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111.
One of the most important uses of (interactive) computer graphics is as one of the tools available to a User Interface Management System (UIMS) for a variety of user-computer environments (UCE). Typical UCEs in vogue are Programming Support Environments (PSE), Expert System Builders (ESB), Office Automation systems (OAS). This paper concentrates on the conceptual relationship that exists between the users on the one hand and computer systems on the other. Such relationships are to be seen in the context of specific application domains. The two standards, GKS and Ada, are chosen to be the background against which the argument for a Software Methodology based on the Abstract Data Type approach, is presented. This has significant implications for a GKS binding to Ada and the development of GKS application software written in Ada. A collection of colour models is considered in detail.
Ada(R) is a registered trademark of the U.S. Government, Ada Joint Program Office. 相似文献
Ada(R) is a registered trademark of the U.S. Government, Ada Joint Program Office. 相似文献
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Two series of molybdena catalysts supported on a copper treated fumed silica were prepared and their properties for the selective oxidation of methane to formaldehyde were compared with the copper free analogs. The catalysts were tested at ambient pressure in a fixed bed microreactor using a 5:1 CH4:N2O mixture in the temperature range 500–600C. In a second series of tests the propensity of silica and alumina supports to catalyse the decomposition of formaldehyde was assessed. The copper free catalysts lost their selectivity to formaldehyde when the MoO3 loading exceeded 5wt% but loadings up to 15wt% were possible with two copper treated supports without loss of selectivity. Yield of formaldehyde was superior over the copper treated catalysts also. This improved performance was associated with the ability of metallic copper to act as a co-catalyst and increasing the lability of the lattice oxygen in the supported molybdena phase. On all catalysts combustion of formaldehyde in the catalytic reactor occurred and the second series of tests showed that this combustion could occur also on the support material. 相似文献
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J. E. Macías-Sámano J. H. Borden H. D. Pierce Jr. R. Gries G. Gries 《Journal of chemical ecology》1997,23(5):1333-1347
In laboratory bioassay experiments, the beetles Pityokteines elegans were attracted to volatiles captured from bolts of grand fir, Abies grandis, colonized by P. elegans males. Male-specific volatiles detected by coupled gas chromatographic–electroantennographic detection (GC-EAD) analysis and by GC–mass spectrometry employing a chiral column were: (S)-(?)-ipsenol, (+)- and (?)-ipsdienol, and ipsenone. Field experiments demonstrated that 1:1 combinations of (?)-ipsenol and (±)-ipsdienol strongly attracted insects of both sexes to multiple-funnel traps. No beetles were attracted to any of these compounds alone, and both enantiomers of ipsdienol were required with (?)-ipsenol to induce attraction. Ipsenol and ipsdienol are now reported as pheromones of five Pityokteines species. Specificity of semiochemical-based communication between sympatric P. elegans and P. minutus appears to be based on host preference and on the composition and chirality of the pheromone blend. 相似文献
117.
Cooling schemes for longitudinally diode laser-pumped Nd:YAG rods 总被引:21,自引:0,他引:21
Weber R. Neuenschwander B. Mac Donald M. Roos M.B. Weber H.P. 《Quantum Electronics, IEEE Journal of》1998,34(6):1046-1053
Longitudinal diode laser pumping causes pronounced inhomogeneous heating of the laser material. The effect of the thermal load on the mechanical and optical properties is significantly influenced by the method used for cooling the pumped surface. Four methods for longitudinally pumped Nd:YAG rods were compared experimentally and with finite-element (FE) analysis. The pumped surface exposed to air or to flowing water, a sapphire plate pressed onto the pumped surface and composite rods, having an undoped pumped end, were investigated. The comparison includes temperature and stress distributions with the emphasis on thermal lensing. Careful validation of the FE code with experiments allowed to numerically comparing the cooling methods under identical conditions 相似文献
118.
Eccles Jacquelynne S.; Midgley Carol; Wigfield Allan; Buchanan Christy Miller; Reuman David; Flanagan Constance; Mac Iver Douglas 《Canadian Metallurgical Quarterly》1993,48(2):90
Although most individuals pass through adolescence without excessively high levels of "storm and stress," many do experience difficulty. Why? Is there something unique about this developmental period that puts adolescents at risk for difficulty? This article focuses on this question and advances the hypothesis that some of the negative psychological changes associated with adolescent development result from a mismatch between the needs of developing adolescents and the opportunities afforded them by their social environments. It provides examples of how this mismatch develops in the school and in the home and how it is linked to negative age-related changes in early adolescents' motivation and self-perceptions. Ways in which more developmentally appropriate social environments can be created are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
119.
B Bazán-Perkins V Carbajal B Sommer M Macías-Silva M Gonzalez-Martinez F Valenzuela EE Daniel LM Monta?o 《Canadian Metallurgical Quarterly》1998,358(5):567-573
OBJECTIVES: To: (1) develop a pharmaceutical care multicenter outcomes research project using clinical pharmacy residents and preceptors; (2) develop two research protocols to document pharmacists' impact on clinical, economic, and humanistic outcomes of therapy; (3) develop and implement a data collection process and methodology for outcomes research; (4) evaluate the effectiveness of the multicenter outcomes research process; and (5) prepare clinical pharmacy preceptors and residents to conduct outcomes research. DESIGN AND SETTING: Two research protocols were developed, each a randomized, parallel, open-label evaluation of patients at 10 Department of Veterans Affairs and 1 university medical center. One protocol focused on patients with chronic obstructive pulmonary disease (COPD) and the other on patients with hypertension. The study evaluated pharmacists' management of these two patient groups. PATIENTS AND OTHER PARTICIPANTS: 133 patients with hypertension and 98 patients with COPD; 33 pharmacy directors and preceptors; 45 pharmacy residents. MAIN OUTCOME MEASURES: Clinical, economic, and humanistic outcomes of pharmacists' interventions. The processes of developing a multicenter outcomes study were evaluated, including the data collection process. RESULTS: The two study protocols and an educational program for study participants were developed. A data collection process was developed and implemented, with the paper process being successful and the computer data collection process not implemented due to time constraints. Overall, the multicenter outcomes research process was successful. CONCLUSION: The study provides a framework of processes and sites for the future development of other outcomes research studies. Clinical, economic, and humanistic outcomes are reported in Parts 2 and 3. 相似文献
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