Generalized Weyl solutions

It was shown by Weyl that the general static axisymmetric solution of the vacuum Einstein equations in four dimensions is given in terms of a single axisymmetric solution of the Laplace equation in three-dimensional flat space. Weyls construction is generalized here to arbitrary dimension D>~4. The general solution of the D-dimensional vacuum Einstein equations that admits D-2 orthogonal commuting non-null Killing vector fields is given either in terms of D-3 independent axisymmetric solutions of Laplaces equation in three-dimensional flat space or by D-4 independent solutions of Laplaces equation in two-dimensional flat space. Explicit examples of new solutions are given. These include a five-dimensional asymptotically flat black ring with an event horizon of topology S1S2 held in equilibrium by a conical singularity in the form of a disk.

Finite energy Dirac-Born-Infeld monopoles and string junctions

It is shown that the world volume field theory of a single D3-brane in a supergravity D3-brane background admits finite energy, and non-singular, Abelian monopoles and dyons preserving 1/2 or 1/4 of the N=4 supersymmetry and saturating a Bogomolnyi-type bound. The 1/4 supersymmetric solitons provide a world volume realization of string-junction dyons. We also discuss the dual M-theory realization of the 1/2 supersymmetric dyons as finite tension self-dual strings on the M5-brane, and of the 1/4 supersymmetric dyons as their intersections.

Cosmic strings and Einstein-Rosen soliton waves

We consider all generalized soliton solutions of the Einstein-Rosen form in the cylindrical context. They are Petrov type-I solutions which describe solitonlike waves interacting with a line source placed on the symmetry axis. Some of the solutions develop a curvature singularity on the axis which is typical of massive line sources, whereas others just have the conical singularity revealing the presence of a static cosmic string. The analysis is based on the asymptotic behavior of the Riemann and metric tensors, the deficit angle, and a C-velocity associated to Thornes C-energy. The C-energy is found to be radiated along the null directions.

Engineering Study Iowa Highway Resarch Board Project HR-223 Maintaining Granular Surfaced Roads, February 1981

Approximately 65% of Iowa's roads are surfaced with aggregates composed of crushed limestone and/or gravel. Rural Iowan's regard these roads as a very important part of their lives. Therefore, the slide-tape presentation, "Maintaining Granular Surfaced Roads" was developed to aid the motor grader operator to better understand the procedures required t o maintain aggregate surfaced roads. A typical cross-section is presented with the proper nomenclature assigned to the roadway features to facilitate the operator's understanding of the basic terms used the program. The following areas are expanded: safety , dragging, cutting, intersections , superelevations, and reporting any discrepancies. The operator's attention to detail can enhance the economy of the state and contribute to the savings of lives on rural highways.

Evaluating the Effectiveness of Red Light Running Camera Enforcement in Cedar Rapids and Developing Guidelines for Selection and Use of Red Light Running Countermeasures Final Report, November 2011

Red light running (RLR) is a problem in the US that has resulted in 165,000 injuries and 907 fatalities annually. In Iowa, RLR-related crashes make up 24.5 percent of all crashes and account for 31.7 percent of fatal and major injury crashes at signalized intersections. RLR crashes are a safety concern due to the increased likelihood of injury compared to other types of crashes. One tool used to combat red light running is automated enforcement in the form of RLR cameras. Automated enforcement, while effective, is often controversial. Cedar Rapids, Iowa installed RLR and speeding cameras at seven intersections across the city. The intersections were chosen based on crash rates and whether cameras could feasibly be placed at the intersection approaches. The cameras were placed starting in February 2010 with the last one becoming operational in December 2010. An analysis of the effect of the cameras on safety at these intersections was determined prudent in helping to justify the installation and effectiveness of the cameras. The objective of this research was to assess the safety effectiveness of the RLR program that has been implemented in Cedar Rapids. This was accomplished by analyzing data to determine changes in the following metrics:  Reductions in red light violation rates based on overall changes, time of day changes, and changes by lane  Effectiveness of the cameras over time  Time in which those running the red light enter the intersection  Changes in the average headway between vehicles entering the intersection

Toolbox of Countermeasures to Reduce Red Light Running Final Report, April 2012

Red light running (RLR) is a problem in the US that has resulted in 165,000 injuries and 907 fatalities annually. In Iowa, RLR-related crashes make up 24.5 percent of all crashes and account for 31.7 percent of fatal and major injury crashes at signalized intersections. RLR crashes are a safety concern due to the increased likelihood of injury compared to other types of crashes. The research team developed this toolbox for practitioners to address RLR crashes. The Four Es—Engineering, Enforcement, Education, and Emergency Response—should be used together to address RLR problems. However, this toolbox focuses on engineering, enforcement, and education solutions. The toolbox has two major parts:  Guidelines to identify problem intersections and the causes of RLR at intersections  Roadway-based and enforcement countermeasures for RLR

Roadway Lighting and Safety: Phase II – Monitoring Quality, Durability and Efficiency, November 2011

This Phase II project follows a previous project titled Strategies to Address Nighttime Crashes at Rural, Unsignalized Intersections. Based on the results of the previous study, the Iowa Highway Research Board (IHRB) indicated interest in pursuing further research to address the quality of lighting, rather than just the presence of light, with respect to safety. The research team supplemented the literature review from the previous study, specifically addressing lighting level in terms of measurement, the relationship between light levels and safety, and lamp durability and efficiency. The Center for Transportation Research and Education (CTRE) teamed with a national research leader in roadway lighting, Virginia Tech Transportation Institute (VTTI) to collect the data. An integral instrument to the data collection efforts was the creation of the Roadway Monitoring System (RMS). The RMS allowed the research team to collect lighting data and approach information for each rural intersection identified in the previous phase. After data cleanup, the final data set contained illuminance data for 101 lighted intersections (of 137 lighted intersections in the first study). Data analysis included a robust statistical analysis based on Bayesian techniques. Average illuminance, average glare, and average uniformity ratio values were used to classify quality of lighting at the intersections.

Road Safety Audit for the Intersection of US 59 and IA 9 in Osceola County, Iowa Final Report, March 2012

The Iowa Department of Transportation (DOT) requested a road safety audit (RSA) of the US 59/IA 9 intersection in northwestern Iowa, just south of the Minnesota border, to assess intersection environmental issues and crash history and recommend appropriate mitigation to address the identified safety issues at the intersection. Although the number of crashes at the location has not been significantly higher than the statewide average for similar intersections, the severity of these crashes has been of concern. This RSA was unique in that it included intersection video observation and recorded traffic conflict data analysis, along with the daylight and nighttime field reviews. This report outlines the findings and recommendations of the RSA team for addressing the safety concerns at this intersection.

Sequential decisions in allocation problems

[eng] In the context of cooperative TU-games, and given an order of players, we consider the problem of distributing the worth of the grand coalition as a sequentia decision problem. In each step of process, upper and lower bounds for the payoff of the players are required related to successive reduced games. Sequentially compatible payoffs are defined as those allocation vectors that meet these recursive bounds. The core of the game is reinterpreted as a set of sequentally compatible payoffs when the Davis-Maschler reduced game is considered (Th.1). Independently of the reduction, the core turns out to be the intersections of the family of the sets of sequentially compatible payoffs corresponding to the different possible orderings (Th.2), so it is in some sense order-independent. Finally, we analyze advantagenous properties for the first player

Rural Expressway Intersection Safety Toolbox Desktop Reference, June 17, 2011

This document is intended to be a guide for planning-level decisions concerning safety issues and subsequent potential improvements at rural expressway intersections. It is NOT a design guide. It simply presents the gamut of safety treatment options and available strategies that have been employed in an attempt to reduce the number and severity of collisions at unsignalized rural expressway intersections.

Environmental Assessment: IA 12 in Mason City From S. Monroe Ave to S. Carolina Ave, Cerro Gordo County, Iowa, NHSX-122-1(14)--3H-17, 2013

DESCRIPTION OF PROPOSED ACTION This Environmental Assessment (EA) has been prepared in compliance with the requirements of the National Environmental Policy Act of 1969 (NEPA). This EA informs the public and interested agencies of the proposed action and alternatives to the proposed action in order to gather feedback on the improvements under consideration. Proposed Action The Iowa Department of Transportation (Iowa DOT) and the Federal Highway Administration (FHWA) are evaluating potential alternatives to improve IA 122 in the City of Mason City. IA 122/Business US 18 is a primary east-west travel route through the City that transitions from a 4- lane undivided roadway, to 2-lane one-way pairs, then back to a 4-lane undivided roadway (Figure 1-1). The Iowa DOT proposes to flatten the tight reverse curves on the east end of the project. The one-way pairs will be narrowed by eliminating on-street parking along the corridor to more clearly define travel lanes. This will serve to calm traffic flows and reduce crashes along the highway. Additionally, improvements to intersections as well as consolidating or removing access points to improve traffic operations are proposed within the project corridor. A new access road for the Mason City Fire Department on the west end of the project will allow emergency trucks better access to travel south and east. Study Area The primary area of investigation for the Project is generally bounded by IA 122 through Mason City, known locally as 5th and 6th Street Southwest from South Monroe Avenue to South Carolina Avenue. US 65, known locally as Federal Avenue, bisects the study area. At this intersection of US 65 and Iowa 122, the 5th and 6th Street SW changes to 5th and 6th St SE. For the purposes of this discussion, this area will be referred to collectively as the IA 122 corridor. The Study Area boundaries were established to allow the development of a wide range of alternatives that could address the purpose and need for the project. The Study Area is larger than the area proposed for construction activities for the Project. However, some impacts may extend beyond the Study Area; where this occurs, it will be noted and addressed in the Environmental Analysis Section (Section 5). Figure 1-1 outlines the Study Area of the proposed action.

Una nova subespàcie de Pedicularis pyrenaica J. Gay (Scrophulariaceae) als Pirineus Centrals

A new subspecies of Pedicularis pyrenaica J. Gay (Scrophulariaceae) in Central Pyrenees. We describe a new subspecies of Pedicularis pyrenaica (P. pyrenaica subsp. praetermissa) from the Central Pyrenees, which differs from the typical in the shape of the upper lip of the corolla (fusiform, attenuated in a conical beak), as for the larger size of the corolla and the whole plant. We add several comments on the morphological characterization and the habitat of the plant in relation to close taxa

Examination of Heterogeneous Crossing Sequences Between Toner and Rollerball Pen Strokes by Digital Microscopy and 3-D Laser Profilometry

The determination of line crossing sequences between rollerball pens and laser printers presents difficulties that may not be overcome using traditional techniques. This research aimed to study the potential of digital microscopy and 3-D laser profilometry to determine line crossing sequences between a toner and an aqueous ink line. Different paper types, rollerball pens, and writing pressure were tested. Correct opinions of the sequence were given for all case scenarios, using both techniques. When the toner was printed before the ink, a light reflection was observed in all crossing specimens, while this was never observed in the other sequence types. The 3-D laser profilometry, more time-consuming, presented the main advantage of providing quantitative results. The findings confirm the potential of the 3-D laser profilometry and demonstrate the efficiency of digital microscopy as a new technique for determining the sequence of line crossings involving rollerball pen ink and toner. With the mass marketing of laser printers and the popularity of rollerball pens, the determination of line crossing sequences between such instruments is encountered by forensic document examiners. This type of crossing presents difficulties with optical microscopic line crossing techniques involving ballpoint pens or gel pens and toner (1-4). Indeed, the rollerball's aqueous ink penetrates through the toner and is absorbed by the fibers of the paper, leaving the examiner with the impression that the toner is above the ink even when it is not (5). Novotny and Westwood (3) investigated the possibility of determining aqueous ink and toner crossing sequences by microscopic observation of the intersection before and after toner removal. A major disadvantage of their study resides in destruction of the sample by scraping off the toner line to see what was underneath. The aim of this research was to investigate the ways to overcome these difficulties through digital microscopy and three-dimensional (3-D) laser profilometry. The former was used as a technique for the determination of sequences between gel pen and toner printing strokes, but provided less conclusive results than that of an optical stereomicroscope (4). 3-D laser profilometry, which allows one to observe and measure the topography of a surface, has been the subject of a number of recent studies in this area. Berx and De Kinder (6) and Schirripa Spagnolo (7,8) have tested the application of laser profilometry to determine the sequence of intersections of several lines. The results obtained in these studies overcome disadvantages of other methods applied in this area, such as scanning electron microscope or the atomic force microscope. The main advantages of 3-D laser profilometry include the ease of implementation of the technique and its nondestructive nature, which does not require sample preparation (8-10). Moreover, the technique is reproducible and presents a high degree of freedom in the vertical axes (up to 1000 μm). However, when the paper surface presents a given roughness, if the pen impressions alter the paper with a depth similar to the roughness of medium, the results are not always conclusive (8). It becomes difficult in this case to distinguish which characteristics can be imputed to the pen impressions or the quality of the paper surface. This important limitation is assessed by testing different types of paper of variable quality (of different grammage and finishing) and the writing pressure. The authors will therefore assess the limits of 3-D laser profilometry technique and determine whether the method can overcome such constraints. Second, the authors will investigate the use of digital microscopy because it presents a number of advantages: it is efficient, user-friendly, and provides an objective evaluation and interpretation.

Development of a New Process for Determining Design Year Traffic Demands, TR-528, 2007

Researchers should continuously ask how to improve the models we rely on to make financial decisions in terms of the planning, design, construction, and maintenance of roadways. This project presents an alternative tool that will supplement local decision making but maintain a full appreciation of the complexity and sophistication of today’s regional model and local traffic impact study methodologies. This alternative method is tailored to the desires of local agencies, which requested a better, faster, and easier way to evaluate land uses and their impact on future traffic demands at the sub-area or project corridor levels. A particular emphasis was placed on scenario planning for currently undeveloped areas. The scenario planning tool was developed using actual land use and roadway information for the communities of Johnston and West Des Moines, Iowa. Both communities used the output from this process to make regular decisions regarding infrastructure investment, design, and land use planning. The City of Johnston case study included forecasting future traffic for the western portion of the city within a 2,600-acre area, which included 42 intersections. The City of West Des Moines case study included forecasting future traffic for the city’s western growth area covering over 30,000 acres and 331 intersections. Both studies included forecasting a.m. and p.m. peak-hour traffic volumes based upon a variety of different land use scenarios. The tool developed took goegraphic information system (GIS)-based parcel and roadway information, converted the data into a graphical spreadsheet tool, allowed the user to conduct trip generation, distribution, and assignment, and then to automatically convert the data into a Synchro roadway network which allows for capacity analysis and visualization. The operational delay outputs were converted back into a GIS thematic format for contrast and further scenario planning. This project has laid the groundwork for improving both planning and civil transportation decision making at the sub-regional, super-project level.

Roadway Lighting on Secondary Roads in Iowa, HR-251, 1984

There are approximately 800 installations of destination lighting at secondary road intersections in Iowa. Approximately 90% of these have only a single luminaire. The other installations have two luminaires. No warrants currently exist for justifying the use of this type of lighting. Previous research has examined the safety benefits from full lighting of rural intersections that generally serve substantially higher traffic volumes than secondary road intersections in Iowa. However, the safety benefit of destination lighting at intersections carrying relatively low volumes has not been the subject of previous research. The research reported here, sponsored by the Iowa Department of Transportation, was undertaken to identify locations where destination lighting could be expected to improve highway safety. If destination lighting were shown to reduce accident frequency, warrants for its use on secondary roads could be developed. An inventory of secondary road lighting installations in Iowa was assembled. From this inventory, two samples were constituted that would permit two separate comparisons of the accident experience with and without destination lighting. Before and after comparisons were made for the same locations if accident records were available for at least one full year both preceding and following the installation of destination lighting. Accident records for this purpose were available from a statewide computerized record system covering the period from 1977 through 1982. The accident experience at locations having destination lighting installed before 1978 was compared with a sample of comparable locations not having destination lighting. The sample of secondary road intersections used for the before and after comparison included 91 locations. The sample of continuously lighted locations included 102 intersections. Accident experience at these locations was compared with the experience at 102 intersections that were not lighted. The intersections included in these samples averaged only 0.31 accidents per year. The accident rate at secondary road intersections that had destination lighting did not differ significantly from the accident rate at intersections that were not lighted. This conclusion was derived from both comparisons, the before and after experience and the comparison of experience at intersections that were continuously lighted with that at unlighted locations. Furthermore, no significant differences were noted between lighted and unlighted locations in the proportion of accidents that occurred at night. The distribution of accidents by type also did not differ between unlighted intersections and those having destination lighting. It was not possible to formulate warrants for destination lighting since analyses directed toward identifying specific characteristics of an intersection that could be correlated with highway safety did not yield any useful relationships. However, it was noted that the average damages for night accidents that occurred at lighted intersections were lower than for accidents at unlighted intersections. Even in the absence of a more definitive demonstration of beneficial effects, destination lighting is perceived by officials in most of the counties having such installations as yielding desirable effects and is recognized as helpful to motorists in performing the guidance function in driving. Given this benefit and a relatively low cost (an average of $74 per year for one luminaire), and given that the subjective criteria that have been used in the past to justify the installation of destination lighting have led to a high degree of public acceptance and satisfaction, it is recommended that the same subjective criteria continue to be used in lieu of definitive warrants.