Continuous duty cycle

The Milagro detector s large field of view and continuous duty cycle make it an ideal instrument for the discovery of previously unknown sources. Recent publications cover topics including detection of the Crab Nebula[l], limits on TeV emission from GRB [2] and a TeV all-sky survey of the northern celestial hemisphere[3]. Recently we have presented papers on the detection of diffuse TeV emission from the Galactic plane[4], limits on TeV emission from satellite detected GRB[5], a study of nearby AGN[6] and limits on relic neutralino annihilation derived from TeV flux limits from the sun[7]. The focus of this paper is the search for extended sources of TeV gamma rays with the Milagro detector. 

The resistance units, when used only for starting purpose, are in the circuit for only a short time and are thus short-time rated. However, when they are employed for speed control, braking or plugging operations, in addition to the starting duty, they may be rated for continuous duty. The resistance units are thus classified according to their duty demand, i.e. number of operations per hour (c/h). See Chapter 3 on the duty cycle. 

This output coixesponds to a continuous duty of drive. It must be suitably corrected for the duty cycle the motor has to perform (see equation (3,11)), i.e. 

Duty cycles Continuous duty (CMR) (S ) Periodic duties Factor of inertia (FI) Pleating and cooling characteristic curves Drawing the thermal curves Rating of short motors Equivalent output of short time duties Shock loading and use of a flywheel... 

As explained above, the continuous radioactive source used in our IMS also produces small, and sometimes troublesome, amounts of impurities within the ion source. In an effort to eliminate this problem, we are presently exploring the use of other source designs by which less radiation damage is done to the source gas. One of these alternative ionization methods is based on the photoemission of electrons from the back side of a gold foil. This ion source offers an attractive advantage for the study of negative IM reactions in that it can be shut off during most of the IMS duty cycle. 

Sampling with fiber optic sensors can be continuous if needed otherwise they can be operated discontinuously, with a lower duty cycle. These sensors could be used for laboratory-based or in situ applications. The cost of instrumentation for fiber optic systems should be 25,000 to 50,000. Sensors would need to be replaced periodically (several weeks to many months), depending upon their design. Sensors using fiber optic probes will be available within 5 years for some applications and within 10 years for some others. Sensors for pH, C02, and 02 are in development now new sensors should be capable of measuring from high concentrations down to 1 part per million for ions and organic materials. Basic research is still required for specific applications. 

The main factor affecting orthogonal TOF is the duty cycle. This is how often ions can be pulsed into the TOF analyzer. When waiting between extraction pulses, ions are being wasted (they pass through the extraction region and are lost) and so the ideal is obviously to have this process as near to continuous as possible. The factor limiting the duty cycle is the time taken by the slowest... 

The obvious benefit of the quadrupole ion trap is that it is an ion storage device. Therefore, ions can be both accumulated and stored for extended periods. Accumulation can occur over a continuous ionization event or over multiple pulsed ionization periods. When used with pulsed ionization sources, duty cycle, defined in terms of sample utilization, can be as high as 100%. Because a broad range of atomic ions can be stored simultaneously, the quadrupole ion trap is a promising analyzer for transient peak analysis. 

Orthogonal injection provides a high-efficiency interface for sampling ions from continuous beam to a TOF analyser. The TOF analyser allows simultaneous transmission of all ions and therefore all the ions formed are analysed. However, the duty cycle is far from 100 % for the oa-TOF spectrometer and it is lower than for the TOF spectrometer. This is due to the orthogonal accelerator that samples to the analyser only a part of the ions produced in the source. The duty cycle, despite this fact, is between 5 and 50 %. This is a considerable improvement over the conventional techniques described for coupling a continuous source to a TOF spectrometer. 

Sonophoresis has employed three distinct categories of US high-frequency or diagnostic US (2-10 MHz), mid-frequency or therapeutic US (0.7-3 MHz), and low-frequency US (5-100 kHz). It appears, from a general overview of the literature, that the efficiency of US-mediated drug delivery depends on several factors, including US frequency, intensity (i.e., power per unit area), continuous versus pulsed mode, duty cycle, duration, coupling medium, and so on. The fact that very few studies have used common values for some or any of these parameters almost certainly accounts for the different and sometimes contradictory results in the public domain. 

Amplitude of ultrasound waves can be represented in terms of peak wave pressure (in Pascals) or in terms of intensity (in the units of W/cm ). Ultrasound can be applied either continuously or in a pulsed manner. In the latter case, an additional parameter, duty cycle, is required to characterize ultrasound application. Duty cycle is the fraction of time for which ultrasound is ON. 

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