超厚铜线路板阻焊加工方法

本文阐述了一种超厚铜线路板的阻焊层加工方法,加工方法主要是:在形成外层图形时贴两层厚度为50μm的干膜,阻焊时采用现在比较流行的静电喷涂工艺代替传统的平面阻焊印刷加工工艺,静电喷涂时采用四遍喷涂、两遍预烘-曝光-显影-固化的方式进行加工,前两遍和后两遍静电喷涂之间不预烘-曝光-显影-固化而只采用冷风吹的方式;经过该方法加工出的外层铜箔厚度为12oz,线路拐角油墨厚度为8μm的线路板。利用该工艺加工超厚铜线路板即缩短了生产流程,降低了生产成本,又避免了平面印刷引起的线路间空气排不净而产生的气泡问题,最终固化采用从低温到高温的分段固化方式能够避免因油墨太厚而产生的油墨裂纹问题,提高了线路板的可靠性。     

一种用于生化传感检测的压电式行波微流泵的研究

为了减少生化传感器中样品的消耗,基于行波原理,本文设计了一种新型的压电式微流泵.首先,理论证明了行波的产生机理,并用流体仿真软件Fluent进行了验证;其次,设计并制作了锯齿沟道和直沟道两种结构的微流泵,在压电双晶片阵列的驱动下,测量了这两种微流泵在不同频率和电压下的特性.结果表明锯齿形沟道结构的压电式行波微流泵性能更...     

一种用于有机磷农药检测的微流控传感器

成功制作出一种用于检测有机磷农药的聚二甲基硅氧烷(PDMS)微流控传感器,该传感器集成了光纤和用于固定有机磷水解酶的SU-8圆柱.检测原理基于反应产物对光的吸收,不同浓度有机磷农药的实验结果显示:该传感器的线性相关系数为0.9934.实验结果展示了一种将酶固定在微流沟道的简单方法.简单的制备工艺和便携式的器件为集成化的...     

基于微流控芯片的癌细胞分选仪硬件系统设计

设计了基于微流控芯片的癌细胞分选仪的硬件系统。系统采用光电倍增管(PMT)采集微流控芯片沟道内流动细胞的荧光信号,通过设计的微弱电流信号采集电路进行光电倍增管输出信号的处理,完成对细胞微弱荧光信号的检测。此外,设计了0~1 200 V范围幅值与脉宽可调的高压脉冲源,可产生随机高压脉冲用于癌细胞的分选。整个系统实现了微流控芯片上癌细胞检测、计数以及分选的结合。     

柔性微图形成型技术研究

柔性微图形成型技术是微细加工技术的一个新的方向。介绍了一种新的柔性成型系统——三维定位压控微流系统，并用它制作了柔性微五边形、六边形和微沟道。     

聚二甲基硅氧烷微流控芯片的制备

采用印刷电路板技术加工出芯片模具,以聚二甲基硅氧烷(PDMS)为材料制作出微流控芯片。该芯片由基片和盖片组成,微流控沟道位于基片上,深度和宽度分别为75μm和100μm,由盖片对其进行密封。考察了有绝缘漆模具和无绝缘漆模具制作的芯片的电泳分离情况。在该PDMS微流控芯片上对用异硫氰酸酯荧光素标记的氨基酸进行了电泳分离,当信噪比S/N=3时,最小检测浓度达到0.8×10-11mol/L。     

光纤型微流控电泳芯片的研制

介绍了一种光纤型微流控电泳芯片,该芯片主要由两部分组成:多模光纤,PDMS基片和盖片.利用二次曝光技术制作出芯片的模具;通过浇注的方法制成电泳芯片;实现了在PDMS上制作深度不同的微流控沟道和光纤沟道,使光纤与微流控沟道能够方便地对准;利用异硫氰酸酯荧光素考察了系统的性能,最小检测浓度达到1.3×10-7mol/L,信噪比S/N=5.     

基于石英和载玻片的微电极制备工艺研究

研究以石英片和载玻片为基底的微电极制备工艺,以较常见的叉指型电极为例,基于光刻工艺中各工艺参数要求,重点研究曝光和显影时间对微电极的影响。制得的2种不同基底的电极,采用对比度、精度等关键参数进行分析,最终确定选用载玻片作为芯片基底并获得其最佳工艺参数;制作带电极的PDMS—玻璃微流控芯片,通过实验,成功观察到酵母菌细胞的正、负介电泳现象。     

低成本聚合物微流控芯片加工技术综述

针对传统微流控芯片加工方法成本高昂、耗时长的问题,近年来出现了多种低成本的微流控芯片加工方法,在聚合物、纸等材料上加工、完成了能够满足其应用需求的微流控芯片。对当前各类基于聚合材料的低成本微流控芯片加工技术进行了梳理和总结,并对未来低成本微流控芯片的发展进行了展望。     

采用SU—8胶制作模具的工艺研究

主要描述了SU—8胶制造微流体芯片用模具的工艺研究。讨论了各工艺流程主要包括有前烘、中烘、光刻、显影等因素对模具的影响。提出了一个可供参考的模具制作工艺流程,对抗粘层工艺进行了讨论。另外,在模具制造过程中加入反应离子刻蚀(RIE)来提高SU—8与硅基底的粘附性。最终通过上述的工艺研究,成功制作出了应用于流体的模具,并制造成了微流控芯片。     

A leucocytes count system from blood smear images

Automated blood cell counting instruments are very important tools, daily used by haematologists and medical analysts to perform a complete blood count (CBC). The results of the CBC may be complex to interpret but could lead to important decisions regarding the patient medical treatment. The main focus of this research is oriented to a CBC technique, named white blood cell count (WBCC). Generally, the WBCC is performed by skilled medical operators on peripheral blood smears in order to make a correct count and to obtain useful information such as cell abnormalities or the physical status. The manual WBCC is associated with several challenges, in fact it is a time-consuming, labour intensive and expensive process. This paper introduces a reliable automated WBCC system based on image processing techniques. The main aims are to speed up and to improve the accuracy of the WBCC process. The proposed automated system introduces a new approach to segment white blood cells taking into account the knowledge acquired from a training set formed of the three main classes elements, the white blood cells, the red blood cells and the plasma present in a blood smear image. The segmented regions containing only the white blood cells are subjected to a further step in which the count is performed using the circular Hough transform exploiting the grey-level information. The method has been tested on three different public datasets, in order to highlight the accuracy of the segmentation approach with different colour images and illumination conditions. The experimental results obtained on these datasets demonstrate that the proposed method is very accurate and robust achieving an accuracy of at least 99.2 % in white blood cells counting.     

血压的自适应控制

根据生物体血压控制特点及控制环境，本文提出了一种自适应控制方法，该方法使用最大似然法和递推最小二乘法建立生物体血压的数学模型和估计模型系数，使用控制加权和控制变化率加权，可避免控制过大和控制过快等情况，使用计算机，微流量泵及传感器，构成一血压控制闭环系统。     

基于FPGA的电机动态扭矩测量方法研究

为了提高光电式扭矩测量系统的灵敏度和系统的抗干扰的能力,设计了一种基于现场可编程门阵列(FPGA)和多路状态比较的扭矩测量系统,利用光电式多码道编码盘的旋转角测量功能进行扭矩测量.介绍了多码道码盘输出的多路信号的特征和状态细分的方法,并分析了扭矩测量的原理.硬件上采用FPGA来实现逻辑控制和数据的计数、锁存,简化了系统电路.并且把计数和状态信号传输到上位机进行处理显示,以便实时分析扭矩信号的振动.试验结果验证了该方案可应用于大型机械的动态扭矩测量系统.     

Time assignment speech interpolation system—a microprocessor based design

A normal synchronous time multiplexed system has low capacity utilisation of a trunk channel, owing to the ON-OFF nature of speech in human conversation. A time assignment speech interpolation (TASI) system nearly doubles this efficiency, at relatively small increase in hardware cost. In TASI, during the silent period of speech, the channel is allotted to some other ‘active’ subscriber on a first-come-first-serve basis. A microprocessor based system offers a very cost effective solution from hardware count. Intel 8085 A has been selected for the purpose. The microprocessor functions in a distributed processing mode together with the main CPU controlling the stored program exchange. The system uses digital dynamic speech detectors for detecting transitions in speech over a channel, as they show considerably superior performance over amplitude detectors. An assembly language program for the system has been developed.     

Color fidelity and visibility enhancement of underwater image de-hazing by enhanced fuzzy intensification operator

This paper presents an optimization based algorithm for underwater image de-hazing problem. Underwater image de-hazing is the most prominent area in research. Underwater images are corrupted due to absorption and scattering. With the effect of that, underwater images have the limitation of low visibility, low color and poor natural appearance. To avoid the mentioned problems, Enhanced fuzzy intensification method is proposed. For each color channel, enhanced fuzzy membership function is derived. Second, the correction of fuzzy based pixel intensification is carried out for each channel to remove haze and to enhance visibility and color. The post processing of fuzzy histogram equalization is implemented for red channel alone when the captured image is having highest value of red channel pixel values. The proposed method provides better results in terms maximum entropy and PSNR with minimum MSE with very minimum computational time compared to existing methodologies.     

Epidermal antenna in palmar arch region for anaemia detection to avoid peripheral perfusion artifact in optical sensor during hemoglobin measurement

The anaemia disease diagnosed with various test such as complete blood count (CBC), ferritin measure, reticulocyte count, peripheral smear and blood gas analyser. The ferritin measure the storage and usage of iron in human body, reticulocyte count assess young red blood cell, and Peripheral smear analyse the cell colour, size, and shape of red blood cell through microscopic image. The blood gas analyser measures methemoglobin (MetHb) and carboxyhaemoglobin. Different test measure haemoglobin, since iron level show normal in blood for the patient with low total body iron. The iron deficiency never show symptom or sign in the human body. In this paper, we propose a new non-invasive method for anaemia measure through epidermal antenna over ulnar region of palm and acquire radiating signal from Haemoglobin protein. The acquired signal from epidermal antenna analysed with Transverse Dyadic Wavelet Transform for haemoglobin protein level in red blood cell. The epidermal antenna signal from ulnar region haemoglobin measurement avoids the peripheral perfusion artifact of optical or image sensor which arise during measurement. The experimental analysis show signal of epidermal antenna measure the haemoglobin more accurately, through regression modelling than existing optical and image based point of care device. Experimental result of haemoglobin measurement from ulnar region has validated with blood gas analyser.

     

Microfluidic device for continuous magnetophoretic separation of white blood cells

This paper presents a microfluidic device for magnetophoretic separation of red blood cells from blood under continuous flow. The separation method consists of continuous flow of a blood sample (diluted in PBS) through a microfluidic channel which presents on the bottom “dots” of ferromagnetic layer. By applying a magnetic field perpendicular on the flowing direction, the ferromagnetic “dots” generate a gradient of magnetic field which amplifies the magnetic force. As a result, the red blood cells are captured on the bottom of the microfluidic channel while the rest of the blood is collected at the outlet. Experimental results show that an average of 95% of red blood cells is trapped in the device.     

Effect of Count Estimation in Finding Frequent Itemsets over Online Transactional Data Streams

A data stream is a massive unbounded sequence of data elements continuously generated at a rapid rate. Due to this reason, most algorithms for data streams sacrifice the correctness of their results for fast processing time. The processing time is greatly influenced by the amount of information that should be maintained. This issue becomes more serious in finding frequent itemsets or frequency counting over an online transactional data stream since there can be a large number of itemsets to be monitored. We have proposed a method called the estDec method for finding frequent itemsets over an online data stream. In order to reduce the number of monitored itemsets in this method, monitoring the count of an itemset is delayed until its support is large enough to become a frequent itemset in the near future. For this purpose, the count of an itemset should be estimated. Consequently, how to estimate the count of an itemset is a critical issue in minimizing memory usage as well as processing time. In this paper, the effects of various count estimation methods for finding frequent itemsets are analyzed in terms of mining accuracy, memory usage and processing time.     

采用双尺度图像分解的水下彩色图像增强

目的 为解决水下图像的色偏和低对比度等问题,提出一种基于双尺度图像分解的水下彩色图像增强算法。方法 通过基于均值和方差的对比度拉伸方法改善图像的色偏问题,并利用中值滤波降低红通道对比度拉伸后引入的噪声;采用双尺度图像分解绿通道图像补偿红通道图像细节;在处理后的红通道图像中引入原始图像红通道的真实细节与颜色。结果 选取不同水下图像作为实验数据集,将本文方法与暗通道先验的方法、基于融合的方法、自动红通道恢复方法以及一种基于卷积神经网络深度学习的方法相比较,首先从主观视觉效果进行定性分析,然后通过不同评测指标进行定量分析。主观定性分析结果表明,提出的方法相比较其他方法能够更好地解决图像色偏和红色阴影问题;定量分析中,自然图像质量评价（natural image quality evaluation,NIQE）指标和信息熵（information entropy,IE）值较基于融合的方法和深度学习的方法分别提高了1.8%和13.6%,且水下图像质量评价指标（underwater image quality measurement method,UIQM）较其他方法更优。结论 提出的双尺度图像分解方法利用水下图像成像特点解决图像色偏以及低对比度问题,具有良好的适应能力,同时算法复杂度低且鲁棒性较高,普遍适用于复杂的水下彩色图像增强。     

基于双DSP的高速数据采集控制器的设计

提出了一种由基于McBSP接口的双DSP并行处理系统，采用双处理器流水线体系结构，一个DSP负责进行各回路电压电流的采集、滤波、迭代计算，另一个DSP负责人机交互、远程通信与实时控制，二者并行工作可显著提高系统的处理能力，以此并行计算机结构为核心设计实现了高压电力无功补偿(SVC)信号处理系统。