

Strontium molybdate (SrMoO₃) as an electronic conductor was incorporated with yttria-stabilized zirconia (YSZ) to form an anode scaffold for solid oxide fuel cells. Gd_0.2Ce_0.8O_1.9 (GDC) nanoparticles were introduced by wet impregnation to complete the Ni-free GDC infiltrated SrMoO₃–YSZ anode fabrication. The effects of SrMoO₃ on the electrode conductivity and GDC infiltration on the catalytic activity were examined. A pronounced performance improvement was observed both on wet H₂ and CH₄ oxidation for the 56 wt.% GDC infiltrated SrMoO₃–YSZ. In particular, the polarization resistance decreased from 8 Ω cm² to 0.5 Ω cm² under wet H₂ (3% H₂O) at 800 °C with the introduction of GDC. Under wet CH₄ at 900 °C, a maximum power density of 160 mW cm⁻² was obtained and no carbon deposition was observed on the anode. It was found that the addition of H₂O in the anode caused an increase of electrode ohmic resistance and a decrease of open circuit voltage. Redox cycling stability was investigated and only a slight drop in cell performance was observed after 5 cycles. These results suggest that GDC infiltrated SrMoO₃–YSZ is a promising anode material for solid oxide fuel cells.     

基于多Agent系统的数字家庭模型研究

基于Agent的仿真是研究分布式复杂系统的重要内容,数字家庭是分布式应用的一个方面,IBMAglet是一个实现基于Agent仿真模型的软件工具。文中详细阐述了使用IBMAglet仿真平台实现数字家庭仿真模型的一般方法,探索了在IBMAglet仿真模型中的Agent和Agent交互的方法与过程。为该领域的研究者在模型实现这一问题上提供了一定的参考。     

Construction and performance analysis of 2-D codes for M-ary OFFH?CDMA systems

A new family of two-dimensional (2-D) codes constructed by combining frequency-hop and time-spreading codes is presented. The proposed codes are designed to overcome the limitation imposed on the maximum permissible number of simultaneous users in optical code-division multiple-access (OCDMA) systems. To increase the data transmission rate, the 2-D codes employ a M-ary signalling scheme. The proposed family of codes has the favourable characteristics of a zero autocorrelation constraint and a cross-correlation constraint of one. The performance of the 2-D code is analysed in terms of the bit error rate (BER) and is compared with that of a conventional OCDMA system using optical orthogonal code (OOC). The numerical and simulation results reveal that the proposed system outperforms conventional OCDMA systems both in terms of the BER and the data transmission rate. In addition, the system capacity is sufficient to ensure reliable communication (BERles10^-9) in local area networks     

Insight into Conformational Change for 14-3-3σ Protein by Molecular Dynamics Simulation

14-3-3σ is a member of a highly conserved family of 14-3-3 proteins that has a double-edged sword role in human cancers. Former reports have indicated that the 14-3-3 protein may be in an open or closed state. In this work, we found that the apo-14-3-3σ is in an open state compared with the phosphopeptide bound 14-3-3σ complex which is in a more closed state based on our 80 ns molecular dynamics (MD) simulations. The interaction between the two monomers of 14-3-3σ in the open state is the same as that in the closed state. In both open and closed states, helices A to D, which are involved in dimerization, are stable. However, large differences are found in helices E and F. The hydrophobic contacts and hydrogen bonds between helices E and G in apo-14-3-3σ are different from those in the bound 14-3-3σ complex. The restrained and the mutated (Arg56 or Arg129 to alanine) MD simulations indicate that the conformation of four residues (Lys49, Arg56, Arg129 and Tyr130) may play an important role to keep the 14-3-3σ protein in an open or closed state. These results would be useful to evaluate the 14-3-3σ protein structure-function relationship.     

Huge Page Friendly Virtualized Memory Management

With the rapid increase of memory consumption by applications running on cloud data centers,we need more efficient memory management in a virtualized environment.Exploiting huge pages becomes more critical for a virtual machine's performance when it runs large working set size programs.Programs with large working set sizes are more sensitive to memory allocation,which requires us to quickly adjust the virtual machine's memory to accommodate memory phase changes.It would be much more efficient if we could adjust virtual machines'memory at the granularity of huge pages.However,existing virtual machine memory reallocation techniques,such as ballooning,do not support huge pages.In addition,in order to drive effective memory reallocation,we need to predict the actual memory demand of a virtual machine.We find that traditional memory demand estimation methods designed for regular pages cannot be simply ported to a system adopting huge pages.How to adjust the memory of virtual machines timely and effectively according to the periodic change of memory demand is another challenge we face.This paper proposes a dynamic huge page based memory balancing system(HPMBS)for efficient memory management in a virtualized environment.We first rebuild the ballooning mechanism in order to dispatch memory in the granularity of huge pages.We then design and implement a huge page working set size estimation mechanism which can accurately estimate a virtual machine's memory demand in huge pages environments.Combining these two mechanisms,we finally use an algorithm based on dynamic programming to achieve dynamic memory balancing.Experiments show that our system saves memory and improves overall system performance with low overhead.