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31.
宋煜  周丽萍 《化学教育》2018,39(13):30-37
鉴于当前学生化学意志素质缺乏的问题,探讨以认知、情绪唤醒、情感、意志为主控目标,在预习、尝试学习、交错搭配合作学习中,开展CAFP教学研究,以促成情意因素对认知的调动、动力、强化等功能。  相似文献   
32.
In this paper we use fixed point and coincidence theorems due to Park [8] to give matching theorems concerning closed coverings of nonempty convex sets in a real topological vector space. Our new results extend previously given ones due to Ky Fan [2], [3], Shih [10], Shih and Tan [11], and Park [7].  相似文献   
33.
《中国化学快报》2020,31(12):3163-3167
The rapid identification of pathogens is crucial in controlling the food quality and safety. The proposed system for the rapid and label-free identification of pathogens is based on the principle of laser scattering from the bacterial microbes. The clinical prototype consists of three parts: the laser beam, photodetectors, and the data acquisition system. The bacterial testing sample was mixed with 10 mL distilled water and placed inside the machine chamber. When the bacterial microbes pass by the laser beam, the scattering of light occurs due to variation in size, shape, and morphology. Due to this reason, different types of pathogens show their unique light scattering patterns. The photo-detectors were arranged at the surroundings of the sample at different angles to collect the scattered light. The photodetectors convert the scattered light intensity into a voltage waveform. The waveform features were acquired by using the power spectral characteristics, and the dimensionality of extracted features was reduced by applying minimal-redundancy-maximal-relevance criterion (mRMR). A support vector machine (SVM) classifier was developed by training the selected power spectral features for the classification of three different bacterial microbes. The resulting average identification accuracies of E. faecalis, E. coli and S. aureus were 99%, 87%, and 94%, respectively. The overall experimental results yield a higher accuracy of 93.6%, indicating that the proposed device has the potential for label-free identification of pathogens with simplicity, rapidity, and cost-effectiveness.  相似文献   
34.
Is it true that every matching in the n-dimensional hypercube can be extended to a Gray code? More than two decades have passed since Ruskey and Savage asked this question and the problem still remains open. A solution is known only in some special cases, including perfect matchings or matchings of linear size. This article shows that the answer to the Ruskey–Savage problem is affirmative for every matching of size at most . The proof is based on an inductive construction that extends balanced matchings in the completion of the hypercube by edges of into a Hamilton cycle of . On the other hand, we show that for every there is a balanced matching in of size that cannot be extended in this way.  相似文献   
35.
Let M be a perfect matching in a graph. A subset S of M is said to be a forcing set of M, if M is the only perfect matching in the graph that contains S. The minimum size of a forcing set of M is called the forcing number of M. Pachter and Kim (1998) conjectured that the forcing number of every perfect matching in the n-dimensional hypercube is 2n?2, for all n2. This was revised by Riddle (2002), who conjectured that it is at least 2n?2, and proved it for all even n. We show that the revised conjecture holds for all n2. The proof is based on simple linear algebra.  相似文献   
36.
Kreweras conjectured that every perfect matching of a hypercube Qn for n2 can be extended to a hamiltonian cycle of Qn. Fink confirmed the conjecture to be true. It is more general to ask whether every perfect matching of Qn for n2 can be extended to two or more hamiltonian cycles of Qn. In this paper, we prove that every perfect matching of Qn for n4 can be extended to at least 22n?4 different hamiltonian cycles of Qn.  相似文献   
37.
Extraction of relevant lip features is of continuing interest in the visual speech domain. Using end-to-end feature extraction can produce good results, but at the cost of the results being difficult for humans to comprehend and relate to. We present a new, lightweight feature extraction approach, motivated by human-centric glimpse-based psychological research into facial barcodes, and demonstrate that these simple, easy to extract 3D geometric features (produced using Gabor-based image patches), can successfully be used for speech recognition with LSTM-based machine learning. This approach can successfully extract low dimensionality lip parameters with a minimum of processing. One key difference between using these Gabor-based features and using other features such as traditional DCT, or the current fashion for CNN features is that these are human-centric features that can be visualised and analysed by humans. This means that it is easier to explain and visualise the results. They can also be used for reliable speech recognition, as demonstrated using the Grid corpus. Results for overlapping speakers using our lightweight system gave a recognition rate of over 82%, which compares well to less explainable features in the literature.  相似文献   
38.
A graph G with at least 2m+2 vertices is said to be distance d m-extendable if, for any matching M of G with m edges in which the edges lie at distance at least d pairwise, there exists a perfect matching of G containing M. In this paper we prove that every 5-connected triangulation on the projective plane of even order is distance 3 7-extendable and distance 4 m-extendable for any m.  相似文献   
39.
40.
如何根据患者的差异化需求,撮合医生与患者双方形成合理有效的医疗服务供需匹配,是医疗服务运作管理中重要的研究问题。本文针对医疗服务中医生与患者的实际需求,提出了一种考虑患者预约行为的匹配决策方法。在该方法中,首先依据患者的预约行为及特征分类;然后,通过计算不同情形下医患双方的差异度,获得了医患双方的满意度矩阵;在此基础上,提出了匹配预约患者与医生的E-HR算法,并进一步构建了匹配剩余患者和医生的多目标优化模型,通过模型求解得到最优匹配结果;最后,通过算例说明了本文提出方法的可行性和实用性。  相似文献   
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