Soft information based protocols in network coded relay networks

Future wireless networks aim at providing higher quality of service (QoS) to mobile users. The emergence of relay technologies has shed light on new methodologies through which the system capacity can be dramatically increased with low deployment cost. In this thesis, novel relay technologies have been proposed in two practical scenarios: wireless sensor networks (WSN) and cellular networks. In practical WSN designs, energy conservation is the single most important requirement. This thesis draws attention to a multiple access relay channels model in the WSN. The network coded symbol for the received signals from correlated sources has been derived; the network coded symbol vector is then converted into a sparse vector, after which a compressive sensing (CS) technique is applied over the sparse signals. A theoretical proof analysis is derived regarding the reliability of the network coded symbol formed in the proposed protocol. The proposed protocol results in a better bit error rate (BER) performance in comparison to the direct implementation of CS on the EF protocol. Simulation results validate our analyses. Another hot topic is the application of relay technologies to the cellular networks. In this thesis, a practical two-way transmission scheme is proposed based on the EF protocol and the network coding technique. A trellis coded quantization/modulation (TCQ/M) scheme is used in the network coding process. The soft network coded symbols are quantized into only one bit thus requiring the same transmission bandwidth as the simplest decode-and-forward protocol. The probability density function of the network coded symbol is derived to help to form the quantization codebook for the TCQ. Simulations show that the proposed soft forwarding protocol can achieve full diversity with only a transmission rate of 1, and its BER performance is equivalent to that of an unquantized EF protocol

Soft information based protocols in network coded relay networks

Future wireless networks aim at providing higher quality of service (QoS) to mobile users. The emergence of relay technologies has shed light on new methodologies through which the system capacity can be dramatically increased with low deployment cost. In this thesis, novel relay technologies have been proposed in two practical scenarios: wireless sensor networks (WSN) and cellular networks. In practical WSN designs, energy conservation is the single most important requirement. This thesis draws attention to a multiple access relay channels model in the WSN. The network coded symbol for the received signals from correlated sources has been derived; the network coded symbol vector is then converted into a sparse vector, after which a compressive sensing (CS) technique is applied over the sparse signals. A theoretical proof analysis is derived regarding the reliability of the network coded symbol formed in the proposed protocol. The proposed protocol results in a better bit error rate (BER) performance in comparison to the direct implementation of CS on the EF protocol. Simulation results validate our analyses. Another hot topic is the application of relay technologies to the cellular networks. In this thesis, a practical two-way transmission scheme is proposed based on the EF protocol and the network coding technique. A trellis coded quantization/modulation (TCQ/M) scheme is used in the network coding process. The soft network coded symbols are quantized into only one bit thus requiring the same transmission bandwidth as the simplest decode-and-forward protocol. The probability density function of the network coded symbol is derived to help to form the quantization codebook for the TCQ. Simulations show that the proposed soft forwarding protocol can achieve full diversity with only a transmission rate of 1, and its BER performance is equivalent to that of an unquantized EF protocol

The Effect of Horizontal Inequity, Capacity for Budget Slack, and Severity of Peer Overstatement on Managerial Reporting Behavior

An ongoing stream of accounting research indicates that non-pecuniary factors significantly affect employees’ reporting behavior. This study investigates the behavioral effects of three non-pecuniary factors - horizontal pay inequity, capacity for budget slack, and severity of peer overstatement. The behaviors of interest are the employees’ level of honesty and whether or not they report a peer that is overstating. In the experiment, participants acted as division managers who request funding from the owner of a fictitious company to produce certain parts. In each period, participants were paired with a different fictitious peer and were required to make two decisions under a peer reporting system: (1) how much funding to request from the owner to complete the production task, and (2) whether to report their peers, who overstate their funding needs, to the owner. Participants’ total compensation was determined by their own decisions and the decisions made by their peers. The results suggest that employees are most honest about their funding requests when they are paid more than their peers and are least honest when they are paid less than their peers. Additionally, employees are most likely to blow the whistle on their peers who overstate their funding requests when they are paid less than their peers and are least likely to do so when they are paid the same as their peers. Furthermore, employees tend to create more budget slack when they have greater capacity for overstating their funding requests. Also, employees’ propensity to blow the whistle is positively associated with the severity of their peers’ overstatement. The results add to the stream of accounting research that integrates both economic and psychological theories to examine employees’ decision making in a multi-agent setting. More importantly, this study makes a contribution by testing the overpayment effect of horizontal inequity in an accounting setting. Also, the results enhance our understanding of the unintentional consequences of implementing a pay transparency policy

INVESTIGATION OF DISCONTINUITY IN PRECIPITATION MEASUREMENTS ACROSS CANADA AND U.S. BORDER

This dissertation focuses on the discontinuity in precipitation measurements across Canada and U.S. border. Incorrect precipitation data may cause inhomogeneous precipitation distribution, which can result in incorrect spatial interpretation. This study quantifies the bias-corrections for the systematic errors (i.e. wind-induced gauge undercatch, wetting loss, and trace precipitation) in the historically national standard manual gauges (Nipher gauge and Type B rain gauge for Canada and NWS 8-inch gauge for U.S.). This study uses the statistical method to compare the measured and corrected precipitation measurements for each pair of the station across the border. It also applies regression analysis to examine the correlation between each station pair and the changes in precipitation relationship due to the bias-corrections. Moreover, a double mass curve (DMC) analysis was conducted to present the changes in cumulative precipitation over time. Overall, the conclusion of this study is that the bias-correction is greater for NWS 8-inch gauge than for the Canadian Nipher gauge, and also, the bias-correction is higher in the cold season than in the warm season. The DMC also quantifies significant discontinuity in the measurements across Canada and U.S. border. The contributions of this study include: improve the understanding of precipitation change due to the systematic errors (bias-corrections); document the changes in precipitation amounts and distribution due to bias-corrections; and quantify significant discontinuity in the precipitation measurements across Canada and the U.S. border. This study will benefit regional climate and hydrology research

The Viability of a Loaning-Based Delivery Model to Tackle Healthcare’s Last-Mile Challenge in South Africa

Healthcare access in developing countries is a severe problem due to insufficient healthcare providers and non-existent supply chain infrastructure. This problem is particularly evident in South Africa due to the disparity between urban and rural regions along with an overcrowded public healthcare system. The result is that patients in rural regions who live many kilometers away from their nearest healthcare facility are unable to access essential medicines. This paper seeks to investigate the medical last-mile challenge in South Africa as well as test the viability of a potential solution. Mobility is a platform that seeks to mobilize the large population of unemployed youth in South Africa to complete deliveries of chronic medicines from pharmacies to individual households. It seeks to do this through the facilitation of loans that are repaid gradually through service-based contracts. By speaking with numerous stakeholders within the South African medical supply chain including pharmaceutical companies, healthcare providers, government officials along with potential partners, we sought out to determine the potential for Mobility to revolutionize healthcare access in South Africa. Stakeholder analysis proved the validity of Mobility as a concept and clarified the specific value propositions for pharmaceutical companies, healthcare providers, the government as well as patients. In addition, key next steps were identified in order to implement Mobility in South Africa

Physics Inspired Optimization on Semantic Transfer Features: An Alternative Method for Room Layout Estimation

In this paper, we propose an alternative method to estimate room layouts of cluttered indoor scenes. This method enjoys the benefits of two novel techniques. The first one is semantic transfer (ST), which is: (1) a formulation to integrate the relationship between scene clutter and room layout into convolutional neural networks; (2) an architecture that can be end-to-end trained; (3) a practical strategy to initialize weights for very deep networks under unbalanced training data distribution. ST allows us to extract highly robust features under various circumstances, and in order to address the computation redundance hidden in these features we develop a principled and efficient inference scheme named physics inspired optimization (PIO). PIO's basic idea is to formulate some phenomena observed in ST features into mechanics concepts. Evaluations on public datasets LSUN and Hedau show that the proposed method is more accurate than state-of-the-art methods.Comment: To appear in CVPR 2017. Project Page: https://sites.google.com/view/st-pio

Quasi-B-mode generated by high-frequency gravitational waves and corresponding perturbative photon fluxes

Interaction of very low-frequency primordial(relic) gravitational waves(GWs) to cosmic microwave background(CMB) can generate B-mode polarization. Here, for the first time we point out that the electromagnetic(EM) response to high-frequency GWs(HFGWs) would produce quasi-B-mode distribution of the perturbative photon fluxes, and study the duality and high complementarity between such two B-modes. Based on this quasi-B-mode in HFGWs, it is shown that the distinguishing and observing of HFGWs from the braneworld would be quite possible due to their large amplitude, higher frequency and very different physical behaviors between the perturbative photon fluxes and background photons, and the measurement of relic HFGWs may also be possible though face to enormous challenge.Comment: 22 pages, 6 figures, research articl

Probing Triple-W Production and Anomalous WWWW Coupling at the CERN LHC and future 100TeV proton-proton collider

Triple gauge boson production at the LHC can be used to test the robustness of the Standard Model and provide useful information for VBF di-boson scattering measurement. Especially, any derivations from SM prediction will indicate possible new physics. In this paper we present a detailed Monte Carlo study on measuring WWW production in pure leptonic and semileptonic decays, and probing anomalous quartic gauge WWWW couplings at the CERN LHC and future hadron collider, with parton shower and detector simulation effects taken into account. Apart from cut-based method, multivariate boosted decision tree method has been exploited for possible improvement. For the leptonic decay channel, our results show that at the sqrt{s}=8(14)[100] TeV pp collider with integrated luminosity of 20(100)[3000] fb-1, one can reach a significance of 0.4(1.2)[10]sigma to observe the SM WWW production. For the semileptonic decay channel, one can have 0.5(2)[14]sigma to observe the SM WWW production. We also give constraints on relevant Dim-8 anomalous WWWW coupling parameters.Comment: Accepted version by JHE

Imaging the Centromedian Thalamic Nucleus Using Quantitative Susceptibility Mapping.

The centromedian (CM) nucleus is an intralaminar thalamic nucleus that is considered as a potentially effective target of deep brain stimulation (DBS) and ablative surgeries for the treatment of multiple neurological and psychiatric disorders. However, the structure of CM is invisible on the standard T1- and T2-weighted (T1w and T2w) magnetic resonance images, which hamper it as a direct DBS target for clinical applications. The purpose of the current study is to demonstrate the use of quantitative susceptibility mapping (QSM) technique to image the CM within the thalamic region. Twelve patients with Parkinson's disease, dystonia, or schizophrenia were included in this study. A 3D multi-echo gradient recalled echo (GRE) sequence was acquired together with T1w and T2w images on a 3-T MR scanner. The QSM image was reconstructed from the GRE phase data. Direct visual inspection of the CM was made on T1w, T2w, and QSM images. Furthermore, the contrast-to-noise ratios (CNRs) of the CM to the adjacent posterior part of thalamus on T1w, T2w, and QSM images were compared using the one-way analysis of variance (ANOVA) test. QSM dramatically improved the visualization of the CM nucleus. Clear delineation of CM compared to the surroundings was observed on QSM but not on T1w and T2w images. Statistical analysis showed that the CNR on QSM was significantly higher than those on T1w and T2w images. Taken together, our results indicate that QSM is a promising technique for improving the visualization of CM as a direct targeting for DBS surgery