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91.
Claus Bahlmann Author Vitae 《Pattern recognition》2006,39(1):115-125
The selection of valuable features is crucial in pattern recognition. In this paper we deal with the issue that part of features originate from directional instead of common linear data. Both for directional and linear data a theory for a statistical modeling exists. However, none of these theories gives an integrated solution to problems, where linear and directional variables are to be combined in a single, multivariate probability density function. We describe a general approach for a unified statistical modeling, given the constraint that variances of the circular variables are small. The method is practically evaluated in the context of our online handwriting recognition system frog on hand and the so-called tangent slope angle feature. Recognition results are compared with two alternative modeling approaches. The proposed solution gives significant improvements in recognition accuracy, computational speed and memory requirements. 相似文献
92.
Hiroshi Ohta Tomoyuki Hirota Abdur Rahim 《The International Journal of Advanced Manufacturing Technology》2007,33(1-2):36-41
This paper analyzes a multi-product production / inventory system where demands for each item arrive according to a Poisson
process and the production time for each product has an Erlang distribution. The paper proposes an optimality condition that
specifies whether each product should be produced make-to-stock or make-to-order. In the event a product should be produced
make-to-stock, an approach for computing the optimal base-stock level is proposed. Numerical examples are given for illustrative
purpose. 相似文献
93.
准噶尔盆地腹部普遍发育深层(大于4000m)超压系统,很多钻井都钻遇超压。通过对超压段钻井、地质、测井、地震特征系统研究发现,超压段泥浆密度大幅增加,具有高声波时差、低电阻率以及地震低速的超压响应特征。利用Dix公式计算地震层速度和利用Fillippone公式计算地层压力,得到超压数据体。准噶尔盆地腹部超压在白垩系及其以下沉积地层中均有分布,超压层的深度范围不同。分1井西凹陷边缘以及昌吉凹陷西南有空层现象。超压顶面分布的层位由北往南、从东到西逐渐变浅,从三叠系顶部到白垩系底部。深部超压对油气分布和富集有着重要的控制作用,准噶尔盆地腹部超压层分布的研究将对本区油气勘探起积极的推动作用。 相似文献
94.
当前水价改革中迫切需要注意的问题 总被引:5,自引:0,他引:5
加强水价改革,提高水价,促进节约用水,已经成为全社会关注的焦点。在节约用水和水资源优化配置条件下如何确定水价,水价构成及供水企业的合理成本与利润,以及资源水价的分配和用途是当前水价改革中亟须研究探讨和重视的问题。商品水价应该包括三个部分:一是资源水价,二是工程水价,三是环境水价。只有包括资源因素的水价,才能真正发挥水价在水资源的优化配置和合理利用方面的调节作用。 相似文献
95.
In the design process of the photocatalytic oxidation (PCO) reactor using TiO2-coated foam nickels, the optimum of catalyst film thickness, light intensity and flow velocity were considered. A model was developed to study the effect of catalyst film thickness on photocatalytic degradation of formaldehyde by a TiO2-coated foam nickel at continuous flow mode. In this model, external mass transfer and internal molecule diffusion-reaction were considered. A first-order kinetics equation was used to account for the photocatalytic reaction. Two exponential equations were employed to describe the distribution of light intensities in foam nickels and catalyst films, respectively. Validated with experimental data, the model can be used to predict the optimal thickness of catalyst films. A method for determining appropriate light intensities was proposed and discussed. The appropriate light intensity can be obtained by giving a margin, regarded as an excess coefficient, to the light intensity calculated based on the assumption of complete use of excited electron–hole pairs. The excess coefficient needs to be determined experimentally. In addition, the optimal flow velocity of PCO reactors could be consistent with the required one by changing the windward area of foam nickels. Based on the theoretical analyses, a novel PCO reactor containing 15 parallel-connected cells was designed. Each reaction cell was composed of an UV lamp and a TiO2-coated tubular foam nickel. The performance of the reactor was tested by degrading gaseous formaldehyde at an indoor concentration level. The results showed that the reactor had low pressure loss and good degradation capability. 相似文献
96.
本文探讨了高速钢在高温形变过程中碳化物析出的行为及奥氏体组织状态对析出的影响。用透射电镜和扫描电镜分析了不同热处理状态奥氏体的组织结构,分析了高温形变过程中碳化物析出的部位,颗粒尺寸及形态。试验表明, 碳化物主要在奥氏体的缺陷处呈点状和点列状析出,大小为20mμ。处于回复状态的奥氏体缺陷诱发碳化物析出,析出碳化物钉札缺陷阻止再结晶进行。当再结晶驱动力较大时,由于动态再结晶充分发展,使缺陷大量消除,碳化物析出显著地减少。 相似文献
97.
This paper presents Bayes estimators for the reliability measures of the individual components in a multi-component systems in the presence of masked system life test data. The life time distributions of the system components are assumed to be geometric with different parameters. Two-sided Bayesian probability intervals of the parameters are also derived. Numerical simulation study is given in order to: (i) explain how one can apply the theoretical results obtained, (ii) study the influence of the sample size and masking level on the accuracy of point estimates. 相似文献
98.
The main purpose of this paper is to find the mixed-mode stress intensity factors of composite materials using the crack opening displacement (COD). First, a series solution of the composite material with a crack was used to evaluate COD values. Then, the least-squares method was used to calculate mixed-mode stress intensity factors. This algorithm can be applied to any method that generates or measures COD values. The major advantage of this method is that COD values very near the crack tip are not necessary. Both finite element simulations and laboratory experiments were applied to validate this least-squares method with acceptable accuracy if the even terms of the series solution are removed. 相似文献
99.
李杏娟 《冶金标准化与质量》2003,41(5):45-48
论述了湘钢目前利用煤岩学数据指标判定进厂煤质情况,指导煤场分堆,优化配煤结构.同时在保证焦炭质量稳定的前提下,配入少量低灰的气煤,有效地提高了焦炭质量. 相似文献
100.
用激光粒度分析仪测定二氧化锆粒度 总被引:3,自引:0,他引:3
介绍以六偏磷酸钠作为分散剂,采用激光粒度分析仪测量二氧化锆粒度的一种新方法。该方法的测量范围为0.05~300μm。 相似文献