Evolutionary fuzzy particle swarm optimization vector quantization learning scheme in image compression

This article develops an evolutional fuzzy particle swarm optimization (FPSO) learning algorithm to self extract the near optimum codebook of vector quantization (VQ) for carrying on image compression. The fuzzy particle swarm optimization vector quantization (FPSOVQ) learning schemes, combined advantages of the adaptive fuzzy inference method (FIM), the simple VQ concept and the efficient particle swarm optimization (PSO), are considered at the same time to automatically create near optimum codebook to achieve the application of image compression. The FIM is known as a soft decision to measure the relational grade for a given sequence. In our research, the FIM is applied to determine the similar grade between the codebook and the original image patterns. In spite of popular usage of Linde–Buzo–Grey (LBG) algorithm, the powerful evolutional PSO learning algorithm is taken to optimize the fuzzy inference system, which is used to extract appropriate codebooks for compressing several input testing grey-level images. The proposed FPSOVQ learning scheme compared with LBG based VQ learning method is presented to demonstrate its great result in several real image compression examples.     

HEURISTIC PARTICLE SWARM OPTIMIZATION LEARNING-BASED IMAGE COMPRESSION SYSTEM

Traditional LBG algorithm is a pure iterative optimization procedure to achieve the vector quantization (VQ) codebook, where an initial codebook is continually refined at every iteration to reduce the distortion between code-vectors and a given training data set. However, such interactive type learning algorithms will easily direct final results converging toward the local optimization while the high quality of the initial codebook is not available. In this article, an efficient heuristic-based learning method, called novel particle swarm optimization (NPSO), is proposed to design the proper codebook of VQ scheme that can develop the image compression system. To improve the performance of the basic PSO, the centroid updating machine applies the one step-size gradient descent learning step in the heuristic learning procedure. Additionally, the presented NPSO with advantages of the centroid updating machine is proposed to quickly achieve the near-optimal reconstructive image. For demonstrating the proposed NPSO learning scheme, the image with several horizontal grey bars is first applied to present the efficiency of the NPSO learning mechanism. LBG and NPSO learning methods are also applied to test the reconstructing performance in several type images “Lena,” “Airplane,” “Cameraman”, and “peppers.” In our experiments, the NPSO learning algorithm provides the higher performance than conventional LBG methods in the application of building image compression system.     

人工蜂群算法改进DHMM的语音识别方法

针对离散隐马尔可夫(Discrete Hidden Markov Model,DHMM)语音识别系统中LBG算法对初始码书的依赖性和易陷入局部最优解的问题,采用人工蜂群(Artificial Bee Colony,ABC)算法对语音特征参数进行矢量量化,从而得到最优码书,提出了ABC改进DHMM的孤立词语音识别方法。先提取语音信号的特征参数,然后用ABC算法中每个食物源表示一个码书,以人工蜂群进化的方式对初始码书进行迭代而获得最优码书,最后把最优码书的码矢标号代入DHMM模型进行训练和识别。实验结果表明,ABC改进的DHMM语音识别方法与传统的LBG及粒子群优化初始码书的LBG的DHMM语音识别方法相比具有较高的识别率和较好的鲁棒性。     

Multiple sequence alignment using the Hidden Markov Model trained by an improved quantum-behaved particle swarm optimization

Multiple sequence alignment (MSA) is an NP-complete and important problem in bioinformatics. For MSA, Hidden Markov Models (HMMs) are known to be powerful tools. However, the training of HMMs is computationally hard so that metaheuristic methods such as simulated annealing (SA), evolutionary algorithms (EAs) and particle swarm optimization (PSO), have been employed to tackle the training problem. In this paper, quantum-behaved particle swarm optimization (QPSO), a variant of PSO, is analyzed mathematically firstly, and then an improved version is proposed to train the HMMs for MSA. The proposed method, called diversity-maintained QPSO (DMQPO), is based on the analysis of QPSO and integrates a diversity control strategy into QPSO to enhance the global search ability of the particle swarm. To evaluate the performance of the proposed method, we use DMQPSO, QPSO and other algorithms to train the HMMs for MSA on three benchmark datasets. The experiment results show that the HMMs trained with DMQPSO and QPSO yield better alignments for the benchmark datasets than other most commonly used HMM training methods such as Baum–Welch and PSO.     

基于量子粒子群算法的复杂函数参数估计

数理统计中在处理回归的问题时,常用的传统参数估计方法存在着一些严重不足之处.为解决此问题,提出了将基于量子行为的微粒群优化(QPSO)算法应用于复杂函数的参数估计中.通过仿真实验,表明了该算法不仅可以准确地估计出复杂函数的参数,并且具有计算简便、收敛速度快等特点.通过与传统微粒群(PSO)算法的比较,证明了QPSO算法的优越性.     

A two-stage quantum-behaved particle swarm optimization with skipping search rule and weight to solve continuous optimization problem

Quantum-behaved particle swarm optimization (QPSO) is a recently developed heuristic method by particle swarm optimization (PSO) algorithm based on quantum mechanics, which outperforms the search ability of original PSO. But as many other PSOs, it is easy to fall into the local optima for the complex optimization problems. Therefore, we propose a two-stage quantum-behaved particle swarm optimization with a skipping search rule and a mean attractor with weight. The first stage uses quantum mechanism, and the second stage uses the particle swarm evolution method. It is shown that the improved QPSO has better performance, because of discarding the worst particles and enhancing the diversity of the population. The proposed algorithm (called ‘TSQPSO’) is tested on several benchmark functions and some real-world optimization problems and then compared with the PSO, SFLA, RQPSO and WQPSO and many other heuristic algorithms. The experiment results show that our algorithm has better performance than others.     

An improved cooperative quantum-behaved particle swarm optimization

Particle swarm optimization (PSO) is a population-based stochastic optimization. Its parameters are easy to control, and it operates easily. But, the particle swarm optimization is a local convergence algorithm. Quantum-behaved particle swarm optimization (QPSO) overcomes this shortcoming, and outperforms original PSO. Based on classical QPSO, cooperative quantum-behaved particle swarm optimization (CQPSO) is present. This CQPSO, a particle firstly obtaining several individuals using Monte Carlo method and these individuals cooperate between them. In the experiments, five benchmark functions and six composition functions are used to test the performance of CQPSO. The results show that CQPSO performs much better than the other improved QPSO in terms of the quality of solution and computational cost.     

QoS multicast routing using a quantum-behaved particle swarm optimization algorithm

QoS multicast routing in networks is a very important research issue in networks and distributed systems. It is also a challenging and hard problem for high-performance networks of the next generation. Due to its NP-completeness, many heuristic methods have been employed to solve the problem. This paper proposes the modified quantum-behaved particle swarm optimization (QPSO) method for QoS multicast routing. In the proposed method, QoS multicast routing is converted into an integer programming problem with QoS constraints and is solved by the QPSO algorithm combined with loop deletion operation. The QPSO-based routing method, along with the routing algorithms based on particle swarm optimization (PSO) and genetic algorithm (GA), is tested on randomly generated network topologies for the purpose of performance evaluation. The simulation results show the efficiency of the proposed method on QoS the routing problem and its superiority to the methods based on PSO and GA.     

QPSO算法优化的非线性观测器设计方法研究

具有量子行为的粒子群优化算法(Quantum-behavedParticleSwarmOptimization,简称QPSO)是继粒子群优化算法(ParticleSwarmOptimization,简称PSO)后,最新提出的一种新型、高效的进化算法。论文在研究基于PSO算法的非线性观测器基础上,提出了一种基于QPSO算法的非线性观测设计方法。以vanderPol系统为例进行了仿真实验,其基本思想是将非线性连续时间系统的状态估计问题转换为非线性函数的在线优化问题,然后利用PSO或QPSO算法获得系统状态的最优估计。仿真结果显示了基于QPSO算法的非观测器比基于PSO算法的非线性观测器的性能更优越。     

QPSO算法与PSO算法求解二维热传导反问题

热传导反问题在国内研究起步较晚,研究方法有很多,但通常方法很难较好地接近全局最优.在介绍经典的微粒群优化算法(PSO)的基础上,研究基于量子行为的微粒群优化算法(QPSO)的二维热传导参数优化方法,具体介绍依据目标函数如何利用上述的算法去寻找最优参数组合.为了提高算法的收敛性和稳定性,在具体应用中对算法进行了改进,并进行了大量实验,结果显示在解决热传导反问题优化问题中,基于QPSO算法的性能比经典PSO算法更加优越,证明QPSO在热传导领域具有很大的实际应用价值.     

Quantum-behaved particle swarm optimization: analysis of individual particle behavior and parameter selection

Quantum-behaved particle swarm optimization (QPSO), motivated by concepts from quantum mechanics and particle swarm optimization (PSO), is a probabilistic optimization algorithm belonging to the bare-bones PSO family. Although it has been shown to perform well in finding the optimal solutions for many optimization problems, there has so far been little analysis on how it works in detail. This paper presents a comprehensive analysis of the QPSO algorithm. In the theoretical analysis, we analyze the behavior of a single particle in QPSO in terms of probability measure. Since the particle's behavior is influenced by the contraction-expansion (CE) coefficient, which is the most important parameter of the algorithm, the goal of the theoretical analysis is to find out the upper bound of the CE coefficient, within which the value of the CE coefficient selected can guarantee the convergence or boundedness of the particle's position. In the experimental analysis, the theoretical results are first validated by stochastic simulations for the particle's behavior. Then, based on the derived upper bound of the CE coefficient, we perform empirical studies on a suite of well-known benchmark functions to show how to control and select the value of the CE coefficient, in order to obtain generally good algorithmic performance in real world applications. Finally, a further performance comparison between QPSO and other variants of PSO on the benchmarks is made to show the efficiency of the QPSO algorithm with the proposed parameter control and selection methods.     

A hybrid Improved Quantum-behaved Particle Swarm Optimization–Simplex method (IQPSOS) to solve power system load flow problems

This study proposes a new approach, based on a hybrid algorithm combining of Improved Quantum-behaved Particle Swarm Optimization (IQPSO) and simplex algorithms. The Quantum-behaved Particle Swarm Optimization (QPSO) algorithm is the main optimizer of algorithm, which can give a good direction to the optimal global region and Nelder Mead Simplex method (NM) which is used as a local search to fine tune the obtained solution from QPSO. The proposed improved hybrid QPSO algorithm is tested on several benchmark functions and performed better than particle swarm optimization (PSO), QPSO and weighted QPSO (WQPSO). To assess the effectiveness and feasibility of the proposed method on real problems, it is used for solving the power system load flow problems and demonstrated by different standard and ill-conditioned test systems including IEEE 14, 30 and 57 buses test systems, and compared with the conventional Newton–Raphson (NR) method, PSO and some versions of QPSO algorithms. Furthermore, the proposed hybrid algorithm is proposed for solving load flow problems with considering the reactive limits at generation buses. Simulation results prove the robustness and better convergence of IQPSOS under normal and critical conditions, when conventional load flow methods fail.     

An evolutionary lion optimization algorithm‐based image compression technique for biomedical applications

Recently, medical image compression becomes essential to effectively handle large amounts of medical data for storage and communication purposes. Vector quantization (VQ) is a popular image compression technique, and the commonly used VQ model is Linde–Buzo–Gray (LBG) that constructs a local optimal codebook to compress images. The codebook construction was considered as an optimization problem, and a bioinspired algorithm was employed to solve it. This article proposed a VQ codebook construction approach called the L2‐LBG method utilizing the Lion optimization algorithm (LOA) and Lempel Ziv Markov chain Algorithm (LZMA). Once LOA constructed the codebook, LZMA was applied to compress the index table and further increase the compression performance of the LOA. A set of experimentation has been carried out using the benchmark medical images, and a comparative analysis was conducted with Cuckoo Search‐based LBG (CS‐LBG), Firefly‐based LBG (FF‐LBG) and JPEG2000. The compression efficiency of the presented model was validated in terms of compression ratio (CR), compression factor (CF), bit rate, and peak signal to noise ratio (PSNR). The proposed L2‐LBG method obtained a higher CR of 0.3425375 and PSNR value of 52.62459 compared to CS‐LBG, FA‐LBG, and JPEG2000 methods. The experimental values revealed that the L2‐LBG process yielded effective compression performance with a better‐quality reconstructed image.     

一种采用完全学习策略的量子行为粒子群优化算法

为了进一步提高量子行为粒子群优化（QPSO）算法的全局收敛性能,有效改善算法中存在的粒子早熟问题提出一种基于完全学习策略的改进QPSO算法（CLQPSO）.该学习策略改变了QPSO中局部吸引子的更新方式,充分利用了种群的社会信息.采用8个测试函数对算法性能进行比较分析.实验结果表明,所提出的改进算法不仅收敛速度快,而且全局收敛能力好,收敛精度优于PSO算法和QPSO算法.     

基于量子行为粒子群优化算法的定位技术研究

针对无线传感器网络(WSNs)节点定位问题,阐述了WSNs的分布迭代式定位方法研究。这种方法将每次迭代后定位的节点作为其余未知节点的参考节点.同时将基于测距定位问题看成一个多维优化问题,并提出利用具有快速收敛能力的量子行为粒子群优化(QPSO)算法进行求解。最后将仿真实验结果与粒子群优化(PSO)算法进行比较,表明QPSO算法在优化性能上优于PSO算法,有效提高了节点定位精度,证明该方法的有效性。     

基于量子行为的粒子群优化算法分类规则获取*

介绍了基本的粒子群算法,并针对基本的粒子群算法在收敛性能上的缺陷,提出将具有量子行为的粒子群优化算法应用于数据挖掘学科中的分类规则获取。对加州大学厄文分校的若干数据集模式分类规则进行提取,与其他规则提取方法相比,证明该算法提高了分类规则的正确率以及全局寻优能力。     

基于QPSO算法的单阶段投资组合优化

投资组合优化问题是NP难解问题,通常的方法很难较好地接近全局最优.在经典微粒群算法(PSO)的基础上,研究了基于量子行为的微粒群算法(QPSO)的单阶段投资组合优化方法,具体介绍了依据目标函数如何利用QPSO算法去寻找最优投资组合.在具体应用中,为了提高算法的收敛性和稳定性对算法进行了改进.利用真实历史数据进行验证,结果表明在解决单阶段投资组合优化问题时,基于QPSO算法的投资组合优化的性能比PSO算法更加优越,且QPSO算法在投资组合优化领域具有很大的实际应用价值.     

量子粒子群算法在电力系统经济调度中的应用

量子粒子群算法以粒子群算法为基础,加入了量子波动理论,具有较好的全局收敛性.通过对电力系统经济调度问题中高维数、非线性、多约束等特点进行分析,运用具有量子行为的粒子群优化算法来解决电力系统经济调度问题,经过多组算例的测试:在满足电力系统各种约束的前提下,证明了新方法有效可行,能取得较好的收敛结果和鲁棒性.     

基于QPSO方法优化求解TSP

针对粒子群优化算法PSO求解旅行商问题TSP收敛速度不够快的缺陷,提出利用量子粒子群优化算法QPSO求解TSP,在交换子和交换序概念的基础上,以Matlab语言为开发工具实现了TSP最佳路径的求解.实验表明改造QPSO算法用于优化求解14点的TSP,能够迅速得到最优解,收敛速度加快,搜索效率得到较大水平提高;QPSO方法在求解组合优化问题中将非常有效.     

矢量微粒群算法及其应用

在对微粒群优化算法PSO分析的基础上，提出了矢量微粒群优化算法VPSO。该算法通过矢量运算方法来定义微粒的运动，从而达到寻找最优解的目的。将VPSO和PSO分别用于常用测试函数的优化求解，结果表明：VPSO的优化性能明屁优于PSO。基于VPSO构造的矢量微粒群神经网络（VPSONN）在丙烯腈收率软测量建模的应用中表明：基于VPSONN的丙烯腈收率软测量模型具有较高的精度，应用前景广阔。