Uncontrolled responses

A controlled response is defined as a response capable of being set to a specified level by the experimenter an uncontrolled response is a response not capable of being set to a specified level by the experimenter. 

Figure 8.4 Uncontrolled response to changes depicted in figure 8.3 — note that the thermal capacity damps down the fluctuations...

The test program includes three major steps (1) Bare building test to identify the d5mamic parameters of the building at the time and to establish the uncontrolled response for future comparisons (2) MTMD design and fabrication to create the control device based on the identified... 

Emergency procedures Uncontrolled responses Chaotic evacuation... 

This provides the best estimate of the expected standard deviation for results obtained by several laboratories, due to the effects of small changes in uncontrolled or poorly controlled factors. If this standard deviation is unacceptably large, then the procedure may be modified to bring under greater control those factors whose levels have the greatest effect on the response. 

For the chlor-alkali industry, an emergency preparedness and response plan is mandatory for potential uncontrolled chlorine and other releases. Carbon tetrachloride is sometimes used to scrub nitrogen trichloride (formed in the process) and to maintain its levels below 4% to avoid fire and explosion. Substitutes for carbon tetrachloride may have to be used, as the use of carbon tetrachloride may be banned in the near future due to its carcinogenicity. 

Porous samples would appear on the surface to provide such a complex and uncontrolled local environment for deformation of solids that they would be of little interest in scientific investigations. Indeed, the principal interest in their responses is technologically driven they are very effective attenuators of wave profiles and much of materials synthesis and processing is carried out on powders. Duvall [86D01] has summarized the difficulty of work with porous powder samples as follows ... 

OSHA s Hazardous Waste Operations and Emergency Response (HAZWOPER) legislation protects workers who respond to emergencies, such as serious spills, involving hazardous materials. It also covers those employed in cleanup operations at uncontrolled hazardous waste sites and at EPA-licensed waste treatment, storage, and disposal facilities. 

In rare cases of a systemic release, kinins have the potential to cause severe hypotension. Uncontrolled activation of the contact system (Fig. 3) is thought to trigger a massive formation of kinins under certain pathological conditions [3]. For instance, this situation is seen in patients with underlying diseases such as systemic inflammatory response syndrome (SIRS) due to sepsis or trauma. SIRS progression is accompanied by depletion of contact system factors and low levels of H-kininogen and plasma kallikrein are indicative of a... 

Oevere toxicological responses have been associated with certain chloro- dibenzodioxins. One of these responses is chloracne, a folliculosis first associated with skin contamination by chlorohydrocarbons in 1899 (3). Serious outbreaks of chloracne-like lesions associated with runaway reactions in the production of 2,4,5-trichlorophenol occurred in Germany in the early 1950 s (5). 2,4,5-Trichlorophenol itself does not cause acne (S), but the contaminants which may be formed in the uncontrolled production of 2,4,5-trichlorophenol are extremely potent acnegens (5). 2,3,7,8-Tetrachlorodibenzo-p-dioxin and tri- and tetra-... 

This model was developed after pioneering experiments carried out in the USA by Overmier and Seligman (1967) who reported profound behavioural changes in dogs after their exposure to inescapable, uncontrollable stress (footshock). Subsequent work has concentrated on rats and mice, which show a similar behavioural response. This is expressed as appetite and sleep disturbance, general passivity and, on re-exposure of subjects to the stress, a failure to attempt to escape ( escape deficits ), even when this is feasible. 

Cohen and Coon observed that the response of most uncontrolled (controller disconnected) processes to a step change in the manipulated variable is a sigmoidally shaped curve. This can be modelled approximately by a first-order system with time lag Tl, as given by the intersection of the tangent through the inflection point with the time axis (Fig. 2.34). The theoretical values of the controller settings obtained by the analysis of this system are summarised in Table 2.2. The model parameters for a step change A to be used with this table are calculated as follows... 

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