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Materialized view is an effective mothed for improving the efficiency of queries in data warehouse system,and materialized views selection problem is one of the most important decisions in designing a data warehouse.This paper begins with a brief introduction to materialized view and study of the existing materialized viewalgorithm.Then in order toselect an appropriate set of views that minimizes total query response timeand the cost of maintaining the selected views under a limitedstorage space, a hybrid algorithm combined with the advantages of ant colony algorithm and immune genetic algorithm is proposed.Inaddition,analyze the shortcomings of this algorithm and propose some improvement ideas, which optimize the efficiency of algorithm to some extent.

Keyer technology is the mainstream of computer graphics technology, this article first made a simple statement of the keyer technical background and application , then divided matting technology into two categories: hard keyer and soft keyer and some of their commonly used algorithms, at the same time this article pointed out the technical problem of the existing keyer technology and some improvement methods, finally combining with the commonly used several methods, had a video as experiments and showed the results.

Image matting is a technology to extract interested prospects or subtract the background from videos or images. It is more and more widely used in television and movie production, virtual studio, network education, video monitoring and many other fields. Mainly aims at the pure-colored background of virtual studio, this paper proposed a real-time video matting algorithm based on chroma key. The algorithm used morphology operations to process the edge of matting images effectively, practiced in situational teaching system. It satisfies the real-time requirement on the premise of quality assurance. Finally, this paper considers some existing algorithm problems and puts forward feasible improvement methods.

Effect of nucleation agentboth on the toughness and the orientation of PET were studied. Rapid nucleationof melted PET caused by nucleating agent resulted in the decrease in grain sizeand it can improved the toughness of the PET. Both the elongation and the areaunder stress-strain curves of the PET strapping band increased significantly.Among these agents, 0.5wt% Aclyn is the most effective for elongation increaseand the tensile strength is not changed for PET/Aclyn strapping bands. Both thedecrease in orientation degree and the increase in crystallinity were observedafter adding nucleating agents in PET strapping bands. The increase in theresidual ratio of the relaxation stress with the increase of the crystallinity proved that the crystallization could inhibits thedevelopment of the stress relaxation.

The method to analysis the rheological property of the crosslinked polymer microspheres is presented in this paper. The flow curves and hysteresis loop areas of different swelling time and different mass concentrations of microspheres gotten. Through the above experimental data, the flow pattern and the time-dependent property are judged. Combined with the environmental scanning electron microscope images of microspheres, we can draw the conclusion that the concentration has obvious effects on the rheological property of the microspheres.

In this paper, different mathematics models are applied to research the reasonable pricing of the cloud computing software products on the SaaS platform and explore the sales price of the cloud computing software products with the maximum total profits. These information can be the reference for decision-makers to determine the pricing strategy. The aim of this paper is for the cloud computing company to provide the majority of users with the inexpensive and excellent softwares and services, which can make the company dominate the cloud computing market quickly, gain the huge profits in the sustainable development manner and consider the interests of the company, users and the society.Keywords: clouding computing, SaaS, pricing and charging, mathematical analysis

The content of total lipids in Pacific white shrimp head was higher than those find in other shrimps. A process to extract lipids from Pacific white shrimp waste (head) was developed. Supercritical fluid extraction was used and the effects of temperature, pressure, CO2flow rate and extraction time on extraction yield and composition of the fatty acids were investigated. The extraction yield had little dependence on pressure, temperature and CO2flow rate. However, the pressure and temperature conditions affected the composition of the fatty acids. Addition of entrainer can increase the extraction yield significantly (P

Ecological industry were qualitatively and quantitatively studied from the price perspective in this paper, because price study before it comes into being is more important than after it happened. We proposed that price should guide and constrain people’s choices. Then chose four subsystems: economic, social, environmental, energy, constructed price and interest evaluation indexes systems, used analytic hierarchy process, quantitatively analyzed interest and price of enterprise’s project based on experts' experience, gave every index weight. At last, accounting to price and interest of different project, made decision of enterprise.

In recent years, oil spill happens in river frequently, which has serious impact on the ecological environment and human health. So it is very important to conduct research on the pollution control technologies of oil spill in the river water. This paper analyzes the domestic and overseas existing oil spill pollution control technologies and puts forward the method combining oil recycling machine and oil dispersant to deal with the pollution caused by oil spill in Changqing Oilfield. Through the comparison, the turntable oil recycling machine and the SC-Y17 oil dispersant are finally selected. According to the experiment, we find that temperature has a great influence on the effect of oil dispersant and measures should be taken to improve the property to make it can adapt to the requirements of the low temperature environment.

In water diversion project and water delivery project, horseshoe cross-section and circular cross-section are commonly used. The hydraulic elements of nonstandard horseshoe shape and circular shape are difficult to calculate because of their complex section. This article gives the formulas of hydraulic elements and iterative formulas of normal depths and critical depths of horseshoe shape section composed of 6 arcs and 2 kinds of irregular circular shape section by mathematical derivation. And on the basis of the relation with depth, normal depth and critical depth, we can estimate the type of water surface profile. It can be applied in calculation of water surface profile 81.68 km Qinling tunnel of south water to north project. The formulas of normal depth and critical depth and hydraulic elements can be used in other similar water delivery project.

The phenomenon of wax deposition is an extremely important issue in the petroleum industry. Researching it is of great help for the oil exploration, gathering, and transportation. This paper described the phenomenon of wax deposition, discussed the mechanism, analyzed the influencing factors and proposed the positive significance of the phenomenon of wax deposition on crude oil production and safe operation in oil gathering and transportation pipeline.

With L-glutamic acid as raw materials, N-carboxy-L-glutamic acid-benzyl-anhydride (BLG-NCA) was synthesized by triethanolamine. With triethanolamine as the initiator in the anhydrous dichloromethane, ring-opening polymerization of BLG-NCA was initiated, poly-l-glutamic acid benzyl ester was obtained. The amount of initiators, molar ratio of monomer/initiators, reaction temperature and reaction time to the effect of poly-l-glutamic acid benzyl ester in the ring-opening polymerization of BLG-NCA were studied. At last, poly L-glutamate was got, after the debenzylation in HBr solution. Through infrared spectroscopy, Ubbelohde viscometer, 1H NMR spectra, polymerization product was characterized and analysized. Results showed that in dichloromethane, ring-opening polymerization of BLG-NCA could be initiated by triethanolamine.

The theoretical backing of the similarity laws obtained from dual dimensionless parameters of the bed-form classification diagram is given by solving the equations of similarity conditions which is obtained from 1-Dimensional equation of motion, continuity equation, bed deformation equation and the formula of bed load transport. Secondly, the validity of the similarity laws is confirmed by comparing the bed form of distorted model experiment with that of undistorted model experiments performed by Hokkaido Development Bureau (H.D.B.). And also the fact that the height of bar in a gentle curved river channel can be estimated by the result of distorted model of straight flume is found.

Flow characteristics of horizontal two-phase gas-liquid stratified flows in condensate natural gas pipeline are studied through both air-water and air- natural gas condensate experiments on the large-scale multiphase experimental loop. Based on measurement and observation of flow pattern, “apparent rough surface” (ARS) model is selected to calculate frictional pressure gradient with gas-liquid momentum balance equations. The predictions of the models are compared with the data measured in the experiment. Some results of pressure gradient are obtained, so ARS interfacial shape is recommended in horizontal two-phase gas-liquid flows with low liquid loading.

Bacillus subtilis is potential to play an important role on biological control of aflatoxin-producing fungi. The liquid fermentation medium of Bacillus subtilis LN for production of bioactive metabolites inhibitory to mycelial growth and aflatoxin biosynthesis was optimized by single factor experiments. The results showed that optimum carbon source was glucose, the optimum nitrogen source was soy peptone, and the optimum inorganic salt was MgSO4.These screened optimal carbon, nitrogen and inorganic salt sources could be used for high yield fermentation of bioactive metabolites for developing biopesticide against aflatoxin contamination in foods.

With L-glutamic acid as raw materials, N-carboxy-L-glutamic acid-benzyl-anhydride (BLG-NCA) was synthesized by triphosgene. With aniline as the initiator in the anhydrous dichloromethane, ring-opening polymerization of BLG-NCA was initiated, poly-l-glutamic acid benzyl ester was obtained. The amount of initiators, Molar ratio of monomer/initiators, reaction temperature and reaction time to the effect of poly-l-glutamic acid benzyl ester in the ring-opening polymerization of BLG-NCA were studied. Through infrared spectroscopy, gel permeation chromatography (GPC) analysis and characteristic viscosity method, polymerization product was characterized and analysized. Results showed that in dichloromethane, ring-opening polymerization of BLG-NCA could be initiated by aniline, which expands greater scope of the initiators of poly-l-glutamate to aromatic compounds, and the introduction of the active group provided by aromatic compounds make it possible for the advanced development of block copolymer with poly-l-glutamic acid as a basic unit.

It is very important for reservoir management to estimate the sedimentation amount deposited in a reservoir. Firstly, the formula for estimating the bed load transport rate in the bed of sand waves of prototype by model experiment was derived based on the similarity of grain Froude number; Secondly, several model experiments that the bed forms is similar with the prototype were carried, and the formula was verified. As a result, when the ratio of grain diameter in the prototype and model is great enough, and the bed forms in the model is similar with that in the prototype, a satisfactory result can be obtained by using the estimation formula for estimating the bed load transport rate of the prototype that sand waves occur in the bed.