Highway Intersections Research Articles

Platinum emissions and levels in motorway dust samples: influence of traffic characteristics

An increase in the environmental levels of platinum can in part be attributed to the introduction of motor vehicle catalytic converters. Reported platinum levels in roadside dust samples range from 0.6 ng/g to 62.8±10.5 μg/g (dry weight, d.w.), with the highest levels in samples taken from inside road tunnels. Carriageway dust samples were collected from nine junctions (at sites of rush hour ‘stop–start’ activity or slip road on/off sections) of the London Orbital (M25) motorway and analysed for total Pt by inductively coupled plasma mass spectrometry (ICP-MS). These motorway junctions have mean daily traffic densities of 85,000 to 145,000 vehicles. Dust samples were fractionated (<75, 75–125 and 125–250 μm), microwave acid digested ( aqua rega/HF) and analysed using 195Pt + with polyatomic ion correction of 179Hf 16O +. Quality control validation was performed with replicate analysis of two certified reference materials, namely, NIST 2556 (Used Autocatalyst-Pellet) and 2557 (Used Autocatalyst-Monolith). Total platinum levels (sum total of all particle fractions) ranged from 101.6 to 764.2 ng/g (dry weight) in dust samples from all sampling sites. The highest Pt levels occur in the <75 and 75–125 μm particle fractions, with the fractionated samples ranging from 4.6 to 356.2 ng/g Pt (dry weight). Statistical analysis (Student t-test) confirmed that the significantly higher Pt levels (at the 95% confidence interval) occurred in dust samples taken from carriageway sites that had the vehicle slowing/stop–start driving conditions rather than for the accelerating speed zones. Correlation analysis showed that dust Pt levels, irrespective of fraction particle size, did not directly relate to traffic density, which is contrary to other published studies. The highest Pt levels occurred at the M25/A3 (Portsmouth/Guildford to London highway) intersection suggesting that traffic flow conditions, such as erratic stop–start flows, have a greater influence on Pt particle release and accumulation in the adjacent motorway environment than traffic density.

Characterization of nitrate particulate dry deposition by vacuum-deposited thin film reaction method

Abstract Air samples were collected at a highway intersection, coastal location and suburban area in Taichung, Taiwan for the characterization of nitrate containing particulates (NCPs) in dry deposition from October 2002 to February 2003. Sampling was accomplished with a surrogate surface technique in non-raining days. Collecting tapes were precoated with nitron (C20H16N4) in a vacuum evaporator controlled below 10−6 mm Hg. Immediately after collection, samples were placed in a desiccator with a relative humidity of 85% for 2 h to form distinctive products of NCPs. These products were then examined with a scanning electron microscopy. It was found that the average number frequencies of NCPs in total particulate were 41.9%, 35.7%, and 36.8% at the highway intersection, coastal and suburban areas, respectively. Most collected particulates were non-nitrate containing at these sampling sites. The average volume shape factor value of NCPs at the highway intersection was higher than those at the other sampling sites, suggesting that NCPs at the highway intersections were more irregular in shape. Average NCP dry deposition fluxes were 3.9, 2.2 and 2.1 μg m–2 s–1 and non-nitrate containing particulate dry deposition fluxes were 5.4, 3.9 and 3.2 μg m–2 s–1 at the highway intersection, coastal and suburban areas. NCPs

Development of Accident Prediction Models for Rural Highway Intersections

A study was done to develop macrolevel crash prediction models that can be used to understand and identify effective countermeasures for improving signalized highway intersections and multilane stop-controlled highway intersections in rural areas. Poisson and negative binomial regression models were fit to intersection crash data from Georgia, California, and Michigan. To assess the suitability of the models, several goodness-of-fit measures were computed. The statistical models were then used to shed light on the relationships between crash occurrence and traffic and geometric features of the rural signalized intersections. The results revealed that traffic flow variables significantly affected the overall safety performance of the intersections regardless of intersection type and that the geometric features of intersections varied across intersection type and also influenced crash type.

Dry deposition of sulfate-containing particulate at the highway intersection, coastal and suburban areas

Sulfate-containing aerosol (SCA) dry deposition at the highway intersection, coastal location, and suburban area in Taiwan were analyzed and compared. Sampling was accomplished with a surrogate surface technique. Samples particles were coated with barium chloride (BaCl 2) in a vacuum evaporator and then exposed to a relative humidity of 85% for 2 h to form distinctive products of SCAs. Treated samples were examined by a scanning electron microscopy. SCA dry deposition fluxes were 10.2, 4.1, 3.4 μg m −2 s −1 and nonsulfate-containing aerosol (NSCA) dry deposition fluxes were 23.3, 8.2, 13.5 μg m −2 s −1 at the highway intersection, coastal, and suburban areas. At the highway intersection, both SCA and NSCA dry deposition fluxes were much higher than those at the other two sites. The dry deposition of particles was also analyzed with a traditional technique. The number median diameters (NMDs) of SCA were 0.41, 0.82, and 1.2 μm at the highway intersection, coastal, and suburban sites, respectively. The highway intersection site had a small NMD, which showed that most sulfate-containing deposited aerosols existed in fine diameter range. The mass median diameters (MMDs) of SCA were 8.8, 19.5, and 14.9 μm at the highway intersection, coastal, and suburban sites, which were much higher than NMDs. Average numbers of SCAs in total particulate were 33%, 33%, and 22% at the highway intersection, coastal and suburban areas Most deposited particulates were nonsulfate-containing at the three sampling sites. SCAs less than 10 μm contributed 29%, 8%, and 7% to the total dry deposition at the highway intersection, coastal, and suburban areas, respectively. The contribution of fine particulate was significantly higher at the highway intersection site.

DNA-adduct formation in lungs, nasal mucosa, and livers of rats exposed to urban roadside air in Kawasaki City, Japan

The potency of ambient air for DNA-adduct formation was estimated using Wistar rats. The animals were maintained in a small-animal facility located beside a main highway intersection in Kawasaki City, Japan, for up to 60 weeks and were exposed to roadside air contaminated mainly with automobile emission (exposure group, EG) or to clean air (control group, CG). Compared to CG, the relative adduct levels (RAL) were increased significantly in EG lungs (17.1-fold ( P<0.05)), nasal mucosa, and livers after exposure for 4 weeks. However, there were no significant differences in RAL between EG and CG after exposure for 12 weeks, but they were elevated again in EG after exposure for 48 or 60 weeks. These results suggest that roadside air in this region can cause the generation of DNA adducts. This activity of ambient roadside air can be estimated using experimental animals, indicating that biological monitoring of DNA-adduct formation may be a powerful tool to assess the effect of ambient air on human health.

Coumarins and a kaurane from Gochnatia polymorpha ssp. polymorpha from Paraguay

Aerial parts of Gochnatia polymorpha (Less.) Cabrera ssp. polymorpha were collected on December 14, 1997 in Paraguay, Departmento Concepcion, at Yby-Jau at the intersection of highways 3 and 5. A voucher specimen is on deposit in the herbarium at the Instituto Miguel Lillo, Tucuman (leg. A. Schinini and M. Demathesis No. 33692, LIL 552576). Aerial parts of Gochnatia haumaniana Cabr. were collected at the flowering stage on December 14, 1997 in the Departamento Amambay, Paraguay. A voucher specimen (leg. A. Schinini and M. Dematheis No. 33437) is on deposit in the herbarium of the Instituto de Miguel Lillo (LIL 355735).

Blood lead levels and risk factors for lead poisoning among children in Jakarta, Indonesia

The phase-out of leaded gasoline began in Jakarta, Indonesia on July 1, 2001. We evaluated mean blood lead levels (BLLs) and the prevalence of elevated BLLs of Jakarta school children and assessed risk factors for lead exposure in these children before the beginning of the phase-out activities. The study involved a population-based, cross-sectional blood lead survey that included capillary blood lead sampling and a brief questionnaire on risk factors for lead poisoning. A cluster survey design was used. Forty clusters, defined as primary schools in Jakarta, and 15 2nd- and 3rd-grade children in each cluster were randomly selected for participation in the study. The average age of children in this study was 8.6 years (range 6–12) and the geometric mean BLL of the children was 8.6 μg/dl (median: 8.6 μg/dl; range: 2.6–24.1 μg/dl) ( n=397). Thirty-five percent of children had BLLs ≥10 μg/dl and 2.4% had BLLs ≥20 μg/dl. Approximately one-fourth of children had BLLs 10–14.9 μg/dl. In multivariate models, level of education of the child's primary caregiver, water collection method, home varnishing and occupational recycling of metals, other than lead, by a family member were predictors of log BLLs after adjustment for age and sex. BLLs of children who lived near a highway or major intersection were significantly higher than those of children who lived near a street with little or no traffic when level of education was not included in the model. Water collection method was a significant predictor of BLLs ≥10 μg/dl after adjustment for age and sex. BLLs in children in this study were moderately high and consistent with BLLs of children in other countries where leaded gasoline is used. With the phase-out of leaded gasoline, BLLs of children in Jakarta are expected to rapidly decline as they have in other countries that have phased lead out of gasoline.

City center revitalization in Portugal

Retail activity in Portugal is undergoing tremendous changes. New forms of commercial development, such as shopping centers and hypermarkets, have been built in locations far from the traditional shopping districts, and normally near a major road or highway intersection. This out-of-town commercial development has impacts on traditional forms of retail in established city centers. This article analyzes ways in which retail planning and city center commercial revitalization can be used to make Portuguese city centers more livable for city dwellers. Its main objective is to categorize, evaluate and compare the actions proposed by two commercial urbanism projects in Portugal. This study uses the cities of Coimbra and Aveiro to discuss the hypothesis that the measures proposed under the PROCOM program will help to revitalize Portuguese city centers. The key finding is that commercial revitalization is crucial for the livability of Portuguese city centers.

Queueing delay models for two-lane highway work zones

The paper describes the adaptation and application of queueing models to estimate average delay at two-lane highways operating with a lane closure. In their original form, the queueing models predicted impacts at highway intersections controlled by vehicle-actuated traffic signals. Validation efforts using simulation indicate that the adapted delay models adequately predict traffic performance at two-lane highway lane closures.

Highway Intersection Sight Distance Guidelines &amp; Measurements

Many Highway Accidents Occur At Intersections That Are Not Controlled By Traffic Signals. Intersecting Roadways, Driveways, And Entrances To Shopping Malls Are Only A Few Examples Of Where Crashes Occur. In Some Cases Tort Lawsuits Are Brought Against The Highway Agency Claiming That There Was A Lack Of Sight Distance At The Intersection. Unfortunately, Many Engineers And Accident Reconstruction Professionals Do Not Understand Intersection Sight Distance Requirements And Guidelines. This Confusion Often Leads To Needless Litigation. This Paper Will Review The Highway Design Guidelines (Aashto) Which Are Used To Evaluate Intersection Sight Distance For Both Turning And Straight Through Traffic Movements. It Will Explain The Rationale For The Criteria And How It Should Be Applied For Accident Analysis. The Drivers Responsibility, Under The Vehicle Code, At An Intersection Is Reviewed. A Case Study Will Be Used As An Example To Explain The Procedures For Field Measurements At An Intersection.

UPA, uPAR, PAI-I: Key intersection of proteolytic, adhesive and chemotacfic highways?

Through multiple interactions, the unpkinase plasminogen in tivator (uPA) system forms n self-regulated, surface-located, functionally important chemokine. This article examines new data in the field.

A Study of Traffic Signal Violations at Highway Intersections

A research study of drivers non-compliance with traffic signals, covering 19 interurban signalised highway intersections in Northern Greece is presented in this paper. The objective of the study is to identify the interrelations between traffic signal violations and roadway, traffic and operational features of the intersection. The results of the study indicate that traffic signal violation at interurban intersections is a major problem, which requires emergency attention. Four out of ten (4/10) drivers violate the red signal. The violation rate is higher for left and right turns, for motorcycles and during low traffic volumes.

Application of millimeter‐wave radar traffic observation system

AbstractTraffic monitoring systems employ, as sensors, infrared image systems, visible light image systems, and so on. But observation with such monitoring systems are limited to highway interchange areas and intersections of large roads. Also, such systems often fail to detect vehicles hidden by obstacles such as roadside trees because the sensors are easily affected by weather conditions such as rain and dense fog.This paper discusses sensors using 94‐GHz millimeter‐wave radar in traffic observation systems. These sensors make it possible to observe hidden cars and to reduce the influence of weather and are unaffected by night and day conditions.In addition, it is possible to improve the observation ability by using both the current system and the 94‐GHz millimeter‐wave radar for unattended observation of traffic within the range of 1 km.

Observations on the Fall Migration of Eared Grebes, Based on Evidence from a Mass Downing in Utah

After the breeding season in North America, most Eared Grebes (Podiceps nigricollis) migrate to highly saline lakes in the Great Basin to molt and stage for several months. During this period they molt, undergo a cycle of breast muscle atrophy and hypertropy, and accumulate huge fat deposits before flying to wintering areas (Jehl 1988, unpubl. manuscript; Gaunt et al. 1990). On 10 December 1991 thousands of grebes departed Great Salt Lake en route to the Salton Sea, California, or Gulf of California, Mexico. Their route was southwesterly, and for the first 500 km-roughly between Salt Lake City and the Arizona border-paralleled Interstate Highway 15 and the Wasatch Mountains, which are slightly to the east. Several hours into the flight, over southern and central Utah, large numbers were forced down by a snowstorm along a 180 km stretch between Holden and Cedar City; a few were also reported in the Provo/Springfield area (Fig. 1). The birds did not fall uniformly, but apparently were attracted to lights from towns and highway intersections. Many died when they crashed to earth; others were hit by cars on the highway, which they evidently mistook for open water. Thousands more were captured alive and released on whatever local water bodies remained open. Most of our current understanding about the biology of Eared Grebes in fall migration is based on studies of birds staging at Mono Lake, California (Jehl 1988). The data from this downing provided an opportunity to test and extend some earlier findings or inferences about the differential migration of age classes, duration of the flight to wintering areas, physical condition of departing and arriving migrants, the size of pectoral muscles needed for flight, and the risks of mortality along the migratory routes (Jehl 1988, Gaunt et al. 1990).

Individual Differences and Driver Response to Highway Intersections

Along the Nation's roadways one of the most dangerous environments is the intersection. Accident investigations suggest several individual driver characteristics that may be associated with increased risk at intersections. To analyze the relationships of a number of driver characteristics to driver behavior in a controlled setting a laboratory simulation of the roadway intersection was created. Seventy-two research participants, ranging in age from 18 to 74, were measured on a battery of performance tests, administered questionnaires related to health and driving history, and exposed to a video display of approaching intersections as driver responses were measured. Each participant viewed 14 intersections containing a variety of traffic control devices. During the driving simulation portion of the research workload was assessed using six variables chosen to reflect three response modes-performance, subjective, and physiological. A MANOVA conducted to analyze the 3 (age level) by 2 (gender) factorial design indicated a main effect for both age and gender, based on three of the dependent variables-pedal response errors, speed of response, and heart rate reactivity. The responses to the intersection simulation indicated greater workloads for older drivers and female drivers. In a second phase of the data analysis stepwise multiple regressions were used to determine which independent variables, from among a set of driver characteristics, functioned as the best predictors of these performance decrements. As expected from the earlier MANOVA and univariate tests, age accounted for more variance in driver response than any single information processing variable. However, information processing variables that were most predictive of performance decrements included: field dependency, visual acuity, and depth perception.

DESIGN AND CONSTRUCTION OF A MODEL PRESTRESSED CONCRETE BIFURCATED BOX GIRDER BRIDGE.

The design and construction of a 1:12 scale prestressed concrete spine beam model of an elevated highway intersection is described. The model represents a four-lane carriageway bifurcating into three-and two-lane spans, and is of typical single and double box girder construction, incorporating large side cantilevers. The bridge, highly curved in plan, is continuous over three central supports and torsionally restrained at three outer supports. The strain history during prestressing and the accuracy of the data are discussed. A total of over 1000 electical resistance strain gauges, linear displacement transducers and dial gauges were used to provide details of the state of strain, reactions and prestress force at all stages. (Author/TRRL)

THE MORPHOLOGY AND VITALITY OF BUSINESS DISTRICTS IN UPSTATE NEW YORK VILLAGES1

Field examination of 40 upstate New York villages reveals their commercial structure consists of six common elements: CBDs, railroad-oriented districts, early automobile expansion zones, mixed use areas, outlying commercial strips, and highway commercial intersections. The economic health of CBDs is quantified by a “downtown vitality index.”Variation in the observed vitality of downtowns may be attributed to site and situation factors, including downtown centrality with respect to the surrounding population, route layout, and regional location of the community. Downtowns are not being abandoned so much as changing their function.

Precise Gravity Survey Across Newport-Inglewood Structural Zone, Long Beach, California: ABSTRACT

A major strand of the Newport-Inglewood structural zone in Long Beach, California, has an estimated vertical uplift of 490 ft (150 m) along its west side as based on a precise gravity survey conducted in October 1979. This strand has a northwest strike and underlies the vicinity of the intersection of Seventh Street and Pacific Coast Highway. This fault strand, as delineated by gravity, is in agreement with well data from the northern extension of the Seal Beach oil field which the survey line crosses. However, the geometry of the structural zone, as modeled from the survey, is in conflict with that of R. F. Yerkes. This fault strand has an associated gravity anomaly of ¢2.25 mgal at the southern end of the survey. The anomaly begins at California State University, Long Beach, and continues southward, possibly through the southeast offshore extension of the Wilmington oil field. The anomaly is presumably based on vertical offset of Franciscan(?) basement schist against overlying Miocene Monterey Formation and San Onofre breccia. This offset causes an estimated density contrast of 0.2 g/cc across the fault at a depth, as projected from nearby well data, of about 9,200 ft (2,800 m). A graphical regional-residual separation indicated a regional gradient 4.5 mgal/km which compares with the regional value of 3.0 mgal/km by L. L. Nettleton. The instrument used was a LaCoste and Romberg G model gravity meter with an elevation accuracy of ±0.01 mgal. End_of_Article - Last_Page 1701------------

Centro de Conferencias, Hotel y Mezquita Riyadh - Arabia Saudita

The complex, designed and built for the Finance Ministry of the Kingdom of Saudi Arabia, is located on a 78,000 m 2 lot, close to the intersection of highways crossing the Arabian desert, which connect the location directly with the area of public buildings of the city and with the airport as well. The complex situates the Convention Hall, with 23,230 m 2 of constructed surface, in the southeast half of the lot; the Hotel, with 14,860 m 2 of constructed surface, Is on the other half. Each has independent accesses, as is the case of the Mosque which is located at one end of the lot. Individual dwellings three-storeys high, gardens, parking areas, service roads an auxiliary buildings have been constructed next to the Mosque.

Benthic Macroinvertebrates of Boomer Lake, Payne County, Oklahoma

A study of benthic macroinvertebrates in a 102 ha lake was con- ducted from March, 1966 through February, 1967. Of the thirty taxa collected, seven (Chaoborus punctipennis (Say), Caenis, Sialis, Hexagenia, Hyalella azteca (Saussure), Branchiura sowerbyi Beddard, and Tendipedidae) comprised 82.74 to 99.51% of the total organisms collected monthly. Seven taxa of oligochaetes were collected, the most abundant being B. sowerbyi. Abundance of C. punctipennis increased as depth of water increased. Depth dis- tribution of Tendipedidae was unclear since the family was treated as a single taxon. Other taxa, except Hexagenia which is treated in another presentation were not abundant enough in collections to elicit a distinct depth distribution. Variation and abundance of fauna may have been limited by silt depositions dur- ing run-off. The amount of silt was apparent by the abundance of Hexagenia. Studies of benthic macroinvertebrates in Oklahoma have generally been restricted to streams (Hornuff, 1957; Wilhm, 1964; Harrel, 1966;) or large impoundments (Sublette, 1957). In order to better establish the ecological requirements and the taxa present in Okla- homa, data from all impoundments offering different abiotic and biotic factors. should be collected and analyzed. The objective of this presentation is to list the benthic macroinverte- brates, and related ecological observations, collected during a study of Boomer Lake from March, 1966 through February, 1967. DESCRIPTION OF LAKE. Boomer Lake, completed in 1925, is lo- cated three km north of the intersection of state highways 51 and 177. The reservoir initially was used for a municipal water supply, but in 1951, the city discontinued use of the lake for this purpose. Presently, the water is used for irrigation of the park around the lake and as a source of coolant water for the Boomer Lake power station. Morpho- metric data are presented in Table 1.