光配向制程参数对预倾角及其光电性能的影响

为了满足市场对LCD面板高对比度、高画质的需求,光配向作为一种非接触式的新型配向方法正被广泛研究。本文采用光裂解型聚酰亚胺取向材料制备得到IPS型测试液晶盒,并针对光配向成膜条件与其所形成的光电效应进行研究。通过FT-IR、AFM、偏光板角度测试机等仪器对不同pre-bake和post-bake温度和时间下的测试盒的预倾角及光电特性进行了表征。结果显示,pre-bake、post-bake的温度和时间与预倾角、穿透率、对比度和电压保持率均存在一定的相关性。本文的研究可以为后人对光配向制程相关参数的优化提供借鉴。

印制电路板镀通孔制程可靠性问题与研究技术途径

影响镀通孔制程可靠性因素众多,关系复杂,需要一个有效的技术途径来研究该问题。文中总结了印制电路板镀通孔制程的各个加工步骤和工序的目的,以及制造过程中影响这些目的达成效果的影响因素。分析汇总了印制电路板镀通孔的各种失效模式和机理,及其对应的失效发生的部位和影响因素。在此基础上,明确了进行印制电路板镀通孔制程可靠性研究的技术途径,同时给出了实施这项研究的技术细节。

激光技术制备微流道的研究

采用YAG雷射制程技术制备微流道,不但处理速度快、低污染、低耗费,硅芯片经YAG雷射表面处理后呈现微流道,实验得出雷射光斑直径受频率及电流强度所控制,随着频率减少及电流强度增加而变大,微流道宽度随着频率减少及电流强度增加而变宽,扫描速度对微流道宽度无明显影响。微流道深度随着频率及电流强度增加而变深,随着扫描速度增加而变浅。微流道热影响区在各制程参数下,其影响的变化差异并不明显,微流道表面粗糙度随着频率及电流强度的增加而变大,随着扫描速度的增加而降低,最佳制程参数为扫描速度10mm/s、电流10A及频率1KHz,其微流道表面及轨迹最为平整,且几何形狀最佳。

YAG雷射技术制备微流道的研究

采用YAG雷射制程技术制备微流道,不但处理速度快、低污染、低耗费,硅芯片经YAG雷射表面处理后所呈现微流道,实验得出雷射光斑直径受频率及电流强度所控制,随着频率减少及电流强度增加而变大,微流道宽度随着频率减少及电流强度增加而变宽,扫描速度对微流道宽度无明显影响。微流道深度随着频率及电流强度增加而变深,随着扫描速度增加而变浅。微流道热影响区在各制程参数下,其影响的变化差异并不明显,微流道表面粗糙度随着频率及电流强度的增加而变大,随着扫描速度的增加而降低,最佳制程参数为扫描速度10mm/s、电流10A及频率1KHz,其微流道表面及轨迹最为平整,且几何形状最佳。

YAG雷射技术制备微流道的研究

用YAG雷射表面处理技术在硅芯片上制备微流道,并分析频率、电流强度及扫描速度对于微流道宽度、深度、热影响区及表面粗糙度之影响。实验结果显示：光斑大小随着频率的增加而减少,但却随着电流强度的增加而增加;微流道宽度则直接决定于光斑之大小;微流道深度及表面粗糙度皆受到频率、电流强度及扫描速度三种制程参数影响;而微流道热影响区在各制程参数下,其影响的变化差异并不明显。研究中当扫描速度10mm/s、电度10A及频率1KHz为最佳制程参数。

基于大数据分析的产品质量异常侦测研究

众所周知,常规产品不良分析方法通过经验分析不良成因及发生位置,并根据少量数据推断存在问题的设备。这种分析方法费时费力,验证周期长,准确度低;为改善这一状况,本文基于FDC(Fault Detection and Classification)系统,利用JMP、Minitab等品质分析工具,通过大量收集不良发生前、发生时、发生后的数据,得到FDC大数据分析五步法,使得验证周期减少70%以上,准确率达85%以上,极大地提高了产品不良改善效率。

低成本中Tg板材精益加工的研究

中您板材在16L／板厚2．5mm、20L／板厚3．0mmPCB应用上开始逐渐替代高您FR-4板材。选择价格更加低廉的中您板材是PCB厂家成本节省的重要途径，同时对中Tg板材进行精益加工是PCB厂大幅降低加工成本且保证品质行之有效的另一途径。文章围绕某低成本中Tg板材——R板材开展精益加工的研究。从层压、钻孔参数、钻孔后烘板以及去钻污等关键制程着手，深入研究各关键制程、不同叠层设计对PCB孔壁质量及可靠性的影响。在保证PCB可靠性、CAF特性良好的前提下，确定该R板材最优化的加工参数，实现低成本中Tg板材的精益加工。

Design and Performance Analysis of Micro Proton Exchange Membrane Fuel Cells

This study describes a novel micro proton exchange membrane fuel cell(PEMFC)(active area,2.5 cm2).The flow field plate is manufactured by applying micro-electromechanical systems(MEMS) technology to silicon substrates to etch flow channels without a gold-coating.Therefore,this investigation used MEMS technology for fabrication of a flow field plate and presents a novel fabrication procedure.Various operating parameters,such as fuel temperature and fuel stoichiometric flow rate,are tested to optimize micro PEMFC performance.A single micro PEMFC using MEMS technology reveals the ideal performance of the proposed fuel cell.The optimal power density approaches 232.75 mW·cm-1 when the fuel cell is operated at ambient condition with humidified,heated fuel.

IMC based robust PID controller tuning for disturbance rejection

It is well-known that the IMC-PID controller tuning gives fast and improved set point response but slow disturbance rejection. A modification has been proposed in IMC-PID tuning rule for the improved disturbance rejection. For the modified IMC-PID tuning rule, a method has been developed to obtain the IMC-PID setting in closed-loop mode without acquiring detailed information of the process. The proposed method is based on the closed-loop step set point experiment using a proportional only controller with gain K_(c0). It is the direct approach to find the PID controller setting similar to classical Ziegler-Nichols closed-loop method. Based on simulations of a wide range of first-order with delay processes, a simple correlation has been derived to obtain the modified IMC-PID controller settings from closed-loop experiment. In this method, controller gain is a function of the overshoot obtained in the closed loop set point experiment. The integral and derivative time is mainly a function of the time to reach the first peak(overshoot). Simulation has been conducted for the broad class of processes and the controllers were tuned to have the same degree of robustness by measuring the maximum sensitivity, Ms, in order to obtain a reasonable comparison. The PID controller settings obtained in the proposed tuning method show better performance and robustness with other two-step tuning methods for the broad class of processes. It has also been applied to temperature control loop in distillation column model. The result has been compared to the open loop tuning method where it gives robust and fast response.

Research on PCC Control Method for Ribbon-free Random Winding

Based on analyzing the overlap appearance of random winding, basic principles of ribbon-free random winding and parametric selections for anti-overlap are discussed. The ribbon-free random winding control system and its related hardware construction as well as its software design are introduced by applying PCC technology to high speed spinning machine of synthetic filament.

On Stabilizing Sets of PI Controllers for Multiple Time Delayed Process

This paper considers the problem of stabilizing multiple time delayed processes using proportional integral(PI) controller.The presented approach is based on finding all possible values of control parameters which will result in pure imaginary roots of closed loop characteristic equation under all process parameters fixed.The ergodic search of three PI control parameters are converted from the range of infinity to finite range by introducing trigonometric tangent function.After all possible stability boundaries are obtained,the Nyquist stability method is used to determine the actual stability region of the controller parameters.This method also permits design for simultaneous minimum gain and phase margin requirement.An illustrative example case is also presented.

Investigation into co-pyrolysis characteristics of oil shale and coal

Samples of five types of coal and oil shale from the Daqing region have been subjected to co-pyrolysis in different blending ratios with thermo-gravimetry （TG）, given a heating rate of 30 ℃/min to a final tem- perature of 900 ℃. Investigations on pyrolysis of mixing coal and oil shale in different proportions were carried out, indicating that the main scope of weight loss corresponding to hydrocarbon oil and gas release was between 350 and 550 ℃. At higher temperatures, significant weight loss was attributed to coke decomposition. Characteristic pyrolysis parameters of blends from oil shale and the high ranked XZ coal varied with the blending ratio, but oil shale dominated the process. At the same blending propor- tions, highly volatile medium and low ranked coal of low moisture and ash content reacted well during pyrolysis and could easily create synergies with oil shale. Medium and high ranked coal with high mois- ture content played a negative role in co-pyrolysis.

Control for Modified University of Cape Town Process Using Oxidation-Reduction Potential in the Second Anoxic Zone

The aim of this work is to evaluate the feasibility of applying the technology of oxidation-reduction potential （ORP） control on the municipal wastewater treatment system for nitrogen and phosphorus removal. Meanwhile the relation between the optimal ORP （ ORPopt ） and influent C/N ratio was evaluated, in which the influent chemical oxygen demand （ COD ） concentration was stabilized at （290 ± 10 ） mg/L, the influent total phosphorus （TP） concentration was stabilized at （7.0 ± 0.5 ） mg/L. The results indicated that： （1） the ORP in the second anoxic zone had effect on nitrogen and phosphorus removal capability, and the average percentages of phosphorus uptake in ANO2 zone （ ηa ） increased with increasing ORP, i. e. , increasing from 12. 0% at - 143 mV to 22.0%,30.0%,37.0%, and45.0% at -123, -111, -105 and -95 mV, respectively; （2） the ORPopt as function of influent C/N ratio could be calculated by the equation： y ffi 252. 73e〈 -x/3.39） _ 131.01 ; the maximum percentage of phosphorus uptake in ANO2 as function of the ORPopt could be calculated by the equation： y ffi -0.49e（x/15.58） ＋ 1. 51. The ORPopt was the important process control parameter that must be optimized for operation of enhanced biological phosphorus removal （ EBPR ） system. Moreover, ORP sensor is very simple, and the industrial applications of this strategy is practical.

Adaptive SPC monitoring scheme for DOE-based APC

Automatic process control (APC) based on design of experiment (DOE) is a cost-efficient approach for variation reduction. The process changes both in mean and variance owing to online parameter adjustment make it hard to apply traditional SPC charts in such DOE-based APC applied process. An adaptive SPC scheme is developed, which can better track the process transitions and achieve the possible SPC run cost reduction when the process is stable. The control law of SPC parameters is designed by fully utilizing the estimation properties of the process model instead of traditionally using the data collected from the production line. An example is provided to illustrate the proposed adaptive SPC design approach.

Technological Parameters for Preparation and Granulation of Ammonium Ion-Exchange Material

As a raw material,kaolin was modified to prepare a high-performance ammonium ion-exchange material.According to cation-exchange capacity (CEC) measurement,the prepared ammonium ion-exchange material has an ammonium ion-exchange capacity greater than 75mg/g and can be used to remove ammonia nitrogen in water treatment.A pharmaceutical extruder-rounder was used to study the effects of granulation process.Polyethylene glycol6000 (PEG-6000) was used as the pore-forming agent and calcining temperature of 650℃ was used as the optimal condition.NMR data indicate that 27 Al is mainly converted from hexa-coordinated Al to tetra-coordinated Al during the modification.Compared with 29 Si in the original kaolin,29 Si in the modified kaolin does not have an obvious change.A comparison of the data with Langmuir and Freundlich isotherm models shows a good correlation.The Freundlich model describes the process more accurately,and the adsorption process of ammonia nitrogen in water with the ammonium ion-exchange material closely matches the pseudo-second-order reaction.

Modeling of Welding Process by Robotic Vision

Modeling of welding process by robotic vision is basically a theoretical problem, means mainly on physical problem, and also technological problem. To obtain a good model of welding process by robotic vision, theoretical researches are required but also constant experimental researches of several welding processes. Until today researches of welding processes has been based on empirical and detailed experimentation. This paper presents welding process by robotic and automation points of view with application of new technologies. Welding robotic system has been designed with possibility to control and inspect this process. Parameters that should be controlled during the process have been identified to reach desired quality. Figure of control system of welding process by robotic vision is given in this paper.

Harmony search algorithm with differential evolution based control parameter co-evolution and its application in chemical process dynamic optimization

A modified harmony search algorithm with co-evolutional control parameters(DEHS), applied through differential evolution optimization, is proposed. In DEHS, two control parameters, i.e., harmony memory considering rate and pitch adjusting rate, are encoded as a symbiotic individual of an original individual(i.e., harmony vector). Harmony search operators are applied to evolving the original population. DE is applied to co-evolving the symbiotic population based on feedback information from the original population. Thus, with the evolution of the original population in DEHS, the symbiotic population is dynamically and self-adaptively adjusted, and real-time optimum control parameters are obtained. The proposed DEHS algorithm has been applied to various benchmark functions and two typical dynamic optimization problems. The experimental results show that the performance of the proposed algorithm is better than that of other HS variants. Satisfactory results are obtained in the application.

Programming a Parametric Design Algorithm to Improve Manufacturing Processes＇ Efficiency： The Case Study of Glued-Laminated Timber

In the last decade, parametric and generative design techniques become quite popular for form-finding strategies or for pushing automation in design processes. Nevertheless, these techniques could be applied in engineering processes as well in order to improve the effectiveness and the efficiency of manufacturing processes in BI （building industry）. Focusing on the case study of GLT （glued-laminated timber）, this paper shows the procedure of programming a parametric algorithm adopted by authors that pursues two specific design intents： reducing the usage of unneeded high-quality raw material and improving the efficiency of production processes by producing DF （digital fabrication） contents for standard production systems of GLT. According to different European and international standards, thanks to FEM （finite element model） simulations and curvature analysis, the algorithm allows saving at least 33% of high-quality raw material and, according to early first surveys on a standard production system, 30% of operation time among product engineering-processes.

Direct spray pyrolysis of aluminum chloride solution for alumina preparation

The effects of pyrolysis mode and pyrolysis parameters on Cl content in alumina were investigated, and the alumina products were characterized by XRD, SEM and ASAP. The experimental results indicate that the spray pyrolysis efficiency is higher than that of static pyrolysis process, and the reaction and evaporation process lead to a multi-plot state of the alumina products by spray pyrolysis. Aluminum phase starts to transform into γ-Al2O3 at spray pyrolysis temperature of 600 °C, which is about 200 °C lower than that of static pyrolysis process. The primary particle size of γ-Al2O3 product is 27.62 nm, and Cl content in alumina products is 0.38% at 800 °C for 20 min.

YAG雷射技术制备微流道的研究

用YAG雷射表面处理技术在硅芯片上制备微流道,并分析频率、电流强度及扫描速度对于微流道宽度、深度、热影响区及表面粗糙度之影响。实验结果显示:光斑大小随着频率的增加而减少,但却随着电流强度的增加而增加;微流道宽度则直接决定于光斑之大小;微流道深度及表面粗糙度皆受到频率、电流强度及扫描速度三种制程参数影响;而微流道热影响区在各制程参数下,其影响的变化差异并不明显。研究中当扫描速度10mm/s、电流10A及频率1KHz为最佳制程参数。