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System functions

Two molecules of vitamin A are formed from one molecule of -carotene. Vitamin A crystallizes in pale yellow needles m.p. 64 C. It is optically inactive. It is unstable in solution when heated in air, but comparatively stable without aeration. Vitamin A is manufactured by extraction from fish-liver oils and by synthesis from / -ionone. The role of vitamin A in vision seems to be different from its systemic function. See also relincne and rhodopsin. [Pg.422]

Physical separation between eddy current functions and system functions, so that the system requirements (encoders amount, trigger specifications, robot control) can be changed without influence on the eddy current modules. [Pg.277]

Additionally, there are a number of useful electrochemical reactions for desulfurization processes (185). Solar—thermal effusional separation of hydrogen from H2S has been proposed (188). The use of microporous Vicor membranes has been proposed to effect the separation of H2 from H2S at 1000°C. These membrane systems function on the principle of upsetting equiUbrium, resulting in a twofold increase in yield over equiUbrium amounts. [Pg.428]

NT has been impHcated in neuroendocrine function, thermal and circadian regulation, cardiovascular and digestive system function, nociception, and in psychoses as a DA modulator. [Pg.563]

There exists a form of energy, known as internal energy, which for. systems at internal equilibrium is an intrinsic propei ty of the. system, functionally related to its characteristic coordinates. [Pg.513]

There exists a propei ty called entropy, which for systems at internal equilihnum Is an intnnsic propeity of the system, functionally related to the measurable coordinates which characterize the system. For reversible processes, changes in this propeity may be calculated by the equation ... [Pg.514]

FIG. 29-44 Tiirb oexpander system functioning as a refrigeration machine. [Pg.2520]

The region of unreliable reaction at use of created test-tools for visual detection of nitroxoline has been studied. The distribution of frequencies of the detection in region of unreliable reaction for system with Cu [Fe(CN)g] the best fit to the function of normal distribution, for other systems - function Weibulle. A detection limit (c J and other characteristics of test-systems are reduced in the table ... [Pg.325]

The mammalian and avian immune systems function similarly both incorporate humoral and cell-mediated cytotoxic mechanisms, " and are thought to share a 160m year old relationship with the reptilian immune system. The immune system of mammals shows sexual dimorphism " a greater immune response is normally observed in females, which has been attributed to differences in steroid hormone concentration. In the toad Bufo regularis, sexual dimorphism of the immune system is also apparent. ... [Pg.73]

Same sensor used for basic process control system and safety instrumented system. Failure of sensor leads to loss of control system and safety system functionality. [Pg.113]

The most straightforward way of proof testing the equipment would be to reproduce site conditions completely. Under such conditions, the testing would easily establish if the compressor performance requirements are met and if the driver and support systems function as intended and are adequate for the purpose. [Pg.407]

EPRI NP-5664 is a study based on interviews of personnel at 10 utilities and 15 NRC personnel regarding the usefulness of PSA (they use the term PRA - probabilistic risk assessment). The general utility motivation for using PSA is to demonstrate an acceptably low level of risk to the NRC. Some utilities applied PSA to individual systems, functions, or issues. These smaller [ir(>grams served to train a PSA cadre and introduce PSA to other utility personnel and management. [Pg.402]

E-3, evaluate each of your models to determine the probability of this system functioning on demand. Calculate the Bimbaum, Inspection and Risk Achievement Worth Ratio for each of the components using which ever model you prefer. (Once you get the cutsets, it does not matter which model was used as long as it is a correct system model.)... [Pg.497]

It also specifies data requirements, assumptions, limitations, eventual type of critical review, and the report requirements. For example, a study could be done to select between one of two materials when developing a dust transport container for a baghouse filter. The intended audience may be the designers, the results being used to indicate which one of the two materials provides the lowest environmental impact. The system function may be to transport dust from the baghouse filter to a landfill site, and the functional unit may be one metric ton or m of dust. The system boundaries may be described by considering which processes are included and which are outside the system limits. [Pg.1359]

From a reliability engineering perspective, error can be defined by analogy with hardware reliability as "The likelihood that the human fails to provide a required system function when called upon to provide that fimction, within a required time period" (Meister, 1966). This definition does not contain any references to why the error occurred, but instead focuses on the consequences of the error for the system (loss or unavailability of a required function). The disadvantage of such a definition is that it fails to consider the wide range of other actions that the human might make, which may have other safety implications for the system, as well as not achieving the required function. [Pg.39]

In the case of a latent human error the consequences of the error may only become apparent after a period of time when the condition caused by the error combines with other errors or particular operational conditions. Two types of latent error can be distinguished. One category originates at the operational level and leads to some required system function being degraded or unavailable. Maintenance and inspection operations are a frequent source of this type of latent failure. [Pg.40]

They provide useful data for evaluating the worker s understanding of how the system functions. [Pg.177]

Price, H. E. (1985). The Allocation of System Functions. Human Factors 27,33-45. [Pg.374]

Human Error Probability The probability that an error will occur during the performance of a particular job or task within a defined time period. Alternative definition The probability that the human operator will fail to provide the required system function within the required time. [Pg.412]

Formal systems have well-documented descriptions of how the system functions and records exist that demonstrate the systems are working. [Pg.38]

X 10 M), and an equivalent amount of OH (its usual concentration in plasma) would swamp the buffer system, causing a dangerous rise in the plasma pH. How, then, can this bicarbonate system function effectively The bicarbonate buffer system works well because the critical concentration of H2CO3 is maintained relatively constant through equilibrium with dissolved CO2 produced in the tissues and available as a gaseous CO2 reservoir in the lungs. ... [Pg.52]

Unlike other infrared techniques, thermal or infrared imaging provides the means to scan the infrared emissions of complete machines, process or equipment in a very short time. Most of the imaging systems function much like a video camera. The user can view the thermal... [Pg.799]

High concentrations of KOP have been found in the cerebral cortex and hypothalamus KOP is also present in the gastrointestinal tract, in immune cells as well as in other peripheral tissues. KOPs have been implicated in the regulation of nociception, diuresis, feeding, neuroendocrine and immune system functions [2]. [Pg.905]

Pituitary Adenylyl Cyclase-activating Polypeptide (PACAP) is a 38-amino acid peptide (PACAP-38), which is widely expressed in the central nervous system. PACAP is most abundant in the hypothalamus. It is also found in the gastrointestinal tract, the adrenal gland and in testis. Its central nervous system functions are ill-defined. In the periphery, PACAP has been shown to stimulate catecholamine secretion from the adrenal medulla and to regulate secretion from the pancreas. Three G-protein coupled receptors have been shown to respond to PACAP, PAQ (PACAP type I) specifically binds PACAP, VPACi and VPAC2 also bind vasoactive intestinal peptide (VDP). Activation of PACAP receptors results in a Gs-mediated activation of adenylyl cyclase. [Pg.979]

Grace AA (2001) Psychostimulant actions on dopamine and limbic system function relevance to the pathophysiology and treatment of ADHD. In Solanto MV, Arnsten AFT, Castellanos FX (eds) Stimulant drugs and ADHD, Oxford University Press, pp 134—157... [Pg.1043]

The Fourier transform H(f) of the impulse response h(t) is called the system function. The system function relates the Fourier transforms of the input and output time functions by means of the extremely simple Eq. (3-298), which states that the action of the filter is to modify that part of the input consisting of a complex exponential at frequency / by multiplying its amplitude (magnitude) by i7(/)j and adding arg [ (/)] to its phase angle (argument). [Pg.181]

This equation assumes a much simpler form if we express it in terms of the system function H(f) instead of the impulse response h(t) namely, as reference to Eq. (3-300) shows... [Pg.182]

In other words, the output power is the area under the product of the Fourier transform of Rx(r) and the squared modulus of the system function H(f). [Pg.183]

Symmetry used in determining magnetic structure, 758 Synchronization, 372,373 theory by stroscopic method, 375 System function, 181 Systems... [Pg.784]


See other pages where System functions is mentioned: [Pg.126]    [Pg.135]    [Pg.116]    [Pg.112]    [Pg.107]    [Pg.106]    [Pg.147]    [Pg.209]    [Pg.214]    [Pg.311]    [Pg.1359]    [Pg.135]    [Pg.606]    [Pg.19]    [Pg.164]    [Pg.164]    [Pg.908]    [Pg.1188]    [Pg.188]    [Pg.121]   
See also in sourсe #XX -- [ Pg.311 , Pg.317 , Pg.419 , Pg.423 , Pg.424 , Pg.425 , Pg.601 ]

See also in sourсe #XX -- [ Pg.405 ]




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