Ionospheric Studies with the Differential Doppler Technique

This report is essentially a review of the measurements related to the ionosphere utilizing the differential Doppler technique. A brief study of the theory is presented, in which the error incurred in measurements of ionospheric electron content, caused by the assumption of common-path propagation, is shown as a function of the zenith angle of observation for different values of the critical frequency foF2. Some measurements of electron densities, electron content, horizontal gradients, irregularities, and magnetic-storm effects are discussed. Comments are also made about the method of combining the differential Doppler with the Faraday rotation measurements to establish a necessary constant of integration in the measurements made with satellites. It is concluded that the differential Doppler technique, with harmonically related frequencies transmitted to or from rockets or satellites, can provide accurate information about the electron density or electron content of the medium, and that the knowledge of these quantities is valuable in understanding the morphology of the ionospheric processes

Use of Smart Rocks to Improve Rock Slope Design

For many states, rockfall presents risks of irreversible damage to motorists on highways and roads across the country. Assessing these hazards is difficult as it relies on highly empirical methods based on assumed and/or measured slope and terrain surfaces and rock parameters, which can predict unrealistic trajectories due to unreliable modeling inputs. Research undertaken at the University of New Hampshire over the last decade includes the development of Smart Rock (SR) sensors used to evaluate these events from the perspective of the falling rock. The latest SRs consist of 3D printed capsules 50.8 mm in length and 25.4 mm in diameter, equipped with a ±400 g and a ±16 g 3-axis accelerometer, a ±4000 dps high-rate gyroscope, an altimeter, and a temperature sensor. Approximately 80 field experiments conducted in New Hampshire and Vermont provided SR data on rockfall at 10 different sites with a wide range of topographies and geological conditions. Preliminary laboratory and modeling assessments were also undertaken to compare experimental trajectories with rockfall simulations using different coefficients of restitution. It was concluded that acceleration and rotational velocity data from the rock perspective present a high potential to expand rockfall understanding and modeling. Such broader description of rockfall movements can enhance input parameters in computer rockfall modeling, which often disregards rotational data in kinetic energy estimates and tends to predict overly conservative trajectories

Higher Harmonics in Non-Linear Vacuum from QED Effects Without Low Mass Intermediate Particles

We show that in the presence of a slowly rotating strong transverse magnetic field there is an infinite spectrum of harmonic wave functions $A_n$ due to the first order QED correction (in $\alpha^2$) given by the Euler-Heisenberg Lagrangian. The frequency shifts are integer multiples $\pm \omega_0 n$ of the magnetic field angular frequency rotation $\omega_0=2\pi\nu_m$ and the several modes $n$ are coupled to the nearest harmonics $n\pm 1$. This is a new effect due to QED vacuum fluctuations, not exploit before, that can explain, both qualitatively and quantatively, the recent experimental results of the PVLAS collaboration without the need of a low mass intermediate particle, hence dismiss the recent claim of the discovery of the axion. [Erratum: The PVLAS signal cannot be explained by this mechanism.]Comment: 4 pages, 1 figure; includes Erratum: The PVLAS signal cannot be explained by this mechanis

The piano works of Leopoldo Miguéz (1850-1902)

Brazilian composer Leopoldo Américo Miguéz (1850–1902) lived in the cosmopolitan city of Rio de Janeiro at a time when the prevailing cultural background of the aristocracy was still prominently European. His entire production consisted of thirty-eight works with opus numbers and few other works that have not yet been published, all of which were influenced by European romantic music traditions while demonstrating no strong connection with Brazilian local and popular culture. He wrote a small quantity of twelve piano works represented in ten opus numbers, one collection of pieces without opus number, and one unpublished piece. These are mostly in short forms such as mazurkas, nocturnes, and character pieces with suggestive titles in the manner of short piano works by Brahms, Chopin, Fauré, Grieg, Mendelssohn, Liszt, and Schumann. With few exceptions, no great significance has been attributed to his piano works throughout the written history of Brazilian music. This is partly due to the lingering effect of two lines of negative criticism published during and after his lifetime that hurt his reputation and turned him into an obscure and forgotten composer. One was regarding his symphonic works, which were heavily influenced by Wagner, Berlioz, and Liszt. The other was in the context of an enduring process of nationalization of Brazilian arts and a rupture from European influences in the beginning of the 20th century. The music of Miguéz fell greatly out of favor during this campaign, resulting in lasting damage to his name that has yet to be reversed. The purpose of this dissertation is to draw attention to his pianistic output, asserting its integrity, quality, and valuable contribution to the development of music in Brazil. Biographical information as well as in-depth musical analysis of each piano work are supplied in the course of the narrative. My hope is that by providing and disseminating this information, Leopoldo Miguéz will be better understood, accepted, and more often performed

Towards Universality in Automatic Freeway Incident Detection: A Calibration-Free Algorithm

Freeway automatic incident detection (AID) algorithms have been extensively investigated over the last forty years. A myriad of algorithms, covering a broad range of types in terms of complexity, data requirements, and efficiency have been published in the literature. However, a 2007 nationwide survey concluded that the implementation of AID algorithms in traffic management centers is still very limited. There are a few reasons for this discrepancy between the state-of-the-art and the state-of the-practice. First, current AID algorithms yield unacceptably high rates of false alarm when implemented in real-world. Second, the complexities involved in algorithm calibration require levels of efforts and diligence that may overburden Traffic Management Center (TMC) personnel. The main objective of this research was to develop a self-learning, transferable algorithm that requires no calibration. The dynamic thresholds of the proposed algorithm are based on historical data of traffic, thus accounting for variations of traffic throughout the day. Therefore, the novel approach is able to recognize recurrent congestion, thus greatly reducing the incidence of false alarms. In addition, the proposed method requires no human-intervention, which certainly encourages its implementation. The presented model was evaluated in a newly developed incident database, which contained forty incidents. The model performed better than the California, Minnesota, and Standard Normal Deviation algorithms

An Evaluation of Alternative Permissive Periods on Non-Coordinated Phase Performance in Coordinated Traffic Signal Systems

Currently, there are some concerns regarding coordinated-actuated traffic signal operations. First of all, there is no consistent nomenclature to describe coordination modes. Different traffic signal controller manufacturers use different terminologies and their terms are not necessarily meaningful or intuitive. Actually, one can find inconsistency in the terminology used even by a specific manufacturer just by trying to understand (or decipher) the manual. Secondly, and this might be just a consequence of the first concern, it seems that many traffic engineers and technicians are not aware of the particularities and differences among the coordination modes. The main purpose of this study was to investigate the main issues related to non-coordinated movements of coordinated-actuated traffic signals. A set of terms and definitions including permissive point and permissive period was proposed. Based on this terminology, three coordination modes were presented and their performances were evaluated for three different volume/capacity (v/c) ratios by using hardware-in-the-loop (HITL) simulation. Using average vehicle delay as the measure of effectiveness (MOE), statistical analyses indicated that for moderate v/c ratios (0.50), the three coordination modes did not perform differently. For lower v/c ratios, differences among the modes were observed. The results of this thesis research provides some guidance on the use of coordinated-actuated traffic signal operation by letting traffic engineers and professionals be aware of the various effects that different coordination modes might cause on the intersection performance