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Corrosion of longitudinal reinforcement and stirrup in reinforced and prestressed concrete beams is very common for structures and infrastructures, which is one of the main reasons for the decrease in stiffness and durability of structure. In order to evaluate the influence of corrosion of different types of stirrups on the bearing capacity of the prestressed concrete beam, the method of using electricity to accelerate corrosion was adopted. Load experiment on 4 corroded prestressed concrete beams with different corrosion rates and different stirrup types was carried out. In this paper, reduced scale model beams were designed based on the 5 × 50 m simple-continuous box girder of the Donghai Bridge. The results show that for prestressed concrete beams with different corrosion rates and stirrup types, the load-deflection curve can be divided into an elastic stage and a plastic stage. The corrosion of longitudinal bars and stirrups will reduce the flexural capacity, but the overall decline is not obvious. When the corrosion rate is 10%, the bearing capacity of the ordinary stirrup specimen decreases by 6.1%; epoxy-coated stirrup specimen decreases by 4.9%; stainless stirrup specimen has nearly no change. The influence of different types of stirrups on cracking load, deflection, and bond-slip behavior is discussed.

Based on the computer regression analysis method, this article first analyses the urbanization system, resource system, and environmental system on the premise of carefully analysing the connotation characteristics of new-type urbanization, resource and environmental carrying capacity, and response relationships. Mechanism of action. Furthermore, an index system for the response relationship of urbanization resources and environmental carrying capacity was constructed, and the urbanization level and resource and environmental carrying status of 10 provinces and cities in China were evaluated from 2000 to 2015. The characteristics of the change in the response relationship of each province and city are divided into three types: “positive response type”, “positive-negative response type” and “alternative response type”. Finally, through multiple regression analysis, explore the factors that affect the response relationship to show different evolutionary trends.

This paper uses computer entropy calculation method to take the Yangtze River Economic Belt as the research object, combined with the theory of resource and environmental carrying capacity, sustainable development, and coupled systems, selects 11 provinces and cities in the Yangtze River Economic Belt as the research object, and establishes a time-space evolution cycle. Coupling model of capital and resources environment. The research results show that during the five-year period, the carrying capacity of regional environmental resources has shown that the eastern and western parts are better and the central part is weaker. Over time, the carrying capacity has gradually improved. In terms of sustainable development, the eastern coordination ability is strong, and the central and western areas are weak. In terms of time, resources, environment and economy are developing in a more coordinated direction. In view of the above, the paper puts forward corresponding development suggestions, hoping to enhance the development potential of the Yangtze River Economic Belt.

This paper presented a new aerial platform-AERORail for rail transport and its structure evolution based on the elastic stiffness of cable; through the analysis on the cable properties when the cable supported a small service load with high-tensile force, summarized the theoretical basis of the AERORail structure and the corresponding simplified analysis model. There were 60 groups of experiments for a single naked cable model under different tensile forces and different services loads, and 48 groups of experiments for the cable with rail combined structure model. The experimental results of deflection characteristics were compared with the theoretical values for these two types of structures under the same conditions. It proved that the results almost met the classical cable theory. The reason is that a small deflection was required when this structure was applied. After the tension increments tests with moving load, it is verified that the relationships between the structure stiffness and tension force and service load are simple. Before further research and applications are made, these results are necessary for the determination of the reasonable and economic tensile force, allowable service load for the special span length for this new platform.

Estimation of Distribution Algorithm (EDA) is a class of evolutionary algorithms which construct the probabilistic model of the search space and generate new solutions according to the probabilistic model. Particle Swarm Optimization (PSO) is an algorithm that simulates the behavior of birds flocks and has good local search ability. This paper proposes a combination (EDAPSO) of EDA with PSO for the global optimization problems. The EDAPSO proposed in this paper combines the exploration of EDA with the exploitation of PSO. EDAPSO can perform a global search over the entire search space with faster convergence speed. EDAPSO has two main steps. First, the algorithm generates new solutions according to the probabilistic model. Then, EDAPSO updates the whole population according to improved velocity updating equation. EDAPSO has been evaluated on a series of benchmark functions. The results of experiments show that EDAPSO can produce a significant improvement in terms of convergence speed, solution accuracy and reliability.

Inspired by the search method of harmony search algorithms, we propose an other version of improved harmony search(IHS)algorithm to solve integer programming problems. This paper designs a novel improvising strategy which is beneficial to the convergence of algorithm in the early stage of iteration and increasing the diversity of population in the late stage of iteration. Experimental results show that the proposed algorithm can be an efficient alternative for solving integer programming problems.

The reactive power optimization problem has a significant influence on secure and economic operation of power systems. Reactive power optimization of power systems is a kind of mixed nonlinear integer programming problem and can reduce network loss by changing transformer taps, adjusting generator terminal voltage and connecting shunt capacitors. This paper proposes global differential evolution (GDE) algorithm which can improve the convergence speed and avoid local optimum. GDE is utilized to solve the reactive power optimization problems.Experimental results show that GDE algorithm is an effective algorithm to solve reactive power optimization problem and its optimization result is better than other algorithms.

An effective global harmony search algorithm (EGHS) is proposed to solve integer programming problems. The EGHS designs a novel location updating equation, which enables the improvised solution to move to the global best solution rapidly in each iteration. Random selection with a low probability is carried out for the improvised solution after updating location, for it can prevent the EGHS from being trapped into the local optimum. The results show that the EGHS can be an efficient alternative for solving integer programming problems.

Chemical equation balancing is an important issue in the field of chemistry, and it has drawn many researchers' attention over the last few decades. Essentially, chemical equation balancing can be classified as integer programming problem with equality constraints. In this paper, we use a recently proposed algorithm - the novel global harmony search algorithm (NGHS) to solve this problem. The NGHS algorithm is an improved version of harmony search algorithm (HS), and it includes two important operations: position updating and genetic mutation with a low probability. The former can enhance the convergence of the NGHS, and the latter can effectively prevent the NGHS from trapping into the local optimum. Based on a large number of experiments, the NGHS has demonstrated high efficiency on solving chemical equation balancing. The results show that the NGHS can be an efficient alternative for solving chemical equation balancing.