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Chrysostomos D. Stylios Voula C. Georgopoulos Georgia A. Malandraki Spyridoula Chouliara 《Applied Soft Computing》2008,8(3):1243-1251
Medical decision support systems can provide assistance in crucial clinical judgments, particularly for inexperienced medical professionals. Fuzzy cognitive maps (FCMs) is a soft computing technique for modeling complex systems, which follows an approach similar to human reasoning and the human decision-making process. FCMs can successfully represent knowledge and human experience, introducing concepts to represent the essential elements and the cause and effect relationships among the concepts to model the behavior of any system. Medical decision systems are complex systems that can be decomposed to non-related and related subsystems and elements, where many factors have to be taken into consideration that may be complementary, contradictory, and competitive; these factors influence each other and determine the overall clinical decision with a different degree. Thus, FCMs are suitable for medical decision support systems and appropriate FCM architectures are proposed and developed as well as the corresponding examples from two medical disciplines, i.e. speech and language pathology and obstetrics, are described. 相似文献
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一种进化模糊逻辑控制器的新方法 总被引:1,自引:0,他引:1
结合进化学习分类器的密歇根和匹兹堡方法的优点,首次将对单条控制规则的评价引入了模糊逻辑控制器(FLC)的进化过程中,解决了匹兹堡类型的学习分类器系统“强化信息的带宽窄”的问题,实现了FLC在控制器级和规则级的同时进化,控制器的控制规则数目也可以自由变化,实验结果表明新方法有较高的效率,优化的模糊控制器的结构简单,性能良好。 相似文献
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Rule learning is one of the most common tasks in knowledge discovery. In this paper, we investigate the induction of fuzzy classification rules for data mining purposes, and propose a hybrid genetic algorithm for learning approximate fuzzy rules. A novel niching method is employed to promote coevolution within the population, which enables the algorithm to discover multiple rules by means of a coevolutionary scheme in a single run. In order to improve the quality of the learned rules, a local search method was devised to perform fine-tuning on the offspring generated by genetic operators in each generation. After the GA terminates, a fuzzy classifier is built by extracting a rule set from the final population. The proposed algorithm was tested on datasets from the UCI repository, and the experimental results verify its validity in learning rule sets and comparative advantage over conventional methods. 相似文献
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Y. G. Petalas K. E. Parsopoulos M. N. Vrahatis 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2009,13(1):77-94
Fuzzy cognitive maps constitute a neuro-fuzzy modeling methodology that can simulate complex systems accurately. Although
their configuration is defined by experts, learning schemes based on evolutionary and swarm intelligence algorithms have been
employed for improving their efficiency and effectiveness. This paper comprises an extensive study of the recently proposed
swarm intelligence memetic algorithm that combines particle swarm optimization with both deterministic and stochastic local
search schemes, for fuzzy cognitive maps learning tasks. Also, a new technique for the adaptation of the memetic schemes,
with respect to the available number of function evaluations per application of the local search, is proposed. The memetic
learning schemes are applied on four real-life problems and compared with established learning methods based on the standard
particle swarm optimization, differential evolution, and genetic algorithms, justifying their superiority. 相似文献
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The problem of facility layout design is discussed, taking into account the uncertainty of production scenarios and the finite production capacity of the departments. The uncertain production demand is modelled by a fuzzy number, and constrained arithmetic operators are used in order to calculate the fuzzy material handling costs. By using a ranking criterion, the layout that represents the minimum fuzzy cost is selected. A flexible bay structure is adopted as a physical model of the system while an effective genetic algorithm is implemented to search for a near optimal solution in a fuzzy contest. Constraints on the aspect ratio of the departments are taken into account using a penalty function introduced into the fitness function of the genetic algorithm. The efficiency of the genetic algorithm proposed is tested in a deterministic context and the possibility of applying the fuzzy approach to a medium-large layout problem is explored.This revised version was published in June 2005 with corrected page numbers. 相似文献
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Scenarios describe events and situations that would occurred in the future real-world. Policy makers use scenario methods as a tool to build landscapes of possible futures at a national level. Based on these future visions, policy and decision-makers are able to explore different courses of action. In recent years, the number of potential scenario methods and applications is increasing. It is because academics and practitioners are increasing their interest about it. In spite of the success of scenario methods’ support, scenario-based decision making still is not a fully structured process.The proposed methodology aims to bring methodological support to scenario-based decision making in scenario analysis. The originality of the proposed approach with respect to other ones is that it aims to use the scenarios’ assessment and ranking as a whole. Traditional approaches consider the future impact of each present entity in isolation. This assumption is a simplification of a more complex reality, in which different entities interact with each other. The model that the authors propose allows decision and policy makers to measure the impact of a entity interactions. To reach this aim, the proposal combine Delphi method, soft computing (fuzzy cognitive maps) and multicriteria (TOPSIS) techniques. In addition, a numerical example is developed for illustrating the proposal. 相似文献
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This paper proposes the use of fuzzy cognitive maps (FCMs) as a technique for supporting the decision-making process in effect-based planning. The goal is to determine alternative courses of action to realize the aims of an operation, and choose the best option among them. With adequate consideration of the problem features and the constraints governing the method used, an FCM is developed to model effect-based operations (EBOs). In this study, certain features that do not exist in the classical FCM method were added to our FCM concept value calculation algorithm; these include influence possibility, influence duration, dynamic influence value-changing, and influence permanence. The model developed was applied to an illustrative scenario involving military planning, and we comment on the usefulness of the proposed methodology. 相似文献
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Fuzzy cognitive mapping is commonly used as a participatory modelling technique whereby stakeholders create a semi-quantitative model of a system of interest. This model is often turned into an iterative map, which should (ideally) have a unique stable fixed point. Several methods of doing this have been used in the literature but little attention has been paid to differences in output such different approaches produce, or whether there is indeed a unique stable fixed point. In this paper, we seek to highlight and address some of these issues. In particular we state conditions under which the ordering of the variables at stable fixed points of the linear fuzzy cognitive map (iterated to) is unique. Also, we state a condition (and an explicit bound on a parameter) under which a sigmoidal fuzzy cognitive map is guaranteed to have a unique fixed point, which is stable. These generic results suggest ways to refine the methodology of fuzzy cognitive mapping. We highlight how they were used in an ongoing case study of the shift towards a bio-based economy in the Humber region of the UK. 相似文献
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A. S. Andreou N. H. Mateou G. A. Zombanakis 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2005,9(3):194-210
This paper examines the use of fuzzy cognitive maps (FCMs) as a technique for modeling political and strategic issues situations and supporting the decision-making process in view of an imminent crisis. Its object domain is soft computing using as its basic elements different methods from the areas of fuzzy logic, cognitive maps, neural networks and genetic algorithms. FCMs, more specifically, use notions borrowed from artificial intelligence and combine characteristics of both fuzzy logic and neural networks, in the form of dynamic models that describe a given political setting. The present work proposes the use of the genetically evolved certainty neuron fuzzy cognitive map (GECNFCM) as an extension of certainty neuron fuzzy cognitive maps (CNFCMs) aiming at overcoming the main weaknesses of the latter, namely the recalculation of the weights corresponding to each concept every time a new strategy is adopted. This novel technique combines CNFCMs with genetic algorithms (GAs), the advantage of which lies with their ability to offer the optimal solution without a problem-solving strategy, once the requirements are defined. Using a multiple scenario analysis we demonstrate the value of such a hybrid technique in the context of a model that reflects the political and strategic complexity of the Cyprus issue, as well as the uncertainties involved in it. The issue has been treated on a purely technical level, with distances carefully kept concerning all sides involved in it. 相似文献
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Elpiniki I. Papageorgiou Csaba Huszka Jos De Roo Nassim Douali Marie-Christine Jaulent Dirk Colaert 《Computer methods and programs in biomedicine》2013
This study aimed to focus on medical knowledge representation and reasoning using the probabilistic and fuzzy influence processes, implemented in the semantic web, for decision support tasks. Bayesian belief networks (BBNs) and fuzzy cognitive maps (FCMs), as dynamic influence graphs, were applied to handle the task of medical knowledge formalization for decision support. In order to perform reasoning on these knowledge models, a general purpose reasoning engine, EYE, with the necessary plug-ins was developed in the semantic web. The two formal approaches constitute the proposed decision support system (DSS) aiming to recognize the appropriate guidelines of a medical problem, and to propose easily understandable course of actions to guide the practitioners. The urinary tract infection (UTI) problem was selected as the proof-of-concept example to examine the proposed formalization techniques implemented in the semantic web. The medical guidelines for UTI treatment were formalized into BBN and FCM knowledge models. To assess the formal models’ performance, 55 patient cases were extracted from a database and analyzed. The results showed that the suggested approaches formalized medical knowledge efficiently in the semantic web, and gave a front-end decision on antibiotics’ suggestion for UTI. 相似文献
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《计算机科学》2025,52(1)
联合作战军事需求生成涉及的参与人员多、工作量庞大,生成过程大多依赖个体经验与多来源文档,存在需求生成效率较低等问题,难以有效支撑联合作战体系设计。随着大模型技术的发展,大模型驱动的智能体在诸多领域展现出卓越的性能,多智能体系统通过分布式决策实现群体智能,能够高效处理复杂任务。针对军事需求生成过程中存在的效率低下的问题,提出大模型驱动多智能体的军事需求生成框架。该框架整合了多模态信息获取智能体、军事专家智能体、会议主持人等要素。多模态信息获取智能体集成多模态信息处理工具,能够快速获取军事需求,并与用户进行问答交互;军事专家智能体以自然语言对话的形式模拟人类专家讨论生成需求的场景,大模型驱动军事专家智能体理解环境,并能自主调用开源论文库、搜索引擎等工具以支持对话;会议主持人接收人类用户的指令,利用大模型细化指令内容,生成对话提示词和问题背景描述。以俄乌冲突为实验背景,对相关多模态信息进行军事需求生成。实验结果表明,当多模态信息量在大模型最大处理容量以内时,该框架显著降低了军事需求生成的时间消耗,视频资源节省时间占比达到80%~85%,音频资源节省时间占比为90%~95%。 相似文献
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C. L. Karr
S. K. Sharma
W. J. Hatcher
T. R. Harper
《Engineering Applications of Artificial Intelligence》1993,6(6):575-582Establishing suitable control of complex chemical reactions, a requirement in a number of industries, poses a difficult problem because of nonlinearities and frequently changing process dynamics. Researchers at the U.S. Bureau of Mines have developed a technique for producing adaptive fuzzy logic controllers (FLCs) that are capable of effectively managing such complex chemical systems. In this technique, a genetic algorithm (GA) is used to alter the membership functions employed by a conventional FLC; an approach that is contrary to the tactic generally used to provide FLCs with adaptive capabilities in which the rule set is altered. GAs are search algorithms based on the mechanics of natural genetics that are able to rapidly locate near-optimum solutions to difficult problems. The Bureau-developed technique is used to produce an adaptive GA-FLC for a particular system in which an exothermic chemical reaction is conducted. Specifically, formaldehyde is reacted with ammonia in a continuous stirred tank reactor to produce hexamine and water. Results indicate that FLCs augmented with GAs offer a powerful alternative to conventional process-control techniques in the nonlinear, rapidly changing chemical systems commonly found in industry. 相似文献
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Given the international efforts in tackling climate change as well as the potential dependence on conventional energy imports and the adverse economic environment, countries in the European Union face significant challenges in the critical task of enhancing energy efficiency. Approaches exclusively oriented on detailed quantitative modelling tools like energy system and climate-economy models, however, tend to exclude certain policy instruments and risks, and be too formalised or complex for policymakers to participate, understand and trust. Several decision support frameworks have been proposed for bridging the policy-model gap and helping policymakers confidently select among a number of alternative strategies. This paper employs the expert-driven method of fuzzy cognitive mapping, a semi-quantitative modelling technique in which system dynamics are captured and simulated against different scenarios. To this end, an innovative decision support tool for building and simulating complex fuzzy cognitive maps for assessing policy strategies with the help of experts, ESQAPE, is introduced and presented. An application in Greece shows that long-term energy efficiency measures focusing mainly on behavioural change in the residential sector – as opposed to services in the private and public sectors – are perceived to be more sustainable in a socio-economically optimistic future; this is not the case when challenges across the mitigation and adaptation axes are expected to be higher. 相似文献
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《国际计算机数学杂志》2012,89(12):853-866
A hybrid method consisting of a real-coded genetic algorithm (RCGA) and an interval technique is proposed for optimizing bound constrained non-linear multi-modal functions. This method has two different phases. In phase I, the search space is divided into several subregions and the simple genetic algorithm (SGA) is applied to each subregion to find the one(s) containing the best value of the objective function. In phase II, the selected subregion is divided into two equal halves and the advanced GA, i.e. the RCGA, is applied in each half to reject the subregion where the global solution does not exist. This process is repeated until the interval width of each variable is less than a pre-assigned very small positive number. In the RCGA, we consider rank-based selection, multi-parent whole arithmetical cross-over, and non-uniform mutation depending on the age of the population. However, the cross-over and mutation rates are assumed as variables. Initially, these rates are high and then decrease from generation to generation. Finally, the proposed hybrid method is applied to several standard test functions used in the literature; the results obtained are encouraging. Sensitivity analyses are shown graphically with respect to different parameters on the lower bound of the interval valued objective function of two different problems. 相似文献
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An Adaptive Clustering Protocol Using Niching Particle Swarm Optimization for Wireless Sensor Networks
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Clustering is an hierarchical topology control method, and it is also an energy‐saving and energy efficient technique that extends the sensor network's lifetime. In this paper, we propose and analyze an adaptive clustering protocol using niching particle swarm optimization (ACP‐NPSO), a protocol architecture that uses NPSO to cluster the wireless sensor networks adaptively and efficiently, thus saving energy, balancing energy consumption and enhancing the system's robustness. The simulation results indicate that our proposed protocol ACP‐NPSO can enhance system lifespan, accelerate the convergence speed, and deliver more data by distributing energy dissipation evenly in the networks. 相似文献
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介绍的是基于量子粒子群算法模糊认知图的学习方法。其主要的思路是更新模糊认知图中能够使之趋向所要求的稳定状态的非零权值。将所研究的方法运用到工业控制问题,具有很大的现实意义。实验的结果表明,该方法是有效的,并优于传统的粒子群算法。 相似文献
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引入RNA计算的遗传模糊C均值聚类算法 总被引:1,自引:0,他引:1
模糊C均值算法(FCM)在聚类分析中是目前比较流行和应用比较广泛的一种算法。但它存在两个弱点:一是对初始化非常敏感,容易陷入局部极值点;二是处理大数据集时耗时太长。基于RNA的分子计算是近年来新兴的一种智能优化计算方法。提出了基于RNA计算的遗传模糊聚类算法(RNAGAFCM),来提高收敛速度和全局寻优能力。仿真实验表明新算法比现有的遗传模糊聚类算法减少了迭代次数,提高了收敛速度。 相似文献