The Data Collection Period

HyperChem runs the molecular dynamics trajectory, averaging and analyzing a trajectory and creating the Cartesian coordinates and velocities. The period for reporting these coordinates and velocities is the data collection period At2. It is a multiple of the basic time step, At2 = n2 Atj, and is also referred to as a data step. The value n2 is set in the Molecular Dynamics options dialog box. 

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At, etc. The Snapshot period is specified 111 the Snapshot dialog bo by n, data steps, i.e. as a ni ii Itiple of the data collection period, At4 = n4 i3t2. 

TlyperCi hem updates the screen diirin g a trajectory at regular in ter-vals so yon can visiiali/e the irajectory. Since this screen update may slow down a trajectory If it occurs too frequently, yon c.an specify the duration of the Screen Refresh period At.,. The screen updates at ilines tQ, Iq + Atj, to + 2Atj, etc. The Screen Refresh period is specified in the Molecular Dynamics options dialog box by n 5 data steps, i.e. as a m iiliiplc of the data collection period, At5 = n 5 At2-... 

It may have been possible to implement very obvious waste-reduction measures already, before embarking on obtaining a material balance (even as early as at the end of Phase I). You should now consider the material balance information in conjunction with visual observations made during the data-collection period, to pinpoint areas or operations where simple adjustments in procedure could greatly improve the efficiency of the process by reducing unnecessary losses. 

When existing factories are being examined, the floor areas occupied by the various items of equipment can be measured on site during the data-collection period. It is important to consider and include the equipment outline (maximum travels), space for maintenance activity, operator movement and the handling of material and workpieces. In many cases, the space needed for handling exceeds that required accommodating the operative part of the equipment. Aisle space is also needed for through-shop movement. 

Even in the nominal absence of laser fluctuations or other imagedegrading aberrations, the number of photons that hit the detector during the data collection period of the image (i.e., the exposure time for a CCD image or the pixel dwell time for a confocal image) will contain considerable noise. The photon count x follows a Poisson distribution (Fig. 7.7A) with mean value fi as... 

Figure 7.3.1.8 Instrumental configuration for mass-limited characterization by microcoil NMR. The analyte is bracketed on both sides by plugs of an immiscible perfluorinated organic liquid and sealed with an optically curable glue to prevent dilution during the data-collection period...

Despite the short half-time of Zn-69m which limited the data collection period such that the model could only analyze the rapid processes of zinc metabolism (approximately 10% of total body zinc), a number of fundamental steady state parameters were derived as shown In Table I. 

Figure 3. This kinetic model for zinc in humans was based on averaged data obtained following oral and i.v. administration of Zn to 17 patients with abnormalities of taste and smell. The compartmental model used all kinetic data from Zn activity in plasma, red blood cells, urine, liver, and thigh as well as stable zinc parameters, including dietary intake, serum, and urinary concentration. The SAAM27 computer program was used to obtain the simplest set of mathematical relationships that would satisfy the data characteristics for each measurement time in the study and remain consistent with accepted concepts of zinc metabolism. Although the short physical half-life of Zn limited the data collection period, this model allowed for analysis of the rapid phases of zinc metabolism (about 10% of total body zinc) and derivation of a number of fundamental steady state...

Intensity standards (008).(660).(-6 6 0) measured c er I hour of. -riiy e.xposure lime. Over the data collection period no net decrease in inlcnsiiy nas obscoed. 

The SSSB is deployed in the Atlantic Ocean approximately 40 km northeast of Cape Hatteras (Case 1413) at 35° 26.16 N, 75° 2.90 W and retrieved at 35° 24 N, 75° 4 W. The data collection period is from 13 59 29.14 (t = 0) to 16 09 22.03 (t =7783.15s) UTC. The data for the first 14 minutes or so are onboard the research vessel and not used. On this day, two long internal wave bands several kilometres long and approximately 2 to 4 kilometres apart are spotted on the water surface. The buoy is released into water at 14 13 UTC. The sky is partly cloudy. At 14 49 (t 3000 s) the ship is in a large dark cloudy area. The buoy records a sharp drop in the ambient light at t >2500 s. The dual surface slick bands are visible throughout the morning. The buoy obviously crosses one of them at t 3100 s when a dip of 0.1°C water temperatures is recorded (Fig. lb). Visual confirmation of this encounter is not available due to the large distance between the ship and the buoy. However, similar surface temperature drops (from Jim Edson s onboard met-sensor display) occur when ship crosses slick bands in a few other occasions. 

It is possible to extend the data collection period (and the delay period) to allow all of the carbons in a molecule to relax however, this is usually done only in special cases. Since repetitive scans are used in spectra, the increased acquisition time means that it would simply take too long to measure a complete spectrum with a reasonable signal-to-noise ratio. 

Moves towards an apparently systematic and rigorous approach to health and safety had already begun during the data collection period for this research. This approach emerged in response to a variety of influences, some of which were specific to the industry and others of which were general and extended beyond the railway industry. The specific events were the aftermath of the King s Cross and Clapham Junction accidents, which caused the whole railway industry to reappraise completely its approach to health and safety (see Ch. 3). 

The data collection model above-mentioned allowed the collection of 53 variables. Fifty eight accidents were recorded. The surveys were answered voluntarily and data processing act in accordance with the Portuguese legislation on the protection of personal data, ensuring its confidentiality. The data collection period was between March and May of 2014, corresponding to a period of accidents at work from January 2013 to March 2014 (15 months—reference period). 

Figure 11.19 illustrates the fluctuations in pipe-to-soil potentials for a pipeline in close proximity to an electrified rail transit system. Typically a number of trains would have passed this monitoring point during the data collection period in Fig. 11.19. Positive potential excursions associated with current discharge at the measuring point and negative potential transients related to current pickup are evident. At greater distances from the stray current source the potential profile is significantly more stable, as indicated by the second potential trace in Fig. 11.19.

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