An Improved Particle Swarm Optimization for Traveling Salesman Problem

In order to improve the efficiency and reduce energy consumption of unmanned sailing boats for water quality inspection and sampling, particle swarm optimization was used for global path planning. The traditional particle swarm optimization algorithm has the problem of premature convergence because it is easy to fall into the local optimal solution. To solve this problem, an improved particle swarm optimization algorithm is proposed. Based on the traditional particle swarm optimization algorithm, the crossover and mutation operations in genetic algorithm are introduced. Firstly, the particle swarm was initialized and the fitness of the particle was calculated, and the individual optimal value and local optimal value were updated. Then crossover and mutation operations are introduced to update the particle velocity and position according to the results. Finally, the convergence of the algorithm is judged according to the decision criteria. The simulation results show that compared with the traditional particle swarm optimization algorithm, this algorithm can effectively avoid the algorithm falling into the local optimal solution, and greatly shorten the overall path length and reduce path planning time.

The existing algorithm of generating test paper has the problem of low efficiency and slow convergence rate, etc. Improved particle swarm algorithm for test paper auto-generating is proposed on the basic of the particle swarm optimization algorithm and improved genetic algorithm. The algorithm uses greedy algorithm to optimize the initial population. The crossover and mutation operator of genetic algorithm are used to avoid the local convergence of population during the process of iteration. Experimental results show that the improved particle swarm optimization algorithm can applied to auto-generating test paper, which has faster speed and higher success rate.

Ant colony optimization algorithm with mutation mechanism and its applications

Ultra-high performance concrete has excellent mechanical properties such as ultra-high strength and high durability, and has a broad application prospect in the field of bridge engineering. To make full use of the superior mechanical properties of UHPC and reduce the cost of the bridge, the particle swarm optimization algorithm is used to optimize the structural design of the UHPC beam bridge; Aiming at the problem that the traditional particle swarm optimization algorithm is easy to fall into local optimum, the nonlinear adaptive weight update method is used to improve the particle swarm optimization algorithm. Based on the above-mentioned improved particle swarm optimization algorithm, the optimal design method of ordinary reinforced UHPC beams and prestressed UHPC beams with commonly used highway spans is studied. The reliability of the optimized structural limit state is analyzed by Monte Carlo (MC) importance sampling method. The results show that compared with the traditional particle swarm optimization algorithm, the improved particle swarm optimization algorithm has higher convergence speed and convergence accuracy. The optimal height-span ratio of ordinary reinforced UHPC beams decreases with the increase of the span, and the construction cost gradually increases; The optimal height-span ratio of the prestressed beam decreases first and then increases with the increase of the span, and the construction cost gradually increases. The calculation results of load capacity reliability indexes of optimization results are all higher than the target reliability indexes of similar components stipulated in China’s “Uniform Standard for Structural Reliability Design of Highway Engineering”.

In the area of cloud computing load balancing, the Particle Swarm Optimization (PSO) algorithm is neoteric and now praised highly, but recently a more neoteric algorithm which deploys the classifier into load balancing is presented. Besides, an algorithm called red-black tree which is aiming at improving the efficiency of resource dispatching is also praised. But the 3 algorithms all have different disadvantages which cannot be ignored. For example, the dispatch efficiency of PSO algorithm is not satisfying; although classifier and red-black tree algorithm improve the efficiency of dispatching tasks, the performance in load balancing is not that good, as a result the improved PSO algorithm is presented. Some researches are designed to get the advantages of new algorithm. First of all, the time complexity and performance for each algorithm in theory are computed; and then actual data which are generated in experiments are given to demonstrate the performance. And from the experiment result, it can be found that for the speed of algorithm itself PSO is the lowest, and the improved PSO solve this problem in some degree; improved PSO algorithm has the best performance in task solving and PSO is the second one, the red-black and Naive Bayes algorithm are much slower; PSO and improved PSO algorithm perform well in load balancing, while the other two algorithms do not do well.

System delay caused by mechanical transmission, control calculation and data communication are the main factor affecting the man-machine collaborative control of lower extremity exoskeleton. Improved Particle Swarm Optimization Algorithm (IPSO) was proposed to optimize BPNN (Back Propagation Neural Network) to predict the future joint angle of human lower limb. The 3d motion capture system was used to collect the Angle data of human lower limb joints, and time span was added to reconstruct the time series, which was taken as the input of the model. Compared to PSO (Particle Swarm Optimization), IPSO added a three-route competitive optimization trajectory, the training feedback of BPNN and mutation operation, which accelerated the convergence of the algorithm and avoided local optimization. Besides, we established a prediction evaluation criterion with prediction duration, iteration efficiency, Root Mean Square Error (RMSE) and Determination Coefficient (DC) as the core to analyze the prediction results of BPNN, PSO-BPNN (Support Back Propagation Neural Network by Particle Swarm Optimization) and IPSO-BPNN (Support Back Propagation Neural Network by Improved Particle Swarm Optimization). The results show that the average RMSE of IPSO-BPNN is less than 0.75 and DC is more than 98%. IPSO-BPNN can make more accurate prediction of human lower limb joint angle, which is beneficial to improve the man-machine coordination performance of exoskeleton.

in architectural decoration process, pressure-bearing capacity test is the foundation of design, and is very important. To this end, a pressure-bearing capacity test method in architectural decoration design is proposed based on improved genetic algorithm. The selection, crossover and mutation operators in genetic algorithm are improved respectively. Using its fast convergence characteristics eliminate the pressure movement in the calculation process. The abnormal area of pressure-bearing existed in buildings which can ensure to be tested is added, to obtain accurate distribution information of the abnormal area of pressure-bearing. Simulation results show that the improved genetic algorithm has good convergence, can accurately test the pressure-bearing capacity in architectural decoration.

Aiming at the problem that traditional BP algorithm is prone to fall into local optimum when carrying out thunderstorm disaster prediction, a thunderstorm disaster prediction method based on BP neural network optimized by enhanced GWO algorithm is proposed in this paper. Firstly, the global search capability of GWO is enhanced by introducing clone mutation operation in genetic algorithm and position update idea in particle swarm optimization, and the convergence speed of the algorithm is improved. Then, the BP neural network weight and threshold optimized by the enhanced GWO algorithm are used to build the network model and predict the occurrence of thunderstorm disasters. Simulation results show that compared with the original BP algorithm, GWO-BP algorithm and PSO-BP algorithm, the improved IPSGWO-BP algorithm improves the accuracy of thunderstorm disaster prediction by 13.33%, 12.50% and 8.33%, respectively. Meanwhile, the null alarm rate is lower, the optimization ability is stronger, and the convergence speed is faster.

Particle swarm optimization (PSO) has been widely used in the fields of function optimization and neural network training because it's simple, easy to implement, has less parameters. The selection of algorithm parameters is very important to the speed optimization and results of the algorithm optimization. PSO is easy to fall into the local optimal value and when the number of particles is less, the optimization accuracy is greatly reduced. In addition, local search capability and global search capability are mutually restricted. According to above disadvantages Improved Particle Swarm Optimization based on the Gauss function and the sine function is proposed. By optimizing the inertia weight and speed coefficient of the PSO algorithm, the optimization speed and precision of the algorithm are improved. And improved algorithm is applied to the identification of the system, and the identification results are compared with the existing BPSO and the WPSO. Finally, it is concluded that the improved particle swarm optimization algorithm can get better results than other PSO.

Although there are many methods or models widely applied to evaluate water resources carrying capacity, the evaluation result is qualitative not quantitative. In order to quantificationally evaluate groundwater carrying capacity in irrigation district, multi-objective evaluation model of groundwater carrying capacity was established, which includes four objectives, i.e., GDP, grain yield, population and COD emissions. The multi-objectives model can factually describe groundwater carrying capacity for social economy subsystem and ecological environment subsystem in irrigation district. The improved Particle Swarm Optimization (PSO) algorithm was built and adopted to solving the groundwater carrying capacity multi-objective model. In the improve PSO algorithm, linear inertia weight and chaos variation operator are employed to improve basic algorithm global searching capacity. The model was applied to quantificationally evaluate groundwater carrying capacity of People's Victory Canal irrigation district in current year and in 2010 level year.

This paper deals with the optimal path planning problem for mobile robot which are drove in obstacle environment. Specially, we aim at solving the deadlock problem using grid network and improved particle swarm optimization algorithm. The proposed method is different from traditional particle swarm optimization method, which generally has high-computational complexity and local deadlock. Instead, we utilize the integrated grid network and improved particle swarm optimization algorithm. By the grid network, the long path in the whole workspace with obstacles is divided into multi-segment continuous short paths. The improved particle swarm optimization is used in the short paths by the robot. Then the grids are prioritized and according to the grids priority in the short path, an integrated algorithm is proposed. By applying the proposed algorithm, the mobile robot move to the target along the optimal path without obstacle collision and deadlock. Finally, some experiments are provided to demonstrate the effectiveness of our proposed algorithm.

It is of great significance to study how to use intelligent algorithm to optimize the scheduling of microgrid, so as to improve the operation efficiency of microgrid. In this paper, particle swarm optimization(PSO) algorithm is improved by nonlinearly decreasing inertia weight and nonlinearly dynamic adjusting learning factors. Compared with PSO, the global search ability of the improved particle swarm optimization(IPSO) algorithm is improved. IPSO is used to optimize the scheduling of the microgrid grid connection model. The example results show that nonlinearly decreasing inertia weight and nonlinearly dynamic adjusting learning factors can obviously improve PSO. IPSO has faster convergence and lower comprehensive cost of microgrid scheduling. This paper provides an effective method for the day ahead economic scheduling of microgrid.

Optimisation of fixture layout is critical to reduce geometric and form error of the workpiece during the machining process. In this paper the optimal placement of fixture elements (locator and clamp locations) under dynamic conditions is investigated using evolutionary techniques. The application of the newly developed particle swarm optimisation (PSO) algorithm and widely used genetic algorithm (GA) is presented to minimise elastic deformation of the workpiece considering its dynamic response. To improve the performances of GA and PSO, an improved GA (IGA) obtained by basic GA (GA) with sharing and adaptive mutation and an improved PSO (IPSO) obtained by basic PSO (PSO) incorporated into adaptive mutation are developed. ANSYS parametric design language (APDL) of finite element analysis is employed to compute the objective function for a given fixture layout. Three layout optimisation cases derived from the high speed slot milling case are used to test the effectiveness of the GA, IGA, PSO and IPSO based approaches. The comparisons of computational results show that IPSO seems superior to GA, IGA and PSO approaches with respect to the trade-off between global optimisation capability and convergence speed for the presented type problems.

The optimal power flow (OPF) problem was introduced by Carpentier in 1962 as a network constrained economic dispatch problem. Since then, it has been intensively studied and widely used in power system operation and planning. In the past few decades, many stochastic optimization methods such as Genetic Algorithm (GA), Evolutionary Programming (EP), and Particle Swarm Optimization (PSO) have been applied to solve the OPF problem. In particular, PSO is a newly proposed population based stochastic optimization algorithm. The main idea behind it is based on the food-searching behavior of birds and fish. Compared with other stochastic optimization methods, PSO has comparable or even superior search performance for some hard optimization problems in real power systems. Nowadays, some modifications such as breeding and selection operators are considered to make the PSO superior and robust. In this paper, we propose the Modified PSO (MPSO), in which the mutation operator of GA is incorporated into the conventional PSO to improve the search performance. To verify the optimal solution searching ability, the proposed approach has been evaluated on an IEEE 30-bus test system. The results showed that performance of the proposed approach is better than that of the standard PSO.

This research has concentrated on topologies of DC- DC converter for Power Factor Correction for DC power supplies. The foremost objective of this effort is to improve a Bridge Less Zeta Power Factor Correction (PFC) converter implement with fractional order PID (FOPID) controller. It can be adjusted using the Improved Particle Swarm Optimization (PSO) algorithm is presented that will enhance the supply side Power Quality (PQ) and yield regulated DC voltage at the output side. To establish the FOPID controllers, an updated PSO technique is employed and position of the particle is ensured within the designated hunt areas with momentum factor. The control system based on the fractional PID algorithm outperforms the particle swarm optimization approach and the genetic algorithm. The right controller design for the converter ensures excellent performance, which is tested using simulation data. The recommended Bridge Less Zeta converter is evaluated for DC load voltage regulation under various load power and supply voltage fluctuations.