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101.
一阶非线性泛函微分方程的振动准则 总被引:6,自引:0,他引:6
研究两类带强迫项的一阶非线性泛函微分方程的振动准则,所得结果推广了已有文献的结果. 相似文献
102.
对“古文”“古文字”“古汉字”这一组汉字学术语的使用情况进行了分析和辨别,并在此基础之上分别给这几个术语进行了定义,希望能够有助于消除以往的一些错误认识,正确地使用相关术语。 相似文献
103.
决定热传导方程源项的一个正则化策略 总被引:1,自引:0,他引:1
确定热传导方程中的线性源项是一类有重要应用背景的反问题,它在Hadamard意义是不适定的,讨论了获得其稳定数值解的计算方法,给出一种新的离散正则化策略.理论分析与数值试验结果表明给出的算法是稳定和有效的. 相似文献
104.
QIANQuan GENGHuan-tong WANGXu-fa 《武汉大学学报:自然科学英文版》2004,9(5):765-769
This paper introduces the cost sensitive feature weighting strategy and its application in intrusion detection. Cost factors and cost matrix are proposed to demonstrate the misclassification cost for IDS. How to get the whole minimal risk. is mainly discussed in this paper in detail. From experiments, it shows that although decision cost based weight learning exists somewhat attack miselassifieation, it can achieve relatively low misclassification costs on the basis of keeping relatively high rate of recognition precision. 相似文献
105.
Michel Godet 《Journal of forecasting》1982,1(3):293-301
Although‘La Prospective’is not well known in the Anglo-Saxon forecasting literature, it has been for many years widely used in France and other Latin countries with considerable success. Lately, because of the inaccuracy of forecasting and the large forecasting errors that have been experienced, it is suggested that the Prospective approach can be used as a way of dealing with these problems. The main characteristics of‘La Prospective’are that it does not look at the future as a continuation of the past but rather as the outcome of the wishes of various actors and the constraints imposed on them by the environment. Its purpose is to assist in creating alternative futures and then select some alternative that allows for maximum freedom of action. 相似文献
106.
Calcineurin (CN) is thought to play a role in the synaptic plastivity and long-term potentiation (LTP) in the hippocampus.
Based on two LTP models in vivo, a specific inhibitor cyclosporin A (CsA) of CN was observed, which affected LTP in the hippocampal dentate gyrus of the
rats. The results indicated that CsA blocked LTP induced by high frequency stimulation (HFS) partly, but it had no effect
on the decrease of the onset and peak latency of population spikes (PS) except that it reduced the increase of the amplitude
after HFS. On the other hand, CsA blocked LTP induced by ginsenosides (GSS) completely. It suppressed the GSS-enhanced amplitude
of PS reversibly and blocked the decrease of the peak latency of PS induced by the GSS. These results suggest that the postsynaptic
CN plays a role in the induction of LTP in the hippocampus of the rats. 相似文献
107.
从等价电子组态的"自旋因式化"出发,导出了nsN~nhN组态的Lα、Lβ取值规则,给出了推求等价电子组态光谱项的简易方法. 相似文献
108.
医学微生物学存在一些科技术语的汉译名称不统一。文章就沙门氏菌属、耶尔森氏菌属、埃希氏菌属、志贺氏菌属、奈瑟氏菌属、布鲁氏菌属、克雷伯氏菌属、立克次氏体属、芽孢杆菌属、枝原体属等菌属名称,肥达氏试验、革兰氏染色、革兰氏阳性菌、细菌芽孢、非典型性肺炎和SARS、“病原生物学”等微生物学术语,进行了研讨和提议。 相似文献
109.
The delayed release of the National Account data for GDP is an impediment to the early understanding of the economic situation. In the short run, this information gap may be at least partially eliminated by bridge models (BM) which exploit the information content of timely updated monthly indicators. In this paper we examine the forecasting ability of BM for GDP growth in the G7 countries and compare their performance to that of univariate and multivariate statistical benchmark models. We run four alternative one‐quarter‐ahead forecasting experiments to assess BM performance in situations as close as possible to the actual forecasting activity. BM are estimated for GDP both for single countries (USA, Japan, Germany, France, UK, Italy and Canada), and area‐wide (G7, European Union, and Euro area). BM forecasting ability is always superior to that of benchmark models, provided that at least some monthly indicator data are available over the forecasting horizon. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
110.
Jinwang LIU Dongmei LI Xiaosong CHEN 《系统科学与复杂性》2007,20(4):610-613
Polynomial composition is the operation of replacing variables in a polynomial with other polynomials. λ-Grgbner basis is an especial Grobner basis. The main problem in the paper is: when does composition commute with λ-Grobner basis computation? We shall answer better the above question. This has a natural application in the computation of λ-Grobner bases. 相似文献