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Because other consequential damages brought about by the construction delay can not be estimated, so the guarantee period or even ahead of schedule becomes particularly important. The critical path usually determines the progress of the construction. However, because of its own deficiencies, the traditional critical path algorithm cannot accurately describe the overlap between activity and interaction. So, in the paper, matrix method for critical path (CPMM) is designed for CP, and its rules and calculating process are described in detail. Through experiments, the effectiveness of CPMM is proved.

In order to improve GW15 gasoline engine’s power and economy, AVL BOOST/FIRE software has been applied to the simulation of the engine’s one-dimensional and coupled 1D-3D simulation. First, optimal length of exhaust runner was obtained by simulation with BOOST, and proposed two types of structures schemes. Then, the better one was selected for BOOST and FIRE coupling in order to further optimize the exhaust runner according to the numerical simulation results. Finally, the engine performances were verified through experiment. The results indicate that both the engine’s maximal torque and maximal power increase, specific fuel consumption decreases.

The composite of methoxy polyethylene glycol (mPEG) and poly(lactic-co- glycolic acid) (PLGA) thermosensitive hydrogel mixed with different mass raio of hydroxyapatite and β-tricalcium phosphate (β-TCP) were used as bone graft substitutes. The physical properties of a series of composite gels, including the critical micelle concentration (CMC), particle sizes, zeta potential, rheological behavior, morphology of composite gels, and sol–gel transition, were characterized in vitro. These composite gels could form a gel at body temperature and could be controlled easily at room temperature. During the in vitro degradation process, composite gels demonstrated a slight decrease in pH value, a slower degradation rate, less toxicity, and a higher cell survival rate. The biocompatibility of the composite gels was validated by hemolysis test. In vivo animal studies demonstrated both radiographic and gross bone union when the ratio of HAP/ β-TCP was 7:3.

Because of its unique role in the information flow analysis, the design structure matrix (DSM) is widely used to the optimization of the organization, parameter and other aspects. Its matrix representation, the dynamic features make it possible that be applied to optimization of business processes, but so far the DSM in the business process application is also rare. In the paper, DSM is tentatively applied to topological sort in the business process and is compared to the traditional topological method. These explorations for the application of the DSM in the optimization of business processes are positive.

This paper concerns the dynamic modeling and vibration control of a space two-link flexible manipulator. Two types of PZT actuators, PZT shear actuator and torsional actuator, are used to suppress the bending-torsional-coupled vibration of the space manipulator. Using extended Hamilton’s principle and the finite element method, equations of motion of the space flexible manipulator with PZT actuators and tip mass are obtained. Based on modal analyze theory, the state space model of the system is then used to design the control system. A linear quadratic regulator (LQR) controller is designed to achieve vibration suppression of the space manipulator system. From the numerical results, we can get that the proposed controller has a suitable and efficient performance suppressing the bending-torsional-coupled vibration of the space two-link flexible manipulator.

Through analyzing the specialty and limitation of the current driving simulators, the main factors affecting fidelity of driving simulators are summarized. Then, a new driving simulator of high fidelity based on the multi-body dynamics is proposed, with focus on the dynamics modeling and the road feel. Furthermore, a control algorithm of the road feel is designed and by the means of co-simulations in MATLAB/Simulink and ADAMS environment, the measuring steering wheel torque proves the control algorithm of road feel is reasonable. The control algorithm has been put into practice and got satisfactory results.

In order to fulfill the requirement of vehicle dynamics performance and real-time capability in driving simulator, modeling and simulation method of a four-wheeled vehicle model based on multi body dynamics software Vortex was studied. Fundamental construction and dynamics properties of the model such as body, chassis, wheels, power train, suspension and tyre model were described. The model was tested to simulate on the C grade of road. The results indicate that the model and simulation method can well represent vehicle dynamics performance and high real-time capability of simulation, and is worthy to apply to driving simulator in the future.

Real-time calculation of dynamics model is one of the key technologies in the driving simulator. A multi-body dynamics model of tracked vehicle was developed using the Vortex software. The sinusoid superposition method was exploited to extend the 2-D road surface spectrum and to establish the 3-D road roughness elevation data in accord with the state standard. Then the elevation data were imported into Multigen Creator to construct the 3-D virtual road. Including the vehicle model, the virtual reality system was created. In the simulation of riding comfort, the responses of the vehicle were obtained when the vehicle traversed under road excitation of D grade with constant speed. The result shows that the system offers good immersion and real-time performance. It is feasible to be applied to the tracked vehicle driving simulator.

In driving simulator, the driver manipulating the steering wheel can not only be feeling authentic as the real vehicle but also get additional information of the vehicle state and road conditions. For this purpose, a steeling wheel system was detailed designed. A bicycle model was used to analyze the dynamic behaviour of a simplified four-wheel vehicle model and applied to compute the reaction torque. After modeling the steering column and the feedback motor, the state equation of the steering wheel was deduced. The control without PID, with ordinary PID and RBF network PID were adopted to control the feedback motor to generate desired torque. Simulation in matlab/simulink shows that the steering wheel has good performance and the RBF network PID controller has better performance and can satisfy the requirement of the reaction torque. This study will be a guide research for future driving simulator.