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91.
This applied study attempted to evaluate a combination of transfer procedures commonly used to teach tacts to children with autism. A receptive to echoic to tact transfer and an echoic to tact transfer procedure were combined during 5-min instructional sessions to teach tacts to a seven-year-old vocal child with autism. A multiple baseline design across three sets of ten tacts was used. Without the teaching procedure, the child acquired no target tacts. With the 5-min teaching procedure implemented first with Set 1 then with Sets 2 and 3, respectively, the child acquired thirty new tacts over sixty teaching sessions. The results have wide application for children with and without autism who need instruction to learn tacts. 相似文献
92.
变性蛋白质与正常对照组的蛋白质的HPLC-MS谱图存在人工无法发现的差异性,也是本文所说的特征,本文的研究工作就是通过信息学的方法寻找这些特征。实际工作中,我们先从谱图中提取数据,重新采样,并且对采样数据进行基线校正,归一化,噪声降解,得到预处理好的数据集。然后利用遗传算法来最优化结果,找到了变性蛋白质的特征谱线。我们期望根据这些特征建立未知蛋白质的分类模型,为疾病的诊断提供依据。 相似文献
93.
利用一种带相位因子的经典屏蔽Coulomb势,采用经典分析方法对反氢原子的能级和光谱给出了预言性的描述,结果发现其能级与光谱同氢原子有较大区别。在反氢原子中主量子数n小于1的分数值且正电子由基态跃迁到激发态时才产生光谱,与氢原子发光机制正好相反。 相似文献
94.
本文将谱域导纳法推广应用于各向异性介质基片微带,通过详细的理论分析,导出了各向异性等效传输线的特性导纳公式,并考虑了导带厚度的影响,建立了各向异性介质基片平面传输线传播常数色散特性的计算机程序。用本文推导的结果进行数值计算,在2-18GHz内求得的蓝宝石微带色散曲线与文献[1]的结果吻合得很好。此外,本方法直接、简明、且计算量小、适用于各类微波平面传输线的分析。因而,其具有较大的工程实用价值。 相似文献
95.
本文用群论的方法,通过分子对称性的分析,讨论了硫酸根离子SO2-4在配合物中的配位方式,并与实验事实进行了比较,得到了满意的结果。 相似文献
96.
Female assembly workers reporting constant neck and shoulder pain, despite ergonomically acceptable working conditions, were interviewed. As a starting point in the interviews, the patients were asked to describe their general situation at work. Their reports were fed back and discussed with company management in a wider group meeting and resulted in an improvement in their attitudes to those workers. A climate of confidence and well-being was created, which the women experienced as genuine. The workers' report of pains improved dramatically and absence due to musculoskeletal disorders was reduced by more than 90% during the following year. 相似文献
97.
98.
Y. Maleki 《统计学通讯:理论与方法》2013,42(23):4983-5004
We study locally self-similar processes (LSSPs) in Silverman’s sense. By deriving the minimum mean-square optimal kernel within Cohen’s class counterpart of time–frequency representations, we obtain an optimal estimation for the scale invariant Wigner spectrum (SIWS) of Gaussian LSSPs. The class of estimators is completely characterized in terms of kernels, so the optimal kernel minimizes the mean-square error of the estimation. We obtain the SIWS estimation for two cases: global and local, where in the local case, the kernel is allowed to vary with time and frequency. We also introduce two generalizations of LSSPs: the locally self-similar chirp process and the multicomponent LSSP, and obtain their optimal kernels. Finally, the performance and accuracy of the estimation is studied via simulation. 相似文献
99.
Silvia Lopes 《统计学通讯:理论与方法》2013,42(10):2955-2967
100.
Consider the general linear model Y = Xβ + ? , where E[??'] = σ2I and rank of X is less than or equal to the number of columns of X. It is well known that the linear parametric function λ'β is estimable if and only if λ' is in the row space of X. This paper characterizes all orthogonal matrices P such that the row space of XP is equal to the row space of X, i.e. the estimability of λ'β is invariant under P. An additional property of these matrices is the invariance of the spectrum of the information matrix X'X. An application of the results is also given. 相似文献