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991.
MP Rosen 《Canadian Metallurgical Quarterly》1999,6(1):72-4; discussion 74-5
992.
Steve Yeung James Lee Berry Lam Jonathan Ng Ivan Tsoi 《Journal of the Society for Information Display》2000,8(4):283-288
A new driving scheme for liquid‐crystal displays has been proposed, which uses paraunitary matrices as the diagonal building blocks. The new driving scheme has the advantages of lower hardware complexity than the well‐known MLA. In this paper, a new method is proposed for the implementation of gray scale in the recently proposed paraunitary driving scheme and the MLA. The method is based on multi‐order paraunitary/orthogonal building blocks, which strikes a balance between frame size and number of voltage levels. 相似文献
993.
994.
The purpose of the present paper is to investigate the effect of elastic deformation of bearing liner on the acoustic behavior of oil lubricated journal bearings.Analysis is performed for hydrodynamic(HD) and elasto-hydrodynamic (EHD) lubrications.Dynamic behavior and acoustical properties are investigated through an analysis of pressure fluctuation calculated from the Reynolds equation governing the flow in the clearance space of the journal bearing.This is solved numerically using the finite difference method with the successive over relaxation technique.In elasto-hydrodynamic lubrication,the finite element method with in iteration scheme is adopted to solve both Reynolds equation and the three-dimensional elasticity equation representing the displacement field in the bearing shell.The results show that the sound pressure level of the bearing is markedly influenced by the flexibility of the bearing liner,the viscosity of lubricant and the load applied to journal.HD analysis shows that the journal centre’s orbit,from a disturbed position,converges to the static equilibrium position faster than EHD lubrication.The results of the present paper could aid in the design of low-noise rotor-bearing systems supported by oil lubricated journal bearings. 相似文献
995.
996.
S von Greyerz MP Zanni K Frutig B Schnyder C Burkhart WJ Pichler 《Canadian Metallurgical Quarterly》1999,162(1):595-602
Drugs like sulfamethoxazole (SMX) or lidocaine can be presented to specific human alphabeta+ T cell clones (TCC) by undergoing a noncovalent association with MHC-peptide complexes on HLA-matched APCs. For a better understanding of the molecular basis of the recognition of such drugs by specific TCC, we investigated 1) the fine specificity of the recognizing TCR, 2) the dose-response relationship for the induction of proliferation or cytokine production, and 3) the mechanism of TCR triggering. For that purpose, we tested the reactivity of 11 SMX-specific CD4+ TCC and 2 SMX-specific CD8+ TCC to a panel of 13 different sulfonamide derivatives bearing the same core structure. Five of 13 clones recognized only SMX, while all other clones were responding to as many as 6 different compounds. Some of the compounds needed up to two orders of magnitude higher concentrations than SMX to stimulate TCC, thereby displaying features of weak agonists. Different clones showed clear differences in the minimal drug concentration required for the induction of a proliferative response. Therefore, weaker or stronger agonistic properties were not a characteristic of a given sulfonamide derivative but rather an intrinsic property of the reacting TCR. Finally, the number of down-regulated TCRs was a logarithmic function of the ligand concentration, implicating that specific T cells were activated by serial TCR engagement. Our data demonstrate that, despite the special way of presentation, nonpeptide Ag like drugs appear to interact with the TCR of specific T cells in a similar way as peptide Ags. 相似文献
997.
Berry P.A.M. Freeman J.A. Rogers C. Benveniste J. 《Geoscience and Remote Sensing, IEEE Transactions on》2007,45(9):2869-2874
The Envisat RA-2 burst echoes are being gathered throughout the mission; however, these data are only now being made generally available by the European space agency. Considerable work has been necessary to turn these engineering-level data into a useable altimeter product. This paper documents the processing steps undertaken to generate usable data and presents the first extensive analysis of this unique dataset, using over 75 000 burst sequences with a global distribution. The results show that the burst echo data from Envisat are of extremely low noise, which is particularly evident over non-ocean surfaces, and contain a wealth of detailed information from both land and ocean surfaces. Examples illustrate the complexity of surface response from targets such as inland water and rough terrain. These unique data clearly have the potential to inform future instrument design as well as to improve the understanding of existing altimeter datasets. 相似文献
998.
999.
Blascovich Jim; Mendes Wendy Berry; Hunter Sarah B.; Salomon Kristen 《Canadian Metallurgical Quarterly》1999,77(1):68
The authors conducted an experiment to test a theoretical explanation of social facilitation based on the biopsychosocial model of challenge and threat. Participants mastered 1 of 2 tasks and subsequently performed either the mastered (i.e., well-learned) or the unlearned task either alone or with an audience while cardiovascular responses were recorded. Cardiovascular responses of participants performing a well-learned task in the presence of others fit the challenge pattern (i.e., increased cardiac response and decreased vascular resistance), whereas cardiovascular responses of participants performing an unlearned task in the presence of others fit the threat pattern (i.e., increased cardiac response and increased vascular resistance), confirming the authors' hypotheses and the applicability of the biopsychosocial model of challenge and threat to explain these results. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
Berry J Heimbecher S Hart JL Sequeira J 《Drug development and industrial pharmacy》2003,29(8):865-876
Presented in this work are the results of a study designed to investigate the impact of the valve metering chamber volume and actuator design on the aerodynamic particle size distribution (PSD) of a suspension metered dose inhaler (MDI) containing propellant HFA-227. It was hypothesized that the valve metering volume and the actuator design in the MDI could influence the PSD of the emitted dose since it would affect the aerosol spray dynamics. The PSD results from this study, measured using cascade impaction, revealed that samples containing an actuator intended for oral delivery (rectangular mouthpiece and orifice diameter of ≈0.5 mm) produced a higher fine particle dose (FPD) than those containing an actuator intended for nasal delivery (circular nosetip and orifice diameter of ≈1 mm). In addition, the drug PSD profile was shown to be more sensitive to differences in the particle size of the suspended material when the oral actuator was used compared to when the nasal actuator was used. The valve metering chamber (25 vs. 63 μL volume) did not appear to have a major effect on the product aerodynamic PSD or the droplet size. These results demonstrate the importance of actuator design and orifice size in determining the aerodynamic PSD of an MDI. 相似文献