Primal or dual: which promises faster spatiotemporal search?

The existing predictive spatiotemporal indexes can be classified into two categories, depending on whether they are based on the primal or dual methodology. Although we have gained considerable empirical knowledge about various access methods, currently there is only limited understanding on the theoretical characteristics of the two methodologies. In fact, the experimental results in different papers even contradict each other, regarding the relative superiority of the primal and dual techniques. This paper presents a careful study on the query performance of general primal and dual indexes, and reveals important insight into the behavior of each technique. In particular, we mathematically establish the conditions that determine the superiority of each methodology, and provide rigorous justification for well-known observations that have not been properly explained in the literature. Our analytical findings also resolve the contradiction in the experiments of previous work.     

Effects of age and gender on maximum voluntary range of motion of the upper body joints

The maximum voluntary range of motion (ROM) of the major joints of the upper body was studied in a seated position and compared between young and elderly subjects. A total of 41 subjects (22 young male and female subjects aged 25 to 35 years, 19 elderly male and female subjects aged 65 to 80 years) took part in the experiment. In total, 13 maximum voluntary joint motions were performed by each subject. Age was found to have a non-uniform effect on the ROM of the joints investigated in this study. Its effect on ROM was joint specific and motion specific. The highest loss in ROM was observed in the neck and trunk, especially for neck extension, lateral flexion and axial rotation as well as for trunk lateral flexion and axial rotation. No significant age differences were observed in the elbow and wrist joint ROMs. The effect of gender on joint ROM was much weaker than that of age. Only four among the 26 joint ROMs investigated in this study were significantly different between the two gender groups.     

Modeling of a scanning laser range sensor for robotic applications

The geometric and noise modeling of a scanning range sensor is described. The parameters of the model are determined from data collected during the calibration of the real sensor. The models are shown to predict range scan results which accurately match those of the real sensor.     

基于RANPLAN iBuildNet的Small Cell Range Expansion仿真

首先介绍异构网络的背景及组成,然后结合iBuidNet软件对Small Cell流量分流与Range Expansion功能进行详细介绍,最后通过软件实现对LTE系统异构网络的Cell Range Expansion功能的仿真,说明iBuidNet软件在HetNet网络部署中的有效性。     

LTE-A系统时域小区间干扰协诟技术标准化研究

异构网络被LTE-A系统视为一种提升单位区域频谱效率的关键技术而得到广泛关注。然而,异构网络会带来严重的小区间干扰,小区间干扰协调因此成为3GPP标准化进程研究的重点。首先总结了异构网络及小区间干扰协调技术,然后介绍了目前3GPP中讨论的小区覆盖扩展（CRE：CellRange Extension）和基于几乎空白子帧（ABS：Almost Blank Subframe）的时域小区间干扰协调技术。最后,基于动态系统级仿真平台,评估了CRE和ABS技术方案系统性能。     

Research on performance influence of direct-path signal for DVB-S based passive radar

Passive radar detects moving targets by Cross Ambiguity Function (CAF), which is based on the cross correlation process of the direct-path signal in reference channel and echo signal in receive channel. Thus, the performance of direct-path signal is important to system performance for this type of radar. While the Signal to Noise Ratio (SNR) of direct-path signal is low, it will deteriorate the detection performance. In this paper, how SNR of direct-path signal induces degradation on the SNR of CAF, and how the integration gain affects by integration time are analyzed, both with theoretical analysis and numerical simulation, which are valuable for the R&D of passive radar.     

Some critical areas in robotics research

The general field of robotics is briefly reviewed. Two important areas—computer vision and compliance—are identified and discussed at some length. Some comparisons between the various approaches to the vision question are made, and active and passive force measurement are contrasted. Finally some other important areas including hierarchical control, manipulators, grippers and fixture are considered. It is concluded that significant developments in robotic technology, particularly as they apply to batch manufacturing, will be forthcoming in the near future.     

DESIGN AND EXPERIMENT OF ELECTRIC BUS

0 INTRODUCTION*Human being has waked up to come to face with more and more serious environmental pollution and energy crisis，decrease of emission and fuel consumption of automobile have been paid special attention. Electric vehicles have become focus because they have the advantages of vehicles using internal combustion engines in terms of zero emission，usage of alternative energy source and lower noise. More and more countries including China convoked their researchers and invested cap…     

面向DSRC的5.8GHz射频功率放大器仿真设计

基于winHBT工艺,利用ADS软件实现了用于DSRC系统5.8GHzRFPA的仿真设计,电路采用自适应线性化偏置电路,为核心电路提供了补偿电流和补偿电压。根据二端口网络S参数和Loadpull技术完成了功率放大器的匹配网络设计。最后在Cadence环境下完成了功放的版图设计。     

阿尔塔什水利枢纽工程的防雷设计与探讨

每年中国因雷电造成的事故层出不穷,在水电站投运后,雷击所产生的巨大电流对设备及人身造成的伤害不可逆转,严重情况下甚至会造成机组停机,大面积停电,从而影响人民的生产生活.为了方便后续阿尔塔什水利枢纽工程防直击雷的设计,本文通过对电站避雷针及避雷线的设置及联合保护范围的研究,最终确定防雷方案,运用了"图形"代替"公式"的计...