7,685 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
PROJECTIVE MULTIGRID FOR WILSON FERMIONS
No full textWe propose a multi-level algorithm for Wilson fermions in a background gauge field by the application of the projective multigrid method. A variational wave function is placed on blocks of 2d sites which gives an effective Dirac equation for coarser lattices with new effective gauge links. Renormalization group arguments are given to motivate our Ansatz. Finally we test the multi-level algorithm on a 2d U(1) lattice gauge theory and show that critical slowing down is eliminated for distances less than the confinement scale l-sigma defined by the string tension. As the quark mass vanishes convergence is accelerated by a factor of this length l-sigma measured in lattice units
Monogenic low renin hypertension
No full textMonogenic forms of low renin hypertension can now be identified in a large and heterogeneous family of hypertensive patients with highly specific etiologies and similar clinical manifestations. These include the following well-characterized disorders: apparent mineralocorticoid excess, Liddle's Syndrome, steroid 11beta-hydroxylase (11beta-OHD) and steroid 17-hydroxylase (17-OHD) deficiencies, glucocorticoid-remediable hyperaldosteronism (familial hyperaldosteronism type I), familial hyperaldosteronism type II, hypertension exacerbated by pregnancy and primary hyperaldosteronism (Conn's syndrome). The successful elucidation of specific DNA mutations in most of these conditions has emphasized the role of molecular genetics in hypertension, a field in which diagnosis can now be made on proven genetic evidence. The current knowledge of these genetic markers enables practitioners to make precise diagnoses, and to initiate specific therapy, in patients with these relatively uncommon but interesting and often treatable forms of hypertension
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
Electromyographic activity of the serratus anterior muscle in anterior glenohumeral instability pre and post surgical stabilisation
No full textFacilitating learning and retention of practical motor skills in a neuromusculoskeletal physiotherapy module
No full textA 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
Predicting Religious Doubt and Psychological Well-being Using Religious Orientation, Religious Coping, Prosperity Gospel Orientation, and Life Stress
No full textSubjective measures of psychological well-being (PWB) such as life satisfaction (LS) and positive affectivity (PA) have been related to religious orientation (RO), religious coping (RC), religious doubt (RD), and stressful life events (Stress). A recent construct, prosperity gospel beliefs (PGB), posits that God rewards the faithful with health and financial success. A PGB scale has been created and shown to have relationships with RO, prayer, attachment to God, materialism, and greed. This study explores how PGB predicts RD and PWB beyond RO, RC, and Stress. Participants (n = 79, Mage = 19.51; 74.7% female; 100% Christian) were recruited from psychology courses and completed questionnaires online, with procedures approved by the Lipscomb University IRB. Multiple linear regression analyses using forward selection were conducted with RD, LS, PA, and NA as dependent variables, and intrinsic RO, extrinsic RO, Quest RO, positive RC, negative RC, RD (for PWB variables only), PGB, and Stress as predictors. The regression for RD was significant, revealing that RD was best predicted by quest and extrinsic RO and negative RC (F(3, 75) = 13.06, R2 = 0.34). LS was best predicted by intrinsic RO and PGB (F(2, 76) = 13.07, R2 = 0.26). PA was predicted solely by intrinsic RO (F(1, 77) = 14.18, R2 = 0.16). NA was predicted by intrinsic RO and positive RC (F(2, 76) = 6.73, R2 = 0.15). These findings align with current literature, with the novel finding that PGB contributes to predicting LS
PROJECTIVE MULTIGRID METHOD FOR PROPAGATORS IN LATTICE GAUGE-THEORY
No full textA projective multigrid method is considered for application to fermion propagators in the presence of gauge fields. The collective variables on each block are defined by the gauge-invariant projection onto the lowest eigenstate for the block. The scheme is formulated in detail for two-dimensional bosons and Wilson fermions in the U(1) gauge theory and numerical studies are presented for bosons to demonstrate its potential for more efficient convergence. For example, at a confinement length of 8 lattice units on a 64 x 64 lattice, the projective multigrid method gives a speed up of almost two orders of magnitude relative to the Gauss-Seidel algorithm
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
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