MIMO indoor propagation : a geometry-based model including time-variant fading statistics

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Measurement-based analysis of Doppler characteristics for ultra-wideband radio channels in an office environment

In this work, an analysis of the Doppler characteristics for Ultra-Wideband indoor communication is presented. Channel sounding measurements ranging from 3.1 to 10.6 GHz were performed over the course of several days in an occupied office environment, with the help of a network analyzer. Based on these measurements, we analyze the behavior of both the Doppler spread and RMS Doppler spread in the Ultra-Wideband frequency band. Our measurements indicate a frequency-dependent behavior for both parameters, where consistent values could be measured with respect to time of observation

Measurement-based analysis of delay-Doppler characteristics in an indoor environment

An analysis of delay-Doppler characteristics in the presence of moving people is presented for short-range communication in an indoor environment. Channel-sounding measurements have been carried out at 3.6 GHz in a crowded university hall during several short and long breaks in-between courses. During three consecutive days, the measurements were repeated with different positions for the transmit and receive antennas. In this study, the behavior of the maximum Doppler shift and the Doppler spread was analyzed in the time-delay domain as a function of the occupation of the hall, the polarizations of the 2 x 2 MIMO antennas, and their positions in the hall. The measurements reveal a clear distinction between the Doppler spread of the short and long breaks in the campaign, indicating a distinctive power distribution of their Doppler spectra. In addition, there is a significant contrast between the Doppler characteristics of the co- and cross-polarizations. Measurements at several positions reveal the importance of characterizing multipaths and show that the Doppler effect depends on the position of the antennas in the environment. In addition, this work also shows that the Doppler spectrum can be accurately modeled by a Cauchy distribution, allowing for the generation of parameters to describe Doppler characteristics

Assessing the Impact of Incorporating Residential Histories into the Spatial Analysis of Cancer Risk

In many spatial epidemiologic studies, investigators use residential location at diagnosis as a surrogate for unknown environmental exposures or as a geographic basis for assigning measured exposures. Inherently, they make assumptions about the timing and location of pertinent exposures which may prove problematic when studying long latency diseases such as cancer. In this work we explored how the association between environmental exposures and disease risk for long-latency health outcomes like cancer is affected by residential mobility. We used simulation studies conditioned on real data to evaluate the extent to which the commonly held assumption of no residential mobility 1) affected the ability of generalized additive models to detect areas of significantly elevated historic environmental exposure and 2) increased bias in the estimates of the relationship between environmental exposures and disease in a case-control study. While the literature suggests that some researchers have begun to develop methods to incorporate historic locations in studies of health outcomes, a number of questions remain. One reason for the knowledge gap is that residential histories have not been collected in most U.S. epidemiologic studies. In our work we evaluated the impact of using public-record database generated histories to estimate the effects of exposure in lieu of using subject-reported addresses collected during a study. Finally, we evaluated the effect of environmental exposure on cancer risk in a case-control study using an approach that combined a multiple membership conditional autoregressive (CAR) model with an environmental exposure index for temporally correlated time-varying exposure assigned based on residential histories. We used this model in a data application to explain bladder cancer risk in the New England Bladder Cancer Study. We included a temporal arsenic exposure index in the model to assess a large number of correlated arsenic exposures

Multifragmentation in the Intranuclear Cascade - Percolation Approach

peer reviewe

A General History of the Congregation of the Mission Beginning after the Death of Blessed Vincent de Paul

This work is the earliest known history of the Congregation of the Mission and dates from about 1730. Vincentian historian John E. Rybolt, C.M., building on the initiative of Stafford Poole, C.M., completed this English translation from the original French. The author, Claude-Joseph Lacour, C.M. (1672-1731), drew from already published materials and his own recollections. While the story he tells may seem familiar, Lacour included materials that are unknown anywhere else and delivers a first-hand account of the Congregation’s rapid growth in those early days. The text is essential reading for anyone wishing to better understand Vincent de Paul’s society of apostolic life of priests and brothers following his death.https://via.library.depaul.edu/vincentian_ebooks/1044/thumbnail.jp