Inverse scattering procedures for the reconstruction of one-dimensional permittivity range profile

In the present work we have presented a reliable and efficient algorithm for the data inversion, which is based on a fully nonlinear data model in conjunction with an optimization technique. The reconstruction of the permittivity range profile has been tested both on synthetic and real data to validate the electromagnetic code as well as to assess the accuracy and efficiency of the reconstruction procedure. We have studied the resolution of the algorithm and its robustness to the noise, demonstrating the ability of our procedure to be able to recognize the presence of high discontinuities even independently from the discretization fixed by the user. As a part of the ongoing improvement of the presented method, we have addressed the implementation of a new optimization algorithm, namely the particle swarm optimization, which has been customized and enhanced for our purposes. Finally, a detailed description of a fast and efficient procedure to evaluate the green’s function for a multilayered medium has been given. This is the groundwork useful for the next step toward a more reliable and versatile forward solver to be implemented in the inversion procedure

Adaptive Finite Element Methods with Inexact Solvers for the Nonlinear Poisson-Boltzmann Equation

In this article we study adaptive finite element methods (AFEM) with inexact solvers for a class of semilinear elliptic interface problems. We are particularly interested in nonlinear problems with discontinuous diffusion coefficients, such as the nonlinear Poisson-Boltzmann equation and its regularizations. The algorithm we study consists of the standard SOLVE-ESTIMATE-MARK-REFINE procedure common to many adaptive finite element algorithms, but where the SOLVE step involves only a full solve on the coarsest level, and the remaining levels involve only single Newton updates to the previous approximate solution. We summarize a recently developed AFEM convergence theory for inexact solvers, and present a sequence of numerical experiments that give evidence that the theory does in fact predict the contraction properties of AFEM with inexact solvers. The various routines used are all designed to maintain a linear-time computational complexity.Comment: Submitted to DD20 Proceeding

Numerical Simulation of the Damage Behavior of a Concrete Beam with an Anisotropic Damage Model

An anisotropic damage model was proposed to describe the nonlinear behavior of concrete beams under monotonic and cyclic loading. The hysteresis effect of concrete is approximately modeled by employing nonlinear loading/linear reloading stress paths in the model, which was implemented into ABAQUS. Linear, bilinear, exponential and Reinhardt strain softening functions are introduced to investigate their influence on accuracy of calculations.Предложена модель анизотропного повреждения для описания нелинейного поведения бетонных балок в условиях монотонного и циклического нагружения. Поведение бетона при гистерезисе ориентировочно моделируют с использованием траектории напряжения при нелинейной нагрузке/линейной перегрузке с последующей реализацией модели в программе ABAQUS. Введены линейная, билинейная, экспоненциальная функции и функция Рейнхардта деформации разуплотнения для изучения их влияния на точность расчетов

Having a family doctor is associated with some better patient-reported outcomes of primary care consultations

<b>Background</b> Hong Kong (HK) has pluralistic primary care that is provided by a variety of doctors. The aim of our study was to assess patient-reported outcomes of primary care consultations in HK and whether having a family doctor (FD) made any difference.<p></p> <b>Methods</b> We interviewed by telephone 3148 subjects from 5174 contacted households (response rate 60.8%) randomly selected from the general population of HK about the experience of their last primary care consultations in September 2007 and April 2008. We compared the patient-reported outcomes (PRO) and patient-centered process of care in those with a FD, those with other types of regular primary care doctors (ORD) and those without any regular primary care doctor (NRD). PRO included patient enablement, global improvement in health, overall satisfaction, and likelihood of recommending their doctors to family and friends. Patient-centered process of care indicators was explanations about the illness, and address of patient’s concerns.<p></p> <b>Results</b> One thousand one hundred fifty, 746, and 1157 reported to have FD, ORD, and NRD, respectively. Over 80% of those with FD consulted their usual primary care doctors in the last consultation compared with 27% of those with NRD. Compared with subjects having ORD or NRD, subjects with FD reported being more enabled after the consultation and were more likely to recommend their doctors to family and friends. Subjects with FD and ORD were more likely than those having NRD to report a global improvement in health and satisfaction. FD group was more likely than the other two groups to report receiving an explanation on the diagnosis, nature, and expected course of the illness, and having their concerns addressed. Patient enablement was associated with explanation of diagnosis, nature, and expected course of illness, and address of patient’s concerns.<p></p> <b>Conclusion</b> People with a regular FD were more likely to feel being enabled and to experience patient-centered care in consultations

A tunable radiation source by coupling laser-plasma-generated electrons to a periodic structure

Near-infrared radiation around 1000 nm generated from the interaction of a high-density MeV electron beam, obtained by impinging an intense ultrashort laser pulse on a solid target, with a metal grating is observed experimentally. Theoretical modeling and particle-in-cell simulation suggest that the radiation is caused by the Smith-Purcell mechanism. The results here indicate that tunable terahertz radiation with tens GV=m field strength can be achieved by using appropriate grating parameter

Dose-response of weanling pigs to streptococcus faecium

Two 5-wk experiments, using a total of 270 pigs (avg initial wt of 16.1 and 13.11b), were conducted to determine the dose-response relationship between Streptococcus faecium additions to drinking water and performance of newly weaned pigs. In experiment 1, treatments were: 1) untreated control; 2, 3, and 4) .5, 2.5, and 4.5 x 109 CFU of S. faecillm/pig/d; 5) antibioticfed positive control (CSP250 and CUS04)\u27 Bacterial content of feces collected from the pigs on d 7, 14, and 21 indicated that antibiotic feeding greatly reduced fecal content of streptococci. S. faecium given in the water (.5, 2.5, or 4.5 x 10 CFU/pig/d) slightly increased the CFU of streptococci in the feces. Giving S. faecillm in the water or antibiotics in the feed did not reduce fecal content of coliform bacteria. Antibiotic feeding improved feed intake, growth rate, and efficiency of gain when compared to the untreated control. Pigs given the highest level of S. faecium addition to the water (i.e., 4.5 x 10^9 had performance that was intermediate to that of the untreated control and positive control. In experiment 2, dosages of S. faecium were spread further apart. Treatments were: 1) untreated negative control; 2,3, and 4) 5 x 107, 5 X 109, and 5 x 1011 CFU of S. faecium/pig/d; and 5) antibiotic-fed positive control. Streptococci content of the feces was increased by giving S. faecillm in the water. However, total coliform content was not affected by giving S. faecium or antibiotics. Antibiotic feeding improved rate of gain, feed intake, and efficiency of gain, but giving S. faecium did not improve performance of pigs compared to those given the untreated control.; Swine Day, Manhattan, KS, November 16, 198

Run-time Support for Distributed Object Sharing in Safe Programming Languages

We present a new run-time system that supports object sharing in a distributed system. The key insight in this system is that a handle-based implementation of such a system enables effcient and transparent sharing of data with both fine-grained and coarse-grained access patterns. In addition, it supports effcient execution of garbage-collected programs. In contrast, conventional distributed shared memory (DSM) systems are limited to providing only one granularity with good performance, and have experienced diffculty in effciently supporting garbage collection. A safe language, in which no pointer arithmetic is allowed, can transparently be compiled into a handle-based system and constitutes its preferred mode of use. A programmer can also directly use a handle-based programming model that avoids pointer arithmetic on the handles, and achieve the same performance but without the programming benefits of a safe programming language. This new run-time system, DOSA (Distributed Object Sharing Architecture), provides a shared object space abstraction rather than a shared address space abstraction. The key to its effciency is the observation that a handle-based distributed implementation permits VM-based access and modification detection without suffering false sharing for fine-grained access patterns. We compare DOSA to TreadMarks, a conventional DSM system that is effcient at handling coarse-grained sharing. The performance of fine-grained applications and garbage-collected applications is considerably better than in TreadMarks. The performance of coarse-grained applications is nearly as good as in TreadMarks. Since the performance of such applications is already good in TreadMarks, we consider this an acceptable performance penalty

Run-time Support for Distributed Sharing in Typed Languages

We present a new run-time system, DOSA, that efficiently implements a shared object space abstraction underneath a typed programming language. The key insight behind DOSA is that the ability to unambiguously distinguish pointers from data at run-time enables efficient fine-grained sharing using VM support. Like earlier systems designed for fine-grained sharing, DOSA improves the performance of fine-grained applications by eliminating false sharing. In contrast to these earlier systems, DOSA's VM-based approach and read aggregation enable it to match a page-based system on coarse-grained applications. Furthermore, its architecture permits optimizations that are not possible in conventional fine-grained or coarse-grained DSM systems