Neuromorphic cameras for Atmospheric Cherenkov Telescopes and fast optical astronomy: new paradigm, challenges and opportunities

The astronomy community has witnessed an explosive growth in the use of deep-learning techniques based on neural networks since the mid-2010s. The widespread adoption of these nature-inspired technologies has helped astronomers tackle previously insurmountable problems and provided an unprecedented opportunity for new discoveries. However, one of the primary tools of today's optical astronomy is neither natural nor efficient: their photo-sensing devices. Specifically, the modern CCD camera - like that of the cutting-edge Rubin Observatory - requires an internal clock to regularly expose the sensor to light, consumes a large amount of energy and information bandwidth, and has a limited dynamic range. On the contrary, biological eyes lack an internal clock and a shutter, have much higher pixel density but consume significantly less energy and bandwidth, and can adapt to bright and low light conditions. Inspired by the nature of the eyes, M. Mahowald and C. Mead introduced the revolutionary concept of a silicon retina sensor in 1991. Also known as event-based cameras (EBCs), these types of devices operate in a vastly different way compared to conventional CCD-based imaging sensors. EBCs mimic the operating principles of optic nerves and continuously produce a stream of events, with each event generated only when a pixel detects a change in light intensity. EBCs do not have fixed exposure times, have high dynamic range, require low power for operation, and can capture high-speed phenomena. These properties are important requirements for Cherenkov telescopes as well as other high-speed optical astronomy. This work presents the opportunities and challenges of using EBCs in those cases, and proposes a low-cost approach to experimentally assess the feasibility of this innovative technique

Throughput and fairness of multiple TCP connections in wireless networks

TCP suffers from poor throughput performance in wireless networks. Furthermore, when multiple TCP connections compete at the base station, link errors and congestion lead to serious unfairness among the connections. Although the issue of TCP performance in wireless networks has attracted significant attention, most reports focus only on TCP throughput and assume that there is only a single connection in a congestion-free network. This paper studies the throughput and fairness of popular improvement mechanisms (the Snoop [8] and ELN [5]) and TCP variants with multiple TCP connections. Simulation results show that the improvement mechanisms under investigation are effective to improve TCP throughput in a wireless network. However, they cannot provide fairness among multiple TCP connections. From the studies presented, it is concluded that mechanisms to enhance TCP fairness are needed in wireless network

Leaving or Staying: Inter-Provincial Migration in Vietnam

Internal migration has several policy implications for economic growth and development for developing countries in general and for the fast growing low-income country of Vietnam in particular. Little research has been done, however, on inter-provincial migration in Vietnam. This study makes two major contributions to the migration and development literature in terms of the datasets and policy-relevant estimation approach. It is the first paper to use the annual survey data on migration published by Vietnam’s General Statistics Office. This study also adopts a functional form to accommodate the flexibility of income’s elasticity. Income, together with urban unemployment rates, are endogenously estimated with instruments that prove to be strong and valid. The inclusion of policy-relevant variables provides empirical findings that can make migration policy in Vietnam better-informed. Specifically, Vietnamese migrants are influenced primarily by moving costs, expected income differentials, disparity in the quality of public services offered by provinces, and the demographic composition at destination and source. This paper’s findings provide new insight for migration policy options, and suggest that the government adopt a holistic policy approach to maximize the benefits and minimize the costs associated with internal migration

Channel Characterisation and Link Budget of MIMO Configuration in Near Field Magnetic Communication

Traditional radio communication has gained significantly from using multiple input and multiple output (MIMO) architecture in the system. Many wireless applications, such as wireless LAN and cellular network, have adopted this technology to improve their system performance. However, the effect of MIMO systems has not been investigated in the case of inductive near field short range communications. The purpose of this paper is to explore a new method for increasing the magnetic communication range using MIMO. Three system models includingMISO, SIMO and MIMO are proposed to characterize the number of transmitters and receivers to the link. These models have helped to extend not only the range but also the communication channel in NFMIC

Startup Rates, Economic Growth, and Entrepreneurship Quality: A Multilevel Model

Based on behavioral entrepreneurship and institutional theory, we build a conceptual framework that describes the nature of the relationship between startup rates and economic growth. Our model indicates that the effects of startup rates on economic growth are contingent on entrepreneurship quality that is characterized by innovativeness, high growth, and export orientation. Then we investigate what factors determine the quality of entrepreneurship. We presuppose that entrepreneurial behaviors including entrepreneurial motivation, opportunity recognition, and resource construction are crucial antecedents of entrepreneurship quality. The linkages between entrepreneurial behaviors and entrepreneurship quality are positively moderated by environment factors according to institutional theory. These macro factors include economic freedom, policy supportiveness, cultural openness, and social supportiveness. We draw implications for research as well as the policy community

The Impact of Human Capital on Entrepreneurship Quality and Quantity at the Aggregate Level

Based on human capital theory and entrepreneurship literature, we propose that a country’s capital profiles including education level, industry experience, entrepreneurial experience, and immigration experience are positively related to its entrepreneurship quality. On the contrary, we hypothesize that these four dimensions are negatively associated with the quantity of entrepreneurship. These hypotheses are empirically examined on a sample of 86 countries obtained from Global Entrepreneurship Monitor (GEM) and 1,858,444 participants in a 10-year period, from 2007 to 2016. We utilize the Generalized Estimating Equations (GEEs) for the main hypothesis testing and the Random Effects Model for robustness analysis. The findings support most of the hypotheses. We then discuss theoretical implications drawn from the study and provide suggestions for policy makers. Our paper emphasizes that the investment in human capital may not simultaneously result in both high entrepreneurship quality and high entrepreneurship quantity at the aggregate level

Evaluation Of Accurate Dietary Supplement Product Labeling

Herbal supplement sales in the U.S. increased by 7.5% between 2014 and 2015, from $6.441 billion to$6.922 billion, according to newly released data from the Nutrition Business Journal (NBJ). Dietary supplements and over-the-counter medications (OTC’s) do not have to be proven safe or effective before being sold to consumers like prescription medications. Under the Dietary Supplement Health and Education Act of 1994, manufacturers only have to prove their product causes no harm to consumers. Dietary supplement labels are not reliable, since they are not regulated. Without verification a consumer cannot be sure that what is stated on the label is what is actually in the bottle. Some dietary supplements are known to contain saw dusts, lead, pesticides, arsenic, glass particles, and insect parts. Consumer Reports found that an estimated 23,000 people every year end up in emergency rooms after taking supplements. A 2013 report from the Government Accountability Office (GAO) found that from 2008 through 2011, the FDA received 6,307 reports of health problems from dietary supplements, including 92 deaths, hundreds of lifethreatening conditions, and more than 1,000 serious injuries or illnesses. The GAO suggests that due to underreporting, the actual number of incidents may be much greater since there are not any concrete reporting policies for dietary supplements as they make their way to consumers and have the potential to cause many problems. They can be ineffective, contaminated with microbes or heavy metals, dangerously mislabeled, or intentionally spiked with illegal or prescription drugs. Shockingly, Consumer Reports also found that over 1,000 supplements have been found to contain prescription or experimental drugs. The specific aim of this study is to verify whether dietary supplements and OTC’s contain the amount of ingredients claimed on the label of a product by using ConsumerLab.com® and USP® verification systems. ConsumerLab.com® and the USP® are the leading providers of independent test results, which approve whether products are accurately labeled with the correct amount of active ingredients and whether they contain harmful ingredients.https://dune.une.edu/pharmprac_facpost/1006/thumbnail.jp

Calibration to Mitigate Near-Field Antennas Effects for a MIMO Radar Imaging System

A calibration method for a high-resolution hybrid MIMO turntable radar imaging system is presented. A line of small metal spheres is employed as a test pattern in the calibration process to measure the position shift caused by undesired antenna effects. The unwanted effects in the antenna near-field responses are analysed, modelled and significantly mitigated based on the symmetry and differences in the responses of the MIMO configuration