Data collection, speed

The technique was made practical for personnel screening applications by incorporating sequentially switched linear antenna arrays to improve the data collection speed to near real-time rates [ 17,27-31 ]. The linear arrays allowed one axis of the two-dimensional planar aperture to be scanned electronically at very high speed (on the order of several microseconds per element). This reduced total data collection for practical systems to human body is not transparent to millimeter-waves, personnel will need to be inspected from multiple aspects (front and back at a minimum). 

Because of the interest in analyzing intact specimens with the minimum of sample preparation, fluorescence microtomography will likely be a technique used more frequently in the future. Improvements in data collection speed will be needed to make this technique more routinely applicable. 

The use of ultra-high-pressure regimes and/or flow rates in the micro- or nanoliters per minute range imposes unique requirements on LC system hardware, such as pumps, valves, injectors, connecting tubing, column construction, stationary phases, column heating systems, detection flow cells, and the detector s data collecting speed. 

Obviously one should only carry out such fast experiments if the time evolution of the sample is on the same scale. If one deals with slower systems it is better to reduce the data collection speed. 

Detectors in diffraction are typically point detectors or area deteetors. Area detectors enable faster data collection speed increases and the abihty to reduce sample volrrme. 

In the stress relaxation test, the material is subjected to a step strain at time zero (inset. Figure 8.3.5), and the decay in the stress (or modulus) is monitored as a function of time (Figure 8.3.5). At short time, limitations due to electronic hardware can affect the data collection speed and the transducer inertia can affect the torque values, thereby affecting the quality of the data. At long time, the low torque signal and hysteresis of the torque transducer affects the data quality. 

At that time, CARS microscopy was implemented with a sample-scanning scheme [19], so that the data collection speed was principally limited by the slow scanning and by the low photon counting rate that needed to be kept below 5% of the laser repetition rate [18]. The acquisition time for each pixel was several milliseconds, thus a whole image of 512 X 512 pixels usually required more than 10 min. 

Position Sensitive Detectors. By replacing the scintillation detector in a conventional powder diffractometer with a Position Sensitive Detector (PSD), it is possible to speed data collection. For each x-ray photon received a PSD records the angle at which it was detected. Typically, a conventional scintillation detector records x-ray photons in a range of a few hundredths of a degree at a time. A PSD can measure many degrees (in 20) of a powder pattern simultaneously. Thus, for small samples, data collection, which could require hours with a conventional detector, could take minutes or even seconds with a PSD. 

The main advantages of EDS are its speed of data collection the detector s efficiency (both analytical and geometrical) the ease of use its portability and the relative ease of interfacing to existing equipment. 

The federal test procedure for new vehicle certification IS limited to a maximum acceleration rate of 3.3 mph/sccond and a maximum speed of 57 mph (and even that speed is for a veiy short duration). Based upon extensive data collected in Baltimore, Spokane, and Atlanta, more than 8.5 percent of all speeds exceeded 57 mph, and more than 88 percent of trips contained acceleration activity exceeding 4 mph/sec-ond. In fact, more than one-third of the trips monitored included an acceleration rate at some point during the trip of more than 7 mpli/second. Similarly, more than 15 percent of the deceleration activity exceeded -3.5 mph/second. Hence, enrichment events are significant in real-world emissions inventories. 

Analysis type As discussed previously, data-collection analyzers incorporate analysis parameter sets that allow the user to control the data-gathering process. APSs provide the option of selecting either frequency analysis for fixed-speed machinery or orders analysis for variable-speed machinery. 

The major advances in crystallographic methods were both experimental and theoretical. In experimental terms, there was widespread availability of synchrotron data collection resources and the emergence of CCD detectors that dramatically increased the speed at which data could be collected. A particularly important advance was the development of cryocrystallography methods [39] that revolutionized crystallography by making crystals essentially immortal. 

This method is also being used at the Hines VA CSPCC for a number of trials. It appears to be superior to the paper data collection with centralized interactive data entry. It is not time consuming because data are entered with high-speed double-key data entry, which expedites processing of received forms and thus the accumulation of the master database. Another major advantage is that only one person is needed to run the system. 

Various computer software and programs have been developed and used to simplify the transformation, manipulation, and analysis of trial data, to speed up and increase the accuracy of reporting the trial s hndings. If data are collected in a format other than that required by the analysis software, the data must be transformed. There are several data conversion software packages that can be used to transform the collected data from the original format to the analysis format. Examples of these include DBMSCopy and Stat/ Transfer. 

The basic function of the spectrometer is to separate the polychromatic beam of radiation coming from the specimen in order that the intensities of each individual characteristic line can be measured. In principle, the wide variety of instruments (WDXRF and EDXRF types) differ only in the type of source used for excitation, the number of elements which they are able to measure at one time and the speed of data collection. Detectors commonly employed in X-ray spectrometers are usually either a gas-flow proportional counter for heavier elements/soft X-rays (useful range E < 6keV 1.5-50 A), a scintillation counter for lighter elements/hard X-rays (E > 6keV 0.2-2 A) or a solid-state detector (0.5-8 A). 

The advantages of measuring at very low temperatures are well established [4], Because of the increased speed of data collection, it now becomes feasible to consider the use of liquid helium as a cryogen. A prototype open-flow helium cooling device using mainly off-the-shelf components has been developed [3],... 

We have kept the data collection computer and its software simple and economical. The computing power and peripherals needed to provide high quality plotting and data reduction are available on a 32-bit minicomputer that supports a number of our projects. The floppy discs from the data collection process can be read directly into the data reduction computer. Special menus have been set up to facilitate plotting of the data on a high speed color raster display or on a high-quality multicolor pen plotter. 

The mechanistic model developed in the last section is applied to the data collected experimentally. Bubble diameter and bubble velocity calculations were based on the empirical equations obtained from frame-by-frame analysis of high-speed motion pictures taken under the respective operating conditions (Yang et al., 1984c). The equations used are ... 

The high speed of the i-V data collection eliminates vertical and lateral drift of the tip position, and the surface topography and the spatially resolved I- Vcharacteristics arc determined simultaneously at each point in the x scan. 

The changes in a and f> can be determined very rapidly, allowing changes in film thickness and optical properties to be determined in real time, hence the technique can be used to gain kinetic information. The speed of data collection is limited only by the response of the instrument and this may be as low as a few tens of microseconds. 

Input data Wind-speed measurements for 176 locations are used for the simulation covering a time period of one year. The data were collected in 1998, which was an average wind year. The surplus electricity of wind energy is calculated in four... 

A number of synchrotrons (including the National Synchrotron Light Source, New York, the Advanced Light Source, Berkley, and soon the Canadian Light Source, Saskatoon) operate mail-in crystallography services where a scientist can mail in crystals (prefrozen and mounted on loops) and data will be collected, processed (sometimes), and returned. This is becoming a method of choice, as it eliminates the need to travel to a synchrotron and speeds up the data collection procedure at the synchrotron also. 

The axial screw temperature profiles for the screw speeds are shown in Fig. 10.21. These profiles were constructed from the data set shown in Fig. 10.20 by using the data collected at steady state. As shown in this figure, the temperature profile would approximate the model developed by Cox and Fenner [30], but the temperature distribution is more complicated than this simple model. 

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