一种基于非对称结构的虚拟存储网络的实现

全球范围内数据量的飞速增长，对存储系统提出了更高的要求，网络存储越来越受到人们的关注。目前流行的网络存储技术是NAS和SAN。NAS和SAN各有自己的体系架构、互联协议、文件组织和管理方式等。而将这两种技术融合到一个统一的结构框架下已经成为目前人们关注的热点问题。本文利用存储虚拟化技术，采用非对称结构模型，实现了一种融合NAS和SAN的虚拟存储网络。     

数据存储结构与检索效率关系的研究--关于DNA数据存储结构与比对效率

数据库系统区别于其他系统的重要方面之一是DBMS具有有效地处理非常大量数据的能力,但随着数据量的增长,数据的检索速度日益捉襟见肘,如何提高数据的检索效率逐渐受到重视,特别是在一些特殊领域对数据的实时性要求较高的情况下,更需要快速的数据检索.本文正是基于此考虑,以DNA的数据存储为例,针对DNA数据的特点及实际比对的需要,通过具体的数据库实现技术,分析了存储结构对数据库访问速度的影响,在此基础上通过对几个具体方案的实际测试,给出了一个相对较优的数据库存储结构解决方案.     

Conception of the optical sensors based on transient processes in MIS structures

New silicon-based optical sensors with metal–insulator–semiconductor structure (MIS) have been developed in this work. The physical properties of these sensors are described with a simple MIS capacitor model. Two-level voltage bias provides a transient between two quasi-equilibrium inversion modes. This transient is applied for storage and readout of the input optical signal for a quantitative measurement of a weak radiation. Proposed simple readout procedure provides reading the integrated information with a significant amplification. The amplification (or the current transformation coefficient) is determined by the ratio of integration and readout times and in this investigation the amplification exceeds the value of 10³. A simple theoretical model is applied to describe the sensor properties at illumination. Numerical calculation under the experimental conditions confirms a validity of the physical model and arguments used at the discussion of the experimental results.     

基于XML的复杂信息结构系统的研究与实现

针对复杂信息结构具有信息种类多、结构层次关系复杂、数据信息多维化、查询操作维护困难等特点 ,提出以XML作为中间衔接技术组织和管理多维、异构信息数据 ,以关系数据库和XML文档作为存储多维、异构信息数据的存储方案 ,设计了存储复杂信息数据的XML形数据结构 ,实现复杂信息数据的管理维护 ,为复杂信息结构数据在Web上交互、共享和存储提供了一种实现方案。     

Improving reliability and performances in large scale distributed applications with erasure codes and replication

Replication of Data Blocks is one of the main technologies on which Storage Systems in Cloud Computing and Big Data Applications are based. With the heterogeneity of nodes, and an always-changing topology, keeping the reliability of the data contained in the common large-scale distributed file system is an important research challenge. Common approaches are based either on replication of data or erasure codes. The former stores each data block several times in different nodes of the considered infrastructures: the drawback is that this can lead to large overhead and non-optimal resources utilization. Erasure coding instead exploits Maximum Distance Separable codes that minimize the information required to restore blocks in case of node failure: this approach can lead to increased complexity and transfer time due to the fact that several blocks, coming from different sources, are required to reconstruct lost information. In this paper we study, by means of discrete event simulation, the performances that can be obtained by combining both techniques, with the goal of minimizing the overhead and increasing the reliability while keeping the performances. The analysis proves that a careful balance between the application of replication and erasure codes significantly improves reliability and performances avoiding large overheads with respect to the isolated use of replication and redundancy.     

Effect of particle morphology on viscoelastic and flexural properties of epoxy–alumina polymer nanocomposites

Nanocomposites were synthesised by dispersing two different types of alumina nanoparticles in epoxy matrix by ultrasonication. Alumina nanoparticles of two shapes, rod and spherical were selected to investigate the effect of particle morphology on viscoelastic and flexural properties of nanocomposites. Specific surface area of both the selected nanoparticles was kept in the similar range. Good dispersion of nanoparticles was observed through transmission electron microscopy. The addition of nanoparticles in epoxy had significant enhancement in the viscoelastic properties and moderate improvement in flexural properties of composites. Composites having alumina nanorods showed higher improvement both in storage modulus as well as in flexural properties in comparison to composites having spherical alumina nanoparticles. Efficacy of Mori-Tanaka method was explored in modelling storage modulus of nanocomposites. Assorted size of alumina nanorods based on particle size distribution was used to model composites with nanorods to see the effect of size assortment on storage modulus.     

Sensitization to Sitophilus granarius in selected suburban population of South Poland

Storage insects may cause occupational allergies in humans. The identification of the prevalence of IgE reactions were measured from protein fractions prepared from multiple life stage of granary weevil Sitophilus granarius [SG] is reported. Sera of 30 patients from a suburban population of Upper Silesia (South Poland) were tested for the presence of IgE antibodies to antigens from larvae, pupae and adults of both sexes of the beetle. To identify protein fractions containing potential allergens, proteins collected from four life stages of granary weevil were fractionated by SDS-PAGE and probed with anti-human, anti-IgE monoclonal antibodies. The proteins were fractionated by SDS PAGE and identified by Western blot. The patients’ antibodies against particular antigens were identified using anti-human anti-IgE monoclonal antibody. The conducted immunological analysis showed the existence of many protein fractions for each life stage of SG which give positive reactions with IgE antibodies. The largest number of allergenic potential fractions was shown in pupae (60 protein fractions) while the smallest amount was shown in larvae (44 protein fractions). Summarizing, the obtained results suggest the existence of many protein fractions with an allergenic potential multiple life stages of SG. This indicates that all developmental stages of SG may be a serious source of antigens and potential risk factors for the exposed persons.     

Triple bag hermetic technology for controlling a bruchid (Spermophagus sp.) (Coleoptera,Chrysomelidae) in stored Hibiscus sabdariffa grain

We assessed the performance of hermetic triple layer Purdue Improved Crop Storage (PICS) bags for protecting Hibiscus sabdariffa grain against storage insects. The major storage pest in the grain was a bruchid, Spermophagus sp.. When we stored infested H. sabdariffa grain for six months in the woven polypropylene bags typically used by farmers, the Spermophagus population increased 33-fold over that initially present. The mean number of emergence holes per 100 seeds increased from 3.3 holes to 35.4 holes during this time period, while grain held for the same length of time in PICS bags experienced no increase in the numbers of holes. Grain weight loss in the woven control bags was 8.6% while no weight loss was observed in the PICS bags. Seed germination rates of grain held in woven bags for six months dropped significantly while germination of grain held in PICS bags did not change from the initial value. PICS bags can be used to safely store Hibiscus grain after harvest to protect against a major insect pest.     

The role of decentralized generation and storage technologies in future energy systems planning for a rural agglomeration in Switzerland

This study presents a framework to quantitatively evaluate decentralized generation and storage technology (DGST) performance and policy impacts in a rural setting. The role of DGSTs in the future energy systems planning of a rural agglomeration in Switzerland is examined using a cost optimization modeling approach. Heat and electricity demand for major sectors are considered. Scenarios introduce DGSTs in a stepwise manner to measure incremental impacts on future capacity planning compared to a baseline scenario. Sub-scenarios also examine the impacts of carbon mitigation policies, and a sensitivity analysis is carried out for key energy carriers and conversion technologies. DGSTs enable a significant reduction in electricity grid usage for the community considered. Small hydro with a storage reservoir and photovoltaics enable the community to become largely self-sufficient with over 80% reductions in grid imports by 2050 compared to the baseline scenario. Storage enables maximum usage of the available hydro potential which also leads to network upgrade deferrals and a significant increase in photovoltaic installations. Investment decisions in small hydro are robust against cost variations, while heating technology investment decisions are sensitive to oil and grid electricity prices. Carbon pricing policies are found to be effective in mitigating local fossil fuel emissions.     

Application of metaheuristics-based clustering algorithm to item assignment in a synchronized zone order picking system

Warehousing management policy is a crucial issue in logistic management. It must be managed effectively and efficiently to reduce the production cost as well as the customer satisfaction. Synchronized zoning system is a warehousing management policy which aims to increase the warehouse utilization and customer satisfaction by reducing the customer waiting time. This policy divides a warehouse into several zones where each zone has its own picker who can work simultaneously. Herein, item assignment plays an important role since it influences the order processing performance. This study proposes an application of metaheuristic algorithms, namely particle swarm optimization (PSO) and genetic algorithm (GA), for item assignment in synchronized zoning system. The original PSO and GA algorithms are modified so that it is suitable for solving item assignment problem. The datasets with different sizes are used for method validation. Results obtained by PSO and GA are then compared with the result of an existing algorithm. The experimental results showed that PSO and GA can perform better than the existing algorithm. These results also show that PSO has better performance than GA, especially for bigger problems. It proves that item assignment policy obtained by PSO and GA has higher utilization rates than the existing algorithm.