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971.
本文讨论多变量非线性贝叶斯动态模型参数估计 ,将 Monte Carlo最优法用于极大似然函数 ,得到未知参数和状态变量的估计  相似文献   
972.
The parallel computational complexity of the quadratic map is studied. A parallel algorithm is described that generates typical pseudotrajectories of length t in a time that scales as log t and increases slowly in the accuracy demanded of the pseudotrajectory. Long pseudotrajectories are created in parallel by putting together many short pseudotrajectories; Monte Carlo procedures are used to eliminate the discontinuities between these short pseudotrajectories and then suitably randomize the resulting long pseudotrajectory. Numerical simulations are presented that show the scaling properties of the parallel algorithm. The existence of the fast parallel algorithm provides a way to formalize the intuitive notion that chaotic systems do not generate complex histories.  相似文献   
973.
A new method for handling correlation problems is described. The multivariate auto- and cross-correlation method allows the calculation of relationships between two functions including one or several variables with respect to changes in time or distance. Two applications from environmental analytical chemistry demonstrate the advantages of the method. Transport rates of heavy metals in river water can easily be measured and sampling procedures for suspended dusts can be rationalized.  相似文献   
974.
水煤浆作为经济型清洁燃料引起了人们的长期关注.水煤浆偏置射流预燃室具有对浆种适应性强,稳燃性能好等特点.本文对偏置射流预燃室稳定燃烧水煤浆的原理进行了探讨,并对该燃烧技术用于处理造纸黑液的研究情况作了介绍.结果表明,采用低压多级雾化喷嘴对水煤浆进行雾化,形成的雾炬和偏置射流预燃室的流场有良好的匹配,在预燃室内形成大尺度的回流区,有利于水煤浆的点火、稳燃和消除灰渣.  相似文献   
975.
The fast Fourier transform (FFT) sampling algorithm has been used with success in application to protein‐protein docking and for protein mapping, the latter docking a variety of small organic molecules for the identification of binding hot spots on the target protein. Here we explore the local rather than global usage of the FFT sampling approach in docking applications. If the global FFT based search yields a near‐native cluster of docked structures for a protein complex, then focused resampling of the cluster generally leads to a substantial increase in the number of conformations close to the native structure. In protein mapping, focused resampling of the selected hot spot regions generally reveals further hot spots that, while not as strong as the primary hot spots, also contribute to ligand binding. The detection of additional ligand binding regions is shown by the improved overlap between hot spots and bound ligands. © 2016 Wiley Periodicals, Inc.  相似文献   
976.
用低杂波鉴相器对相位测量系统各通道经进行了相位校准,得到了各通道的相位电压关系曲线,并进行了线性拟合,线性拟合误差小于3°;推导出了相位电压关系表达式,与校准得到的相位电压曲线相比平均误差小于0.7°。该系统已成功用于HL-2A装置低杂波实验,对4支速调管的输出相位进行了测量,并得到了放电过程中相位随阴极高压波动的曲线,得出了阴极电压波动2.2%引起相位波动13.8°的结论。  相似文献   
977.
Loop closure in proteins requires computing the values of the inverse kinematics (IK) map for a backbone fragment with 2n > or = 6 torsional degrees of freedom (dofs). It occurs in a variety of contexts, e.g., structure determination from electron-density maps, loop insertion in homology-based structure prediction, backbone tweaking for protein energy minimization, and the study of protein mobility in folded states. The first part of this paper analyzes the global structure of the IK map for a fragment of protein backbone with 6 torsional dofs for a slightly idealized kinematic model, called the canonical model. This model, which assumes that every two consecutive torsional bonds C(alpha)--C and N--C(alpha) are exactly parallel, makes it possible to separately compute the inverse orientation map and the inverse position map. The singularities of both maps and their images, the critical sets, respectively, decompose SO(3) x R(3) into open regions where the number of IK solutions is constant. This decomposition leads to a constructive proof of the existence of a region in R(3) x SO(3) where the IK of the 6-dof fragment attains its theoretical maximum of 16 solutions. The second part of this paper extends this analysis to study fragments with more than 6 torsional dofs. It describes an efficient recursive algorithm to sample IK solutions for such fragments, by identifying the feasible range of each successive torsional dof. A numerical homotopy algorithm is then used to deform the IK solutions for a canonical fragment into solutions for a noncanonical fragment. Computational results for fragments ranging from 8 to 30 dofs are presented.  相似文献   
978.
Capillary electrophoresis (CE) is a powerful separation tool for non-targeted analysis of chemically complex samples, such as blood, urine, and tissue. However, traditionally CE requires samples in solution for analysis, which limits information on analyte distribution and heterogeneity in tissue. The recent development of surface sampling CE–mass spectrometry (SS-CE–MS) brings these advantages of CE to solid samples and enables chemical mapping directly from the tissue surface without laborious sample preparation. Here, we describe developments of SS-CE–MS to increase reproducibility and stability for metabolite, lipid, and protein extraction from tissue sections and dried blood spots. Additionally, we report the first electrokinetic sequential sample injection for high throughput analysis. We foresee that the wide molecular coverage from a distinct tissue region in combination with higher throughput will provide novel information on biological function and dysfunction.  相似文献   
979.
980.
用总体幸福感量表对淮安市职业女性进行抽样调查,得到结论,年龄、婚姻状况、教育程度、月收入、健康状况、工作满意度、心理健康自评及家庭地位自评等都对职业女性的心理健康产生影响.所以,建议在有条件的情况下,应对民企及事业单位女性职工、30-40岁及50岁以上职业女性、高学历职业女性、低收入职业女性、身体不健康、工作满意度不高及对家庭地位满意度低的职业女性等的心理健康给予关注.  相似文献   
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