摘要
无线传感网的日益广泛应用和信息物理融合系统的产生，使得信息融合技术越来越受到人们的重视。随着传感器数据来源越来越复杂，如何快速、全面、准确地获取信息已成为研究热点，因而对信息融合方法的研究具有重大的意义。本文考虑到证据理论有较强的不确定性推理能力，能较好地对多源信息进行融合，因此基于证据理论对信息融合方法进行研究，提出了一种新的冲突度量方法及证据融合方法，并将该方法应用于多源信息融合中，具体研究内容如下:（1）综合冲突度量法的提出。Dempster组合规则，作为证据理论的核心部分，是组合基本信任分配函数表征的证据的最经典规则，然而，在对高冲突证据组合时往往会得出与常理相悖的结论。为了研究出更为有效的冲突证据组合方法，则首先需对证据间的冲突进行合理度量。本文在总结现有冲突度量方式的基础上，提出了一种综合冲突度量法。该方法一方面通过直接冲突与潜在冲突，来考虑焦元间的非相容性对冲突产生的影响，另一方面又借助投注信度距离度量，来考虑证据间的差异性对冲突产生的作用，进而可对冲突进行综合度量，较现有冲突度量方法更为全面，为后续研究冲突证据的融合方法打下了坚实基础。
（2）一种新的冲突证据融合方法的提出。考虑到目前大多数证据融合方法在组合证据时，将各传感器输出的证据视作等可靠的，这将导致可靠性低的传感器产生的证据降低融合系统的性能。针对这一情况，本文引入证据的可靠性指数的概念，对证据间的确定性程度进行描述，并以此确定各证据的折扣率，降低可靠性低的证据对融合结果的影响；此外，根据本文提出的综合冲突度量法得出各证据间的冲突因子，
并根据模糊数学中的隶属度函数得出证据间的一致性系数，通过综合考虑证据间的冲突与一致性程度，确定证据间的关联程度，并以此确定各证据的权重系数。然后，根据折扣率与权重系数这两个参数对证据源进行修正，提出一种改进的融合方法。最后，在实验设置中，使用本方法对传感器观测到的车辆图像信息进行目标识别，并与其它改进融合方法进行对比，结果表明本文方法能有效对目标进行决策识别，且有较高的融合精度及较快的收敛速度。
（3）针对可靠性数据处理中寿命数据曲线拟合中的信息利用问题，对采集的样本数据所包含的特征信息进行了深入挖掘，并利用改进的证据融合方法对这些信息进行融合，根据融合结论得出拟合样本点，从而拟合出所需的曲线，并得出有效的可靠性结论。
关键词：信息融合；证据理论；冲突度量；可靠性指数；关联度；数据处理
Abstract
The increasingly extensive application of wireless nsor network and the emergence of cyber physical systems make the information technology attract more and more attention.With the increasing complexity of nsor data sources,exploring a way to acquire information fast,comprehensively and accurately has become a hot topic.Therefore,the rearch on information fusion approach is of great significance. Considering the evidence theory has a strong reasoning abil
ity under uncertainties, and can be ud for multisource information fusion,the paper studies information fusion method bad on evidence theory,prents not only a new method to measure conflict between evidences,but an improved approach to conflict evidence combination,and employs the latter in multisource information fusion.The specific contents are as follows.
Firstly,the analysis and rearch of conflict measure.Dempster’s combination rule,the kernel of D-S theory,is a classical rule to combine evidences reprented by basic probability assignment function.However,when evidences highly conflict with each other,this combination rule will become invalid and obtain a counter-intuitive conclusion.In order to come up with a more effective method to conflict evidence combination,it is necessary to measure the conflict between evidences reasonably at first.Bad on the summary of existing conflict measurement methods,the paper propos a comprehensive method to measure conflict.On the one hand,the method considers the impact incompatibility between focals makes on conflict through direct conflict and potential conflict.On the other hand,the method takes into account the effect difference between evidences makes on conflict through the distance between betting commitment beliefs,thus to measure conflict comprehensively.Compared with existing conflict measurement methods,the method appears to be more effective, and provides a solid foundation for the further study on conflict evidence combination.
Secondly,the study on conflict evidence combination.Currently,evidences produced by nsors are regarded to be reliable equally in most evidence combination methods,which makes evidence from low reliable nsors lead to the performance reduction in fusion system.To solve the problem,the paper introduces reliability index for evidence to describe certainty degree,and determine the discount rate for消化腺的功能
each evidence according to the index,thus to reduce the impact of low reliable evidence on fusion result.In addition,conflict factor between evidences is obtained according to the propod conflict measurement method,and consistent coefficient is acquired from membership function in fuzzy mathematics.By integrating the degree of conflict and consistency,the correlation degree between evidences is confirmed. Bad on this,the weight coefficient for each evidence is determined.Then,discount rate and weight coefficient are ud to revi evidence source,and an improved fusion approach is propod.In the experiment,the improved method is ud to identify the vehicle image information obrved by nsors,comparative analysis with other methods shows the method can effectively identify the target,and has higher fusion accuracy,fast convergence speed.
Finally,the rearch on information utilization issues in curve fitting for lifetime data in reliability data processing.By mining the feature information in depth in sample data,the improved evidence combin
ation method is ud to fu the extracted information.According to fusion result,the sample points involved in fitting is obtained to fit the desired curve,and a valid reliability conclusion can be drawn.
Key Words:Information Fusion;Evidence Theory;Conflict Measurement;
Reliability Index;Association Degree;Data Processing
目录
学位论文原创性声明..............................................................................................................I 摘要.......................................................................................................................................III 目录........................................................................................................................................V 插图索引...............................................................................................................................VII 附表索引..............................................................................................................................VIII 第1章绪论. (1)
1.1研究背景和意义 (1)
1.2国内外研究现状 (2)
1.2.1信息融合研究现状 (2)
1.2.2证据理论研究现状 (4)
1.3本文的研究内容 (5)
1.4本文的组织结构 (6)
第2章信息融合技术及D-S证据理论概述 (7)
2.1信息融合基本理论 (7)
2.1.1信息融合的定义 (7)
2.1.2信息融合的级别 (7)
2.1.3信息融合相关算法介绍 (10)
我的头发2.2D-S证据理论基础 (13)
2.2.1识别框架 (13)
2.2.2基本信任分配函数 (14)
2.2.3信任函数 (15)
2.2.4似然函数 (15)
2.2.5D-S证据理论的合成规则 (16)
2.3证据理论在信息融合过程中存在的问题 (18)
2.4本章小结 (19)
第3章证据间冲突分析与度量研究 (20)
运动协调3.1引言 (20)
3.2冲突产生原因分析 (20)
复合实木地板3.3现有冲突度量分析 (21)
3.3.1经典冲突系数度量法 (21)
3.3.2距离型度量法 (23)
3.3.3复合型度量法 (23)
3.4一种综合冲突度量方法 (24)
3.4.1部分潜在冲突分析 (24)
3.4.2综合冲突度量法 (26)
3.5算例与仿真比较 (28)
3.6本章小结 (30)
第4章冲突证据融合方法的改进 (31)
4.1引言 (31)
4.2现有改进方法分析 (31)贪腐
4.2.1合成规则的改进 (32)
4.2.2证据源的修改 (34)
4.3一种新的冲突证据融合方法 (34)
4.3.1证据可靠性 (35)
4.3.2证据权重系数 (35)
4.3.3改进的D-S融合方法 (36)
4.4融合模型 (39)
4.5实验对比分析 (41)点菜宝怎么用
4.6本章小结 (44)
第5章D-S证据理论在多源信息融合中的应用 (45)
5.1引言 (45)
5.2样本数据分析 (45)
5.3证据构成 (47)
大葱的营养价值
英语初级入门5.4证据融合过程 (50)
5.5曲线拟合 (51)
5.6本章小结 (51)
结论 (52)
参考文献 (54)
致谢 (58)
附录A攻读学位期间发表的学术论文 (59)
附录B攻读学位期间参与的科研项目 (60)
