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91.
本文阐述了高品级金刚石富晶区动态生长原理与工艺的新进展,介绍了以优质、高产为双重目标的合成棒结构优化设计专利技术,并且探讨了片状触媒进一步减薄的可行性. 相似文献
92.
In this paper, we consider the problem of enumerating all maximal motifs in an input string for the class of repeated motifs
with wild cards. A maximal motif is such a representative motif that is not properly contained in any larger motifs with the
same location lists. Although the enumeration problem for maximal motifs with wild cards has been studied in Parida et al.
(2001), Pisanti et al. (2003) and Pelfrêne et al. (2003), its output-polynomial time computability has been still open. The
main result of this paper is a polynomial space polynomial delay algorithm for the maximal motif enumeration problem for the
repeated motifs with wild cards. This algorithm enumerates all maximal motifs in an input string of length n in O(n
3) time per motif with O(n) space, in particular O(n
3) delay. The key of the algorithm is depth-first search on a tree-shaped search route over all maximal motifs based on a technique
called prefix-preserving closure extension. We also show an exponential lower bound and a succinctness result on the number
of maximal motifs, which indicate the limit of a straightforward approach. The results of the computational experiments show
that our algorithm can be applicable to huge string data such as genome data in practice, and does not take large additional
computational cost compared to usual frequent motif mining algorithms.
This work is done during the Hiroki Arimura’s visit in LIRIS, University Claude-Bernard Lyon 1, France. 相似文献
93.
94.
在温和的条件下,通过Na2MoO4.H2O,FeC l3.6H2O及羟基乙叉二膦酸反应,得到了有机二膦酸配位的杂多钼酸盐Na7[Fe{Mo2O6CH3C(O)(PO3)2}2].23H2O,用X射线单晶衍射法和元素分析法确定了其结构,晶胞参数为:空间群P1,a=0.9524(11)nm,b=1.1056(13)nm,c=1.1508(13)nm,α=83.184(15)°,β=86.866(17)°,γ=83.247(17),°V=1.194(2)nm3,Z=1,R1=0.0397,wR2=0.0624(I>2σ).聚阴离子[Fe{Mo2O6CH3C(O)(PO3)2}2]7-为中心对称结构,两个碎片[Mo2O6{CH3C(O)(PO3)2}]5-被一六配位的过渡金属离子Fe3 连接,该聚阴离子具有C2h对称性. 相似文献
95.
J. Leslie Glick 《Accountability in research》2013,20(2-3):187-195
A survey was conducted in order to evaluate the responses of biotechnology executives concerning their perceptions of the frequency of questionable R & D studies performed in their companies and to assess the extent to which their companies voluntarily conducted data audits. Data audit was found to be commonly practiced on a voluntary basis by biotechnology companies, in contrast to its almost lack of practice by universities. However, public companies were more likely to practice data auditing than privately held companies. Moreover, the likelihood that managers suspected or detected questionable studies in their companies was significantly increased if the company practiced data auditing. 相似文献
96.
Knut Anton Mork 《商业与经济统计学杂志》2013,31(2):165-175
Revisions of the early GNP estimates may contain elements of measurement errors as well as forecast errors. These types of error behave differently but need to satisfy a common set of criteria for well-behavedness. This article tests these criteria for U.S. GNP revisions. The tests are similar to tests of rationality and are based on the generalized method of moments estimator. The flash, 15-day, and 45-day estimates are found to be ill behaved, but the 75-day estimate satisfies the criteria for well-behavedness. 相似文献
97.
J. Denis Sargan 《Econometric Reviews》2001,20(2):171-186
This paper examines the choice of critical values for testing both non-sequential and nested sequential sets of constraints in the standard linear regression model. Modest increases in (e.g.) t-ratio critical values relative to their one-off values are often sufficient to maintain proper size. A Bayesian decision-theoretic approach, highlighted by the Schwarz (1978) criterion, provides a framework for deriving consistency and asymptotic local power properties of both forms of testing (data mining) algorithms. 相似文献
98.
Mithilesh Mishra 《Comparative American Studies》2014,12(1-2):114-122
The paper shows how ‘America’ gradually became present in the Religious Circles of India after the arrival of Swami Vivekananda in America in 1893. Swami Vivekananda is the first individual who not only succeeded in introducing Hinduism, Vedanta in particular, to America and the West, but also in introducing what he considered to be the best aspects of American scientific and material culture to India. The bridge which Swami Vivekananda built and opened between America and India continues to be travelled by the saints, mystics, and religious leaders of India and the philanthropists, spiritual seekers and scholars of religion of America and the West even today. This modern re-synthesis of the material and the scientific with the Vedanta has been beneficial to both countries and cultures. 相似文献
99.
由于数码相机存储容量的限制,导致不同批次拍摄的照片命名相同而出现照片管理问题。利用GD I+提供的关于位图操作的类,实现照片EX IF信息的提取并根据提取信息重命名照片,方便了数码照片的管理。 相似文献
100.