See a Sign? Make a Call

DOT staff and technology resources have the proven potential to help combat human trafficking if DOT employees know the indicators of human trafficking and how to cooperate with requests from agencies for information that can be derived from DOT assets. The Texas A&M Transportation Institute, NCHRP, and the Heart of Texas Human Trafficking Coalition will discuss the intersection of human trafficking with the transportation sector. Attendees will also learn the main components of human trafficking, the basic signs of human trafficking on DOT facilities, and resources to use in their own states

Planning for Pedestrians and Bicyclists During Construction Projects

This session will explore how the Texas Department of Transportation Waco District addressed pedestrian/bicyclist safety and mobility during a multi-year construction project along I-35. This presentation will demonstrate the value of online tools, field implementations, and data collection. Attendees will learn the value of assembling a stakeholder steering committee; counting pedestrian and bicyclists before, during, and after construction; effectively using pavement clings; and using a webpage dedicated to pedestrian/bicyclist updates

Roundabout Maintenance Manual

In recent years, roundabouts have been rapidly growing in popularity. As a result, many communities are installing them in their roadways; however, they are encountering difficulties in maintaining them. Uneducated workers can cause damage to roundabouts and to themselves, costing cities time and money. This project aims to create a guide for communities new to roundabouts in order to reduce damages and unnecessary maintenance costs. Data was gathered by determining the most common maintenance questions and problems along with what information was already available on roundabout maintenance. Next, agencies most experienced with roundabouts were surveyed on the best maintenance practices. The responses from interview subjects gave detailed information on winter maintenance, summer maintenance, pavement maintenance, and vehicle and pedestrian access during maintenance activities. The data was compiled to create the roundabout maintenance manual. The guide created from the data collection will be helpful for communities new to roundabouts and serve as a reference for agencies in Indiana and surrounding states. In future years, the methods established in this guide should be re-evaluated and updated

MTBE: Coverage For This Spreading Problem

Environmental professionals need to understand the legal issues involving MTBE-related claims and insurance coverage. Legal actions involving MTBE contamination are on the rise. Throughout the United States, litigation has included MTBE claims based on negligence, conspiracy, property damage and product liability. In April 2002, for example, after an 11–month trial brought by a California public utility against MTBE producers, oil refineries and gasoline retailers, a jury found that gasoline containing MTBE was a defective product and decided in favor of large awards to plaintiffs. As a possible harbinger of what is to come, a number of law firms now include information relating to MTBE on their websites. As MTBE–based claims increase, disputes concerning insurance coverage for those claims will also most assuredly increase. This presentation will provide a framework for helping to determine how insurance policies cover MTBE–related claims. For example, if government requirements to use MTBE result in legal actions relating to substances or commercial products exempted from Superfund liability, can insurance companies successfully deny coverage based on a pollution exclusion? Standard liability insurance forms generally provide coverage for damage to the environment arising from MTBE. First, the large majority of jurisdictions that have addressed the issue of the “legal obligation to pay” hold that amounts paid to address government mandates in administrative enforcement actions are amounts which the policyholder “is legally obligated to pay as damages.” Therefore, costs to investigate and remediate MTBE contamination in response to a government directive should be construed “as damages” which a policyholder is legally obligated to pay. Second, environmental contamination arising from gasoline containing MTBE is “property damage” and courts uniformly hold so. Such damage generally is to the property of a third–party because most states designate groundwater as a resource held in trust for all people so actual or potential threats to groundwater from MTBE are considered damage to the property of another. Third, “property damage” takes place or “triggers” coverage as long as the gasoline spill or leak was released into the environment at least, in part, during the policy period(s) at issue. To deny insurance coverage for MTBE–related environmental damages, the insurance companies have (with varying degrees of success) relied upon: (1) the “expected or intended”/no “occurrence” defense; and (2) various forms of “pollution” exclusions. Policyholders should be sure this fine print actually applies before taking “no coverage” for an answer. While coverage for MTBE–related liabilities will not come easily, policyholders and environmental professionals need to know what evidence is necessary to support a claim for MTBE coverage

Changes in Traffic Patterns and Air Quality Along Mystic Avenue in Medford and Somerville, Massachusetts, After Installation of an Intermittent Bus Lane

The City of Medford, MA, (pop. 60,000) and the City of Somerville (pop. 76,000) immediately to the south are home to several major roadways including Interstate 93 and Massachusetts State Highways 28 and 38. These are among the busiest roadways in the Boston metropolitan area, together carrying over 240,000 vehicles per day through the two cities (Boston MPO, 2022). In an effort to increase bus efficiency, reduce traffic burden, and improve air quality in their communities, Medford and Somerville tested a bus lane with intermittent prioritization on Massachusetts Bay Transportation Authority (MBTA) bus route #95, which runs along Route 38 (Mystic Avenue) within the two cities.The goal of this study was to determine whether the bus lane on Mystic Avenue caused short term (months) changes in traffic patterns and improved air quality along the length of the bus lane

Coherent Umklapp Scattering of Light from Disordered Photonic Crystals

A theoretical study of the coherent light scattering from disordered photonic crystal is presented. In addition to the conventional enhancement of the reflected light intensity into the backscattering direction, the so called coherent backscattering (CBS), the periodic modulation of the dielectric function in photonic crystals gives rise to a qualitatively new effect: enhancement of the reflected light intensity in directions different from the backscattering direction. These additional coherent scattering processes, dubbed here {\em umklapp scattering} (CUS), result in peaks, which are most pronounced when the incident light beam enters the sample at an angle close to the the Bragg angle. Assuming that the dielectric function modulation is weak, we study the shape of the CUS peaks for different relative lengths of the modulation-induced Bragg attenuation compared to disorder-induced mean free path. We show that when the Bragg length increases, then the CBS peak assumes its conventional shape, whereas the CUS peak rapidly diminishes in amplitude. We also study the suppression of the CUS peak upon the departure of the incident beam from Bragg resonance: we found that the diminishing of the CUS intensity is accompanied by substantial broadening. In addition, the peak becomes asymmetric.Comment: LaTeX, 8 two-column pages, 6 figures include

Foundation Design for High Tension Cable Guardrails

High tension cable guardrail is becoming increasing popular in median and roadside applications due to the promise of reduced deflections upon impact and reduced maintenance. As the performance of these systems is observed in service, there is a growing concern over the end anchorage foundation performance of current systems. Foundations for high tension systems must not only be capable of restraining the impact load of a vehicle but must also restrain the initial pretension on the cable system as well as temperature induced loads. While it may be acceptable for many roadside safety devices to require foundation repair after impact, foundation failure due to environmentally induced loads would be a serious maintenance problem. As initial tension and temperature induced loads can be greater than those loads applied during impact, this type of loading must be considered in foundation design. Foundation deflection can reduce cable tension, increasing deflection of the system during impact and letting the cables sag after impact. The soil conditions in which these foundations are placed vary significantly. This report considers the potential impact, tension, and temperature loads and develops a set of suggested foundation designs to accommodate a range of in situ soil conditions. These designs will vary significantly in different areas around the nation due to variations in both weather and in situ soil conditions. Deflection during full-scale crash tests may not accurately represent the foundation deflection that will be experienced in the field

Erratum: effects of lattice geometry and interaction range on polaron dynamics

Erratum: effects of lattice geometry and interaction range on polaron dynamic

Superlight small bipolarons in the presence of strong Coulomb repulsion

We study a lattice bipolaron on a staggered triangular ladder and triangular and hexagonal lattices with both long-range electron-phonon interaction and strong Coulomb repulsion using a novel continuous-time quantum Monte-Carlo (CTQMC) algorithm extended to the Coulomb-Frohlich model with two particles. The algorithm is preceded by an exact integration over phonon degrees of freedom, and as such is extremely efficient. The bipolaron effective mass and bipolaron radius are computed. Lattice bipolarons on such lattices have a novel crablike motion, and are small but very light in a wide range of parameters, which leads to a high Bose-Einstein condensation temperature. We discuss the relevance of our results with current experiments on cuprate high-temperature superconductors and propose a route to room temperature superconductivity