A threshold-based dynamic data replication strategy

Data replication is the creation and maintenance of multiple copies of the same data. Replication is used in Data Grid to enhance data availability and fault tolerance. One of the main objectives of replication strategies is reducing response time and bandwidth consumption. In this paper, a dynamic replication strategy that is based on Fast Spread but superior to it in terms of total response time and total bandwidth consumption is proposed. This is achieved by storing only the important replicas on the storage of the node. The main idea of this strategy is using a threshold to determine if the requested replica needs to be copied to the node. The simulation results show that the proposed strategy achieved better performance compared with Fast Spread with Least Recently Used (LRU), and Fast Spread with Least Frequently Used (LFU).     

Consumption universes based supermarket layout through association rule mining and multidimensional scaling

The success of retail business is influenced by its fast response and its ability in understanding consumers’ behaviors. Analysis of transaction data is the key for taking advantage of these new opportunities, which enables supermarkets to understand and predict customer behavior, has become a crucial technique for effective decision-making and strategy formation. We propose a methodological framework for the use of the knowledge discovery process and its visualization to improve store layout. This study examines the layout strategy in relation to supermarket retail stores and assists managers in developing better layout for supermarkets. We use the buying association measure to create a category correlation matrix and we apply the multidimensional scale technique to display the set of products in the store space. This is a new approach to supermarket layout from industrial categories to consumption universes that is consumer-oriented store layout approach through a data mining approach. This framework is useful for both academia and retail industry. For industry professionals, it may be used to guide development of successful layout. Retailers can utilize the proposed model to dynamically improve their in-store conversion rate. As the empirical study, a practical application proceeded for Migros Turk, a leading Turkish retailing company.     

Adaptive Neuro-Fuzzy Inference System for diagnosis risk in dengue patients

Dengue disease is considered as one of the life threatening disease that has no vaccine to reduce its case fatality. In clinical practice the case fatality of dengue disease can be reduced to 1% if the dengue patients are hospitalized and prompt intravenous fluid therapy is administrated. Yet, it has been a great challenge to the physicians to decide whether to hospitalize the dengue patients or not due to the overlapping of the medical diagnosis criteria of the disease. Beside that physicians cannot decide to admit all patients because this will have major impact on health care cost saving due to the huge incident of dengue disease in the country. Even if the physicians managed to identify the critical cases to be hospitalized, most of the tools that have been used for monitoring those patients are invasive. Therefore, this study was conducted to develop a non-invasive accurate diagnostic system that can assist the physicians to diagnose the risk in dengue patients and therefore attain the correct decision. Bioelectrical Impedance Analysis measurements, Symptoms and Signs presented with dengue patients were incorporated with Adaptive Neuro-Fuzzy Inference System (ANFIS) to construct two diagnostic models. The first model was developed by systematically optimizing the initial ANFIS model parameters while the second model was developed by employing the subtractive clustering algorithm to optimize the initial ANFIS model parameters. The results showed that the ANFIS model based on subtractive clustering technique has superior performance compared with the other model. Overall diagnostic accuracy of the proposed system is 86.13% with 87.5% sensitivity and 86.7% specificity.     

A New Grid Scheduler with Failure Recovery and Rescheduling Mechanisms: Discussion and Analysis

Computational Grids (CGs) have become an appealing research area. They suggest a suitable environment for developing large scale parallel applications. CGs integrate a huge mount of distributed heterogeneous resources for constituting a powerful virtual supercomputer. Scheduling is the most important issue for enhancing the performance of CGs. Various strategies have been introduced, including static and dynamic behaviors. The former maps tasks to resources at submission time, while the latter operates at run time. While static scheduling is unsuitable for the dynamic Grid environment, scheduling in CGs is still more complex than the proposed dynamic solutions. This paper introduces a decentralized Adaptive Grid Scheduler (AGS) based on a novel rescheduling mechanism. AGS has several salient properties as it is; hybrid, adaptive, decentralized, and efficient. Also, AGS is a robust mechanism as it has the ability to; (i) detect resource failures, (ii) continue its functionality in spite of the failure existence, then (iii) recover back. Moreover, it integrates both static and dynamic scheduling behaviors. An initial static scheduling map is proposed for an input Direct Acyclic Graph (DAG). However, DAG tasks may be rescheduled if the performance of the allocated resources changes in away that may affect the tasks’ response time. AGS overcomes drawbacks of traditional schedulers by utilizing the mobile agent unique features to enhance the resource discovery and monitoring processes. Experimental results have shown that AGS outperforms traditional Grid schedulers as it introduces a better scheduling efficiency.     

Synthesis of novel functionalized methacrylate copolymers and their copolymerization kinetics,thermal stability,and biocidal properties

In the first step of this study, 2-[(methoxy-1,3-benzothiazole-2-yl)amino]-2-oxoethyl methacrylate (MBAOM) monomer was synthesized and characterized. Then, a series copolymers were obtained by free-radical copolymerization method of MBAOM and glycidyl methacrylate, which is a commercial monomer at 65°C in 1,4-dioxane solvent. Structural characterizations of synthesized monomer and copolymers were carried out using Fourier transform infrared spectrophotometer and nuclear magnetic resonance spectroscopy (¹H and ¹³C-NMR) instruments. The composition of the copolymers was estimated by elemental analysis. The thermal behaviors of all the polymers have been investigated using the differential scanning calorimetry and the thermogravimetric analysis. A kinetic study of the thermal decomposition of copolymers was investigated using thermogravimetric analyzer with non-isothermal methods selected for analyzing solid-state kinetics data. The activation energy (E_a) values were calculated via Kissinger and Ozawa models in a period of α = 0.10–0.80. Photostability of the copolymers was investigated. Also, the biological activity of the copolymers against different bacterial and fungal species has been investigated.     

Minimizing cycle time and group scheduling, using Petri nets a study of heuristic methods

The objective of this paper is a study of minimizing the maximum completion time min F _max, or cycle time of the last job of a given family of jobs using flow shop heuristic scheduling techniques. Three methods are presented: minimize idle time (MIT); Campbell, Dudek and Smith (CDS); and Palmer. An example problem with ten jobs and five machines is used to compare results of these methods. A deterministic t-timed colored Petri net model has been developed for scheduling problem. An execution of the deterministic timed Petri net allows to compute performance measures by applying graph traversing algorithms starting from initial global state and going into a desirable final state(s) of the production system. The objective of the job scheduling policy is minimizing the cycle time of the last job scheduled in the pipeline of a given family of jobs. Three heuristic scheduling methods have been implemented. First, a sub-optimal sequence of jobs to be scheduled is generated. Second, a Petri net-based simulator with graphical user interface to monitor execution of the sequence of tasks on machines is dynamically designed. A deterministic t-timed colored Petri net model has been developed and implemented for flexible manufacturing systems (FMS). An execution of the deterministic timed Petri net into a reachability graph allows to compute performance measures by applying graph traversing algorithms starting from initial global state to a desirable final state(s) of the production system.     

Preparation, characterization and crystal structure of 4,4′-bipyridinium nitrate trinitratodioxo-uranium(VI) and 4,4′-dipyridinium diaqua hexanitrato-thorate(IV)

The compounds 4,4′-bipyridinium nitrate trinitratodioxo-uranium(VI) [UO₂(NO₃)₃][4,4′-bipyH]·HNO₃ (1) and 4,4′-dipyridinium diaqua hexanitrato-thorate(IV) [Th(NO₃)₆][4,4′-bipyH₂]·2H₂O (2) were prepared and characterized. Their crystal structures have been determined using X-ray diffraction techniques. Both complexes crystallize in the monoclinic system with space groups P2₁/c for 1 and C2/c for 2. The geometry of the anion in 1 is a distorted hexagonal bipyrimidial coordination, while that in 2 is a distorted icosahedron. The cation in 1 is formed from hydrogen-bonded monoprotonated bipyridyl with a neutral nitrate molecule, whereas the cation in 2 is formed from hydrogen-bonded diprotonated bipyridyl with a water molecule. The cations in both complexes are connected with the anions through hydrogen bonds via the nitrate molecule in 1 and the water molecule in 2.     

ENERGY AND GDP

Understanding of the role of energy use at the national level requires the understanding of the relationship of energy use to economic activity and social well-being. Gross domestic product (GDP) measures the value of goods and services produced in a country in one year. There is a close relationship between energy supply, energy consumption, and GDP, which indicates the economic development of a country. The living standard of a country is often measured by the per capita GDP. This article presents the evaluations and future projections of energy and energy resources of the Organization for Economic Cooperation and Development (OECD). The total primary energy supply, total final energy consumption, and energy intensities for supply and consumption are analysed. The energy data for all OECD countries are presented and analyses of the differences in energy and GDP ratios are conducted at an aggregate level by examining differences in the factors that affect the energy intensities. To provide accurate projections for the future, new correlations are developed between average GDP, total primary energy supply, total final consumption, total per capita primary energy supply, total per capita final consumption and total OECD population. © 1997 by John Wiley & Sons, Ltd.     

Electrical studies on PVA-PE copolymer

The electrical transport properties including electrical conductivity (σ), dielectrical constant (ϵ′), thermally stimulated depolarization current (TSDC), and pyroelectric coefficient (P) of a poly(vinyl alcohol)-polyethylene (PVA-PE) copolymer were studied in the temperature range 296–433 K. Two stages of behavior have been observed with activation energies 1.49 and 0.05 eV. Discussion of conduction mechanism was carried out in terms of relevant theories. The existence of a relaxation peak in ϵ′ versus T relation has been analyzed taking into consideration space charge effects and dipole orientation phenomena. The TSDC spectra showed two peaks with differing intensity and position independent of field intensity. Pyroelectric current data provide further support to space charge effects. © 1997 John Wiley & Sons, Inc.     

Synthese und Eigenschaften neuartiger Alkalimetall-Alkoxo- und -Aroxocobaltate(II)

Synthesis and Properties of Novel Alkali Metal Alkoxo- and Aroxocobaltates(II) . By reaction of CoBr₂ or CoBr₂ · 2THF with 4–5 moles of MOR in THF, M  Li, Na, K, R = iso-propyl (iPr), phenyl (Ph), 2-naphthyl (2-Naph), the following novel alkali metal alkoxo- and aroxocobaltates(II) have been prepared. Li₂Co(OiPr)₄ · LiBr · 3THF ( 1 ), Na₂Co(OiPr)₄ · THF ( 2 ), KCo(OiPr)₃ · THF ( 3 ), Li₂Co(OPh)₄ · 4THF ( 4 ), Na₂Co(OPh)₄ · 5THF ( 5 ), K₂Co(OPh)₄·0,75THF ( 6 ), Li₂Co(O-2-Naph)₄ · 4THF ( 7 ), Na₂Co(O-2-Naph)₄ · 5THF ( 8 ), K₂Co(O-2-Naph)₄ · 2THF ( 9 ), and K₃Co(O-2-Naph)₅ · 2THF ( 10 ). The blue and violet, crystalline and very air-sensitive (i.e. protolytically sensitive) compounds, some with good solubilities in organic solvents, eliminate THF in vacuo at temperatures between 50 and 100°C to yield the corresponding THF-free compounds ( 1a ) to ( 10a ). Electronic spectra (VIS/NIR) and the results of magnetic measurements at 293 K point to preferred (but not exclusive) tetrahedral coordination of cobalt(II).