evolutionary computation

进化计算
  • 文章类型: Journal Article
    模块化算法框架不仅允许从未在手动选择的算法组合中进行测试的组合,但它们也提供了一种结构化的方法来评估哪些算法思想对于观察到的算法性能至关重要。在这项研究中,我们提出了一种方法来分析不同模块对整体性能的影响。我们考虑了两个广泛使用的无导数黑盒优化算法家族的模块化框架,协方差矩阵自适应进化策略(CMA-ES)和差分进化策略(DE)。更具体地说,我们使用在24个BBOB问题上获得的324个modCMA-ES和576个modDE算法变体(每个变体对应于特定的模块配置)的性能数据,在2个维度的6个不同的运行时预算。我们对这些数据的分析表明,各个模块对整体算法性能的影响差异很大。值得注意的是,在检查的模块中,CMA-ES中的精英化模块和DE中的线性种群规模减少模块对性能的影响最大。此外,我们对问题景观数据的探索性数据分析表明,无论单个模块的配置如何,最相关的景观特征保持一致,但是这些特征对回归精度的影响各不相同。此外,我们应用分类器,这些分类器利用相对于训练过的模型的特征重要性来进行性能预测和性能数据,预测CMA-ES和DE算法变体的模块化配置。结果表明,与真实配置相比,预测配置在性能上没有统计学上的显着差异,百分比取决于设置(mod-CMA从49.1%到95.5%,DE从21.7%到77.1%)。
    Modular algorithm frameworks not only allow for combinations never tested in manually selected algorithm portfolios, but they also provide a structured approach to assess which algorithmic ideas are crucial for the observed performance of algorithms. In this study, we propose a methodology for analyzing the impact of the different modules on the overall performance. We consider modular frameworks for two widely used families of derivative-free black-box optimization algorithms, the Covariance Matrix Adaptation Evolution Strategy (CMA-ES) and differential evolution (DE). More specifically, we use performance data of 324 modCMA-ES and 576 modDE algorithm variants (with each variant corresponding to a specific configuration of modules) obtained on the 24 BBOB problems for 6 different runtime budgets in 2 dimensions. Our analysis of these data reveals that the impact of individual modules on overall algorithm performance varies significantly. Notably, among the examined modules, the elitism module in CMA-ES and the linear population size reduction module in DE exhibit the most significant impact on performance. Furthermore, our exploratory data analysis of problem landscape data suggests that the most relevant landscape features remain consistent regardless of the configuration of individual modules, but the influence that these features have on regression accuracy varies. In addition, we apply classifiers that exploit feature importance with respect to the trained models for performance prediction and performance data, to predict the modular configurations of CMA-ES and DE algorithm variants. The results show that the predicted configurations do not exhibit a statistically significant difference in performance compared to the true configurations, with the percentage varying depending on the setup (from 49.1% to 95.5% for mod-CMA and 21.7% to 77.1% for DE).
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  • 文章类型: Journal Article
    在福岛第一核电站,事故中释放的辐射源沉积在各种设备和建筑结构上。在退役期间,了解辐射源的分布和环境剂量当量率对于减少工人暴露和实施详细的工作计划至关重要。在这项研究中,作者介绍了一种可视化辐射源的方法,用康普顿照相机估计它们的放射性,并得出辐射源周围的剂量率。在演示测试中,康普顿相机用于可视化由沉积在室外环境中的137Cs辐射源引起的放射性热点,并估算放射性。此外,热点周围的剂量率是根据估计的放射性计算的,这证实了计算的剂量率与使用测量仪测量的剂量率相关。这种方法很新颖,使用康普顿相机进行了一系列分析,以可视化放射性热点,估计放射性,并得出周围环境中的剂量率。
    At the Fukushima Daiichi Nuclear Power Station, radiation sources released in the accident were deposited on various equipment and building structures. During decommissioning, it is crucial to understand the distribution of radiation sources and ambient dose equivalent rates to reduce worker exposure and implement detailed work planning. In this study, the author introduces a method for visualizing radiation sources, estimates their radioactivity using a Compton camera, and derives the dose rate around the radiation sources. In the demonstration test, the Compton camera was used to visualize radioactive hotspots caused by 137Cs radiation sources deposited in the outdoor environment and estimated the radioactivity. Furthermore, the dose rate around the hotspots was calculated from the estimated radioactivity, which confirmed that the calculated dose rate correlated with the dose rate measured using a survey meter. This approach is novel, where a series of analyses were conducted using the Compton camera to visualize radioactive hotspots, estimate the radioactivity, and derive the dose rate in the surrounding environment.
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  • 文章类型: Journal Article
    基因调控网络是生物体中的相互作用网络,负责确定蛋白质和肽的生产水平。已经提出了基因调控网络的数学和计算模型,其中一些相当抽象,被称为人工监管网络。在这一贡献中,提出了基因调控网络的空间模型,该模型在生物学上更现实,并结合了人工化学来实现称为转录因子的调控蛋白与模拟基因的调控位点之间的相互作用。结果是一个非常强大的系统,同时能够产生类似于自然界中可以观察到的复杂动力学。在这里,分析了系统的初始状态对所产生的动力学的影响,表明这样的模型是可进化的,并且可以针对产生所需的蛋白质动力学。
    Gene regulatory networks are networks of interactions in organisms responsible for determining the production levels of proteins and peptides. Mathematical and computational models of gene regulatory networks have been proposed, some of them rather abstract and called artificial regulatory networks. In this contribution, a spatial model for gene regulatory networks is proposed that is biologically more realistic and incorporates an artificial chemistry to realize the interaction between regulatory proteins called the transcription factors and the regulatory sites of simulated genes. The result is a system that is quite robust while able to produce complex dynamics similar to what can be observed in nature. Here an analysis of the impact of the initial states of the system on the produced dynamics is performed, showing that such models are evolvable and can be directed toward producing desired protein dynamics.
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  • 文章类型: Journal Article
    介绍了一种基于人工生命原理的与领域无关的问题求解系统。在这个系统中,DIAS,域的输入和输出维度在空间介质中布局。一群演员,每个人只看到这种媒介的一部分,集体解决问题。该过程与域无关,可以通过不同类型的参与者来实现。通过对各种问题域的一系列实验,DIAS被证明能够解决不同维度和复杂性的问题,不需要对新问题进行超参数调整,展示终身学习,也就是说,为了快速适应问题域中的运行时变化,比标准做得更好,非集体方法。因此,DIAS展示了生命在构建可扩展、一般,和自适应问题解决系统。
    A domain-independent problem-solving system based on principles of Artificial Life is introduced. In this system, DIAS, the input and output dimensions of the domain are laid out in a spatial medium. A population of actors, each seeing only part of this medium, solves problems collectively in it. The process is independent of the domain and can be implemented through different kinds of actors. Through a set of experiments on various problem domains, DIAS is shown able to solve problems with different dimensionality and complexity, to require no hyperparameter tuning for new problems, and to exhibit lifelong learning, that is, to adapt rapidly to run-time changes in the problem domain, and to do it better than a standard, noncollective approach. DIAS therefore demonstrates a role for ALife in building scalable, general, and adaptive problem-solving systems.
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  • 文章类型: Journal Article
    福岛第一核电站(FDNPS)事故中释放的放射性物质沉积在各种设备和建筑结构上。在退役期间,对污染设备和结构内部沉积的放射性物质的调查可以提供有关事故原因和进展的信息。这项研究介绍了放射性量的定量评估方法。在这种方法中,康普顿相机,一种伽马射线成像仪,用于调查放射性物质在污染物体上的沉积和污染水平。具有不同放射性的多个137Cs辐射源被水平放置在康普顿相机视场内的一个维度中,并进行了原理验证研究,以定量评估每种来源的放射性量。
    Radioactive substances released during the accident at the Fukushima Daiichi Nuclear Power Station (FDNPS) were deposited on various equipment and building structures. During decommissioning, an investigation of the radioactive substances deposited inside the contaminated equipment and structures can provide information regarding the cause and progression of the accident. This study introduces a quantitative evaluation method for the amount of radioactivity. In this method, a Compton camera, a type of gamma-ray imager, is used to investigate the deposition and contamination level of radioactive substances on contaminated objects. Multiple 137Cs radiation sources with different radioactivities were placed horizontally in one dimension within the field of view of the Compton camera, and a proof-of-principle study was conducted to evaluate the amount of radioactivity of each source quantitatively.
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  • 文章类型: Journal Article
    我们引入了两种新的搜索策略,以进一步提高植被进化(VEGE)的性能,以解决连续优化问题。具体来说,第一个战略,称为动态成熟度策略,允许具有更好的适应性的个体有更高的概率产生更多的种子个体。这里,所有个人将首先被分配以产生固定数量的种子,然后,剩余的可分配种子数量将根据其适合度进行竞争性分配。由于VEGE在摆脱局部最优方面表现不佳,我们提出了多种变异策略作为第二搜索算子,采用几种不同的变异方法来增加种子个体的多样性。换句话说,每个生成的种子个体将随机选择其中一种方法以更低的概率突变。为了评估这两种拟议战略的性能,我们运行我们的建议(VEGE+两种策略),VEGE,以及CEC2013基准测试函数和七个流行的工程问题上的另外七个高级进化算法(EA)。最后,我们分析了这两种策略对VEGE的各自贡献。实验和统计结果证实,在大多数优化问题中,我们的建议可以显着加快收敛速度,并提高常规VEGE的收敛精度。
    We introduce two new search strategies to further improve the performance of vegetation evolution (VEGE) for solving continuous optimization problems. Specifically, the first strategy, named the dynamic maturity strategy, allows individuals with better fitness to have a higher probability of generating more seed individuals. Here, all individuals will first become allocated to generate a fixed number of seeds, and then the remaining number of allocatable seeds will be distributed competitively according to their fitness. Since VEGE performs poorly in getting rid of local optima, we propose the diverse mutation strategy as the second search operator with several different mutation methods to increase the diversity of seed individuals. In other words, each generated seed individual will randomly choose one of the methods to mutate with a lower probability. To evaluate the performances of the two proposed strategies, we run our proposal (VEGE + two strategies), VEGE, and another seven advanced evolutionary algorithms (EAs) on the CEC2013 benchmark functions and seven popular engineering problems. Finally, we analyze the respective contributions of these two strategies to VEGE. The experimental and statistical results confirmed that our proposal can significantly accelerate convergence and improve the convergence accuracy of the conventional VEGE in most optimization problems.
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  • 文章类型: Journal Article
    配电网重构涉及通过调整开关状态来改变配电网的拓扑结构,它在智能电网中起着重要的作用,因为它可以有效地隔离故障,减少功率损耗,提高了系统的稳定性。然而,配电网的故障重构常被视为一个单目标或多目标优化问题,它的多模态在现有研究中经常被忽视。因此,当环境变化时,获得的解决方案可能不合适或不可行。为了提高解决方案的可用性和健壮性,针对配电网故障重构问题,提出了一种改进的离散多模态多目标粒子群优化算法(IDMMPSO)。为了证明所提出的IDMMPSO算法的性能,实验采用IEEE33总线配电系统。此外,将该算法与其他竞争对手进行了比较。实验结果表明,该算法在解决配电网故障重构问题时,能够为决策者提供不同的等效解。
    Distribution network reconfiguration involves altering the topology structure of distribution networks by adjusting the switch states, which plays an important role in the smart grid since it can effectively isolate faults, reduce the power loss, and improve the system stability. However, the fault reconfiguration of the distribution network is often regarded as a single-objective or multi-objective optimization problem, and its multimodality is often ignored in existing studies. Therefore, the obtained solutions may be unsuitable or infeasible when the environment changes. To improve the availability and robustness of the solutions, an improved discrete multimodal multi-objective particle swarm optimization (IDMMPSO) algorithm is proposed to solve the fault reconfiguration problem of the distribution network. To demonstrate the performance of the proposed IDMMPSO algorithm, the IEEE33-bus distribution system is used in the experiment. Moreover, the proposed algorithm is compared with other competitors. Experimental results show that the proposed algorithm can provide different equivalent solutions for decision-makers in solving the fault reconfiguration problem of the distribution network.
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  • 文章类型: Journal Article
    单目内窥镜6-DoF相机跟踪在手术导航中起着至关重要的作用,该导航涉及多模态图像以构建增强或虚拟现实手术。这样的6-DoF相机跟踪通常可以被公式化为非线性优化问题。为了解决这个非线性问题,这项工作提出了一个新的管道约束进化随机过滤,最初引入空间约束和进化随机扩散处理粒子退化和贫困在当前的随机过滤方法。将其应用于内窥镜6-DoF跟踪和临床数据验证,包括从各种外科手术中获得的59,000多个内窥镜视频帧,实验结果证明了新管道的有效性,比最先进的跟踪方法要好得多。特别是,它可以显着提高当前单目内窥镜跟踪方法的准确性,从(4.83mm,10.2○)至(2.78mm,7.44○)。
    Monocular endoscopic 6-DoF camera tracking plays a vital role in surgical navigation that involves multimodal images to build augmented or virtual reality surgery. Such a 6-DoF camera tracking generally can be formulated as a nonlinear optimization problem. To resolve this nonlinear problem, this work proposes a new pipeline of constrained evolutionary stochastic filtering that originally introduces spatial constraints and evolutionary stochastic diffusion to deal with particle degeneracy and impoverishment in current stochastic filtering methods. With its application to endoscope 6-DoF tracking and validation on clinical data including more than 59,000 endoscopic video frames acquired from various surgical procedures, the experimental results demonstrate the effectiveness of the new pipeline that works much better than state-of-the-art tracking methods. In particular, it can significantly improve the accuracy of current monocular endoscope tracking approaches from (4.83 mm, 10.2∘) to (2.78 mm, 7.44∘).
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  • 文章类型: Preprint
    基因调节机制(GRM)控制空间和时间表达模式的形成,这些模式可以作为复杂形状发育的调节信号。合成发育生物学旨在设计这种机制,以理解和产生所需的多细胞模式。然而,由于遗传回路中存在非线性相互作用和反馈回路,设计能够产生目标空间基因表达模式的合成GRM是当前的挑战.在这里,我们提出了一种自动设计GRM的方法,该GRM可以产生任何给定的空间模式。所提出的方法使用两个正交的形态发生原梯度作为多细胞组织区域或培养物中的位置信息信号,这构成了实施相同设计的GRM的工程细胞的连续领域。为了有效地设计电路网络和交互机制-包括形成目标模式所需的基因数量-我们开发了一种基于高性能进化计算的自动算法。算法的容差可以被配置为设计简单以产生近似图案或复杂以产生精确图案的GRM。我们通过为各种合成空间表达模式自动设计GRM来证明其性能。所提出的方法提供了一种通用的方法来系统地设计和发现产生模式的遗传电路。
    Synthetic developmental biology aims to engineer gene regulatory mechanisms (GRMs) for understanding and producing desired multicellular patterns and shapes. However, designing GRMs for spatial patterns is a current challenge due to the nonlinear interactions and feedback loops in genetic circuits. Here we present a methodology to automatically design GRMs that can produce any given spatial pattern. The proposed approach uses two orthogonal morphogen gradients acting as positional information signals in a multicellular tissue area or culture, which constitutes a continuous field of engineered cells implementing the same designed GRM. To efficiently design both the circuit network and the interaction mechanisms-including the number of genes necessary for the formation of the target pattern-we developed an automated algorithm based on high-performance evolutionary computation. The tolerance of the algorithm can be configured to design GRMs that are either simple to produce approximate patterns or complex to produce precise patterns. We demonstrate the approach by automatically designing GRMs that can produce a diverse set of synthetic spatial expression patterns by interpreting just two orthogonal morphogen gradients. The proposed framework offers a versatile approach to systematically design and discover pattern-producing genetic circuits.
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  • 文章类型: Journal Article
    这项工作的目的是通过所需部门的紧密条件来优化造船厂设施布局,以最大程度地降低总材料处理成本。为了解决这种类型的设施布局问题,当制造和材料处理过程需要根据整个生产流程中的供应和移动要求时,必须尊重部门的接近条件,特别是当活动需要部门之间通用的物料搬运设备时。作为这项工作的结果,优化是通过实现一个随机序列算法,包括以下步骤:1)遗传算法的拓扑优化,2)从计算程序将每个部门的质心坐标从拓扑网格转移到几何网格,3)随机增长算法的几何优化,对使用电子方法和本地搜索方法实现的解决方案进行微调。进行了计算实验以证明系统的有效性,并评估了所提出解决方案范围内列出的每种算法的性能。我们已经证明了所提出的算法的顺序结构可以成功地解决该问题。计算实验结果也显示在这项工作的补充材料中。
    The objective of this work is to optimize a shipyard facility layout through required departments\' closeness conditions to minimize total material handling cost. In order to resolve this type facility layout problem, departments\' closeness conditions must be respected when the manufacturing and material handling processes require it according to the supply and movement requirements throughout production flow, especially when the activity requires material handling equipment of common use between departments. As a result of this work the optimization is achieved through the implementation of a stochastic sequential algorithm, comprising the following steps: 1) Topological Optimization from a Genetic Algorithm, 2) Transferring the centroid coordinates of each department from the topological grid to the geometrical grid from a computational procedure, and 3) Geometrical Optimization from a Stochastic Growth Algorithm, with a fine-tuning of the solution achieved using the Electre Method and a Local Search Method. Computational experiments were performed to prove the effectiveness of the system and evaluate the performance of each algorithm listed in the scope of the proposed solution. We have proved that the proposed Sequential Structure of Algorithms can successfully solve the problem. Computational experiments results are also presented in the supplementary material of this work.
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