Simulating Vehicle Movement and Multi-Hop Connectivity from Basic Safety Messages

The Basic Safety Message (BSM) is a standardized communication packet that is sent every tenth of a second between connected vehicles using Dedicated Short Range Communication (DSRC). BSMs contain data about the sending vehicle's state, such as speed, location, and the status of the turn signal. Currently, many BSM datasets are available through the connected vehicle testbeds of U.S. Department of Transportation from all over the country. However, without a proper visualization tool, it is not possible to analyze or visually get an overview of the spatio-temporal distribution of the data. With this goal, a web application has been developed which can ingest a raw BSM dataset and display a time-based simulation of vehicle movement. The simulation also displays multi-hop vehicular network connectivity over DSRC. This paper gives details about the application, including an explanation of the multi-hop partitioning algorithm used to classify the vehicles into separate network partitions. A performance analysis for the simulation is included, in which it is suggested that calculating a connectivity matrix with the multi-hop partitioning algorithm is computationally expensive for large number of vehicles

Simulation of a Channel with Another Channel

In this paper, we study the problem of simulating a DMC channel from another DMC channel under an average-case and an exact model. We present several achievability and infeasibility results, with tight characterizations in special cases. In particular for the exact model, we fully characterize when a BSC channel can be simulated from a BEC channel when there is no shared randomness. We also provide infeasibility and achievability results for simulation of a binary channel from another binary channel in the case of no shared randomness. To do this, we use properties of R\'enyi capacity of a given order. We also introduce a notion of "channel diameter" which is shown to be additive and satisfy a data processing inequality.Comment: 31 pages, 10 figures, and some parts of this work were published at ITW 201

AC Electrokinetic Effect of V-Electrode Pattern on Microfluids

Electrokinetics has been used for guiding, pumping, and manipulating microfluidic particles for many years in the field of Biomedical, Microbiology, Chemistry, Medicine, and other fields of research, which makes it a ubiquitous tool for the multidisciplinary research on microfluidics. Between these two Alternating Current (AC) Electrokinetics have been proven to be more feasible for the researcher than the other one. In this research, we have investigated AC Electrokinetics and s effect on a new electrode configuration called V-electrode pattern. The V-electrode has been inspired and modified from the previous research work on the Orthogonal Electrode Pattern. In this research, this new electrode configuration has been analyzed using different types of setups, fabrication methods, and different fluidic conditions

Communication-Aware Computing for Edge Processing

We consider a mobile edge computing problem, in which mobile users offload their computation tasks to computing nodes (e.g., base stations) at the network edge. The edge nodes compute the requested functions and communicate the computed results to the users via wireless links. For this problem, we propose a Universal Coded Edge Computing (UCEC) scheme for linear functions to simultaneously minimize the load of computation at the edge nodes, and maximize the physical-layer communication efficiency towards the mobile users. In the proposed UCEC scheme, edge nodes create coded inputs of the users, from which they compute coded output results. Then, the edge nodes utilize the computed coded results to create communication messages that zero-force all the interference signals over the air at each user. Specifically, the proposed scheme is universal since the coded computations performed at the edge nodes are oblivious of the channel states during the communication process from the edge nodes to the users.Comment: To Appear in ISIT 201

THE PROPAGATION AND EVOLUTION OF CORONAL MASS EJECTION DRIVEN SHEATH REGIONS: INSIGHT FROM MULTI-SPACECRAFT MEASUREMENTS AND STATISTICAL APPROACHES

The complexities of our nearest star, the Sun, are characterized by its magnetic field. In the absence of a magnetic field, diverse phenomena as the solar cycle, solar eruptions, solar wind, to name but a few, would be unknown to us. Coronal mass ejections, a large form of solar eruption, are an essential mechanism for the evolution of the Sun. CMEs provide a means by which the built-up magnetic flux and solar material over solar cycles are removed from the solar atmosphere into the solar wind. This spectacular phenomenon has repercussions throughout the heliosphere, driving a range of heliospheric, magnetospheric, ionospheric, atmospheric, and ground effects, collectively called space weather. Each CME structure (shock, sheath, and magnetic ejecta) has distinctive characteristics, but all cause perturbations on different scales within regular solar wind conditions. CME-driven shock is the discontinuous transition from a supersonic (or more accurately faster than the fast magnetosonic speed) to a subsonic (or more accurately slower than the fast magnetosonic speed) solar wind, and the sheath is the region of compressed and heated solar wind plasma with higherpower of magnetic field fluctuations. In contrast, the magnetic ejecta is a magnetically-dominated region of lower proton density and kinetic temperature with minimal magnetic field fluctuations. In this thesis, the characteristics and radial evolution of CME sheaths are investigated with multi-spacecraft observations in the inner heliosphere and single-spacecraft measurements near 1 astronomical unit (AU, the mean distance from the center of the Earth to the center of the Sun). In general, the radial evolution of CMEs is inferred from analyzing different CMEs at different heliospheric distances from the Sun. Such statistical approaches are hindered by the inhomogeneity of CMEs, leading to uncertain estimates. The results presented in this thesis provide observational evidence of the inhomogeneity of CME structures. Especially as the heliocentric distance increases, the exponential decrease of the magnetic field strength within the sheath has less CME-to-CME variability than the CME. The results also indicatethat CME expansion near 1 AU does not reflect its expansion in the innermost heliosphere. However, multi-spacecraft observations can also lead to an erroneous treatment of the radial evolution. Our findings suggest that the primary sources of uncertainties in multi-spacecraft observations are longitudinal separations between the measuring spacecraft. This thesis sheds new light on the physical processes responsible for the observed variabilities of CME sheaths near-Earth. The results point towards the hypothesis that such observed variabilities of CME sheaths near 1 AU are likely to be governed by the sheath formation mechanisms and intrinsic CME characteristics. One fascinating aspect of our findings is that sheath variabilities tend to be not influenced by the shocks that precede them. On the other hand, preliminary statistics from our threshold-based probabilistic forecasting model demonstrate the importance of shocks, hinting at the solar wind variations in the vicinity of shocks to be a strong indicator of an upcoming intense and prolonged southward magnetic field period