排序方式： 共有97条查询结果，搜索用时 15 毫秒
81.
运用1997至2006年我国投入产出数据进行分析,藉由天际图分析法及产业关联分析中之向前、向后关联效果及乘数积矩阵分析法,对我国产业结构的跨期变化及变迁趋势进行实证分析。研究表明,我国服务业对国内经济的影响力呈扩张趋势,而制造业的影响力则下降;初级加工业的生产资源正逐渐向高新技术产业或高附加值产业及高级化服务业部门转移;各产业关联程度差异有明显上升趋势,产业总需求矩阵依然存在不对称的产业关联程度关系;产业间相互影响效果差异增大,且相互影响程度呈上升趋势,尤其表现在非制造业中。 相似文献
82.
投资、出口和消费是拉动经济增长的三大动力,在出口和投资对经济增长的拉动作用乏力时,把注意力转向消费就成为必然。当前,我国经济面临的主要问题是消费需求不足,形成的原因在于消费周期的中断,收入分布的断层,社会保障体制不健全等。因互,通过高速消费信贷政策、增加居民收入,降低消费品价格等,以达到启动消费之目的。 相似文献
83.
首先提出了一个新的电流型跨导运算放大器(OTA)非线性多端口宏模型,该模型用构造法建立,可模拟差模、共模输入阻抗、共模抑制比、可变跨导等典型参数以及偏置电流的影响,并用简洁的电路,模拟了OTA的输入饱和特性,避免了复杂的公式推导及运算.通过计算机SPICE程序的模拟和实验,证实了该模型的正确性.作为OTA的应用,还在典型OTA乘法器基础上,用本模型设计并实现了双差动式乘法器,克服了典型OTA乘法器的不足,经过理论和实验分析,取得了很好的结果. 相似文献
84.
论我国投资乘数效应变动的趋势及原因 总被引：1，自引：0，他引：1
通过对近10年来我国投资乘数效应的变动趋势的分析,指出我国投资乘数的变化趋势是投资乘数较小并不断降低,且变化频繁。究其产生的深层原因主要是我国消费倾向低、资金沉淀以及投资消费周转壁垒过多等因素。通过对其原因的剖析,以期为我国经济政策的制订提供一定的理论依据。 相似文献
85.
通过选取适当的位称函数,同时利用拉格朗日乘子法给出了角点柱式支承矩形板弯曲问题有的内力及位移的计算公式,该法计算精度高,与前人方法相比,计算了过程简单。 相似文献
86.
The aim of this study was to investigate effects of speed and plane of motion on stability during locomotion in skilled football players. Ten male national-level football players participated in this study to run forward, backward and in lateral directions on a treadmill at 80%, 100% and 120% of their preferred running speeds. The coordinate data of passive reflective markers attached to body segments were recorded using motion capture systems. Time series data obtained from the ankle marker were used for further analyses. The largest finite-time Lyapunov exponent and maximum Floquet multiplier were adopted to quantify local and orbital dynamic stabilities, respectively. Results showed that speed did not significantly change local and orbital dynamic stabilities in any of running patterns. However, both local and orbital dynamic stability were significantly higher in the secondary plane of progression. Data revealed that in running, unlike walking, stability in the direction perpendicular to the direction of running is significantly higher, implying that less active control is required in the secondary plane of progression. The results of this study could be useful in sports training and rehabilitation programmes where development of fundamental exercise programmes that challenge both speed and the ability to maintain stability might produce a tangible enhancement of athletic skill level. 相似文献
87.
The sedimentation of a single circular particle between two parallel walls was studied by means of direct numerical simulation (DNS) and experiment. The improved implementation of distributed Lagrange multiplier/fictitious domain method used in our DNS is a promising new way for simulation of particulate flows. The settling behaviors of the particle are presented ranging in Reynolds number from 0 to about 700, which showed that our results for low Reynolds numbers agreed well with that reported before. Nevertheless, for higher Reynolds numbers our results were different from theirs. The long-term mean equilibrium positions in our results were all on the centerline, but not at off-center position as reported before. In order to validate our simulation, experiments were also conducted. The results showed that the sedimenting behavior simulated in this paper agreed well with our experiment result. 相似文献
88.
陈刚 《南通职业大学学报》2005,19(4):94-96
建立了两种税制下预算乘数计算的数学模型，着重分析了比率税制下政府收入增加量的涵义，阐述了平衡预算乘数对国民收入的作用。 相似文献
89.
高钦翔 《遵义师范学院学报》2002,4(1):74-75
从气体分子速率分布函数出发,同时考虑速度的大小和方向,利用拉格朗日未定乘子法导出气体分子按麦克斯韦速度分布规律;并利用简单的体积元转换得到气体分子按麦克斯韦速率分布率。 相似文献
90.
以同步检波器解调DSB、SSB信号为例,提出利用电子仿真软件Multisim8.0进行计算机虚拟仿真作为高频电子线路实验的辅助手段,阐述计算机虚拟仿真的效果和结果. 相似文献