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The water temperature distribution and spatio-temporal variation law of the reservoir have a great influence on the water quality and ecological environment of the reservoir, and it is also an important temperature boundary condition for the design of concrete dam of hydropower station project, which is of great significance for the optimal design and operation of the reservoir. There are many factors affecting the water temperature of the reservoir, and it is difficult to predict the water temperature distribution accurately because of the lack of data and experience. In this paper, a numerical analysis model is established for the reservoir of a hydropower station on the Nam Ngum in Laos, and the water temperature of the reservoir is calculated and predicted, and the water temperature distribution in the reservoir and the water temperature distribution in front of the dam are analyzed and discussed. The results show that the solar shortwave radiation is the main factor affecting the temperature stratification of the reservoir. The stable low temperature layer of the reservoir is not obvious, but there is a tendency to form stratification. The research results can provide water temperature value for the design of concrete dam of the hydropower station and provide reference for the prediction of the water temperature of other similar reservoirs.

By means of heat treatment and creep property measurement, an investigation has made into the creep behaviors of a containing 4.5% Re nickel-base single crystal superalloy at high temperature. Results show that the elements W, Mo and Re are enriched in the dendrite arm regions, the elements Al, Ta, Cr and Co are enriched in the inter-dendrite region, and the segregation extent of the elements may be obviously reduced by means of heat treatment at high temperature. In the temperature ranges of 1070--1100 °C, the 4.5% Re single crystal nickel-based superallloy displays a better creep resistance and longer creep life. The deformation mechanism of the alloy during steady state creep is dislocations slipping in the γ matrix and climbing over the rafted γ′ phase. In the later stage of creep, the deformation mechanism of alloy is dislocations slipping in the γ matrix, and shearing into the rafted γ′ phase, which may promote the initiation and propagation of the micro-cracks at the interfaces of γ/γ′ phases up to the occurrence of creep fracture.

With rapid tempo of development in the information technology, design model of information network based on three-layer structure and WCF could solve problems about dormitory managing work which relies on its merit as to independence of programming language and platform. It makes programmers’ distribution and collaboration of tasks more effective to apply key technology of three-layer structure and Web Service to student dormitory management system’s design and implement. Therefore, developers of system can pay more attention to the relative business logic in order to reduce difficulty of maintenance in late stage of software development life cycle. Moreover, it does not need artificial intervention to realize RFID which has speedily and convenience operation. In this case, efficiency of managing work and unity of system data can be guaranteed.

With the improvement of human environment protection consciousness, and at the situation of the high price of crude oil.Hybrid electric vehicle has gradually become the development trend of the future.Synchronization of power supply of the generator and battery is a necessary condition for forklift work stability. The system outputs SPWM signal by single chip microcomputer AT89C51 as the core chip,implementation of the trace function of frequence and phase,implementation of the defensive function of under-voltage and over-current.The circuitry electrical system is simple and flexible control.Hybrid forklift is verified its effectiveness by simulation analysis through multisim and matlab.Implementation of synchronous control of hybrid systems.

Although the fly ash concrete with machine-made sand (MSFAC) was widely used in recent years in China, it was lack of studies on relations of compressive strength at different ages. According to the specification of Chinese standard, there are three ways of admixing fly ash (FA) into concrete, i.e. the additional admixing, the equal-mass replacing cement and the over-mass replacing cement. In this paper, 56 groups test data with additional admixing FA, 98 groups test data with equal-mass replacing cement and 86 groups test data with over-mass replacing cement for MSFAC are summarized from published references. Three linear formulas and Slatter formulas are fitted and compared for MSFAC by the different methods of admixing FA, all of them have good fitness with test data. The compressive strength at 28d can be predicted by the compressive strength at 7d with linear formula and Slatter formula for MSFAC.

To meet the requirement of machine-made sand application in concrete structures, it is necessary to understand the bond properties of steel bar with machine-made sand concrete (MSC). Therefore, the experimental studies were carried out on the bond of plain steel bar with MSC by the central pull-out test method. Three specimens were cast as one group, 6 groups were tested considering the changes of strength grade of MSC and ordinary concrete. The bond-slip curves were measured and analyzed. The results show that the bond slip begins at the tensile side and transfers gradually to the free end before the entire slip turns up along the interface of plain steel bar and surrounded concrete, the largest average bond stress, i. e. the bond strength of plain steel bar corresponds to the initial entire slip of plain steel bar. With the increasing strength grade of MSC and ordinary concrete, the difference of slip at tensile side and free end becomes greater. Comparing that only appears in ordinary concrete with higher strength, the larger slips turn up while the bond stress reaches the largest for the plain steel bar in MSC. Larger scatter of bond strength is between specimens in the same group. Some plain steel bars yields with the beginning of entire slip along the interface.

After the 4-bromo-3,5-difluorophenyl acrylamide (BDPA) and acrylic acid were introduced into the epoxy acrylate (EA), the photosensitive epoxy acrylate (EFBDPA) with good performance was prepared through chemical graft modification. The structure of EFBDPA was confirmed by FTIR and1H-NMR. When the content of BDPA in EFBDPA was 20%, the cured coating of EFBDPA had better performance than the unmodified EA cured coating, its tensile strength, 80 % decomposition temperatures and the residual carbon ratio were improved 86%, 5.7 °C and 4.2 %, respectively.

A web replay method is proposed in this paper for highlights in soccer videos. Firstly, automatically detection and fine-grained semantic annotation are introduced for soccer highlights. Secondly, an adaptive grass color model and several heuristic rules are used to improve the performance of the method. Finally, a database for highlights is established for web service. Experimental results show that the proposed method has excellent analyzing speed, accuracy and practicability.

Based on independent research and development of a CFRP tendons wedge-type anchorage, the shear tests of six CFRP external prestressing concrete beams were done. Among them, CFRP external tendons of three pieces were installed in straight line while other pieces were installed in curved line. The results of experimental research show that shear behaviour of concrete beams prestressed with CFRP external tendons are the similar process to the traditional prestressed reinforced concrete beams. They go through the elastic stage, the stage of crack extension, the yield stage of internal hoop reinforcements at the intersection of inclined cracks and the failure stage. When external CFRP tendons are arranged in the same situation, the cracking load and the shear capacity of concrete beams prestressed with CFRP external tendons reduce gradually along with the increase of shear-span ratio,.When shear-span ratio is equal, the cracking load and the shear capacity of concrete beams prestressed with curved arrangement of CFRP external tendons are larger than those of concrete beams prestressed with straight arrangement of CFRP external tendons. Compared with traditional concrete beams prestressed with external steel bars, due to elasticity modulus and shear modulus of CFRP tendons are both smaller than those of steel bars, the mid-span deflection of concrete beams prestressed with CFRP external tendons at the time of shear failure is bigger than that of traditional concrete beams prestressed with external steel bars under the same circumstance.

Tests were carried out to study the concrete attacked by magnesium sulfate solution. The concrete specimens were exposed in the magnesium sulfate solution with three different concentrations for 360 days. At the exposure times of 90 days, 180 days, 270 days and 360 days, the properties of concrete such as the mass change, the compressive strength and the tensile strength were measured, and the contents of sulfate-ion diffusing into different depths of concrete were determined. Their changes with the solution concentration and the exposure time are analyzed in this paper, which could be used as reference for the protecting of concrete against the attack of magnesium sulfate.

To meet the requirement of machine-made sand application in concrete structures, experimental studies were carried out on the bond of plain steel bar with Machine-made Sand Concrete (MSC) by the central pull-out test method. Three specimens were cast as one group, 14 groups were tested considering the influence of concrete strength, bond length and stone powder content in machine-made sand. Based on the experimental research, the characteristic values of bond-slip curve such as the initial-slip and ultimate bond stresses with corresponding slips are statistically analyzed, the bond-slip constitutive relations between plain steel bar and MSC were obtained.

Based on the experimental studies, finite element models were built using ANSYS software to simulate the bond properties of steel bars in machine-made-sand concrete (MSC), which considered the nonlinear bond behavior of interface between steel bar and MSC. The concrete strength and the bond length of steel bar are considered as the main parameters for calculation. The complete bond-slip curves of plain and deformed steel bars are well simulated comparing those obtained from the experimental studies. The study gives an theoretical method to analyze the bond properties of steel bar in MSC.

The automatic assembly system of saw chain is designed to solve the low efficiency and poor quality of its assembly process according to the actual requirements of production. Firstly, the structure of saw chain and its automatic assembly requirements are analysed. Secondly, the different design plans on assembly process and assembly method are proposed and compared. Finally, the automatic assembly system of saw chain is designed, which is composed of feeding device and clamp positioning system. This system can not only realize the automatic assembly of saw chain, but also improve the assembly quality and prolong the using life of saw chain.

To recognize the interrelationship of plastic deformation with strain and time, uniaxial tension relaxation experiments of PVC coated plain weave membrane were executed along the warp and weft direction, while plastic deformation of the specimen were measured in 1 year. Using multiple functions from the product of both the strain difference (strain- critical strain) power function and the time power function, the experimental data was studied on a multiple regression analysis. It was concluded that the model had better fitting results. At the same time, an instantaneous plastic and a relaxed plastic term of the total plastic deformation were analyzed. It was showed that the instantaneous deformation was the main part of the plastic deformation, that the relaxed plastic deformation was the minor part of the plastic deformation, and the relaxed plastic deformation would become smaller and smaller with time extension.

The development of economic has cause many problems about emerging and dense concentration of High-rise buildings in Baotou,so that the urban natural environment, urban living environment, urban spatial structure ,the urban cultural environment have been greatly affected.Therefore, this article discusses the problem about high-rise buildings from the perspective of the urban environment, with an aim to find a harmonious development method on high-rise buildings and urban environment.

Experiments were conducted to study the effects of source rock state and stone powder on freeze-thaw resistance of concrete with proto-machine-made sand, the strength grade of concrete was C50, the source rock states were gravel and crushed stone, the contents of stone powder in sand were 5%, 9% and 13% respectively. The values of relative dynamic elastic modulus and mass of concrete at different freeze-thaw cycle times were measured, the reduction of relative dynamic elastic modulus and mass loss were calculated to evaluate the freeze-thaw resistance of concrete. The results show that freeze-thaw resistances are controlled by the reduction of relative dynamic elastic modulus of concrete, which are good of concrete with proto-machine-made sand of gravel and crushed stone, and increases with the increasing content of stone powder in sand made of gravel. The reasons leading to difference of freeze-thaw resistance of concrete with sand made of gravel and crushed stone are discussed.