Operating specifications

Good measurement practices (GMPs) describe operations specific to a technique. In general, GMPs provide instructions for maintaining, calibrating, and using the equipment and instrumentation that form the basis for a specific technique. For example, a GMP for a titration describes how to calibrate a buret (if nec-... 

The use of the computer in the design of chemical processes requires a framework for depiction and computation completely different from that of traditional CAD/CAM appHcations. Eor this reason, most practitioners use computer-aided process design to designate those approaches that are used to model the performance of individual unit operations, to compute heat and material balances, and to perform thermodynamic and transport analyses. Typical process simulators have, at their core, techniques for the management of massive arrays of data, computational engines to solve sparse matrices, and unit-operation-specific computational subroutines. 

The review should emphasize developing an understanding of the processing sequence, the equipment, the equipment plot, the operating conditions, instrument and sample locations, the control decisions, and the operators perspectives. Wmle the preparation effort may be less for those who have been responsible for the unit for a long period of time, the purpose of the test requires that the types and locations of the measurements be different from those typically recorded and typically used. The condition of these locations must be inspected. Operating specifications may be different. Therefore, refreshment is always necessaiy... 

Focus For the purposes of this discussion, a model is a mathematical representation of the unit. The purpose of the model is to tie operating specifications and unit input to the products. A model can be used for troubleshooting, fault detection, control, and design. Development and refinement of the unit model is one of the principal results of analysis of plant performance. There are two broad model classifications. 

Parameter Estimation Relational and physical models require adjustable parameters to match the predicted output (e.g., distillate composition, tower profiles, and reactor conversions) to the operating specifications (e.g., distillation material and energy balance) and the unit input, feed compositions, conditions, and flows. The physical-model adjustable parameters bear a loose tie to theory with the limitations discussed in previous sections. The relational models have no tie to theory or the internal equipment processes. The purpose of this interpretation procedure is to develop estimates for these parameters. It is these parameters hnked with the model that provide a mathematical representation of the unit that can be used in fault detection, control, and design. 

The best test for the suitability of the models is to develop their respec tive parameter estimates at one set of conditions and then test the accuracy of the models using measurements for other sets of conditions. The other conditions can be as relatively close to those used to establish the parameter estimates as might be experienced in routine operations. They may also be far different with different feed conditions and operating specifications. 

This guideline describes methods to help the chemical processing industry apply the CCPS chemical process safety concepts to outsourced manufacturing operations, specifically the tolling vendor-client relationship. In addition to the focus on process safety, information and examples provided in this text foster good practices relative to community and worker health, and environmental responsibility. 

The immune system in vertebrates provides a defense mechanism against foreign parasites such as viruses and bacteria. Three main properties are essential to its successful operation specific recognition of foreign molecules, the ability to destroy the foreign parasite, and a memory mechanism that allows a more rapid response to a second infection by the same microorganism. 

The apparatus employed for any given analysis will have operating specifications that are unique to the particular instrument that is selected or that is available. These specifications have been determined by the design and method of manufacture of the instrument and can differ significantly from one chromatograph to another. Some will control and limit the ultimate performance achieved by any column with which the instrument is used. However, it is likely that, as a result of careful design by the manufacturer, the important instrument characteristics affecting column... 

Non-RCRA-permitted TSDs and waste treatment activities not covered by RCRA (e.g., wastewater treatment facilities permitted under the Clean Water Act) are not covered by HAZWOPER, except for emergency response and some limited waste management operations. Specific HAZWOPER elements are assimilated into the existing health and safety program based on hazard analyses. Worker protection requirements are met through existing health and safety plans [1]. 

The contractor s SSAHP for Site C contained task- and operation-specific hazard analyses and safety and health procedures that covered general operations, but they were not specific enough for prescribing control methods and PPE for each job task. The plan identified some safety hazards for each operation but did not describe SOPs for protecting employees from these hazards. The SSAHP did, however, contain personnel and equipment decontamination procedures used at the site. 

A typical operating specific speed curve is shown in Figure 3-50 and represents a technique for plotting the specific speed on the operating performance curve. Figure 3-50 represents a 6-inch pump operating at 1760 rpm, with maximum efficiency at 1480 GPM and 132 feet head [25]. The operating specific speed is zero at no flow and increases to infinity at the maximum flow of 2270 gpm and zero head. Stable operations beyond about 1600-1700 gpm cannot be planned from such a curve with a sharp cutoff drop for head capacity. 

Type specific speed is defined as that operating specific speed that gives the maximum efficiency for a specific pump and is the number that identifies the pump type [25]. This index number is independent of the rotative speed at which the pump is operating, because any change in speed creates a change in capacity in direct proportion and a change in head that varies as the square of the speed [25]. Practice is to true type the specific speed of the pump reasonably close to the conditions of maximum effi-... 

The lubricants generally specified for conventional gas turbines invariably fall within the same classification as those used for steam turbines and are often categorized as turbine oils . In those cases where an aircraft type gas turbine has been adapted for industrial use the lubricant is vitally important to their correct operation. Specifications have been rigidly laid down after the most exhaustive tests, and it would be unwise, even foolhardy, to depart from the manufacturers recommendations. No economic gain would result from the use of cheaper, but less efficient, lubricants. 

Because of this, all new machinery should be thoroughly inspected for defects before installation. Acceptance criteria should include guidelines that clearly define acceptable design/operational specifications. This practice pays big dividends by increasing productivity and decreasing unscheduled downtime. 

In a GLP-compliant laboratory, a data system must meet explicit requirements guaranteeing the validity, quality, and security of the collected data. Operational qualification (OQ) must be performed after any new devices are installed in the laboratory system and whenever service or repair are performed. The role of OQ is to demonstrate that the instrument functions according to the operational specifications in its current laboratory environment. If environmental conditions are highly variable, OQ should be checked at the extremes in addition to normal ambient conditions. Performance qualification (PQ) must be performed following any new installation and whenever the configuration of the system has been changed. PQ demonstrates that the instrument performs according to the specifications appropriate for its routine use. 

Determine the range of satisfactory performance and the resultant yields for various reactor lengths for the following operating specifications. 

Operational qualification Auditing/testing process that evaluates the system being tested to make sure that it is fully operational and will perform within operating specifications... 

Chapter 2, Static Models Object Attributes and Invariants, describes how attributes abstract variations in the implementation of object state. Chapter 3, Behavior Models Object Types and Operations, describes how operation specifications describe externally visible behavior of an object, independently of algorithmic and representation decisions. 

The combination of all invariants for a class can be used in a single ok() function, which should evaluate to true after any external invocation of an operation on the object. Such a function provides a valuable sanity check on the state of a running applicatioa Together with operation specifications, it provides the basis for both testing and debugging. 

Even if invariants and operation specifications will not be formalized, you can concisely define the terminology of types and attributes and consequently of operation requirements. Contrast the following updated informal operation specifications with the ones we started with. (Which is worse reams of ambiguous narrative, or tomes of formal or pseudoformal syntax with no explanatory prose )... 

Operation specifications can be simplified by taking advantage of constraints in the type model. Consider the type model of Scheduler in Figure 3.13 with these invariants ... 

The unnecessary parts would not be incorrect, only redundant. Removing them leaves a much simpler operation specification ... 

We have seen how certain elements of an operation specification are implied by the invariants. Writing them would not be incorrect, only redundant. It can still be useful to write them down note the change dates example earlier. However, it is worth distinguishing those parts of the specification the designer should explicitly pay attention to—the invariants and necessary parts of operation specs—from those parts that would automatically be satisfied as a result. 

A good operation specification is much like a test specification. With a little infrastructure support—such as query functions to map from concrete data representations to the abstract attributes used in the specifications and some means to capture initial values of attributes—these operation specifications can be mapped to test code that is executable at runtime, at least during testing or debugging. 

Each individual state chart effectively specifies how every action on the primary type affects that one specification type. In contrast, a complete action specification defines how one action on the primary type affects any specification type member. The composition of all change dates transitions, on ary and all specification types, constitutes change dates operation specification for the scheduler. Do not confuse this state chart view with internal design, when we will actually decide internal interactions between objects within the scheduler, the primary types whose behavior we describe will be these internal objects. 

We have seen how an entire sequence of interactions between objects can be abstracted and described as a single joint action. We will next see how even in program code, an operation invocation itself has two sides the sender and the receiver. By using input and output parameters, a localized operation specification decouples the effect on the receiver from any information about the initiator. 

We describe an object s behavior using a type, with two parts to its specification the operation specifications (usually pre- and postconditions) defining what it does and the static model, providing the vocabulary of terms for the operation specs. 

Write the new operation specification using the anded expressions as... 

The primary deliverable is a type specification the system being developed specified as a type, with a type model (attributes and associations) and a set of operations specified against that type model. Defining the type involves identifying each action in which the system participates and specifying it as an operation on the type. The behavior can be described with state charts in addition to operation specifications and can be exercised with scenarios and snapshots. 

Informal Specs. The formal behavior specifications start with informal narrative, and end with much clearer narrative description (see Section 3.4.1, From Attributes to Operation Specification, on page 129). Always review this narrative specification, and the definitions in the Dictionary. Explain to the customer that the terms reflect the system s view of the domain, not necessarily every aspect of the domain itself. 

The former is always centered around type models and operation specifications, and should very rarely discuss classes and inheritance. The latter is focused on collaborations between objects, and includes the corresponding type models of each one it can include many more details of code structure and re-use e.g. class inheritance. 

UML treats attributes on a type as abstract but does not permit attributes to take parameters instead, you can use an operation that has been marked as read-only. Catalysis encourages a slightly different way of thinking about an object Some things are abstractions of its state, and others are abstractions of its behaviors. Attributes, parameterized attributes, and invariants all help to define the model of state operation specifications define the behaviors. There are no preconditions and postconditions on attributes, because they represent state there can be conditional invariants on an attribute, and there can be syntactic shortcuts for expressing them, but they are not pre- and postconditions ... 

If all responses to these tests are linear and typical, and all other independent variables remain within normal operating specifications, it can be assumed that the membrane and electrolyser interactions are optimised for operation within the current density range tested in Section 6.3.1. This procedure has been used successfully to diagnose and optimise operating conditions for both standard and high current density operations where unexpected performance issues have arisen. Furthermore, operators... 

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