RF CMOS body-effect circuits

After a theoretical and analytical study of the body effect in MOS transistors, this paper offers two useful models of this parasitic phenomenon. Thanks to these models, a design methodology, which takes advantage of the bulk terminal, allows to turn this well-known body-effect drawback into an analog advantage, giving thus an efficient alternative to overcome the design constraints of the CMOS VLSI wireless mass market. To illustrate the approach, four RF building blocks are presented. First, a 0.9 V 10 dB gain LNA, covering a frequency range 1.8-2.4 GHz, thanks to a body-effect common mode feedback, is detailed. Secondly, a body-effect linearity controlled pre-power amplifier is presented exhibiting a 5 dB m input compression point (ICP1) variation under 1.8 V power supply for half the current consumption. Lastly, two mixers based on body-effect mixing are presented, which achieve a 10 dB conversion gain under 1.4 V for a −52 dB LO-to-RF isolation. Well suited for low-power/low-voltage applications, these circuits implemented in a 0.18 μm CMOS VLSI technology are dedicated to multi-standard architectures and system-on-chip implementations.     

八周有氧锻炼的效果评价--体育锻炼对女大学生身体自我和生活满意度的影响

身体自我是指个体对自己身体的认知和评价,是对自己身体范围内各方面要素的能力感觉。通过体育锻炼,身体自我概念的某几个方面会产生较大的变化,但并不是所有变量都发生变化的。体育锻炼对女大学生身体自我会产生一定的影响,对于改善她们的生活满意度有积极的作用。     

浅谈综合布线系统接地设计

综合布线系统作为建筑智能化不可缺少的基础设施，其接地系统的好坏将直接影响到综合布线系统的运行质量，故而显得尤为重要。本文介绍了综合布线系统接地的结构及设计要求，并提出在接地设计中应注意的几个问题．     

工程机械液压柱塞泵使用与维修新探

本文以直轴斜盘式柱塞泵为例，介绍关于工程机械液压柱塞泵使用与维修的几种新的方法。     

电力变压器的动稳定

在变压器短路电动力的计算中,目前是以静态力代替动态力的方法来进行的。这不能适应变压器机械强度的要求。针对此问题,从电动力的基本理论出发,建立起变压器的动态数学模型,对变压器在短路电流作用下线圈产生的动态力进行了理论分析和计算,对在短路电流作用下的变压器线圈(器身)绝缘结构进行了初步研究,提出了动稳定的计算方法。     

Multimouth surfaces for synthetic actor animation

Most parts of the human body are cylindrical in shape. Generalized cylinders, with two cross-sectional openings, are a logical choice to represent these cylindrical shapes. However, a variety of human body regions can be visualized as surfaces with multiple openings or multimouth (MM) surfaces. Some examples of such surfaces are the pelvis, the chest, and the palms of the hands. We investigated the suitability of non-uniform rational B-spline (NURBS) formulation for creating multimouth surfaces. Two techniques, the surface wrapping model and the garland model, are presented.     

The evaluation of underarm deodorants

Double-blind cross-over trials in which trained assessors evaluated axillary malodour on a 0 to 10 scale showed that ethanol at 60% and 99% w/w significantly reduced odour for up to 24 h. Reduction in odour was increased by the addition of non-volatile antimicrobial ingredients such as chlorhexidine, Irgasan DP 300 (Triclosan, Ciba Geigy) or aluminium chlorhydrate.
Volunteer panellists were able to identify statistically significant deodorant effects when they rated their own axillary odour on a 0 to 10 scale.
An odour absorber, zinc ricinoleate (Grillocin, Grillo-Werke, A. G.) was used to treat existing malodour and gave reduced perception of that malodour for up to 24 h.
A close correlation was found between panel odour scores and the bacterial status of the axilla as assessed by the replipad technique when biocidal systems were studied. Irgasan DP 300, a bacteriostat, did not perform so well in skin flora sampling procedures, but was nevertheless effective as a deodorant ingredient. Thus in vivo microbiological techniques, although often useful as predictors of deodorancy, do not replace the carefully controlled clinical trial with direct assessment of odour.
L'evaluation de l'odeur des aisselles     

混合配置的PLC在邯钢7#高炉热风炉自动控制系统中的应用

本文简介了邯钢7#高炉热风炉的工艺状况，重点描述了基于Quantum PLC的热风炉本体仪控系统、基于西门子S7-400PLC（软件配置按PCS7系统模式）的热风炉热油预热控制系统和基于西门子S7与S5系列PLC混合配置的热风炉换炉电控系统的构成、软硬件配置、工作原理、主要控制功能和应用效果。     

脉冲平面波斜入射旋转对称体时域电磁散射特性分析

介绍了一种运用旋转对称时域有限差分算法进行电磁散射问题分析的方法。对脉冲平面波在圆柱坐标系下进行分解,应用总场/散射场连接边界引入入射波,采用PML吸收边界条件。运用这种方法分析了有限长度闭合金属圆柱体的散射问题,通过与矩量法分析结果的比较,验证了该方法的正确有效性。     

Integrated Simulation of Machine Tool and Process Interaction for Turning

The interaction between process and machine tool behaviour can lead to process instabilities in terms of self‐excited vibrations where the energy of the machine tool oscillation is generated by process excitation. The regenerative chatter effects lead to wavy surfaces on the work‐piece. This effect has been simulated for turning processes with an integrated simulation approach, which couples a time domain simulation model for the machine tool and the workpiece with an analytical turning model. In this paper a procedure is illustrated for coupling an FEA‐based 3‐dimensional turning model with the time domain model for the machine tool under consideration of the resulting workpiece surface. In comparison to an analytical approach for calculating the mechanical tool load, the 3D‐FEA‐model has the potential to determine the resulting cutting forces for even complex‐shaped tool geometries, e.g. a complicated chip breaker or a varying cutting edge radius on the main or minor cutting edge. As a matter of the huge model size the calculation time in particular for 3‐dimensional problems is comparatively long to analytical cutting force models. Therefore, in this paper an approach to reduce the calculation time by using characteristic diagrams for the calculated process forces in the FEA‐model is presented. The research has also been focused on the current major problem in the FEA‐based modelling that the thrust and feed forces are generally underestimated in the simulation.