A Simulator Study of Driver Response to Changeable Message Signs of Differing Length and Format

Highway congestion nationwide continues to increase, and three Florida urban areas rank among the top ten. Congestion costs the State $3.5 billion annually in fuel and lost time, and is worsening because of: a) increasing population, b) projected travel increases, and c) recent legislation limiting additional highway capacity. Florida has been studying and implementing ITS technologies to address its congestion problems, with a focus on its special populations such as the elderly and multi-cultural groups for which English is not the primary language. One of these technologies most widely deployed is the changeable message sign (CMS). Fifty-two CMS are operational in Florida, with 39 more scheduled for deployment soon. Long-range plans will extend this technology Statewide. Although CMS have the potential to facilitate travel, certain issues must be considered to ensure that they do not exacerbate the congestion problem. Research has resulted in the development of guidelines which address message visibility, legibility and understandability. While these guidelines are helpful in informing the use of CMS, sign operation varies across jurisdictions, often without the basis of empirical support. Because successful CMS operation depends, in part, on driver information processing speed and linguistic ability, there is a need to evaluate CMS with Florida’s special populations. This study reports on an effort to determine the importance of specific CMS operational characteristics for drivers in general and elderly drivers in particular. One key CMS operational issue is the number of phases required to present a complete message. In one Florida jurisdiction about half of all CMS messages require one phase, and half require two. In another jurisdiction, fully 95 percent of CMS messages occupy two phases. There are also known cases of CMS using three-phase messages. “On-time” for two-phase messages varies from 2.5 to 5 seconds per phase across the State. Of course, the appropriateness of this on-time depends not only on the characteristics of the CMS itself (letter size, font, brightness, contrast, etc.), but on road, traffic and weather conditions, and, of course, on driver characteristics such as visual acuity, information processing speed, reading ability, and comprehension of English. This study, funded by the National Institute on Aging (NIA), investigated issues related to the number of CMS phases and their on-time. We used a low-cost, interactive driving simulator supplemented with a video monitor above the main display. While simulator screens presented interactive road and traffic conditions the supplemental monitor displayed the CMS. Young and old drivers drove the simulator under different workload conditions and responded to road closure/detour information on the CMS. All CMS displays were developed in accordance with accepted guidelines and were reviewed for content by independent experts. Results showed consistent and significant age effects across all tested conditions. In addition, we found significantly poorer response for all drivers under the two-phase CMS, despite the fact that our message “on-time” was nearly 2 seconds longer than that used in two major Florida jurisdictions. These findings have implications for CMS design and operation in Florida and in other jurisdictions with similar populations

Demonstrating Antenna Miniaturisation for Radiolocation Applications using Double Elliptical Patches

Double Elliptical Micro-strip Patch Antenna (DEMPA) is developed out of Double Elliptical Patch (DEP) which is a recently proposed shape of patch. The use of DEP results in higher flexibility in design of patch antenna and thus promotes antenna miniaturisation. The present work is an attempt to demonstrate the miniaturisation of radiolocation antenna through the concept of Design Flexibility (DF). In this paper, optimised neural network model for synthesis of DEMPA has been developed for radiolocation applications for which the earmarked frequency band is 8.50 GHz – 10.50 GHz. With the help of synthesis model, for an arbitrary operational frequency of 9.85 GHz, radiolocation antennas with effective patch area ranging from 142 mm2 to 66 mm2 were designed by using DEPs. In this case, the percentage reduction in effective patch area was found to be 53.52%. It shows that double elliptical patches can be employed to develop miniaturised radiolocation antennas. One prototype antenna was fabricated and tested to demonstrate the efficacy of the methodology adopted. The fabricated antenna had resonance at 10.15 GHz with a reflection coefficient of -20.73dB and bandwidth of 3.106 GHz (from 7.458 GHz to 10.564 GHz). Its Fractional Bandwidth was 34.469%. Positive and reasonably good gain was maintained over the entire working band. At resonance, the peak gain was 4.22 dB.The measured characteristics of antenna were in close agreement with the simulated results. The methodology presented in this paper can also be applied to frequency bands for other wireless applications

Peer-to-Peer, Permutable Models for DNS

Many leading analysts would agree that, had it not been for 128 bit architectures, the improvement of A* search might never have occurred. Given the current status of unstable configurations, systems engineers urgently desire the study of thin clients, demonstrates the significant importance of cryptoanalysis. In this work, we present an analysis of hierarchical databases (OmentalTrub), showing that the famous knowledge-based algorithm for the evaluation of IPv6 by Wu et al. is NP-complete

Diagnóstico y propuesta para el desarrollo turístico del cantón chunchi, provincia del Chimborazo

Este trabajo empieza por describir los cambios que han suscitado en el turista con respecto a los gustos al momento de escoger un destino para vacacionar, en este ítem se observa también cuál es la inclinación y qué lo motiva a trasladarse a lugares donde la naturaleza y la comunidad son los principales factores de entretenimiento. Se presenta luego, el objetivo general de esta investigación y los pasos que se siguieron para alcanzarlo, el primero consistió en identificar y valorar los componentes del sistema turístico de Chunchi, con esto se pudo constatar la realidad en la que se encuentran los elementos estáticos y dinámicos del sistema turístico; luego se procedió a realizar un Diagnóstico al Sistema Turístico del cantón, en este punto se da la Valorización de los Recursos y Atractivos Turísticos de Chunchi más detallada, se analiza el “Sistema Turístico Chunchi”, mediante la elaboración de un FODA, aquí se pudo apreciar de que forma funcionan y se interrelacionan los elementos del sistema turístico y es de este punto que se identificaron los problemas que no permiten que sea óptimo su funcionamiento; después se procedió a la elaboración de la propuesta que tiene como fin solucionar los problemas del sistema y ayudar al desarrollo del Turismo en este cantón, además se elaboró estrategia de promoción turística, que ayudara a alcanzar nuestro objetivo

Comparative evaluation of postoperative pain and periapical healing after root canal treatment using three different base endodontic sealers ? A randomized control clinical trial

The aim of the present study was to evaluate and compare the postoperative pain and periapical healing after root canal treatment using three different base endodontic sealers. Primary root canal treatment was initiated in 63 patients diagnosed with nec

Whole-genome shotgun sequence assembly enables rapid gene characterization in the tropical fish barramundi, Lates calcarifer

[Extract] Source description: Barramundi, Lates calcarifer, is a commercially important fish farmed throughout Australia and South-East Asia. Despite an increasing availability of genetic resources for the species (e.g. microsatellite and SNP markers, linkage and BAC-based maps and transcriptomic assemblies), the complete characterization of genes is still reliant on laborious molecular methods (e.g. genome walking/RACE PCR cloning/Sanger sequencing)

Observations on an Isolated Population of Sagitta hispida Conant (Chaetognatha) in a Tropical Lagoon System of Northeast Yucatan (Mexico)

Monthly zooplankton collections were carried out from January to December 1991 at two sampling sites, Cuenca Norte and Bojórquez lagoon, in the Nichupté lagoon system, a partially enclosed network of interconnected waterways located in the northeastern region of the Yucatan Peninsula (Mexico) adjacent to the Caribbean Sea. Only one species of Chaetognatha, Sagitta hispida Conant, was present and was more abundant at Cuenca Norte (total density 450.6 organisms/m3) than at Bojórquez (138.6 organisms/m3). The latter site is smaller, more physically isolated, and more environmentally stressed than the former. From monthly gonadal and length-frequency analyses of 1390 specimens, it was found that (1) total length significantly differed among four successive maturity stages, (2) juvenile and immature specimens occurred in greater numbers at Bojórquez. while more mature specimens comprised a greater percentage of individuals found at Cuenca Norte, and (3) individuals collected at Bojórquez, where slightly higher temperatures were recorded, were significantly smaller than those from Cuenca Norte. The latter two findings indicate that Sagitta hispida spawns at a higher frequency at Bojórquez, possibly due to the cumulative effect of higher temperature

Observations on an Isolated Population of Sagitta hispida Conant (Chaetognatha) in a Tropical Lagoon System of Northeast Yucatan (Mexico)

Monthly zooplankton collections were carried out from January to December 1991 at two sampling sites, Cuenca Norte and Bojórquez lagoon, in the Nichupté lagoon system, a partially enclosed network of interconnected waterways located in the northeastern region of the Yucatan Peninsula (Mexico) adjacent to the Caribbean Sea. Only one species of Chaetognatha, Sagitta hispida Conant, was present and was more abundant at Cuenca Norte (total density 450.6 organisms/m3) than at Bojórquez (138.6 organisms/m3). The latter site is smaller, more physically isolated, and more environmentally stressed than the former. From monthly gonadal and length-frequency analyses of 1390 specimens, it was found that (1) total length significantly differed among four successive maturity stages, (2) juvenile and immature specimens occurred in greater numbers at Bojórquez. while more mature specimens comprised a greater percentage of individuals found at Cuenca Norte, and (3) individuals collected at Bojórquez, where slightly higher temperatures were recorded, were significantly smaller than those from Cuenca Norte. The latter two findings indicate that Sagitta hispida spawns at a higher frequency at Bojórquez, possibly due to the cumulative effect of higher temperature

Geographic Proximity Not a Prerequisite for Invasion: Hawaii Not the Source of California Invasion by Light Brown Apple Moth (Epiphyas postvittana)

BACKGROUND: The light brown apple moth (LBAM), Epiphyas postvittana (Walker), is native to Australia but invaded England, New Zealand, and Hawaii more than 100 years ago. In temperate climates, LBAM can be a major agricultural pest. In 2006 LBAM was discovered in California, instigating eradication efforts and quarantine against Hawaiian agriculture, the assumption being that Hawaii was the source of the California infestation. Genetic relationships among populations in Hawaii, California, and New Zealand are crucial to understanding LBAM invasion dynamics across the Pacific. METHODOLOGY/PRINCIPAL FINDINGS: We sequenced mitochondrial DNA (mtDNA) from 1293 LBAM individuals from California (695), Hawaii (448), New Zealand (147), and Australia (3) to examine haplotype diversity and structure among introduced populations, and evaluate the null hypothesis that invasive populations are from a single panmictic source. However, invasive populations in California and New Zealand harbor deep genetic diversity, whereas Hawaii shows low level, shallow diversity. CONCLUSIONS/SIGNIFICANCE: LBAM recently has established itself in California, but was in Hawaii and New Zealand for hundreds of generations, yet California and New Zealand show similar levels of genetic diversity relative to Hawaii. Thus, there is no clear relationship between duration of invasion and genetic structure. Demographic statistics suggest rapid expansion occurring in California and past expansions in New Zealand; multiple introductions of diverse, genetically fragmented lineages could contribute to these patterns. Hawaii and California share no haplotypes, therefore, Hawaii is not the source of the California introduction. Paradoxically, Hawaii and California share multiple haplotypes with New Zealand. New Zealand may be the source for the California and Hawaii infestations, but the introductions were independent, and Hawaii was invaded only once. This has significant implications for quarantine, and suggests that probability of invasion is not directly related to geographic distance. Surprisingly, Hawaiian LBAM populations have much lower genetic diversity than California, despite being older