Sökresultat

Filtyp

Din sökning på "*" gav 531335 sökträffar

Design and measurement of a CT delta-sigma ADC with switched-capacitor switched-resistor feedback

The performance of traditional continuous-time (CT) delta-sigma analog-to-digital converters (ADCs) is limited by their large sensitivity to feedback pulse-width variations caused by clock jitter in their feedback digital-to-analog converters (DACs). To mitigate that effect, we propose a modified switched-capacitor (SC) feedback DAC technique, with a variable switched series resistor (SR). The arc

Sources and properties of Amazonian aerosol particles

This review provides a comprehensive account of what is known presently about Amazonian aerosol particles and concludes by formulating outlook and priorities for further research. The review is organized to follow the life cycle of Amazonian aerosol particles. It begins with a discussion of the primary and secondary sources relevant to the Amazonian particle burden, followed by a presentation of t

Integration of a hand-reared chimpanzee (Pan troglodytes) infant into a social group of conspecifics

Abstract in UndeterminedRejections of infants among non-human primates occasionally occur in the wild as well as in captive settings. Controlled adoptions of orphans and introductions of individuals into new groups are therefore sometimes necessary in captivity. Consequently, behavioral research on integration procedures and on the acceptance of infants by adoptive mothers is much needed. In this

Heavy flavour physics in ALICE

With a centre-of-mass energy of 5.5 TeV per nucleon, Pb–Pb collisions at the LHC are expected to provide a copious yield of heavy quarks. In this paper, an overview of the ALICE perspectives for heavy flavour physics will be presented. The ALICE experiment will detect quarkonia both in the e+e− and in the μ+μ− decay channels. Open heavy flavoured hadrons will be studied in the semileptonic decay c

Improved accessibility modeling and its relation to poverty - A case study in Southern Sri Lanka

Many studies have found close relationships between accessibility and various socio-economic indicators. Yet, since accessibility tends to have differentiated effects, both socially and spatially, there is a need for a model which allows for a disaggregated analysis of accessibility. The model should be possible to use in areas where road network data is incomplete. In this paper such an accessibi

De-tabooing dying control - a grounded theory study.

Dying is inescapable yet remains a neglected issue in modern health care. The research question in this study was "what is going on in the field of dying today?" What emerged was to eventually present a grounded theory of control of dying focusing specifically on how people react in relation to issues about euthanasia and physician-assisted suicide (PAS).

J/Psi production at RHIC-PHENIX

The J/ψ is considered to be among the most important probes for the deconfined quark–gluon plasma (QGP) created by relativistic heavy-ion collisions. While the J/ψ is thought to dissociate in the QGP by Debye color screening, there are competing effects from cold nuclear matter (CNM), feed-downs from excited charmonia (χc and ψ') and bottom quarks, and regeneration from uncorrelated charm quarks.

A 2.4-to-5.3GHz Dual-Core CMOS VCO with Concentric 8-Shaped Coils

Despite recent attempts to relax the phase-noise demands on voltage-controlled oscillators (VCOs) for cellular communications [1], mainstream radios require harmonic VCOs capable of a very low phase noise with moderate power consumption, associated to a large tuning range (TR) and a high insensitivity to interfering signals. Ideally, the TR should be in excess of one octave, since this allows the

High population variability and source-sink dynamics in a solitary bee species

Although solitary bees are considered to play key roles in ecosystem functions, surprisingly few studies have explored their population dynamics. We investigated the population dynamics of a rare, declining, solitary bee (Andrena humilis) in a landscape of 80 km 2 in southern Sweden from 2003 to 2011. Only one population was persistent throughout all years studied; most likely this population supp

Process performance in lignin separation from softwood black liquor by membrane filtration

Black liquor is a side-stream in the production of kraft pulp. The extraction of lignin and hemicelluloses from black liquor would reduce the load on the recovery boiler and give valuable by-products. Lignin was separated from black liquor by membrane filtration, using one ceramic and three polymeric nanofiltration membranes, with molecular weight cut-offs in the range of 200 Da to 1 kDa. Ultrafil

A multiple representation data structure for dynamic visualisation of generalised 3D city models

In this paper, a novel multiple representation data structure for dynamic visualisation of 3D city models, called CityTree, is proposed. To create a CityTree, the ground plans of the buildings are generated and simplified. Then, the buildings are divided into clusters by the road network and one CityTree is created for each cluster. The leaf nodes of the CityTree represent the original 3D objects

alpha-Synuclein propagates from mouse brain to grafted dopaminergic neurons and seeds aggregation in cultured human cells

Post-mortem analyses of brains from patients with Parkinson disease who received fetal mesencephalic transplants show that alpha-synuclein-containing (alpha-syn-containing) Lewy bodies gradually appear in grafted neurons. Here, we explored whether intercellular transfer of alpha-syn from host to graft, followed by seeding of alpha-syn aggregation in recipient neurons, can contribute to this phenom

An integrated approach towards sustainable entrepreneurship - Experience from the TEST project in transitional economies

The challenge how to assist enterprises more effectively within industrial hot spots of the Danube River Basin in order to meet environmental standards while enhancing their competitiveness was addressed by the project Transfer of Environmentally Sound Technology (TEST). New, integrated approaches were developed and found to be effective in fostering organizational learning and helping to ensure i

The Bergman projection on vector-valued L-2-spaces with operator-valued weights

We characterize the boundedness of the Bergman projection on vector-valued L-2-spaces with operator-valued weights in terms of an appropriate condition of Muckenhoupt-type for the weight. This contrasts with the situation en Hardy spaces, where such characterizations are only possible in the finite-dimensional case. (C) 2011 Elsevier Inc. All rights reserved.