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41.
42.
As a part of a major curriculum study undertaken by the IEEE Computer Society Education Committee in the fall of 1974, a subcommittee surveyed existing curriculum and equipment in both computer science and electrical engineering departments to assess the current situation. The survey was also intended to update the COSINE survey of electrical engineering departments conducted in the fall of 1972.1 相似文献
43.
S. W. Sloan 《International journal for numerical methods in engineering》1981,17(9):1313-1323
This paper describes and efficient method for computing two-dimensional element stiffness matrices. It is a generalization of the algorithm given by Taylor. 1Theory is developed for elements which are loaded under plane stress, plane strain or axisymmetric conditions, and two FORTRAN IV subroutines are included. These subroutines, which are presented in a modular form, are applicable to any type of serendipity, Lagrangian or triangular element, and may be incorporated into a user's library. Alternatively, if desired, the relevant code may be embedded directly into existing stiffness generation routines. 相似文献
44.
Heartworm infected small animal patients are seldom seen in the Netherlands, because the parasite's life cycle cannot be completed in this climate. We report here four cases of the disease in dogs brought to the Netherlands from endemic heartworm areas. The initial diagnosis was based upon this knowledge and clinical signs (low exercise tolerance and coughing). The diagnosis was confirmed by the radiographic finding of variable pulmonary artery enlargement, the electrocardiographic finding of right ventricular hyperptrophy and the presence of microfilariae in the peripheral blood. Treatment resulted in recovery in three of these patients but the fourth died soon after initiation of the therapy. 相似文献
45.
46.
Departments of public health and agriculture in all 50 states of the United States and the District of Columbia were queried in 1977 to determine which of some selected zoonoses are reportable, the method of reporting and the diagnostic stage at which reporting is required. Fifty-three of the 62 diseases on the public health questionnaire were listed as reportable, with hepatitis A required by 49 of the 51 jurisdictions. Telephone reporting was required in nearly 19% of the disease-jurisdiction combinations and, in nearly 55%, reporting was required when the disease first was suspected. Thirty-three of the 41 diseases on the agriculture questionnaire were reportable, with anthrax most frequent. Telephone reporting was required in 30% of the reportable situations and suspected diagnoses were reportable in 54%. The disease lists varied markedly between the public health and agriculture agencies. 相似文献
47.
The results of a 15 months' intensive study on seven flocks of indigenous goats in the Southern Darfur region of the Sudan are discussed in this paper. Birth rates in the region approached 2-1 kids per doe per year. A high total offtake of 28 per cent and a weighted average death rate of about 16-5 per cent were insufficient to offset this high birth rate and flock numbers are increased. Mortality in kids was unrelated to number of births. Weighted average rate of gain for all surviving kids was 87 g per day to 3 months and 67 g per day to 6 months of age. The growth rates of twin and single were similar, but triplet kids grew at a slower rate. For each kilogramme liveweight of breeding females, goats produced 1-5 and 8 times the weight of meat produced by sheep and cattle respectively under the same management and environmental conditions. 相似文献
48.
Palmer RE Sloan PA Xirouchaki C 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2004,362(1819):1195-1205
The deposition onto surfaces of clusters of atoms, prepared and size-selected in the gas phase, is, like atomic or molecular manipulation with the scanning tunnelling microscope, an appealing (but parallel) route to the creation of nanoscale surface features. Both of these seemingly orthogonal approaches allow, in principle, a selected number of atoms to be organized, and both are strongly affected by the lateral thermal diffusion of the constituent atoms, molecules or clusters over the surface. In this sense, the room-temperature (as opposed to cryogenic-temperature) regime can be regarded as a hostile environment for organizing atoms. In this paper we review recent achievements in size-selected cluster deposition and molecular manipulation at room temperature and thus address the fundamental question: with what precision can we organize atoms at room temperature? 相似文献
49.
Characterization of atmospheric aerosols from infrared measurements: simulations, testing, and applications 总被引:2,自引:0,他引:2
An inversion method for the characterization of atmospheric condensed phases from infrared (IR) spectra is described. The method is tested with both synthetic IR spectra and the spectra of particles that flow in a cryogenic flow tube. The method is applied to the IR spectra recorded by the Atmospheric Trace Molecule Spectroscopy instrument carried by the Space Shuttle during three missions in 1992, 1993, and 1994. The volume density and particle size distribution for sulfate aerosol are obtained as a function of altitude. The density and size distribution of ice particles in several cirrus clouds are also retrieved. The probable radius of the ice particles in the high-altitude (10-15-km) cirrus clouds is found to be approximately 6-7 microm. 相似文献
50.
Venous thromboembolism is a leading cause of death and morbidity after extended surgery for early malignancies of the cervix and uterus. Two hundred eighty-one patients who underwent such surgery were retrospectively evaluated for associated risk factors, the incidence of clinically significant thromboembolic complications, and prophylactic value of low-dose heparin and antiembolism stockings. Significant thromboemboli were encountered in 7.8% of patients postoperatively and accounted for the only 4 postoperative deaths. Forty-five percent of patients who developed thromboemboli did so after discharge from the hospital. The preoperative risk factors found to be associated with thromboembolism, in order of statistical significance, were weight in excess of 85.5 kg, advanced clinical stage of malignancy, and radiation therapy within 6 weeks of the operative procedure. Low-dose heparin therapy and the use of antiembolism stockings as preventative measures did not appear to reduce the incidence of thromboembolic complications. A prospective study will be necessary to evaluate definitely the effectiveness of various therapeutic modalities on thromboembolism in gynecologic oncology patients. 相似文献