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In order to ensure the safety of the curved girder bridge operations, the actual testing is necessary to determine the impact of various factors on the horizontal offset of the bridge bearing against bearing defects. In this paper, finite element analysis with Midas/Civil is applied to each factor separately to get the spherical bearing offset of various factors which compared with the actual displacement analysis, and get the impact the bridge itself gravity, the vehicle load generated by the centrifugal force and the temperature load to the spherical bearing horizontal offset. The analysis results show that the main reason of the spherical bearings horizontal offset is climb shift of the bridge in temperature load. On this account, make effective measures for the protection and repair of bridge to ensure the safety of the bridge operations.

Custom tooling is an effective method to improve surface roughness, geometrical accuracy, machining efficiency, and consequently the core competitiveness of the final products in very complicated freeform creation and micro/nano machining, such as the propeller, blisk and ductile-mode machining of hard and brittle materials. However, commercially available CAM systems have limitations in generating CNC programs for these customized tools due to considerations for special custom tool fabrication processes. Therefore unique CAM system is needed and consequently dedicated CAD sub-system is the prerequisite for such CAM system. In this paper, the dedicated CAD sub-system design is studied to extend the authors’ previous study. The characteristics of customized tools are summarized and analyzed. Then, the functions for the dedicated CAD sub-system are analyzed and defined. Finally, the system is designed and developed by using VC++, Open CASCADE, and ActiveX Data Object techniques.

A thick Fe-based amorphous and nanocrystalline composite coating was prepared by in-situ tungsten inert gas (TIG) cladding method. The results show that the cladding coating mainly consists of amorphous phase and nanocrystalline grains. The microstructure study shows that the Fe-based composite coatings have unique microstructure including nano-sized grains surrounded by nano-scale amorphous shell layer (encapsulated structure) and the homogeneously distributed dendrites/cellular crystals. The unique microstructure gives rise to the superior micro-hardness and wear resistance of the coating. The Fe-based coatings have great potential as promising wear-resistance structural materials used in electric power and cement industry.

At present, gas disaster is one of the main problems for Chinese coal industry. The prevention and control of gas accident is an important part of coal mine enterprise production safety. This paper uses wireless sensor network to collect the coal mine gas concentration parameter, transmits and stores the data to the server of gas monitoring system by information fusion of sink, and synchronously displays the data to the client in the state of three-dimensional space. When the gas concentration of monitored coal mine roadway is greater than the limit, the sound and light alarm will be trigged and the alarm area will be displayed. In the meantime, the information of contingency plan will be provided. The system gives a strong technical support for the early warning and controlling of gas disaster and provides a reference for the prevention of gas accidents in coal enterprises.

The homogeneous rare-earth catalytic system was used to initiate the polymerization of isoprene, and a novel IR was synthesized with high molecular weight and narrow molecular weight distribution. According to the self-developed rare-earth IR properties, a study on IR and IR/NR blend was made. The effect of JiHua rare-earth IR on the vulcanization characteristics and dynamic properties in IR/NR blend was investigated and compared with IR (SKI-3) synthesized with titanium catalyst system and rare-earth isoprene rubber (SKI-5) made in Russia. The results showed that JiHua rare-earth IR to be developed independently was a novel synthetic rubber with excellent comprehensive performance, and it can be used independently and partly substitute natural rubber to make tire. In the IR/NR blend, Not only vulcanization characteristics and the safety in operation for NR was greatly improved, But also dynamic properties of vulcanizates such as dynamic cutting resistance, abrasion resistance, wet-skid resistance and aging resistance were improved to different degrees. These properties reach or surpass the level of the foreign similar products like Russia SKI-3 and Russia SKI-5.

An efficient Integrated Bandwidth Allocation Scheme (IBAS) is proposed to serve the lower priority requests can be early assigned the bandwidth without waiting too long. These will speed up the channel capture by priority data to support the multimedia traffic over DOCSIS-compliant cable networks. The efficiency of IBAS is investigated by simulations. The results show that by adopting IBAS can not only shorten the collision period but also minimize the average request delay of lower priority requests. Performance has been improved in throughput and delay compares to the current DOCSIS specifications.

This paper studied the borehole stability in Liulin bituminous core reservoirs during under-balanced drilling. The equivalent depth method was applied to study the formation pore pressure. The floor drain test method was applied to study the ground stress. Core strength experiments combined with logging data were used in the establishment of core strength predicting model. Mechanics analysis model was founded to study the borehole stability in the core reservoir. According to the studying and analyzing results, the under-balance drilling in Liulin coal reservoirs enjoys good borehole stability.

A newly constrained multi-objective differential evolution optimization technique (CMODE) for security constrained economic/environmental dispatch (EED) was proposed. The proposed CMODE evolved a constrained multi-objective version of differential evolution (DE) by employing the traditional multi-objective differential evolution (DEMO) and constrain handle technique to balance the search between feasible region and infeasible region. The proposed CMODE method had been applied to solve the security constrained EED problem. Experiments had been carried on a standard test system. The results demonstrate the high efficiency of the proposed method to solve security constrained EED problem, and the necessary of taking security constrains into consideration.

Simvastatin, as one of the HMG-CoA reductase inhibitors for lowering lipids, has been demonstrated its potential benefit in bone formation, which was, however, conflicting and inconclusive in vivo studies. Thus, we performed this study to assess the in vivo effects of simvastatin on bone formation. Six-week old rats were administered with simvastatin (20 mg/kg/d) or vehicle for 6 or 9 weeks. All animals were sacrificed one day after the final administration. The left femora were removed for the measurement of bone histomorphometry and bone mineral density (BMD).Compared to the control groups, on both 6th week and 9th week, bone mineral density and bone histomorphometry detected no significant differences in bone mass and microarchitecture in simvastatin treatment group, as well as bone formatin/resorption parameters. These results indicate that simvastatin had no positive effect or impact on bone in rats administered with high dose simvastatin (20 mg/kg/d) for 6 or 9 weeks.