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1.
基于属性测度的辐射源识别方法研究   总被引:3,自引:0,他引:3  
何友  关欣  衣晓 《中国科学(E辑)》2004,34(12):1329-1336
对辐射源识别问题进行了研究, 提出了一种采用属性测度理论对辐射源进行识别的新方法. 给出了对雷达侦察设备上报的辐射源参数数据进行属性识别的方法、步骤和多指标权系数的确定方法. 针对战场环境下多传感器系统获取的雷达辐射源信息具有时间上的冗余性, 文中又将该方法推广到多传感器系统. 将属性测度与D-S证据理论相结合, 利用文中给出的属性测度计算方法构造证据理论中的基本概率赋值函数. 最后以雷达辐射源用途识别和体制识别为例, 对单传感器和多传感器的情况分别进行计算机仿真实验, 结果验证了这一方法的正确性和有效性.  相似文献   

2.
为实现矿井通风系统方案的优选,建立基于层次分析法(AHP)和熵权多属性决策方法(VIKOR)的矿井通风评价模型。以庞庄煤矿为例,首先分别从技术、经济、安全三个方面选出12个评价指标,通过AHP计算指标的主观权重,熵权法计算指标的客观权重,然后进行综合赋权得到指标的权重,同时利用计算得出的指标权重和VIKOR法计算候选方案的最大群体效益值、最小个体遗憾值和利益值并进行排序,进而选出最优方案。所得结果证明该方法充分考虑了最大群体效益和最小个体遗憾之间的关系,能够选取到最优的方案,具有可行性和有效性。  相似文献   

3.
基于路网拓扑布局和桥梁结构属性,进行路段抗震提升重要度评价,可为公路交通系统震前加固改造、灾害应急准备等工作提供依据.本文采用4种不同特性的单元重要度评价指标:介数、连通概率灵敏度、路网震后通行时间和路网震前通行时间影响重要度,计算路段及其内部桥梁和道路单元的抗震提升重要度.为综合考虑多指标评价结果对单元重要度排序的影响,本文采用逼近理想排序法(TOPSIS)多属性决策方法评价路段的综合重要度.通过实例路网模型应用,分析了不同指标的特点,比较了单指标评价与多指标综合评价结果的差异.结果表明,不同指标的重要度评价结果存在明显差异,基于多指标分析的路段抗震改造重要度,综合考虑了网络拓扑结构、单元地震反应、单元通行能力、OD(起止点对)交通量的影响,为决策者提供了综合判别的依据.  相似文献   

4.
针对包含认知不确定性的结构可靠性问题,提出了一种基于证据理论的可靠性优化设计方法.首先,在优化过程中基于代理模型对迭代点处各约束进行可靠性分析,计算其似真度;其次,通过证据变量均匀化方法构造了一种证据理论可靠性的近似梯度计算方法,从而可采用基于梯度的常规优化算法进行优化求解;最后,数值算例和工程算例表明了本方法的有效性.  相似文献   

5.
复杂水网节点的重要性排序在工程应用中有重要实践意义,对于水网调度、安全管理有重要借鉴意义.为此,本文在复杂网络理论基础上,以山西大水网节点重要性排序问题为背景,对水网节点重要性评价进行研究.首先从整体角度出发,不考虑水网方向和干支斗毛级别差异,基于水网全局网络拓扑结构,从局部属性、全局属性、传播属性和网络位置四个方面定义了节点重要性评价指标.其次,分别根据这四个指标,对水网节点重要性进行排序分析,结合分析结果对网络位置指标进行了改进.然后,由于单指标评价结果不够全面且适用范围具有很大的局限性,给出了基于TOPSIS的多属性决策方法来综合评价节点的重要性.最后,考虑水网方向和级别差异,提出对水网进行干支斗毛级别划分,基于Page Rank算法对同一级别的有向赋权水网节点重要性评价进行研究.  相似文献   

6.
以某企业对粉煤灰的资源化利用为例,基于层次分析法从经济效益、社会效益、技术和管理四个准则层及其分解的十四个指标层出发,确定权重矢量和评价矩阵,通过计算得到层次单排序和总排序及该企业的综合评价值.综合评价表明,该企业对粉煤灰资源化利用技术的应用情况为优,其利用综合评价值S为86.1分.  相似文献   

7.
为解决突发事件应急方案选择中信息不确定和随机性的问题,提出一种基于贝叶斯(Bayes)和蒙特卡洛(Monte Carlo)的风险决策方法。首先基于事发现场实际情况,应用贝叶斯决策理论,构建多元正态分布模型;然后针对权重随机性的特点,采用蒙特卡洛模拟算法进行模拟;通过计算各方案获得特定排名的可信度及整体排名可信度因子,得到方案排序,从而减小了不确定性信息对应急决策过程的影响。最后通过核电站事故应急决策的例子,验证了所提出方法模型的有效性和可行性。  相似文献   

8.
利用空间目标红外辐射测量数据,提出了系统的计算分析方法,对空间目标的温度、发射率等属性进行预测,进而判断空间目标的类型和运行状态.通过建立空间目标红外辐射光谱计算模型,模拟了探测器接收到的红外辐射光谱信号,采用独立成分分析方法提取了空间目标不同材料的光谱发射率特征,判断了空间目标的部件个数和材料类型,采用最小二乘拟合方法反演了空间目标各部件的投影面积与表面温度.模拟结果表明:该方法对空间目标参数的反演误差较小,能够实现对空间目标属性的预测.研究成果对于空间目标类型和状态的判断,具有十分重要的意义.  相似文献   

9.
基于AutoCAD的露天矿三维地质模型的三维可视化构建方法   总被引:5,自引:1,他引:4  
本文在AutoCAD平台下,以钻孔信息、剖面图和空间离散点为基础数据,采用顾及台阶属性的Delaunay三角网凸包算法建立界面模型,通过面域拉伸和实体布尔运算等方法生成三维实体模型。研究结果表明,该方法不仅能达到逼真的三维动态效果,而且对于矿岩量的计算更为准确方便。研究结论初步突破了露天矿算量的传统方法,有助于露天矿的日常生产和管理。  相似文献   

10.
考虑数据信息较少以及认知水平有限情况下的不确定性对于结构拓扑优化具有重要意义.本文引入证据理论处理不精确的数据信息,采用证据理论的不确定测度克服精确概率约束模型建立的困难,并结合拓扑优化策略,形成了基于证据理论的可靠性拓扑优化设计模型.为了提高不确定测度的计算效率,提出了仿生智能优化算法和不精确极值思想相结合的改进优化算法来降低焦元数目和极限状态函数极值求解所导致的计算量.通过两个桁架算例对所提方法进行验证,结果表明,确定性优化结果可能是不确定情况下的失效解,虽然基于证据理论的最优设计在重量和拓扑形式上相对于确定性优化结果偏保守,但具备抵抗不确定波动的能力.  相似文献   

11.
It is commonly argued that values “fill the logical gap” of underdetermination of theory by evidence, namely, values affect our choice between two or more theories that fit the same evidence. The underdetermination model, however, does not exhaust the roles values play in evidential reasoning. I introduce WAVE – a novel account of the logical relations between values and evidence. WAVE states that values influence evidential reasoning by adjusting evidential weights. I argue that the weight-adjusting role of values is distinct from their underdetermination gap-filling role. Values adjust weights in three ways. First, values affect our trust in the testimony of others. Second, values influence the evidential thresholds required for justified epistemic judgments. Third, values influence the relative weight of a certain type of evidence within a body of multimodal discordant evidence. WAVE explains, from an epistemic perspective, rather than psychological, how smokers, for example, can find the same evidence about the dangers of smoking less persuasive than non-smokers. WAVE allows for a wider effect of values on our accepted scientific theories and beliefs than the effect for which the underdetermination model allows alone; therefore, science studies scholars must consider WAVE in their research and analysis of evidential case studies.  相似文献   

12.
A common method for warranting the historical adequacy of philosophical claims is that of relying on historical case studies. This paper addresses the question as to what evidential support historical case studies can provide to philosophical claims and doctrines. It argues that in order to assess the evidential functions of historical case studies, we first need to understand the methodology involved in producing them. To this end, an account of historical reconstruction that emphasizes the narrative character of historical accounts and the theory-laden character of historical facts is introduced. The main conclusion of this paper is that historical case studies are able to provide philosophical claims with some evidential support, but that, due to theory-ladenness, their evidential import is restricted.  相似文献   

13.
It is widely acknowledged that the patient's perspective should be considered when making decisions about how her care will be managed. Patient participation in the decision making process may play an important role in bringing to light and incorporating her perspective. The GRADE framework is touted as an evidence-based process for determining recommendations for clinical practice; i.e. determining how care ought to be managed. GRADE recommendations are categorized as “strong” or “weak” based on several factors, including the “values and preferences” of a “typical” patient. The strength of the recommendation also provides instruction to the clinician about when and how patients should participate in the clinical encounter, and thus whether an individual patient's values and preferences will be heard in her clinical encounter. That is, a “strong” recommendation encourages “paternalism” and a “weak” recommendation encourages shared decision making. We argue that adoption of the GRADE framework is problematic to patient participation and may result in care that is not respectful of the individual patient's values and preferences. We argue that the root of the problem is the conception of “values and preferences” in GRADE – the framework favours population thinking (e.g. “typical” patient “values and preferences”), despite the fact that “values and preferences” are individual in the sense that they are deeply personal. We also show that tying the strength of a recommendation to a model of decision making (paternalism or shared decision making) constrains patient participation and is not justified (theoretically and/or empirically) in the GRADE literature.  相似文献   

14.
随着云计算的兴起,云迁移计算开始成为移动设备获取计算资源和降低功耗的有效方式.云迁移的主要想法是将移动终端的复杂任务经由无线网络迁移到云端执行,然后再接收计算结果.然而,无线网络的不稳定性和数据传输的高功耗限制了云迁移计算在移动设备中的应用.不同于已有工作,本文通过引入数据压缩的方法完善了云迁移计算决策模型,并且基于对未来时段网络期望的预测,提出了一种节能迁移计算决策算法——EPVAD.基于实际的3G网络带宽数据和开发测试平台,实验结果显示:EPVAD算法的节能效果较同类算法平均优14.9%,并且算法自身的系统开销可忽略.  相似文献   

15.
在城市道路或公路交通量达到一定水平时,必须采用交通的空间分离设施,通常是采用交通流的立体交叉。而立体交叉的选型问题是一个涉及多方面因素的多目标决策问题。本文引入PROMETHEE法建立了立交选型优化模型,并通过实例验证,该方法的操作性好而且适用于不同的决策环境。  相似文献   

16.
Feminist standpoint empiricism contributes to the criticism of the value-free ideal by offering a unique analysis of how non-epistemic values can play not only a legitimate but also an epistemically productive role in science. While the inductive risk argument focuses on the role of non-epistemic values in the acceptance of hypotheses, standpoint empiricism focuses on the role of non-epistemic values in the production of evidence. And while many other analyses of values in science focus on the role of non-epistemic values either in an individual scientist's decision making or in the distribution of research efforts in scientific communities, standpoint empiricism focuses on the role of non-epistemic values in the building of scientific/intellectual movements.  相似文献   

17.
The most promising way to regard thought experiment is as a species of experiment, alongside concrete experiment. Of the authors who take this view, many portray thought experiment as possessing evidential significance intrinsically. In contrast, concrete experiment is nowadays most convincingly portrayed as acquiring evidential significance in a particular area of science at a particular time in consequence of the persuasive efforts of scientists. I argue that the claim that thought experiment possesses evidential significance intrinsically is contradicted by the history of science. Thought experiment, like concrete experiment, has evidential significance only where particular assumptions—such as the Galilean doctrine of phenomena—are taken to hold; under alternative premises, in themselves equally defensible, thought experiment is evidentially inert.  相似文献   

18.
It is generally accepted that Popper‘s degree of corroboration, though “inductivist” in a very general and weak sense, is not inductivist in a strong sense, i.e. when by ‘inductivism’ we mean the thesis that the right measure of evidential support has a probabilistic character. The aim of this paper is to challenge this common view by arguing that Popper can be regarded as an inductivist, not only in the weak broad sense but also in a narrower, probabilistic sense. In section 2, first, I begin by briefly characterizing the relevant notion of inductivism that is at stake here; second, I present and discuss the main Popperian argument against it and show that in the only reading in which the argument is formally it is restricted to cases of predicted evidence, and that even if restricted in this way the argument is formally valid it is nevertheless materially unsound. In section 3, I analyze the desiderata that, according to Popper, any acceptable measure for evidential support must satisfy, I clean away its ad-hoc components and show that all the remaining desiderata are satisfied by inductuvist-in-strict-sense measures. In section 4 I demonstrate that two of these desiderata, accepted by Popper, imply that in cases of predicted evidence any measure that satisfies them is qualitatively indistinguishable from conditional probability. Finally I defend that this amounts to a kind of strong inductivism that enters into conflict with Popper’s anti-inductivist argument and declarations, and that this conflict does not depend on the incremental versus non-incremental distinction for evidential-support measures, making Popper’s position inconsistent in any reading.  相似文献   

19.
针对文献[1]和[2]分别采用模糊聚类和神经网络方法进行煤层注水可行性分析过程中共同存在的煤层适应性单一和计算机运算过程复杂问题,提出建立Fihser判别模型进行煤层注水可行性分析的新方法.选取裂隙发育程度、孔隙率、煤层湿润边角、饱和水分增值、坚固性系数、埋藏深度6个因素,以11组煤层注水实测标准数据作为样本,通过模糊...  相似文献   

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