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Closing the Loophole: A Case Study of Organizing for More Equitable and Affordable Access to Health Care in San Francisco
This paper presents in-depth case study of a successful hybrid political and community organizing campaign to ensure equitable access to health care through the perspective of a grassroots San Francisco community-based organization, the Chinese Progressive Association (CPA), which has been organizing low-income Chinese immigrants for over four decades. First, it outlines the Health Care Security Ordinance (HCSO), which, since its passage in 2006, has established a near-universal health care access program, helping to make health care accessible and affordable to individuals living and working in San Francisco. Then it presents the campaign to save the HCSO, focusing on CPA’s participation in the HCSO coalition. Finally, it discusses health care as it relates to the San Francisco’s affordability crisis and the political economic context in which it is taking place. Despite the limitations inherent in small case studies like this one, it nevertheless provides a valuable opportunity to better understand how one politically progressive city attempted to address the problem of grossly inequitable health care access through the lens of community organizing, advocacy, and coalition building. San Francisco, like many major American cities today, is being confronted with rapid gentrification and growing economic inequality—the backdrop to the HCSO. Through innovative experiments in social responsibility like the HCSO, however, the city has made leaps in health care access. It concludes with lessons learned from local organizing and advocacy to save the HCSO as these may inform other local efforts to promote health care for all
RIS-Aided Interference Cancellation for Joint Device-to-Device and Cellular Communications
Joint device-to-device (D2D) and cellular communication is a promising
technology for enhancing the spectral efficiency of future wireless networks.
However, the interference management problem is challenging since the operating
devices and the cellular users share the same spectrum. The emerging
reconfigurable intelligent surfaces (RIS) technology is a potentially ideal
solution for this interference problem since RISs can shape the wireless
channel in desired ways. This paper considers an RIS-aided joint D2D and
cellular communication system where the RIS is exploited to cancel interference
to the D2D links and maximize the minimum signal-to-interference plus noise
(SINR) of the device pairs and cellular users. First, we adopt a popular
alternating optimization (AO) approach to solve the minimum SINR maximization
problem. Then, we propose an interference cancellation (IC)-based approach
whose complexity is much lower than that of the AO algorithm. We derive a
representation for the RIS phase shift vector which cancels the interference to
the D2D links. Based on this representation, the RIS phase shift optimization
problem is transformed into an effective D2D channel optimization. We show that
the AO approach can converge faster and can even give better performance when
it is initialized by the proposed IC solution. We also show that for the case
of a single D2D pair, the proposed IC approach can be implemented with limited
feedback from the single receive device.Comment: 6 pages, 3 figures, submitted for conference publicatio
Decision-Directed Hybrid RIS Channel Estimation with Minimal Pilot Overhead
To reap the benefits of reconfigurable intelligent surfaces (RIS), channel
state information (CSI) is generally required. However, CSI acquisition in RIS
systems is challenging and often results in very large pilot overhead,
especially in unstructured channel environments. Consequently, the RIS channel
estimation problem has attracted a lot of interest and also been a subject of
intense study in recent years. In this paper, we propose a decision-directed
RIS channel estimation framework for general unstructured channel models. The
employed RIS contains some hybrid elements that can simultaneously reflect and
sense the incoming signal. We show that with the help of the hybrid RIS
elements, it is possible to accurately recover the CSI with a pilot overhead
proportional to the number of users. Therefore, the proposed framework
substantially improves the system spectral efficiency compared to systems with
passive RIS arrays since the pilot overhead in passive RIS systems is
proportional to the number of RIS elements times the number of users. We also
perform a detailed spectral efficiency analysis for both the pilot-directed and
decision-directed frameworks. Our analysis takes into account both the channel
estimation and data detection errors at both the RIS and the BS. Finally, we
present numerous simulation results to verify the accuracy of the analysis as
well as to show the benefits of the proposed decision-directed framework.Comment: submitted for journal publication, 13 pages, 7 figure
Biodegradation of phenol by Pseudomonas pictorum on immobilized with chitin
Biodegradation of phenol using Pseudomonas pictorum (ATCC 23328) a potential biodegradant of phenol was investigated under different operating conditions. Chitin was chosen as a support material and then partially characterized physically and chemically. The pH of the solution was varied over a range of 7 – 9. The maximum adsorption and degradation capacity of bacteria immobilized with chitin at 30oC when the phenol concentration was 0.200 mg/L is at pH 7.0. The results showed that the equilibrium data for all phenol-degradation sorbent systems fitted the Langmuir, Freundlich and Redlich-Peterson model best. Kinetic modeling of phenol degradation was done using the pseudo-first order and pseudo-second order rate expression. The biodegradation data generally fit the intraparticle diffusion rate equation from which biodegradation rate constant, diffusion rate constant were determined
The H-alpha Luminosity Function and Star Formation Rate Volume Density at z=0.8 from the NEWFIRM H-alpha Survey
[Abridged] We present new measurements of the H-alpha luminosity function
(LF) and SFR volume density for galaxies at z~0.8. Our analysis is based on
1.18m narrowband data from the NEWFIRM H-alpha Survey, a comprehensive
program designed to capture deep samples of intermediate redshift emission-line
galaxies using narrowband imaging in the near-infrared. The combination of
depth ( erg s cm in H-alpha at
3) and areal coverage (0.82 deg) complements other recent H-alpha
studies at similar redshifts, and enables us to minimize the impact of cosmic
variance and place robust constraints on the shape of the LF. The present
sample contains 818 NB118 excess objects, 394 of which are selected as H-alpha
emitters. Optical spectroscopy has been obtained for 62% of the NB118 excess
objects. Empirical optical broadband color classification is used to sort the
remainder of the sample. A comparison of the LFs constructed for the four
individual fields reveals significant cosmic variance, emphasizing that
multiple, widely separated observations are required. The dust-corrected LF is
well-described by a Schechter function with L*=10^{43.00\pm0.52} ergs s^{-1},
\phi*=10^{-3.20\pm0.54} Mpc^{-3}, and \alpha=-1.6\pm0.19. We compare our
H-alpha LF and SFR density to those at z<1, and find a rise in the SFR density
\propto(1+z)^{3.4}, which we attribute to significant L* evolution. Our H-alpha
SFR density of 10^{-1.00\pm0.18} M_sun yr^{-1} Mpc^{-3} is consistent with UV
and [O II] measurements at z~1. We discuss how these results compare to other
H-alpha surveys at z~0.8, and find that the different methods used to determine
survey completeness can lead to inconsistent results. This suggests that future
surveys probing fainter luminosities are needed, and more rigorous methods of
estimating the completeness should be adopted as standard procedure.Comment: 19 pages (emulate-ApJ format), 16 figures, 5 tables, published in
ApJ. Modified to match ApJ versio
Linear and Deep Neural Network-based Receivers for Massive MIMO Systems with One-Bit ADCs
The use of one-bit analog-to-digital converters (ADCs) is a practical
solution for reducing cost and power consumption in massive
Multiple-Input-Multiple-Output (MIMO) systems. However, the distortion caused
by one-bit ADCs makes the data detection task much more challenging. In this
paper, we propose a two-stage detection method for massive MIMO systems with
one-bit ADCs. In the first stage, we propose several linear receivers based on
the Bussgang decomposition, that show significant performance gain over
existing linear receivers. Next, we reformulate the maximum-likelihood (ML)
detection problem to address its non-robustness. Based on the reformulated ML
detection problem, we propose a model-driven deep neural network-based
(DNN-based) receiver, whose performance is comparable with an existing support
vector machine-based receiver, albeit with a much lower computational
complexity. A nearest-neighbor search method is then proposed for the second
stage to refine the first stage solution. Unlike existing search methods that
typically perform the search over a large candidate set, the proposed search
method generates a limited number of most likely candidates and thus limits the
search complexity. Numerical results confirm the low complexity, efficiency,
and robustness of the proposed two-stage detection method.Comment: 12 pages, 10 figure
DNN-based Detectors for Massive MIMO Systems with Low-Resolution ADCs
Low-resolution analog-to-digital converters (ADCs) have been considered as a
practical and promising solution for reducing cost and power consumption in
massive Multiple-Input-Multiple-Output (MIMO) systems. Unfortunately,
low-resolution ADCs significantly distort the received signals, and thus make
data detection much more challenging. In this paper, we develop a new deep
neural network (DNN) framework for efficient and low-complexity data detection
in low-resolution massive MIMO systems. Based on reformulated maximum
likelihood detection problems, we propose two model-driven DNN-based detectors,
namely OBMNet and FBMNet, for one-bit and few-bit massive MIMO systems,
respectively. The proposed OBMNet and FBMNet detectors have unique and simple
structures designed for low-resolution MIMO receivers and thus can be
efficiently trained and implemented. Numerical results also show that OBMNet
and FBMNet significantly outperform existing detection methods.Comment: 6 pages, 8 figures, submitted for publication. arXiv admin note: text
overlap with arXiv:2008.0375
Hong Kong, The United Nations International Crime Victim Survey: Final Report of the 2006 Hong Kong UNICVS
Final Report of the 2006 Hong Kong UNICVSpublished_or_final_versio
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