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Defined operational boundary

A situation where we are able to keep the operation within defined operating boundaries and at a particularly desired level where the need of operational control is limited. [Pg.97]

A situation where operational conditions are particularly challenging due to bad weather, a challenging well with unstable formation pressure etc. But despite these challenges the operation is performed within defined operation boundaries by means of normal control functions. [Pg.97]

A situation where normal control was lost, and the process escaped the defined operating boundaries in the first place, but controlled was gained... [Pg.97]

It is important, especially when consistency has not been designed or built into the maintenance reporting system, to review the data reported to minimize misinterpretation. Clearly defined equipment boundaries for plant hardware are essential for the generation of relevant data. For example, one classification method may define pumps as only the mechanical portions of the pump, whereas another may include the driver (e.g., the motor) and associated controls. Interviews with operating and maintenance personnel as well as review of the maintenance procedures and documents can provide insight into the... [Pg.216]

PrImary-Voltage-Control-AC Motor Driver. Induction motor torque at any slip s is proportional to primary V. Rotor-power dissipation is equal to s times the air-gap power. These two relationships define the boundary of operation of an induction motor with primary voltage control of speed. As the speed is reduced (s increased) at constant torque, the air-gap power remains fixed, but the power divides between rotor circuit dissipation and mechanical shaft power. [Pg.418]

The size assigned to an atom or ion requires a decision about where an atom stops. From quantum mechanics we learn that an atom has no sharp boundaries or surfaces. Nevertheless, chemists find it convenient to assign sizes to atoms according to the observed distances between atoms. Thus, atomic size is defined operationally—it is determined by measuring the distance between atoms. [Pg.354]

This mapping from to the classes C, is determined by the discriminant functions that define the boundaries of regions I = 1,2,...,K in 5. Let d, p) be the discriminant function associated with the 7th class of operating situations, where /= 1,2,..., K. Then, a pattern of measurements p, implies the operating situation C, iff... [Pg.257]

No single method is perfect and common problems include the difficulty of defining peak boundaries accurately, operator dependence on precision and the need for a finite time to make each measurement. A major disadvantage of manual measurements is the necessity that all peaks of Interest must be completely contained on the chart paper (or adjusted to remain on the chart paper by varying the detector attenuation during the... [Pg.49]

In accordance with this definition, an environmental risk assessment process is used especially in cases when the probability component arises during the calculation of various parameters which can be due to many reasons uncertainty of input information uncertainties in applying an algorithm due to lack of knowledge, insufficient knowledge and/or simplification of input information uncertainties in the defined geographic boundaries of pollutant influence uncertainties in both computer calculations and management operations based on these calculations. [Pg.75]

Define the boundaries and its operational mode(s) of the facility under review. [Pg.36]

To find the matrix S, we must define suitable boundary conditions. It is expedient to consider a hypothetical chain with 2N bonds, instead of N, supposing it to be a portion of an infinite superchain repeating identically after each stretch of 2N bonds. Assuming [Pg.273]

As discussed above, SVOCs are removed from the atmosphere and transported to the waters by precipitation scavenging of atmospheric vapors and particles, which are incorporated into the rain within or below the clouds. After SVOCs are deposited into the bulk seawater, partitioning in water column can affect the distribution of pollutants between the dissolved aqueous and the solid phases and eventually impact the fate of these compounds in oceans (Luo et al. 2004). In addition, air-sea exchange can make SVOCs diffuse across the air-sea interface however, the sea surface microlayer (SML), a unique compartment at the air-sea boundary defined operationally as the upper millimeter (1-1,000 pm)... [Pg.296]

Equation 1 is the continuum equilibrium condition, Eq. 2 are the constitutive equations, which specify the material behavior, and Eq. 3 are the kinematics, the displacement-deformation conditions. The forming machine defines the boundary conditions for this set of partial differential equations. It can be seen without going into details that those equations are essentially grade two in the displacements, which means that boundary conditions are in the displacements or in the first derivative of displacements. Eirst derivatives of displacements are in all constitutive equations connected to stress at least due to elasticity, which is common for all materials. Erom these two types of press machines can be derived, namely, path-driven machines, where boundary conditions for the displacements are prescribed, and force-driven machines, where stress boundary conditions are prescribed, which are integrated to the press force. Erom this it follows also that despite the possibilities of servo presses to operate under different modes of the drive, path, force, or energy, nothing really new is added, because the drive can only introduce either boundary condition at a time. [Pg.548]

In view of the aforementioned remarks and, despite the important information supplied by the material that has been detailed here, the subject of characterization of interacting sprays remains a formidable challenge. It would appear that a solid database of experimental measurements made under a comprehensive set of well-defined operating conditions is very much needed. This database will serve a dual purpose. On the one hand, it will help to gain a deeper understanding of the relative importance of the physical mechanisms at play as a result of the interaction. On the other hand, it will serve as a source of initial/boundary conditions for theoretical and computer simulations and will be an excellent reference for validating such simulations. [Pg.474]

Our team charter had defined our boundaries, so we started with a flat sheet metal part that has already been stamped from coil stock at a preceding operation. The team s first stop was a machine that bent up all four edges of the blank sheet metal to form a pan. What the team observed was that the parts were brought to this machine in a container that required the operator to bend over to retrieve the vertically stacked parts. The operator also had to pry apart the sheet metal pieces with his fingertips before he lifted them from the container. The oil that had accumulated on the parts from the previous stamping operation caused the parts to stick together. The... [Pg.84]

Operational modes are used to categorize the requirements placed on the facility as a convenience for management control. Furthermore, modes are used in the TSRs to clearly define operational condition boundaries and as a means of establishing facility status. They define equipment operability requirements and allowable actions by operations personnel under normal, abnormal, and accident conditions. More specifically, modes are used to define the applicability of the actions or conditions specified by the TSR limits. [Pg.219]

In the case of the feasibility analysis stage (Space 2 in section 4.5) the required input information involves the process basis of design. In other words, feedstock and product purities and operational boundaries should be defined. Additionally, sustainability and... [Pg.90]


See other pages where Defined operational boundary is mentioned: [Pg.106]    [Pg.96]    [Pg.96]    [Pg.96]    [Pg.106]    [Pg.96]    [Pg.96]    [Pg.96]    [Pg.13]    [Pg.4]    [Pg.8]    [Pg.593]    [Pg.196]    [Pg.161]    [Pg.237]    [Pg.8]    [Pg.122]    [Pg.337]    [Pg.722]    [Pg.708]    [Pg.925]    [Pg.344]    [Pg.95]    [Pg.185]    [Pg.254]    [Pg.138]    [Pg.207]    [Pg.221]    [Pg.200]    [Pg.159]    [Pg.71]    [Pg.59]    [Pg.185]    [Pg.292]   


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Boundary, defined

Operationally-defined

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