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1.
Abundant researches approve that the bank-lending channel is the main monetary transmission channel in China recent years. But the most of investigations only focus on the behavior of the gross bank-lending index in the monetary transmission, and the further investigation hasn't been carried on. This paper divides the gross index of bank lending into the short-term and mid-, long-term loans based on the internal and external researches. It analyzes how the financial institutions adjust their lending policy under the impact of the monetary policy of the central bank and the effect of the adjustments on the macroeconomic, making the further study of the bank-lending channel in monetary transmission in China.  相似文献   

2.
For the shortage of tracking ability against fast fading channel of the existing pilot structures and channel estimation algorithms in OFDM combined with time division multiplexing (OFDM/TDM) system, an improved channel estimation algorithm is proposed. The channel transfer functions are obtained by estimating the channel properties with two adjacent time domain multiplexing (TDM) pilot sequences, while the channel state information of the OFDM/TDM symbols is obtained with interpolation Combined with frequency domain equalization based on minimum mean square error (MMSE-FDE), the proposed algorithm can significantly compensate the path loss over fast fading channels. Simulation results show that, compared with the existing channel estimation algorithms, the proposed algorithm can achieve better performance, which is not only capable of dealing with slow fading channels, but also has a better tracking ability against fast fading channels with the same data transmission efficiency.  相似文献   

3.
This paper employs vector autoregressive (VAR) models to measure the impact of monetary policy shocks on regional output in Indonesia. We find substantial cross‐regional variation in policy responses in terms of both magnitude as well as timing. Our work adds to the existing literature by providing insights from a large developing country, viz. Indonesia, where monetary policy has both a national and a regional dimension. The results support previous findings that the differential regional effects of monetary policy are significantly related to sectoral composition (especially the share of manufacturing), providing evidence for the relevance of the interest rate channel of monetary policy. We also find that firm size contributes to these differences, providing evidence for the importance of the credit channel. As a whole, both types of channels appear to operate simultaneously in the decentralized Indonesian monetary policy and to impact on the real part of the regional economy.  相似文献   

4.
The paper deals with the statistical characterization of mobile satellite channel, and introduces a statistical channel model-the Shadowing Rician Fading model for frequency nonselective land mobile satellite channel. The parameters contained in the model are given by means of trial and error. Based on the model, the BER(Bit Error Ratio)performance is analyzed for narrow-band modulation and wide-band spread -spectrum modulation of coherent PSK (Phase Shift Keying) signals. The results show that the multipath and fading phenomenon in the channels worsens the system bit error performance, while the use of wide band spread spectrum modulation can improve it efficiently. In addition, an analytical expression is derived for the irreducible probability of bit error of coherent PSK signals due to phase variations caused by fading and shadowing. At last, the numerical results are obtained and discussed.  相似文献   

5.
An analysis of the influence of channel on signal transmission in the wired measurcments-while-drilling ( MWD ) system is made. The cases of reflection and refraction to the signal at connecting points of wires are analysed. The transmitting channel must consist of many sections of wires in this measuring system. A few noteworthy practical problems arc put forward when designing this message-transmitting channel.  相似文献   

6.
A method of spatio-temporal channel assignment based on graph decomposition was proposed to solve the ripple effect and link failure problem in multi-radio wireless mesh networks. Network topology was decomposed into subgraphs in several time slots to extend channel assignment from spatial domain to time domain. Then, graph coloring algorithm was used to optimize the channel assignment on the basis of the subgraph in each time slot. Each subgraph obtained channel resource dynamically according to the network constraints to improve the channel assignment efficiency. Simulation results show that, compared to static channel assignment scheme, the impact of negative factors, such as the ripple effect and link failure caused by channel switching, are effectively confined with this strategy. The network throughput is increased at least by 30% while satisfying the constraints on the number of radios and the number of network channels.  相似文献   

7.
为了使得钢结构的性能与用钢量比达到最优,前人对槽型钢的截面尺寸优化进行了较为充分的研究。但是,涉及卷边角度的优化特别是偏心受压工况下的优化分析却很缺乏。以Yao-Teng偏心受压计算公式,结合遗传算法,以冷弯卷边槽钢柱偏心受压为例,将槽钢卷边角度与偏心距作为设计变量,寻找在不同偏心距受压情况下,达到最大畸变屈曲临界应力的卷边角度。基于有限条分析程序,对两端简支与两端固支情况下不同截面尺寸构件的畸变屈曲临界应力进行了计算分析,最终得出不同偏心距受压下统一的最优卷边角度。为了方便工程设计人员设计时参考,建议卷边角度统一取为100°。  相似文献   

8.
谢小丹 《中国农学通报》2009,25(19):309-313
本文通过对闽西北烟-稻轮作区2005-2007年度农田渠道建设中采用的浆砌石、预制混凝土渠槽、现场浇筑混凝土等三种防渗衬砌结构的渠道造价进行分析,结合防渗效果、工程效益、运行情况和使用年限等方面的比较,选择出造价经济、建设质量容易控制、防渗水效果好、工程效益高、运行情况好、使用年限长的现场浇筑混凝土结构作为渠道衬砌的主要方式。由于在现场浇筑混凝土的施工中采用了双面立模、钢架固定的立模新工艺,从而达到整体浇筑、一次成型的施工目的。实践证明此方法增强了渠道的密实度和强度,渠面麻点少、糙率减小,提高了防淤抗冲性、抗磨性,渠道线条更加流畅,美观度好,从而增加了过水能力,方便了管护运行,延长了渠道的使用年限。  相似文献   

9.
Tests are carried out on the filtration and organized forms of pure water flow and pond water flow using two kinds of flow channel porous ceramic membrane. Results show that for the two kinds of porous ceramic membranes, their removal efficiency of turbidity degree, chroma, CODMn and UV254 are nearly the same. The filtering quality of fan-channel porous ceramic membrane is better than that of circular-channel porous ceramic membrane, and the filtration flux of the former is 1.45 times the flux of the latter.  相似文献   

10.
为了探索生产商利润最大化目标下有限货源在线上线下渠道的数量配置方法,针对农产品双渠道供应链的鲜度竞争冲突,构建了双渠道货源配置函数,研究了有限供给下农产品生产商双渠道货源配置策略。结果表明:生产商将货源全部配置到线上渠道的主观意愿具有刚性,当生产商自己决定线上渠道鲜度时,线上线下渠道的初始配置量平均分配;当冷链物流服务商决定线上渠道鲜度时,线上渠道的初始配置为货源的3/4;在批发价高于一定阈值的条件下,生产商自己决定线上渠道鲜度,且把更多货源投向线下渠道,生产商的利润和系统利润均更高。  相似文献   

11.
2017年以来,江苏斑点叉尾鮰养殖规模急剧扩大,养殖面积已经达1万hm2,养殖产量也占全国总量的1/4。为了进一步推进江苏鮰鱼产业的稳定发展,文章从消费动态、苗种瓶颈、养殖模式和加工产业等方面概述了江苏斑点叉尾鮰产业现状,提出了产业面临的问题。随着沿海池塘养殖规模的大幅增加,江苏鮰鱼产业苗种和消费市场出现严重的供求不平衡,苗种和消费严重依赖省外,同时加工产品缺乏创新,消费形式单一。因此,研究提出良种良法结合,加强加工研发,建立品牌,拓宽销售渠道,以实现本省鮰鱼产业的可持续性发展。  相似文献   

12.
The aim of this article is to investigate the dynamic effects of monetary policy shocks on economic activity and aggregate price levels across Mexican states. To do this, a recursive structural panel VAR model is implemented as proposed by Pedroni which allows for regional heterogeneity and structural identifying restrictions of common monetary policy shocks. Empirical evidence suggests a common monetary policy shock to short‐term interest rates induces significant cross‐state variation in prices and output level responses. Additional analysis indicates that structural features, such as the industry mix and the small versus large firm mix, are possible sources of the observed cross‐state variation influenced by interest rates and credit channels. We conclude that the observed differentiated regional impacts are sufficiently important to justify rethinking Mexico's current monetary policy framework in order to explicitly consider a regional view.  相似文献   

13.
农业生态系统是一个半自然半人工的复合生态系统,受人类的活动影响较大。在我国的农业生产活动中,渠道化农田水利建设的推广和应用,引起了一系列的农业生态环境问题。本文采用现场调查、野外实验和实验室检测分析的方法,通过:(1)渠道对其不同距离(远、中、近)土壤速效养分的影响;(2)不同类别渠道对其内水样养分含量的影响;(3)不同类别渠道对其所在生境生物多样性的影响;三个方面进行研究。主要研究结果如下:(1)渠道所在区域土壤铵态氮及硝态氮呈现一致的季节性变化特征,即夏高冬低,而有效磷呈无规律性;渠道周边土壤铵态氮含量:中>远≈近;硝态氮为:近<中<远(2) 渠道的形态结构对生物多样性有显著的影响,各渠道动植物种类均呈现特征为:土渠>水泥渠。土渠对生境的影响较小,并且还有较好的“生物廊道”作用,有利于保持农业生态系统的物质及能量流动。(3)土渠对农业污染物净化能力明显高于水泥渠,通过对渠道内污染物含量的监测分析,土渠的截留净化效果优于水泥渠。  相似文献   

14.
Considering the interference introduced by primary user, the outage probability of cognitive relay networks under imperfect channel state information is analyzed based, on the relay selection for the maximum channel gain. In addition, the mathematical optimization model of maximizing the spectrum efficiency under the interference constraint of primary user and the QoS requirement of cognitive user is proposed for cognitive relay networks. Then, the optimal solution of the model is obtained with the Lagrangian method. The proposed scheme improves the spectrum efficiency of cognitive relay networks on the premise of guaranteeing the transmission performance of primary user. Simulation results show that the proposed power allocation scheme improves the system performance compared with the traditional equal power allocation scheme. Meanwhile, it indicates that the approximate spectrum efficiency can be obtained under the perfect channel state and the imperfect channel state. Under the imperfect channel state, the feedback information and the complexity of implementation will be reduced, which is beneficial to the engineering application.  相似文献   

15.
为了研究青海湖流域河道变化对湿地生态系统的影响,通过对青海湖流域5 条主要河流上中下游河道断面土壤及植被调查,结合水文和裸鲤监测数据,分析青海湖流域河道变化和湿地生态系统特点。研究结果表明:由于人类不合理的水土资源开发,湿地生态系统面临前所未有的挑战和压力。近年来,由于河流上游坡面侵蚀、中游阶地沟蚀河岸垮塌以及下游水利引水灌溉工程的影响,使得河道阻塞,河流改道或断流时有发生,最直接影响是阻断裸鲤回溯产卵通道,威胁青海湖湿地生态系统的稳定和安全。提出改善青海湖流域河道过水条件,保障青海湖流域湿地生态系统稳定和安全的对策措施。  相似文献   

16.
Using N-S function, and transforming the gravity item to temperature and differential pressure related items, the authors simulate the mixed convection heat transfer in vertical narrow rectangular channels. The results reveal that intense chimney effect exists in cross-section of the whole field and nearby the wall of the channel, When flow is laminar, the velocity of main flow will be decreased, disturbing nearby the heating wall is strengthened, and the convection heat transfer of vertical narrow rectangular channel is enhanced. It also can destroy the uniformity of the heat transfer coefficient distribution. Considering the reliability of equipment, this kind of convection pattern only can be used in low heat flux. The buoyancy-influencing model putted forward can predict mixed convection heat transfer, and also can be used to simulate the turbulent mixed-convection heat transfer problem.  相似文献   

17.
The energy consumption and sight pollution of glazing curtain wall are two problems to be urgently managed. Intelligent curtain wall is a new type one of energy conservation and environment protection, in which the thermal channel to save building energy consumption and automatic sunshade to adjust sunlight are adopted. Four engineering examples of oversea intelligent curtain wall are briefed. The construction and energy saving principle of ventilative curtain wall as the core technique of intelligent curtain wall are presented. The earliest ventilative curtain wall in China Mainland, and its test results of heat preservation in winter are stressed. The design experience of how to choose three key parameters: the width of thermal channel, the layout of inlet and outlet and the type of glass is discussed.  相似文献   

18.
A novel channel estimation algorithm is proposed for MB OFDM Ultra Wide Band systems based on tap detecting by exploiting the sparse property of channel impulse response. The channel parameters are estimated using the DFT algorithm based on cyclic convolution property of the receive signals. The nonzero taps are detected by exploiting the matching pursuit(MP) algorithm. The new estimated channel parameters are obtained by forcing the zero taps to zeros. Simulation results demonstrate that it has better MSE (mean square error) performance for the four channels proposed by IEEE. Especially for CM1 and CM2 channels, the performance of the algorithm has been greatly improved.  相似文献   

19.
林烟草钾离子通道基因NKT6的克隆与表达定位分析   总被引:3,自引:0,他引:3  
Shaker家族钾离子通道在植物钾的吸收转运及其他生命过程中发挥重要作用。本研究利用同源克隆的策略从林烟草中获得一个Shaker家族钾离子通道基因,命名为NKT6 (GenBank登录号为KC310448)。该基因cDNA序列全长2 317 bp,编码由681个氨基酸组成的蛋白,该蛋白与Shaker家族其他成员具有较高同源性。NKT6基因组CDS序列共含有11个外显子、10个内含子。系统进化树分析表明,NKT6蛋白是Shaker家族Group II的成员之一。荧光定量PCR分析发现,NKT6的表达量在林烟草的茎和腋芽中最高,在萼片、叶、花中其次,在根中最低。亚细胞定位结果表明,NKT6主要定位于细胞膜和核膜附近的内质网上。干旱与外源ABA胁迫处理下,NKT6的表达量均呈下降趋势。推测NKT6可能在林烟草气孔开放中发挥作用。  相似文献   

20.
The society-economy-environment appraisal for construction project can help our government to control macro-economy, make correlation policy and formulate laws and draw up city plan.It has great influence on the sustainable development of our society and it is the demand of the law for the environment evaluation in China.This paper introduced the basic structure of society-economy-environment appraisal system for construction project and the thought of elements transaction.Using the method of AHP, the model of project analyzing and optimizing selection is designed.For the more, the methods of the optimizing models on the selected schemes are put forward.Finally, the integrative analysis has been made on the system design and appliance of this appraisal system.  相似文献   

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