Modeling evidential databases as possible worlds

This paper is about modeling a possible worlds' form of imperfect databases, where imperfection is handled with the evidence theory. The possible worlds' form is already developed for other types of imperfect databases such as probabilistic and possibilistic databases. Such a form is essential to prove that a compact form querying method is a strong representation system. For the same aim, we propose in this article an extended model of possible worlds's form treating the tuple‐level uncertainty in addition to the attribute‐level uncertainty.     

Multi-constraints self-adaptation for reconfigurable multimedia embedded systems

The application of multimedia in embedded systems (ES), such as Virtual reality and 3-D imaging, represents the current trend in ES development. Coupling multimedia with ES has raised new multimedia-related challenges that have been added to the common ES constraints. These challenges deal with the real-time, quality, performance and efficient processing requirements of multimedia applications. The integration of self-adaptation in ES development has been, for many years, a paramount solution to cope with these issues. Although there has been extensive research on the topic of ES self-adaptation, the related works still lack global approaches that better deal with multimedia-related constraints. Coordinating different adaptation mechanisms, monitoring multiple system constraints and supporting multi-application contexts are still underexplored. The aim of the present work is to fill in these gaps by providing a global adaptation approach that offers better adaptation decisions with fair resource sharing among competing multimedia applications. With the above challenges in mind, we propose a multi-constraints combined adaptation approach that targets multimedia ES. It addresses four critical system constraints: maximizing the overall system‘s Quality of Application (QoA) under the real-time constraint, the remaining system energy and the available network bandwidth. It coordinates the adaptation at both application and architecture levels. To test and validate the proposed technique, a videophone system is designed on a Xilinx FPGA development board. It executes two complex multimedia applications. The validation results show the aptitude of the proposed system to successfully reconfigure itself at run-time in response to its constraints.

     

VUV-UV photoluminescence,site occupancy and thermal stability of blue-emitting K2CaP2O7:Eu2+ UV-LED phosphor

Blue-emitting phosphors K₂Ca_1?xP₂O₇:xEu²⁺ (x?=?0.005; 0.010; 0.015) were prepared by a solid-state reaction. The luminescence properties of the phosphors were systematically investigated. VUV photoluminescence spectra of K₂Ca_1?xP₂O₇:xEu²⁺ exhibit that three distinct bands peaking at 439, 478 and 535 nm can be attributed to the overlap of Eu(1), Eu(2) and Eu(3) emission bands, which are ascribed to the 4f–5d transition of Eu²⁺. The critical quenching concentration of Eu²⁺ in K₂CaP₂O₇ phosphor is about 1 mol%, and the critical transfer distance was determined to be 32.23 Å. When the temperature turned up to 150 °C, the emission intensity of K₂Ca_0.99P₂O₇:0.01Eu²⁺ sample was 60% of the initial value at room temperature. The activation energy E_a was calculated to be 0.217 eV, which proved the good thermal stability of the phosphor. All the properties indicated that the K₂CaP₂O₇:Eu²⁺ is promising blue-emitting phosphor for application in LED-based lighting or display systems.

     

Use of Electrocoagulation with Aluminum Electrodes to Reduce Hardness in Tunisian Phosphate Mining Process Water

This study evaluated electrocoagulation using Al electrodes for removal of non-carbonate hardness in phosphate mining process water. Examination of process parameters identified optimal conditions for hardness removal at pH 7, a NaCl concentration of 4 g/L, a current density of 22.2 mA/cm², an inter-electrode distance of 2 cm, a stirring speed of 450 revolutions per minute, and a treatment time of 30 min. Production of primary coagulant during electrolysis improved removal of both calcite and magnesium hydroxide. The optimized hardness removal was highly efficient, with an overall removal rate of 83.8 % at 30 min of retention time.     

Aggregate planning through the imprecise goal programming model: integration of the manager's preferences

Aggregate planning involves planning the best quantity to be produced during time periods in the medium‐range horizon at the lowest cost. Usually, the production manager seeks a plan that simultaneously optimizes several incommensurable and conflicting objectives, such as total cost, level of inventories, level of customer service, fluctuation in workforce, and utilization level of the physical facility and equipment. The goal programming (GP) model is one of the best known multi‐objective programming models that considers simultaneously several conflicting objectives to select the most satisfactory solution among a set of feasible solutions. In the production planning problem, the goals and the technological parameters are naturally imprecise. Moreover, the existing GP formulations developed in industrial engineering and aggregate production planning do not explicitly incorporate the manager's preferences. The aim of this paper is to develop a GP formulation within an imprecise environment where the concept of satisfaction function will be utilized to explicitly introduce the manager's preferences into the aggregate planning model.     

Design of a RF matching network based on a new tunable inductor concept

We present in this paper a new technique of matching impedances. It consists in replacing a fixed inductor in a matching network by a variable one, and its value is able to change with the load impedance. In the study, the fixed inductance considered is a CMOS integrated one, while the tunable inductance is based on a new Piezomagnetic MEMS concept. A theoretical model of such a tunable inductor is first presented, and then inserted in a matching network in two different ways: inductance value varies either discretely or continuously. The obtained matching networks are compared with a fixed inductor matching network, and simulation results are presented and discussed to validate the presented method and to evaluate the matching efficiency of each matching network.     

Bacillus subtilis SPB1 lipopeptide biosurfactant: antibacterial efficiency against the phytopathogenic bacteria Agrobacterium tumefaciens and compared production in submerged and solid state fermentation systems

Food Science and Biotechnology - Bacillus subtilis SPB1 derived biosurfactants (BioS) proved its bio-control activity against Agrobacterium tumefaciens using tomato plant. Almost 83% of disease...