Up the Operations

Most of the interesting problems — the ones that you find in real life — are made up of words describing a situation or question that is solved using one or more operations. The best problems are those that involve more than one operation. Okay, that s from my perspective, but I m going to try to win you over to my side with some scintillating examples. 

When more than one operation is involved, you need to be cautious about which operations to use and in what order to use them. Making decisions about the operations and the order requires a mixture of good old common sense and a willingness to tackle a problem, slightly seasoned with some good old math rules. 

One challenge of dealing with two or more operations is determining the order in which you do these operations. Sometimes the path or order is clear cut. Sometimes the problem is loaded with pitfalls or opportunities to flub. You need to keep in mind the order of operations from algebra when doing multiple operations in story problems. 

The order of operations says that, when you have more than one operation to do, first perform any powers or roots, then do any multiplication or division, and end by doing any addition or subtraction. The order of operations can be interrupted, though, by parentheses or brackets or other grouping symbols. 

Here are some examples of using the order of operations  

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Most rigs are now fitted with a system whereby the drill string is rotated by a drive mechanism in the mast rather than by the rotary table at rig floor level. Thus 90 foot sections can be drilled before connections need to be made, and the drill string can be rotated while pulling out of the hole in 90 foot sections. This improved system, which speeds up the operation and allows better reaming of the hole is known as top drive. 

To be effective, this method must be carried out on samples which have been blanched, and upon peas from which the skins have been removed. The heat applied in blanching drives off gases entrapped in the tissues, and removal of the skins is required to remove air that may be entrapped under them, although it materially slows up the operation and makes it very tedious. In order that there may be consistency in grading, the test must be conducted under closely standardized conditions of temperature and solution concentration. This becomes of considerable importance in borderline cases, and failure to take it into consideration no doubt accounts for some of the inconsistency in results experienced by the industry. The test is not a true measure of tenderness, in that it accounts for variation in skin texture only in so far as maturity affects skin texture. Skin texture is affected by factors other than maturity (4). Other methods for the estimation of maturity based upon density or specific gravity have been suggested by Jodidi (16) and by Lee (22). 

Well A.. This oil producer was to be converted into a water injector. Though its production period had been relatively smooth, with no sign of production damage build-up, the operator wanted to be sure to obtain a maximum injectivity index before initiating water injection. The well data and acid job main parameters are summarized in Table I. 

To solve this problem a version of the model has been installed on a PC in the plant control room. Every time a cell is set-up the operators run the model and enter the prevailing plant load, total brine feed and brine temperature. They are then given a recommended cell k-factor profile to achieve the target gap. 

In either case, whether we do the 90° pulse first or the 13C 90° pulse first, we are simply choosing the order of the two processes (Fig. 7.27) the lH operator (Ix) in the product moves from the x-y plane to the z axis (lH 90° pulse) and the 13C operator (Sz) in the product moves from the z axis to the x-y plane (13C 90° pulse). We can bump up the operator to the z axis first, resulting in both operators on the z axis, and then knock down the 13C operator to the x-y plane. Alternatively, we can first knock down the 13C operator from the z axis to the x-y plane, resulting in both operators in the product in the x-y plane (MQC), and then bump up the operator from the x-y plane to the... 

Slight competition also speeds up the operation appreciably. 

B, D. The two files that are used by DOS to configure a computer are AUTOEXEC.BAT and CONFIG.SYS. In general, the CONFIG.SYS file sets up the operating system environment, and the AUTOEXEC.BAT file sets up the user environment. 

The optimal length-to-diameter ratio of the collimating column should be estabhshed in order to avoid waste of materials as well as to achieve the desired uniformity of UV rays. A warm-up period and stabilization of ultraviolet lamp are important to allow the lamp to reach its optimal temperature for each start-up. The operating temperatures of a MP UV lamp and a LP UV lamp are typically 600°C or higher and the neighborhood of 50-60°C, respectively. Distance between collimating column and surface of liquid should be less than 2.5 cm (24). The depth of microbial suspension should be on the order of 1 cm. 

One promising area of investigation is the use of ultrasound to speed up the operating rates of existing aqueous electroplating systems which were not economically viable in the past. These systems can then become feasible and Fitch [102] has described the use of aqueous based compounds such as sodium salts (e.g. hydroxide, silicate, phosphate, carbonate, and borate) as an alternative to the more toxic materials commonly used. These inorganic compounds are inexpensive, readily available, and highly effective in the presence of ultrasound. 

Junk and chain mail on the Internet - do not get involved in distributing junk or chain mail (the electronic equivalent of chain letters). This activity is likely to be against your institute s rules for the use of its computer facilities because it can foul up the operation of networks. 

From the temperature build-up, the operator observed a plugging temperature rise and therefore an increase in the impurities... 

Nor should technical information be allowed to clutter up the operating instructions themselves. A simple way to decide whether a sentence belongs in the procedures or to an information manual is to see if the sentence has the form of an instruction, i.e., does the sentence start with a verb in the imperative tense Sentences such as the following belong in the procedures because they are all do items. 

Benefit could accrue from reducing the in reactor working time by-speeding up the operations at present carried out by the manually operated manipulators and hence increasing the station availability above the present lifetime figure of 82% vhich is already among the top ten reactors in the world. 

However it is worth considering that everyday activity of an organisation is connected only with some probability of occurrence of threats effects in the operational aims achievement. Therefore the best way to take up the operational risk is system management. It should be directed towards the prevention of the effects of quality, environmental and occupational safety threats. 

The original concept for neutron monitoring includes three systems. Source range. Intermediate range and Power range. During start-up the operator has to select and operate... 

As with many positive or operational readiness trees, the first tier addresses the personnel, procedures, and plant and hardware that comprise the system. The only personnel for this system is the individual preparing the tree who will be the sole operator of the system therefore, it is represented by self shown as a base event. Procedures for this system consist primarily of the operating and maintenance instructions provided with the hardware and software. Because several sets of instructions may be involved, instructions cannot appropriately be shown as a base event, yet the instructions are not the focus of the exercise. Therefore, they are shown as an undeveloped terminal event. The real focus of the effort is the plant and hardware, in this case, the home computer. The home computer facilities and equipment consist primarily of the computer hardware and the software to make it operate. Other items are also required, like a room to set up the operation, furniture, and electrical outlets, but again they are not the focus of the effort and are therefore shown simply as other in an undeveloped terminal event symbol. 

The older filters consisted of a timber frame supporting a cloth placed above a suitable storage tank. This method was extremely slow and nowadays the application of pressure across the filter cloth is usually employed to speed up the operation. Plate and frame filters (Fig. 3.6) which employ this principle are usually constructed of timber, cast iron, or rubber-covered steel. The plates and frames have the same outside shape, the plates support the filter cloth against a ribbed surface and the frames accumulate the solids. The number of plates and frames used may be varied, and their order of assembly is often indicated by markings stamped on the outer edges. The slurry is fed into the press by a pump and when the specified pressure is... 

Brief Description of Incident This facility manufactured powder coatings and paint additives by a process using free-radical polymerization of acrylic monomers in flammable solvents. A customer requested more of an additive than the facility would normally make in a single batch, so managers decided to scale up the operation to produce the required amount for the order. The managers and most operators in this plant had been with the plant less than a year, and none of them had previous experience in manufacturing polymers. 

At start-up, the operator is given three options manual, dress and grind cycle. 

The operator is not the problem. It is the error-provocative system that sets up the operator to make errors. Others have also said that expecting humans to adapt to the system does not work. The proper approach is to adapt the system to the human. 

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