Idle time

The direct-labor-cost variance can, if necessary, be broken down into a direc t-labor-idle-time variance in addition to the direct-wage-rate and direct-labor-efficiency variances. The direc t-labor-idle-time variance is simply the number of idle labor-hours in the period multiplied by the standard wage rate. This is rarely relevant to the conditions existing in process plants except when maintenance is involved. 

Hourly Rate This intermediate rate takes into account equipment stoppages due principally to mechanical downtime rather than the equipment s idle time bile it waits for ac tion by other parts of the system. 

Failures of this type occurred every 6 to 9 years. The well was operated intermittently, since several available wells are operated on a rotating basis. It is probable that most of the graphitic corrosion occurred during idle times actual metal loss occurred during operation of the pump. 

By the very nature of batch processing, it is inevitable that process equipment will have idle time between batches. The idle time also could occur if the controller is not being used at all times during the execution of the batch (e.g., a flow controller may only be used during the feed of one of the reactants). During the idle time, control considerations such as reset windup must be considered to prevent the control signal from going outside of the control limits. 

Nutsche filters are usually operated as part of a batch system, and hence the vessel s volume is designed to accept an entire charge of slurry from the upstream equipment. Therefore, so that the idle time of the filter is kept to a minimum. 

These diagrams focus on the temporal or time relationships of operations and they can be used to solve resource allocation problems, to determine whether there is any potential for time stress, and to consider alternative work methods in the execution of a procedure. An example drawn from traditional industrial engineering methods is shown in Figure 4.7. The chart is used to analyze the interaction between people and equipment. As indicated in the summary portion of this chart, there is a high proportion of idle time which would probably indicate the use of alternative procedures in the execution of this task. The chart enables the analyst to see the relationships among the activities of the different components in planning such alternatives. 

For the ZW (zero wait) policy idle times (slacks) between consecutively produced batches may appear in all stages including the one that defines the bottleneck. It should be noted that the slacks are only a function of consecutive pairs of batches. Therefore, the slacks for each pair of batches can easily be calculated a priori with the binary variable for any two consecutive batches ... 

The process vessels could provide part or all the necessary storage during their idle time, providing that water of the correct concentration and quantity for their next operation was available at a suitable time. To implement this idea, an inherent storage availability diagram (ISAD) for the set of process vessels can be constructed as shown in Fig. 12.16. The values appearing in brackets are the allowed maximum inlet and outlet concentrations in the processes. For the washes, the value of x has been set at 0.1 kg salt/kg water as mentioned previously. This means that water from the A wash meets the concentration constraints for both the B and C washes. 

This would reduce the cost of inventory space, management, and insurance (it would also result in customers receiving fresher products where this is a factor). Furthermore, in applications where certificates of analysis are required prior to shipping or acceptance, time saved may translate into material holding and/or labor savings (e. g., for truck driver s or tanker crew s idle time awaiting authorization to depart). 

The sequential batch reactor (SBR) consists of a vessel operated under batch conditions according to the time schedule reported in Fig. 3. The symbols Fill, React, Settle, Draw and Idle refer to the typical sequential phases of operation loading, reaction, biophase settling, discharging and the idle time. The reaction period may be split into two sub-phases an anaerobic phase and an aerobic phase. The aerobic sub-phase is devoted to convert products of the azo-dye anaerobic... 

Researchers can use computer programs to test the geometry of many molecular structures and determine their suitability for specific applications. For example, a specialized screen saver can check the shape of hypothetical molecules based on their suitability for cancer treatment. Anyone can upload the screen saver and use a computer s idle time... 

Particles move upwards in a series of discrete fast movements ("jumps"), punctuated by periods of relative inactivity ("idle time" or "quiescent time"). It is during these idle times that the particles are able to sinter in polymer reactors, and control of the length of these periods is necessary to prevent defluidisation by sintering (Seville et al., 1998). 

In a multiproduct plant, all products follow nearly the same path through the process. Only one product, or in a complex case a few products, is produced at one time. Although it is feasible to alternate batches of different products to reduce idle time of equipment, this is rarely, if ever, done to minimize operational error and cross-contamination. Product changeovers are not frequent, especially if extensive cleanout between changeovers is required. 

H and Fm given - Larger B0 will always be favoured (for finite set up times), because the idle time for the plant is reduced and because the capital costs typically increase with capacity by an exponent less than 1 (economy of scale). The optimum value of B0 will depend on constraints 7.14-7.18. 

A global bus system has limited fanout capabilities electrical problems are generally encountered after a relatively low number of processors are added to the system. Also, the global bus system demonstrates the lowest bandwidth capability of all of the systems, since all of the processing elements used the common shared bus. In fact, the operating bandwidth of the global bus system will never reach its theoretical maximum due to the idle time spent while processors access the bus, release the bus, and resolve bus access conflicts ... 

When she retired from indexing the Abstracts, she continued to index the Journal of the Chemical Society and Annual Reports of the Chemical Society. In addition, she indexed Thorpe s Dictionary of Applied Chemistry. Amazingly, these tasks left her with idle time and, her obituarist reported, Le Pla endeavoured to fill it ... 

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