891 resultados para Tourist traffic


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Background: Few studies have used longitudinal ultrasound measurements to assess the effect of traffic-related air pollution on fetal growth.Objective: We examined the relationship between exposure to nitrogen dioxide (NO2) and aromatic hydrocarbons [benzene, toluene, ethylbenzene, m/p-xylene, and o-xylene (BTEX)] on fetal growth assessed by 1,692 ultrasound measurements among 562 pregnant women from the Sabadell cohort of the Spanish INMA (Environment and Childhood) study.Methods: We used temporally adjusted land-use regression models to estimate exposures to NO2 and BTEX. We fitted mixed-effects models to estimate longitudinal growth curves for femur length (FL), head circumference (HC), abdominal circumference (AC), biparietal diameter (BPD), and estimated fetal weight (EFW). Unconditional and conditional SD scores were calculated at 12, 20, and 32 weeks of gestation. Sensitivity analyses were performed considering time–activity patterns during pregnancy.Results: Exposure to BTEX from early pregnancy was negatively associated with growth in BPD during weeks 20–32. None of the other fetal growth parameters were associated with exposure to air pollution during pregnancy. When considering only women who spent 2 hr/day in nonresidential outdoor locations, effect estimates were stronger and statistically significant for the association between NO2 and growth in HC during weeks 12–20 and growth in AC, BPD, and EFW during weeks 20–32.Conclusions: Our results lend some support to an effect of exposure to traffic-related air pollutants from early pregnancy on fetal growth during mid-pregnancy.

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In recent years, the large deployment of mobile devices has led to a massiveincrease in the volume of records of where people have been and when they were there.The analysis of these spatio-temporal data can supply high-level human behaviorinformation valuable to urban planners, local authorities, and designer of location-basedservices. In this paper, we describe our approach to collect and analyze the history ofphysical presence of tourists from the digital footprints they publicly disclose on the web.Our work takes place in the Province of Florence in Italy, where the insights on thevisitors’ flows and on the nationalities of the tourists who do not sleep in town has beenlimited to information from survey-based hotel and museums frequentation. In fact, mostlocal authorities in the world must face this dearth of data on tourist dynamics. In thiscase study, we used a corpus of geographically referenced photos taken in the provinceby 4280 photographers over a period of 2 years. Based on the disclosure of the locationof the photos, we design geovisualizations to reveal the tourist concentration and spatiotemporalflows. Our initial results provide insights on the density of tourists, the points ofinterests they visit as well as the most common trajectories they follow.

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Standards for the construction of full-depth patching in portland cement concrete pavement usually require replacement of all deteriorated based materials with crushed stone, up to the bottom of the existing pavement layer. In an effort to reduce the time of patch construction and costs, the Iowa Department of Transportation and the Department of Civil, Construction and Environmental Engineering at Iowa State University studied the use of extra concrete depth as an option for base construction. This report compares the impact of additional concrete patching material depth on rate of strength gain, potential for early opening to traffic, patching costs, and long-term patch performance. This report also compares those characteristics in terms of early setting and standard concrete mixes. The results have the potential to change the method of Portland cement concrete pavement patch construction in Iowa.

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It is commonly regarded that the overuse of traffic control devices desensitizes drivers and leads to disrespect, especially for low-volume secondary roads with limited enforcement. The maintenance of traffic signs is also a tort liability concern, exacerbated by unnecessary signs. The Federal Highway Administration’s (FHWA) Manual on Uniform Traffic Control Devices (MUTCD) and the Institute of Transportation Engineer’s (ITE) Traffic Control Devices Handbook provide guidance for the implementation of STOP signs based on expected compliance with right-of-way rules, provision of through traffic flow, context (proximity to other controlled intersections), speed, sight distance, and crash history. The approach(es) to stop is left to engineering judgment and is usually dependent on traffic volume or functional class/continuity of system. Although presently being considered by the National Committee on Traffic Control Devices, traffic volume itself is not given as a criterion for implementation in the MUTCD. STOP signs have been installed at many locations for various reasons which no longer (or perhaps never) met engineering needs. If in fact the presence of STOP signs does not increase safety, removal should be considered. To date, however, no guidance exists for the removal of STOP signs at two-way stop-controlled intersections. The scope of this research is ultra-low-volume (< 150 daily entering vehicles) unpaved intersections in rural agricultural areas of Iowa, where each of the 99 counties may have as many as 300 or more STOP sign pairs. Overall safety performance is examined as a function of a county excessive use factor, developed specifically for this study and based on various volume ranges and terrain as a proxy for sight distance. Four conclusions are supported: (1) there is no statistical difference in the safety performance of ultra-low-volume stop-controlled and uncontrolled intersections for all drivers or for younger and older drivers (although interestingly, older drivers are underrepresented at both types of intersections); (2) compliance with stop control (as indicated by crash performance) does not appear to be affected by the use or excessive use of STOP signs, even when adjusted for volume and a sight distance proxy; (3) crash performance does not appear to be improved by the liberal use of stop control; (4) safety performance of uncontrolled intersections appears to decline relative to stop-controlled intersections above about 150 daily entering vehicles. Subject to adequate sight distance, traffic professionals may wish to consider removal of control below this threshold. The report concludes with a section on methods and legal considerations for safe removal of stop control.

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The Office of Transportation Data, in cooperation with the Federal Highway Administration, prepares this biennial traffic report. This report is used by federal, state, and local governmental agencies in determining highway needs, construction priorities, route location and environmental impact studies, and the application of appropriate design standards. The general public uses this information in determining the amount of traffic that passes a given area as they make their development plans and propose land use changes. The above reflects only a few of the many technical uses for this data.

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OBJECTIVE To describe the scientific knowledge produced about trauma in the elderly caused by traffic accidents in healthcare area studies. METHODS Integrative review of studies from 2003 to 2013 searched in LILACS, SciELO, PubMed and CINHAL databases. We used combination of the descriptors injuries, wounds and accidents, in English, Portuguese and Spanish languages. RESULTS 32 studies were selected. In the thematic analysis, three categories emerged: epidemiological data from traffic accidents involving elderly; traffic accidents with elderly pedestrians; and trauma care in the elderly. We observed increased incidence of trauma in most countries and pedestrians represented a large part of the victims. Among these, the elderly are the most vulnerable group. CONCLUSION Studies showed that trauma care in the elderly need protocols and professionals with training in gerontology specialized in trauma care services.

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We address the problem of scheduling a multiclass $M/M/m$ queue with Bernoulli feedback on $m$ parallel servers to minimize time-average linear holding costs. We analyze the performance of a heuristic priority-index rule, which extends Klimov's optimal solution to the single-server case: servers select preemptively customers with larger Klimov indices. We present closed-form suboptimality bounds (approximate optimality) for Klimov's rule, which imply that its suboptimality gap is uniformly bounded above with respect to (i) external arrival rates, as long as they stay within system capacity;and (ii) the number of servers. It follows that its relativesuboptimality gap vanishes in a heavy-traffic limit, as external arrival rates approach system capacity (heavy-traffic optimality). We obtain simpler expressions for the special no-feedback case, where the heuristic reduces to the classical $c \mu$ rule. Our analysis is based on comparing the expected cost of Klimov's ruleto the value of a strong linear programming (LP) relaxation of the system's region of achievable performance of mean queue lengths. In order to obtain this relaxation, we derive and exploit a new set ofwork decomposition laws for the parallel-server system. We further report on the results of a computational study on the quality of the $c \mu$ rule for parallel scheduling.

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Quarterly publication of the Governor's Traffic Safety Bureau, Iowa Department of Public Safety containing traffic safety and related information and news articles

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Quarterly publication of the Governor's Traffic Safety Bureau, Iowa Department of Public Safety containing traffic safety and related information and news articles

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We argue the importance both of developing simple sufficientconditions for the stability of general multiclass queueing networks and also of assessing such conditions under a range of assumptions on the weight of the traffic flowing between service stations. To achieve the former, we review a peak-rate stability condition and extend its range of application and for the latter, we introduce a generalisation of the Lu-Kumar network on which the stability condition may be tested for a range of traffic configurations. The peak-rate condition is close to exact when the between-station traffic is light, but degrades as this traffic increases.

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this report describes traffic law enforcement data collected by the Iowa State Patrol (ISP) related to traffic stops made by Troopers for October 1, 2000 through March 30, 2002. The data contained in this report summarizes the activities of approximately 435 troopers who are assigned to 15 posts throughout the State of Iowa The purpose of this voluntary data collection process was to provide the ISP with the ability to review traffic law enforcement variables in relation to traffic stops. The methodology for this research project was developed and implemented by ISP. Following the data collection period, the Iowa Division of Criminal and Juvenile Justice Planning (CJJP) was asked to assist in the analysis and reporting phase of this ambitious project.

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Mammalian sex chromosomes have undergone profound changes since evolving from ancestral autosomes. By examining retroposed genes in the human and mouse genomes, we demonstrate that, during evolution, the mammalian X chromosome has generated and recruited a disproportionately high number of functional retroposed genes, whereas the autosomes experienced lower gene turnover. Most autosomal copies originating from X-linked genes exhibited testis-biased expression. Such export is incompatible with mutational bias and is likely driven by natural selection to attain male germline function. However, the excess recruitment is consistent with a combination of both natural selection and mutational bias.

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This a survey that determines the total number and type of vehicles entering and leaving Indianola to obtain origin and destination data from representataive samples of those vehicles.