In this paper we propose a multiple feature approach for the normalization task which can map each disorder mention in the text to a unique unified medical language system（UMLS）concept unique identifier（CUI）. We d...In this paper we propose a multiple feature approach for the normalization task which can map each disorder mention in the text to a unique unified medical language system（UMLS）concept unique identifier（CUI）. We develop a two-step method to acquire a list of candidate CUIs and their associated preferred names using UMLS API and to choose the closest CUI by calculating the similarity between the input disorder mention and each candidate. The similarity calculation step is formulated as a classification problem and multiple features（string features,ranking features,similarity features,and contextual features） are used to normalize the disorder mentions. The results show that the multiple feature approach improves the accuracy of the normalization task from 32.99% to 67.08% compared with the Meta Map baseline.展开更多
The phase dependence and independence of the response of a trichromatieally driven two-level medium to an arbitrarily intense probe field have been studied. The sum of the relative phases of the sideband components of...The phase dependence and independence of the response of a trichromatieally driven two-level medium to an arbitrarily intense probe field have been studied. The sum of the relative phases of the sideband components of the trichromatic field compared to the central component plays a crucial role in the response of the medium. For a weak probe field, as the sum of the relative phases changes from 0 to π, multiple switching can be achieved, in which switching from normal to anomalous dispersion occurs in multiple separate frequency regimes. The remarkable dependence on the sum phase is also shown for a strong probe field. On the other hand, when the sum of the two relative phases is fixed, the changes in the respective phases have no influence on the response of the medium.展开更多
In this paper, we prove the following results： 1） A normal basis N over a finite field is equivalent to its dual basis if and only if the multiplication table of N is symmetric; 2） The normal basis N is self-dual i...In this paper, we prove the following results： 1） A normal basis N over a finite field is equivalent to its dual basis if and only if the multiplication table of N is symmetric; 2） The normal basis N is self-dual if and only if its multiplication table is symmetric and Tr（α^2） = 1, where α generates N; 3） An optimal normal basis N is self-dual if and only if N is a type-Ⅰ optimal normal basis with q = n = 2 or N is a type-Ⅱ optimal normal basis.展开更多
The non-uniformity effect of the inter-foil distance has been studied using a gaseous electron multiplication（GEM） detector with sensitive area of 50mm×50mm. A gradient of the inter-foil distance is introduced ...The non-uniformity effect of the inter-foil distance has been studied using a gaseous electron multiplication（GEM） detector with sensitive area of 50mm×50mm. A gradient of the inter-foil distance is introduced by using spacers with different heights at the two ends of the foil gap. While the cluster size and the intrinsic spatial resolution show insignificant dependence on the inter-foil distance, the gain exhibits an approximately linear dependence on the inter-foil distance. From the slope, a quantitative relationship between the change of the inter-foil distance and the change of the gain is derived, which can be used as a method to evaluate the non-uniformity of the foil gap in the application of large-area GEM detectors.展开更多
基金Supported by the National Natural Science Foundation of China(61133012,61202193,61373108)the Major Projects of the National Social Science Foundation of China(11&ZD189)+1 种基金the Chinese Postdoctoral Science Foundation(2013M540593,2014T70722)the Open Foundation of Shandong Key Laboratory of Language Resource Development and Application
文摘In this paper we propose a multiple feature approach for the normalization task which can map each disorder mention in the text to a unique unified medical language system（UMLS）concept unique identifier（CUI）. We develop a two-step method to acquire a list of candidate CUIs and their associated preferred names using UMLS API and to choose the closest CUI by calculating the similarity between the input disorder mention and each candidate. The similarity calculation step is formulated as a classification problem and multiple features（string features,ranking features,similarity features,and contextual features） are used to normalize the disorder mentions. The results show that the multiple feature approach improves the accuracy of the normalization task from 32.99% to 67.08% compared with the Meta Map baseline.
基金Project supported by the National Natural Science Foundation of China （Grant No 60378008）.
文摘The phase dependence and independence of the response of a trichromatieally driven two-level medium to an arbitrarily intense probe field have been studied. The sum of the relative phases of the sideband components of the trichromatic field compared to the central component plays a crucial role in the response of the medium. For a weak probe field, as the sum of the relative phases changes from 0 to π, multiple switching can be achieved, in which switching from normal to anomalous dispersion occurs in multiple separate frequency regimes. The remarkable dependence on the sum phase is also shown for a strong probe field. On the other hand, when the sum of the two relative phases is fixed, the changes in the respective phases have no influence on the response of the medium.
文摘In this paper, we prove the following results： 1） A normal basis N over a finite field is equivalent to its dual basis if and only if the multiplication table of N is symmetric; 2） The normal basis N is self-dual if and only if its multiplication table is symmetric and Tr（α^2） = 1, where α generates N; 3） An optimal normal basis N is self-dual if and only if N is a type-Ⅰ optimal normal basis with q = n = 2 or N is a type-Ⅱ optimal normal basis.
基金Supported by National Natural Science Foundation of China(11375094,U1332207,11120101004)by Tsinghua University Initiative Scientific Research Program
文摘The non-uniformity effect of the inter-foil distance has been studied using a gaseous electron multiplication（GEM） detector with sensitive area of 50mm×50mm. A gradient of the inter-foil distance is introduced by using spacers with different heights at the two ends of the foil gap. While the cluster size and the intrinsic spatial resolution show insignificant dependence on the inter-foil distance, the gain exhibits an approximately linear dependence on the inter-foil distance. From the slope, a quantitative relationship between the change of the inter-foil distance and the change of the gain is derived, which can be used as a method to evaluate the non-uniformity of the foil gap in the application of large-area GEM detectors.
