Analysis of the Single-Crystalline Silicon Photovoltaic (PV) Module Performances Under Low γ - Radiation from Radioactive Source

The present paper is about an experimental evaluation of the terrestrial silicon single-crystalline solar PV module behavior under low gamma radiation. The     

A survey of parallel execution strategies for transitive closure and logic programs

An important feature of database technology of the nineties is the use of parallelism for speeding up the execution of complex queries. This technology is being tested in several experimental database architectures and a few commercial systems for conventional select-project-join queries. In particular, hash-based fragmentation is used to distribute data to disks under the control of different processors in order to perform selections and joins in parallel. With the development of new query languages, and in particular with the definition of transitive closure queries and of more general logic programming queries, the new dimension of recursion has been added to query processing. Recursive queries are complex; at the same time, their regular structure is particularly suited for parallel execution, and parallelism may give a high efficiency gain. We survey the approaches to parallel execution of recursive queries that have been presented in the recent literature. We observe that research on parallel execution of recursive queries is separated into two distinct subareas, one focused on the transitive closure of Relational Algebra expressions, the other one focused on optimization of more general Datalog queries. Though the subareas seem radically different because of the approach and formalism used, they have many common features. This is not surprising, because most typical Datalog queries can be solved by means of the transitive closure of simple algebraic expressions. We first analyze the relationship between the transitive closure of expressions in Relational Algebra and Datalog programs. We then review sequential methods for evaluating transitive closure, distinguishing iterative and direct methods. We address the parallelization of these methods, by discussing various forms of parallelization. Data fragmentation plays an important role in obtaining parallel execution; we describe hash-based and semantic fragmentation. Finally, we consider Datalog queries, and present general methods for parallel rule execution; we recognize the similarities between these methods and the methods reviewed previously, when the former are applied to linear Datalog queries. We also provide a quantitative analysis that shows the impact of the initial data distribution on the performance of methods. Recommended by: Patrick Valduriez     

4-bit adder-accumulator at 41-GHz clock frequency in InP DHBT technology

A 41-GHz 4-b adder-accumulator test circuit implemented in InP double heterojunction bipolar transistor (DHBT) technology using 624 transistors is reported. High clock rates are obtained by combining the logic functions into pipelined latches. The adder-accumulator contains a single-level parallel-gated carry circuit that is used as a step toward reduced power consumption. The carry circuit has a maximum clock frequency of 55 GHz. The accumulator architecture employs modular, pipelined 2-b adders and is cascadable to 2 N-bits. The test circuit includes a 4-b digital to analog converter (DAC) that facilitates demonstration of high-speed operation.     

MESOZOIC COLUMNS BELOW THE SEYCHELLES BANK, WESTERN INDIAN OCEAN

Exploratory drilling on the Seychelles Bank, in a sector west of outcrop granite on Mahé Island, has revealed the presence of substantial Mesozoic colums. Their thicness approaches 3,000m; and total Phanerozoic down to true basement probably exceeds 4,500m. Still greater depths are possible, not only in this drilled NW-most sector of the island arc of the Mascarene Ridge, but also elsewhere along the arc, whose total cross-latitudinal dimension is more than 2,000km. Volcanics, like those in the African borderlands, repeatedly enter the Phanerozoic column of the Seychelles. The young "basaltic basement" of geodynamic theory, consequently, cannot exist on the Seychelles Bank. The same negative may hold true for the whole arc of the Mascarene Ridge and for its marginal waters westward as far back as the African borderlands themsleves. In the domain of exploration, the prime parameter of sedimentary volume is acceptable along much of the Mascarene Ridge, for which reason wells drilled to true basement merit consideration in future drilling. Such wells in central and southern sectors might recover basement rocks whose petrology could offer a strong challenge to present concepts of paleogeography in the whole back-arc area of the western Indain Ocean.     

Disc filtration for separation of flocs from a moving bed bio-film reactor.

A Discfilter with 10 and 18 microm filter openings, respectively, was placed in parallel to a flotation plant for separation of biological flocs from a post-denitrifying Kaldnes Moving Bed Process, the last treatment step at the municipal wastewater treatment plant at Sj?unda, Malm?, Sweden. The effluent concentrations from the 10 and 18 microm filter were 2-5 and 2-8 mg SS L(-1), respectively, which is comparable to, or better than, the flotation plant. Comparison with experiences from activated sludge plants shows that the Discfilter works especially well after the Kaldnes process. Particle size distribution (PSD) studies show that particles larger than the filter openings of 10 and 18 microm are separated with approximately 90% efficiency, whereas most of the smaller particles pass the filter. This fact indicates that the major particle separation mechanism is physical blocking. These findings point to the possibility of improving the prediction of the separation efficiency by combining measurements of turbidity and suspended solids with particle size analysis.     

Autocoro最新技术: e-save

能源成本上涨速度高于纱线价格上涨速度,Autocoro纺纱厂每年的能耗成本约占每年营业额的5％,主要能耗是电能.     

Isolation and Spectroscopic Characterization of Eu@C72

A new Eu-endohedral fullerene cage, namely, Eu@C₇₂, was synthesized, separated, and a single isomer, Eu@C₇₂-I, has been isolated by multi-step HPLC for the first time and characterized by LDI-TOF mass spectrometry, UV-Vis and EPR spectroscopy. Additionally, a second isomer, Eu@C₇₂-II, has been separated by HPLC and identified by LDI-TOF mass spectrometry.     

The ontogeny and significance of infants' facial expressions in the first 9 months of life.

Four studies examined aspects of the differential emotions theory (DET) hypothesis of expressive behavior development. In Study 1, facial-expressive movements of 108 2.5–9-mo-old infants were video recorded in positive and negative mother–infant interactions (conditions). As expected, Max-specified full-face and partial expressions of interest, joy, sadness, and anger were morphologically stable between the 2 ages. Studies 1 and 2 confirmed predicted differential responding to mother sadness and anger expressions and to composite positive and negative conditions. Discrete negative expressions exceeded negative blends, and the amount of both expression types remained stable across ages. Studies 3 and 4 provided varying degrees of support for the social validity of Max-specified infant negative affect expressions. Conclusions include revisions and clarifications of DET. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A histological and histomorphometrical evaluation of screw-type calciumphosphate (Ca-P) coated implants; an in vivo experiment in maxillary cancellous bone of goats

The bone response to different calcium phosphate (Ca-P) coated implants was evaluated in a goat animal model. Two types of plasma spray coatings were applied to a commercially pure titanium (cpTi) tapered, conical screw-design implant (BioComp^®); hydroxyapatite (HA-PS) and a dual coating, consisting of FA and HA (FA/HA-PS). In addition an amorphous RF magnetron sputter coating (Ca-P-a) and uncoated implants were investigated. Forty-eight implants were inserted in the maxilla of 12 adult female goats. After implantation periods of 3 and 6 months, the bone implant interface was evaluated histologically and histomorphometrically. After both implantation periods all plasma spray coated implants were maintained. On the other hand three Ca-P-a and two cpTi implants were lost. Histological examination revealed a better bone response to both plasma spray coated implants. Histomorphometrical evaluation confirmed this finding. At 3 and 6 months significantly higher percentages of bone contact (p<0.001, ANOVA) were measured for both plasma spray coated implants than for the cpTi and Ca-P-a implants, while no significant difference (p<0.05) existed between both implantation periods. Degradation of both plasma spray coatings was observed. Supported by the results, it is concluded that, although Ca-P coatings can improve the performance of dental implants, the presence of a Ca-P coating is not the only important factor for bone healing around implants placed in low density trabecular bone.     

Average intake of anti-oxidant (pro)vitamins and subsequent cancer mortality in the 16 cohorts of the Seven Countries Study

This ecologic study aimed to investigate whether differences in population mortality from lung, stomach and colorectal cancer among the 16 cohorts of the Seven Countries Study could be explained by differences in the average intake of anti-oxidant (pro)vitamins. In the 1960s, detailed dietary information was collected in small sub-samples of the cohorts by the dietary record method. In 1987, food-equivalent composites representing the average food intake of each cohort at baseline were collected locally and analyzed in a central laboratory. The vital status of all participants was verified after 25 years of follow-up. The average intake of vitamin C was strongly inversely related to the 25-year stomach-cancer mortality (r = -0.66, p = 0.01), also after adjustment for smoking and intake of salt or nitrate. The average intake of alpha-carotene, beta-carotene, and alpha-tocopherol were not independently related to mortality from lung, stomach or colorectal cancer, nor was vitamin C related to lung and colorectal cancer.