873 resultados para data acquisition


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The physical meaning and calculation procedures for determining loudness was critically analyzed. Four noise sources were used in comparing the software packages dBFA dBSonic, which were used in the investigation to a public domain code. The purpose of the comparison was to evaluate the validity of the results obtained and to gain an idea of the shortcomings of the relevant standards. A comparison of the results for loudness was computed from various methods, used in the study. Two basic sources of input data such as a sound level meter (SLM) and a 01 dB data acquisition system (DAQ), were available for the comparison. The SLM directly gave 1/3 octave band levels, while the data from the DAQ was filtered to give the results. Five processing methods, including a Visual Basic (VB) program and a VB program adapted from dBFA, were used for the study. It was found that the calculation of loudness from 1/3 octave cannot be separated from the filtering process.

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A closed aquatic ecosystem (CAES) was developed to stud), the effects of microgravity on the function of closed ecosystems aboard the Chinese retrieved satellite and on the spacecraft SHENZHOU-II. These systems housed a small freshwater snail (Bulinus australianus) and an autotrophic green algae (Chlorella pyrenoidosa). The results of the test on the satellite were that the concentration of algae changed little, but that the snails died during the experiments. We then sought to optimize the function of the control system, the cultural conditions and the data acquisition system and carried out an experiment on the spacecraft SHENZHOU-II. Using various sensors to monitor the CAES, real-time data regarding the operation of the CAES in microgravity was acquired. In addition, all on-board Ig centrifuge was included to identify gravity-related factors. It was found that microgravity is the major factor affecting the operation of the CAES in space. The change in biomass of the primary producer during each day in microgravity was larger than that of the control groups. The mean biomass concentration per day in the microgravity group decreased, but that of the control groups increased for several days and then leveled off. Space effects on the biomass of a primary producer may be a result of microgravity effects leading to increasing metabolic rates of the consumer combined with decreases in photosynthesis. (c) 2007 COSPAR. Published by Elsevier Ltd. All rights reserved.

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Cellular behavior is strongly influenced by the architecture and pattern of its interfacing extracellular matrix (ECM). For an artificial culture system which could eventually benefit the translation of scientific findings into therapeutic development, the system should capture the key characteristics of a physiological microenvironment. At the same time, it should also enable standardized, high throughput data acquisition. Since an ECM is composed of different fibrous proteins, studying cellular interaction with individual fibrils will be of physiological relevance. In this study, we employ near-field electrospinning to create ordered patterns of collagenous fibrils of gelatin, based on an acetic acid and ethyl acetate aqueous co-solvent system. Tunable conformations of micro-fibrils were directly deposited onto soft polymeric substrates in a single step. We observe that global topographical features of straight lines, beads-on-strings, and curls are dictated by solution conductivity; whereas the finer details such as the fiber cross-sectional profile are tuned by solution viscosity. Using these fibril constructs as cellular assays, we study EA.hy926 endothelial cells' response to ROCK inhibition, because of ROCK's key role in the regulation of cell shape. The fibril array was shown to modulate the cellular morphology towards a pre-capillary cord-like phenotype, which was otherwise not observed on a flat 2-D substrate. Further facilitated by quantitative analysis of morphological parameters, the fibril platform also provides better dissection in the cells' response to a H1152 ROCK inhibitor. In conclusion, the near-field electrospun fibril constructs provide a more physiologically-relevant platform compared to a featureless 2-D surface, and simultaneously permit statistical single-cell image cytometry using conventional microscopy systems. The patterning approach described here is also expected to form the basics for depositing other protein fibrils, seen among potential applications as culture platforms for drug screening.

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A read-out and data acquisition system for the outputs of multi-channel spectroscopy amplifiers is introduced briefly in this paper.The 16-channel gating integrator/multiplexer developed by us and PXI-DAQ card are used to construct this system.A virtual instrument system for displaying,indicating,measuring and recording of output waveform is accomplished by integrating the PC,hardware,software together flexibly based on the Lab Windows/CVI platform in our read-out and data acquisition system.In this system,...中文文摘:简要介绍一个针对多路谱仪放大器的读出与数据采集方法与系统。该系统基于16通道门积分/选通输出电路和通用PXI-DAQ卡构建。利用Lab Windows/CVI平台构建虚拟仪器,灵活地将计算机、硬件、软件结合起来,设计了一个读出与数据采集系统。在该系统中,一个ADC通道可以面对16个谱仪放大器的输出,有效地提高了系统的集成度,降低了数据采集系统的成本。该设计为利用通用型谱仪放大器构建数百参数的信号读出与数据采集系统提供了一种新的方法。通过实验验证,证明该系统具有智能化、可靠性高、实时性强、成本低等优点。

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A multi-channel gated integrator and PXI based data acquisition system have been developed for nuclear detector arrays with hundreds of detector units. The multi-channel gated integrator can be controlled by a programmable Cl controller. The PXI-DAQ system consists of NI PXI-1033 chassis with several PXI-DAQ cards. The system software has a user-friendly GUI which is written in C language using LabWindows/CVI under Windows XP operating system. The performance of the PXI-DAQ system is very reliable and capable of handling event rate up to 40 kHz. (C) 2010 Elsevier B.V. All rights reserved.

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A dynamic measurement system was developed by the Institute of Modern Physics (IMP) for the dipole prototype of Rapid Cycle Synchrotron (RCS) of China Spallation Neutron Source (CSNS). The repetition frequency of RCS is 25 Hz. The probe is a moving arc searching-coil, and the data acquisition system is based on the dynamic analysis modular of National Instrument. To get the error of high order harmonics of the field at basic frequency, the hardware integrator is replaced by a high speed ADC with software filter and integrator. A series of harmonic coefficients of field are used to express the varieties of dynamic fields in space and time simultaneously. The measurement system has been tested in Institute of High Energy Physics (IHEP), and the property of the dipole prototype of RCS has been measured. Some measurement results and the repeatability of system are illustrated in this paper.

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随着物理实验要求的提高,利用先进的计算机技术来改造现有的物理实验设备具有重要意义。因此,我们设计研制了光谱测量与能级寿命测量数据获取电子学系统。本文全面论述了这一系统的组成结构。本系统由微机进行控制,通过基于Pentium机上工SA总线的接口电路来控制数据采集过程,实现了测量设备的智能化,并具有高速度、高可靠性的特点。配合软件工作可完全实现实验的无人监控。论文第一部分介绍了这个系统开发的背景及意义。第二部分是这个系统的组成和硬件结构、性能。这个系统完成的主要功能是:(1)采集数据并处理;(2)控制外设马达的运动;(3)显示系统的状态。第三部分是调试过程以及针对在调试中出现的各种实际问题提出的解决办法和预防措施。在设计工作完成之后,本系统在兰州近代物理研究所的加速器实验大厅中进行了模拟实验,并采集了部分数据。通过对获取数据的处理,获得了比较满意的结果。在论文的最后一部分中给出了本系统在实际运行后得出的实验结果以及此系统中可待完善之处。

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随着原子核科学技术的发展,无论是对原子核内部特征和规律的研究,或者是对原子核科学技术的应用,都需要对核辐射和原子核所携带的信息进行测量和分析研究。在核电子学测量系统中,核辐射探测器输出信号在经过各种信号处理电路后,通常都要变换成数字信号,再经过数据收集和处理,给出实验的最终结果,因此实验工作的任何进展都要求有相应的数据获取和处理系统的支持。根据实验的实际需求,我们以采集、处理探测器输出的信号为题,开展了一些研究工作,我们先后开展的研究工作包括以下儿个方面:1.激光功率计的变换与显示电路的研制2.基于PCI总线、嵌入8051单片机的计数卡的研制3.数据处理分析软件的设计这三部分的设计工作我们将在论文的第二、第三、第四章分别进行阐述。激光功率计的变换与显示电路把由激光功率计输出的模拟电压量变为数字脉冲输出,并且把该输出脉冲的频率实时定性显示出来。本电路测量精度高,线性好,工作稳定。我们研制开发的计数卡是一种很实用的计数卡,它是一种基于PCI总线,嵌入单片机的高速计数器,最大计数范围为109-1,最高的计数频率为20MHz。该计数卡计数范围宽,计数频率高,具有定时计数、重复计数等功能,可以取代常规的定标器,具有广泛的应用前景。数据处理分析软件包括下位机软件、上位机软件及通讯协议三部分,实现数据的采集与记录,并将读取的数据以Excel电子表格的形式存储,以备查询。下位机的软件采用KeilC编写,上位机软件采用Delphi编写。目前激光功率计的变换与显示电路和计数卡及相应的数据处理软件都设计、调试完成,已经投入使用,获得满意结果,受到好评。

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本文介绍我们最新研制的微功耗核谱数据获取系统。目前,该系统基于微型计算机(IBM PC 486)获取,有待进一步发展成单片机获取系统。该系统具有功能强、功耗低、体积小、重量轻以及抗辐射的特点。为了降低功耗,电路设计中尽量使电路简单化,并选用微功耗、抗辐射的MOS场效应管元件。功率消耗单通道小于2.2w,若做成四通道可少于4W。 本系统以脉冲幅度分析方式获取数据,软件采用Turbo C 2.0编写,界面友好,操作方便。

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在海洋学研究、海洋生产和工程建设应用中,经常需要对特定区域的海水参数进行长期、定点、实时的垂直剖面测量。锚系浮标和潜标是海洋监测网中最普遍采用的搭载平台之一,它们主要用于海洋环境定点监测。海洋浮标在研究海洋和大气的相互作用及全球气候变化、预报全球性和地区性海洋灾害、海洋污染监测、卫星遥感数据真实性校验、以及作为平台用于水声通讯和水下定位等方面发挥了重要作用,其缺点在于隐蔽性和安全性较差。潜标监测平台由于其主浮体安装在水下50-100米,具有良好的隐蔽性和安全性,在构建海洋立体监测系统中有较好的应用,但由于它总是隐藏在海表面以下,所搭载的测量传感器的种类有限,数据实时传送困难,从某种程度上也限制了其应用。 节能型自治式多功能海洋环境监测系统将定点锚泊潜标和浮标技术相结合,并创新性的融进了节能技术和自动防触碰功能,利用简约的传动储能节能技术,以C8051F340单片机为核心控制芯片,设计了低功耗、高可靠的数据采集控制存储系统的硬件电路和软件系统,使系统不但能够完成锚泊区域海表面水文参数的测量和数据传送,同时依靠单一的传感器组能够完成深达50米以上的水体次表层海洋要素的连续垂直剖面观测。系统利用SD卡实现了对海洋要素采集数据的实时存储和传送。低功耗、高可靠的数据采集控制存储系统的设计为海洋测量仪器实现智能化控制奠定了基础,提升了人类对海洋进行持续现场监测的能力。

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论文设计研制了行为辅助机器人验证平台,以此平台为基础可以针对行为辅助机器人进行力控制研究。针对机器人力控制的实际要求,设计了行为辅助机器人柔性关节结构,辨识了系统参数。基于QNX实时操作系统设计了控制系统软件。机器人控制系统软件主要包括传感器数据采集和控制算法两部分,可以满足柔性关节控制需求。

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提出一种基于CAN总线,面向实时控制任务的高速数据采集存储方法.该方法将数据实时采集、系统实时控制、数据存储与显示分配在相互独立的处理单元中实现,处理单元之间通过独立的CAN网络进行通信.该数据采集方法解决了数据实时采集与系统实时控制之间的矛盾.利用队列技术,该方法解决了数据存储与数据实时显示之间的矛盾.该数据采集存储方法已成功应用到某大型仿真系统中.

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在偏振耦合测试仪的PCI接口数据采集系统中,现场可编程门阵列(FieldProgramableGateArray)实现了对模/数器件的控制功能,同时完成了与PCI总线控制器间的数据接口功能。应用自顶向下的设计思想,完成了FPGA内部的逻辑设计,并对其逻辑功能进行了仿真验证,给出了FPGA数据采集时的测试时序图。应用FPGA实现的数据采集系统可以检测出偏振耦合检测仪中的微弱干涉光信号。

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介绍了基于工业以太网的载人潜水器的数据采集与监控系统。简要地阐述了载人潜水器的重要性。详细地描述了该系统的硬件结构及各智能节点的特点,并对系统中各层所实现的功能进行了详细的介绍。目前,该系统已在实验室进行了实验,实验效果良好。

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本文主要介绍用于图象数据处理的 CCD-微机系统。该系统使用电荷耦合器件(CCD)作为传感器,并与微型计算机连接,进行图象数据的采集和处理。系统还包括有光学系统、CCD 驱动控制线路、计算机 I/O 接口和应用软件。数据采集程序用汇编语言编写,数据处理和打印程序用 BASIC 语言编写,整个软件用BASIC 语言编写的程序管理。应用该系统曾对静止和运动物体尺寸进行过非接触测量,重复性很好。