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排序方式: 共有221条查询结果,搜索用时 15 毫秒
61.
Tal Vitaly Zlotnikov Ofir Degani Igor Brouk Yael Nemirovsky 《Microelectronics Journal》2011,42(10):1143-1150
We present analysis, optimization, design and characterization of an integrated passive analog phase shifter at 24 GHz in a commercially available 45 nm RF-CMOS process. The design is based on a well-known RC bridge topology, which was optimized for maximum phase shift and minimal amplitude response variation versus phase and frequency. Phase is controlled by varying DC voltage on a varactor, resulting in 60° maximum phase shift with 0.1 dB amplitude variation at 24 GHz. The size of the phase shifter circuit excluding pads and input/output buffers is 40×50 μm2. 相似文献
62.
63.
Whisman Mark A.; Uebelacker Lisa A.; Tolejko Natalie; Chatav Yael; McKelvie Margaret 《Canadian Metallurgical Quarterly》2006,21(3):626
The associations between marital discord and multiple measures of well-being (depression, anxiety, life satisfaction, and self-esteem) were evaluated in a population-based sample of 416 couples in which the husband was 65 years or older. Results indicated that greater marital discord was associated with greater depression and lower life satisfaction and self-esteem. Furthermore, the associations between marital discord and well-being remained significant when statistically controlling for the rival explanation of the Big Five personality traits. Finally, there was little evidence for gender differences in the magnitude of the associations between marital discord and well-being. Findings suggest that marital discord is an important correlate of multiple measures of well-being in older individuals and that this association is not confounded by the Big Five personality traits. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
64.
A three-dimensional statistical evaluation framework for performance measurement of robotic systems has been developed. A specific experimental setup has been designed, implemented, and evaluated for different robot characteristics (velocities and target location) and for a specific task. A statistical analysis method to evaluate performance is demonstrated. Results indicate the significance of this methodology since the capabilities and performance of a particular robot depend on actual operating conditions. 相似文献
65.
Aldridge Jan; Lamb Michael E.; Sternberg Kathleen J.; Orbach Yael; Esplin Phillip W.; Bowler Lynn 《Canadian Metallurgical Quarterly》2004,72(2):304
Ninety 4- to 13-year-old alleged victims of sexual abuse were interviewed by police officers using the National Institute of Child Health and Human Development (NICHD) investigative interview protocol, following which they were shown a human figure drawing and asked a series of questions. The drawing and associated questions elicited an average of 86 new forensically relevant details. They were especially productive with 4- to 7-year-olds, who provided an average of 95 additional details (27% of their total) after the drawing was introduced despite having previously "exhausted" their memories. Information elicited using the drawing may be less accurate, however, because recognition memory prompts predominated, so such drawings should only be introduced late in investigative interviews. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
66.
Yael Paran Swetlana A. Adansky-Boldin Raanan Margalit Hadassa Degani 《Israel journal of chemistry》2003,43(1-2):103-114
Diffusion MRI studies revealed specific morphological and physiological properties of MCF7 tumors implanted in the mammary gland of immunodeficient mice. These tumors mimic the histological and pathophysiological properties of human breast cancer in patients. The experiments were conducted by (1) applying varying diffusion gradient strengths, Gd, from 0 to 20 G/cm and a short diffusion time (td = 16 ms) in order to minimize the effect of restriction and exchange of water between the intra- and extracellular compartments, and (2) applying a strong constant gradient and diffusion times up to 96 ms, revealing water restriction and exchange. The normalized signal intensity was plotted against the diffusion weighting factor b , taking into account interaction with the imaging gradients. The curves were analyzed by applying a bi-exponential decay function assuming two exchanging water compartments, with fast and slow diffusion coefficients. The amplitudes and decay constants of the two exponents, a fast and a slow one, were related to the fraction and apparent diffusion coefficients of the extra- and intracellular water, respectively, considering contributions of restriction and exchange. During tumor progression the distribution of the diffusion parameters for the same experimental protocol varied and became less homogeneous. This was predominantly due to variations in the cellularity and increased necrosis. Upon treatment of the tumors with a new anti-estrogenic drug, tamoxifen methiodide, the changes in the diffusion parameters indicated increased cell swelling. Hence, this cytostatic response to treatment was detected before actual cell death was apparent. The potential capacity of diffusion MRI is of high clinical relevance and may help improve the noninvasive diagnosis and followup of treatment of this devastating disease. 相似文献
67.
Yael Miron 《Journal of hazardous materials》1980,3(4):301-321
Experimental thermal analysis and mass spectrometric results indicate that, when heated, monomethylamine nitrate dissociates to form monomethylamine anMonomethylamine, one of the dissociation products, is a flammable gas. In dry air, at room temperature, its lower limit of flammability is 4.9%. Its auPreventing acid build-up and rust formation is important for the safe handling and transport of monomethylamine nitrate. 相似文献
68.
Eli Aghion Yael Gueta Nir Moscovitch Boris Bronfin 《Journal of Materials Science》2008,43(14):4870-4875
A systematic study was carried out to evaluate the effect of up to 2.5% yttrium additions on the properties of Mg–3%Nd alloy
designated for high-temperature gravity casting applications. All the tested alloys were grain-refined by zirconium. The results
show that additions of yttrium significantly improved the tensile yield strength, fatigue strength, and creep resistance while
reducing the ductility. However, other properties such as the ultimate tensile strength and corrosion resistance in 5% NaCl
solution were nearly not affected. The strengthening effect obtained by the yttrium additions is explained in terms of solid-solution
strengthening and due to formation of a ternary phase of Mg–Nd–Y. The improved creep resistance was due to the large solubility
of yttrium in solid-solution magnesium matrix and to the effective creep deformation barriers created by the ternary phase.
The casting performance of the tested alloys in terms of fluidity was similar and no significant effect of the yttrium was
evident 相似文献
69.
UV disinfection of RBC-treated light greywater effluent: kinetics, survival and regrowth of selected microorganisms 总被引:2,自引:1,他引:1
The microbial quality of raw greywater was found to be much better than that of municipal wastewater, with 1.6 x 10(7)cfu ml(-1) heterotrophic plate count (HPC), and 3.8 x 10(4), 9.9 x 10(3), 3.3 x 10(3) and 4.6 x 10(0)cfu 100 ml(-1) faecal coliforms (FC), Staphylococcus aureus sp., Pseudomonas aeruginosa sp. and Clostridium perfringes sp., respectively. Further, three viral indicators monitored (somatic phage, host: Escherichia coli CN(13) and F-RNA phages, hosts: E. coli F+(amp), E. coli K12) were not present in raw greywater. The greywater was treated by an RBC followed by sedimentation. The treatment removed two orders of magnitude of all bacteria. UV disinfection kinetics, survival and regrowth of HPC, FC, P. aeruginosa sp. and S. aureus sp. were examined. At doses up to 69 mW s cm(-2) FC were found to be the most resistant bacteria, followed by HPC, P. aeruginosa sp. and S. aureus sp. (inactivation rate coefficients: 0.0687, 0.113, 0.129 and 0.201 cm2 mW(-1)s(-1), respectively). At higher doses (69-439 mW s cm(-2)) all but HPC (which exhibited a tailing curve) were completely eliminated. Microscopic examination showed that FC self-aggregate in the greywater effluent. This provides FC an advantage at low doses, since the concentration of suspended matter (that can provide shelter from UV radiation) in the effluent was very low. FC, P. aeruginosa sp. and S. aureus sp. did not exhibit regrowth up to 6h after exposure to increasing UV doses (19-439 mW s cm(-2)). HPC regrowth was proven to be statistically significant in un-disinfected effluent and after irradiation with high UV doses (147 and 439 mW s cm(-2)). At these doses regrowth resulted from growth of UV-resistant bacteria due to decreased competition with other bacteria eliminated by the irradiation. 相似文献
70.
Benny Y Manzanera S Prieto PM Ribak EN Artal P 《Journal of the Optical Society of America. A, Optics, image science, and vision》2007,24(6):1538-1544
The human eye is affected by large chromatic aberration. This may limit vision and makes it difficult to see fine retinal details in ophthalmoscopy. We designed and built a two-triplet system for correcting the average longitudinal chromatic aberration of the eye while keeping a reasonably wide field of view. Measurements in real eyes were conducted to examine the level and optical quality of the correction. We also performed some tests to evaluate the effect of the corrector on visual performance. 相似文献