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Construction of a project at a proposed site requires understanding of the geological and hydrogeological conditions for the purpose of engineering design and environmental impact assessment. However, investigation and assessment of the site conditions may be challenging for limestone areas due to the irregular occurrence and development of karst. This paper presents a demonstration of the site investigation and assessment for the karst hydrogeological conditions through a case study of a site with complex lithology. A joint on-site surveying and mapping, drilling, geophysical exploration, supplemented by in-situ and laboratory tests, was implemented in the assessment. Results indicate the site area presents a multiplicity in lithology with steep attitude stratum. Northern part of the site distributed shales suffering different degree of weathering, while the rest areas were developed with carbonate rocks. Fracture zones with north-west and north-east trend were developed at the site, which are prone to form strong runoff zone of the groundwater. No shallow buried river, hall-or corridor-type karst caves were detected at the site, neither of large-scale well-connectivity karst channels. However, many small karst and soil caves were developed at the site, which suggest a post treatment of engineering measures for the purpose of engineering and environmental safety. Based on the distribution of karst ratio calculated from boreholes, the proposed site area can be divided into 3 zones of very-strongly developed zone with a karst ratio around 71.2%, strongly developed zone with a ratio around 26.3% and intermediate-slightly developed zone with a ratio of 15.0%. Characteristics of each sub-zones are analyzed regarding to the general layout and later engineering design of the power plant project. This study provides an example of a joint study for site condition assessment at karst areas with complex lithology. Such an assessment is crucial to the site selection, project layout, engineering design and to later environmental impact assessment.

The lithium niobate integrated optical phase modulator (Y waveguide) is the key device in the digital closed-loop fiber optic gyroscope. However, the half-wave voltage of the lithium niobate changes with the environment temperature, which produces the phase bias drift and ultimately decreases the accuracy of FOG. In this manuscript, the thermal resistor is introduced in the amplification part in the driving circuits of Y waveguide. Due to the characteristic of the thermal resistor, the magnitude of driving voltage on Y waveguide changed with temperature to compensate the electro-optic effects temperature drift of the lithium niobate. This method was proved to improve the performance of fiber optic gyroscopes conveniently in experiment.

In recent years, the phenomenon of vehicle overload in highway transportation is more and more serious. The three-dimensional dynamic FEM was adopted and a three-dimensional simulative model for asphalt pavement with subgrade based on cross-anisotropy under moving load was established by the large-scale finite element analysis software ABAQUS. The response of the stress in the pavement structure was got by using ABAQUS/Standard code. During deceleration, The simulation analysis results under the rated load were compared with those under the different overload ratio. The results show that, under moving load, the surface course of pavement is mainly in three dimension compressive stress state. The horizontal load caused by deceleration has a remarkable effect on the longitudinal stress and the horizontal shearing stress. The stress of the pavement structure under overload is much greater than that caused by the rated load. And the greater the overload ratio, the greater the deviation between them.

The composite laminates are produced by manual molding technology using two guide bar warp knitted fabrics of glass fiber as reinforcement and epoxy resin as matrix. The tensile properties of composites in the course, wale and diagonal directions are tested on the universal material testing machine. The influences of warp knitting stitch structures for mechanical performance of the composites are discussed. The results show that the tensile stress/strain curves of two guide bar warp knitted fabric reinforced composites were nonlinear. The tensile properties of composites possess obvious anisotropic characteristics. The tensile strengths and modulus of the warp knitting fabric composites depend on the yarn numbers bearing load along tensile direction, which are related to the stitches and structural parameters of warp knitted fabrics.

Aiming at the disadvantages of large computing, slow convergence and easily trapping into local minima of traditional BP network, a new method named batch momentum learning algorithm which combining the momentum with batch gradient descent algorithm has been used to be as the learning algorithm of connection weights and threshold of BP neural network, through using this method to forecast the prevalence of plant disease, the convergence speed of BP neural network has been enhanced.

With the development of the petroleum industry ,the separation technology has made progress. The cyclone separator with different structure sizes (such as taper Angle, import hole, overflow hole and bottom hole) are numerical simulated. The separating efficiency are greatly influenced by structural dimension through studied.

In this paper ,we ared study on the reinforcement of a large opening with which the opening ratio is (W)0.8 with numerical calculation. We analyzed the Mechanical characteristics of opened shell It shows the stress concentration is seen clearly on point A which is between Connecting Inside surface of pipe and shell ,and point B, which is between Connecting outside surface of pipe and shell. And the stress concentration on point A is more than on point A when the opening ration(W) is 0.8.And it is calculated reinforcing effect and analyze the limitation when the opening ration by pressure area method（Referred to PAM）.It is obtained the limitation of PAM by comparing numerical calculation to PAM.

The structural morphogenesis methods are numerical methods for seeking various‘good structure shape’ based on mathematical and mechanical principles. The methods are to realize the coordination between structural shape and mechanical properties. In this paper, the height adjusting method and Extended-ESO (extended evolutionary structural optimism) method are successfully applied in practical engineering design schemes, which could be a meaningful reference and a powerful tool to the present design in structural shape and mechanical performance.

In this paper, we study a delayed predator-prey reaction-diffusion system with Beddington-DeAngelis functional response and two stage structure on prey, an immature and a mature stage. The time delays are the time lengths between the immature’s birth and maturity prey species. Under some simple assumptions, using upper and lower solutions method and a comparison principle we prove that the unique constant positive steady states solution is global asymptotic stability. The results shows that the dynamic behavior of solutions to this model is similar to that of solutions to corresponding model without diffusion.

In this paper we study the multi-attribute group decision-making problems and put forward a kind of method. In this method, based on clustering evidence theory, the decision-making information is translated into evidences to support different decision-making program. Then, by the amount of evidences, decision-making program ranking is completed. The method’s character can not only rank the decision-making programs by their merits, but also give each program the probability to be the best. Finally, an example is given to show the rationality and effectiveness of the new method.