Optimization of Fairhurst-Cook Model for 2-D Wing Cracks Using Ant Colony Optimization (ACO), Particle Swarm Intelligence (PSO), and Genetic Algorithm (GA)

The common failure mechanism for brittle rocks is known to be axial splitting which happens parallel to the direction of maximum compression. One of the mechanisms proposed for modelling of axial splitting is the sliding crack or so called, “wing crack” model. Fairhurst-Cook model explains this specific type of failure which starts by a pre-crack and finally breaks the rock by propagating 2-D cracks under uniaxial compression. In this paper, optimization of this model has been considered and the process has been done by a complete sensitivity analysis on the main parameters of the model and excluding the trends of their changes and also their limits and “peak points”. Later on this paper, three artificial intelligence algorithms including Particle Swarm Intelligence (PSO), Ant Colony Optimization (ACO) and genetic algorithm (GA) has been used and compared in order to achieve optimized sets of parameters resulting in near-maximum or near-minimum amounts of wedging forces creating a wing crack.

A Scheme Library-Based Ant Colony Optimization with 2-Opt Local Search for Dynamic Traveling Salesman Problem

The dynamic traveling salesman problem(DTSP)is significant in logistics distribution in real-world applications in smart cities,but it is uncertain and difficult to solve.This paper proposes a scheme library-based ant colony optimization(ACO)with a two-optimization(2-opt)strategy to solve the DTSP efficiently.The work is novel and contributes to three aspects:problemmodel,optimization framework,and algorithmdesign.Firstly,in the problem model,traditional DTSP models often consider the change of travel distance between two nodes over time,while this paper focuses on a special DTSP model in that the node locations change dynamically over time.Secondly,in the optimization framework,the ACO algorithm is carried out in an offline optimization and online application framework to efficiently reuse the historical information to help fast respond to the dynamic environment.The framework of offline optimization and online application is proposed due to the fact that the environmental change inDTSPis caused by the change of node location,and therefore the newenvironment is somehowsimilar to certain previous environments.This way,in the offline optimization,the solutions for possible environmental changes are optimized in advance,and are stored in a mode scheme library.In the online application,when an environmental change is detected,the candidate solutions stored in the mode scheme library are reused via ACO to improve search efficiency and reduce computational complexity.Thirdly,in the algorithm design,the ACO cooperates with the 2-opt strategy to enhance search efficiency.To evaluate the performance of ACO with 2-opt,we design two challenging DTSP cases with up to 200 and 1379 nodes and compare them with other ACO and genetic algorithms.The experimental results show that ACO with 2-opt can solve the DTSPs effectively.

Route Search Method for Railway Replacement Buses Adopting Ant Colony Optimization

In recent years, Japan, and especially rural areas have faced the growing problems of debt-ridden local railway lines along with the population decline and aging population. Therefore, it is best to consider the discontinuation of local railway lines and introduce replacement buses to secure the transportation methods of the local people especially in rural areas. Based on the above background, targeting local railway lines that may be discontinued in the near future, appropriate bus stops when provided with potential bus stops were selected, the present study proposed a method that introduces routes for railway replacement buses adopting ant colony optimization (ACO). The improved ACO was designed and developed based on the requirements set concerning the route length, number of turns, road width, accessibility of railway lines and zones without bus stops as well as the constraint conditions concerning the route length, number of turns and zones without bus stops. Original road network data were generated and processed adopting a geographic information systems (GIS), and these are used to search for the optimal route for railway replacement buses adopting the improved ACO concerning the 8 zones on the target railway line (JR Kakogawa line). By comparing the improved ACO with Dijkstra’s algorithm, its relevance was verified and areas needing further improvements were revealed.

An effective multi-level algorithm based on ant colony optimization for graph bipartitioning

Partitioning is a fundamental problem with applications to many areas including data mining, parellel processing and Very-large-scale integration （VLSI） design. An effective multi-level algorithm for bisecting graph is proposed. During its coarsening phase, an improved matching approach based on the global information of the graph core is developed with its guidance function. During the refinement phase, the vertex gain is exploited as ant＇s heuristic information and a positive feedback method based on pheromone trails is used to find the global approximate bipartitioning. It is implemented with American National Standards Institute （ANSI） C and compared to MeTiS. The experimental evaluation shows that it performs well and produces encouraging solutions on 18 different graphs benchmarks.

An adaptive ant colony system algorithm for continuous-space optimization problems

Ant colony algorithms comprise a novel category of evolutionary computation methods for optimization problems, especially for sequencing-type combinatorial optimization problems. An adaptive ant colony algorithm is proposed in this paper to tackle continuous-space optimization problems, using a new objective-function-based heuristic pheromone assignment approach for pheromone update to filtrate solution candidates.Global optimal solutions can be reached more rapidly by self-adjusting the path searching behaviors of the ants according to objective values. The performance of the proposed algorithm is compared with a basic ant colony algorithm and a Square Quadratic Programming approach in solving two benchmark problems with multiple extremes. The results indicated that the efficiency and reliability of the proposed algorithm were greatly improved.

Electro-Hydraulic Servo System Identification of Continuous Rotary Motor Based on the Integration Algorithm of Genetic Algorithm and Ant Colony Optimization

In order to increase the robust performance of electro-hydraulic servo system, the system transfer function was identified by the intergration algorithm of genetic algorithm and ant colony optimization(GA-ACO), which was based on standard genetic algorithm and combined with positive feedback mechanism of ant colony algorithm. This method can obtain the precise mathematic model of continuous rotary motor which determines the order of servo system. Firstly, by constructing an appropriate fitness function, the problem of system parameters identification is converted into the problem of system parameter optimization. Secondly, in the given upper and lower bounds a set of optimal parameters are selected to meet the best approximation of the actual system. And the result shows that the identification output can trace the sampling output of actual system, and the error is very small. In addition, another set of experimental data are used to test the identification result. The result shows that the identification parameters can approach the actual system. The experimental results verify the feasibility of this method. And it is fit for the parameter identification of general complex system using the integration algorithm of GA-ACO.

Solving algorithm for TA optimization model based on ACO-SA

An ant colony optimization （ACO）-simulated annealing （SA）-based algorithm is developed for the target assignment problem （TAP） in the air defense （AD） command and control （C2） system of surface to air missile （SAM） tactical unit. The accomplishment process of target assignment （TA） task is analyzed. A firing advantage degree （FAD） concept of fire unit （FU） intercepting targets is put forward and its evaluation model is established by using a linear weighted synthetic method. A TA optimization model is presented and its solving algorithms are designed respectively based on ACO and SA. A hybrid optimization strategy is presented and developed synthesizing the merits of ACO and SA. The simulation examples show that the model and algorithms can meet the solving requirement of TAP in AD combat.

Efficiency improvement of ant colony optimization in solving the moderate LTSP

In solving small- to medium-scale travelling salesman problems （TSPs） of both symmetric and asymmetric types, the traditional ant colony optimization （ACO） algorithm could work well, providing high accuracy and satisfactory efficiency. However, when the scale of the TSP increases, ACO, a heuristic algorithm, is greatly challenged with respect to accuracy and efficiency. A novel pheromone-trail updating strategy that moderately reduces the iteration time required in real optimization problem-solving is proposed. In comparison with the traditional strategy of the ACO in several experiments, the proposed strategy shows advantages in performance. Therefore, this strategy of pheromone-trail updating is proposed as a valuable approach that reduces the time-complexity and increases its efficiency with less iteration time in real optimization applications. Moreover, this strategy is especially applicable in solving the moderate large-scale TSPs based on ACO.

Traveling Salesman Problem Using an Enhanced Hybrid Swarm Optimization Algorithm

The traveling salesman problem( TSP) is a well-known combinatorial optimization problem as well as an NP-complete problem. A dynamic multi-swarm particle swarm optimization and ant colony optimization( DMPSO-ACO) was presented for TSP.The DMPSO-ACO combined the exploration capabilities of the dynamic multi-swarm particle swarm optimizer( DMPSO) and the stochastic exploitation of the ant colony optimization( ACO) for solving the traveling salesman problem. In the proposed hybrid algorithm,firstly,the dynamic swarms,rapidity of the PSO was used to obtain a series of sub-optimal solutions through certain iterative times for adjusting the initial allocation of pheromone in ACO. Secondly,the positive feedback and high accuracy of the ACO were employed to solving whole problem. Finally,to verify the effectiveness and efficiency of the proposed hybrid algorithm,various scale benchmark problems were tested to demonstrate the potential of the proposed DMPSO-ACO algorithm. The results show that DMPSO-ACO is better in the search precision,convergence property and has strong ability to escape from the local sub-optima when compared with several other peer algorithms.

Research of Rural Power Network Reactive Power Optimization Based on Improved ACOA

In view of the serious reactive power loss in the rural network, improved ant colony optimization algorithm （ACOA） was used to optimize the reactive power compensation for the rural distribution system. In this study, the traditional ACOA was improved in two aspects： one was the local search strategy, and the other was pheromone mutation and re-initialization strategies. The reactive power optimization for a county＇s distribution network showed that the improved ACOA was practicable.

Application of GA, PSO, and ACO Algorithms to Path Planning of Autonomous Underwater Vehicles

在这份报纸，一在水下车辆与运动的六个维的非线性的方程被建模，在自由的所有度由 DC 马达控制了。在精力充沛的环境为的在最佳附近的轨道在水下车辆用一个非线性的最佳的控制问题(NOCP ) 的一个数字答案被计算。一个费用函数，应该被最小化，被定义的一个精力性能索引。产生问题是一个二点的边界价值问题(TPBVP ) 。一个基因算法(GA ) ，粒子群优化(PSO ) ，和蚂蚁殖民地优化(ACO ) 算法被使用解决产生 TPBVP。把一个 Euler-Lagrange 方程用于 NOCP，一个 conjugate 坡度惩罚方法也被采用解决 TPBVP。精力充沛的环境的问题，包含一些精力采购原料，被讨论。一些在最佳附近的路径用 GA， PSO，和 ACO 算法被发现。最后，在精力充沛的环境的碰撞回避的问题也被考虑。

基于多精度规划窗口的无人机航迹规划方法研究

航迹规划是无人机(unmanned aerial vehicle,UAV)任务规划系统的核心部分之一,其主要任务是结合战场环境等约束条件,寻找一条安全系数高、满足任务需求且飞行代价小的UAV最优飞行航迹。基于现有蚁群优化(ant colony optimization,ACO)算法,在其并行能力基础上提出一种多精度规划窗口方法。该方法在初始航迹基础上,进一步针对局部飞行环境特点,自动配置局部规划窗口、规划精度和规划参数,并行地开展多精度窗口航迹调整,可在较短时间内优化出一条适应战场环境的飞行航迹。仿真分析表明,不同战场环境下所需的算法参数配置、规划精度各有不同,通过多精度规划窗口的优化与调整,最终飞行航迹可适应不同战场环境,且具备较好的规划效率与精度。

一种基于ACO的K-medoids聚类算法

K-medoids算法作为聚类算法的一种,不易受极端数据的影响,适应性广泛,但是K-medoids聚类算法的精确度不稳定,平均准确率较低,用于实际的聚类分析时效果较差。ACO是一种仿生优化算法,其具有很强的健壮性,容易与其他方法相结合,求解效率高等特点。在K-medoids聚类算法的基础上,借鉴ACO算法的优点,提出了一种新的聚类算法,它提高了聚类的准确率,算法的稳定性也比较高。通过仿真实验,验证了算法的可行性和先进性。

Optimization of Linear Consecutive-k-Out-of-n Systems with Birnbaum Importance Based Ant Colony Optimization Algorithm

The linear consecutive-k-out-of-n:failure(good)(Lin/Con/k/n:F(G))system consists of n interchangeable components that have different reliabilities.These components are arranged in a line path and different component assignments change the system reliability.The optimization of Lin/Con/k/n:F(G)system is to find an optimal component assignment to maximize the system reliability.As the number of components increases,the computation time for this problem increases considerably.In this paper,we propose a Birnbaum importance-based ant colony optimization(BIACO)algorithm to obtain quasi optimal assignments for such problems.We compare its performance using the Birnbaum importance based two-stage approach(BITA)and Birnbaum importancebased genetic local search(BIGLS)algorithm from previous researches.The experimental results show that the BIACO algorithm has a good performance in the optimization of Lin/Con/k/n:F(G)system.

基于ACO-LSSVM的网络流量预测

为了提高了网络流量的预测精度,提出一种蚁群算法(ACO)优化最小二乘支持向量机(LSSVM)参数的网络流量预测算法(ACO-LSSVM)。将LSSVM算法参数作为蚂蚁的位置向量,采用动态随机抽取的方法来确定目标个体引导蚁群进行全局搜索,并在最优蚂蚁邻域内进行小步长局部搜索,找到算法的最优参数,建立了基于ACO-LSSVM的网络流量预测模型。仿真结果表明,相对其他网络流量预测算法,ACO-LSSVM算法提高了网络流量预测精度,更能准确地描述网络流量变化规律。

基于多蚁群的并行ACO算法

通过改变蚁群优化(ACO)算法行为,提出一种新的ACO并行化策略——并行多蚁群ACO算法。针对蚁群算法存在停滞现象的缺点,改进选择策略,实现具有自适应并行机制的选择和搜索策略,以加强其全局搜索能力。并行处理采用数据并行的手段,能减少处理器间的通信时间并获得更好的解。以对称TSP测试集为对象进行比较实验,结果表明,该算法相对于串行算法及现有的并行算法具有一定的优势。

海上油田群水域应急救援船舶路径规划方法研究

文中提出了基于Dijkstra-ACO算法的海上油田群水域应急救援船舶路径规划方法.根据油田群水域的环境特征,运用Maklink图论算法构建救援船舶路径规划的二维空间模型,并结合Dijkstra算法与ACO算法提出应急救援船舶的路径规划算法,以山东东营油田群水域为例进行模型验证.结果表明:基于Dijkstra-ACO的应急救援船舶路径规划方法优于传统路径规划方法.

一种基于DLS和ACO的平台资源规划方法

平台资源规划方法是作战任务规划的重要组成部分,为作战提供资源分配方案。描述了作战任务、平台以及它们之间的关系,建立了以最小化全部任务完成的截止时间和最大化平台资源的利用率为目标的数学模型。设计了用于求解此模型的动态列表规划(Dynamic List Scheduling,DLS)与蚁群算法(Ant Colony Optimization Algorithm,ACO)相结合的算法,其描述了任务选择方法、ACO的二进制编码方案及候选解构造策略,设计了不可行候选解的修正策略和信息素更新方法,构造了包含任务选择平台的时间优先系数、平台功能能力优先系数和后续任务对平台需求程度3个因素的适应度函数。针对作战想定进行了仿真计算,结果表明,基于DLS和ACO的平台资源规划具有良好的规划效果,相比于他人算法,其具有更少的全部任务完成截止时间和更高的平台资源利用率。

基于ACO-BP神经网络的土石坝位移监测模型研究

建立安全监测网络模型来分析和预测大坝变形位移信息,对保障大坝安全稳定服役意义重大。针对大坝安全监测BP神经网络模型运算复杂、收敛速度慢、易陷于局部最优、不能准确反映和预测大坝运行状况的问题,引入蚁群算法(ACO)全局搜索功能搜寻BP神经网络参数最优解,并通过样本数据训练BP网络获得大坝变形位移预测值。工程实例应用表明:ACO-BP网络模型在参数优化方面较BP网络更易于收敛,误差较小、预测性能良好,可为大坝变形位移监测和安全预报提供一种新的非线性建模仿真分析方法。

基于改进Ant-miner算法的分类规则挖掘

为提高基于传统Ant-miner算法分类规则的预测准确性,提出一种基于改进Ant-miner的分类规则挖掘算法。利用样例在总样本中的密度及比例构造启发式函数,以避免在多个具有相同概率的选择条件下造成算法偏见。对剪枝规则按变异系数进行单点变异,由此扩大规则的搜索空间,提高规则的预测准确度。在Ant-miner算法的信息素更新公式中加入挥发系数,使其更接近现实蚂蚁的觅食行为,防止算法过早收敛。基于UCI标准数据的实验结果表明,该算法相比传统Ant-miner算法具有更高的预测准确度。