三角函数型增长曲线预测油田开发指标

提出了用三角函数表示的一类用于油田开发指标预测的增长曲线共6条，从而进一步完善和丰富了现有的增长曲线法。提出和推导了它们的Np-t、Qt-t、Qt-Np关系式、（Np/NRmax)Qtmax准数计算式以及参数求解式。其特片研究表明，它们特征相近；（Np/NRamx)Qtmax变化范围为0-0.36785，属于峰值产量出现在油田开发初期的情况，其Qt-Np关系为一不对称的拱形曲线。提出了求取曲线参数的过原点重复线性回归法。双河油田的实例表明该方法有一定实用价值。     

电容传感器在使用中存在的几个问题及处理方法

随着电容测量技术的迅速发展，电容传感器在非电量测量和自动检测中得到广泛应用，但它在使用过程中也存在一些问题，针对在使用电容传感器过程中存在的几个问题，从电容传感器的原理和工作过程两个方面进行了讨论，并提出行之有效的处理方法。     

环境敏感因素对电站正常蓄水位选择的影响

卜寺沟水电站预可阶段正常蓄水位是考虑规划成果、地形、地质务件、梯级衔接、水库淹没、筑坝技术、水能资源利用等因素综合初选的.从理论角度分析,水库淹没时水库内寺庙的影响,按全部淹没进行经济补偿处理代价较小;其社会环境敏感因素对正常蓄水位的选择不应起决定性作用.但是,考虑到少数民族群众、僧侣和地方政府的要求,适当降低正常蓄水位,以减少对扎西日岗寺庙的影响,将带来较积极的社会影响.     

Temperament in Childhood Predicts Body Mass in Adulthood: The Cardiovascular Risk in Young Finns Study.

This study examined associations of temperament at ages 6 to 12 with body-mass index (BMI) and waist circumference (WC) at ages 24 to 30 years. The participants were 619 men and women derived from the population-based Cardiovascular Risk in Young Finns Study. Temperament was operationalized as (negative) emotionality, sociability, and activity. High emotionality predicted increased BMI, independently of WC, and independently of childhood and adulthood risk factors for adult obesity. None of the temperament dimensions had any associations with WC after controlling for BMI. The findings suggest that temperamental difficulty in childhood may be a useful risk indicator for general body mass in adulthood, and the mechanisms relating temperament with body mass should be further explored. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

关于沥青针入度指数

介绍了沥青针入度指数(PI)的由来和计算、使用意义、局限性和分析。     

基于TMS320VC54X的实时卫星信号跟踪系统

介绍了一种在移动载体上实现卫星信号实时跟踪的系统设计方案，该方法以TMS320VC54X为核心信号处理芯片，利用姿态敏感元件稳定运动中的卫星接收天线，以使其始终对准所要跟踪的同步卫星，文章给出了这种方法的硬件原理和主要的软件设计思路。     

塔顶放大器在工程设计中的应用探讨

塔顶放大器在移动通信领域有较为广泛的应用，它通过降低(改善)等效接收噪声系数，从而提高上行接收灵敏度。本文将简要介绍塔顶放大器的应用和提高接收机灵敏度的计算。     

Optimization of support positions to maximize the fundamental frequency of structures

In this paper, the position optimization of simple supports is implemented to maximize the fundamental frequency of a beam or plate structure. Both elastic and rigid supports are taken into account. First, the frequency sensitivity with respect to the movement of a simple support is derived using the discrete method. By means of the shape functions of the finite element method, closed‐form sensitivity formulations are developed straightforwardly. Then, a heuristic approach, called evolutionary shift method, is presented for optimizing support positions with a fixed grid mesh scheme. Based on the design sensitivity analysis, the support with the highest efficiency is shifted in priority along the elementary edges with the interval (step) of the elementary size. To facilitate the convergence of the process, the interpolation technique is employed to evaluate the solution more accurately. Finally, three numerical examples are presented to demonstrate the validity of the sensitivity analysis and the effectiveness of the optimization method. Copyright © 2004 John Wiley & Sons, Ltd.