精密空气静压导轨组件的设计与分析

运用气体润滑技术设计出了一套空气静压导轨组件。该组件可以立、卧式放置,具有多种机械安装接口,能在各种不同结构和要求的加工及测量设备中安装使用。对该组件的整体结构进行了设计和论证,经试验调试该设计的组件总体性能优良,完全能够达到预期的设计目的。     

竹原纤维酶处理的纤细化效果

为了探讨竹原纤维酶处理纤细化的有效方法,应用漆酶、精练酶及精练酶+漆酶二步法经正交设计对已制得的竹原纤维进行纤细化处理试验,测定酶处理后竹原纤维的细度变化率、木质素含量及强度。结果表明:精练酶去除木质素的效果比漆酶好,而精练酶+漆酶二步法处理的效果均较精练酶或漆酶单独处理为好,二步法处理后竹原纤维的细度变化率为51.33%,木质素含量从原来的18.98%降为5.49%。     

五轴激光内雕控制系统的设计

针对频繁起停,要求快速准确定位的激光内雕机,自主设计了一种能高速运行的数控装置。其核心是以PC机和DSP组成控制系统,将振镜电机和步进电机有效组合,组成五轴伺服传动,满足运动轴高速高精的控制要求。文章详述了激光内雕系统的构成,工作原理和各部分接口的实现。     

用派克方程分析开关磁阻电动机

根据开关磁阻电动机气隙磁导的变化情况，把ＳＲＭ的一相绕组通电后的电磁关系，等效成一台假想的极对数Ｚ２／２，但运行于某种不对称的工作条件的三相凸极同步电动机的电磁关系，建立了与ＳＲＭ相等效的同步电动机模型，使用派克方程来分析ＳＲＭ的工作机理成为可能，并用坐标变换、Ｚ变换和拉氏变换法来求取ＳＲＭ的定子相绕组电流及电磁转矩。，     

预氧化与催化臭氧化深度处理工艺的生产运行效果

通过生产运行分析了生物预氧化、梯级催化臭氧化-生物活性炭滤池深度处理组合工艺在生产应用中的综合净化效果,分别评价了各处理单元的净化效能。生产运行结果表明,生物预氧化对氨氮的平均去除率为62％,但处理效果受温度变化的影响;生物预氧化对CODMn的去除作用有限,对锰的平均去除率为58％;高密度沉淀池对浊度、色度、铁、锰具有良好的去除作用,对CODMn的去除率为28％;臭氧总投量相同时,与催化臭氧化一次性投加相比,预氧化与催化臭氧化分别投加更有利于减少溴酸盐的生成;半挥发性微量有机污染物主要在催化臭氧化阶段去除,去除率为44％。     

Evaluation of moving‐line contrast degradation without motion

Abstract— A method for evaluation of the contrast of moving step‐grating patterns under smooth‐pursuit eye‐tracking conditions without imaging data acquisition and image analysis is introduced. Periodic optical responses of the display to a set of simple driving signals have been recorded at a fixed location, and the luminance vs. time data has been evaluated to obtain two types of contrast for characterization of the dynamical performance of the display under test: the frame‐convoluted contrast and the frame‐integrated contrast. The relation of this characterization with respect to modulation transfer functions from impulse responses and to the dynamic modulation transfer function from sine‐gratings is explained and discussed. The approach described here provides a detailed and comprehensive characterization of the dynamical properties of electronic displays including both extreme cases of step‐response and impulse‐response with quantities that are related to visual perception. With this type of evaluation, the visual resolution of displays can be described by the same characteristics in the static and the dynamic case. The method is attractive due to limited instrumental efforts and the transparent method of evaluation.     

大流量电液比例插装阀液压测试试验台的设计

电液比例插装阀可以实现对高压大流量液流的比例控制,广泛应用于锻压机、注塑机等重型机械液压系统的调速回路,其性能直接影响到系统的响应速度和控制精度,电液比例插装阀的测试和调节是确保压机安全可靠运行的必要手段。本文根据压机应用工艺对电液比例插装阀的性能要求,设计了液压测试试验台,对其压力—流量特性和阶跃响应特性进行测试,能够准确的测试该阀的主要性能。     

Failure load prediction and optimisation for adhesively bonded joints enabled by deep learning and fruit fly optimisation

Adhesively bonded joints have been extensively employed in the aeronautical and automotive industries to join thin-layer materials for developing lightweight components. To strengthen the structural integrity of joints, it is critical to estimate and improve joint failure loads effectually. To accomplish the aforementioned purpose, this paper presents a novel deep neural network (DNN) model-enabled approach, and a single lap joint (SLJ) design is used to support research development and validation. The approach is innovative in the following aspects: (i) the DNN model is reinforced with a transfer learning (TL) mechanism to realise an adaptive prediction on a new SLJ design, and the requirement to re-create new training samples and re-train the DNN model from scratch for the design can be alleviated; (ii) a fruit fly optimisation (FFO) algorithm featured with the parallel computing capability is incorporated into the approach to efficiently optimise joint parameters based on joint failure load predictions. Case studies were developed to validate the effectiveness of the approach. Experimental results demonstrate that, with this approach, the number of datasets and the computational time required to re-train the DNN model for a new SLJ design were significantly reduced by 92.00% and 99.57% respectively, and the joint failure load was substantially increased by 9.96%.     

应用于光储系统中的改进型扰动观察MPPT算法

本文提出了一种改进的步长可变、稳态时无振荡的扰动观察MPPT算法,该改进算法在保持基本的扰动观察法简单以及便于实现特点的同时,还能停止稳态振荡并具备良好的追踪速度.该算法首先通过变步长实现快速跟踪最大功率点,当确定到达稳态之后,停止人工扰动,实现无振荡稳定输出功率,从而减少因振荡造成的功率损耗,提高了整个系统的效率.当...     

Modified La0.6Sr0.4Co0.2Fe0.8O3-δ cathodes with the infiltration of Er0.4Bi1.6O3 for intermediate-temperature solid oxide fuel cells

Aiming to lower the activation energy and expedite the oxygen reduction reaction (ORR) process of La_0.6Sr_0.4Co_0.2Fe_0.8O_3-δ (LSCF) cathodes for application in intermediate-temperature solid oxide fuel cells (IT-SOFCs), Er_0.4Bi_1.6O₃ (ESB) modified LSCF was prepared by infiltrating using organic solvents. The infiltration of ESB dramatically reduces the polarization resistances of LSCF cathodes (from 0.27 to 0.11 Ω cm² at 700 °C, from 0.58 to 0.25 Ω cm² at 650 °C), and lowers their activation energy (from 100.28 to 97.15 kJ mol^?1). Also, ESB makes the rate-limiting step of LSCF cathodes at high frequency change from the charge transfer process on the cathode to the adsorption and diffusion of oxygen on cathode surface. The single cell with ESB infiltrated LSCF cathodes shows a peak power density of 469 mW cm^?2 at 700 °C using humid hydrogen and air as fuels and oxidants, respectively, as well as a good short-term stability for 50 h.