Data Acquisition Stage Research Articles

Data taking system for the NEMO experiment

A four-floors prototype of the NEMO towers has been successfully deployed off the Sicily coast in December 2006. The aim of this contribution is to give an overview of the NEMO electronic system and to explain the different stages of data acquisition and transport.The underwater electronics sample signals from photomultipliers and acquire slow-control data both from oceanographic instruments and dedicated sensors, allowing to monitor the operational conditions of the apparatus.The whole data are sent to the laboratory through a fully bi-directional fiber optic link. On-shore the data are received by dedicated boards that distribute them to first-level trigger and to the slow-control system.The NEMO data acquisition/transmission electronic system will be described, properties of acquired signals and of data flow will be discussed.

An Economical Magnetocardiogram System Based on High-TcSQUIDs

An economical magnetocardiogram (MCG) system is built in ourlaboratory. It mainly consists of a MCG data acquisition stage equippedwith two high-Tc superconducting quantum interferencedevice (SQUID) magnetometers, a data processing stage with digitalfiltering and a one-layer μ-metal magnetically shielded room inconjunction with a high-Tc SQUID based active compensation.Experimental results show that a noise level of pico-tesla in MCGprofiles, which is necessary for clinical applications, may be achievedwith the system. Moreover, stable and convenient operations of thesystem are demonstrated with simulating MCG measurements.

Vibration based Fault Diagnosis of induction Motor

All types of rotating machines even new ones generate some level of vibrations. Small level of machine vibration is acceptable, however higher level and increasing trends are symptoms of abnormal machine performance. Therefore, machine vibration analysis becomes one of the important tools for machine fault identification. This paper presents an integrated pattern recognition method based on Euclidean distance measure for vibration diagnostic of machine health. The overall process is subdivided into stages of data acquisition, preprocessing, feature extraction and calculation of distance index. A computerized on-line monitoring system has been developed to record the frame vibrations, temperature, speed, line voltages and line currents from a three-phase induction motor for different operating conditions. The proposed method is suitable for both off-line and online applications. The method has been successfully tested for a large number of vibration data collected from the set of five identical test motors under different operating conditions. The test results establish the accuracy, effectiveness and reliability of the method.

Unlocking the spatial dimension: digital technologies and the future of geoscience fieldwork

The development of affordable digital technologies that allow the collection and analysis of georeferenced field data represents one of the most significant changes in field-based geoscientific study since the invention of the geological map. Digital methods make it easier to re-use pre-existing data (e.g. previous field data, geophysical survey, satellite images) during renewed phases of fieldwork. Increased spatial accuracy from satellite and laser positioning systems provides access to geostatistical and geospatial analyses that can inform hypothesis testing during fieldwork. High-resolution geomatic surveys, including laser scanning methods, allow 3D photorealistic outcrop images to be captured and interpreted using novel visualization and analysis methods. In addition, better data management on projects is possible using geospatially referenced databases that match agreed international data standards. Collectively, the new techniques allow 3D models of geological architectures to be constructed directly from field data in ways that are more robust compared with the abstract models constructed traditionally by geoscientists. This development will permit explicit information on uncertainty to be carried forward from field data to the final product. Current work is focused upon the development and implementation of a more streamlined digital workflow from the initial data acquisition stage to the final project output.

Computer-Based Assessment of Pre-assigned Individual Education Plans in Special Education

Abstract — Assessment of IEP (Individual Education Plan) is an important stage in the area of special education. This paper deals with this problem by introducing computer software which process the data gathered from application of IEP. The software is intended to be used by special education institution in Turkey and allows assessment of school and family trainings. The software has a user friendly interface and its design includes graphical developer tools. Keywords — Disabled individual, software for education, assessment of education, special education. I. I NTRODUCTION SSESSMENT of an IEP is very important for determining whether the progress has been satisfactory or not. Additionally, if the educator knows the strengths and weaknesses of a disabled person, he or she will be able to use this knowledge base to make adjustments for further stages of the program. The use of computer based technologies for assessing individual plans certainly reduces educator time that would be spent for this purpose. On the other hand, information technologies minimize human errors in management, data entry and data processing. This would prevent the education plan from progressing inaccurately. One of the most important assessment criteria in the education of disabled individual is to determine the time it takes to manage a behavior [1]. Another important factor is the collaboration between parent and school. The software that we introduce here has been designed to handle all major data acquisition stage and processing problems of assessing IEP in special education. Since the main motivation is to provide assistance to educators, all interfaces in the software are designed to be graphical visual components are also extensively used. These design and implementation elements create a user friendly environment which renders the software easy to apply in a vast range of disability cases. Reporting capabilities are also available for producing assessment reports about the outcomes of an education plan. Reports can be prepared by the family, by the school and comparatively. This is the fundamental step in the assessment of an IEP. II. R

Bidirectional frequency-domain digital filtering to simultaneously improve temperature resolution and eliminate spatial inaccuracy of a distributed temperature sensor

This article discusses a digital filtering technique to improve the temperature resolution of a Raman fiber optic distributed temperature sensor. A frequency-domain digital filtering algorithm has been used for this typically time-domain task to show that by reducing the effect of noise introduced by analog electronics and the quantization noise of the analog-to-digital converter in the detection and data acquisition stages, superior temperature resolution is achievable. An important feature of the filtering scheme used is that no spatial inaccuracy is introduced into the ranging of hot zones, despite the highly nonlinear phase response of the filter. Digital filtering used for postprocessing of data shows clearly and unambiguously a temperature resolution of 5 K in the present setting of our experiment, with the possibility of much greater improvement. Merely using analog signal conditioning does not provide the same clarity and uniqueness in temperature resolution and spatial location that digital filtering offers. This digital filtering scheme offers greater flexibility and versatility than mere signal-averaging approaches to improve the SNR of such systems. The filter's ability to reject deterministic interfering frequencies of appreciable energy content is also demonstrated by simulating such frequencies of much greater energy than the actual signal.

Studying the functional genomics of stress responses in loblolly pine with the Expresso microarray experiment management system

Conception, design, and implementation of cDNA microarray experiments present a variety of bioinformatics challenges for biologists and computational scientists. The multiple stages of data acquisition and analysis have motivated the design of Expresso, a system for microarray experiment management. Salient aspects of Expresso include support for clone replication and randomized placement; automatic gridding, extraction of expression data from each spot, and quality monitoring; flexible methods of combining data from individual spots into information about clones and functional categories; and the use of inductive logic programming for higher-level data analysis and mining. The development of Expresso is occurring in parallel with several generations of microarray experiments aimed at elucidating genomic responses to drought stress in loblolly pine seedlings. The current experimental design incorporates 384 pine cDNAs replicated and randomly placed in two specific microarray layouts. We describe the design of Expresso as well as results of analysis with Expresso that suggest the importance of molecular chaperones and membrane transport proteins in mechanisms conferring successful adaptation to long-term drought stress.

Using CCD’s in Introductory-Level College Astronomy Laboratories

Our university recently purchased a liquid-nitrogen-cooled CCD camera system (from Photometrics Ltd., Tucson, Arizona) which has been installed on our campus’ 40-cm multiple access (Cassegrain/Newtonian) telescope. Images are reduced online at the observatory using Photometrics’ microcomputer-based analysis software package, which includes operations for standard data acquisition and initial stages of data reduction — including corrections for bias, dark current, and flat fielding. Images are displayed on a 256-level-gray-scale black and white monitor. Additional post-processing can be done either on the CCD system’s computer at the observatory or on IBM-AT/PC’s located both at the observatory and in the laboratory.

Acquiring and Analyzing Enzyme Kinetics Data Using Apple Microcomputers

The evolutionarv process, which has placed microcomputers in the science classrooms and laboratories of secondary schools, is elaborate enough to mystify even Charles Darwin. From their early appearances as administrative tools, computers soon migrated down the hallways to the math classrooms. In many instances they still reside in these hallowed bastions. Enterprising science teachers eventually began to encroach with sheets of numbers from lab experiments and, with bright-eyed students in tow, sought the answers that only the computer could provide. Our early science programs were comparatively crude. Many were simulations, and there was a paucity of interactive laboratory experiences which were capable of demonstrating the true versatility of the devices. Furthermore, because of the fear of placing the computer in the laboratory and having something spilled on it, it often functioned as the end-product of a lab experience. We failed to recognize and develop the computer's potential as a laboratory instrument, instead concentrating solely on its ability to crunch numbers from laboratory data. Fortunately, hardware and software developers and administrators began to realize the wide range of computerized instructional applications, and programs were developed in all disciplines to involve the computer in every stage of data acquisition and analysis. In recent years, and with an increasing frequency, science departments have obtained their own machines, not only for tutorials and simulations, but for laboratory-oriented exercises. Physicists and chemists led the way. Only in the last few years have we begun to see a wider variety of such applications adapted to the biology lab. The applications described in the following pages illustrate how to use a microcomputer in acquiring data in a lab exercise, as well as with the subsequent analysis of experimental data. In these experiments, the computer is used first as a colorimeter to monitor an enzyme-mediated reaction under varied laboratory conditions and finally as a tool for data analysis and presentation. Since the machine is in the lab, it tends to be viewed as just another instrument, and its readouts are as useful (but not necessarily more meaningful than) as a pH meter or a laboratory balance. It also permits you to accomplish teaching objectives that are more related to enzymology and physiology than computer science without sacrificing the advantage of the computer's capabilities.

Interactive calibration by a recursive generalized standard addition method

The generalized standard addition method (GSAM) has recently been introduced for calibration to avoid matrix effects and many interferences. In GSAM, all additions and measurements precede the calculations of the K matrix (sensitivities of all analytes at all sensors_ and the analyte concentration. A recursive version of GSAM is presented here. Some new powerful properties are added to the method: (1) on-line checking of the validity of the linear model during the data acquisition stage, (2) simultaneous evaluation of the value and precision of the elements of the K matrix during the additions, and (3) access to an on-line interactive calibration, terminating the addition when the precision is within the desired limits or a deficiency in the model has been detected. The method is demonstrated for spectrophotometric measurements of copper and nickel in the presence of EDTA.

Ct Image Noise and Resolution Behavior in Rc Filter-Based Projection Data Acquisition

This paper deals with the image noise behavior due to photon fluctuation in a CT system based on RC low-pass filter for projection data acquisition. The system configuration considered consists of a stationary detector ring and a rotating x-ray source with convolution-based detector fan image reconstruction. The current generated in individual detectors by transmitted photons during x-ray source rotation is fed into a RC filter and its output is sampled at regular time intervals matched to a basic spatial sampling distance. A projection ray sample is formed by either one or multiple time samples depending upon scan speed. An analytical model of photon noise propagation has been established for this system that characterizes its noise behavior and compares the behavior to the case with active integrators. In general, RC sampling introduces positive correlation between basic time samples, and in turn, between projection samples. This results in varying noise behavior for different scan speeds under a constant dose. The noise behavior is also affected by the reconstruction filters through the positive or negative correlations, which depend on the filter coefficients. Basically, it acts as a smoothing hardware filter which suppresses high frequency noise at an early stage of data acquisition. The impact of RC filtering on spatial resolution is also mentioned.

Time Domain Analysis of Machinery Vibration Signals Using Digital Techniques

The design and implementation of a general purpose processing system to analyze machinery vibration signals in the time domain are presented. The system comprises a data acquisition stage, where analog signals having a maximum frequency content up to 4 kHz and a dynamic range up to 72 dB, are converted into digital form and a processing stage, where modular software algorithms are employed to perform specific operations in an interactive environment. Processing capabilities encompass scaling, integration and the computation of statistical parameters such as means, RMS, standard deviation, maximum and minimum values. The input signal dynamic range and maximum frequency content are shown to be the governing criteria in the design and performance of the analysis system. The influence of hardware precision level and sampling rate on the overall accuracy of the obtained results is illustrated by digitizing standard waveforms under different processing parameters. Extraneous components introduced at the digitization and integration stages are identified and eliminated by employing a versatile digital filter algorithm. The performance of the system in processing acceleration signals from a 3 HP, 14000 RPM internal combustion engine is demonstrated and the different application aspects of such a facility in the machinery maintenance field are outlined.

ADVANTAGES OF ENHANCED DATA LOGGING

Rapid technologic evolution in the period from about 1955 to 1966 has been followed by considerable developments in exploration techniques. In recent years sophisticated data gathering and processing systems in seismic, gravity and magnetic methods, and in wireline logging, have become routine.The validity of interpretations drawn from such data is critically dependent on the care exercised at the data acquisition stage. Because of generally large subsequent processing costs, there is now considerable emphasis on in-field verification of acquisition procedures by highly experienced explorationists.A notable exception generally occurs during the drilling stages of an exploration programme. At present, such data acquisition is generally only carried out on relatively high cost offshore operations where it was first employed for safety reasons. However, geologists of limited experience generally still are given the responsibility of on-site verification of data.It is possible now to monitor fully and digitally record all data, control and optimize drilling parameters and economics, and, in so doing, obtain data which may subsequently be used as basic input to more complete section evaluation.Tangible benefits arise in the following areas : (a) increased drilling efficiencies generally lead to a significant reduction in total cost per foot; (b) substantial improvements in primary and secondary safety during drilling.Intangible benefits which may arise include : (a) direct interpretation of wireline logs and drilling parameter logs to yield quantitative source richness (TOC) and maturation (LOM) of shales; (b) improved interpretation of reservoir properties to allow better prediction of ultimate performance and superior design of stimulation programmes.

Computer-based full scale fatigue testing

Computer-based methods can help to ease the difficulties of realistic full-scale testing by unravelling some of the complexities of multi-channel service loading simulation during the stages of data acquisition, data analysis and test rig control. The potential of these methods is illustrated by a simulated gun firing test — an extreme example which requires the facilities of three widely differing computer systems to carry out full-scale endurance tests.