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991.
The matrix pencil (MP) method, based on the singular value decomposition (SVD), is applied to quantitative NMR spectroscopy. Its relationship to other SVD-based methods is also presented. Simulations and applications are given to demonstrate the capability of superior performance.©1993 John Wiley & Sons Inc  相似文献   
992.
Institute of Rock Mechanics, Academy of Sciences of the USSR, Moscow. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 1, pp. 39–44, January-February, 1992.  相似文献   
993.
994.
A trajectory problem of pursuit and evasion on a plane is considered for the case of equal absolute velocities of the players. Exact solutions are obtained for fixed initial conditions.Translated from Kibernetika i Sistemnyi Analiz, No. 3, pp. 138–143, May–June, 1992.  相似文献   
995.
A family of converters for UPS production burn-in energy recovery   总被引:2,自引:0,他引:2  
This paper introduces a family of power converters for power recycling during the burn-in test of synchronized uninterruptible power supplies (UPSs) with sinusoidal output voltage. The use of the power recycler to replace the resistor load bank in the UPSs burn-in test causes great energy savings, and the optimized use of electrical energy contributes in reducing the final cost of the product. The main feature of the new circuits is their ability to draw from the UPS and to inject into the utility-grid currents with low total harmonic distortion (THD) and high power factor (PF). The new circuits operate at constant frequency and are regulated by conventional pulse width modulation (PWM) using dedicated PWM and PF controller integrated circuits developed for power supplies. Circuit operation, mathematical analysis, design example, and experimental results for discontinuous current mode (DCM) and continuous current mode (CCM) operation are provided in this paper  相似文献   
996.
Myofibroblasts that express alpha-smooth muscle actin (alpha-SMA) are detected in many chronic inflammatory diseases. Transforming growth factor-beta (TGF-beta) is a potent inducer of myofibroblast accumulation in tissues. In this study, scattered myofibroblasts and TGF-beta were quantified and localized in nasal polyps (NPs) and normal nasal mucosa (NM). NPs were sampled in 16 patients during ethmoidectomy and NM was obtained from 10 control subjects during rhinoplasty. alpha-SMA and TGF-beta were detected using immunohistochemistry and the numbers of labeled cells were quantified (alpha-SMA and TGF-beta indices) and compared between NPs and NM. In eight NPs, in which the pedicle was preserved, alpha-SMA and TGF-beta were evaluated and compared in the pedicle, central, and tip areas. Finally, TGF-beta expression was compared between low (zone 1), moderate (zone 2), and high (zone 3) zones of alpha-SMA positivity. alpha-SMA and TGF-beta indices were significantly higher in NPs than in NM. In the eight selected NPs, alpha-SMA-positive cells were significantly more abundant in the pedicle than in the central and tip areas, whereas TGF-beta-positive cells were significantly more numerous in the pedicle than in the tip area. The number of TGF-beta-positive cells was significantly higher in zone 3 than in zone 1 of alpha-SMA positivity. Myofibroblasts, which are abundant in NPs but rare in NM, could be involved in the growth of NPs by inducing extracellular matrix accumulation. The local development of myofibroblasts in NPs could be controlled by TGF-beta, locally produced by inflammatory cells.  相似文献   
997.
998.
Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 4, pp. 32–33, April, 1991.  相似文献   
999.
1000.
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