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1.
This is a follow‐up report on the end‐to‐end data link performance of the NASA deep space network. The focus of this report
is the effect of traffic loading on data delivery. Architecture of the existing network is modeled via COMNET. The contribution
of the data latency to the overall acquisition time is simulated as a function of network traffic conditions. The results
show steady‐state latencies in the range of tenths of milli‐seconds under a mild loading condition. During heavy traffic,
a delay rate of over a hundred seconds of increased delay per hour of network operation time is observed. This is primarily
due to the queueing delays associated with large volume of data stored in the buffers throughout the link.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
2.
The possibilities of using monascus to colour gels were studied by comparing it with cochineal. Gels were prepared with four gelling agents—carrageenan, gellan, gelatine and xanthan—and their colour was measured with a Hunter Lab colorimeter. The equations relating L* and h with the concentrations of sugar [SU] and colorant [COL] were deduced, and it was found that [COL] had more influence on colour than [SU]. In general, for these four gelling agents the colour of monascus gels is orange-red and the colour of cochineal gels is purplish red. The gels made with xanthan were always the lightest, whether they were made with cochineal or with monascus. 相似文献
3.
Kunkel Mark A.; Hector Mark A.; Góngora Coronado Elías; Castillo Vales Victor 《Canadian Metallurgical Quarterly》1989,36(3):322
Conducted a study of client expectations of psychological services in Yucatán, Mexico, under the sponsorship of a grant from the Organization of American States. The Expectations about Counseling–Brief form (EAC-B) questionnaire was translated and administered to 488 subjects across age, sex, and experience with psychological services. Subsequent analyses supported the reliability and robustness of the Spanish EAC-B, with factor structure similar to the EAC-B in English. Some relation was found among age, sex, prior counseling experience, and expectations about counseling. Implications of these data for future research and comparison with U.S. subjects are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
M A M Maqueda Sergio A Martinez D Narváez Miriam G Rodriguez Ricardo Aguilar Victor M Herrero 《Water science and technology》2006,53(11):135-142
The Mexican petrochemical industry, Morelos S.A. de C.V., is one of the biggest and more important petroleum industries in Mexico and Latin America. It has an activated sludge system to treat its wastewater flow, which is approximately 7,000 m3/d. The wastewater contains volatile organic carbon substances classified as toxics. The old surface aeration system was changed for fine bubble diffusers; however, one major drawback of the new aeration system is that the temperature in the bioreactor has increased due to the compression of the air, which at the compressor exit reaches 85 degrees C. This effect results in the temperature in the bioreactor attaining 32 degrees C during the fall, whereas in the spring and summer, the bioreactor temperature reaches higher values than 40 degrees C. The high temperatures reduce the microorganism activity and cause a higher volatilisation rate of volatile compounds, among other effects, which affect the performance of the biological treatment. This work was performed to obtain a better modelling of the wastewater treatment from the petrochemical industry. The model describes the effect of the temperature on the performance of the biological treatment. The model was obtained from tests that were carried out in laboratory reactors with 14 L capacity, which were operated at different temperatures (from 30 to 45 degrees C), with the same wastewater and conditions as the actual system. 相似文献
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6.
Joaquín Cortés Eliana Valencia Gonzalo Aguila Esteban Orellana Paulo Araya 《Catalysis Letters》2008,126(1-2):63-71
An experimental study is made of the time decay of activity of the CO–NO reaction on a Pd/Al2O3 looking at the effect on reaction order and apparent activation energy. The optimum kinetics parameters fitting the steady state data at moderate pressures are determined. The time decay curves are analyzed through various catalyst deactivation models. 相似文献
7.
Garey A. Fox John W. Fuchs Victor F. Medina Kaumudi Atapattu 《Canadian Metallurgical Quarterly》2007,133(3):255-262
Recent research has proposed the use of asphalt and tall-oil-pitch emulsions for stabilizing radioactive contamination deposited on surfaces in urban areas. The objective of this project was to investigate whether surface applied emulsions could capture airborne radioactive particulate. Laboratory experiments included wind-blown particulate capture studies using an acrylic column and particulate retainment experiments using a wind box capable of producing wind speeds of 96?km/h. A probe methodology was developed to relate particulate retainment to a tack force on the emulsion surface. Experiments were also performed to determine the potential for such emulsions to absorb particulate matter into their emulsion matrix. Tall-oil-pitch emulsions outperformed asphalt emulsions in terms of particulate retention, tack force, and the ability to absorb magnesium silicate. Both tall-oil-pitch and asphalt emulsions were capable of extracting 22–24?g?m?2 of powder from particulate-laden airflow. Tall-oil-pitch emulsions were capable of retaining as much as 5–10% of magnesium silicate powder applied (i.e., retainment densities of 10–20?g?m?2) even after seven?days of curing and after applying 96.5?km/h (60?mph) wind. Tall-oil-pitch emulsions were able to absorb surface-applied magnesium silicate (approximately 0.1–0.2?g of magnesium silicate per 1.0?g of emulsion within three?days) into their emulsion matrix, preventing the magnesium silicate from being exposed to the external environment. Initial results with these five different emulsion formulations suggested particulate capture was feasible. Future emulsion formulations (i.e., longer curing times with greater acid concentrations) should be tested to optimize this postdetonation response strategy. 相似文献
8.
9.
Ana Cuesta Amelia Martí nez-Alonso Juan M. D. Tasc n 《Fullerenes, Nanotubes and Carbon Nanostructures》1997,5(5):1075-1081
Fullerene reactivity in an oxygen plasma was measured and compared with those determined under the same conditions for a comprehensive set of 50 carbon materials. The possible reasons for the high plasma reactivity of the fullerene sample in an oxygen plasma are discussed. 相似文献