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81.
The accurate prediction of cost profiles of future job tasks on the nodes of clusters or grids helps users to select the cost performance profile that best suits their budgets. The current software designed to deploy job tasks uses forecasts of the target computers' future load profiles. Once the job task's future load profile is known, converting it to its cost profile needs further analysis as the cost depends on other factors such as its delays and variable background loads. This paper introduces a new charging mechanism for charging future job tasks, called the Cost Profiling Model. The model has been implemented in a Software Framework and evaluated for its prediction accuracy. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
82.
Line Nybakken Anne-Marit Helmersen Yngvar Gauslaa Vidar Selås 《Journal of chemical ecology》2010,36(3):298-304
Some lichen compounds are known to deter feeding by invertebrate herbivores. We attempted to quantify the deterring efficiency
of lichen compounds against a generalist vertebrate, the bank vole (Myodes glareolus). In two separate experiments, caged bank voles had the choice to feed on lichens with natural or reduced concentrations
of secondary compounds. We rinsed air-dry intact lichens in 100% acetone to remove extracellular compounds non-destructively.
In the first experiment, pairs of control and rinsed lichen thalli were hydrated and offered to the bank voles. Because the
lichens desiccated fast, we ran a second experiment with pairs of ground control and compound-deficient thalli, each mixed
with water to porridge. Eight and six lichen species were tested in the first and second experiment, respectively. In the
first, bank voles preferred compound-deficient thalli of Cladonia stellaris and Lobaria pulmonaria, but did not discriminate between the other thallus pairs. This was likely a result of deterring levels of usnic and stictic
acid in the control thalli. When lichens were served as porridge, significant preference was found for acetone-rinsed pieces
of Cladonia arbuscula, C. rangiferina, Platismatia glauca, and Evernia prunastri. The increased preference was caused mainly by lower consumption of control thalli. Grinding and mixing of thallus structures
prevented bank voles from selecting thallus parts with lower concentration of secondary compounds and/or strengthened their
deterring capacity. We conclude that some lichen secondary compounds deter feeding by bank voles. 相似文献
83.
Marcio Giannini Pereira José Antonio Sena Marcos Aurélio Vasconcelos Freitas Neilton Fidelis da Silva 《Renewable & Sustainable Energy Reviews》2011,15(3):1427-1441
Most developing countries include rural electrification programs in their efforts to improve social conditions. There are, however, several obstacles to the evaluation of such programs and therefore of their social, economic, environmental and energy impacts on the target population, particularly on impoverished communities located in remote areas. Evaluation of the efficacy of public policies aimed at rural electrification in South Africa, China, India and Brazil enables such actions to be quantified and re-considered so as to bolster the sustainability of their planning and implementation and also so as to enable comprehension of the significance of access to electricity in relation to other aspects of the drive to improve living standards. The provision of electric energy amounts to more than access to a public service and should be considered an essential right, in a context of social equity and justice, which permits social integration and the access to other equally essential services. 相似文献
84.
Hidayah Rahmalan Nur Azman Abu Siaw Lang Wong 《Pattern Recognition and Image Analysis》2010,20(4):505-512
Orthogonal moment is known as better moment functions compared to the non-orthogonal moment. Among all the orthogonal moments,
Tchebichef Moment appear to be the most recent moment functions that still attract the interest among the computer vision
researchers. This paper proposes a novel approach based on discrete orthogonal Tchebichef Moment for an efficient image compression.
The image compression is useful in many applications especially related to images that are needed to be seen in small devices
such as in mobile phone. Meanwhile, the method incorporates simplified mathematical framework techniques using matrices, as
well as a block-wise reconstruction technique to eliminate possible occurrences of numerical instabilities at higher moment
orders. In addition, a comparison between Tchebichef Moment compression and JPEG compression is conducted. The result shows
significant advantages for Tchebichef Moment in terms of its image quality and compression rate. Tchebichef moment provides
a more compact support to the image via sub-block reconstruction for compression. Tchebichef Moment Compression is able to
perform potentially better for a broader domain on real digital images and graphically generated images. 相似文献
85.
Ana C. M. de Sena Aquino Juliane M. Pereira Lucas B. Watanabe Edna R. Amante 《International Journal of Food Science & Technology》2013,48(9):1892-1898
This work investigated the pH, titratable acidity and total solids of the cassava starch fermentation water, using the traditional method and a method modified through the addition of glucose. Sour cassava starch production controlled by the characteristic of the fermentation water produced the best product (biscuit specific volume of 7.66 ± 0.41 mL g?1) at 33th day of fermentation in the modified method and at 85th day (biscuit specific volume of 6.53 ± 0.59 mL g?1) in traditional method. But, comparatively to the commercial sour cassava starch (biscuit specific volume of 3.48 ± 0.12 mL g?1), both traditional and modified methods, controlled by titratable acidity of fermentation water, can be retired from the fermentation tank in the 19th and 32th day of fermentation, with biscuit specific volume of 4.75 ± 0.30 and 5.17 ± 0.46 mL g?1, respectively. Determining fermentation time can help to standardise sour cassava starch and to promote future applications of the fermentation water as a raw material. 相似文献
86.
The rehabilitation, repair, and strengthening of concrete structures has increased worldwide with a growing number of systems employing externally applied fiber-reinforced polymer (FRP) composites. However, the service life and effectiveness of FRP repair and strengthening techniques when applied to concrete in corrosive marine environments is still not well understood. This paper presents the results of an experimental study on the corrosion performance of embedded steel reinforcement in cylindrical reinforced concrete specimens with 13 different surface treatment options. Samples were subjected to an impressed current and a high salinity solution. Test variables included the type of epoxy, wrap fiber orientation, and the number of wrap layers. Samples were evaluated for corrosion activity by monitoring corrosion potentials and impressed current flow levels, and by examining reinforcement mass loss and concrete chloride content among samples. Test results indicated that FRP wrapped specimens had prolonged test life, decreased reinforcement mass loss, and reduced concrete chloride content. The performance of wrapped specimens was superior to that of either control samples or those coated only with epoxy. Epoxy type had a significant effect on the performance of samples regarding their resistance to corrosion. It was concluded that carbon FRP wraps were able to confine concrete, slowing deterioration from cracking and spalling and inhibiting the passage of salt water. 相似文献
87.
In this paper, we will present our recent research on the growth and characterization of some Si-based heterostructures for
optical and photonic devices. The heterostructures to be discussed are ZnO nanorods on Si, SiO2, and other substrates such as SiN and sapphire. We will also consider strained Si1−xGex/Si heterostructures for Si optoelectronics. The performance and functionality extension of Si technology for photonic applications
due to the development of such heterostructures will be presented. We will focus on the results of structural and optical
characterization in relation to device properties. The structural characterization includes x-ray diffraction for assessment
of the crystallinity and stress in the films and secondary ion mass spectrometry for chemical analysis. The optical properties
and electronic structure were investigated by using photoluminescence. The device application of these thin film structures
includes detectors, lasers, and light emitting devices. Some of the Si-based heterostructures to be presented include devices
emitting and detecting up to the blue-green and violet wave lengths. 相似文献
88.
This study aims to find a correlation between winter outdoor design temperature (WDT) and mass of the building envelope. The daily variations of the inside surface temperatures and heat fluxes of the walls under various climatic conditions and different wall constructions have been calculated by a computer program based on the response factor technique, which uses variable outside air temperature and solar radiation and constant inside air temperature values as input climatic data. The analysis of the relation between mass of the walls and inside surface heat fluxes resulted with the correction values for winter design temperature (WDTCV) depending on the mass of the wall and on the direction of facades for different climatic zones. 相似文献
89.
Maisara Othman Richard Ritikos Noor Hamizah Khanis Nur Maisarah Abdul RashidSaadah Abdul Rahman Siti Meriam Ab GaniMuhamad Rasat Muhamad 《Thin solid films》2011,519(15):4981-4986
Carbon nitride (CNx) thin films were deposited by radio frequency plasma enhanced chemical vapour deposition (rf PECVD) technique from a gas mixture of methane (CH4), hydrogen (H2) and nitrogen (N2). The effects of rf power on the structural properties of CNx thin films were discussed in this paper. It was found that rf power had significant effects on the growth rate, structural and morphological properties of the deposited films. The point of transition of the growth rate trend marked the equilibrium condition for primary and secondary reactions in growth kinetics of the film with respect to rf power. The films grown at this optimum rf power were most ordered in structure with high surface roughness and had the lowest N incorporation. This work showed that H etching effects and ion bombardment effects increase with increase in rf power and strongly influenced the structure of the CNx films. 相似文献
90.
Güzide alk Nur Pehlivan lknur enver
zelik Pnar alk Tuner H
zdamar 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2004,79(11):1243-1250
Serine alkaline protease (SAP) production in a complex medium based on physically pretreated molasses by recombinant Bacillus subtilis carrying pHV1431::subC gene is described. The effects of oxygen transfer were investigated in 3.5 dm3 bioreactor systems with controls for agitation rate, dissolved oxygen, pH, temperature, and foam formation under two different agitation rates, ie N = 500 and 750 min?1, and four different air flow rates, ie Q/VR = 0.2, 0.5, 0.7, and 1.0 vvm, at a molasses concentration equivalent to initial sucrose concentration (CSo) of 20 kg m?3. The yield values (YX/S, YX/O, YS/O) and maintenance coefficient of oxygen (mO), were calculated. mO decreased with the increase in the air‐inlet rate. Increase in oxygen transfer rate increased the rate of growth and SAP activity, and affected the cultivation time to achieve maximum expression of SAP activity. At Q/VR = 0.5 vvm and N = 750 min?1, SAP activity reached 2250 U cm?3 at t = 36 h. The oxygen transfer coefficient (KLa) and oxygen uptake rate (?rO) were measured throughout the fermentations and their variation with the oxygen transfer conditions determined. New correlations for the calculation of KLa and ?rO are proposed. Copyright © 2004 Society of Chemical Industry 相似文献