Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Continuous time function

The terms Pmax and Pmax denote the limiting capacities of the inspiratory muscles, and n is an efficiency index. The optimal Pmus(t) output is found by minimization of / subjects to the constraints set by the chemical and mechanical plants. Equation 11.1 and Equation 11.9. Because Pmusif) is generally a continuous time function with sharp phase transitions, this amounts to solving a difficult dynamic nonlinear optimal control problem with piecewise smooth trajectories. An alternative approach adopted by Poon and coworkers [1992] is to model Pmus t) as a biphasic function... [Pg.184]

Assure that the interlock (hardware, software, and I/O) continues to function as designed. The design must also determine the time interval on which this must be done. Often these tests must be done with the plant in full operation. [Pg.798]

It is important to keep in mind that any evaluation will reflect a snapshot in time, showing whether systems are in place and have been or are functioning. It is only by including appropriate characteristics of good management systems in the assessment that there can be assurance that these programs will continue to function effectively in the future. [Pg.88]

Continuous Memoryless Channels.—The coding theorem of the last section will be extended here to the following three types of channel models channels with discrete input and continuous output channels with continuous input and continuous output and channels with band limited time functions for input and output. Although these models are still somewhat crude approximations to most physical communication channels, they still provide considerable insight into the effects of the noise and the relative merits of various transmission and detection schemes. [Pg.239]

Equation (4-210) is known as the sampling theorem. It states that any time function limited to a frequency W can be uniquely determined by its values at sample points spaced 1/2W apart. Thus if both the input and output from a channel are limited to a frequency W, then we can represent the input and output as sequences of real numbers spaced at intervals of 1/2 W. If each output in this sequence depends on only one input, then the results for continuous input, continuous output channels can be applied. One particularly important case in which ... [Pg.245]

The amount accepted for stocking is the minimum of R and the quantity to satisfy back-logged demand bringing the level up to 8. The demand in the i 1 period is given by a random variable , with continuous density function ( ) , all variables ,(t = 1,2, ) are independently and identically distributed. The level of stock at the end of period i is represented by the random variable Xt measured before adding any delivery occurring at time i. Let the random variable be the time of the t1 delivery. Then Prob (17, = 0) = 1. We can write X t and Rm to indicate dependence on ij. We have ... [Pg.282]

We can conclude that the continuous-time STN and RTN models based on the definition of global time points are quite general. They are capable of easily accommodating a variety of objective functions such as profit maximization or makespan minimization. However, events taking place during the time horizon such as multiple due dates and raw material receptions are more complex to implement given that the exact position of the time points is unknown. [Pg.175]

There are two sources of biochemicals in soil one is the cellular constituents released when cells are destroyed during the extraction process. It should be kept in mind that any handling of a soil sample will cause the destruction of some of the cells it contains. The simple act of sieving, air drying, and weighing soil will cause some lyses of cells and release of their contents. Extraction will typically cause complete destruction of all cells in soil, with the release of all their constituent parts. Some parts such as enzymes may continue to function after release from the cell and continue to change the makeup of soil components for some time. [Pg.96]

The signal emerging from the detector of a HPLC is recorded continuously as function of time most commonly with the help of a potentiometric recorder. Invariably, a recorder of 1 to 10 mV full-scale deflec-... [Pg.465]

These results indicate that our scaled-up model ecosystems are more useful for studying system processes than processes that function in individual components of the environment. In this regard, a preliminary large scale ecosystem study could be very useful to indicate parameter limits such as overall degradation rates and likely concentrations of parent compounds plus metabolites over time. Such information would be useful in the design of metabolic studies in various components of the ecosystem. In addition, the large scale ecosystem study could also be used to determine if processes derived under laboratory conditions continue to function and/or predominate when combined in a complex system. [Pg.215]

To account for the effect of a sufficiently broad, statistical distribution of heterogeneities on the overall transport, we can consider a probabilistic approach that will generate a probability density function in space (5) and time (t), /(i, t), describing key features of the transport. The effects of multiscale heterogeneities on contaminant transport patterns are significant, and consideration only of the mean transport behavior, such as the spatial moments of the concentration distribution, is not sufficient. The continuous time random walk (CTRW) approach is a physically based method that has been advanced recently as an effective means to quantify contaminant transport. The interested reader is referred to a detailed review of this approach (Berkowitz et al. 2006). [Pg.226]

Pharmacokinetics When administered intravenously, ICG rapidly binds to plasma proteins and is exclusively cleared by the liver, and subsequently secreted into the bile [8]. This forms the basis of the use of ICG for monitoring hepatic blood flow and function. Two pharmacokinetics models, a monoexponential decay, which describes the initial rapid clearance of ICG with a half-life of about 3 minutes (Eq. (1)) and a bi-exponential model, which incorporates the secondary phase clearance with a longer half-life (Eq. (2)), describe total clearance of ICG from plasma [ 132]. For real-time measurements by continuous organ function monitoring, the mono-exponential decay is preferred. [Pg.46]

While still preliminary, this study demonstrates the feasibility of evaluating the renal status in real-time by optical modality. This continuous renal function monitoring by the optical modality represents a new and minimally invasive method to detect kidney malfunctions. In addition to using relatively harmless radiation, the simplicity and portability of the equipment make this approach compatible for use in ambulatory and critical care. However, further studies... [Pg.63]

All of the areas of proof described above provide evidence concerning the current operations of the computer systems in place, but can those same controls be expected to continue to function over time Certainly a trend of control provides some presumption, and annual SOP review procedures provide a degree of assurance, but the most significant evidence of system reliability lies internal to the software and is documented only through a review of that source code itself. [Pg.183]

Therefore the authors introduced the concept of holistic validation where the whole chromatographic system was also qualified to evaluate the performance of the system. The concept of holistic qualification is important as some laboratories operate with a policy of modular equipment purchase. Here they select components with the best or optimum performance from any manufacturer. Furthermore, some of these laboratories may swap components when they malfunction. Thus, over time the composition of a system may change. Therefore, to assure themselves and any regulatory bodies that the system continues to function correctly, holistic qualification is vital. [Pg.23]

In the Eulerian view, a fluid is characterized by fields of intensive variables or properties r). For example, the internal energy (or temperature, for a constant specific heat) is assumed to be a continuous function of time and space, r)(t,x). Because rj is a continuous differentiable function, the following expansion is generally valid ... [Pg.23]

These increasing and decreasing concentration trends do not appear to be a function of the spectrometric method. Continuous time vs. relative intensity curves were prepared for the iron internal standard... [Pg.49]

One of the simplest methods to generalize formal kinetics is to treat reactant concentrations as continuous stochastic functions of time, which results in a transformation of deterministic equations (2.1.1), (2.1.40) into stochastic differential equations. In a system with completely mixed particles the macroscopic concentration n (t) turns out to be the average of the stochastic function Cj(<)... [Pg.84]

Here, we present an approach for the description of such anomalous transport processes that is based on the continuous-time random walk theory for a power-law waiting time distribution w(t) but which can be used to find the probability density function of the random walker in the presence of an external force field, or in phase space. This framework is fractional dynamics, and we show how the traditional kinetic equations can be generalized and solved within this approach. [Pg.227]


See other pages where Continuous time function is mentioned: [Pg.142]    [Pg.85]    [Pg.86]    [Pg.327]    [Pg.322]    [Pg.142]    [Pg.85]    [Pg.86]    [Pg.327]    [Pg.322]    [Pg.1486]    [Pg.167]    [Pg.214]    [Pg.65]    [Pg.498]    [Pg.441]    [Pg.92]    [Pg.42]    [Pg.167]    [Pg.181]    [Pg.203]    [Pg.454]    [Pg.33]    [Pg.62]    [Pg.63]    [Pg.518]    [Pg.83]    [Pg.134]    [Pg.215]    [Pg.137]    [Pg.174]   
See also in sourсe #XX -- [ Pg.85 ]




SEARCH



Continuous function

Continuous time

Function continuity

Functional continuous

Functioning time

Time function

Timing function

© 2024 chempedia.info