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1.
A new hybrid automatic repeat request scheme employing packet combining based on the Viterbi decoder is presented. It is shown that the proposed form of combining, together with a rearrangement of the signal constellation, can outperform similar forms of packet combining such as average diversity combining 相似文献
2.
Schmitt Neal; Gleason Sandra E.; Pigozzi Bruce; Marcus Philip M. 《Canadian Metallurgical Quarterly》1987,72(4):622
A total of 438 manufacturing firms reported their business relocation activity, their overall attitude toward the business climate in Michigan, and their assessment of 34 business climate dimensions. Using a lens model paradigm, we explored reasons for a lack of relation between actual relocation decisions and overall business climate attitudes. Location decisions were most highly correlated with distance and labor considerations, whereas overall business climate was most highly correlated with tax considerations, and secondarily correlated with labor problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
3.
Heinz Blenke Beate Farys-Kahle Carl-Max Freiherr Von Meysenbug Helmut Weimer 《化学,工程师,技术》1985,57(5):381-390
Rationalizing drawings for chemical apparatus . For small and medium-sized manufacturers of apparatus, producing drawings may constitute a disproportionate waste of time and personnel, particularly when no new designs are involved but only modification or improvement of drawings supplied by the customer. One possibility for rationalizing drawing is to simplify the old-fashioned approach by using symbols for frequently drawn or standard items, or by listing alphanumerically. This presumes a kind of systematization permitting determination of those symbols and their reasonable use, as well facilitating rationalization by means of data processing. There are different approaches to computer-aided drawing (from computer controlled drawing-board to interactive screens); here a CAD programme is presented which was especially developed for graphic presentation of chemical apparatus, and which can be used without learning a programming language. 相似文献
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Schmitt Neal; Oswald Fred L.; Kim Brian H.; Gillespie Michael A.; Ramsay Lauren J.; Yoo Tae-Yong 《Canadian Metallurgical Quarterly》2003,88(6):979
The current study investigated the impact of requiring respondents to elaborate on their answers to a biodata measure on mean scores, the validity of the biodata item composites, subgroup mean differences, and correlations with social desirability. Results of this study indicate that elaborated responses result in scores that are much lower than nonelaborated responses to the same items by an independent sample. Despite the lower mean score on elaborated items, it does not appear that elaboration affects the size of the correlation between social desirability and responses to biodata items or that it affects criterion-related validity or subgroup mean differences in a practically significant way. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Peter Horn Peter Schaaf Brigitte Holbach Stefan Hölzl Heinz Eschnauer 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1993,196(5):407-409
For provenance assignments of wines strontium isotope ratios can be used because soils from different wine-growing regions, and hence the wines grown there, each show specific ratios. Some successful applications are demonstrated.
87Sr/86Sr aus Gestein und Boden in Rebe und Wein
Zusammenfassung Zur Herkunftsbestimmung von Weinen können Strontium-Isotopenverhältnisse herangezogen werden, da die Böden verschiedener Weinbaugebiete, und damit die dort gezogenen Weine, jeweils spezifische Verhältnisse aufweisen. Einige erfolgreiche Anwendungen werden demonstriert.相似文献
7.
J Abart K Eberhardt H Fischer W Huk E Richter F Schmitt T Storch B Tomandl E Zeitler 《Canadian Metallurgical Quarterly》1997,21(4):532-538
PURPOSE: A study was performed to assess the stimulation threshold for healthy adults using sinusoidally oscillating gradients. METHOD: One hundred thirteen healthy adults were examined in the study. ECG and physiological parameters were measured. All measurements were performed of both the head and the abdomen. The subjects were measured in the supine position with the region of interest positioned in the center of the gradient coils. The measurement was performed for three orthogonal, four oblique, and double oblique orientations. RESULTS: No volunteer reported painful, severe stimulation. The mean thresholds for peripheral stimulation in head and body measurement were similar: 85.5% of stimulation during examination of the head and 87.6% during measurements of the abdomen were reported when the y-gradient was used. CONCLUSION: The greatest frequency of reported stimulations occurs when the y-gradient is used. This was confirmed by the results and supports the hypothesis that orthogonal to the y-axis the body has its largest conductive loop, resulting in the strongest peripheral stimulation. 相似文献
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9.
Metrology of freeform shaped parts 总被引:2,自引:0,他引:2
The scope of this keynote paper is to present the state of the art in the metrology of freeform shapes with focus on the freeform capabilities of the most important measuring techniques and on related metrological issues. Some examples of products are presented, for which the metrology of freeform shapes is important to guarantee the desired functional performance of the product. A classification of freeform measuring tasks and the corresponding metrological requirements are presented. A review of the most important measuring techniques is presented along with their capabilities for freeform measuring tasks. Specification and verification of freeform surfaces, including data evaluation and comparison to specifications are discussed, along with the measurement uncertainty and traceability of freeform measurements. 相似文献
10.