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101.
茹丽娟 《科技情报开发与经济》2012,22(13):110-112
数据采集技术是信息科学的一个重要分支,更是智能电网中一项重要的技术。设计出了一种具有8通道模拟量输入及开关量输入/输出、日历等功能的通用多路数据采集系统,采用的控制器的核心器件为TI公司的MSP430F149,指出该系统具有功耗低、体积小、易操作等优点。 相似文献
102.
This paper proposes a modified centralized shifted Rayleigh filter(MCSRF) algorithm for tracking boost phase of ballistic missile(BM) trajectory with a highly nonlinear dynamical model based on bearings-only.This paper contributes three folds.Firstly,the mathematical model of an MCSRF for multiple passive sensors is derived.Then,minimum entropy based onedimensional optimization search to adaptively adjust the probability of the different filters for real time state estimation is deployed.Finally,the unscented transform(UT) is introduced to resolve the asymmetric state estimation problem.Simulation results show that the proposed algorithm can consecutively track the BM precisely during the boost phase.In comparison with the unscented Kalman filter(UKF) algorithm,the proposed algorithm effectively reduces the tracking position and velocity root mean square(RMS) errors,which will make more sense for early precision interception. 相似文献
103.
建立了反周期函数的(0,δP)插值算子,得到了插值问题解的相关结论,是对(0,P(D))插值算子的一种推广. 相似文献
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106.
As the foundation of an industrialized country nowadays, machine tools industry is regarded as the engine of industrial development of a country. The developed countries, such as USA, Germany and Japan, have widely deployed the technology of using the patent in order to keep their strength in various fields. This research examins the CNC machine tools industry in the world by using the pa- tent analysis method. It first gives an overview about the world patent application in CNC machine tools industry from 1963 to 2010 and divides the development of the industry into five stages. It also lists the patent application of the world top 20 countries, where the top 5 countries are compared. The patents of the world top 10 companies of machine tools manufacturers are mapped according to the international patent classification (IPC), and the future trends of world machine tools industry are discussed. Finally conclusions and suggestions are presented. 相似文献
107.
3 GPP LTE has approved uplink intra-cell power control and defined overload indicator (OI) for uplink inter-cell power contrQ1 to mitigate the inter-cell interference (ICI), respectively. In this pa- per, we propose a hierarchical power control ( HPC ) scheme where intra-eell and inter-cell power controls interact with each other. The inter-cell power control eommand is generated by radio re- source management (RRM) entity according to the ICI-load model together with the current ICI and served load information. This ICI-load model is proposed as a guideline for coordination among cells to enable the system to approach its system specific interference over thermal noise (IoT) work area. Simulation results show that for HPC scheme, the system' s IoT is well controlled to fit its pre-de- fined work area and the power efficiency is improved significantly. Our proposed scheme is also ro- bust to different settings of its inter-cell power control period. 相似文献
108.
邱树艺 《福州大学学报(自然科学版)》1989,(1):82-88
本文应用壳体理论和有限条元法解周边缝拱坝的坝体变位与应力,导得坝体条元的刚度矩阵及等效结线荷载,编制了计算机程序和计算实例。 相似文献
109.
Myelin sheaths: glycoproteins involved in their formation,maintenance and degeneration 总被引:8,自引:0,他引:8
Quarles RH 《Cellular and molecular life sciences : CMLS》2002,59(11):1851-1871
Myelin sheaths are formed around axons by extending, biochemically modifying and spiraling plasma membranes of Schwann cells
in the peripheral nervous system (PNS) and oligodendrocytes in the central nervous system (CNS). Because glycoproteins are
prominent components of plasma membranes, it is not surprising that they have important roles in the formation, maintenance
and degeneration of myelin sheaths. The emphasis in this review is on four integral membrane glycoproteins. Two of them, protein
zero (P0) and peripheral myelin protein-22 (PMP-22), are components of compact PNS myelin. The other two are preferentially
localized in membranes of sheaths that are distinct from compact myelin. One is the myelin-associated glycoprotein, which
is localized at the inside of sheaths where it functions in glia-axon interactions in both the PNS and CNS. The other is the
myelin-oligodendrocyte glycoprotein, which is preferentially localized on the outside of CNS myelin sheaths and appears to
be an important target antigen in autoimmune demyelinating diseases such as multiple sclerosis.
Received 8 April 2002; received after revision 13 May 2002; accepted 22 May 2002 相似文献
110.
糖尿病肾病大鼠胰基因组DNA甲基化状态的变化 总被引:10,自引:0,他引:10
分别从正常大鼠、糖尿病肾病大鼠、中药糖微康治疗的糖尿病肾病大鼠 、西药开博通治疗的糖尿病肾病大鼠的胰组织中提取其基因组DNA,用对DNA甲基化作用敏感 的限制性核酸内切酶HpaⅡ和MspⅠ(为一组同裂酶)进行限制性酶切;并进行染色质DNaseⅠ敏感性分析. 实验发现中药糖微康治疗后能向正常方向逆转胰组织DNA中CCGG位点甲基化状态,胰组织中处于转录活性状态的染色质明显增加. 这表明中药糖微康能通过提高基因转录水平和向正常方向恢复甲基化状态而发挥其治疗作用. 相似文献