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981.
The present study proposes a detection technique for delaminations in a laminated beam. The proposed technique optimizes the spatial distribution of harmonic excitation so as to magnify the difference in response between the delaminated and intact beam. The technique is evaluated by numerical simulation of two-layered aluminum beams. Effects of measurement and geometric noise are included in the analysis. A finite element model for a delaminated composite, based on a layer-wise laminated plate theory is used in conjunction with a step function to simulate delaminations  相似文献   
982.
ADS expert     
ADS Expert is an integrated system that (a) provides suggestions about suitable optimization algorithms for a particular structural optimization problem, (b) it offers explanations and guide lines, in the form of hypertext, that refer to the optimization strategy, optimizer and one dimensional search method, (c) it produces the required gradients for the objective function and the constraints using symbolic differentiation, (d) establishes a direct linking with ADS routines and (e) it monitors the evolution of the optimization process. The system can be used as an educational tool for structural optimization and as an efficient integrated system for small to medium size optimization problems for which the objective function and the constraints are given in the form of explicit functions of the design variables. The system is a Windows application and runs quite satisfactorily on PCs.  相似文献   
983.
Ever since 1974, the cadaver has been embalmed by the arterial embalming method, using pre-embalming fluid with blood clot disperser and cell conditioner for the removal of blood clots and drainage of blood, at the Department of Anatomy of the Kawasaki Medical School. According to this method, the cadavers are always very well fixed so that they can be used for not only anatomical dissection but also research for the vascular system by vasography, kinematics of the joint and other histologic examinations. In this report we have described our embalming procedure concretely and its application to research.  相似文献   
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987.
The geo-electrical measuring technique is frequently used for restoration purposes. However, this technique as developed in geology cannot be used without adaptations. The structure that is analysed has geometrical boundaries which influence the measurements and can lead to errors in the interpretation if they are not taken into account. This is illustrated by practical and theoretical tests. In an extensive test programme other aspects of the technique are also considered, such as the influence of electrode configuration and of moisture content.  相似文献   
988.
In the past anabolic steroids were the first-choice treatment for pancytopenic disorders that were often poorly classified. They are now superseded by other more recently developed methods of treatment--for example bone marrow transplantation and immunosuppression. This contrasts to the authors' experience, and to that of many other haematologists, who have noted anabolic steroid-induced responses in patients who were unsuitable for or unresponsive to the new treatments. Anabolic steroids did not, however, demonstrate an obvious effect in recent controlled trials involving patients with aplastic anaemia. Their use with immunosuppressive treatment is currently under investigation. Although anabolic steroids rarely reverse the course of anaemia in a myelodysplastic syndrome, even a slight haemopoietic improvement is desirable. Children with Fanconi's anaemia may benefit from a reduced transfusion requirement. Uraemic patients may experience significant side effects on standard erythropoietin (epo) treatment. There have been no controlled trials comparing epo versus anabolic steroids or epo versus epo in conjunction with anabolic steroids. Data from uncontrolled studies indicate a better response to anabolic steroids in children and females than in men. In spite of the fact that anabolic steroids have been used for almost 30 years, they should be carefully re-evaluated in scientifically controlled trials to test their efficacy and to compare them with the new treatments. Such trials, however, are impeded by the limited knowledge available with regard to pharmacological parameters and optimal treatment schedules.  相似文献   
989.
The authors present a successful model of industry/university cooperation in establishing a strong power system curriculum in both the graduate and undergraduate level. Numerous long-term and short-term research projects have been developed to satisfy the university mission and to tackle challenging problems facing the power industry. A unique structure for the Clemson University Electric Power Research Association (CUEPRA) has been established to promote electric power system research and to meet the need for a working communication link between the power industry and the academic community. The power industries involvements in the power program at Clemson University and the strategic improvements that have been accomplished in research and education are outlined  相似文献   
990.
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