6,373 research outputs found
Modelling delay and noise in arbitrarily coupled RC trees.
No full textClosed-form equations for second-order transfer functions of general arbitrarily coupled resistance-capacitance (RC) trees with multiple drivers are reported. The models allow precise delay and noise calculations for systems of coupled interconnects with guaranteed stability and represent the minimum complexity associated with this class of circuits. Their accuracy is extensively compared against other relevant models and is found to be better or comparable to more expensive models. All results are derived from a theoretical approach, and their physical basis is examined. The simplicity, accuracy, and generality of the models make them suitable for use in early signal integrity analyses of complex systems and incremental physical optimization
openforcefield/openff-forcefields: Version 2.0.0-rc.1 "Sage" Release Candidate
No full textThe contents of this major release candidate are adapted from https://github.com/openforcefield/openff-sage/releases/tag/2.0.0-rc.1. See that release's notes and assets for more details.
Provided that early use of this force field shows no major deficiencies, this may be promoted to the full Sage release
A Compact 10-MHz RC Frequency Reference With a Versatile Temperature Compensation Scheme
No full textThis article presents the design and implementation of a compact CMOS RC frequency reference. It consists of a frequency-locked loop (FLL) that locks the period of a voltage-controlled oscillator (VCO) to the time an RC network takes to charge to a reference voltage. Conventionally, an RC time constant with a near-zero temperature coefficient (TC) is realized by using a trimmed network of resistors with different TCs. In this work, such a network is used to realize a temperature-dependent reference voltage whose TC cancels that of a single-resistor RC time constant. Compared with the conventional approach, which requires resistors with TCs of opposite polarity, the proposed approach can be implemented with resistors with TCs of similar polarity, and so it can be implemented in most CMOS processes. To compensate for RC spread, a trimmed capacitor is used to adjust the nominal frequency. Two prototype chips were made, one based on p- /n-polysilicon resistors and other based on silicided/p-diffusion resistors. Fabricated in a standard 180-nm CMOS technology, the polysilicon-based prototype has an active area of 0.01 mm2 and an absolute inaccuracy of ±2800 ppm from -45 °C to 125 °C with a fixed TC-trim and a one-point frequency trim. After one week of accelerated aging at 150 °C, however, significant drift (5000 ppm) was observed. The diffusion-based prototype exhibits greater inaccuracy (±14 400 ppm) but much less drift (600 ppm).Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Electronic InstrumentationMicroelectronic
Giardia assemblage A: human genotype in muskoxen in the Canadian Arctic
No full textAs part of an ongoing program assessing the biodiversity and impacts of parasites in Arctic ungulates we examined 72 fecal samples from muskoxen on Banks Island, Northwest Territories, Canada for Giardia and Cryptosporidium. Cryptosporidium spp. were not detected, but 21% of the samples were positive for Giardia. Sequencing of four isolates of Giardia demonstrated G. duodenalis, Assemblage A, a zoonotic genotyp
A CMOS Dual-RC frequency reference with ±250ppm inaccuracy from -45°C to 85°C
No full textTo comply with wired communication standards such as USB, SATA and PCI/PCI-E, systems-on-chip require frequency references with better than 300ppm accuracy. LC-based references achieve 100ppm accuracy [1], but suffer from high power consumption (∼20mW). Thermal diffusivity (TD) references require less power (∼2mW), at the expense of less accuracy (1000ppm) [2]. RC-based references offer the lowest power consumption, but their accuracy is typically limited to ∼0.1% [3]. In RC relaxation oscillators, comparator offset and delay are the major sources of inaccuracy [4,5]. References based on frequency-locked loops (FLLs) circumvent these by locking an oscillator's frequency to the time-constant of an RC filter, but their accuracy is then limited by the nonlinear temperature dependency of on-chip resistors [3,6].Session 3.3 Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Electronic Instrumentation(OLD)Applied Quantum ArchitecturesMicroelectronic
Short-term alteration in voluntary feed intake after selenium supplementation in Angora goat kids
No full textThe objective of this study was to examine the effect of selenium (Se) supplementation on voluntary feed intake in Se-deficient Angora goat kids and its temporal relationship to alterations in the concentrations of thyroid hormones in plasma and the activity of glutathione peroxidase in serum. Angora goat kids were fed pelleted lucerne with a Se concentration of 20 mu g/kg of dry matter (DM) and treated orally with either Se (0.1 mg/kg of liveweight weekly, as sodium selenate) or deionised water. Supplementation with Se had no effect on DM intake measured over 21 days. Serum activity of glutathione peroxidase was increased by Day 1 of treatment (P < 0.001), plasma concentration of thyroxine was decreased by Day 21 of treatment (P < 0.01), and plasma concentration of triiodothyronine was unaffected by treatment. It is concluded that increased appetite is unlikely to be the primary mechanism involved in the response to Se supplementation in Angora goats.PT: J; CR: *SAS I INC, 1988, SAS US GUID STAT VER ARTHUR JR, 1993, AM J CLIN NUTR S, V57, P236 BUNK MJ, 1980, J NUTR, V110, P743 DONALD GE, 1993, AUST J EXP AGR ANIM, V33, P411 EWAN RC, 1976, J NUTR, V106, P702 HAFEMAN DG, 1974, J NUTR, V104, P580 HUSSEIN KSM, 1982, ACTA AGR SCAND, V23, P556 THOMPSON JN, 1969, J NUTR, V97, P335 THOMPSON KG, 1980, RES VET SCI, V28, P321 UNDERWOOD EJ, 1977, TRACE ELEMENTS HUMAN WALSH DM, 1993, INT J VITAM NUTR RES, V63, P188 WICHTEL JJ, 1995, IN PRESS J DAIRY SCI WICHTEL JJ, 1996, NEW ZEAL J AGR RES, V39, P111; NR: 13; TC: 1; J9: N Z J AGR RES; PG: 4; GA: UM341Source type: Electronic(1
Experimental and theoretical investigation of crack width calculation methods for RC ties
No full textThis paper theoretically and experimentally investigates the semi-empirical formulas recommended by Eurocode 2 (EC2), fib Model Code 2010 (MC2010), and Eurocode 2 with the German National Annex (DIN) for calculating crack widths in reinforced concrete. It is shown that the formulas can be derived from the principles for the idealized behavior of RC ties. However, instead of explicitly solving the resulting differential equations, the use of simplifications leads to inconsistent formulas. An experimental study was carried out involving the testing of eight RC ties to discover the modeling uncertainty of the formulas. It was found that EC2 substantially overestimated the crack widths for the RC ties. MC2010 and DIN seemed to predict the crack widths better, but gave rather a large number of nonconservative crack width predictions. These experimental results, combined with the theoretical study, suggest that a more consistent calculation model should be formulated by explicitly solving the resulting differential equation.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Applied Mechanic
Youth living with anxiety: A study focusing on treatment options including medical cannabis
No full textMedical cannabis (MC) is gaining recognition as a treatment option in healthcare and yet, it still lags behind in the area of mental health. This inquiry examines the lived experience of people aged 18 to 25, living with anxiety, with an objective of examining their attitude towards MC as a treatment option for anxiety. The inquiry extends further to examine the participants understanding of MC and their concerns about accessing it is a treatment for anxiety. A link to an electronic survey consisting of 22 questions was posted on social media. The 135 responses received indicated that there is significant interest in MC as a treatment option for anxiety. The greatest barriers experienced by participants were side effect concerns that related more directly to recreational cannabis (RC) and stigma related more directly to RC. The results indicate that there is a lack of understanding and education regarding the differences between MC and RC. Based on the results of this survey, it is recommended that the general public, including healthcare professionals, need extensive education on the possible benefits and risks of MC and how they differ from RC.Medical cannabisanxietytreatmen
RC SMOOTHING OF SPECTRA
No full textAuthor Institution: Department of Physics, Michigan State University East LansingBy convoluting an exponential function with calculated spectra consisting of single and multiple sets of lines of various widths and line shapes, we have determined the effects that time constant (RC) has on recorded spectra. For equivalent experiments, in which the scanning rates d/dt are equal, we have concluded that the optimum value of RC is essentially independent of whether the spectrum is to be digitized or not, and independent of the sampling rate if digitization is used. A trade-off among the desirable and undesirable effects of RC leads us to recommend a value of RC about one-tenth of the full width at half height of the sharpest individual lines in the observed spectrum. This research was supported by a grant from the National Science Foundation
Hypopituitarism in childhood and adolescence following traumatic brain injury: the case for prospective endocrine investigation.
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