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71.
两点边值问题Daubechies小波δ-序列数值解法 总被引:1,自引:0,他引:1
使用广义函数δ-序列方法数值求解两点边值问题.这种δ-序列以Daubechies小波为基础,具有紧支、对称、拟插值的性质.以对流占优方程为例,空间导数采用Daubechies小波δ-序列作数值格式离散,验证了该方法的有效性.使用Daubechies小波δ-序列数值方法求解两点边值问题,方法简单,能方便地处理各类边值问题,计算精度高.数值算例表明,Daubechies小波δ-序列数值方法不仅能够较好地求解具有边界层的两点边值问题,而且可以非常方便地求解具有较高阶导数的梁、板等力学问题. 相似文献
72.
动态环境下基于势场原理的避障方法 总被引:3,自引:0,他引:3
在保留传统人工势场法原理简单、易于实现优点的基础上,对其应用在具有移动障碍物的动态环境中所表现出的缺陷进行了改进,用碰撞时间参数代替相对位置参数并辅以碰撞角度约束来消除无渭的避碰运动,同时又引入障碍物作用于机器人、方向指向目标点的分力和局部波动函数,较好地解决了因局部最小以及障碍物与目标点相距太近造成的不能成功到达目标点的问题.仿真结果表明此方法能够使机器人在具有静态和移动障碍物的复杂环境中安全避障. 相似文献
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Kai Zhao Xingyu Zhao Yaping Tu Qi Miao Dongxu Cao Wenjuan Duan Yang Sun Jincheng Wang Taotao Wei Fuyu Yang 《Cellular and molecular life sciences : CMLS》2010,67(15):2665-2678
We have reported that chymotrypsin B (CtrB) is not just a digestive enzyme but is also stored in lysosomes. Herein, we demonstrated a broad distribution of CtrB and explored the involvement of CtrB in apoptosis. Exposure of RH-35 cells to H2O2 or palmitate induced the redistribution of lysosomal CtrB into the cytoplasm as a result of lysosomal membrane permeabilization (LMP). Suppression of CtrB significantly blocked apoptosis, while overexpression of CtrB sensitized apoptosis markedly. CtrB could cleave Bid under neutral conditions. In RH-35 cells with Bid silenced, apoptosis induced by CtrB protein was attenuated, suggesting that CtrB mediates apoptosis of RH-35 cells mainly through processing Bid. Our data also suggest that LMP occurs earlier than mitochondrial outer membrane permeabilization; Bid activation initiated by caspase-8 might be reinforced by CtrB in consequence of LMP, which causes a positive feedback loop leading to the accumulation of tBid, and results in lysosome- and mitochondrion-dependent apoptosis. 相似文献
75.
本文用发散思维方法于无机化学教学过程,从不同的方向,不同的侧面,不同的层次,横向拓展,纵向深入,将学生的思维积极引向探索创新,克服思维定势,激发思维潜能,有助于学生全面把握相关知识点的相互联系和创新能力的提高。 相似文献
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王洁 《高技术通讯(英文版)》2009,15(2):203-207
Accurate performance prediction of Grid workflow activities can help Grid schedulers map activities to appropriate Grid sites.This paper describes an approach based on features-ranked RBF neural network to predict the performance of Grid workflow activities.Experimental results for two kinds of real world Grid workflow activities are presented to show effectiveness of our approach. 相似文献
78.
结合当前国内煤炭市场形势及国家煤炭企业综改政策,对新时期煤炭企业矿山管理的安全管理和经营管理等方面提出了创新性思考和可行性建议。 相似文献
79.
Collaborative Filtering (CF) is a commonly used technique in recommendation systems. It can promote items of interest to a target user from a large selection of available items. It is divided into two broad classes: memory-based algorithms and model-based algorithms. The latter requires some time to build a model but recommends online items quickly, while the former is time-consuming but does not require pre-building time. Considering the shortcomings of the two types of algorithms, we propose a novel Community-based User domain Collaborative Recommendation Algorithm (CUCRA). The idea comes from the fact that recommendations are usually made by users with similar preferences. The first step is to build a user-user social network based on users’ preference data. The second step is to find communities with similar user preferences using a community detective algorithm. Finally, items are recommended to users by applying collaborative filtering on communities. Because we recommend items to users in communities instead of to an entire social network, the method has perfect online performance. Applying this method to a collaborative tagging system, experimental results show that the recommendation accuracy of CUCRA is relatively good, and the online time-complexity reduces to O.n/. 相似文献
80.
This paper surveys the new field of programming methodology and techniques for future quantum computers, including design of sequential and concurrent quantum programming languages, their semantics and implementations. Several verification methods for quantum programs and communication protocols are also reviewed. The potential applications of programming techniques and related formal methods in quantum engineering are pointed out. 相似文献