查询词典 selective channel

Our research work concentrates on the severe communication circumstances, for example, spatially correlative and time-frequency selective fading channel, and focuses on the design of codec for space-time architecture and the utilizing of linear precoding technique especially on the multiuser scenario trying to improve the system performance to combate various fading.

论文首先基于已有空时相关MIMO信道模型，分析给出了联合空时互相关函数解析表达式，并推导给出了空时分组编码传输方案理论成对错误概率表达式。

The effects could be attributed to the selective action of BmK Ⅰ on the TTX-S Na〓 channel: slowing the inactivation process of Na〓 channel, increasing the amplitude of peak Na〓 currents; 2 BmK abT, a new-type neurotoxin with higher sequence homology to β-type scorpion neurotoxin, was found to slow the inactivation process of Na〓 channel and prolong the duration of action potential in DRG neurons.

这些结果提示BmK IT2和BmK AS-1的外周抗伤害性效应可能是通过它们对小直径DRG神经元外周游离末梢即C纤维末梢上的TTX-S和TTX-R钠通道的门控调节所致，且BmK IT2对角叉菜胶致炎大鼠较强的抗伤害性作用可能是由于它对TTX-R钠通道较高的敏感性所致。二。特异性钠通道调制剂-东亚钳蝎神经毒素的电生理特征。

Results from whole-cell patch clamp showed: 1 BmK Ⅰ(α-like neurotoxin) was found to prolong the duration of action potential and promote the amplitude of action potential. The effects could be attributed to the selective action of BmK Ⅰ on the TTX-S Na〓 channel: slowing the inactivation process of Na〓 channel, increasing the amplitude of peak Na〓 currents; 2 BmK abT, a new-type neurotoxin with higher sequence homology to β-type scorpion neurotoxin, was found to slow the inactivation process of Na〓 channel and prolong the duration of action potential in DRG neurons.

全细胞膜片钳研究发现：1）类α型哺乳动物毒素BmK Ⅰ可延长部分DRG神经元全细胞动作电位的时程，增加动作电位的幅度，这些效应可归咎于BmK Ⅰ选择性地作用于DRG神经元TTX—S钠通道，延缓TTX—S钠电流的失活化相，峰钠电流幅度增加；2）BmK abT，一个与β型毒素同源性较高的新型蝎毒素可抑制DRG神经元全细胞钠电流失活化过程，使动作电位时程增加。

In frequency selective fading channels, different channel has different fading, that is to say, different channel has different transmission quality.

在频率选择性衰落信道中，不同的子信道受到不同的衰落，也就是说有不同的传输质量。

By time-varying filtering, we realize the signal selectivity and interference suppression, especially for the signals with time-varying power spectrum. It is shown herein that conventional eigenstructure based methods are lower dimensional special case of the time-frequency subspace fitting method. The closed-form array response estimation algorithms for blind source separation in wireless communication is also developed in the dissertation by exploiting the data structure of second-order statistics of the array output in the presence of multipath. The proposed method achieves array response estimation with little constraint on signal property and propagation environment such as scatters or angular spread. Moreover, the array utilized here can be of arbitrary geometry and even uncalibrated. Since the closed-form solution is obtained, no misconvergency may occur and large amount of computation can be saved. The equivalent feed model and corresponding optimization designation are proposed to realize the downlink multi-user selective transmission. By coherent and non-coherent superposition of the electromagnetical field, multiple beams can be formed using a single array, so that each co-channel user signal is transmitted in each beam and will not interfered with each other. The proposed system scheme implements the digital beamforming and the channel allocation in the base band, therefore is suitable for the utilization of the radio software technology. The feasibility and effectiveness of the proposed model are proved by the RF experiment.

在窄带条件下，GSC－SSF方法还可以提高阵列的虚拟孔径，从而提高估计的性能；可以证明，Cyclic DOA 和SC-SSF方法可看作该方法的特例或近似； 3、提出了二维GSC－SSF方法和宽带谱相关DOA矩阵方法，利用信号的循环平稳特性解决了宽带条件下二维 DOA 估计问题，并具有阵元数少、计算量较小的特点； 4、提出了时频子空间拟合和宽带时频DOA估计算法，将联合时频分析的理论和方法引入到阵列信号的空间谱估计研究中，利用时变滤波实现信号选择性测向和干扰抑制，特别适合于谱时变信号；可以证明传统特征结构法可看作是时频子空间拟合方法的特例； 5、提出了多用户环境下阵列响应的估计方法——CARE方法，该方法对信号结构和传播参数（主要是散射源分布与角度散布）的约束较少，适用于各种几何结构的阵列甚至未校准的阵列，能够直接得到阵列响应的闭式解，因此计算量小、稳健性好，不存在收敛问题； 6、提出了针对多用户下行选择性发送的阵列等效激励模型、优化设计方法及其系统实现方案，通过空间场的相干叠加与非相干叠加使得单一阵列能够形成多个波束，并保证各波束内的用户信号各不相同且相互干扰最小；其系统方案具有在基带实现数字波束成形、信道分配并便于软件无线电实现的特点，其有效性已得到外场实测数据的证实。

Second, in this thesis we discuss how to make OFDM system combats with time selective channel.

当移动速度增加时，多普勒谱的四阶矩也增加，随之时间轴上的导频密度x_1应该减小。

RESULTS:(1) ET-1 could increase total protein production, surface area, ERKs activity and ［Ca2+］i in cultured cardiomyocyte in dose-dependent manner at concentrations ranging from 10-9 to 10-7 mol/L. And this effect could be abolished by BQ123, an antagonist of ETA receptor, partly inhibited by PTX, but not by BQ788, an antagonist of ETB receptor.（2）The activation of ERKs and the increase of ［Ca2+］i induced by ET-1 were obviously inhibited by PD98059, a selective ERKs kinase inhibitor, and nifedipine, a calcium channel blocker, respectively. Both antagonists partially inhibited ET-1-stimulated cardiomyocyte hypertrophic response.(3) Staurosporine, a selective PKC inhibitor, could inhibit ET-1-stimulated cardiomyocyte hypertrophic response and increase of ［Ca2+］i, but not affect the activation of ERKs.

结果： ①ET-1浓度依赖性增加新生大鼠心肌细胞蛋白质含量和心肌细胞表面积、ERKs活性及［Ca2+］i浓度，以上作用可被ETA受体拮抗剂BQ123所完全抑制，被百日咳毒素部分抑制，而ETB受体拮抗剂BQ788则无效；②ERKs激酶特异性抑制剂PD98059可完全抑制ET-1激活ERKs的作用，钙通道拮抗剂硝苯地平可明显抑制ET-1介导的［Ca2+］i浓度增加，但二者皆仅部分抑制ET-1介导的心肌细胞肥大反应；③蛋白激酶C选择性抑制剂staurosporine并不能明显抑制ET-1介导的ERKs激活，但可抑制ET-1介导的的［Ca2+］i浓度增加及心肌细胞肥大反应。

In wireless broadband digital communication, Inter-Symbol Interference caused by time disperse of radio channel is one of main factors that limit bandwidth of communicated information and system performance of communication. In receiver, Orthogonal Frequency Division Multiplexing system can easily cancel ISI and equalize frequency-selective fadings that are both caused by time disperse of radio channel.

在这一系统中，无线信道时延扩展引起的符号间干扰是限制传输性能和信息速率的主要因素之一；而在消除符号间干扰和均衡由无线信道时延扩展引起的频率选择性衰落方面，正交频分复用(Orthogonal Frequency Division Multiplexing，OFDM)技术具有明显优势。

Antinociception and VGSC-modulation of BmK IT2 and BmK AS—1. The results from nociceptive flexion reflex and plantar radiation heat showed: BmK IT2 (a depressant insect-selective neurotoixn) and BmK AS-1 (a new-type β-1ike neurotoxin) have significant antinociceptive effects on rat peripheral nerve system. The antinociceptive effects of BmK IT2 on the carrageenan-inflamed rats were significantly stronger than those on the normal rats. Whole-cell patch-clamping showed: Both TTX-S and TTX-R Na〓 currents induced from rat DRG neurons were significantly inhibited by BmK IT2 and BmK AS—1, and BmK IT2 was more sensitive to TTX-R than TTX-S component. All the results suggested: the peripheral antinociception of BmK IT2 and BmK AS—1 might be attributed to the inhibitory effects of them on the TTX-S and TTX-R Na〓 channel located on the peripheral ends of rat DRG neurons with small diameter.

中文题名特异性钠通道调制剂－长链蝎神经毒素的药理功能研究副题名外文题名 The study of pharmacological function of the specific modulators on voltage-gate Na+ channel-long chain scorpion neurotoxin 论文作者谭智勇导师吉永华研究员学科专业生理学研究领域\研究方向学位级别博士学位授予单位中国科学院上海生命科学研究院学位授予日期2002 论文页码总数93页关键词神经毒素毒理学电压门控钠通道东亚钳蝎钠通道调制剂馆藏号BSLW /2003 /R338 /22 本论文工作利用细胞和行为药理技术系统地研究了东亚钳蝎长链神经毒素的抗伤害性效应、对电压门控钠通道的电生理调制作用、改变胞内离子浓度的效应，并分析了相关的药理功能机制。

Channel throughput is improved through FEC, delayed acknowledgements with selective retransmissions and dynamic channel change.

通过FEC、有选择重发的滞后确认和动态信道变化，信道的吞吐量得到大大改进。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。