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21.
Abramatic JF Silverman LM 《IEEE transactions on pattern analysis and machine intelligence》1982,(2):141-149
The restoration of images degraded by an additive white noise is performed by nonlinearly filtering a noisy image. The standard Wiener approach to this problem is modified to take into account the edge information of the image. Various filters of increasing complexity are derived. Experimental results are shown and compared to the standard Wiener filter results and other earlier attempts involving nonstationary filters. 相似文献
22.
We recorded clinical information over a 12-month period on consecutive consultations to the gastroenterology service of the Durham VA Medical Center. Of 902 consultations, 789 were prospectively collected. Eighty-five percent of the patients were between 40 and 70 years old. Seventy-five percent of the referrals were from the internal medicine service. The most frequent reasons for consultation were abdominal pain (19%), GI bleeding (active, 16%; occult, 9%), abnormal results of liver tests (18%), and request for a procedure (11%). Diseases of the liver (32%) and "peptic diseases" (30%) were the most common diagnoses. One or more procedures were done in 71% of consultations. When these data are compared with those of a practicing gastroenterologist, using an identical instrument, it is apparent that trainees' experience with structurally identifiable gastroenterologic disease and with a variety of procedures was similar in scope. There were, however, differences in that the physicians at the VA saw substantially fewer patients with so-called "functional" illness. If these data are applicable to other VA Medical Centers, then the training of physicians in gastroenterology at a VA Medical Center should probably be broadened. 相似文献
23.
By using the arterial and venous phases of an anterior cerebral perfusion study, which showed downward displacement of the sagittal sinus, and the finding of a "rim" on the delayed scans, the specific diagnosis of epidural hematoma was established. 相似文献
24.
In response to the increasing trend toward community health care, a model of training that prepares students for community practice was incorporated into the occupational therapy curriculum at the University of Southern California. During academic training students are placed in a part-time community assignment where no occupational therapy services are offered. Training students for the role of community health specialist produces a dilemma for curriculum design. A balance must be achieved between providing traditional clinical content and providing the knowledge and expertise necessary for community practice. However, this training is considered necessary for maintaining the viability of the profession in a changing health system. Significantly, during the four-year period using this model, many graduates have sought employment in "nontraditional" community roles. 相似文献
25.
Correia Christopher J.; Sigmon Stacey C.; Silverman Kenneth; Bigelow George; Stitzer Maxine L. 《Canadian Metallurgical Quarterly》2005,13(3):253
Studies on the use of shaping procedures to increase rates of cocaine abstinence have produced promising results. This study used a Brief Abstinence Test to examine the impact of reinforcement for initial reductions in cocaine use on a subsequent abstinence reinforcement test. Methadone maintenance patients showing evidence of cocaine use were exposed to two 1-week reinforcement conditions. During the shaping condition, participants could earn $50 vouchers on Wednesday and Friday for meeting quantitative urinalysis criteria and a $100 voucher on the following Monday for meeting the more stringent qualitative criteria. During the terminal condition, only the $100 earning opportunity for meeting the qualitative criteria was provided. Participants were more likely to meet the qualitative reinforcement criteria on Wednesday and Friday in the shaping condition than in the terminal condition. However, contrary to the initial hypothesis, the shaping reinforcement condition did not increase rates of abstinence on the final abstinence test. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
26.
Review declaring pleasant surprise with this relatively short book on stalking. It contains 164 pages of text, and provides a thorough context for understanding and treating stalking behavior, including a focus on both victim and perpetrator. The book is divided into five chapters. The first of these defines the nature of stalking behavior. Stalking is defined as harmful conduct, which involves unwanted communication and repeated unwanted intrusion by one individual upon another. The review notes that stalking behavior has three defining characteristics--(a) relentless and persistent contact, which is (b) unwanted and (c) adverse to the recipient. It is further observed that there is no single motive for stalking, nor any specific psychological profile for the personality of stalkers. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
27.
Maurice L. Huggins K.uan-Ran Sun Alexander Silverman 《Journal of the American Ceramic Society》1943,26(12):393-398
The difficulty of defining the vitreous state in a rigorous manner, the existence of many borderline cases, and the theoretical requirements which must be met if a substance is to be vitreous are discussed. Silicate glasses and certain other typical classes of vitreous substances are treated in some detail with especial reference to the relation between their structures and vitreous properties. 相似文献
28.
W. B. Silverman 《Journal of the American Ceramic Society》1942,25(6):168-173
The results of experiments with synthetic cords indicate that surface tension is the most important factor in the disappearance of cords. The viscosity relations of the glasses do not correlate with the tendency to form inhomogeneities. Fibers of higher surface tension than the base glass with which it is fused form cords, and those of lower surface tension do not. Compositions that are high in RO or A1208 tend to form inhomogeneities in glasses which have a lower content of these two constituents. 相似文献
29.
Assuming from a consideration of silicate minerals that aluminum should replace silicon in silicates, the authors investigated the system Na2O-CaO-SiO2-Al2O3. Densities and refractive indices have been determined and molecular refractions have been calculated. Partial molecular refractivities of Al2O3 indicate a coordination number of 4 for aluminum and deviate appreciably from values for compounds in which aluminum has a coordination number of 6. Interionic distances have been calculated for Si—O and Al—O. As a result of these studies, it is concluded that the aluminum atom isomorphously replaces the silicon atom in the random fetrahedral network. With this replacement, Ca++ can increasingly replace Na+ in the interstices of the open structure. 相似文献
30.
Louis Silverman 《Journal of the American Oil Chemists' Society》1947,24(1):13-14
Soap and soap flakes are decomposed by nitricperchloric acid, with the aid of a catalyst. Silica is then dehydrated, filtered
off, and determined in the usual manner. 相似文献