Modeling and Design of Millimeter-Wave Networks for Highway Vehicular Communication

Connected and autonomous vehicles will play a pivotal role in future Intelligent Transportation Systems (ITSs) and smart cities, in general. High-speed and low-latency wireless communication links will allow municipalities to warn vehicles against safety hazards, as well as support cloud-driving solutions to drastically reduce traffic jams and air pollution. To achieve these goals, vehicles need to be equipped with a wide range of sensors generating and exchanging high rate data streams. Recently, millimeter wave (mmWave) techniques have been introduced as a means of fulfilling such high data rate requirements. In this paper, we model a highway communication network and characterize its fundamental link budget metrics. In particular, we specifically consider a network where vehicles are served by mmWave Base Stations (BSs) deployed alongside the road. To evaluate our highway network, we develop a new theoretical model that accounts for a typical scenario where heavy vehicles (such as buses and lorries) in slow lanes obstruct Line-of-Sight (LOS) paths of vehicles in fast lanes and, hence, act as blockages. Using tools from stochastic geometry, we derive approximations for the Signal-to-Interference-plus-Noise Ratio (SINR) outage probability, as well as the probability that a user achieves a target communication rate (rate coverage probability). Our analysis provides new design insights for mmWave highway communication networks. In considered highway scenarios, we show that reducing the horizontal beamwidth from $90^\circ$ to $30^\circ$ determines a minimal reduction in the SINR outage probability (namely, $4 \cdot 10^{-2}$ at maximum). Also, unlike bi-dimensional mmWave cellular networks, for small BS densities (namely, one BS every $500$ m) it is still possible to achieve an SINR outage probability smaller than $0.2$.Comment: Accepted for publication in IEEE Transactions on Vehicular Technology -- Connected Vehicles Serie

Ridge Vent and Wind Direction Effects on Airflow Characteristics in a Model Open Front Beef Building

Ridge vent design and building orientation with respect to predominating winds are two primary factors influencing the effectiveness of natural ventilation. Research concerning ridge vent design and building orientation as a means of optimizing natural ventilation is inconclusive and incomplete. Therefore, a model study was conducted to study ventilation characteristics of a model open front beef confinement unit with the following objective: 1) Evaluate the effects of ridge vent design and wind direction on air flow characteristics and temperature in a model of an open front beef building. 2) Develop prediction equations for the relationship between wind velocity and outlet velocity in a model of an open front beef building. 3) Develop prediction equations for the relationship between wind velocity and temperature difference in a model of an open front building

Pupil slicer design for the NASA-NSF extreme precision Doppler spectrograph concept WISDOM

The WIYN Spectrograph for Doppler Monitoring (WISDOM) was a concept responding to NASA's solicitation for an extreme precision radial velocity instrument for the 3.5 meter WIYN telescope on Kitt Peak in Arizona. In order to meet the spectral resolution requirement of R = 110,000 while maintaining good throughput and a manageable beam diameter, the front end design of the instrument employed a pupil slicing technique wherein a collimated beam is sliced and fed to six separate fibers. This paper presents the optical and mechanical design of the pupil slicer subassembly, a unique method of dealing with thermally induced defocus error, and the methods and results of aligning a prototype

Precarious entitlement to public space and utility cycling in Dublin: a grounded theory study

Reports on the safety of cycling and research investigating factors thought to impinge on cycling risk and safety are often complex, insufficient and, at times, contradictory and inconclusive. Amongst this ambiguous understanding of matters of risk and safety in relation to cycling, the provisional aim of this study was to explore how cyclists themselves deal with matters of risk in the context of Dublin. Classical grounded theory methodology was employed over the course of the study. Data collection involved 28 qualitative interviews which took place simultaneously with data analysis, in which grounded theory procedures were adhered to; namely, open coding, selective coding, memoing, theoretical sampling, and theoretical saturation. Emerging from data collection and analysis, it was conceptualised that dealing with conditions of ‘precarious entitlement’ to public space is a main concern of utility cyclists in Dublin. That is, cyclists in Dublin perceive an entitlement to public space that is precarious to exercise as a cyclist in practice. In order to negotiate such conditions, cyclists in Dublin can engage in ‘privatising vulnerability’. Namely, they can make their vulnerability a matter of personal rather than shared responsibility, prioritising their perceived safety over matters of entitlement, responsibility and fairness through particular modes of action. Furthermore, cyclists in Dublin can engage in practices of ‘provoking responsibility’, in which both subtle and conspicuous actions are taken in order to provoke a sense of responsibility in other public space users to respect a cyclist’s entitlement to public space and vulnerability within conditions of precarious entitlement. This theory reveals a new form of structural vulnerability, a ‘state of nature within a state of civilisation’ and a problem of accessibility to public space. Moreover, it conceptualises modes of action in an urban context that involve social withdrawal, submission, and individualisation in public space, as well as active and ongoing negotiation between citizens of life in common and recognition, alongside efforts to appropriate and produce public space

Towards a Synthetic Account of Sin that Merges Magisterial Teaching and Theological Reflection on Sin with the Philosophical Insights of Bernard J.F. Lonergan

In my dissertation I shall develop a synthetic account of sin that examines and takes seriously the theological anthropology provided by the magisterium and contemporary theologians. I shall also attempt to make this account of sin accessible to the more sceptical reader by drawing on the work of the Canadian philosopher and theologian Bernard Lonergan (1904-84). In his works, especially Insight (1957), Lonergan provides solid foundations for the possibility of sin, ethical knowledge, and human freedom

Cost effectiveness of a general practice chronic disease management plan for coronary heart disease in Australia

Background. The cost effectiveness of a general practice-based program for managing coronary heart disease (CHD) patients in Australia remains uncertain. We have explored this through an economic model.Methods. A secondary prevention program based on initial clinical assessment and 3 monthly review, optimising of pharmacotherapies and lifestyle modification, supported by a disease registry and financial incentives for quality of care and outcomes achieved was assessed in terms of incremental cost effectiveness ratio (ICER), in Australian dollars per disability adjusted life year (DALY) prevented.Results. Based on 2006 estimates, 263 487 DALYs were attributable to CHD in Australia. The proposed program would add $115 650 000 to the annual national heath expenditure. Using an estimated 15$8081 per DALY prevented. With more conservative estimates of effectiveness and uptake, estimates of up to $38 316 per DALY are observed in sensitivity analysis.Conclusions. Although innovation in CHD management promises improved future patient outcomes, many therapies and strategies proven to reduce morbidity and mortality are available today. A general practice-based program for the optimal application of current therapies is likely to be cost-effective and provide substantial and sustainable benefits to the Australian community.What is known about this topic? Chronic disease management programs are known to provide gains with respect to reductions in death and disability among patients with coronary heart disease. The cost effectiveness of such programs in the Australian context is not known.What does this paper add? This paper suggests that implementing a coronary heart disease program in Australia is highly cost-effective across a broad range of assumptions of uptake and effectiveness.What are the implications for practitioners? These data provide the economic rationale for the implementation of a chronic disease management program with a disease registry and regular review in Australia

Diversity, Equity, and Inclusion-centered OER creation: A collaboration across six public higher education institutions

This panel will speak to the unique structure of the multi-year, multi-institutional Textbook Success Pilot program in Massachusetts: Remixing Open Textbooks through an Equity Lens (ROTEL): Culturally Relevant Open Textbooks for High Enrollment General Education Courses and Career and Professional Courses at Six Public Massachusetts Colleges. Panelists with multiple perspectives will discuss the many moving parts to achieve an ambitious goal of adapting and creating 72 open textbooks within three years. OER users of all levels (beginner, intermediate, advanced) are welcome. We will begin by giving a brief overview of the grant project, our infrastructure, and our process for establishing cultural and marketplace relevance as a core component of our content creation. Panelists will speak to the professional development partnerships we have made with Rebus, acquisition of the Pressbooks Content Management System (CMS), construction of an Industry Advisory Board, and our goals in alignment with the COUP framework (Cost, Outcomes, Usage, Perceptions). Panelists will also take a deep dive into the uniqueness of this grant work: centering equity, diversity, and inclusion; building support teams across six institutions; and prioritizing accessibility. We will share the Key Performance Indicators developed for this project and their importance to assessing impact using a COUP Framework (i.e., Cost, Outcome, Usage, and Perceptions). Attendees will participate in an interactive activity to reflect on potential opportunities for OER at each individual institution

A concept for seeing-limited near-IR spectroscopy on the Giant Magellan Telescope

We present a simple seeing-limited IR spectrometer design for the Giant Magellan Telescope, with continuous R = 6000 coverage from 0.87-2.50 microns for a 0:7” slit. The instrument's design is based on an asymmetric white pupil echelle layout, with dichroics splitting the optical train into yJ, H, and K channels after the pupil transfer mirror. A separate low-dispersion mode offers single-object R ~ 850 spectra which also cover the full NIR bandpass in each exposure. Catalog gratings and H2RG detectors are used to minimize cost, and only two cryogenic rotary mechanisms are employed, reducing mechanical complexity. The instrument dewar occupies an envelope of 1:8×1:5×1:2 meters, satisfying mass and volume requirements for GMT with comfortable margin. We estimate the system throughput at ~ 35% including losses from the atmosphere, telescope, and instrument (i.e. all coatings, gratings, and sensors). This optical efficiency is comparable to the FIRE spectrograph on Magellan, and we have specified and designed fast cameras so the GMT instrument will have an almost identical pixel scale as FIRE. On the 6.5 meter Magellan telescopes, FIRE is read-noise limited in the y and J bands, similar to other existing near-IR spectrometers and also to JWST/NIRSPEC. GMT's twelve-fold increase in collecting area will therefore offer gains in signal-to-noise per exposure that exceed those of moderate resolution optical instruments, which are already sky-noise limited on today's telescopes. Such an instrument would allow GMT to pursue key early science programs on the Epoch of Reionization, galaxy formation, transient astronomy, and obscured star formation environments prior to commissioning of its adaptive optics system. This design study demonstrates the feasibility of developing relatively affordable spectrometers at the ELT scale, in response to the pressures of joint funding for these telescopes and their associated instrument suites.Massachusetts Institute of Technology. Department of Physics.Kavli Institute for Astrophysics and Space Researc

Circumstellar Structure around Evolved Stars in the Cygnus-X Star Formation Region

We present observations of newly discovered 24 micron circumstellar structures detected with the Multiband Imaging Photometer for Spitzer (MIPS) around three evolved stars in the Cygnus-X star forming region. One of the objects, BD+43 3710, has a bipolar nebula, possibly due to an outflow or a torus of material. A second, HBHA 4202-22, a Wolf-Rayet candidate, shows a circular shell of 24 micron emission suggestive of either a limb-brightened shell or disk seen face-on. No diffuse emission was detected around either of these two objects in the Spitzer 3.6-8 micron Infrared Array Camera (IRAC) bands. The third object is the luminous blue variable candidate G79.29+0.46. We resolved the previously known inner ring in all four IRAC bands. The 24 micron emission from the inner ring extends ~1.2 arcmin beyond the shorter wavelength emission, well beyond what can be attributed to the difference in resolutions between MIPS and IRAC. Additionally, we have discovered an outer ring of 24 micron emission, possibly due to an earlier episode of mass loss. For the two shell stars, we present the results of radiative transfer models, constraining the stellar and dust shell parameters. The shells are composed of amorphous carbon grains, plus polycyclic aromatic hydrocarbons in the case of G79.29+0.46. Both G79.29+0.46 and HBHA 4202-22 lie behind the main Cygnus-X cloud. Although G79.29+0.46 may simply be on the far side of the cloud, HBHA 4202-22 is unrelated to the Cygnus-X star formation region.Comment: Accepted by A