基于蓝牙传输的脉搏信号检测系统的设计与实现

设计基于无线蓝牙传输的脉搏信号检测系统,系统包括PVDF脉搏传感器、信号调理电路、数据采集电路、蓝牙无线传输模块和上位机数据接收显示模块.实验结果表明,该系统能够对人体的脉搏信号进行实时采集,将数据通过蓝牙无线发送到由J2ME语言编程的手机中,接收到的脉搏信号可在手机上显示波形,并可进一步对信号进行处理,进而实现远程监护.     

基于单片机的室内甲醛测试系统的设计

本文是利用单片机来实现的室内甲醛浓度的测试,设计的总体思路是接收信号-信号转换-数据采集-存储-显示。首先是利用甲醛传感器将气体转换为电信号。当空气被其内部的采样系统吸收后,产生一个与甲醛浓度成正比的电流,此电流经过甲醛模块的信号调理,经电流电压转换器RCV420转换成0～5V的电压,该电压经过模数转换器5G14433进行数据采集,将模拟信号转换成数字信号,然后与8051单片机相连,将转换后的结果存储在单片机中,显示器上直接显示测试结果,即甲醛浓度。本设计基本实现了单片机控制电路,传感器输出范围要明确以及     

能量释放型旋转轴定位装置

日前我校“能量释放型旋转轴定位装置”技术被授予实用新型专利 ,该装置用于机械加工及自动设备的旋转轴定位 ,它的定位控制电路由空转信号门电路、空转圈数计数电路、定位信号门电路、定位信号延时电路组成 ,定位控制传感器包括A、B两个传感器 ,空转信号门电路的输入端与传感器B相连 ,输出端分别与空转圈数计数电路和电机交流失电继电器相接 ,定位信号门电路的输入端还分别与传感器A、定位信号延时电路的输出端相接 ,输出端接定位信号延时电路 本专利技术的优点在于采用切断电源后控制系统不立即强制进行大电流整流反转制动 ,而是待旋转…     

基于虚拟仪器的心功能检测系统的设计

设计了一种基于虚拟仪器的具有心电采集和踏车控制功能的心功能检测系统.系统采用自行设计的数据采集卡来实现心电数据的安全测量和输出控制指令.数据采集卡由心电信号放大电路、信号采集电路、踏车控制电路组成,通过USB接口与PC机相连.系统软件采用LabVIEW编程语言,可实现数据库管理、心电波形显示、心电特征点分析、实时心率显示、ST段识别、踏车控制、数据即时存储、波形回放以及打印诊断结果等功能.     

基于脉宽调制的程控恒流源设计

详细介绍了程控恒流源电路的设计,分析了电路原理.程控恒流源电路是由单片机片内定时器输出的脉宽调制信号来控制,并用该电压控制恒流源产生可控电流.通过单片机的键盘接口对输出电流进行设定,实现输出电流的连续调节及电流的动态测量.由MSP430单片机及其外围电路经过巧妙的设计构成,电路的性能十分理想.     

LED闪光灯电源的研究与设计

本设计以STC12LE5201AD单片机作为闪光灯电源的控制核心.采用电流斩波电路将3 V输入电压升高给控制器供电.通过电阻反馈电流、单片机输出PWM、场效应管开关控制电路、电流恒流源控制等方式有效的恒定输出电流.实验表明,该变换器能将电池电能转化为恒流输出、同时实现连续和脉冲两种输出模式、电流档位的选择、输出电压限压保护和过载报警功能.系统输出相对误差小于2%,效率达到91.8%,能够满足恒流稳压电源的要求.     

一种基于PC/104总线的多路交流电源记录仪的研制

针对双路交流电源的电压和电流信号波形长时间记录和监测的需求,提出了一种基于PC/104总线的多路交流电源记录仪的设计思想,研制了多通道交流电压和电流信号调理电路和A/D转换采集模块的硬件以及系统控制软件,实现了多路信号的数据采集、波形实时显示、长时间数据存储、故障分析监测等功能。     

基于巨磁阻传感器的电源逆变器过流保护电路设计

针对电源逆变器中的过流保护问题,设计了由巨磁阻传感器组成的电源逆变器过流保护电路系统,该系统采用巨磁阻传感器实时采集电源电流,巨磁阻传感器根据电磁感应原理,将交变电流转换为相应的电压信号。通过监控电路实现电压信号的放大和处理,DSP和开关控制电路用来实现电路的开通与关断。实验结果表明该电路可以实现过流保护功能,并且可靠性好、灵敏度高。     

光伏并网发电模拟系统

此光伏并网发电模拟系统采用MSP430F449为核心控制芯片,采用全桥逆变电路作为DC-AC的核心电路,通过控制BUCK电路实现MPPT最大功率点跟踪,单片机发送PWM信号控制逆变电路产生正负交替的工频交流信号.逆变电源具备各种保护功能,如输入直流极性接反保护,交流输出短路保护、过热、电流电压过载保护等.利用逻辑器件输出的pwm波形控制逆变电路,输出含有较多的谐波分量,因此要加滤波输出正弦波电流.     

晶闸管触发器Proteus仿真设计

本仿真通过AT89C2051单片机作为主控制芯片,用晶闸管作为主要开关器件.设计的目标是保持输出的直流电压稳定,输出电压纹波小,交流输出测电流THD较低,性能可靠.系统主要电路包括:三相桥式全控整流电路,同步信号取样电路、单片机控制电路、晶闸管触发电路.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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An on-line scaling method for improving scalability of a database cluster

The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.     

An improved R-tree based on childnode''s probability

R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).     

Integrating GIS Web services based on mediating architecture

The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.     

Tracking data management using topology of moving object database system for moving object constrained trajectory in LBS application

Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.