Speech transmission using rate-compatible trellis codes andembedded source coding

This paper presents bandwidth-efficient speech transmission systems using rate-compatible channel coders and variable bitrate embedded source coders. Rate-compatible punctured convolutional codes (RCPC) are often used to provide unequal error protection (UEP) via progressive bit puncturing. RCPC codes are well suited for constellations for which Euclidean and Hamming distances are equivalent (BPSK and 4-PSK). This paper introduces rate-compatible punctured trellis codes (RCPT) where rate compatibility and UEP are provided via progressive puncturing of symbols in a trellis. RCPT codes constitute a special class of codes designed to maximize residual Euclidean distances (RED) after symbol puncturing. They can be designed for any constellation, allowing for higher throughput than when restricted to using 4-PSK. We apply RCPC and RCPT to two embedded source coders: a perceptual subband coder and the ITU embedded ADPCM G.727 standard. Different operating modes with distinct source/channel bit allocation and UEP are defined. Each mode is optimal for a certain range of AWGN channel SNRs. Performance results using an 8-PSK constellation clearly illustrate the wide range of channel conditions at which the adaptive scheme using RCPT can operate. For an 8-PSK constellation, RCPT codes are compared to RCPC with bit interleaved coded modulation codes (RCPC-BICM). We also compare performance to RCPC codes used with a 4-PSK constellation     

Pull-out work of steel fibers from cementitious composites: Analytical investigation

The main objective of this study is to provide a parametric evaluation of the pull-out work of smooth steel fibers embedded in cementitious matrices. The various parameters controlling the behavior of the bond stress versus slip relationship are analyzed; their effects on the entire pull-out load versus slip response and the corresponding pull-out energy up to full debonding and/or up to total pull-out are investigated. Also discussed are the effects of the fiber geometric parameters such as fiber diameter, length, and aspect ratio. Finally, a brief section addresses the relation between pull-out work and the critical strain energy release rate G_c, a fracture mechanics variable, which can be calculated if the P-Δ curve is known.     

Development and Preliminary Validation of Heart Rate and Breathing Rate Detection Using a Passive, Ballistocardiography-Based Sleep Monitoring System

Techniques such as ballistocardiography (BCG) that can provide noninvasive long-term physiological monitoring have gained interest due to a growing recognition of adverse effects from poor sleep and sleep disorders. The noninvasive analysis of physiological signals (NAPS) system is a BCG-based monitoring system developed to measure heart rate, breathing rate, and musculoskeletal movement that shows promise as a general sleep analysis tool. Overnight sleep studies were conducted on 40 healthy subjects during a clinical trial at the University of Virginia. The NAPS system's measures of heart rate and breathing rate were compared to ECG, pulse oximetry, and respiratory inductance plethysmography (RIP). The subjects were split into a training dataset and a validation dataset, maintaining similar demographics in each set. The NAPS system accurately detected heart rate, averaged over the prescribed 30-s epochs, to within less than 2.72 beats per minute of ECG, and accurately detected breathing rate, averaged over the same epochs, to within 2.10 breaths per minute of RIP bands used in polysomnography.     

Rate Allocation for Noncollaborative Multiuser Speech Communication Systems Based on Bargaining Theory

We propose a novel rate allocation algorithm for multiuser speech communication systems based on bargaining theory. Specifically, we apply the generalized Kalai-Smorodinsky bargaining solution since it allows varying bargaining powers to match the dynamic nature of speech signals. We propose a novel method to derive bargaining powers based on the short-time energy of the input speech signals, and subsequently allocate rates accordingly to the users. An important merit of the proposed framework is that it is general and can be applicable for resource allocation across a variety of multirate speech coders, and it is robust to a variety of speech quality metrics. The proposed system is also shown to involve a quick and low-complexity training process. We generalize the algorithm to scenarios in which users have unequally weighted priorities. These scenarios might arise in emergency situations, in which certain users are more important than others. The proposed rate allocation system is shown to increase the utility measures for both the Itakura and segmental signal-to-noise ratio (SNR) functions relative to the baseline system that performs uniform rate allocation. Additionally, although the instantaneous bitrate resolution of the speech encoder is not changed, the proposed system is shown to increase the short-time average bitrate resolution, and therefore provides a greater number of operational rate modes for the network     

General Data Analysis Supported SPC

The issue of autocorrelation in statistical process control (SPC) data has been and continues to be a much discussed and researched topic. In nearly all published studies and in SPC training modules, the predominate models for autocorrelation come from a class of time-series models known as autoregressive-integrated moving average (ARIMA) models. However, little attention is given to a variety of systematic patterns pervasive in SPC applications that are not adequately modeled by the ARIMA framework. In this paper, we suggest the need for an even broader perspective than defined by ARIMA models. Furthermore, we argue that effective SPC training not only requires attention to data analysis tools for modeling systematic patterns but also to tools for diagnostically checking the distributional assumptions of variable and attribute charts.     

Health-status monitoring through analysis of behavioral patterns

With the rapid growth of the elderly population, there is a need to support the ability of elders to maintain an independent and healthy lifestyle in their homes rather than through more expensive and isolated care facilities. One approach to accomplish these objectives employs the concepts of ambient intelligence to remotely monitor an elder's activities and condition. The SmartHouse project uses a system of basic sensors to monitor a person's in-home activity; a prototype of the system is being tested within a subject's home. We examined whether the system could be used to detect behavioral patterns and report the results in this paper. Mixture models were used to develop a probabilistic model of behavioral patterns. The results of the mixture-model analysis were then evaluated by using a log of events kept by the occupant.     

A 60 GHz phased array with measurement and de-embedding techniques

We present a 60 GHz phased array system that combines several key technologies to realize 10 GHz bandwidth coverage. Particularly, a tightly coupled dipole array centered at 60 GHz is designed and tested for its wideband performance. The tightly coupled dipole elements offer excellent wideband behavior of 10 GHz with voltage standing wave ratio?<?3 with scanning to 45°, as well as low cost printed circuit board fabrication. Additionally, we demonstrate a measurement setup with de-embedding procedure to measure gain at the antenna feed point. A feeding structure was designed and fabricated for de-embedding gain pattern measurements. Recovered measurements are shown to be in agreement with simulation.     

Study the Characteristic of Planer and Sandwich PSi Gas Sensor (Comparative Study)

In this work, two configurations (planner and sandwich) structures of (Al/n PSi/n-Si/Al) porous silicon (PSi) gas sensor have been fabricated and tested extensively for CO₂ gas molecules. Two laser wavelength infrared and violet of (810 nm) and (405 nm) was used in the laser assisting etching process on the n-type silicon substrate. The gas detection characteristic of planner and sandwich configuration were studied under different condition. The resistance measurement, for the planner and J-V characteristic for sandwich structures, which was analyzed based on the nano-sized silicon, porosity, layer thickness, and the effective dielectric constant of the PSi layer. The SEM image of the PSi layer showed the formation pore-like structure with cylindrical and rectangular pore shape with different dimensions for infrared illuminated PSi and crossed pores-like structure with randomly distributed for violet illuminated PSi. The sensing mechanism for sandwich structure configuration is governed by the porous silicon parameters, while for planer configuration the silicon channel among the pore has a significant role in sensing process.     

Behavioral patterns of older-adults in assisted living

In this paper, we examine at-home activity rhythms and present a dozen of behavioral patterns obtained from an activity monitoring pilot study of 22 residents in an assisted living setting with four case studies. Established behavioral patterns have been captured using custom software based on a statistical predictive algorithm that models circadian activity rhythms (CARs) and their deviations. The CAR was statistically estimated based on the average amount of time a resident spent in each room within their assisted living apartment, and also on the activity level given by the average number of motion events per room. A validated in-home monitoring system (IMS) recorded the monitored resident's movement data and established the occupancy period and activity level for each room. Using these data, residents' circadian behaviors were extracted, deviations indicating anomalies were detected, and the latter were correlated to activity reports generated by the IMS as well as notes of the facility's professional caregivers on the monitored residents. The system could be used to detect deviations in activity patterns and to warn caregivers of such deviations, which could reflect changes in health status, thus providing caregivers with the opportunity to apply standard of care diagnostics and to intervene in a timely manner.     

Antimicrobial resistance of Listeria monocytogenes isolated from dairy-based food products

In this study Listeria monocytogenes (L. monocytogenes) was isolated from three traditionally consumed Lebanese dairy-based food products. One hundred and sixty four samples (45 samples of Baladi cheese, 36 samples of Shankleesh and 83 of Kishk) were collected from the Bekaa Valley in the Northeast region of Lebanon. Suspected Listeria colonies were selected and initially identified by using standard biochemical tests. Initial identification of the positive L. monocytogenes colonies was confirmed at the molecular level by Polymerase Chain Reaction (n = 30) and the confirmed isolates were evaluated for their susceptibility to 10 commonly used antimicrobials. All of the 30 isolates were confirmed to be L. monocytogenes yielding a PCR product of ∼ 660 base pairs (bp). L. monocytogenes was detected in 26.67%, 13.89% and 7.23% of the Baladi cheese, Shankleesh and Kishk samples, respectively. The highest resistance in L. monocytogenes isolates was noted against oxacillin (93.33%) followed by penicillin (90%). The results provide an indication of the contamination levels of dairy-based foods in Lebanon and highlight the emergence of multi-drug resistant Listeria in the environment.