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During the process of being used, engineering structures will undergo material aging and structural damage with time passing by under the combined influence of internal factors including load, environment and structural material[1], and accumulation of such damages will cause decrease of bearing capacity, durability and reliability. Among various factors influencing the reliability of in-service structures, ultimate bearing capacity plays the decisive role in safety. In this paper, the fourth-order moment of limit state function is inferred through calculation of failure probability of in-service structures, and thus safety and durability of in-service structures can be ensured.

Structure damage identification is a hot research area internationally in recent years. Two damage identification methods based on sensitivity analysis are concluded. A three-tier steel frame structure model is established through utilizing ANSYS10.0, the software of finite element analysis. Through modal analysis of finite element, the frequency and formation before and after damage are obtained. The position of damage of the model is fixed by applying two damage indexes. It is indicated from the results that these two methods are effective for damage identification of the space structure of steel frame.

One of the most important ways to enhance the speed of state estimation is to establish the constant matrix Jacobian. This essay puts forward a new type of orthogonal transformation state estimation method based on Generalized Tellegen's theorem. This paper uses orthogonal transformation method to improve state estimation’s numerical stability, and makes the algorithm enjoy an ideal convergence. Moreover, it has strong compatibility of various distribution measurements. The method put forward in this essay has been verified through IEEE-30 Node System, and the efficiency of it has been fully proved by the example results.

Take full advantage of the PMU's accurate mass measurement data is the effective method to improve the calculation accuracy of power system state estimation. This essay puts forward the state estimation method of power system based on the Taylor series method. It analysis of power system operating conditions based on the real-time measurement of Wide area measurement system, divides the state time, establishes the equation of state of the measurement data by curve fitting method in the period of state time, creates a new state estimation calculation method by Taylor series method, constructs a new voltage characteristic curve calculation method, determines the system state and achieve the continuity of power systems steady-state analysis. The method put forward in this essay has been verified through IEEE-30 Node System, and the efficiency of it has been fully proved by the example results.

One of the most important ways to enhance the speed of state estimation is to establish the constant matrix Jacobian. This essay puts forward the state estimation method of the equivalent current transformation based on the Generalized Tellegen’s Theorem. This estimation method establishes the constant Jacobian matrix without neglecting the secondary factor making use of the Generalized Tellegen’s Theorem, solves the numerical stability problem caused by the establishment of the constant Jacobian matrix in the current state estimation, and has the advantages of a relatively rapid computing rate and an unparalleled astringency. The method put forward in this essay has been verified through IEEE-30 Node System, and the efficiency of it has been fully proved by the example results.

The biggest problem in model checking is state space explosion. Using predicate abstraction, state space of colored Petri net models were abstracted, and an algorithm was proposed to obtain the abstracted state space of a colored Petri net model without its original state space generated. A method to verify safety properties of Web service composition by abstracted state space was proposed. The problem of state space explosion is solved to some extend in this way. Finally an application of the method is illustrated with an example, which its efficiency shown.

Due to their remarkable mechanical properties, carbon nanotubes (CNTs) are considered to be one of the most promising reinforcing materials for the next generation of high-performance cementitious composites. However, the major problem is the highly attractive van der Waals forces between CNTs, which create coherent agglomerates that prove difficult to disperse in cement based materials and reduce the fluidity of the fresh mixture. In this study, the reinforcing effect of highly dispersed multiwall carbon nanotubes (MWCNTs) at ratios of 0.05, 0.1, 0.15， 0.2 and 0.25wt.% of cement has been investigated. The results show that small amount of effectively dispersed MWCNTs can significantly increase the strength of the cementitious

In manufacturing Grid workflow, multiple tasks share a common and limited resource pool. In order to solve task scheduling in multi-process with resource constraints under MG workflow, the Task-Resource Constrained model is set up to descript the assignment relation between task and resource. The framework of the task scheduling and the scheduling policies are also presented that can readjust the tasks according to the priority rules and the time parameters in the process. Then we present a heuristic scheduling algorithm that includes multiple policies. The heuristic scheduling algorithm will update the critical path of DAG (Direct Acyclic Graph) and the beginning time of post-tasks. MG Workflow engine can dynamically schedule the resources according the task requirement. An example is given to illustrate the method at last.