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121.
Dempster-Shafer证据理论在目标意图预测中的应用   总被引:1,自引:0,他引:1  
为了准确对目标意图进行预测,以便我方及时合理地作出战术决策,采用D-S证据理论对目标意图进行预测。首先提取出影响目标意图预测的各个态势因素,然后分析每个因素的影响效果。在此基础上建立目标意图预测的数学模型,利用D-S合成法则将所有因素的影响进行综合,并计算出各个可能命题的概率赋值并给出相应决策。最后,通过仿真实例验证了该方法在目标意图预测中的可行性和实用性。  相似文献   
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为预防和减少WUI火灾的发生, 挖掘WUI火灾关键致灾因子, 厘清致灾因子间的作用机制. 本文首先基于本文挖掘技术从WUI火灾事故案例中得到致灾因子, 使用Apriori算法得到致灾因子之间的关联规则. 然后使用复杂网络理论构建WUI火灾致灾因子网络, 计算网络拓扑特征参数, 探析WUI火灾致灾因子网络特征. 最后引入WUI火灾致因链风险度指标, 挖掘出高风险连边, 并提出断链措施. 结果表明: WUI火灾致灾因子网络具有小世界特性, 高温、强风、干旱等对其他致灾因子影响较大. 燃烧废弃物、植物起火、应急响应速度、人为纵火、强风在不同致灾因子转换中具有重要作用, 应加强管控. 网络中风险度最高的边是燃烧废弃物→植物起火, 通过颁布禁止擅自燃烧废弃物等规定, 即可切断该风险链, 实现对WUI火灾的预防和主动控制.  相似文献   
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Periodontitis is a multifactorial disease. The aim of this explorative study was to investigate the role of Interleukin-(IL)-1, IL-4, GATA-3 and Cyclooxygenase-(COX)-2 polymorphisms after non-surgical periodontal therapy with adjunctive systemic antibiotics (amoxicillin/metronidazole) and subsequent maintenance in a Caucasian population. Analyses were performed using blood samples from periodontitis patients of a multi-center trial (ClinicalTrials.gov NCT00707369=ABPARO-study). Polymorphisms were analyzed using quantitative real-time PCR. Clinical attachment levels (CAL), percentage of sites showing further attachment loss (PSAL) ≥1.3 mm, bleeding on probing (BOP) and plaque score were assessed. Exploratory statistical analysis was performed. A total of 209 samples were genotyped. Patients carrying heterozygous genotypes and single-nucleotide-polymorphisms (SNP) on the GATA-3-IVS4 +1468 gene locus showed less CAL loss than patients carrying wild type. Heterozygous genotypes and SNPs on the IL-1A-889, IL-1B +3954, IL-4-34, IL-4-590, GATA-3-IVS4 +1468 and COX-2-1195 gene loci did not influence CAL. In multivariate analysis, CAL was lower in patients carrying GATA-3 heterozygous genotypes and SNPs than those carrying wild-types. For the first time, effects of different genotypes were analyzed in periodontitis progression after periodontal therapy and during supportive treatment using systemic antibiotics demonstrating a slight association of GATA-3 gene locus with CAL. This result suggests that GATA-3 genotypes are a contributory but non-essential risk factor for periodontal disease progression.  相似文献   
124.
Complement-mediated diseases or complementopathies, such as Paroxysmal nocturnal hemoglobinuria (PNH), cold agglutinin disease (CAD), and transplant-associated thrombotic microangiopathy (TA-TMA), demand advanced complement diagnostics and therapeutics be adopted in a vast field of medical specialties, such as hematology, transplantation, rheumatology, and nephrology. The miracle of complement inhibitors as “orphan drugs” has dramatically improved morbidity and mortality in patients with otherwise life-threatening complementopathies. Efficacy has been significantly improved by upstream inhibition in patients with PNH. Different molecules may exert diverse characteristics in vitro and in vivo. Further studies remain to show safety and efficacy of upstream inhibition in other complementopathies. In addition, cost and availability issues are major drawbacks of current treatments. Therefore, further developments are warranted to address the unmet clinical needs in the field of complementopathies. This state-of-the-art narrative review aims to delineate novel insights into factor D inhibition as a promising target for complementopathies.  相似文献   
125.
Lacto-N-biose I (LNB) is supposed to represent the bifidus factor in human milk oligosaccharides, and can be practically produced from sucrose and GlcNAc using four bifidobacterial enzymes, 1,3-β-galactosyl-N-acetylhexosamine phosphorylase, sucrose phosphorylase, UDP-glucose-hexose 1-phosphate uridylyltransferase, and UDP-glucose 4-epimerase, recombinantly produced by Escherichia coli. Here the production of LNB by the same enzymatic method without using genetically modified enzymes to consider the use of LNB for a food ingredient was reported. All four enzymes were produced as the intracellular enzymes of Bifidobacterium strains. The mixture of the crude extracts contained all four enzymes, with other enzymes interfering with the LNB production, namely, phosphoglucomutase, fructose 6-phosphate phosphoketolase, and glycogen phosphorylase. The first two interfering enzymes were selectively inactivated by heat treatment at 47 °C for 1 h in the presence of pancreatin, and glycogen phosphorylase was disabled by hydrolyzing its possible acceptor molecules using glucoamylase. Finally, 91 % of GlcNAc was converted into LNB in the 100-mL reaction mixture containing 300 mM GlcNAc.  相似文献   
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Matching and Interpolation of Shapes using Unions of Circles   总被引:4,自引:0,他引:4  
While the notion of shape of an object is very intuitive, its precise definition is very elusive, and defining a useful metric for the shape distance between objects is a difficult endeavor. At the same time many successful techniques have been developed which interpolate between two objects, so in essence interpolate between shapes. W e present here work which uses a representation of objects as union of circles to define a distance between two objects and to base a method to interpolate between the two. This method can be used in a totally automatic fashion (that is, without any user intervention), or users can guide a pre-registration phase as well as a segmentation phase, after which the matched segments are interpolated pair-wise. The union of circles representation of the two objects is obtained from the Delaunay triangulation of their boundary points. The circles can be simplified to obtain smaller data sets. The circles are then optimally matched according to a distance metric between circles which is a function of their position, size, and feature, that is, a local configuration of circles. The interpolation between the two objects is then obtained by interpolating between the matched pairs of circles (the interpolations can be affine or non -affine). Examples with simple and more complex objects show how the technique can give results which correspond closely to the human notion of shape interpolation. The interpolations shown include some between a calf and a cow and between a cow and a giraffe. The examples given are in two dimensions, but all the steps except the segmentation have been implemented as well for three dimensional objects. W e also show the results of computation of distances between the objects used in our examples.  相似文献   
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建立带孔等厚薄壳荷重传感器弹性元件的优化参数模型、有限单元计算模型及优化数学模型,确定电阻应变计的粘贴位置,用结构分析软件ANSYS5.7及一阶优化方法优化弹性元件的形状,提高弹性元件在贴片位置的应变响应。  相似文献   
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