A pragmatic pairwise group-decision method for selection of sites for nuclear power plants

A pragmatic pairwise group-decision approach is applied to compare two regions in order to select the more suitable one for construction of nuclear power plants in the Kingdom of Saudi Arabia. The selection methodology is based on pairwise comparison by forced choice. The method facilitates rating of the regions or sites using simple calculations. Two regions, one close to Dhahran on the Arabian Gulf and another close to Jeddah on the Red Sea, are evaluated. No specific site in either region is considered at this stage. The comparison is based on a set of selection criteria which include (i) topography, (ii) geology, (iii) seismology, (iv) meteorology, (v) oceanography, (vi) hydrology and (vii) proximetry to oil and gas fields. The comparison shows that the Jeddah region is more suitable than the Dhahran region.     

Impact of a desalination plant on the physical and chemical properties of seawater, Bahrain

The impact of effluent from the Sitra power and desalination plant (SPDP), Bahrain, on the physical and chemical properties of the receiving water was investigated. Two distinguished zones of the receiving water were recognized. These zones resulted from the presence of the jetty. The length of the first zone is about the same length as the jetty, 70 m. The length of the second zone extends to about 150 m. Seventy five case stations were selected on the receiving water. On the intake side, fifteen stations were considered as control stations. The SPDP effluent significantly changed the temperature and salinity of the receiving water of the first zone. The dissolved oxygen levels vary slightly from the control stations. The jetty was found to restrict the water circulation of the first zone. This restriction caused a delay in the temperature, salinity and dissolved oxygen dispersion. Beyond the first zone, this restriction is removed and the dispersion processes affected the control stations.     

Sex pheromones inCulicoides nubeculosus (diptera,ceratopogonidae): Possible sites of production and emission

This study was performed on virgin females ofCulicoides nubeculosus to determine sites of production and emission of sex pheromone. The ventral abdominal surface is the site of emission of the pheromone. Morphologically there is evidence of the presence of abdominal atrichial areas. The abdominal areas, eight per segment (four ventral and four dorsal), are covered by a cuticle devoid of micro- and macrotrichiae. The dorsal and ventral areas differ considerably in their structure. The dorsal atrichial areas have an unperforated cuticle covering a normal epidermis, whereas the ventral atrichial areas have a cuticle perforated by numerous tubular structures, with a loosely organized procuticle and no underlying epidermal cells. A pair of voluminous cells with the classical ultrastructural characteristics of enocytes is invariably located in the vicinity of the ventral atrichial areas. These cells undergo ultrastructural modifications tending towards involution according to the age of the insects, being correlated with the decrease in pheromone emission by older females. The hypothesis is put forward that enocytes are involved in pheromone production.     

The flavour components of plums: An examination of the aroma components present in the headspace above four cultivars of intact plums,marjorie's seedling,merton gem,NA 10 and victoria

Qualitative and quantitative examination of the aromas above four cultivars of intact plums, using gas chromatography and gas chromatography-mass spectrometry, gave information on 33 components of which linalool, benzaldehyde, methyl cinnamate and y-decalactone were present in regions of the chromatogram associated with plum-like aromas. Comparison of the analytical data with the scoring of plum-like character by sensory means showed that the percentage concentration of these compounds only related approximately to the sensory scores, whereas the percentage of hexanol, the major component present in the extracts, was inversely related.     

A prototype knowledge-based system for material selection of ceramic matrix composites of automotive engine components

A prototype knowledge based system (KBS) for material selection of ceramic matrix composites (CMC) for engine components such as piston, connecting rod and piston ring is proposed in this paper. The main aim of this research work is to select the most suitable material for the automotive engine components. The selection criteria are based upon the pre-defined constraint value. The constraint values are mechanical, physical properties and manufacturing techniques. The constraint values are the safety values for the product design. The constraint values are selected from the product design specification. The product design specification values are selected from the past design calculation and some values are calculated by the help of past design data. The knowledge-based system consists of several modules such as knowledge acquisition module, inference module and user interface module. The domains of the knowledge-based system are defined as objects and linked together by hierarchical graph. The system is capable of selecting the most suitable materials and ranks the materials with respect to their properties. The design engineers can choose the required materials related to the materials property.     

Polarographic reduction mechanism and quantum chemical calculations of some α-arylhydrazononitriles

The polarographic reduction of 2-arylhydrazono-3-keto-3-phenylpropionitriles ( I _a–i) and 2-arylhydrazono-3-ketobutyronitriles ( II _a–i) over a wide pH range is reported and discussed. The mechanism of the electrode process is elucidated and confirmed via coulometric analysis, quantum chemical calculations and IR spectra of the electrolysis products. The molecular structures and molecular orbital energies were calculated and correlated with the redox potentials of these compounds.     

Microstructure and mechanical properties of Al-Al2O3-MgO cast particulate composites

Al-Al₂O₃-MgO cast particle composites prepared by an MgO coating technique were investigated for their microstructural and mechanical property features. In all, sixteen compositions of the composite were subjected to this study. Generally, a uniform distribution of Al₂O₃ particles was observed in the composites. But in the upper half portion of the cylindrical castings, Al₂O₃ particles were found to segregate along the grain boundaries and also within the grain-forming chain-like structures. The microhardness of the base matrix revealed that the retention of submicrometre MgO particles causes dispersion strengthening. In the case of maximum strengthening, the microhardness of the base matrix rises to 35 kg mm^–2 from 19 kg mm^–2 for as-cast pure aluminium. The composites also displayed excellent high-temperature tensile properties up to 250°C (523 K). At the level of 21%V _f retention of Al₂O₃, the composite displayed a UTS value of 110 MN m^–2 with corresponding 0.2% offset yield strength of 65 MN m^–2 and 12% elongation at ambient temperature. At 150° C (423 K) and 250° C (523 K), the composite retains 69% and 53%, respectively, of its room-temperature UTS value. This was the optimum retention of Al₂O₃ and the best composite obtained in the present work. The excellent high-temperature characteristics of the composite are thought to be due to the sum total effect of both the submicrometre MgO particles and the coarser Al₂O₃ particles retained in the aluminium base matrix.     

Use of Position and Feature Cues in Discrimination Learning by the Whiptail Lizard (Cnemidophorus inornatus).

Animals use a variety of cue types to locate and discriminate objects. The ease with which particular cue types are learned varies across species and context. An enormous literature contains comparisons of spatial cue use to use of other cue types, but few experiments examine the ease with which various nonspatial cues are learned. In addition, few studies have examined cue use in reptiles. Thus, the authors compared whiptail lizards' (Cnemidophorus inornatus) ability to learn and reverse a discrimination using either position (left or right) or visual feature cues. Lizards learned and reversed the task using position cues faster and with greater accuracy than using feature cues. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A Wired-AND Current-Mode Logic Circuit Technique in CMOS for Low-Voltage, High-Speed and Mixed-Signal VLSIC

A wired-AND current-mode logic (WCML) circuit techniquein CMOS technology for low-voltage and high-speed VLSI circuitsis proposed, and a WCML cell library is developed using standard0.8 micron CMOS process. The proposed WCML technique appliesthe analog circuit design methodologies to the digital circuitdesign. The input and output logic signals are represented bycurrent quantities. The supply current of the logic circuitis adjustable for the required logic speed and the switchingnoise level. The noise is reduced on the power supply lines andin the substrate by the current-steering technique and by thesmooth swing of the reduced node potentials. Precise analogcircuits and fast digital circuits can be integrated on the samesilicon substrate by using the low noise property of the WCML.It is shown by the simulations that at low supply voltages, theWCML is faster and generates less switching noise when comparedto the static-CMOS logic. At high speeds, the power dissipationof the WCML is less than that of the static-CMOS logic.     

Quality management in the manufacturing industry: Practice vs performance

This study examines the quality management practices in the manufacturing industry in Ireland on the performance of companies. The key findings point to the existence of a moderately positive linear relationship with a correlation coeffiecient of 0.694 between practice and performance. All the available multiple comparison tests conducted showed there is a significant difference in competitive ability between firms with 20–50 employees and theother employment group. From the perspective of competitive advantage, firms are better off being big rather than small. Also the local indigenous firms are at a competitive disadvantage unless jointly owned by foreign partners. Foreign owned firms have better quality management practices with a mean total score of 25% higher than local firms. Furthermore, it appears that being a subsidiary or part of a larger organisation and membership to a quality association contributes to better performance. Competitive sectors like Plastics and Rubber, Chemical and Electrical/Electronics have higher mean total scores than the rest and are above industry average. Firms that have larger export markets have better quality management practices. Finally companies accredited with ISO 9000 (66% of respondents) and or had implemented TQM (19% of respondents) exhibit a wide range of performance and statistically are significantly different than those without.