螺杆泵综合参数诊断系统软件设计

螺杆泵工况综合参数诊断系统是一种多参数测试系统，系统软件的设计要求是测试螺杆泵井的电压、套压、工作电流、电压、螺杆扭矩和转速，然后利用测量的参数对螺杆泵油油井的工况进行综合分析判断。     

一种地面驱动螺杆泵井工况诊断方法

随着地面驱动螺杆泵采油技术的推广应用,急需寻找一种方便直观判断油井工况的方法.根据螺杆泵工作特性,提出一种定性诊断工况方法,为合理调整螺杆泵工作参数提供科学依据.     

航天测量船工况设计的模糊综合评估方法

航天测量船工况设计是海上测控方案设计中最为重要也是最为复杂的一部分。文中提出了基于模糊理论的综合评判理论对各个测量船工况设计方案进行总体评估,运用层次分析法确定权重系数,最后对评估结果进行分析,为方案决策提供客观、量化的科学依据。     

扬声器综合参数CAT技术探讨

本文在对目前国内扬声器检测现状的分析基础上,提出应用CAT技术来改造扬声器的传统测试方式,提高检测效率和检测精度,并进行实验研究,按照GB9396—88《扬声器主要性能测量方法》,组建了CAT系统。文章根据实践阐述了实现扬声器CAT的基本思路、系统测量仪器配置以及程序测量方法,最后通过一组实验数据展示了系统运行效果。     

电子计算机热参数监护系统的设计

本文概述了电子计算机热参数监护系统设计的目的、任务内容和要求。     

三相交流电参数综合监测仪的设计

本文介绍了一种具有完整交流参数的三相监控器的设计,并讨论了系统的硬件组成,各功能部分的电路设计和系统的软件设计,给出了单片机的数据采集和分析处理方法等。     

基于实际工况和运行载荷的城市公交传动参数优化研究

针对实际运行工况与传动比参数不匹配导致公交车燃油经济性变差的问题,采集超过10万km的实车运行数据,从中提出了10个反映线路运行特点的特征参数,基于运动学片段构建了公交特征工况,与实际路况统计特征参数相对偏差在3%以内。采用拉丁超立方抽样的试验设计方法,以发动机工况点在万有特性MAP经济区域分布比例最大为优化目标,建立基于工况和载荷状态的GT整车性能仿真模型,以动力性设计指标为约束条件,确定最佳的传动比参数。结果表明,基于运行工况和实际载荷优化公交车传动比参数,实现车辆燃油经济性改善是可行的,油耗比原车降低了2.76%。     

综合布线系统（二）：第二讲 综合布线系统的网络结构,布线部件和指标参数

概述了综合布线系统的网络结构和主要布线部件等基本内容;较全面地介绍了综合布线系统的信道和链路;说明了各段缆线的最大长度;系统列出了对绞线和对绞电缆布线链路和光缆布线链路的性能指标和主要参数。     

浅谈综合布线

本文简要介绍综合布线的标准和评测的参数，并阐明了与综合布线有关的几个概念的辨别及如何选择综合布线系统。     

综合工艺参数对常用钢铁材料的激光淬火特性的影响

本文利用CO2边疆激光器对HT200和45钢进行了表面淬火。对淬硬层显微组织、硬度和深度进行了研究，发现综合工艺参数（q）对材料的激光淬火有较强的影响规律。     

螺杆式与模块化地(水)源热泵机组技术经济比较

对螺杆式地(水)源热泵机组和模块化地(水)源热泵机组进行了详细的技术经济比较,使人们更进一步认识到模块化地(水)源热泵机组的优越性。     

Optimal Synthesis of Distributed Parameter Systems

A technique is developed for the synthesis and design of a distributed parameter system guiding waves from one point in space to another. The parameter distributions are assumed to be nonrestricted except for the upper and lower bounds resulting from the imposition of physical realizability. The problem is similar to the "sensitivity" problem encountered in the optimal control of the systems. An improved version of the first-order gradient technique is used to obtain the optimal distributions of the parameters. The first-order gradient technique is sensitive to the form of the arbitrary distributions assumed at the start of the iterations. This technique has serious convergence problems associated with it. The problem is particularly severe and is encountered in "singular" optimal control problems. The algorithm devised here improves the first-order gradient technique so that it becomes less sensitive to the initial assumed distributions and virtually eliminates the convergence problems generated because of the bounds on the parameter distributions. A transmission line with distributed series r, l and shunt c is a particular case of the distributed parameter system. The optimal design of a notched filter employing a thin film circuit is a successful example of the application of the improved gradient technique. These distributions have been obtained by the use of a hybrid computer.     

基于多模型参数估计的舵机故障诊断算法

为了实现无人机舵机工作状态的在线监测,实时提供故障类型与故障程度,设计了一种基于多模型参数估计的舵机故障诊断算法。首先描述了舵机各典型故障类型的动态特性,并建立相应的故障模型。然后就各故障类型设计相应的故障状态观测器及参数估计器,实时监测舵机运行状态,在舵机出现故障时能够及时给出故障信息。同时设计多观测器切换机制,以解决多个观测器的选取问题。仿真结果表明,建立的故障模型能够很好地描述典型故障的动态特性,多观测器切换机制能够及时准确地切换至最接近当前舵机状态的观测器,给出最接近实际情况的故障信息。     

Strong Tracking Filter-Based Fault Diagnosis of Networked Control System with Multiple Packet Dropouts and Parameter Perturbations

This paper mainly discusses the fault diagnosis problem for a class of nonlinear dynamic discrete systems with parameter perturbations and network-induced packet dropouts based on a recursive strong tracking filter. Due to the limited network bandwidth, the data transmitted via the Internet from different sensors may suffer from independent packet dropouts. And then, a series of Bernoulli sequences is employed to simulate the multiple data loss rates. In the residual design process, for a strong tacking filter (STF) which appears as an enhanced extended Kalman filter by introducing a fading factor in the filter structure, both parameter perturbations and packet dropouts are considered. In addition, a small change is made in the fading factor calculating equation in order to ensure the tracking performance of STF. Taking advantage of its good robustness against sudden changes, a novel system consisting of two STF-based models is constructed and the bias between their estimated states is treated as a residual. A fault can be alarmed through the Monte Carlo simulation method opted threshold. Meanwhile, it can also be isolated by the idea of residual contributing degree. Some simulation studies are carried out on an Internet-based three-tank system to show the effectiveness of the proposed approach.     

轴承预紧力对滚珠丝杠系统动态特性影响分析

为了解轴承预紧力对滚珠丝杠系统动态特性的影响,以某卧式磨床滚珠丝杠为研究对象,建立了丝杠的三维模型,并以弹性支承约束模拟角接触球轴承对丝杠的支承。在此基础上,利用ANSYS对磨床滚珠丝杠系统进行模态分析。通过修改不同预紧力下轴承的支撑刚度,得到了在不同预紧力下的系统各阶固有频率。分析结果表明,在不同的轴承预紧力下,滚珠丝杠系统的结构刚度会发生变化,使系统的固有频率改变,且随着预紧力增大而增大。磨削状态稳定时,磨削预应力对滚珠丝杠系统的影响较小。     

地埋管地源热泵系统的研究现状

介绍了地埋管地源热泵系统的工作原理,阐述了地埋管地源热泵系统的国内外研究现状。目前地源热泵在我国还处于起步阶段,但随着政府、工程技术人员及社会各界的共同努力,再加上该系统在节能和环保方面的优越性,这项技术将有广阔的发展前景。     

Fault Diagnosis of Time-Varying Parameter Systems With Application in MEMS LCRs

Multiple-model adaptive estimation (MMAE) is a well-known technique used for model matching of deterministic parameter systems. This technique can be used in fault diagnosis by allocating a model to each type of fault. In each contingency, the model that represents the behavior of the actual system can indicate the type of fault occurrence. Kalman filters are generally used in modeling and residual-signal generation of time-invariant systems. Slowly time-varying parameter systems, however, require a system identification unit in addition to the model-matching core. This paper utilizes the least square forgetting-factor technique in parameter identification of slowly time-varying systems and combines it with MMAE for fault-diagnosis applications in microelectromechanical-systems (MEMS) lateral comb resonators (LCRs). Prescheduled faults were designed for simulations and experimentally examined in real-time implementations of estimation-based diagnosis technique for two fabricated MEMS LCRs. It is shown that the application of a system identification unit significantly increases the performance of the fault diagnosis in MEMS devices.     

六阶带通重低音扬声器系统参量设定

随着数字技术的快速发展,多声道放声设备已由专业领域广泛进入寻常百姓家庭。5．1声道环绕声音频系统制式也基本确立（MPEG2 AUDIO;Dolby AC3）,该系统采用一个重低音声道集中重放纯低音的格式,有效地降低了对其它各声道的低音重放要求,从而可明显节省造价,因此,重低音扬声器箱的优化设计显得尤为重要。就目前对该系统参量的设定方法而言,虽已有文献1,2对系统响应函数作了归一化表述;以及频响与系统参量的关系作了定性分析,但工程设计更希望提供定量设定的实用方法,并尝试为CAD建立一个数字模型。该系统的典…     

电参量测试仪的系统设计

介绍了谐波功率测量的数字信号处理算法以及一种基于DSP技术的多功能电参量测量仪的系统设计。采用DSP和MPU及A/D等集成电路构成系统实现了电流和电压的平均值、有功功率及功率因数等电力参数的测量及波形显示。本系统还可以通过通信模块进行远程测量和数据传输。