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Show Future for Coal: Mixture Of Optomism and Caution The outlook for the U.S. coal industry during the 1980s is a dynamic mixture of optimism and caution, according to J. Alan Coe, assistant vice president - marketing, Consolidation Coal Company. Addressing a conference of the American Institute of Mining Engineers, here, he said that while North American utilities continue to provide the U.S. coal industry with its largest market and its greatest potential for growth, significant expansion in the industrial and export markets also is anticipated during the next decade. However, the high interest rates, restrained economic growth and uncertainty over environmental regulations have distorted recent coal industry growth forecasts, especially those involving the electric utility industry. "The most serious energy problem facing us in the 1980s is the financial condition of our electric utilities," Cope said. "Approximately $350 billion will need to be invested in electric plants in this decade for capital improvements. "But utilities' cash earnings are continuing to provide for less generation of funds than is required, forcing utilities to borrow additional capital at high interest rates." He explained that the situation is causing utilites to continue operating oil-fired generating stations and passing the higher costs onto the consumer, rather than coverting to coal. Cope foresees a 3.7 percent growth rate in the utility market for coal during the decade, bringing the yearly total to 830 million tons by 1990. In the industrial market for coal, Cope predicts a turnaround from the decline which prevailed during most of the last 30 years to a sharp increase in the next 10 years. This will occur despite uncertainties because of environmental concerns and the uncertain nature of natural gas price decontrol. "In industry, the use of coal has declined and with it the infrastructure," he explained. "Because industry uses smaller boilers, the relative economics of coal versus other active fuels are less favorable than they are for the large utilities." He believes that the increasing impact of new technology in coal handling and combustion especially fluidized bed com-busters will improve industrial market growth during ( Con tinned on Page 8) Coal Future: Mixture Of Optomism & Caution (Continued from Page 1 ) filtering," the technique is an extension of the subtraction imaging concepts that recently have made intravenous angiography a clinical reality. "It's been used on 40 patients and the results are extremely promising," says Robert A. Kruger, Ph.D., research assistant professor of radiology who conceived the instrumentation. "Filtering is an especially valuable tool in the diagnosis and treatment of atherosclerosis, and it can also be used to assess and diagnose cardiac illness and to monitor patients who've had heart problems." Dr. Kruger, a physicist, says this filtering technique is very similar to conventional digital subtraction angiography, but has fewer drawbacks and is simpler and potentially less expensive to implement. "In digital substraction angiography, the image of a body part is first 'masked' and stored as a series of numbers. Contrast materials then are injected, after which time a series of images is stored and sequentially subtracted from the 'mask,' " explains Dr. Kruger. "For the procedure to be successful, the patient must remain absolutely still, and there must be an intense enough beam of x-rays that there's little noise interference, the same dosage as a regular x-ray would require." Substraction angiography is effective if the patient doesn't move between the time the mask is taken and the time the contrast material reaches the artery (10-20 seconds). In the difference between the two images, bones, organs and other extraneous structures are eliminated, leaving a very dim image of the arteries, which can then be contrast enhanced (made brighter) by computer. "Our instrumentation does not subtract the two images, but the filtering makes it look as if it had. Filtering isolates the flow of contrast material by virtue of a prior knowledge bf its probable variation with time," says Dr. Kruger. "This continuous recursive filtering can be 'tuned' to isolate cardiovascular dynamics which vary at known rates. Such processing does not require taking an explicit mask image in order to isolate and enhance contrast material flowing through the artieres. "For example, filtering angiography can isolate image variation that changes every five seconds or so," explains Dr. Kruger. "It removes events that vary more slowly, such as stationary anatomical parts, or faster, such as cardiac motion." The Utah physicist says filtering has several advan tages over subtraction angiography. "It uses a lower dose of radiation. Filtering angiography costs only half as much, requires a far less sophisticated fluoroscopy system, and the necessary equipment (the prototype was produced by Thompson-CFS Broadcast, Inc., manufacturers of video processing equipment) can be retrofitted to existing equipment," says Dr. Kruger. When filtering angiography equipment is manufactured it will be portable, eliminating the need for a special purpose x-ray room. Video tape studies can be performed, or the video image can be made into a transparency that looks like an x-ray. Another advantage, according to Dr. Kruger, is that technicians can see the finished product as the procedure evolves x-rays can be left on continuously to create a moving picture of changes going on inside the artery. "Intravenous angiography using filtering techniques is most successful on the head, neck and peripheral arteries," says Dr. Kruger. "It is somewhat less effective in areas where there's a greater chance of unwanted motion, such as the lung, or the abdomen, where even a small amount of bowel gas can cause motion artifacts." |