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A 312-MHz CT Delta Sigma modulator using a SC feedback DAC with reduced peak current
This paper presents a second order continuous-time delta-sigma ADC based on a new feedback DAC technique with the low clock jitter sensitivity of the SC (switched-capacitor) technique and the low peak currents of the SI (switched current) technique. The delta-sigma ADC has been implemented in a 90 nm (1.2 V) RF-CMOS process. It measures 66.4 dB maximum SNR over 1.92 MHz bandwidth with a 312 MHz cl
Transient wave propagation in composite media: Green's functions approach
A generalized Green's function technique for wave propagation of transient fields in one-dimensional media is developed. The medium is partitioned into an arbitrary number of subslabs for which Green operators that map the incident field to the internal fields are defined. Relations between the Green operators for the entire medium and the Green operators for the subslabs are derived. The techniqu
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Simulating the hydration of cementitious phases with an oscillating rate of reaction
To investigate how an oscillating reaction rate might influence the hydration of cementitious solids, a simple iterative mathematical model that includes recurrent passivation of the surface has been constructed. The algorithm generates a wide variety of hydration curves with a limited number of input parameters: i.e.. V0 (volume of unreacted solid after initial reaction), a, (degree of reaction u
PAGED : A Page Oriented Text Editor
Monte Carlo Simulation of Transmission Studies using a Planar Sources with a Parallel Collimator and a Line Source with a Fan-Beam Collimators
A knowledge of the distribution of the attenuation coefficient is generally required for a successful correction of attenuation in nonhomogeneous regions. This can be accomplished by performing transmission measurement with either parallel or fan-bean collimation. The Monte Carlo method makes it possible to fully evaluate the results of such a correction. This study shows results from such simulat
Genome characteristics of primary carcinomas, local recurrences, carcinomatoses, and liver metastases from colorectal cancer patients
BACKGROUND: Colorectal cancer (CRC) is one of the most common causes of cancer-related deaths in the Western world, and despite the fact that metastases are usually the ultimate cause of deaths, the knowledge of the genetics of advanced stages of this disease is limited. In order to identify potential genetic abnormalities underlying the development of local and distant metastases in CRC patients,
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The nature of super-metal-rich stars. Detailed abundance analysis of 8 super-metal-rich star candidates
We provide detailed abundance analyses of 8 candidate super-metal-richstars. Five of them are confirmed to have [Fe/H]>0.2 dex, thegenerally-accepted limit for super-metal-richness. Furthermore, wederive abundances of several elements and find that the stars followtrends seen in previous studies of metal-rich stars. Ages are estimatedfrom isochrones and velocities calculated. We find that there do
Perceptions of the real and the ideal ward atmosphere among trainees and staff before and after the introduction of a new work rehabilitation model
Changes in the ward atmosphere of a psychiatric work rehabilitation unit were investigated. Both trainees and staff filled in the Community-Oriented Programs Environment Scale (COPES) before and after a new rehabilitation model was implemented. It was hypothesised that the levels of autonomy and practical orientation would increase from both the trainees' and staff's perspective concerning the rea
Historilärarnas förenings årsskrift 2002
Jag är recensionsredaktör och Bengt Nilsson huvudredaktör för årsskriften
Development of a Multidimensional Residual Distribution Solver for Large Eddy Simulation of Industrial Turbulent Flows.
Popular Abstract in Swedish Utveckling av en flerdimensionell residual-distributions lösare för Large Eddy Simulation av industriell turbulenta strömningar.This thesis presents the results of the author's research activity to develop a time-space accurate flow-solver for Large Eddy Simulations (LES), based on the Multidimensional Residual Distribution approach. The aim of this work is the attempt to develop a compact high-order algorithm which includes multidimensional flow physics, in hope of creating a better algorithm for LES of turbulent compress
Buildings and Energy - a systematic approach
In many existing buildings, energy conservation measures have significantly reduced the demands for heat supply. In new buildings, advances in a wide range of technologies have led to even greater reductions. On the other hand, demands for electrical energy have risen noticeably. Unfortunately, it now seems that the use of both heat and electrical energy is starting to increase, especially in non
Ghrelin Is Expressed in a Novel Endocrine Cell Type in Developing Rat Islets and Inhibits Insulin Secretion from INS-1 (832/13) Cells.
Atomic-scale visualization of inertial dynamics
The motion of atoms on interatomic potential energy surfaces is fundamental to the dynamics of liquids and solids. An accelerator-based source of femtosecond x-ray pulses allowed us to follow directly atomic displacements on an optically modified energy landscape, leading eventually to the transition from crystalline solid to disordered liquid. We show that, to first order in time, the dynamics ar
Regional differences in mechanical properties between major arteries--an experimental study in sheep
PURPOSE: To study possible differences in mechanical properties between central (abdominal aorta) and more peripheral (common carotid and common femoral) arteries validating an earlier non-invasive study in children showing that central arteries are more distensible than peripheral ones. As invasive blood pressure was needed, but ethically impossible to obtain in children in an experimental settin
A dynamic analysis of the oscillations in a chain drive
A model is presented in which the oscillations, and the forces thus produced, in a chain drive, working at moderate and high speed, can be calculated. Since the outer system affects the result it has been necessary to include this in the model. The mass of the chain is included in the model and both the gravitational forces and the inertia forces in the chain are taken into account. The elasticity
The relationship between different forms of human alpha-mannosidase
The tissue distribution and some properties of human alpha-mannosidase (alpha-D-mannoside mannohydrolase EC 3.2.1.24) have been studied. The acidic forms of the enzyme were fairly stable, whereas the neutral forms easily lost enzymic activity. The acidic forms were sensitive to neuraminidase but the neutral forms were unaffected. The experiments indicate that the acidic components are closely rela
Country of origin, social support and the risk of small for gestational age birth.
Aims: This study investigates the risk of small for gestational age (SGA) in relation to country of origin of the mother. The role of psychosocial resources, socioeconomic and lifestyle factors was examined in different causal models. Methods: Among all pregnant nulliparous women in the city of Malmo¨ , Sweden, who gave birth in 1991 – 92, 872 (87.7%) women completed a questionnaire during their f