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1.
As an extension to the singly truncated case, this article further examines a doubly truncated normal distribution. In this article, we consider both symmetric and asymmetric cases with two truncation points on the left and the right, and develop the tables of a truncated mean, a truncated variance, and a cumulative probability.  相似文献   
2.
CuantumFuse nano copper material has been used to assemble functional LED test boards and a small camera board with a 48 pad CMOS sensor quad-flat no-lead chip and a 10 in flexible electronics demo. Drop-in replacement of solder, by use of stencil printing and standard surface mount technology equipment, has been demonstrated. Applications in space and commercial systems are currently under consideration. The stable copper-nanoparticle paste has been examined and characterized by scanning electron microscopy and high-resolution transmission electron microscopy; this has shown that the joints are nanocrystalline but with substantial porosity. Assessment of reliability is expected to be complicated by this and by the effects of thermal and strain-enhanced coarsening of pores. Strength, creep, and fatigue properties were measured and results are discussed with reference to our understanding of solder reliability to assess the potential of this nano-copper based solder alternative.  相似文献   
3.
Recently, Underwater Wireless Sensor Networks (UWSNs) has witnessed significant attention from both academia and industries in research and development, due to the growing number of applications for wide range of purposes including commercial, scientific, environmental and military. Some of the major applications include pollution monitoring, tactical surveillance, tsunami warnings and offshore exploration. Efficient communication among sensors in UWSNs is a challenging task due to the harsh environments and peculiar characteristics of UWSNs. Therefore, design of routing protocol for efficient communication among sensors and sink is one of the fundamental research themes in UWSNs. In this context, this paper proposes a location-free Reliable and Energy efficient Pressure-Based Routing (RE-PBR) protocol for UWSNs. RE-PBR considers three parameters including link quality, depth and residual energy for balancing energy consumption and reliable data delivery. Specifically, link quality is estimated using triangle metric method. A light weight information acquisition algorithm is developed for efficient knowledge discovery of the network. Multi-metric data forwarding algorithm is designed based on route cost calculation which utilizes residual energy and link quality. Simulations are carried out in NS-2 with Aqua-Sim package to evaluate the performance of RE-PBR. The performance of the proposed protocol is compared with the stat-of-the-art techniques: DBR and EEDBR. The comprehensive performance evaluation attests the benefit of RE-PBR as compared to the state-of-the-art techniques in terms of network lifetime, energy consumption, end-to-end delay and packet delivery ratio.  相似文献   
4.
This paper presents an application of the spectral element method for the stability analysis of regenerative machine tool chatter models in milling operations. An extension of the spectral element method is introduced in order to handle the discontinuities in the cutting force in an efficient way. The efficiency of the method is demonstrated on some well-known machine tool chatter models taken from the literature. Efficiency is characterized by the computational time, the convergence of the stability boundaries, and the convergence of critical characteristic multipliers. Results show that compared to the most widespread methods in machining literature, the spectral element method provides significant improvements in computational time while maintaining high accuracy levels.  相似文献   
5.
Over the past few years, there has been a growing demand to develop efficient precision mechanisms for fine moving applications. Therefore, several piezoelectric driven mechanisms have been proposed for such applications. In this work an optimal synthesis of a four-bar mechanism with three PEAs is proposed. Two evolutionary multi-objective Genetic Algorithms (GAs) are formulated and applied; A Genetic Algorithm Synthesis method (GAS) is first used to obtain a synthesis solution for the mechanism regardless of power consumption. Then another Genetic Algorithm Minimum Power Synthesis method (GAMPS) is used to obtain the synthesis solution of minimum power consumption. For that purpose, the study performs simulation investigation of the aforementioned algorithms for each point along sinusoidal and kidney shaped paths of motion. Results show capability of both methods in obtaining a synthesis solution. However, GAMPS outperformed GAS in terms of driving power consumption as it is minimized by 99% ratio.  相似文献   
6.
Smoking is a risk factor for a variety of deleterious conditions, such as cancer, respiratory disease and cardiovascular disease. Thrombosis is an important and common aspect of several cardiovascular disease states, whose risk is known to be increased by both first- and secondhand smoke. More recently, the residual cigarette smoke that persists after someone has smoked (referred to as thirdhand smoke or THS) has been gaining more attention, since it has been shown that it also negatively affects health. Indeed, we have previously shown that 6-month exposure to THS increases the risk of thrombogenesis. However, neither the time-dependence of THS-induced thrombus formation, nor its sex dependence have been investigated. Thus, in the present study, we investigated these issues in the context of a shorter exposure to THS, specifically 3 months, in male and female mice. We show that the platelets from 3-month THS-exposed mice exhibited enhanced activation by agonists. Moreover, we also show that mice of both sexes exposed to THS have decreased tail bleeding as well as decreased thrombus occlusion time. In terms of the role of sex, intersex disparities in thrombus development and hemostasis as well as in platelet aggregation were, interestingly, observed. Together, our findings show that exposing mice to THS for 3 months is sufficient to predispose them to thrombosis; which seems to be driven, at least in part, by an increased activity in platelets, and that it does not manifest equally in both sexes.  相似文献   
7.
LTE/LTE-A networks have become widely exploited to address the increasing demands of mobile traffic. Relay technologies have recently been introduced to fulfill such requirements. Currently, the LTE-A relay standard is restricted to two-hop relaying. This architecture minimizes system complexity, but multi-hop relay architecture could potentially provide greater capacity and coverage in the future. However, many complexities of the multi-hop relaying paradigm must be resolved. In this work, we focus on downlink resource allocation and relay selection, by which a user may be connected to a base station through a multi-hop relay and have several relay stations from which to choose within his range. To overcome the additional challenges introduced by multi-hop relay nodes, we propose a dynamic joint resource allocation and relay selection scheme. Numerical results are presented to demonstrate the validity of the proposed algorithm.  相似文献   
8.
针对国内医院普遍存在预约机制不完善和医患矛盾突出引发的设备诊断依赖度高和病人等待时间长等问题,本研究特别考虑多医生同时诊断、设备检查以及病人设备检查后回诊等因素,建立普通门诊预约排程模型,在验证模型有效性的基础上,结合实际设计了六种排程规则并进行仿真研究,对提前预约与随机到达病人的比例、预约时间长度作了灵敏度分析,最后通过仿真实验找到相对较优的比例和预约时间值.  相似文献   
9.
A new system for sleep multistage level scoring by employing extracted features from twenty five polysomnographic recording is presented. For the new system, an adaptive neuro-fuzzy inference system (ANFIS) is developed for each sleep stage. Initially, three types of electrophysiological signals including electroencephalogram (EEG), electrooculogram (EOG), and electromyogram (EMG) were collected from twenty five healthy subjects. The input pattern used for training the ANFIS subsystem is a set of extracted features based on the entropy measure which characterize the recorded signals. Finally an output selection subsystem is utilized to provide the appropriate sleep stage according to the ANFIS stage subsystems outputs. The developed system was able to provide an acceptable estimation for six sleep stages with an average accuracy of about 76.43% which confirmed its ability for multistage sleep level scoring based on the extracted features from the EEG, EOG and EMG signals compared to other approaches.  相似文献   
10.
本文在推导固液两相流动边界层数学模型的基础上 ,采用泊松 (Poisson)方程来生成网格 ,使网格的生成得到较好的控制 ,同时对方程进行适体坐标变换并利用有限差分法对之进行离散求解。为固液两相流动的流场计算提供了一个可行的方法  相似文献   
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