Reliability Estimation of Blu‐Ray Recordable Media with Effect of Initial Recording Performance

The lifetime and the reliability of Blu‐Ray Recordable media were estimated with an acceleration test varying the temperature and the relative humidity. Some brand of the media showed relatively long lifetime over 80 years, but another brand was immeasurable because the media was broken during the acceleration procedure. A strong dependence of the lifetime of the media on the brand was observed. Effect of the initial recording performance in terms of the random symbol error rate and the jitter on the reliability was analyzed. The random symbol error rate showed a strong correlation with the reliability of the Blu‐Ray Recordable media. Copyright © 2014 John Wiley & Sons, Ltd.     

Isochoric p-ρ-T Measurements on 1,1-Difluoroethane (R152a) from 158 to 400 K and 1,1,1-Trifluoroethane (R143a) from 166 to 400 K at Pressures to 35 MPa

The p--T relationships have been measured for 1,1-difluoroethane (R152a) and 1,1,1-trifluoroethane (R143a) by an isochoric method with gravimetric determinations of the amount of substance. Temperatures ranged from 158 to 400 K for R152a and from 166 to 400 K for R143a, while pressures were up to 35 MPa. Measurements were conducted on compressed liquid samples. Determinations of saturated liquid densities were made by extrapolating each isochore to the vapor pressure, and determining the temperature and density at the intersection. Published p--T data are in good agreement with this study. For the p--T apparatus, the uncertainty of the temperature is ±0.03 K, and for pressure it is ±0.01% at p>3 MPa and ±0.05% at p<3 MPa. The principal source of uncertainty is the cell volume (28.5 cm³), which has a standard uncertainty of ±0.003 cm³. When all components of experimental uncertainty are considered, the expanded relative uncertainty (with a coverage factor k=2 and thus a two-standard deviation estimate) of the density measurements is estimated to be ±0.05%.     

基于真实物体模型的空间对象检索技术研究

针对MBR模型只适合检索联通的空间对象且查准率较低的问题,建立了真实物体模型,依据空间对象在平面上的几何投影的方法建立真实物体模型,采用深度方向关系矩阵表示真实物体模型之间的方向关系,利用该模型可以很好地将矩形代数良好的计算性质应用于空间对象检索技术中,简化了检索的过程,实现了矩形代数与真实物体模型的有效结合,使其检索的范围变的更加广泛.同时提出了一种改进的R*树算法,有效地提高了真实物体模型的检索精确度,降低了错误匹配的发生率.实验结果表明,该算法可以有效地提高检索的查准率,提高空间对象检索的效率.     

A comparative study of two techniques for improving power‐handling capability of CMOS T/R switches

This article proposes an asymmetric topology for transmit/receive (T/R) switches and more importantly presents a comparative study of both LC‐tuned and resistive body‐floating techniques for improving the power‐handling capability of the T/R switches in the same 0.18‐μm triple‐well CMOS. It is shown from simulations and measurements that the switches adopting either technique achieve comparable performances. For instance, the switch employing the LC‐tuned body‐floating technique exhibits insertion loss of 1.5 dB, isolation of 23.5 dB, and power‐handling capability of 22.5 dBm at 5.2 GHz, whereas the switch using the resistive body‐floating technique exhibits insertion loss of 1.3 dB, isolation of 24 dB, and power‐handling capability of 22.2 dBm, respectively. Therefore, one can conclude that the asymmetric topology with the resistive body‐floating technique is more suitable for designing T/R switches for wireless local area network applications as it consumes smaller silicon area. © 2010 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2010.     

Output feedback control of linear fractional transformation systems subject to actuator saturation

In this paper, the control problem for a class of linear parameter varying (LPV) plant subject to actuator saturation is investigated. For the saturated LPV plant depending on the scheduling parameters in linear fractional transformation (LFT) fashion, a gain-scheduled output feedback controller in the LFT form is designed to guarantee the stability of the closed-loop LPV system and provide optimised disturbance/error attenuation performance. By using the congruent transformation, the synthesis condition is formulated as a convex optimisation problem in terms of a finite number of LMIs for which efficient optimisation techniques are available. The nonlinear inverted pendulum problem is employed to demonstrate the effectiveness of the proposed approach. Moreover, the comparison between our LPV saturated approach with an existing linear saturated method reveals the advantage of the LPV controller when handling nonlinear plants.     

Some fixed point theorems in 1-M-complete fuzzy metric-like spaces

Very recently, in order to unify the notions of fuzzy metric space and metric-like space, Shukla and Abbas introduced the concept of fuzzy metric-like space and proved some fixed-point results in this setting. In this article, we modify the notion of Cauchy sequence and completeness to generalize their results. Thus, we extend their theorems to a more general framework, which is also appropriate to generalize some recent, well-known results in this line of research. Furthermore, several examples are presented to illustrate the significance of our results.     

基于R型聚类-因子分析的指标体系简化方法

评价指标体系过于复杂,容易产生冗余信息,增加计算与分析的难度.本文针对评价指标体系的简化方法展开研究,提出了基于R型聚类-因子分析的代表元提取方法.该方法具有定量控制代表元的信息丢失率、代表元实际含义易于解释等优点,同时避免了因子分析难以处理独立指标的问题.实验结果表明本文所提出的R型聚类–因子分析指标体系简化方法可以在没有先验知识可用的情况下,有效提高指标体系的简明性与有效性,同时保持指标信息的完备性.     

基于RS、GIS集成的水深探测研究

利用陆地卫星TM影像反射率和实测水深值之间的相关性,建立了遥感信息与水深之间的非线性回归模型.给出了遥感图像去噪算法.在此基础上设计了一个基于GIS组件MapX,采用C/S架构,使用VB和Microsoft SQLServer 数据库相结合的集成系统,实现了水深探测的可视化以及水深信息的查询和管理功能.实验结果表明,改进模型预测精度高,系统具有可视化、集成化和可扩展性强等特点,能够满足水深探测研究的需要.