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131.
All podiatrists are required to know the anatomy and pathophysiology of vascular pathology because it is the leading cause of morbidity and mortality in the western world and a frequent complaint of podiatry patients. Podiatrists have a unique opportunity to reduce the risk of lower extremity vascular pathology, specifically PVD, by encouraging proper diet and exercise in the podiatric patient. Because the next century will bring a population explosion of older people, particular attention must be paid to the multiple and complex disorders that impair functional independence and compromise quality of life--one of the most important disorders being vascular disease. Successful treatment depends on recognition of lower extremity pathology (whether it be arterial, venous, or lymphatic) and the possible suprastructural causes and timely referrals to a vascular specialist when indicated. 相似文献
132.
Don't underestimate the problems of user centredness in software development projectsthere are many!
Torsten Heinbokel Sabine Sonnentag Michael Frese Wolfgang Stolte Felix C. Brodbeck 《Behaviour & Information Technology》1996,15(4):226-236
. On the basis of a longitudinal field study of 29 commercial software development projects, the pros and cons of user centredness in software development were analysed. We looked at two concepts: user participation-an organizational device-involving a user representative in the team, and user orientation-a cognitive-emotional concept-which pertains to positive attitudes towards users. Both were found to be associated with project difficulties relating to process and product quality as well as overall project success. We suggest that the issue is no longer whether or not to involve users, but instead to develop a realistic understanding of the difficulties associated with user centredness. 相似文献
133.
The cost-oriented and sustainable operation of sewer systems requires a comprehensive knowledge about the infiltration situation in the catchment. Owing to the high expenditures for infiltration measurements a reliable transfer of measurement results to other sewer sections would be highly beneficial. Assuming a functional relationship between sewer characteristics and infiltration rates can be identified, such a transfer can be realised by means of classification techniques. In this paper a method is introduced which is based on discriminant analysis and which allows for a transfer of measurement results to similar sub-catchments. The method was applied using two data sets with measured or virtual infiltration rates. It yields acceptable results as a total fraction of 50% to 75% of the investigated sub-catchments was assigned correctly. Furthermore, additional information to assess the results was provided. The quality of the transfer results depends strongly on the homogeneity of the considered sub-catchments. Due to this restriction the practical applicability of the method is restricted. Nevertheless, it might be used as a screening procedure for planning of effective detailed infiltration investigations. 相似文献
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Tribological Processes of the Ball Bearing Steel 100 Cr 6 . Tribomechanical and tribochemical processes of the ball bearing steel 100 Cr 6 were investigated under the influence of ultra high vacuum and different gases by the pin/ring method. The conditions for adhesive wear indicated by prow formation were optimal in ultra high vacuum. Pressures of oxygen, nitrogen and air greater than 10?6 Pa increase the lubrication by formation of thin films, measured by ellipsometry. Increasing nitrogen pressure produces a surface hardening, which can be observed by nitrided wear particles. The presence of pure oxygen creates permanently oxide films with a thickness of 10 nm. This causes abrasive wear. 相似文献
136.
In 137 patients suffering from a local recurrence after primary treatment of breast cancer, the features examined in a retrospective manner included: staging parameters (TNM-criteria), grading according to Bloom and Richardson, growth fraction by Ki67 positive cells as well as immunohistology and biochemical steroidreceptor-expression. In the primary tumours, a good correlation was detected between size of the tumour and lymph-node involvement, between histopathological grading and Ki67 growth fraction and between low histopathological grading and poor immunohistological and biochemical steroidreceptor content. The results of this particular study show that local recurrence is not accompanied by any significant de-differentiation, neither in its histopathological grading nor in its growth fraction nor in its steroidreceptor-status. 相似文献
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The papermaking process can be viewed as a time-varying stochastic system. The purpose of the control is to minimize the variance of moisture and basis weight of the manufactured paper. In the framework of stochastic theory and recently published papers on adaptive control an algorithm has been developed to cover the above-mentioned purpose. The strategy which hardly requires any a priori knowledge about the process is, in fact, a self-adjusting regulator. The central part of the algorithm is a compact identification scheme which gives directly the optimal control action. It is notable that contrary to normal identification and control methods the process dynamics never need to be calculated. The algorithm has been applied to several real-time computer control systems for paper machines. Up to now medium-scale computers have been used, but as the control program is powerful and short, some hundred words in length, it is in fact sufficient to perform the control with a mini-computer. Before the implementation of the algorithm for the above processes, the control system was built around digitalized PI-controllers, the parameters of which were carefully chosen and constant. A great number of comparative tests have been made in order to evaluate the efficiency of the adaptive regulator. The results were so successful that the algorithm has been permanently installed in the systems. The algorithm has not only decreased the output variance but also reduced the losses at quality changes and mill set-ups. Finally, it should be mentioned that the general nature of the algorithm permits application to many other types of processes. 相似文献