Elimination objective

The problems of inadequate training and test set selections have already been discussed in detail in Section 3. The same problem is also observed in cross-validation. In well-designed training sets, where a small number of objects is selected to explore the parameter space with a minimum number of experiments, cross-validation fails the eliminated objects cannot be predicted by models which are derived from objects that do not contain all structural features of the excluded objects. 

Another method of eliminating collision checks was proposed but not implemented in this initial collision prediction system elimination by the dynamic position of objects in the environment. Some objects can move in and out of range of other objects. For example, a space manipulator on a moving platform may move from one position on the Space Station, where it must avoid certain antennae, to another position where the antennae are out of reach, but the solar arrays are now a concern. In dynamic collision elimination, objects in the antennae cluster would be removed from the collision-check list of the manipulator, while the solar array objects would be added. Using this approach, major sections of the geometric database could be removed from consideration, greatly reducing the required calculations at each cycle. 

The dimensionality of a data set is the number of variables that are used to describe eac object. For example, a conformation of a cyclohexane ring might be described in terms c the six torsion angles in the ring. However, it is often found that there are significai correlations between these variables. Under such circumstances, a cluster analysis is ofte facilitated by reducing the dimensionality of a data set to eliminate these correlation Principal components analysis (PCA) is a commonly used method for reducing the dimensior ality of a data set. 

Failure Mode and Effects Analysis. The system design activity usually emphasizes the attainment of performance objectives in a timely and cost-efficient fashion. The failure mode and effects analysis (FMEA) procedure considers the system from a failure point of view to determine how the product might fail. The terms design failure mode and effects analysis (DFMEA) and failure mode effects and criticaUty analysis (EMECA) also are used. This EMEA technique is used to identify and eliminate potential failure modes early in the design cycle, and its success is well documented (3,4). 

The most effective specification is that which accomplishes the desired result with the fewest requirements. Properties and performance should be emphasized rather than how the objectives ate to be achieved. Excessive demonstration of emdition on the part of the writer or failure to recognize the usually considerable processing expertise held by the vendor results in a lengthy and overly detailed document that generally is counterproductive. Redundancy may lead to technical inconsistency. A requirement that cannot be assessed by a prescribed test method or quantitative inspection technique never should be included in the specifications. Wherever possible, tests should be easy to perform and highly correctable with service performance. Tests that indicate service life are especially useful. Standard test references, eg, ASTM methods, ate the most desirable, and those that ate needed should be selected carefully and the numbers of such references should be minimized. To eliminate unnecessary review activity by the would-be complier, the description of a standard test should not be paraphrased or condensed unless the original test is referenced. 

The main objectives of RCRA ate to protect pubHc health and the environment and to conserve natural resources. The act requires EPA to develop and adininistet the following programs soHd waste disposal practices providing acceptable protection levels for pubHc health and the environment transportation, storage, treatment, and disposal of hazardous wastes practices that eliminate or minimize hazards to human health and the environment the use of resource conservation and recovery whenever technically and economically feasible and federal, state, and local programs to achieve these objectives. 

The principal objectives of pretreatment are to remove heavy metals prior to subsequent treatment, to neutralize the wastewater to a suitable pH for discharge or subsequent treatment to remove high concentrations of suspended soflds, to eliminate or reduce toxicity, and to eliminate or reduce volatiles. The concentrations of various pollutants that make pretreatment desirable are summarized in Table 7. 

There have been a number of cell designs tested for this reaction. Undivided cells using sodium bromide electrolyte have been tried (see, for example. Ref. 29). These have had electrode shapes for in-ceU propylene absorption into the electrolyte. The chief advantages of the electrochemical route to propylene oxide are elimination of the need for chlorine and lime, as well as avoidance of calcium chloride disposal (see Calcium compounds, calcium CHLORIDE Lime and limestone). An indirect electrochemical approach meeting these same objectives employs the chlorine produced at the anode of a membrane cell for preparing the propylene chlorohydrin external to the electrolysis system. The caustic made at the cathode is used to convert the chlorohydrin to propylene oxide, reforming a NaCl solution which is recycled. Attractive economics are claimed for this combined chlor-alkali electrolysis and propylene oxide manufacture (135). 

Lead and Lead-Lined Steel Pipe Lead and lead-hned steel lipe have been essentially eliminated as piping materials owing to lealth hazards in fabrication and installation and to environmental objections. Lead has been replaced by suitable plastic, reinforced plastic, plastic-lined steel, or high-alloy materials. 

Different manufacturers have adopted different methods with minor changes to achieve almost the same objective. For example, field-oriented control was first introduced by Allen Bradley in the USA in 1981 and a similar technique was introduced at the same time by ABB of Finland. ABB claim their technique to be still faster in responding, as it eliminates the modulation section of... 

This brings us to what the real objectives behind P2 are about. Pollution prevention is a carefully plarmed investment aimed at reducing an enterprise s operating costs through the elimination of harmful pollution. A successful P2 activity is a win-win type of investment — that is, the company not only eliminates pollution at the source, but does so on the condition that, at the very least, the activity pays for itself and, more favorably, provides attractive financial returns. The re-engineering considered for the pollution reduction and/or elimination must meet a set of well-defined financial goals within the enterprise otherwise it is not a worthwhile P2 practice. 

A primary objective of any safety program is to maintain or reduce the level of risk in the process. The design basis, especially inherently safer features that are built into the installation, must be documented. Management of change programs must preserve and keep the base record current and protect against elimination of inherently safer features. For identical substitution, the level of risk in the process is... 

Reducing and eliminating hazards and their associated risks is the second major objective. Applying inherent safety principles early in the product/process development effort provides the greatest opportunity to achieve the objectives of the inherent safety review process for the project at hand. If these principles are applied late in the effort the results may have to be applied to the project after next as the schedule may not permit implementation of the results. 

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