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991.
A new phantom is described which simulates the human cardiac anatomy for applications in ultrasound imaging, ultrasound Doppler, and color-flow Doppler imaging. The phantom consists of a polymer left ventricle which includes a prosthetic mitral and aortic valve and is connected to a mock circulatory loop. Aerated tap water serves as a blood simulating fluid and ultrasound contrast medium within the circulatory loop. The left ventricle is housed in a Lexan ultrasound visualization chamber which includes ultrasound viewing ports and acoustic absorbers. A piston pump connected to the visualization chamber by a single port pumps degassed water within the chamber which in turn pumps the left ventricle. Real-time ultrasound images and Doppler studies measure flow patterns through the valves and within the left ventricle. 相似文献
992.
F. R. DEL VALLE H. VILLANUEVA J. REYES-GOVEA M. ESCOBEDO M. J. MUNOZ J. PONCE M. VEGA M. HERNANDEZ G. VELAZQUEZ 《Journal of food science》1985,50(2):551-552
A nitrogen balance study, comparing a low-cost soy-oats infant formula with and without supplemental methionine, was carried out with infants of ages 3 - 26 months at a single equivalent level of nitrogen intake (approximately 850 mg/kg/day). Nitrogen retention was found to be unaffected by methionine supplementation. Com- parison of data obtained in this study with previous research re- vealed that a critical value for intake of total L-sulfur amino acids apparently exists in infants 3 - 26 months of age, below which methionine supplementation will increase nitrogen retention, but above which it will not. This value appears to coincide with that of 49 mg/kg/day recommended for infants by the FNB. 相似文献
993.
994.
Saponara S. Fanucci L. Marsi S. Ramponi G. Kammler D. Witte E.M. 《Circuits and Systems II: Express Briefs, IEEE Transactions on》2007,54(7):596-600
This brief presents an application-specific instruction-set processor (ASIP) for real-time Retinex image and video filtering. Design optimizations are addressed at algorithmic and architectural levels, the latter including a dedicated memory structure, an adapted pipeline, bypasses, a custom address generator and special looping structures. Synthesized in CMOS technology, the ASIP stands for its better energy-flexibility tradeoff versus reference ASIC and digital signal processing Retinex implementations. 相似文献
995.
996.
Up to 30% of the released colour arising from bleached kraft pulp and paper production comes from the alkaline extraction stage. This waste stream can therefore be readily targeted to remove colour at source in mills where improved colour management is required. The efficacy of five advanced oxidative treatment and physico-chemical technologies in removing colour from a typical Eop stage effluent was compared. The most effective oxidative treatment was peroxymonosulphate (79% colour removal in 15 minutes). Ozone and TAML treatments removed 74% and 58% of colour respectively within 30 minutes. In comparison, hydrogen peroxide alone was only able to remove 35% of the colour over 4 hours. Coagulation with polyaluminium chloride achieved 89% colour removal within 5 minutes. However, this treatment produced an undesirable sludge, and may cause toxicity in the treated wastewater. Overall, colour removal ability of the five technologies ranked from highest to lowest was polyaluminium chloride > peroxymonosulfate > ozone > TAML > hydrogen peroxide. Other factors, such as operating costs, feedstock modification and capital infrastructure, also need to be taken into account when selecting the most suitable colour management option. 相似文献
997.
Ohne Zusammenfassung 相似文献
998.
Accurate assessment of the availability of solar energy at the Earth's surface is hampered by difficulties associated with the variability of solar radiation in space and time and with the angular position in the sky hemisphere. This paper assesses each of these problem areas by highlighting the difficulties and the attempts to offset them. Major emphasis is placed on extrapolation and interpolation procedures, the sensitivity of inclined surfaces to variations in the solar input, numerical models for calculating the irradiance of inclined surfaces and the time scales for which these computations are valid.Finally, the reader is urged to consider the significance of these difficulties in light of both radiation measurement errors and the sensitivity of the application to imprecise determinations of the radiation environment. 相似文献
999.
E. Gehri 《Holz als Roh- und Werkstoff》1985,43(3):83-88
Zusammenfassung Generell stellen die Verbindungsbereiche Schwachstellen dar. Zwar k?nnen in gewissen F?llen derartige Schwachstellen umgangen
werden. im Vordergrund steht jedoch eine gesicherte Erh?hung der Leistung bekannter Verbindungsarten. Voraussetzung hierfür
sind auf die jeweilige Verbindung (und Holzart) ausgerichtete konstruktive L?sungen. H?ufig lassen sich derartige Entwicklungen
nicht oder nur unvollst?ndig durch bereits normierte Regeln der Baukunde abdecken.
In general jointed areas are considered weak links. Although in certain cases these weak areas may be circumvented, it is
important to make efforts towards improving the performance of established joints. Constructive solutions adapted to specific
joints (and wood species) are one of the preconditions towards this am. Frequently this kind of development is merely insufficiently
or not at all covered by existing standardized regulations in construction technology.
Nach einem Vortrag des Verfassers auf der Dreil?nder-Holztagung 1984 in Augsburg 相似文献
High performance jointing techniques—State of art and development
Nach einem Vortrag des Verfassers auf der Dreil?nder-Holztagung 1984 in Augsburg 相似文献
1000.