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AMAZON multi-meters discounts AMAZON oscilloscope discounts No one is untouched by computer automation. Like it or not, the computer controls much of our environment and touches our lives daily. The ubiquitous computer runs the phone system, processes bank checks, and even plays games. Nearly every engineer has had an opportunity for hands-on computer experience. But computer technology is evolving so rapidly that it is hard to understand what is currently possible, much less extrapolate what computers will eventually be capable of performing. An information explosion is occurring, where the volume of data being collected, stored, formatted, and presented to each of us daily is far more than can be meaningfully assimilated. Maintenance engineering, as currently performed, has had limited benefit of computer automation. Many of the advances made in computer applications have yet to touch, or be touched by, the plant engineer. This section will introduce the latest technology and newest applications of the computer, paying particular attention to the implications of these advances as they affect the maintenance engineer. The intent is to expand awareness of the potential uses of computer technology for engineers facing the realities of day-to-day maintenance work. As such, it will be demonstrated that the computer is today a practical maintenance tool, not a science fiction fantasy, and will become part of every maintenance engineer's experience in the years to come. ELEMENTS OF TODAY'S COMPUTER SYSTEMS Computing comprises two primary elements-hardware and software-that have been the basis of computer technology since the days of ENIAC, the first digital computer. Hardware, of course, refers to the computer equipment, including the actual computer, or central processing unit (CPU), and the peripherals that work in conjunction with the CPU. Software, on the other hand, is the programming that makes the computer function and perform useful work. Programmed instructions are still required to put the most sophisticated hardware available today through its paces, turning useless metal into a practical, functional tool. Hardware, in its several forms, and software technology will be briefly reviewed before examining the myriad of work that computer systems can perform. HARDWARE Central Processor (CPU) The CPU is the brain of the system. But it would be wrong to think of a computer only in terms of its CPU, just as it would be wrong to think of a person as merely a brain. Computer peripherals, the limbs and senses of the system, are essential to a fully functional system and, in many ways, are more responsible for determining the full capabilities of the computer than just the size of the CPU. Modern computer CPUs are enormously powerful and inconceivably fast. Cycle times, the time it takes for the processor to complete one instruction "cycle," are now measured in millionths of a second, or in "nanoseconds." The largest computers process on the order of tens of millions of instructions per second. During the past decade, computer power has experienced a precipitous decline in cost. The nerve cells of the computer's brain-silicon chips-have, thanks to impressive strides in manufacturing and quality control, become available at low prices of just a few dollars. Very large system integration (VLSI) has significantly reduced the costs of computer processors and memory chips. In 1979, for example, a memory chip that could store 16,000 characters (16 kilobytes or kbytes) of data was the computer industry standard; today that standard is a 64-kbyte chip, and the 256-kbyte chips and larger are available. This trend reflects a 16-fold improvement in chip performance in just over 5 years at virtually the same unit cost per chip. An additional benefit of this improvement is a lowering of power consumption and heat generation. The first computers used vacuum tubes, were housed in immense rooms, and generated enough heat to warm a house in the winter. Use of transistors, beginning in the late 1950s, reduced the power and space needs and cut heat production, although not enough to eliminate the need for a special temperature-controlled environment. VLSI technology has further cut power and space needs because, as circuits become more compact, and hence elements are closer together, electricity gets to the next component faster. This increases computer performance (i.e., the computer is faster), and, because less travel distance also means less resistance, circuits generate much less heat. Modern processors are much more powerful, and yet far more cost-effective, than their predecessors. Input/Output Devices In the past, data were entered mainly by reading 80-column, keypunched cards into the computer. Today, a variety of input devices are used, ranging from typewriter-like keyboards and cathode-ray tubes (CRTs) to optical character recognition (used on IRS tax forms), magnetic ink (used on bank checks), and magnetic stripes (used in supermarket checkout systems). Further, computer recognition of voice input is just around the technological corner. Impact printers used to be the only output device available. But impact printers, which create a character image by striking type to an ink ribbon against paper, were slow and prone to mechanical failure. Not only are modern impact printers faster and, thankfully, quieter, they are far more reliable because of fewer moving parts and numerous mechanical refinements. Even so, other high-speed output devices are even faster and virtually silent: matrix printers which form characters by producing a series of dots on the page and which can produce a variety of character sizes and styles; ink-jet printers which "draw" a character with a computer-directed stream of ink; laser printers which produce an entire page of type and/or graphics at a time by bonding ink particles to electrically charged paper; and microfiche which does not use paper at all, but photographs a page onto microfilm. In addition, computer pen plotters can draw anything, from charts and graphs to enormous diagrams and blueprints of an entire plant. Storage Devices Computer storage devices have improved tremendously since slow, low-density tape drives were the norm. Today's high-speed, high-volume tape units are self-loading and store six times the amount of data per inch of magnetic tape as 10 years ago. Yet even so, tapes are no longer the basic computer storage device, having been replaced by the far more flexible disk-drive unit as the storage standard bearer. Disk-drive technology has moved in two different directions. For large computers, disk drives have become super-high-volume units, storing more data per drive, at a lower per-unit cost, than ever thought possible. The physical storage elements for these units are no longer portable, remaining fixed in one location for unsurpassed reliability. Conversely, disk storage space for the new breed of small, lightweight systems and microcomputers is smaller and less sensitive to accidental abuse, but is capable of storing a fairly large amount of data. A new storage technology that stores data optically, instead of as digital impulses, will markedly increase the density and speed of disk storage devices by the next decade. Moreover, a rapidly booming technology in small and personal computers has brought about increased use of hard disks or a shift toward such usage. Communications Perhaps the most startling development in computer technology has occurred in the field of data communications. Once a slow, error-prone process, systems now reliably "talk" at high speeds to their own remote input and output devices, as well as to other systems. Data can now be shared efficiently among many systems, and users can have ready access to vast stores of information. Local area networks (LANs) are an important area of progress in data communications. A LAN allows several local-meaning in one plant or factory-devices, such as microcomputers and other equipment, to communicate with one another. LANs simplify the process of passing information among locations and allow data collected on one machine to be shared with other users needing access. SOFTWARE Computer systems rely, in varying degrees, on four separate but interrelated types of software. The operating system, the first type, is the most fundamental set of programs and tells the computer hard ware how to function and what to do. For example, it provides instructions on how the computer's memory is to be used and shared by competing programs, how data are to be transferred to other hardware devices, and how data will be stored and retrieved. This software is a system prerequisite and is often proprietary to a given hardware manufacturer. The second type, systems software, manages major tasks that the computer can be used to per form. Systems software could, for example, manage a large database or control communications. It is not unique to a manufacturer, but is often machine-specific in that it is provided in one specific version for the type of equipment being used. Languages are the third type of software, and they make it possible to program the computer to do specific tasks or functions. Computer languages let a programmer write software which the computer translates into its own internal instructions. A wide range of languages have proliferated, some generic to all sizes and manufacturers of computers, some very focused and limited to a single machine. The fourth and last type is application software. It enables users to perform functions on a computer without having to program it themselves. The programming effort has been done by others, with the resulting software designed to execute a specific set of business functions or solve user needs. Examples of application software include word processing, financial planning, and computer-aided design. MAINFRAMES/MINIS/MICROS As computer usage has grown, the computer itself, per unit of work performed, has actually gotten smaller. In the early 1970s, a large or mainframe CPU could store 256 kbytes of data in its internal memory at a cost of about $100,000. It required a special, air-conditioned environment and consumed substantial electrical power. As a basis of comparison consider a 1984 computer with 256 kbytes. At that time storage costs were well below $2000. The unit sat on a desktop with no special environment, and used normal 110-V power. Today's equivalent of yesterday's mainframe would be called a microcomputer. Indeed, that same computer is completely portable, able to sit on a lap and travel anywhere because it is powered by batteries and weighs under 10 lb. Computers are often classified as either mainframes, minicomputers, or microcomputers depending, in part, on their size and cost. Mainframes are still enormous machines requiring special power sources and air-conditioning. But these machines now have millions of characters of internal storage, manage hundreds of concurrent functions and peripheral devices, process millions of transactions and enormous databases, and cost millions of dollars. They are most often manufactured by companies such as IBM, Honeywell, and Sperry, as well as by new entrants such as Amdahl. Minicomputers were pioneered by Digital Equipment Corporation (DEC) in the 1960s as relatively small, inexpensive machines that could be dedicated to a specific function, such as time-sharing or controlling a piece of machinery. Modern minis have grown up to resemble small mainframes. They cost tens of thousands of dollars, require some environmental improvements, manage multiple tasks and devices, and handle smaller processing demands such as those of a small business. Still manufactured by DEC, which dominates the market, they are also supplied by companies such as Hewlett Packard, Data General, and Prime, not to mention IBM. Microcomputers first appeared in the 1970s as hobbyist toys, but gained legitimacy in business due to Apple Computer's reliable hardware and a software package for financial planning called VisiCalc. The winning combination of these two pace-setting products enabled micros to become efficient management tools for performing particular tasks and functions without having to go to the central computer resource. Micros now cost well under $3000 for complete business systems, are capable of managing a single task at a time, and require no special environmental considerations. Literally hundreds of manufacturers have entered the market in addition to Apple and IBM. COMPUTER ECONOMICS 101 The underlying economics of computing are changing almost as quickly as computer technology. When computers were unwieldy, expensive, and required special care plus special environments, it was economically reasonable to centralize this resource and allow many users to share it. Communications lines tied engineers' inexpensive terminals to an expensive, shared computer resource, and users would program their own routines or access a small library of packaged programs offered by the system. Today, shared computers have evolved into either repositories for large databases and information that users may want to access, but need not own, or as central transaction processors for huge applications such as banking and airline reservation systems. In their place, small, even portable, computers are directly in the hands of users providing virtually unlimited access at very little cost. These machines allow managers to exploit the power of the computer and to access central databases for information that improves and streamlines maintenance functions. Another consequence of the increase in computing, however, is a greater demand for programmers, analysts, and other computer technicians. Raw computing power is increasing at a rate of 50 percent each year, but programmer productivity is not. As always is the result when demand out strips availability, the price of the scarce resource increases in kind. Computer personnel salaries have grown dramatically, so that today's cost of programming has increased greatly per unit of useful work. As a result, computer economics have turned virtually inside out. Software, truly the workhorse of computing, can often cost much more than the hardware on which it runs. It is no longer assumed, perhaps not even justifiable, that computer software will be developed from scratch exclusively by and for the user. More likely, the user will buy a packaged, off-the-shelf solution and, if absolutely necessary, adapt the package to his specific set of requirements. There is one further and dramatic result of the evolution in computer economics. In the early days of automation, the most basic justification for computers was cost-cutting the cost of a largely clerical job by computerizing it, much like factory automation cut the cost of producing products. The obvious, manually intensive jobs, such as accounting, were the earliest areas automated. Later, computers were used to do more than just lower costs-they helped improve service and provide better information. Examples of this type of computer automation are inventory control and financial planning. Now, with current computer economics, technology is enabling creation of new forms of service which could not have existed before. Rather than automating the old functions, computers are being used to invent new products. Examples of this phenomenon are bank automated teller machines, which have added a new dimension to bank customer convenience and access without increasing staff, and computer-controlled factories, which tremendously expand management's control of and information from the plant floor without adding people to collect the data. BENEFITS OF COMPUTERIZATION With increased availability and affordability of computer resources, the benefits of computerization are becoming accessible to more areas of the plant and factory. Although the functions performed and the advantages promised vary, in general the benefits of computer-automated maintenance can be classified into four basic types: _ Reduced costs _ Greater access to information _ Better planning _ Increased control Reduced Costs. The oldest and most frequently cited benefit of computerization is lower cost, either because the same work can be done with less effort, or because more work can be done with the same effort. Either way, the computer cuts the cost per unit of work accomplished, saving the plant money. Manually intensive functions requiring repetitive clerical tasks are obvious opportunities for this type of computer solution. Typing work orders, for example, can be streamlined with word processing capabilities that store standard documents and enable changes to be made simply by typing the revisions. The result is that more work orders can be produced by the typist, thereby lowering the cost. Computerization also beneficially affects maintenance work itself. Using the computer as a job planning tool improves the efficiency of the planner, reduces errors, and can even streamline the maintenance work itself. Standard job plans can be stored on computer disk and easily modified for the specific circumstances of the job. The computer cuts the planner's time and, because the standard plan has all the parts and tools identified for successfully performing the maintenance job, ensures that the job is done right and with a minimum of backtracking to get forgotten items. The computer can also be used to determine the most cost-effective preventive maintenance interval, to efficiently manage inventories of parts and stores, and to reduce the expense of training new personnel. Greater Access to Information. Often, useful-perhaps even invaluable-information is either unavailable or very cumbersome and time-consuming to obtain. The computer can help make information readily accessible by storing data in retrievable form and by facilitating data manipulation and reporting. Information can be obtained on a regular basis in the form of periodic reports, but it can also be accessed or provided on an ad hoc basis from a computer screen. Data-management software, in conjunction with high-speed computer disk drives, can easily maintain large databases which are widely accessible and provide a wide range of useful information in a user-selected format. A database of plant equipment, for example, can easily and quickly be interrogated for answers to questions such as: _ Which machines (by machine number and location) were built by the same manufacturer? _ Which parts (by manufacturer and part number) are shared by multiple machines? _ Which machines (by area, function, and machine number) are due for preventive maintenance? In addition, by adding data on repairs and maintenance, this same database could provide a complete machine history with information on the frequency, timing, and cost of maintenance. Better Planning. Greater access to information, coupled with the speed and flexibility of the computer, enables maintenance management to do a better job of planning and coordinating their efforts. Regular planning tasks, such as budgets and manpower plans, as well as nonrecurring plans, such as preventive-maintenance interval determination and inventory-reordering point analysis, can be streamlined and improved significantly. Plans are quickly constructed. Changes are easily accommodated. More versions can be tested and evaluated before a final approach is accepted. The computer is also a powerful tool for simulating a proposed plan so that unanticipated flaws can be ironed out prior to implementation. Increased Control. The combination of these benefits leads to a further benefit of computerization: increased control over maintenance operations. Streamlining manual, clerical tasks; accessing information heretofore impossible to obtain quickly and easily; and better operations planning result in improved management control of day-to-day functions. With these resources, the plant or maintenance engineer is better informed and better able to take action before problems arise, rather than waiting passively for the next crisis. APPLICATIONS Having now seen generally what computer hardware and software can do and their potential maintenance management benefits, specific applications of computers in maintenance engineering can now be examined. The seven functions described below are readily automated within existing technology. In some cases, the task is already being performed with computer automation, although not necessarily by the maintenance department. In other instances, the task could be computerized easily using existing capabilities, but has not yet been very widely accepted in maintenance engineering. Office Automation. An office performs a broad range of functions, all basically routine and clerical in nature, which readily lend themselves to computer automation. Among these tasks, the most significant ones for maintenance engineers are word processing, to speed typing and document editing; business graphics, to provide graphs and charts for reports; and electronic mail, to speed the flow of memos and other correspondence. Of all office-automation functions, word processing is by far the most prevalent and serves as the core of the modern, computerized office. Word processing automates secretarial functions by speeding typing and storing documents in electronic form. The documents can be easily retrieved, edited, reformatted, and combined with other documents, before the final piece is produced, all without having to completely retype material. Standard documents, such as standard work orders, can be stored and retrieved as necessary, with dates, locations, and so forth modified to fit the specific circum stances, again without retyping the document. Word processing is, of course, ideal for streamlining production of correspondence, maintenance reports, bid specifications, and other routine documents subject to frequent change and/or repeated use. Plus, by adding new capabilities, including automatic spelling checkers, word processing is even more effective at reducing costs and improving the quality of routine typing tasks. With the addition of business graphics, reports can be made more meaningful and communicative. Simple line graphics and bar and pie charts are produced by the computer and easily incorporated in documents produced by word processing. Electronic mail can quickly and efficiently communicate information to other areas of a plant, or even to other plants. One typed document is electronically replicated as many times as needed to broadcast the material to all designated locations and people, reducing typing, copying, handling, and postage costs. Computer-Aided Design. The size, speed, and declining cost of modern computers has allowed computer-aided design (CAD), which consumes large amounts of computer resources, to become practical and cost-effective. Using the computer as a design tool, plant and factory designers enter and store plan data in the system for analysis, review, and modification. The computer can ensure that all plans are complete and consistent, and can identify potential problem areas from both a construction and maintenance perspective. Standard details can be stored for easy incorporation in the plan drawings as appropriate. Design time is reduced, engineering changes are simplified, and manual drafting is nearly eliminated because the computer produces final drawings on a special pen-plotter output device. Since the entire interrelated plan exists as a computer model, maintenance engineers and job planners can use the computer to examine an area thoroughly before writing the plan and sending in mechanics. They can review their approach to ensure that adequate manpower and proper tools are on hand. And if the parts list is also automated, they can be certain in advance that the right parts are available for the job. Lastly, a computer-aided approach also simplifies the problem of storing design and as-built drawings-they can be left in computer disk storage until needed. Since the only set of drawings that exist are necessarily the right ones, errors from using old, outdated drawings are a thing of the past. Accounting and Financial Management. Computer tools simplify the process of developing and maintaining budgets and financial controls. Using computer-based planning tools, maintenance engineers can create detailed manpower and dollar budgets for the period and examine as many alter native approaches as they choose. The budget is electronically stored and easily updated as circumstances change throughout the budget cycle. Utilizing additional computer software, expenses can be tracked and compared with the budget to determine variances and to adjust plans when staffing and dollar overruns occur. Cost-accounting software enables the maintenance engineer to track job costs versus estimates and to identify, and correct where appropriate, incorrect assumptions or methods. Further, these accounting tools can be used to charge the proper department for the work performed, if the maintenance function is so structured. Inventory Control. Inventories of equipment, parts, and stores are easily maintained in a computer database. Equipment records can contain all data about the machines, including parts lists and even maintenance records, making detailed equipment information readily accessible to authorized computer or terminal devices throughout the facility. Parts and stores inventory systems track volumes on hand, locations, consumption and shrinkage, reorder points, and unit costs. They can even be used to automatically trigger reorders and to maintain parts lists and manufacturers of acceptable substitute items. Personnel Recordkeeping. Personnel records are also easily maintained as a computer database, similar to an inventory system. Up-to-date records on all maintenance staff can be quickly interrogated by a job planner to determine which employees have certain requisite skills, familiarity with particular equipment, or are eligible for overtime. The files can also be expanded to track all time worked by the employee, and, in conjunction with salary data, can provide cost figures for input to a detailed job-cost accounting system. Job Planning. The computer can simplify the process of job planning significantly. First, if a standard job plan already exists, the plan can be retrieved and tailored to the specific task with minimal effort. Such standard plans would identify parts, tools, and manpower requirements as well as define the work to be done, eliminating the guesswork and possible errors of writing a plan from scratch. Second, if a new job plan must be developed, the planner can access all the information he needs from the various computer-stored files: equipment parts lists and maintenance histories; parts and tools inventory and location data; and personnel records concerning skills and eligibility for overtime. Third, job estimates can be tracked versus actual time and dollar figures to assess the plan's usefulness and to determine how the plan can be further refined before it is stored for future use. Training. Lastly, the computer can function as an interactive learning tool providing detailed maintenance training for new employees, updates and refreshers on new equipment and maintenance techniques for current employees, and review and background material on specific equipment or less frequently performed tasks. The training is self-paced, interactive, and designed to keep the employee involved and interested. Computer-aided instruction is more efficient than a class with an instructor because it can be used at any time for any number of students and the information is retained longer than if the employee were merely given a book to read on the subject. PREV | NEXT | Article Index | HOME |