Ab initio calculation of adhesion and potential corrugation of diamond (001) interfaces

The system consisting of two diamond (001) surfaces in contact was studied by means of plane-wave/pseudopotential density functional calculations. Different hydrogen coverages, ranging from fully hydrogenation to bare surfaces, were considered. The adhesion energy was calculated as a function of both the separation and the lateral displacement of the two surfaces. The effects of dangling carbon bonds on the adhesion and potential corrugation are quantitatively discussed.     

Dynamic response of diamond sensors to ionizing radiation beams

Prototypes of radiation detectors for clinical dosimetry were constructed using commercially available synthetic diamond. Polished diamond plates of detector grade and standard quality were used. The metallization scheme was a typical Ag–Ag contact for the detector grade diamond and a new metallization technique for the standard quality diamond. This was for determining which detector is more appropriate for radiotherapy dosimetry needs. The detector signal was analyzed as a function of bias voltage in the 0–500 V range both in absence of radiation and in a Co-60 gamma-ray beam. The response linearity was assessed in Co-60 gamma-ray beam for dose-rates in the range from 0.2 to 1.2 Gy min⁻¹. Pre-irradiation effects were also investigated. Signal rise time, signal stability and reproducibility are reported and discussed.     

串口通信在CVD金刚石膜生长系统中的应用

本文主要介绍在CVD金刚石膜生长系统中如何利用MSComm控件实现串口通信，并给出了以Delphi开发的实例程序。此外阐述了以分时循环方式实现单通道多信号采集的原理和实现方案。     

Mechanisms of interaction in acoustic plate mode immunosensors

Acoustic plate mode (APM) sensors have been used to detect immunochemical reactions in on-line measurements. In order to determine the exact mechanisms of interaction involved and to enhance reproducibility, both metallized and non-metallized devices have been investigated. The metallization is found to reduce total frequency shifts by 40–50%, an effect which must be attributed to either acoustoelectric interaction with the protein layer or different mass sensitivities for the different surface boundary conditions. In spite of the lower frequency shifts, metallized sensors may be advantageous for detecting biochemical reactions in ionic solutions because spurious signals are found to be effectively eliminated.     

Effects of diamond and AlN layers inserted beneath the phosphor layer on the discharge characteristics of PDPs

Abstract— In this study, the effects of diamond and AlN layers inserted beneath the phosphor layer of the rear plate of a PDP were investigated. The layers were formed via an osmotic‐pressure coating process. Macrocells and test panels were prepared to examine their effects on luminance and luminous efficacy. The results indicate that the layers primarily affect the glow‐discharge behavior and eventually enhance the luminous efficacy of the PDP, suggesting the possibile improvement in the performance of PDPs.     

基于W77E58的金刚石压机测控系统设计

本文研究了金刚石压机测控系统的主要结构,讨论了温度、压力的检测和控制方法,进行了系统的软硬件设计。     

一种新的陀螺振子及工作方式的研究

本文提出了一种新形式的陀螺振子结构,介绍了其工作原理。当陀螺振子在驱动模态谐振时,检测与驱动正交振动位置的振动情况,推导出了两模态振动公式。利用有限元软件建模,对新振子能否满足驱动与检测模态频率相等的灵敏度要求进行仿真验证。     

半胱氨酸修饰的掺硼金刚石电极用于尿酸的测定

在掺硼金刚石电极表面修饰聚半胱氨酸的电极测定尿酸时抗坏血酸和多巴胺的干扰较低。在方波伏安信号中抗坏血酸或多巴胺与尿酸共存检测时尿酸的特征峰电位变化较小(不超过15mV),峰电流变化只有几微安培。利用循环伏安法、方波伏安法对比了修饰电极与没有经过修饰的电极对尿酸的响应,试验了扫描速度、方波振幅、pH值等对修饰电极性能的影响。在最优条件下,得到测定尿酸的线性范围为1.45×10-9～1.16×10-6mol/L。在上述定性定量分析的基础上对未经预处理的儿童肾病病人尿样进行了检测,得到了令人满意的结果。     

聚晶金刚石复合片崩角缺陷视觉检测技术研究

针对目前国内生产聚晶金刚石复合片(PDC)的企业大多数在表面缺陷检测环节严重依赖于人工检测,存在检测效率低、主观性强等问题,提出了一种基于机器视觉的检测方法替代人工检测.将倒角边缘的崩角缺陷作为检测目标,研究崩角图像的表面特征后,提出了在硬件上使用零角度环形光源突出崩角特征,在检测方式上通过阈值分割、中值滤波进行预处理,然后利用最小二乘法拟合获取倒角圆环的圆心位置和小圆半径并建立掩码,最后通过与(AND)运算提取出崩角信息,进行识别和标记.结果显示:实现对图像中的崩角缺陷自动检测和定位,并且判断标准统一.     

Self-adaptation of learning rate in XCS working in noisy and dynamic environments

An extended classifier system (XCS) is an adaptive rule-based technique that uses evolutionary search and reinforcement learning to evolve complete, accurate, and maximally general payoff map of an environment. The payoff map is represented by a set of condition-action rules called classifiers. Despite this insight, till now parameter-setting problem associated with LCS/XCS has important drawbacks. Moreover, the optimal values of some parameters are strongly influenced by properties of the environment like its complexity, changeability, and the level of noise. The aim of this paper is to overcome some of these difficulties by a self-adaptation of a learning rate parameter, which plays a key role in reinforcement learning, since it is used for updates of classifier parameters: prediction, prediction error, fitness, and action set estimation. Self-adaptive control of prediction learning rate is investigated in the XCS, whereas the fitness and error learning rates remain fixed. Simultaneous self-adaptation of prediction learning rate and mutation rate also undergo experiments. Self-adaptive XCS solves one-step problems in noisy and dynamic environments.     

以双模式工作的远程视频监控系统研究

对基于802.11g ADSL 网络视频会议系统模式和CDMA1X ADSL的双模式工作的远程视频监控系统进行了研究,并进行了部分实际性能的测试,还对系统在实际应用情况下的一些特点进行了研究分析.在以上测试和研究的基础上探讨了无线网络与有线网络的配合覆盖灵活组建实用视频监控系统的问题和规律.     

Direct electrochemical detection of sodium azide in physiological saline buffers using highly boron-doped diamond electrodes

Direct detection of sodium azide was examined by using highly boron-doped diamond (BDD) electrodes in some physiological saline buffer solutions. Three important saline buffers, ADA buffer (N-(2-acetamido) iminodiacetic acid), sodium EDTA and imidazole, were investigated. Hydrogen-terminated BDD was fixed for the investigation since it showed much better sensitivity for azide oxidation in comparison with the oxygen-terminated one. Wide range of buffer concentration was examined. A well-separated peak of sodium azide was observed in its mixture with the buffers, resulting in selective sodium azide detection. The current responses were exactly total addition of sodium azide and buffer current responses. The present method was evidenced to be available for direct detection of sodium azide in two samples of commercial diluents for cell counting. A standard addition method was applied. Sodium azide concentrations of 502 and 1355 μg mL⁻¹ were detected in both samples with the R.S.D.s of 0.07 and 2.37%, respectively. Validation was achieved by the comparison with the sample concentrations given by the manufacturer. Simple, selective, good sensitivity and excellent reproducible detection make the diamond electrodes very attractive for numerous electroanalytical applications.     

Three dimensional thermal finite element simulation of electro-discharge diamond surface grinding

The key to achieve good surface integrity in the workpiece due to Electro-Discharge Diamond Grinding (EDDG) process, which is hybrid of grinding and EDM, is by preventing the excessive temperature and thermal stress generated during the process. EDDG in surface grinding mode called Electro-Discharge Diamond Surface Grinding (EDDSG), used for finishing operation, is a complex machining process where several disciplines of science and engineering are involved in its theory. The complexity of the process includes the random occurrence of spark during EDM process and nonlinear behavior of workpiece material includes temperature dependent thermal properties. The present work involves the development of a simulation model to simulate the complex EDDSG process which consists of simulation of each constituent process namely EDM and surface grinding for temperature and thermal stress distribution. In order to simulate the realistic complex conditions, the three dimensional FEM is used in the process of development of the model accounting the random occurrence of the spark during EDM. The effect of different dielectric fluid, duty factor and energy partition during EDM on the temperature distribution and MRR study related to EDM contribution are reported. It is observed that the spark contributes primarily to the temperature. The predicted results can be used to determine the surface integrity of the machined surface.     

引压方式动态压力传感器研制

介绍了一种通过引压方式探测动态压力信号的传感器。由于受到被测介质温度高和被测环境空间尺寸小限制,传感器需要通过引压管传递动态工作压力。为了保证引压管在传递动态压力过程中不影响传感器的频响特性,设计了一种阻抗匹配结构,减小了引压结构对传感器动态响应特性的影响,保证了动压传感器的频响特性,该传感器的检测单元包括一个引压管、一个敏感元件、一个电路组件、一个阻抗匹配管。测试结果表明：动压传感器具有（31.5～8000 Hz）频响范围。     

Prediction ability of a lumped-element equivalent-circuit model for thickness-shear mode resonators in liquids

The viscosity-density prediction ability of a lumped-element equivalent-circuit model for a thickness-shear mode resonator operating in Newtonian liquids is examined. The model is a Butterworth-Van Dyke equivalent-circuit modification that describes the near-resonance electrical characteristics of a liquid-loaded resonator. By comparing the relative significance of different load contributions, a simplified liquid-phase lumped-element model is introduced. This model is calibrated with an admittance measurement on a resonator in contact with water. With the calibrated model, the liquid viscosity-density product is predicted from measurements made in aqueous glycerol solutions. These predictions are found to be accurate compared to the literature values. In addition, the predicted value for the average surface roughness of the resonator is consistent with the presented SEM micrographs.     

A quick identification model for assessing human anxiety and thermal comfort based on physiological signals in a hot and humid working environment

We propose a simple and quick method for quantifying workers' anxiety and thermal comfort levels using physiological signals. Nine subjects enrolled in a series of controlled laboratory experiments involving varying temperature, relative humidity, and labor intensities. A total of 40 experiments were conducted, and 1592 groups of anxiety data and 1624 groups of thermal comfort data were obtained, respectively. During 2-h-working trials, Electroencephalogram (EEG), photoplethysmography (PPG), and pupil diameter of each subject were collected synchronously, and the State-Trait Anxiety Inventory (STAI) and thermal comfort vote (TCV) were completed in stages. Random Forest was adopted to screen out the appropriate sensitivity feature indicators of anxiety levels and thermal comfort levels from the 70 features of the 10 EEG channels. Finally, Random Forest, Gradient Boosting Decision Tree, K-nearest Neighbor Algorithm, and Support Vector Machine were used to determine relevant physiological data combinations and modeling algorithms. The Precision of the anxiety level and thermal comfort level quick identification model based on Random Forest Algorithm can reach 81.04% and 84.79%, respectively. This suggests that the proposed quick identification method for assessing workers' anxiety and thermal comfort levels holds promise. Physiological data need to be obtained by monitoring only PPG, pupil diameter, and 5 EEG channels. By processing these data, the workers' anxiety and thermal comfort level could be judged realistically to ensure their safety. It is suggested that PPG, pupil diameter, and EEG should be considered all together in the future study of anxiety and thermal comfort.     

电梯上高峰动态规划分区控制方法的研究

研究电梯在上高峰模式下,采用动态规划方法进行动态分区的电梯群控方法.将乘客的乘梯时间和候梯时间作为目标函数,在上高峰模式下对电梯群控的各部电梯进行最优分配,达到节能、快速和提高电梯利用率的目的.通过几种群控算法的仿真比较,验证了基于动态规划方法进行动态分区电梯群控方法的良好效果.     

峰值电流模升压转换器的动态斜坡补偿电路设计

基于HHNEC 0.35 μm BCD工艺设计了一种应用于峰值电流模升压转换器的动态斜坡补偿电路.该电路能够跟随输入输出信号变化,相应给出适当的补偿量,从而避免了常规斜坡补偿所带来的系统带载能力低及瞬态响应慢等问题.经Cadence Spectre验证,该电路能够达到设计要求.     

基于动态学习机制的MAS信任评价方法

为准确评价协作目标,在agent信任评价模型中引入动态学习机制。采用该机制,agent在协作中可以根据环境参数、历史交互信息动态调整信任评价方式,并且在模型中引入陌生人信誉,根据对陌生人熟悉度和可靠度的计算结果处理与陌生人的交互。实验表明,采用该机制,MAS在取得目标奖励的同时,可以动态选择信任评价方式,有效地对目标agent进行评价。