WorldWideScience

Sample records for average daily traffic

  1. Estimation of annual average daily traffic with optimal adjustment factors

    OpenAIRE

    Alonso Oreña, Borja; Moura Berodia, José Luis; Ibeas Portilla, Ángel; Romero Junquera, Juan Pablo

    2014-01-01

    This study aimed to estimate the annual average daily traffic in inter-urban networks determining the best correlation (affinity) between the short period traffic counts and permanent traffic counters. A bi-level optimisation problem is proposed in which an agent in an upper level prefixes the affinities between short period traffic counts and permanent traffic counters stations and looks to minimise the annual average daily traffic calculation error while, in a lower level, an origin–destina...

  2. Caltrans Average Annual Daily Traffic Volumes (2004)

    Data.gov (United States)

    California Environmental Health Tracking Program — [ from http://www.ehib.org/cma/topic.jsp?topic_key=79 ] Traffic exhaust pollutants include compounds such as carbon monoxide, nitrogen oxides, particulates (fine...

  3. Phase diagram distortion from traffic parameter averaging.

    NARCIS (Netherlands)

    Stipdonk, H. Toorenburg, J. van & Postema, M.

    2010-01-01

    Motorway traffic congestion is a major bottleneck for economic growth. Therefore, research of traffic behaviour is carried out in many countries. Although well describing the undersaturated free flow phase as an almost straight line in a (k,q)-phase diagram, congested traffic observations and theori

  4. Traffic Analysis Zones, Traffic Counts; s44ttc02; This data set contains the annual 24 Hour Average Daily Traffic Count Locations on State maintained roads in Rhode Island for 2001., Published in 2003, 1:4800 (1in=400ft) scale, State of Rhode Island and Providence Plantations.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Traffic Analysis Zones dataset, published at 1:4800 (1in=400ft) scale, was produced all or in part from Hardcopy Maps information as of 2003. It is described as...

  5. Do Diurnal Aerosol Changes Affect Daily Average Radiative Forcing?

    Energy Technology Data Exchange (ETDEWEB)

    Kassianov, Evgueni I.; Barnard, James C.; Pekour, Mikhail S.; Berg, Larry K.; Michalsky, Joseph J.; Lantz, K.; Hodges, G. B.

    2013-06-17

    Strong diurnal variability of aerosol has been observed frequently for many urban/industrial regions. How this variability may alter the direct aerosol radiative forcing (DARF), however, is largely unknown. To quantify changes in the time-averaged DARF, we perform an assessment of 29 days of high temporal resolution ground-based data collected during the Two-Column Aerosol Project (TCAP) on Cape Cod, which is downwind of metropolitan areas. We demonstrate that strong diurnal changes of aerosol loading (about 20% on average) have a negligible impact on the 24-h average DARF, when daily averaged optical properties are used to find this quantity. However, when there is a sparse temporal sampling of aerosol properties, which may preclude the calculation of daily averaged optical properties, large errors (up to 100%) in the computed DARF may occur. We describe a simple way of reducing these errors, which suggests the minimal temporal sampling needed to accurately find the forcing.

  6. Yearly-averaged daily usefulness efficiency of heliostat surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Elsayed, M.M.; Habeebuallah, M.B.; Al-Rabghi, O.M. (King Abdulaziz Univ., Jeddah (Saudi Arabia))

    1992-08-01

    An analytical expression for estimating the instantaneous usefulness efficiency of a heliostat surface is obtained. A systematic procedure is then introduced to calculate the usefulness efficiency even when overlapping of blocking and shadowing on a heliostat surface exist. For possible estimation of the reflected energy from a given field, the local yearly-averaged daily usefulness efficiency is calculated. This efficiency is found to depend on site latitude angle, radial distance from the tower measured in tower heights, heliostat position azimuth angle and the radial spacing between heliostats. Charts for the local yearly-averaged daily usefulness efficiency are presented for {phi} = 0, 15, 30, and 45 N. These charts can be used in calculating the reflected radiation from a given cell. Utilization of these charts is demonstrated.

  7. [Estimation of average traffic emission factor based on synchronized incremental traffic flow and air pollutant concentration].

    Science.gov (United States)

    Li, Run-Kui; Zhao, Tong; Li, Zhi-Peng; Ding, Wen-Jun; Cui, Xiao-Yong; Xu, Qun; Song, Xian-Feng

    2014-04-01

    On-road vehicle emissions have become the main source of urban air pollution and attracted broad attentions. Vehicle emission factor is a basic parameter to reflect the status of vehicle emissions, but the measured emission factor is difficult to obtain, and the simulated emission factor is not localized in China. Based on the synchronized increments of traffic flow and concentration of air pollutants in the morning rush hour period, while meteorological condition and background air pollution concentration retain relatively stable, the relationship between the increase of traffic and the increase of air pollution concentration close to a road is established. Infinite line source Gaussian dispersion model was transformed for the inversion of average vehicle emission factors. A case study was conducted on a main road in Beijing. Traffic flow, meteorological data and carbon monoxide (CO) concentration were collected to estimate average vehicle emission factors of CO. The results were compared with simulated emission factors of COPERT4 model. Results showed that the average emission factors estimated by the proposed approach and COPERT4 in August were 2.0 g x km(-1) and 1.2 g x km(-1), respectively, and in December were 5.5 g x km(-1) and 5.2 g x km(-1), respectively. The emission factors from the proposed approach and COPERT4 showed close values and similar seasonal trends. The proposed method for average emission factor estimation eliminates the disturbance of background concentrations and potentially provides real-time access to vehicle fleet emission factors.

  8. Declining average daily census. Part 2: Possible solutions.

    Science.gov (United States)

    Weil, T P

    1986-01-01

    Several possible solutions are available to hospitals experiencing a declining average daily census, including: Closure of some U.S. hospitals; Joint ventures between physicians and hospitals; Development of integrated and coordinated medical-fiscal-management information systems; Improvements in the hospital's short-term marketing strategy; Reduction of the facility's internal operation expenses; Vertical more than horizontal diversification to develop a multilevel (acute through home care) regional health care system with an alternative health care payment system that is a joint venture with the medical staff(s); Acquisition or management by a not-for-profit or investor-owned multihospital system (emphasis on horizontal versus vertical integration). Many reasons exist for an institution to choose the solution of developing a regional multilevel health care system rather than being part of a large, geographically scattered, multihospital system. Geographic proximity, lenders' preferences, service integration, management recruitment, and local remedies to a declining census all favor the regional system. More answers lie in emphasizing the basics of health care regionalization and focusing on vertical integration, including a prepayment plan, rather than stressing large multihospital systems with institutions in several states or selling out to the investor-owned groups.

  9. Relationships between feeding behavior and average daily gain in cattle

    Directory of Open Access Journals (Sweden)

    Bruno Fagundes Cunha Lage

    2013-12-01

    Full Text Available Several studies have reported relationship between eating behavior and performance in feedlot cattle. The evaluation of behavior traits demands high degree of work and trained manpower, therefore, in recent years has been used an automated feed intake measurement system (GrowSafe System ®, that identify and record individual feeding patterns. The aim of this study was to evaluate the relationship between feeding behavior traits and average daily gain in Nellore calves undergoing feed efficiency test. Date from 85 Nelore males was recorded during the feed efficiency test performed in 2012, at Centro APTA Bovinos de Corte, Instituto de Zootecnia, São Paulo State. Were analyzed the behavioral traits: time at feeder (TF, head down duration (HD, representing the time when the animal is actually eating, frequency of visits (FV and feed rate (FR calculated as the amount of dry matter (DM consumed by time at feeder (g.min-1. The ADG was calculated by linear regression of individual weights on days in test. ADG classes were obtained considering the average ADG and standard deviation (SD being: high ADG (>mean + 1.0 SD, medium ADG (± 1.0 SD from the mean and low ADG (0.05 among ADG classes for FV, indicating that these traits are not related to each other. These results shows that the ADG is related to the agility in eat food and not to the time spent in the bunk or to the number of visits in a range of 24 hours.

  10. Daily and seasonal variation of traffic related aerosol pollution in Thessaloniki, Greece, during the financial crisis

    Science.gov (United States)

    Vouitsis, Ilias; Amanatidis, Stavros; Ntziachristos, Leonidas; Kelessis, Apostolos; Petrakakis, Maximos; Stamos, Iraklis; Mitsakis, Evangelos; Samaras, Zissis

    2015-12-01

    Airborne urban particulate and gaseous pollutants measurements were conducted at the kerbside of a busy road and at a nearby urban background site of Thessaloniki, Greece, during a winter and a summer period. The main objective was to observe how the financial crisis has affected the air quality in the city, compared to previous measurements. Compared to a study conducted in 2006, the current work suggests that although average concentrations at the traffic affected site remain higher that in the urban background station, the differences are much smaller than in the past. A number of observations suggest a scenario of decrease in traffic activity and increase in biomass burning for residential heating. On this basis, the results suggest that traffic may be less important as an air quality contributor in a financially hit city. On the contrary, domestic heating appears as a significant contributor and affects areas of the city that were earlier not being of environmental concern. Because of the impact of biomass burning in residential areas, exposure calculations are required to estimate whether traffic or biomass burning is the overall highest contributors to daily PM dosages that citizens of the city are exposed to.

  11. Simulation of mosquitoes population dynamic based on rainfall and average daily temperature

    Science.gov (United States)

    Widayani, H.; Seprianus, Nuraini, N.; Arum, J.

    2014-02-01

    This paper proposed rainfall and average daily temperature approximation functions using least square method with trigonometry polynomial. Error value from this method is better than Fast Fourier Transform method. This approximation is used to accommodate climatic factors into deterministic model of mosquitoes population by constructing a carrying capacity function which contains rainfall and average daily temperature functions. We develop a mathematical model for mosquitoes population dynamic which formulated by Yang et al (2010) with dynamic parameter of a daily rainfall as well as temperature on that model. Two fixed points, trivial and non-trivial, are obtained when constant entomological parameters assumed. Basic offspring number, Q0 as mosquitoes reproduction parameter is constructed. Non-trivial fixed point is stable if and only if Q0 > 1. Numerical simulation shown the dynamics of mosquitoes population significantly affected by rainfall and average daily temperature function.

  12. Exponential approximation for daily average solar heating or photolysis. [of stratospheric ozone layer

    Science.gov (United States)

    Cogley, A. C.; Borucki, W. J.

    1976-01-01

    When incorporating formulations of instantaneous solar heating or photolytic rates as functions of altitude and sun angle into long range forecasting models, it may be desirable to replace the time integrals by daily average rates that are simple functions of latitude and season. This replacement is accomplished by approximating the integral over the solar day by a pure exponential. This gives a daily average rate as a multiplication factor times the instantaneous rate evaluated at an appropriate sun angle. The accuracy of the exponential approximation is investigated by a sample calculation using an instantaneous ozone heating formulation available in the literature.

  13. Association between average daily gain, faecal dry matter content and concentration of Lawsonia intracellularis in faeces

    DEFF Research Database (Denmark)

    Pedersen, Ken Steen; Skrubel, Rikke; Stege, Helle;

    2012-01-01

    Background The objective of this study was to investigate the association between average daily gain and the number of Lawsonia intracellularis bacteria in faeces of growing pigs with different levels of diarrhoea. Methods A longitudinal field study (n?=?150 pigs) was performed in a Danish herd f...

  14. Deriving average delay of traffic flow around intersections from vehicle trajectory data

    Institute of Scientific and Technical Information of China (English)

    Minyue ZHAO; Xiang LI

    2013-01-01

    Advances of positioning and wireless communication technologies make it possible to collect a large number of trajectory data of moving vehicles in a fast and convenient fashion.The data can be applied to various fields such as traffic study.In this paper,we attempt to derive average delay of traffic flow around intersections and verify the results with changes of time.The intersection zone is delineated first.Positioning points geographically located within this zone are selected,and then outliers are removed.Turn trips are extracted from selected trajectory data.Each trip,physically consisting of time-series positioning points,is identified with entry road segment and turning direction,i.e.target road segment.Turn trips are grouped into different categories according to their time attributes.Then,delay of each trip during a turn is calculated with its recorded speed.Delays of all trips in the same period of time are plotted to observe the change pattern of traffic conditions.Compared to conventional approaches,the proposed method can be applied to those intersections without fixed data collection devices such as loop detectors since a large number of trajectory data can always provide a more complete spatio-temporal picture of a road network.With respect to data availability,taxi trajectory data and an intersection in Shanghai are employed to test the proposed methodology.Results demonstrate its applicability.

  15. On the Relationship between Duration of Vegetative Growth Stage of Wheat and the Average Daily Temperature

    Institute of Scientific and Technical Information of China (English)

    Hua; YU; Juanjuan; ZHANG; Yanhong; SUN; Xinming; MA

    2014-01-01

    Using the modern information technology,this paper analyzes the 20 years of experimental observation data of wheat ear differentiation research team led by Professor Cui Jinmei.It reveals that in the appropriate sowing period,there is a quartic polynomial regression relationship between the sowing period and spike primordium period,namely between duration of vegetative growth stage and the average daily temperature.It is of great significance to determining the suitable sowing period of wheat.

  16. Feedlot cattle with calm temperaments have higher average daily gains than cattle with excitable temperaments.

    Science.gov (United States)

    Voisinet, B D; Grandin, T; Tatum, J D; O'Connor, S F; Struthers, J J

    1997-04-01

    This study was conducted to assess the effect of temperament on the average daily gains of feedlot cattle. Cattle (292 steers and 144 heifers) were transported to Colorado feedlot facilities. Breeds studied included Braford (n = 177), Simmental x Red Angus (n = 92), Red Brangus (n = 70), Simbrah (n = 65), Angus (n = 18), and Tarentaise x Angus (n = 14). Cattle were temperament rated on a numerical scale (chute score) during routine weighing and processing. Data were separated into two groups based on breed, Brahman cross (> or = 25% Brahman) and nonBrahman breeding. Animals that had Brahman breeding had a higher mean temperament rating (3.45 +/- .09) or were more excitable than animals that had no Brahman influence (1.80 +/- .10); (P < .001). These data also show that heifers have a higher mean temperament rating than steers (P < .05). Temperament scores evaluated for each breed group also showed that increased temperament score resulted in decreased average daily gains (P < .05). These data show that cattle that were quieter and calmer during handling had greater average daily gains than cattle that became agitated during routine handling.

  17. An examination of population exposure to traffic related air pollution: Comparing spatially and temporally resolved estimates against long-term average exposures at the home location.

    Science.gov (United States)

    Shekarrizfard, Maryam; Faghih-Imani, Ahmadreza; Hatzopoulou, Marianne

    2016-05-01

    Air pollution in metropolitan areas is mainly caused by traffic emissions. This study presents the development of a model chain consisting of a transportation model, an emissions model, and atmospheric dispersion model, applied to dynamically evaluate individuals' exposure to air pollution by intersecting daily trajectories of individuals and hourly spatial variations of air pollution across the study domain. This dynamic approach is implemented in Montreal, Canada to highlight the advantages of the method for exposure analysis. The results for nitrogen dioxide (NO2), a marker of traffic related air pollution, reveal significant differences when relying on spatially and temporally resolved concentrations combined with individuals' daily trajectories compared to a long-term average NO2 concentration at the home location. We observe that NO2 exposures based on trips and activity locations visited throughout the day were often more elevated than daily NO2 concentrations at the home location. The percentage of all individuals with a lower 24-hour daily average at home compared to their 24-hour mobility exposure is 89.6%, of which 31% of individuals increase their exposure by more than 10% by leaving the home. On average, individuals increased their exposure by 23-44% while commuting and conducting activities out of home (compared to the daily concentration at home), regardless of air quality at their home location. We conclude that our proposed dynamic modelling approach significantly improves the results of traditional methods that rely on a long-term average concentration at the home location and we shed light on the importance of using individual daily trajectories to understand exposure.

  18. Monthly average daily global solar radiation in P. D. R. Yemen

    Energy Technology Data Exchange (ETDEWEB)

    Gadhi, S.M.B.; Megdad, R.S.; Albakri, S.A.A. (Aden Univ. (Yemen). Dept. of Mechanical Engineering)

    1991-01-01

    In this paper a study has been made to estimate average global radiation using hours of bright sunshine and measured solar radiation data available for six locations in P.D.R. Yemen. For Aden, data were obtained from Aden Airport. For other locations in P.D.R. Yemen data were obtained from Agricultural Research Center's meteorological sections. Linear regression analysis of the monthly average global radiation and the sunshine duration data of six locations has been performed using the least squares technique. All the above mentioned data have been used in Angstrom's correlation to find the monthly average daily global solar radiation. Results obtained are useful for any solar energy system application in P.D.R. Yemen. (author).

  19. The Effects of the Daily Driven Distance and Age Factor on the Traffic Accidents

    Directory of Open Access Journals (Sweden)

    Figen Ş. KALYONCUOĞLU

    2014-05-01

    Full Text Available Based on Turkish traffic survey data (n=5,520, driver accident rates per million kilometre-driver were compared according to the daily driven distances (DDD for each age group as very old (65+, n=39, old (56-65, n=183, above middle-aged (36-55, n=1,875, middle-aged (26-35, n=2,204, and young (25-, n=1,219. When the accidents-per-km comparison was made in groups matched for daily exposure, there was no evidence of higher risk with increasing age. In all age groups, risk per km decreased with increasing daily driving distance. With this study the accident involvement prediction models have been obtained related to the daily driven distance with and without considering age. These models have been applied to some earlier studies. The results are quite satisfactory. The set of data of this study and the analysis controlling the daily (yearly driving distance might make the “age” effect disappear.

  20. Effects of Lawsonia intracellularis on Average Daily Gain in finisher pigs

    DEFF Research Database (Denmark)

    Johansen, M.; Nielsen, M.; Dahl, J.;

    Lawsonia intracellularis (LI) is the causative agent of porcine proliferative enteropathy1, a disease that is found with high prevalence in all countries with industrial pig production. The infection is known to cause disease in different age groups. In pigs between 6 to 20 weeks of age the endem...... form called Porcine Intestinal Andenomatosis (PIA) is predominant. The clinical signs are diarrhoea, ill-thriftiness and wasting. The objective of this study was to estimate the impact of LI detected in faeces on Average Daily Gain (ADG) in grower-finisher pigs....

  1. Understanding the gap between cognitive abilities and daily living skills in adolescents with autism spectrum disorders with average intelligence.

    Science.gov (United States)

    Duncan, Amie W; Bishop, Somer L

    2015-01-01

    Daily living skills standard scores on the Vineland Adaptive Behavior Scales-2nd edition were examined in 417 adolescents from the Simons Simplex Collection. All participants had at least average intelligence and a diagnosis of autism spectrum disorder. Descriptive statistics and binary logistic regressions were used to examine the prevalence and predictors of a "daily living skills deficit," defined as below average daily living skills in the context of average intelligence quotient. Approximately half of the adolescents were identified as having a daily living skills deficit. Autism symptomatology, intelligence quotient, maternal education, age, and sex accounted for only 10% of the variance in predicting a daily living skills deficit. Identifying factors associated with better or worse daily living skills may help shed light on the variability in adult outcome in individuals with autism spectrum disorder with average intelligence.

  2. Estimation of monthly average daily global solar irradiation using artificial neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Mubiru, J.; Banda, E.J.K.B. [Department of Physics, Makerere University, P.O. Box 7062, Kampala (Uganda)

    2008-02-15

    This study explores the possibility of developing a prediction model using artificial neural networks (ANN), which could be used to estimate monthly average daily global solar irradiation on a horizontal surface for locations in Uganda based on weather station data: sunshine duration, maximum temperature, cloud cover and location parameters: latitude, longitude, altitude. Results have shown good agreement between the estimated and measured values of global solar irradiation. A correlation coefficient of 0.974 was obtained with mean bias error of 0.059 MJ/m{sup 2} and root mean square error of 0.385 MJ/m{sup 2}. The comparison between the ANN and empirical method emphasized the superiority of the proposed ANN prediction model. (author)

  3. Instantaneous-to-daily GPP upscaling schemes based on a coupled photosynthesis-stomatal conductance model: correcting the overestimation of GPP by directly using daily average meteorological inputs.

    Science.gov (United States)

    Wang, Fumin; Gonsamo, Alemu; Chen, Jing M; Black, T Andrew; Zhou, Bin

    2014-11-01

    Daily canopy photosynthesis is usually temporally upscaled from instantaneous (i.e., seconds) photosynthesis rate. The nonlinear response of photosynthesis to meteorological variables makes the temporal scaling a significant challenge. In this study, two temporal upscaling schemes of daily photosynthesis, the integrated daily model (IDM) and the segmented daily model (SDM), are presented by considering the diurnal variations of meteorological variables based on a coupled photosynthesis-stomatal conductance model. The two models, as well as a simple average daily model (SADM) with daily average meteorological inputs, were validated using the tower-derived gross primary production (GPP) to assess their abilities in simulating daily photosynthesis. The results showed IDM closely followed the seasonal trend of the tower-derived GPP with an average RMSE of 1.63 g C m(-2) day(-1), and an average Nash-Sutcliffe model efficiency coefficient (E) of 0.87. SDM performed similarly to IDM in GPP simulation but decreased the computation time by >66%. SADM overestimated daily GPP by about 15% during the growing season compared to IDM. Both IDM and SDM greatly decreased the overestimation by SADM, and improved the simulation of daily GPP by reducing the RMSE by 34 and 30%, respectively. The results indicated that IDM and SDM are useful temporal upscaling approaches, and both are superior to SADM in daily GPP simulation because they take into account the diurnally varying responses of photosynthesis to meteorological variables. SDM is computationally more efficient, and therefore more suitable for long-term and large-scale GPP simulations.

  4. Values of average daily gain of swine posted to commercial hybrids on pork in youth phase depending on the type

    Directory of Open Access Journals (Sweden)

    Diana Marin

    2013-10-01

    Full Text Available Values of average daily gain of weight are calculated according to the ratio of total growth and total number of days of feeding. In the case of the four commercial hybrids intensively exploited was observed, as test applied, that there were no statistically significant differences in terms of average daily gain of these hybrids, but the lowest values ​​of this index were recorded in hybrid B (with Large White as terminal boar.

  5. A preliminary study of the linear relationship between monthly averaged daily solar radiation and daily thermal amplitude in the north of Buenos Aires provence

    CERN Document Server

    Cionco, R; Rodriguez, R

    2012-01-01

    Using irradiance and temperature measurements obtained at the Facultad Regional San Nicol\\'as of UTN, we performed a preliminary study of the linear relationship between monthly averaged daily solar radiation and daily thermal amplitude. The results show a very satisfactory adjustment (R = 0.848, RMS = 0.066, RMS% = 9.690 %), even taking into account the limited number of months (36). Thus, we have a formula of predictive nature, capable of estimating mean monthly solar radiation for various applications. We expect to have new data sets to expand and improve the statistical significance of these results.

  6. Understanding the Gap between Cognitive Abilities and Daily Living Skills in Adolescents with Autism Spectrum Disorders with Average Intelligence

    Science.gov (United States)

    Duncan, Amie W.; Bishop, Somer L.

    2015-01-01

    Daily living skills standard scores on the Vineland Adaptive Behavior Scales-2nd edition were examined in 417 adolescents from the Simons Simplex Collection. All participants had at least average intelligence and a diagnosis of autism spectrum disorder. Descriptive statistics and binary logistic regressions were used to examine the prevalence and…

  7. [The influence of the trematode invasion on the average daily rations and electoral nourishment of Planorbarius corneus (Mollusca: Pulmonata: Bulinidae)].

    Science.gov (United States)

    Stadnichenko, A P; Girin, V K

    2005-01-01

    The influence of the Trematode invasion on the average daily rations and electoral nourishment of the two size groups in the great ramshorn snail Planorbarius corneus, "young" (12-24 mm in diameter) and "old" (24-36.5 mm in diameter), have been investigated.

  8. PREDICTION OF LACTATION YIELD FROM LAST-RECORD DAY AND AVERAGE DAILY YIELD IN NILI-RAVI BUFFALOES

    Directory of Open Access Journals (Sweden)

    M. S. Khan, A. U. Hyder, I. R. Bajwa, M. S. Rehman and F. Hassan

    2005-10-01

    Full Text Available Different adjustment procedures were compared to determine if prediction of lactation milk yield using last record day information could be improved by using information on the average daily milk yield of the recorded lactation. Weekly milk yield records of 993 Nili-Ravi buffaloes for 2704 lactations were used for the study. Comparison of different procedures of lactation milk yield adjustment from partial/incomplete or complete lactations indicated that milk yield predicted from a linear regression equation, or from last test day information, was higher as compared to actual milk yield due to extrapolation to a higher base. Simple linear regression procedure overestimated the yield, especially in the later part of the lactation curve. Most precise adjustments were obtained when last test day and average daily milk yield information were included as predictors. The standard deviation of bias decreased and correlation between actual and predicted lactation milk yield improved with inclusion of average daily milk yield as a predictor along with the last test day milk yield. Last recorded milk yield information along with average daily yield of the recorded lactation period are suggested to be used for standardization of milk yield data in Nili-Ravi buffaloes.

  9. Spatial variations in daily average CO2 concentrations above wetland surface of Xianghai National Nature Reserve, China

    Institute of Scientific and Technical Information of China (English)

    BAI Jun-hong; OUYANG Hua; WANG Qing-gai; ZHOU Cai-ping; XU Xiao-feng

    2005-01-01

    Horizontal and vertical variations of daily average CO2 concentration above the wetland surface were studied in Xianghai National Nature Reserve of China in August, 2000. The primary purpose was to study spatial distribution characteristics of CO2 concentration on the four levels of height(0. 1 m, 0.6 m, 1.2 m and 2 m) and compare the differences of CO2 concentration under different land covers. Results showed that daily average CO2 concentration above wetland surface in Xianghai National Natural Reserve was lower than that above other wetlands in northeast China as well as the worldwide average, suggesting that Xianghai wetland absorbed CO2 in August and acted as"sink" of CO2. The horizontal variations on the four levels of height along the latitude were distinct, and had the changing tendency of"decreasing after increasing" with the increase of height. The areas with obvious variations were consistent on different levels of height,and those with the highest variations appeared above surface of shore, sloping field, Typha wetland and Phragmites wetland; the vertical variations were greatly different, with the higher variations in Phragmites wetland and Typha wetland, and the lands near the shore and the sloping field with the lower variations. Spatial variations of daily average CO2 concentrations above wetland surface were affected by surface qualities and land covers.

  10. Attributes for MRB_E2RF1 Catchments by Major River Basins in the Conterminous United States: 30-Year Average Daily Minimum Temperature, 1971-2000

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This tabular data set represents thecatchment-average for the 30-year (1971-2000) average daily minimum temperature in Celsius multiplied by 100 compiled for every...

  11. The effect of New Neonatal Porcine Diarrhoea Syndrome (NNPDS) on average daily gain and mortality in 4 Danish pig herds

    DEFF Research Database (Denmark)

    Kongsted, Hanne; Stege, Helle; Toft, Nils;

    2014-01-01

    , which is not caused by enterotoxigenic Escherichia coli (ETEC), Clostridium perfringens (C. perfringens) type A/C, Clostridium difficile (C. difficile), rotavirus A, coronavirus, Cystoisospora suis, Strongyloides ransomi, Giardia spp or Cryptosporidium spp. Results: Piglets were estimated to have......Background: The study evaluated the effect of New Neonatal Porcine Diarrhoea Syndrome (NNPDS) on average daily gain (ADG) and mortality and described the clinical manifestations in four herds suffering from the syndrome. NNPDS is a diarrhoeic syndrome affecting piglets within the first week of life...... of diarrhoea on mortality, but herd of origin, sow parity, birth weight, and gender were significantly associated with mortality. In one of the herds, approximately 25% of the diarrhoeic piglets vs. 6% of the non-diarrhoeic piglets died, and 74% of necropsied piglets were diagnosed with enteritis...

  12. Estimation of the monthly average daily solar radiation using geographic information system and advanced case-based reasoning.

    Science.gov (United States)

    Koo, Choongwan; Hong, Taehoon; Lee, Minhyun; Park, Hyo Seon

    2013-05-07

    The photovoltaic (PV) system is considered an unlimited source of clean energy, whose amount of electricity generation changes according to the monthly average daily solar radiation (MADSR). It is revealed that the MADSR distribution in South Korea has very diverse patterns due to the country's climatic and geographical characteristics. This study aimed to develop a MADSR estimation model for the location without the measured MADSR data, using an advanced case based reasoning (CBR) model, which is a hybrid methodology combining CBR with artificial neural network, multiregression analysis, and genetic algorithm. The average prediction accuracy of the advanced CBR model was very high at 95.69%, and the standard deviation of the prediction accuracy was 3.67%, showing a significant improvement in prediction accuracy and consistency. A case study was conducted to verify the proposed model. The proposed model could be useful for owner or construction manager in charge of determining whether or not to introduce the PV system and where to install it. Also, it would benefit contractors in a competitive bidding process to accurately estimate the electricity generation of the PV system in advance and to conduct an economic and environmental feasibility study from the life cycle perspective.

  13. Occurrence of aflatoxin M1 in human milk samples in Vojvodina, Serbia: Estimation of average daily intake by babies.

    Science.gov (United States)

    Radonić, Jelena R; Kocić Tanackov, Sunčica D; Mihajlović, Ivana J; Grujić, Zorica S; Vojinović Miloradov, Mirjana B; Škrinjar, Marija M; Turk Sekulić, Maja M

    2017-01-02

    The objectives of the study were to determine the aflatoxin M1 content in human milk samples in Vojvodina, Serbia, and to assess the risk of infants' exposure to aflatoxins food contamination. The growth of Aspergillus flavus and production of aflatoxin B1 in corn samples resulted in higher concentrations of AFM1 in milk and dairy products in 2013, indicating higher concentrations of AFM1 in human milk samples in 2013 and 2014 in Serbia. A total number of 60 samples of human milk (colostrum and breast milk collected 4-8 months after delivery) were analyzed for the presence of AFM1 using the Enzyme Linked Immunosorbent Assay method. The estimated daily intake of AFM1 through breastfeeding was calculated for the colostrum samples using an average intake of 60 mL/kg body weight (b.w.)/day on the third day of lactation. All breast milk collected 4-8 months after delivery and 36.4% of colostrum samples were contaminated with AFM1. The greatest percentage of contaminated colostrum (85%) and all samples of breast milk collected 4-8 months after delivery had AFM1 concentration above maximum allowable concentration according to the Regulation on health safety of dietetic products. The mean daily intake of AFM1 in colostrum was 2.65 ng/kg bw/day. Results of our study indicate the high risk of infants' exposure, who are at the early stage of development and vulnerable to toxic contaminants.

  14. Effects of dam parity and pre-weaning average daily gain of Holstein calves on future milk production.

    Science.gov (United States)

    Hoseyni, Fatemeh; Mahjoubi, Ehsan; Zahmatkesh, Davood; Yazdi, Mehdi Hossein

    2016-11-01

    This research communication describes relationships between pre-weaning average daily gain (ADG) and dam parity with future productivity of dairy calves. Higher ADG before weaning has been shown to be related to greater milk production in the first lactation of Holstein calves fed milk replacer. However, data is limited on the relationship between pre-weaning ADG and first lactation performance of Holstein calves fed whole milk. Data of three hundred and thirty-two Holstein calves from 35 primiparous and 297 multiparous cows was investigated to evaluate the relationship between the dam parity and pre-weaning ADG with the first lactation performance. Results indicated that birth (P primiparous or multiparous cows, although milk yield tended to be higher in the former and ADG higher in the latter. Correlations between 305 d milk yield and pre-weaning ADG, dam parity and birth body weight were low and non-significant, although there was a tendency for a positive correlation between ADG and milk yield.

  15. A randomised clinical trial on the efficacy of oxytetracycline dose through water medication of nursery pigs on diarrhoea, faecal shedding of Lawsonia intracellularis and average daily weight gain

    DEFF Research Database (Denmark)

    Larsen, Inge-Lise; Hjulsager, Charlotte Kristiane; Holm, Anders;

    2016-01-01

    the efficacy of three oral dosage regimens (5, 10 and 20mg/kg body weight) of oxytetracycline (OTC) in drinking water over a five-day period on diarrhoea, faecal shedding of LI and average daily weight gain (ADG). A randomised clinical trial was carried out in four Danish pig herds. In total, 539 animals from...

  16. Analysis of Yearly Traffic Fluctuation on Latvian Highways

    Science.gov (United States)

    Freimanis, A.; Paeglı¯tis, A.

    2015-11-01

    Average annual daily traffic and average annual truck traffic are two most used metrics for road management decisions. They are calculated from data gathered by continuous counting stations embedded in road pavement, manual counting sessions or mobile counting devices. Last two usually do not last longer than a couple of weeks so the information gathered is influenced by yearly traffic fluctuations. Data containing a total of 8,186,871 vehicles or 1989 days from 4 WIM stations installed on highways in Latvia were used in this study. Each of the files was supposed to contain data from only 1 day and additional data were deleted. No other data cleaning steps were performed, which increased the number of vehicles as counting systems sometimes split vehicles into two. Weekly traffic and weekly truck traffic was normalized against respective average values. Each weekly value was then plotted against its number in a year for better visual perception. Weekly traffic amplitudes were used to assess differences between different locations and standard deviations for fluctuation comparison of truck and regular traffic at the same location. Results show that truck traffic fluctuates more than regular traffic during a year, especially around holidays. Differences between counting locations were larger for regular traffic than truck traffic. These results show that average annual daily traffic could be influenced more if short term counting results are adjusted by factors derived from unsuitable continuous counting stations, but truck traffic is more influenced by the time of year in which counting is done.

  17. Using remotely sensed data to estimate area-averaged daily surface fluxes over a semi-arid mixed agricultural land

    OpenAIRE

    2008-01-01

    Optical remote sensing has been widely used for diagnostics of land surface atmosphere exchanges, including evapotranspiration (ET). Estimating ET now benefits from modeling maturity at local scale, while ongoing challenges include both spatial and temporal issues: influences of spatial heterogeneities on non-linear behavior when upscaling and extrapolation of instantaneous estimates at satellite overpass to the daily scale. Both issues are very important when using remote sensing for managin...

  18. Attributes for NHDPlus Catchments (Version 1.1) for the Conterminous United States: Average Annual Daily Maximum Temperature, 2002

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set represents the average monthly maximum temperature in Celsius multiplied by 100 for 2002 compiled for every catchment of NHDPlus for the conterminous...

  19. Attributes for NHDPlus Catchments (Version 1.1) for the Conterminous United States: Average Annual Daily Minimum Temperature, 2002

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set represents the average monthly minimum temperature in Celsius multiplied by 100 for 2002 compiled for every catchment of NHDPlus for the conterminous...

  20. ANALYSIS OF THE STATISTICAL BEHAVIOUR OF DAILY MAXIMUM AND MONTHLY AVERAGE RAINFALL ALONG WITH RAINY DAYS VARIATION IN SYLHET, BANGLADESH

    Directory of Open Access Journals (Sweden)

    G. M. J. HASAN

    2014-10-01

    Full Text Available Climate, one of the major controlling factors for well-being of the inhabitants in the world, has been changing in accordance with the natural forcing and manmade activities. Bangladesh, the most densely populated countries in the world is under threat due to climate change caused by excessive use or abuse of ecology and natural resources. This study checks the rainfall patterns and their associated changes in the north-eastern part of Bangladesh mainly Sylhet city through statistical analysis of daily rainfall data during the period of 1957 - 2006. It has been observed that a good correlation exists between the monthly mean and daily maximum rainfall. A linear regression analysis of the data is found to be significant for all the months. Some key statistical parameters like the mean values of Coefficient of Variability (CV, Relative Variability (RV and Percentage Inter-annual Variability (PIV have been studied and found to be at variance. Monthly, yearly and seasonal variation of rainy days also analysed to check for any significant changes.

  1. High average daily intake of PCDD/Fs and serum levels in residents living near a deserted factory producing pentachlorophenol (PCP) in Taiwan: Influence of contaminated fish consumption

    Energy Technology Data Exchange (ETDEWEB)

    Lee, C.C. [Department of Environmental and Occupational Health, Medical College, National Cheng Kung University, Tainan, Taiwan (China); Research Center of Environmental Trace Toxic Substances, Medical College, National Cheng Kung University, Tainan, Taiwan (China); Lin, W.T. [Department of Environmental and Occupational Health, Medical College, National Cheng Kung University, Tainan, Taiwan (China); Liao, P.C. [Department of Environmental and Occupational Health, Medical College, National Cheng Kung University, Tainan, Taiwan (China); Research Center of Environmental Trace Toxic Substances, Medical College, National Cheng Kung University, Tainan, Taiwan (China); Su, H.J. [Department of Environmental and Occupational Health, Medical College, National Cheng Kung University, Tainan, Taiwan (China); Research Center of Environmental Trace Toxic Substances, Medical College, National Cheng Kung University, Tainan, Taiwan (China); Chen, H.L. [Department of Industrial Safety and Health, Hung Kuang University, Taichung, 34 Chung Chie Rd. Sha Lu, Taichung 433, Taiwan (China)]. E-mail: hsiulin@sunrise.hk.edu.tw

    2006-05-15

    An abandoned pentachlorophenol plant and nearby area in southern Taiwan was heavily contaminated by dioxins, impurities formed in the PCP production process. The investigation showed that the average serum PCDD/Fs of residents living nearby area (62.5 pg WHO-TEQ/g lipid) was higher than those living in the non-polluted area (22.5 and 18.2 pg WHO-TEQ/g lipid) (P < 0.05). In biota samples, average PCDD/F of milkfish in sea reservoir (28.3 pg WHO-TEQ/g) was higher than those in the nearby fish farm (0.15 pg WHO-TEQ/g), and Tilapia and shrimp showed the similar trend. The average daily PCDD/Fs intake of 38% participants was higher than 4 pg WHO-TEQ/kg/day suggested by the world health organization. Serum PCDD/F was positively associated with average daily intake (ADI) after adjustment for age, sex, BMI, and smoking status. In addition, a prospective cohort study is suggested to determine the long-term health effects on the people living near factory. - Inhabitants living near a deserted PCP factory are exposed to high PCDD/F levels.

  2. Statistical comparison of models for estimating the monthly average daily diffuse radiation at a subtropical African site

    Energy Technology Data Exchange (ETDEWEB)

    Bashahu, M. [University of Burundi, Bujumbura (Burundi). Institute of Applied Pedagogy, Department of Physics and Technology

    2003-07-01

    Nine correlations have been developed in this paper to estimate the monthly average diffuse radiation for Dakar, Senegal. A 16-year period data on the global (H) and diffuse (H{sub d}) radiation, together with data on the bright sunshine hours (N), the fraction of the sky's (Ne/8), the water vapour pressure in the air (e) and the ambient temperature (T) have been used for that purpose. A model inter-comparison based on the MBE, RMSE and t statistical tests has shown that estimates in any of the obtained correlations are not significantly different from their measured counterparts, thus all the nine models are recommended for the aforesaid location. Three of them should be particularly selected for their simplicity, universal applicability and high accuracy. Those are simple linear correlations between K{sub d} and N/N{sub d}, Ne/8 or K{sub t}. Even presenting adequate performance, the remaining correlations are either simple but less accurate, or multiple or nonlinear regressions needing one or two input variables. (author)

  3. A meta-analysis comparing the effect of PCV2 vaccines on average daily weight gain and mortality rate in pigs from weaning to slaughter.

    Science.gov (United States)

    Kristensen, Charlotte Sonne; Baadsgaard, Niels Peter; Toft, Nils

    2011-03-01

    The aim of this investigation was, through a meta-analysis, to review the published literature concerning the effect of PCV2 vaccination on the average daily weight gain (ADG) and on the mortality rate in pigs from weaning to slaughter. The review was restricted to studies investigating the effect of vaccines against PCV2 published from 2006 to 2008, identified using computerised literature databases. Only studies that met the following criteria were included: commercial vaccines were used, pigs or pens were assigned randomly to vaccination versus control groups in herds naturally infected with PCV2, and vaccinated and non-vaccinated pigs were housed together. Furthermore, it was a requirement that sample size, age at vaccination, and production period were stated. The levels of ADG and mortality rate had to be comparable to those seen in modern intensive swine production. In total, 107 studies were identified; 70 were excluded because they did not fulfil the inclusion criteria and 13 were identical to results published elsewhere. A significant effect of PCV2 vaccination on ADG was found for pigs in all production phases. The largest increase in ADG was found for finishing pigs (41.5g) and nursery-finishing pigs (33.6g) with only 10.6g increase in the nursery pigs. Mortality rate was significantly reduced for finishing pigs (4.4%) and nursery-finishing pigs (5.4%), but not for nursery pigs (0.25%). Herds negative for PRRS had a significantly larger increase in ADG compared to herds positive for PRRS. The PRRS status had no effect on mortality rate.

  4. Molecular characterization of the porcine JHDM1A gene associated with average daily gain: evaluation its role in skeletal muscle development and growth.

    Science.gov (United States)

    Peng, Yong-Bo; Fan, Bin; Han, Xue-Lei; Xu, Xue-Wen; Rothschild, Max F; Yerle, Martine; Liu, Bang

    2011-10-01

    JHDM1A, a member of the JHDM (JmjC-domain-containing histone demethylase) family, plays an central role in gene silencing, cell cycle, cell growth and cancer development through histone H3K36 demethylation modification. Here reported the cloning, expression, chromosomal location and association analysis with growth traits of porcine JHDM1A gene. Sequence analysis showed that the porcine JHDM1A gene encodes 1,162 amino acids and contains JmjC, F-box, and CXXC zinc-finger domains, which coding sequence and deduced protein shares 91 and 99% similarity with human JHDM1A, respectively. Spatio-Temporal expression analysis indicated that the mRNA expression of porcine JHDM1A had significantly higher levels in the middle (65 days) and later (90 days) period's embryo skeletal muscle than that of 33 days, and showed a ubiquitously expression but with the highest abundance in kidney, lung and liver of an adult pig. Radiation hybrid mapping and the following linkage mapping data indicate that JHDM1A maps to 2p17 region of pig chromosome 2 (SSC2). Allele frequency differences were detected in different pig breeds and an association study was performed with a SNP within 3'UTR. The results showed that there is a tendency for allele frequencies to differ between the fast growth breeds (Yorkshire) and slow growth pig breeds (Qingping pigs, Yushan Black pigs, Erhualian pigs and Dahuabai pigs). The association analysis using a Berkshire × Yorkshire F(2) population indicated that the C224G polymorphism had a highly significant association with average daily gain on test (P growth and quality traits.

  5. Evaluation of Potential Average Daily Doses (ADDs) of PM2.5 for Homemakers Conducting Pan-Frying Inside Ordinary Homes under Four Ventilation Conditions

    Science.gov (United States)

    Lee, Seonyeop; Yu, Sol; Kim, Sungroul

    2017-01-01

    Several studies reported that commercial barbecue restaurants likely contribute to the indoor emission of particulate matters with a diameter of 2.5 micrometers or less (PM2.5) while pan-frying meat. However, there is inadequate knowledge of exposure level to indoor PM2.5 in homes and the contribution of a typical indoor pan-frying event. We measured the indoor PM2.5 concentration and, using Monte-Carlo simulation, estimated potential average daily dose (ADD) of PM2.5 for homemakers pan-frying a piece of pork inside ordinary homes. Convenience-based sampling at 13 homes was conducted over four consecutive days in June 2013 (n = 52). Although we pan-fried 100 g pork for only 9 min, the median (interquartile range, IQR) value was 4.5 (2.2–5.6) mg/m3 for no ventilation and 0.5 (0.1–1.3) mg/m3 with an active stove hood ventilation system over a 2 h sampling interval. The probabilities that the ADDs from inhalation of indoor PM2.5 would be higher than the ADD from inhalation of PM2.5 on an outdoor roadside (4.6 μg/kg·day) were 99.44%, 97.51%, 93.64%, and 67.23%, depending on the ventilation conditions: (1) no window open; (2) one window open in the kitchen; (3) two windows open, one each in the kitchen and living room; and (4) operating a forced-air stove hood, respectively. PMID:28098788

  6. Associations between age at first calving, rearing average daily weight gain, herd milk yield and dairy herd production, reproduction, and profitability.

    Science.gov (United States)

    Krpálková, L; Cabrera, V E; Kvapilík, J; Burdych, J; Crump, P

    2014-10-01

    The objective of this study was to evaluate the associations of variable intensity in rearing dairy heifers on 33 commercial dairy herds, including 23,008 cows and 18,139 heifers, with age at first calving (AFC), average daily weight gain (ADG), and milk yield (MY) level on reproduction traits and profitability. Milk yield during the production period was analyzed relative to reproduction and economic parameters. Data were collected during a 1-yr period (2011). The farms were located in 12 regions in the Czech Republic. The results show that those herds with more intensive rearing periods had lower conception rates among heifers at first and overall services. The differences in those conception rates between the group with the greatest ADG (≥0.800 kg/d) and the group with the least ADG (≤0.699 kg/d) were approximately 10 percentage points in favor of the least ADG. All the evaluated reproduction traits differed between AFC groups. Conception at first and overall services (cows) was greatest in herds with AFC ≥800 d. The shortest days open (105 d) and calving interval (396 d) were found in the middle AFC group (799 to 750 d). The highest number of completed lactations (2.67) was observed in the group with latest AFC (≥800 d). The earliest AFC group (≤749 d) was characterized by the highest depreciation costs per cow at 8,275 Czech crowns (US$414), and the highest culling rate for cows of 41%. The most profitable rearing approach was reflected in the middle AFC (799 to 750 d) and middle ADG (0.799 to 0.700 kg) groups. The highest MY (≥8,500 kg) occurred with the earliest AFC of 780 d. Higher MY led to lower conception rates in cows, but the highest MY group also had the shortest days open (106 d) and a calving interval of 386 d. The same MY group had the highest cow depreciation costs, net profit, and profitability without subsidies of 2.67%. We conclude that achieving low AFC will not always be the most profitable approach, which will depend upon farm

  7. Lagrangian Multi-Class Traffic State Estimation

    OpenAIRE

    Yuan, Y.

    2013-01-01

    Road traffic is important to everybody in the world. People travel and commute everyday. For those who travel by cars (or other types of road vehicles), traffic congestion is a daily experience. One essential goal of traffic researchers is to reduce traffic congestion and to improve the whole traffic system operation and the environment. To achieve this goal, we have to first understand prevailing traffic situations, then perform pro-active traffic control and management. The estimation of tr...

  8. Predictability of road traffic and congestion in urban areas.

    Science.gov (United States)

    Wang, Jingyuan; Mao, Yu; Li, Jing; Xiong, Zhang; Wang, Wen-Xu

    2015-01-01

    Mitigating traffic congestion on urban roads, with paramount importance in urban development and reduction of energy consumption and air pollution, depends on our ability to foresee road usage and traffic conditions pertaining to the collective behavior of drivers, raising a significant question: to what degree is road traffic predictable in urban areas? Here we rely on the precise records of daily vehicle mobility based on GPS positioning device installed in taxis to uncover the potential daily predictability of urban traffic patterns. Using the mapping from the degree of congestion on roads into a time series of symbols and measuring its entropy, we find a relatively high daily predictability of traffic conditions despite the absence of any priori knowledge of drivers' origins and destinations and quite different travel patterns between weekdays and weekends. Moreover, we find a counterintuitive dependence of the predictability on travel speed: the road segment associated with intermediate average travel speed is most difficult to be predicted. We also explore the possibility of recovering the traffic condition of an inaccessible segment from its adjacent segments with respect to limited observability. The highly predictable traffic patterns in spite of the heterogeneity of drivers' behaviors and the variability of their origins and destinations enables development of accurate predictive models for eventually devising practical strategies to mitigate urban road congestion.

  9. High average daily intake of PCDD/Fs and serum levels in residents living near a deserted factory producing pentachlorophenol (PCP) in Taiwan: influence of contaminated fish consumption

    Energy Technology Data Exchange (ETDEWEB)

    Lee Ching-Chang; Lin Wu-Ting; Liao Po-Chi; Su Huey-Jen [Dept. of Environmental and Occupational Health/Research Center of Environmental Trace Toxic substances, Medical Coll., National Cheng Kung Univ., Tainan (Taiwan); Chen Hsiu-Lin [Inst. of Basic Medical Sciences, Medical Coll., National Cheng Kung Univ., Tainan (Taiwan)

    2004-09-15

    Many reports have suggested that PCDD/Fs (polychlorinated dibenzo-p-dioxins and dibenzofurans) contribute to immune deficiency, liver damage, human carcinogenesis, and neuromotor maturation in children. Therefore, beginning in 1999, the Taiwan Environmental Protection Agency (EPA) conducted a survey to determine serum levels of PCDD/Fs in the general populations living around 19 incinerators in Taiwan. Relatively high average serum PCDD/F levels were unexpectedly found in Tainan city, a less industrialized area in southwestern Taiwan, than in other urban areas. We therefore reviewed the usage history of the land and found that a factory situated between Hsien-Gong Li and Lu-Erh Li, two administrative units of Tainan city, had been manufacturing pentachlorophenol (PCP) between 1967 and 1982. PCDD/Fs are formed as byproducts in the PCP manufacturing process. Exposure to PCP and its derivatives via the food chain is the most significant intake route of PCDD/Fs in consumers in the European Union (EU). In Japan, in addition to combustion processes, PCP and chlornitrofen (CNP) have also been identified as the major sources of PCDD/Fs in Tokyo Bay7. A preliminary investigation showed that the soil in the PCP factory and sediments in the sea reservoir (13 hectares) near the deserted factory were seriously contaminated with PCDD/Fs (260-184,000 and 20-6220 pg I-TEQ/g, respectively), levels higher than those in other countries. Therefore, the aim of this study was to compare the PCDD/F levels of fish meat in the sea reservoir and the serum in inhabitants living in the vicinity of the closed PCP plant and other nearby areas. The data from human and other biota samples might clarify the transmission pathway of the PCDD/F contaminants from the PCP factory to local residents, provide information about the exposure status of those living in the vicinity of the deserted PCP factory, and also lead to useful suggestions for controlling PCDD/F accumulation in those living near such

  10. An environmental, economic, and social assessment of improving cattle finishing weight or average daily gain within U.S. beef production.

    Science.gov (United States)

    White, R R; Capper, J L

    2013-12-01

    The objective of this study was to assess environmental impact, economic viability, and social acceptability of 3 beef production systems with differing levels of efficiency. A deterministic model of U.S. beef production was used to predict the number of animals required to produce 1 × 10(9) kg HCW beef. Three production treatments were compared, 1 representing average U.S. production (control), 1 with a 15% increase in ADG, and 1 with a 15% increase in finishing weight (FW). For each treatment, various socioeconomic scenarios were compared to account for uncertainty in producer and consumer behavior. Environmental impact metrics included feed consumption, land use, water use, greenhouse gas emissions (GHGe), and N and P excretion. Feed cost, animal purchase cost, animal sales revenue, and income over costs (IOVC) were used as metrics of economic viability. Willingness to pay (WTP) was used to identify improvements or reductions in social acceptability. When ADG improved, feedstuff consumption, land use, and water use decreased by 6.4%, 3.2%, and 12.3%, respectively, compared with the control. Carbon footprint decreased 11.7% and N and P excretion were reduced by 4% and 13.8%, respectively. When FW improved, decreases were seen in feedstuff consumption (12.1%), water use (9.2%). and land use (15.5%); total GHGe decreased 14.7%; and N and P excretion decreased by 10.1% and 17.2%, compared with the control. Changes in IOVC were dependent on socioeconomic scenario. When the ADG scenario was compared with the control, changes in sector profitability ranged from 51 to 117% (cow-calf), -38 to 157% (stocker), and 37 to 134% (feedlot). When improved FW was compared, changes in cow-calf profit ranged from 67% to 143%, stocker profit ranged from -41% to 155% and feedlot profit ranged from 37% to 136%. When WTP was based on marketing beef being more efficiently produced, WTP improved by 10%; thus, social acceptability increased. When marketing was based on production

  11. Lagrangian Multi-Class Traffic State Estimation

    NARCIS (Netherlands)

    Yuan, Y.

    2013-01-01

    Road traffic is important to everybody in the world. People travel and commute everyday. For those who travel by cars (or other types of road vehicles), traffic congestion is a daily experience. One essential goal of traffic researchers is to reduce traffic congestion and to improve the whole traffi

  12. 兰州市日均气温对荨麻疹发病的滞后效应研究%Lag effect of daily average temperature on the occurrence of urticaria in Lanzhou city

    Institute of Scientific and Technical Information of China (English)

    石春蕊; 熊潇; 潘亚娟; 董继元; 骆志成; 郗群; 王亚婷

    2016-01-01

    Objective To evaluate effects of daily average temperature on the occurrence of urticaria in Lanzhou city,and to analyze differences in the effects between different populations.Methods Time-series data on daily outpatient visits for urticaria between January 1,2007 and December 31,2013 were collected from the First Hospital of Lanzhou University and Lanzhou University Second Hospital.Daily meteorological data during this peroid were obtained from the Gansu Meteorological Bureau.Distributed lag non-linear models were used to analyze the association between daily average temperature and occurrence of urticaria,and the analysis was stratified by age and gender.Results The association between daily average temperature and daily number of outpatient visits for urticaria was nonlinear.Low temperature had significant lag effects on the daily number of outpatient visits for urticaria,with the maximum relative risk (RR) value (1.014 [95% CI 1.000-1.023]) observed at 6 ℃ on lag day 18.Stratification analysis demonstrated that the effects of high temperature on the number of outpatient visits for urticaria were apparent on the day of exposure in age groups of 0-18 and 19-64 years,but decreased on the day of exposure in the age group ≥ 65 years.The effects of low temperature,which showed similar trends along with the increment of lag days in all groups,were relatively delayed and occurred 2 to 4 days after exposure.Conclusions Air temperature affects the occurrence of urticaria in Lanzhou city.Low temperature has evident lag effects on the occurrence of urticaria,while high temperature does not have.%目的 探讨兰州市日均气温对荨麻疹发病的影响,以及不同人群中的差异.方法 收集兰州大学第一、二医院皮肤科2007年1月1日至2013年12月31日,荨麻疹就诊人数的时间序列资料和相应的气象资料,运用分布滞后非线性模型分析气温与荨麻疹发病的关系,并按性别和年龄进行分层分析.结果 日均

  13. Demand-oriented traffic management for incidents and disasters

    OpenAIRE

    Flötteröd, Yun-Pang; Bieker, Laura

    2012-01-01

    Traffic simulation has been extensively used as a decision support tool for efficient traffic management in daily life. During disasters and incidents, traffic simulation can further help rescue teams to understand the current traffic state and the possible impacts of proposed strategies and then to make proper decisions. At this point, the changes in traffic demand should also be considered in the simulation to reflect the latest traffic state. In this paper, a demand-oriented traffic manage...

  14. Batch medication of intestinal infections in nursery pigs—A randomised clinical trial on the efficacy of treatment strategy, type of antibiotic and bacterial load on average daily weight gain

    DEFF Research Database (Denmark)

    Weber, Nicolai Rosager; Pedersen, Ken Steen; Hansen, Christian Fink;

    2017-01-01

    after weaning) on average daily weight gain (ADG); (2) to compare the effect of treatment with doxycycline or tylosine on diarrhoea prevalence, pathogenic bacterial load, and ADG; (3) to evaluate PCR testing of faecal pen floor samples as a diagnostic tool for determining the optimal time of treatment...... difference (p = 0.04) of mean diarrhoea prevalence on day 21 of the study between pens treated with tylosine (0.254, 95% CI: 0.184–0.324), and doxycycline (0.167, 95% CI: 0.124–0.210). The type of antibiotic compound was not found to have a significant effect on ADG (p = 0.209). (3) Pigs starting treatment...... was achieved when treatment was initiated 14 days after weaning in pens where intestinal pathogens were detected. Doxycycline was more effective in reducing diarrhoea and LI excretion levels than treatment with tylosine....

  15. EVALUATION OF THE AVERAGE DAILY DIETARY INTAKES OF BIOTINS IN CHINESE RESIDENTS%中国居民膳食生物素平均每日摄入量评估

    Institute of Scientific and Technical Information of China (English)

    王竹; 杨晶明; 向雪松; 杨月欣

    2013-01-01

    目的 采用食物分类计算法评估中国居民膳食生物素平均摄入量.方法 448种食物,采用微生物法测定生物素含量后,根据2002年中国居民营养与健康状况调查报告分为31类,计算各类食物算术均值和几何均值,乘以相应的食物消费量加和计算城乡居民和2岁以上各年龄段人群生物素平均摄入量.结果 全国居民总体生物素摄入量(算术均值)为40.O μg/d,城乡范围36.8~48.9 μg/d,几何均值计算结果比算术均值约低9μg/d.30岁前生物素摄入量随年龄增加,到30~45岁时达到最高;其中女性(38.7 μg/d)低于男性(43.8 μg/d);45岁后随老龄化生物量摄入逐渐下降,70岁时女性仅为31.2 μg/d(算术均值).结论 我国城乡居民膳食生物素平均摄入量基本可以达到中国营养学会推荐营养素适宜摄入量(AI),育龄妇女和老年妇女生物素摄入量相对偏低.%Objective To estimate the average dietary intakes of biotin using food classification calculation in Chinese. Method Four hundred and forty-eight individual foods with biotin content measured by microbiological method were divided into 31 groups. The daily intakes of biotin in urban and rural residents over 2 years old were calculated, based on the arithmetic mean and geometric mean contents of biotin in different food groups, multiplied by the amount of foods intake reported by China National Nutrition and Health Survey 2002. Results The average daily intake of biotin by arithmetic mean for overall residents were 40.0 μg/d, ranged from 36.8 to 48.9 μg/d. The results calculated by geometric mean showed 9 ug/d less. For different age stages, the daily biotin intakes increased with age and topped around 30-45 years old. The average intake was less in women (38.7 μg/d) than men (43.8 μg/d). The biotin intake was only 31.2 μg/d by women over 70 years old. Conclusion The average intake of dietary biotin in Chinese residents basically achieved the adequate

  16. A Traffic Forecasting Method with Function to Control Residual Error Distribution for IP Access Networks

    Science.gov (United States)

    Kitahara, Takeshi; Furuya, Hiroki; Nakamura, Hajime

    Since traffic in IP access networks is less aggregated than in backbone networks, its variance could be significant and its distribution may be long-tailed rather than Gaussian in nature. Such characteristics make it difficult to forecast traffic volume in IP access networks for appropriate capacity planning. This paper proposes a traffic forecasting method that includes a function to control residual error distribution in IP access networks. The objective of the proposed method is to grasp the statistical characteristics of peak traffic variations, while conventional methods focus on average rather than peak values. In the proposed method, a neural network model is built recursively while weighting residual errors around the peaks. This enables network operators to control the trade-off between underestimation and overestimation errors according to their planning policy. Evaluation with a total of 136 daily traffic volume data sequences measured in actual IP access networks demonstrates the performance of the proposed method.

  17. State Averages

    Data.gov (United States)

    U.S. Department of Health & Human Services — A list of a variety of averages for each state or territory as well as the national average, including each quality measure, staffing, fine amount and number of...

  18. Traffic Monitoring without single Car Detection from optical airborne Images

    OpenAIRE

    Zeller, Klaus; Hinz, Stefan; Rosenbaum, Dominik; Leitloff, Jens; Reinartz, Peter

    2009-01-01

    This article describes several methods for traffic monitoring from airborne optical remote sensing data. These methods classify the traffic into free flowing traffic, traffic congestion and traffic jam. Furthermore a method is explained, which provides information about the average speed of dense traffic on a defined part of the road. All methods gather the information directly from image features, without the use of single vehicle detection. The classification of the traffic is done by st...

  19. Temporal variation of traffic on highways and the development of accurate temporal allocation factors for air pollution analyses

    Science.gov (United States)

    Batterman, Stuart; Cook, Richard; Justin, Thomas

    2015-04-01

    Traffic activity encompasses the number, mix, speed and acceleration of vehicles on roadways. The temporal pattern and variation of traffic activity reflects vehicle use, congestion and safety issues, and it represents a major influence on emissions and concentrations of traffic-related air pollutants. Accurate characterization of vehicle flows is critical in analyzing and modeling urban and local-scale pollutants, especially in near-road environments and traffic corridors. This study describes methods to improve the characterization of temporal variation of traffic activity. Annual, monthly, daily and hourly temporal allocation factors (TAFs), which describe the expected temporal variation in traffic activity, were developed using four years of hourly traffic activity data recorded at 14 continuous counting stations across the Detroit, Michigan, U.S. region. Five sites also provided vehicle classification. TAF-based models provide a simple means to apportion annual average estimates of traffic volume to hourly estimates. The analysis shows the need to separate TAFs for total and commercial vehicles, and weekdays, Saturdays, Sundays and observed holidays. Using either site-specific or urban-wide TAFs, nearly all of the variation in historical traffic activity at the street scale could be explained; unexplained variation was attributed to adverse weather, traffic accidents and construction. The methods and results presented in this paper can improve air quality dispersion modeling of mobile sources, and can be used to evaluate and model temporal variation in ambient air quality monitoring data and exposure estimates.

  20. No evidence of a threshold in traffic volume affecting road-kill mortality at a large spatio-temporal scale

    Energy Technology Data Exchange (ETDEWEB)

    Grilo, Clara, E-mail: clarabentesgrilo@gmail.com [Departamento de Biología de la Conservación, Estación Biológica de Doñana (EBD-CSIC), Calle Américo Vespucio s/n, E-41092 Sevilla (Spain); Centro Brasileiro de Estudos em Ecologia de Estradas, Departamento de Biologia, Universidade Federal de Lavras, Campus Universitário, 37200-000 Lavras, Minas Gerais (Brazil); Ferreira, Flavio Zanchetta; Revilla, Eloy [Departamento de Biología de la Conservación, Estación Biológica de Doñana (EBD-CSIC), Calle Américo Vespucio s/n, E-41092 Sevilla (Spain)

    2015-11-15

    Previous studies have found that the relationship between wildlife road mortality and traffic volume follows a threshold effect on low traffic volume roads. We aimed at evaluating the response of several species to increasing traffic intensity on highways over a large geographic area and temporal period. We used data of four terrestrial vertebrate species with different biological and ecological features known by their high road-kill rates: the barn owl (Tyto alba), hedgehog (Erinaceus europaeus), red fox (Vulpes vulpes) and European rabbit (Oryctolagus cuniculus). Additionally, we checked whether road-kill likelihood varies when traffic patterns depart from the average. We used annual average daily traffic (AADT) and road-kill records observed along 1000 km of highways in Portugal over seven consecutive years (2003–2009). We fitted candidate models using Generalized Linear Models with a binomial distribution through a sample unit of 1 km segments to describe the effect of traffic on the probability of finding at least one victim in each segment during the study. We also assigned for each road-kill record the traffic of that day and the AADT on that year to test for differences using Paired Student's t-test. Mortality risk declined significantly with traffic volume but varied among species: the probability of finding road-killed red foxes and rabbits occurs up to moderate traffic volumes (< 20,000 AADT) whereas barn owls and hedgehogs occurred up to higher traffic volumes (40,000 AADT). Perception of risk may explain differences in responses towards high traffic highway segments. Road-kill rates did not vary significantly when traffic intensity departed from the average. In summary, we did not find evidence of traffic thresholds for the analysed species and traffic intensities. We suggest mitigation measures to reduce mortality be applied in particular on low traffic roads (< 5000 AADT) while additional measures to reduce barrier effects should take into

  1. pH对大菱鲆幼鱼平均日增重及鳃显微结构的影响%Effects of pH on Average Daily Growth Rate and Gill Microstructure of Juvenile Scophthalmus maximus

    Institute of Scientific and Technical Information of China (English)

    王双耀; 毛守康; 苗治欧; 姜志强; 杨晶晶; 温施慧; 姚恩长

    2013-01-01

    The average daily growth rate (AGR) and the microstructure of the gill of juvenile turbot (Scophthalmus maximus) were examined under different pH levels. The results show that the AGR decreased with increasing pH levels, and the AGR of pH 8.3 and 8.8 groups were significantly lower than that of other treatment groups (P<0.05). When the fish was exposed to pH 6.3, the lamellar epithelia were keratinized severely, no significant changes in lamellar epithelia were observed from pH 6.8 to 7.8, keratinization and lifting were found in the lamellar epithelia at pH 8.3, and the keratinization was more severe at pH 8.8. The results suggest that pH 6.8~7.8 is considered as the optimum ranges for juvenile turbot.%研究不同pH对大菱鲆(Scophthalmus maximus)幼鱼平均日增重及鳃显微结构的影响。结果显示:大菱鲆平均日增重随pH升高而降低,pH 8.3和8.8组平均日增重显著低于其他处理组(P<0.05)。pH 6.3时鳃小片上皮细胞角质化较为严重;pH 6.8和7.8时鳃上皮细胞未见明显变化;pH 8.3时上皮细胞出现脱离,部分出现角质化;pH 8.8时上皮细胞角质化较为严重。结果表明,水环境pH在6.8~7.8范围内比较适宜于大菱鲆幼鱼的健康生长。

  2. Modelo matemático para estimativa da temperatura média diária do ar no Estado de Goiás Mathematical model for estimating daily average air temperature in Goiás, Brazil

    Directory of Open Access Journals (Sweden)

    Jorge Cesar dos Anjos Antonini

    2009-04-01

    Full Text Available O objetivo deste trabalho foi desenvolver um modelo matemático de estimativa da temperatura média diária do ar no Estado de Goiás, que considera simultaneamente as variações espacial e temporal. O modelo foi desenvolvido por meio de uma combinação linear da altitude, latitude, longitude e da série trigonométrica de Fourier incompleta usando os três primeiros coeficientes harmônicos. Os parâmetros do modelo foram ajustados aos dados de 21 estações meteorológicas, por meio de regressão linear múltipla. O coeficiente de correlação resultante do ajuste do modelo foi de 0,91, e o índice de concordância de Willmott foi igual a 1. O modelo foi testado com os dados de três estações de altitudes diferentes: elevada (1.100 m, média (554 m e baixa (431 m. O desempenho foi considerado mediano para altitudes baixas e elevadas, e muito bom para altitudes médias.The objective of this work was to develop a mathematical model to predict the daily average of air temperature in Goiás, Brazil. The model was developed through a linear combination of altitude, latitude, longitude, and the incomplete trigonometric Fourier series using the first three harmonic coefficients. The parameters of the model were adjusted with data from 21 weather stations, using multiple linear regression. The resulting correlation coefficient of the model was 0.91, and the Willmott's index of agreement was close to 1. The model was tested with data from three additional weather stations at different altitudes: high (1,100 m, medium (554 m, and low (431 m. The performance of the model was reasonable for both high and low altitude stations, and very good for the medium altitude station.

  3. Traffic Monitor

    Science.gov (United States)

    1992-01-01

    Mestech's X-15 "Eye in the Sky," a traffic monitoring system, incorporates NASA imaging and robotic vision technology. A camera or "sensor box" is mounted in a housing. The sensor detects vehicles approaching an intersection and sends the information to a computer, which controls the traffic light according to the traffic rate. Jet Propulsion Laboratory technical support packages aided in the company's development of the system. The X-15's "smart highway" can also be used to count vehicles on a highway and compute the number in each lane and their speeds, important information for freeway control engineers. Additional applications are in airport and railroad operations. The system is intended to replace loop-type traffic detectors.

  4. Average Bandwidth Allocation Model of WFQ

    Directory of Open Access Journals (Sweden)

    Tomáš Balogh

    2012-01-01

    Full Text Available We present a new iterative method for the calculation of average bandwidth assignment to traffic flows using a WFQ scheduler in IP based NGN networks. The bandwidth assignment calculation is based on the link speed, assigned weights, arrival rate, and average packet length or input rate of the traffic flows. We prove the model outcome with examples and simulation results using NS2 simulator.

  5. Road traffic injuries in Mozambique.

    Science.gov (United States)

    Romão, Francelina; Nizamo, Hanifa; Mapasse, Domingos; Rafico, Momede Mussá; José, João; Mataruca, Simão; Efron, M Lúcia; Omondi, Lucas O; Leifert, Thelma; Bicho, Joaquim M L Marungo

    2003-01-01

    Road traffic injuries affect the economy, health and quality of life of the people of Mozambique. Current road safety programmes are inadequate and inefficient given the magnitude of the problem. Data reported on road traffic crashes in the period 1990 to 2000 from the National Institute for Road Safety, the traffic police and the Central Hospital of Maputo were reviewed. The burden of road traffic injuries in Mozambique is rising, with at least three people killed daily. The age group most affected is 25-38 (39.35%), followed by 16-24 (20.79%). The main causes of crashes include reckless driving, drunken driving, roads with potholes, inadequate signs, lack of protection for pedestrians, and inadequate traffic law enforcement. However, the data are not adequate to reveal the true magnitude of the problem. Data collected by different sources are incomplete and not coordinated with other sources and databases. In urban areas, however, better response to crashes, treatment of the injured, reporting and data collection is attributable to a greater concentration of police and medical facilities. Road traffic safety programmes in Mozambique are inadequate and inefficient, starting with the data collection system. Improvement of injury surveillance systems is needed to help make road traffic safety a national development agenda priority and for developing and implementing road safety policies. For road safety programmes to be effective, government must facilitate stakeholders' involvement, and the clear definition of government activities, civil society activities and public-private partnerships need to be established.

  6. Traffic management and control in intelligent vehicle highway systems

    NARCIS (Netherlands)

    Baskar, L.D.

    2009-01-01

    Traffic congestion is a problem experienced daily by most of us. Among various traffic management schemes, efficient utilisation of the existing roadside infrastructure combined with in-vehicle technologies offers a promising solution to address traffic congestion and related problems. This approach

  7. The Stability of Multi-modal Traffic Network

    Institute of Scientific and Technical Information of China (English)

    HAN Ling-Hui; Sun Hui-Jun; ZHU Cheng-Juan; WU Jian-Jun; JIA Bin

    2013-01-01

    There is an explicit and implicit assumption in multimodal traffic equilibrium models,that is,if the equilibrium exists,then it will also occur.The assumption is very idealized; in fact,it may be shown that the quite contrary could happen,because in multimodal traffic network,especially in mixed traffic conditions the interaction among traffic modes is asymmetric and the asymmetric interaction may result in the instability of traffic system.In this paper,to study the stability of multimodal traffic system,we respectively present the travel cost function in mixed traffic conditions and in traffic network with dedicated bus lanes.Based on a day-to-day dynamical model,we study the evolution of daily route choice of travelers in multimodal traffic network using 10000 random initial values for different cases.From the results of simulation,it can be concluded that the asymmetric interaction between the cars and buses in mixed traffic conditions can lead the traffic system to instability when traffic demand is larger.We also study the effect of travelers' perception error on the stability of multimodal traffic network.Although the larger perception error can alleviate the effect of interaction between cars and buses and improve the stability of traffic system in mixed traffic conditions,the traffic system also become instable when the traffic demand is larger than a number.For all cases simulated in this study,with the same parameters,traffic system with dedicated bus lane has better stability for traffic demand than that in mixed traffic conditions.We also find that the network with dedicated bus lane has higher portion of travelers by bus than it of mixed traffic network.So it can be concluded that building dedicated bus lane can improve the stability of traffic system and attract more travelers to choose bus reducing the traffic congestion.

  8. Traffic Light Detection at Night

    DEFF Research Database (Denmark)

    Jensen, Morten Bornø; Philipsen, Mark Philip; Bahnsen, Chris

    2015-01-01

    Traffic light recognition (TLR) is an integral part of any in- telligent vehicle, it must function both at day and at night. However, the majority of TLR research is focused on day-time scenarios. In this paper we will focus on detection of traffic lights at night and evalu- ate the performance...... of three detectors based on heuristic models and one learning-based detector. Evaluation is done on night-time data from the public LISA Traffic Light Dataset. The learning-based detector out- performs the model-based detectors in both precision and recall. The learning-based detector achieves an average...

  9. Estimating emissions from railway traffic

    Energy Technology Data Exchange (ETDEWEB)

    Joergensen, M.W.; Sorenson, C.

    1997-07-01

    The report discusses methods that can be used to estimate the emissions from various kinds of railway traffic. The methods are based on the estimation of the energy consumption of the train, so that comparisons can be made between electric and diesel driven trains. Typical values are given for the necessary traffic parameters, emission factors, and train loading. Detailed models for train energy consumption are presented, as well as empirically based methods using average train speed and distance between stop. (au)

  10. First-passage probability of the deflection of a cable-stayed bridge under long-term site-specific traffic loading

    Directory of Open Access Journals (Sweden)

    Naiwei Lu

    2017-01-01

    Full Text Available Long-span bridges suffer from higher traffic loads and the simultaneous presence of multiple vehicles, which in conjunction with the steady traffic growth may pose a threat to the bridge safety. This study presents a methodology for first-passage probability evaluation of long-span bridges subject to stochastic heavy traffic loading. Initially, the stochastic heavy traffic loading was simulated based on long-term weigh-in-motion measurements of a highway bridge in China. A computational framework was presented integrating Rice’s level-crossing theory and the first-passage criterion. The effectiveness of the computational framework was demonstrated through a case study of a cable-stayed bridge. Numerical results show that the upper tail fitting of the up-crossing rate is an appropriate description of probability characteristics of the extreme traffic load effects of long-span bridges. The average daily truck traffic growth increases the probability of exceedance due to an intensive heavy traffic flow and results in a higher first-passage probability, but this increased trend is weakening as the continuous increase of the traffic volume. Since the sustained growth of gross vehicle weight has a constant impact on the probability of failure, setting a reasonable threshold overload ratio is an effective scheme as a traffic management to ensure the bridge serviceability.

  11. Measures for Reducing Traffic Congestion in Cities

    Directory of Open Access Journals (Sweden)

    Ivan Dadić

    2012-10-01

    Full Text Available Traffic planners and designers are daily confronted by theproblems of traffic flow. Finding a solution for the optimal organisationof the traffic system in the wider (at the state leveland the narrower sense (cities, towns, requires accurate planningand adequate financing. With Croatia being a developingcountry that has higher investments into the traffic system, thematerial means need to be rati01~t~lised and the human andland resources cautiously managed. With the development andimplementation of the traffic studies, an improvement of thetraffic in cities can be expected. The work describes the trafficmeasures which provide higher quality traffic flow, with low investments.They can be used as guidelines in planning the trafficand as the first implementations of solutions from the trafficstudies.

  12. Development of River Traffic in the Traffic System of Central Croatia

    Directory of Open Access Journals (Sweden)

    Dragan Badanjak

    2006-05-01

    Full Text Available From the aspect of public transport of passengers andgoods, the traffic system in Central Croatia consists of road,rail, air and river subsystems. Regarding their share in the volumeof passenger and cargo transport as well as the carried outtransport operations in the traffic system of Central Croatia,road and rail traffic are the dominant traffic subsystems. Regardingits technical, technological, organizational and economicindicators, the river traffic system represents the less developedsubsystem of the traffic system of Central Croatia, andthe situation in this respect is not much different at the nationallevel either.The possibilities for the development of river traffic systemhave not been sufficiently used, although the potential trafficdemand for the transportation services are substantial, especiallywhen considering the river Sava which potentially offersa direct connection to the trunk European waterway. The advantagesof the Central Croatian location undoubtedly lie inthe traffic and geo-strategic position, but the value of this locationcan be used only then when the quality level of the trafficsystem and the construction level of the infrastructurecatch up with the ones in the developed European countries.The conditions for the traffic development are first of allstrong and daily faster changes in the strata, especially regardingthe implementation of new solutions and increasing theefficiency of the overall traffic system. It is precisely for thisreason that special interest should be to study the traffic valuesaccording to the available data, establish their possiblerules as function of time, and design appropriate mathematicalmodels with the aim of forecasting the traffic developmentin the future.

  13. On the reproducibility of spatiotemporal traffic dynamics with microscopic traffic models

    CERN Document Server

    Knorr, Florian

    2012-01-01

    Traffic flow is a very prominent example of a driven non-equilibrium system. A characteristic phenomenon of traffic dynamics is the spontaneous and abrupt drop of the average velocity on a stretch of road leading to congestion. Such a traffic breakdown corresponds to a boundary-induced phase transition from free flow to congested traffic. In this paper, we study the ability of selected microscopic traffic models to reproduce a traffic breakdown, and we investigate its spatiotemporal dynamics. For our analysis, we use empirical traffic data from stationary loop detectors on a German Autobahn showing a spontaneous breakdown. We then present several methods to assess the results and compare the models with each other. In addition, we will also discuss some important modeling aspects and their impact on the resulting spatiotemporal pattern. The investigation of different downstream boundary conditions, for example, shows that the physical origin of the traffic breakdown may be artificially induced by the setup of...

  14. On the reproducibility of spatiotemporal traffic dynamics with microscopic traffic models

    Science.gov (United States)

    Knorr, Florian; Schreckenberg, Michael

    2012-10-01

    Traffic flow is a very prominent example of a driven non-equilibrium system. A characteristic phenomenon of traffic dynamics is the spontaneous and abrupt drop of the average velocity on a stretch of road leading to congestion. Such a traffic breakdown corresponds to a boundary-induced phase transition from free flow to congested traffic. In this paper, we study the ability of selected microscopic traffic models to reproduce a traffic breakdown, and we investigate its spatiotemporal dynamics. For our analysis, we use empirical traffic data from stationary loop detectors on a German Autobahn showing a spontaneous breakdown. We then present several methods to assess the results and compare the models with each other. In addition, we will also discuss some important modeling aspects and their impact on the resulting spatiotemporal pattern. The investigation of different downstream boundary conditions, for example, shows that the physical origin of the traffic breakdown may be artificially induced by the setup of the boundaries.

  15. Urban traffic congestion propagation and bottleneck identification

    Institute of Scientific and Technical Information of China (English)

    LONG JianCheng; GAO ZiYou; REN HuaLing; LIAN AiPing

    2008-01-01

    Bottlenecks in urban traffic network are sticking points in restricting network col-lectivity traffic efficiency.To identify network bottlenecks effectively is a founda-tional work for improving network traffic condition and preventing traffic conges-tion.In this paper,a congestion propagation model of urban network traffic is proposed based on the cell transmission model (CTM).The proposed model in-cludes a link model,which describes flow propagation on links,and a node model,which represents link-to-link flow propagation.A new method of estimating average journey velocity (AJV) of both link and network is developed to identify network congestion bottlenecks.A numerical example is studied in Sioux Falls urban traffic network.The proposed model is employed in simulating network traffic propaga-tion and congestion bottleneck identification under different traffic demands.The simulation results show that continual increase of traffic demand is an immediate factor in network congestion bottleneck emergence and increase as well as re-ducing network collectivity capability.Whether a particular link will become a bot-tleneck is mainly determined by its position in network,its traffic flow (attributed to different OD pairs) component,and network traffic demand.

  16. Daily Democracy

    DEFF Research Database (Denmark)

    Larson, Karin; Giro, Francesca; Graham, Todd

    , it ignores the communicative mundaneness of daily democracy. This paper accordingly in- vestigates and compares the ways in which members of parliament (MPs) in three European countries – Italy, Sweden and United Kingdom – utilize Twit- ter during off-peak periods, focusing on the extent to which social...... media are fostering a more ‘connected’ and reciprocal relationship between citizens and politicians. Throughout many Western democracies, research points to the in- creasing valorisation of Twitter as an informal, intimate and open space for (ev- eryday) political communication, raising important...

  17. 季节性差分自回归滑动平均模型在上海市道路交通伤害预测中的应用%Application of Seasonal Autoregressive Integrated Moving Average Model to Road Traffic Injury Prediction in Shanghai

    Institute of Scientific and Technical Information of China (English)

    喻彦; 侯心一; 苏慧佳; 任宏

    2012-01-01

    [ Objective ] To explore the feasibility of seasonal autoregressive integrated moving average (SARIMA) model in predicting road traffic injury, and to provide reference for road traffic injury trends in Shanghai. [ Methods ] A SARIMA model was presented to fit the seasonal road traffic mortality data of Shanghai (2000-2009) via EVIEWS software, and estimated mortalities of 2010 were verified with the actual data. [ Results ] The seasonal component was statistically significant in Shanghai's road traffic mortality data. A decreasing trend was observed in the trend component of the model. SARIMA (2, 1, 0) (0, 1, 1)4 was the best fitting model among various candidate models. The predicted seasonal mortalities of 2010 were 1.49/105, 1.74/105, 1.93/105, and 2.06/105 respectively. The actual values were all in the prediction intervals, and the residuals were considered as white noise serial. The verification with actual data passed our test. [ Conclusion ] A SARIMA model can be used in accurate trends prediction of road traffic injury and therefore can provide evidences for road traffic injury intervention.%[目的]探讨季节性差分自回归滑动平均( SARIMA)模型预测道路交通伤害的可行性,为掌握上海市交通伤害趋势提供依据.[方法]利用EVIEWS软件对2000-2009年上海市道路交通伤害死亡的季度数据进行SARIMA模型拟合,并利用2010年数据对预测数据进行验证.[结果]上海市道路交通死亡具有明显的季节要素,趋势要素呈逐步下降趋势;对原始图形识别后,综合考察几种模型拟合优劣,最终采用SARIMA(2,1,0)(0,1,1)4,其能很好地拟合上海市道路交通伤害死亡情况.2010年4个季度死亡率预测值分别为1.49/105、1.74/105、1.93/105和2.06/105,实际值均在预测区间内,残差也显示为白噪声序列.预测结果较好.[结论]SARIMA模型是一种能较好地预测道路交通伤害趋势的工具,可为预防与控制道路交通伤害提供决策依据.

  18. Estimation Models for Average Speed of Traffic Flow Based on GPS Data of Taxi%基于出租车GPS数据的路段平均速度估计模型

    Institute of Scientific and Technical Information of China (English)

    姜桂艳; 常安德; 李琦; 伊峰

    2011-01-01

    The existing average speed estimation models based on GPS ( global positioning system) data of taxis are not applicable where high precision and low cost are of necessities. Two traditional models, namely a time integral model and a time interpolation model, based on the GPS data of taxis were modified, and the two modified models were combined to form a hybrid model. The three new models were verified using GPS data of taxis obtained from a part of road network of a large city. The results shown that the estimating precisions of the two modified models increased by 1. 5% and 19.7% , respectively, compared with the original time integral model and time interpolation model, and those of the hybrid model by 2. 8% and 8. 8% , respectively, compared with the two modified models.%为了解决现有基于GPS数据的路段平均速度估计模型应用条件苛刻、难以满足低成本和高精度信息需求问题,考虑不同类型GPS车辆运行特征,设计了两个基于出租车GPS数据估计路段平均速度的改进模型.基于两个改进模型,设计了路段平均速度的融合估计方法.用某城市局部路网的出租车GPS数据验证两个改进模型,并与传统模型进行了对比分析.结果表明,在不增加成本的条件下,两个改进模型的估计精度分别比传统模型提高了1.5%与19.7%;融合估计方法的精度比两个改进模型分别提高了2.8%与8.8%.

  19. SORCE Level 3 Total Solar Irradiance Daily Average V016

    Data.gov (United States)

    National Aeronautics and Space Administration — The Total Solar Irradiance (TSI) data set SOR3TSID contains the total solar irradiance (a.k.a solar constant) data collected by the Total Irradiance Monitor (TIM)...

  20. Global solar irradiation in Italy during 1994 : monthly average daily values for 1614 sites estimated from Meteosat images; Radiazione solare globale al suolo in Italia nel 1994 : valori medi mensili per 1.614 localita` italiane stimate a partire dalle immagini fornite dal satellite Meteosat

    Energy Technology Data Exchange (ETDEWEB)

    Cogliani, E.; Mancini, M.; Petrarca, S.; Spinelli, F. [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dip. Energia

    1995-10-01

    The global solar radiation over Italy is estimated from Meteosat secondary images in the visible band. The stimation method relies on the fact that the cloud cover on a given area of the Earth`s surface statistically determines the amount of solar radiation falling on that area. Estimated values of the monthly average daily global radiation on a horizontal surface for the 1994 have been compared with values computed from data measured by the stations of the two Italian radiation networks: the Meteorological Service of the Italian Air Force and the National Agrometeorological Network (a total of 36 stations have been considered). The mean percentage difference between estimated and computed values over the year is 6 per cent. In the present report, the monthly maps of radiation over Italy and the estimated monthly average daily values for over 1600 sites (having more than 10,000 inhabitants) are given. In the yearly reports to be issued in the years to come, maps and mean values over the period starting with 1994 will be given as well.

  1. A statistical approach to vehicular traffic

    CERN Document Server

    Freund, J A; Freund, Jan; Poschel, Thorsten

    1995-01-01

    A two--dimensional cellular automaton is introduced to model the flow and jamming of vehicular traffic in cities. Each site of the automaton represents a crossing where a finite number of cars can wait approaching the crossing from each of the four directions. The flow of cars obeys realistic traffic rules. We investigate the dependence of the average velocity of cars on the global traffic density. At a critical threshold for the density the average velocity reduces drastically caused by jamming. For the low density regime we provide analytical results which agree with the numerical results.

  2. Estimating cost of road traffic injuries in Iran using willingness to pay (WTP method.

    Directory of Open Access Journals (Sweden)

    Elaheh Ainy

    Full Text Available We aimed to use the willingness to pay (WTP method to calculate the cost of traffic injuries in Iran in 2013. We conducted a cross-sectional questionnaire-based study of 846 randomly selected road users. WTP data was collected for four scenarios for vehicle occupants, pedestrians, vehicle drivers, and motorcyclists. Final analysis was carried out using Weibull and maximum likelihood method. Mean WTP was 2,612,050 Iranian rials (IRR. Statistical value of life was estimated according to 20,408 fatalities 402,314,106,073,648 IRR (US$13,410,470,202 based on purchasing power parity at (February 27th, 2014. Injury cost was US$25,637,870,872 (based on 318,802 injured people in 2013, multiple daily traffic volume of 311, and multiple daily payment of 31,030 IRR for 250 working days. The total estimated cost of injury and death cases was 39,048,341,074$. Gross national income of Iran was, US$604,300,000,000 in 2013 and the costs of traffic injuries constituted 6·46% of gross national income. WTP was significantly associated with age, gender, monthly income, daily payment, more payment for time reduction, trip mileage, drivers and occupants from road users. The costs of traffic injuries in Iran in 2013 accounted for 6.64% of gross national income, much higher than the global average. Policymaking and resource allocation to reduce traffic-related death and injury rates have the potential to deliver a huge economic benefit.

  3. Urban scale air quality modelling using detailed traffic emissions estimates

    Science.gov (United States)

    Borrego, C.; Amorim, J. H.; Tchepel, O.; Dias, D.; Rafael, S.; Sá, E.; Pimentel, C.; Fontes, T.; Fernandes, P.; Pereira, S. R.; Bandeira, J. M.; Coelho, M. C.

    2016-04-01

    The atmospheric dispersion of NOx and PM10 was simulated with a second generation Gaussian model over a medium-size south-European city. Microscopic traffic models calibrated with GPS data were used to derive typical driving cycles for each road link, while instantaneous emissions were estimated applying a combined Vehicle Specific Power/Co-operative Programme for Monitoring and Evaluation of the Long-range Transmission of Air Pollutants in Europe (VSP/EMEP) methodology. Site-specific background concentrations were estimated using time series analysis and a low-pass filter applied to local observations. Air quality modelling results are compared against measurements at two locations for a 1 week period. 78% of the results are within a factor of two of the observations for 1-h average concentrations, increasing to 94% for daily averages. Correlation significantly improves when background is added, with an average of 0.89 for the 24 h record. The results highlight the potential of detailed traffic and instantaneous exhaust emissions estimates, together with filtered urban background, to provide accurate input data to Gaussian models applied at the urban scale.

  4. Jamitons: Phantom Traffic Jams

    Science.gov (United States)

    Kowszun, Jorj

    2013-01-01

    Traffic on motorways can slow down for no apparent reason. Sudden changes in speed by one or two drivers can create a chain reaction that causes a traffic jam for the vehicles that are following. This kind of phantom traffic jam is called a "jamiton" and the article discusses some of the ways in which traffic engineers produce…

  5. Physics of Traffic and the Crowds Theory: AMultidisciplinary Approach to Mobility Education

    Institute of Scientific and Technical Information of China (English)

    Laura Tamburini[1,2; Sabrina Colomban[3

    2015-01-01

    Crowding is a reality in which we find ourselves involved daily. The crowd produced in a traffic jam is a dynamic entity inwhich the application of physics, mathematics and biology can provide practical help to understand how and why this problematicsituation occurs and what solutions can be found to resolve it. In the mobility education project "SicuraMENTE", we carried out anexperiment on the conduct of a crowd by simulating a situation of intense city traffic. Taking a cue from an experimental situationproposed in traffic physics, we have verified that a route with limited access can generate a traffic jam and the crowd of pedestrianscan be mitigated by forcing the crowd to use dedicated streets. Taking the outgoing time of the student crowd from the outlet road,with and without the presence of an obstacle in the middle of the roadway, it was found that the traffic jam is resolved more quicklyin the situation with an obstacle because the flow of people is divided into two separate channels, reducing the probability that twoindividuals are close and that this creates an obstruction (example of counter-intuitive physical principle). We also verified that thespeed of the elements of the crowd influences the formation of traffic jams, which are on average more likely in the case of higherspeed. These important aspects in the design of road networks and transport infrastructure have made students reason on physics'topics, but also on the correct conduct in traffic. The multidisciplinary approach in education for safe and sustainable mobility, soinnovative in Italy, turned out to be effective in terms of teaching in the frame of a mix of academic disciplines, in which road safetyeducation has become the context and the goal.

  6. TRANSIMS traffic flow characteristics

    CERN Document Server

    Nagel, K; Pieck, M; Donnelly, R; Barrett, C L; Nagel, Kai; Stretz, Paula; Pieck, Martin; Donnelly, Rick; Barrett, Christopher L.

    1997-01-01

    Knowledge of fundamental traffic flow characteristics of traffic simulation models is an essential requirement when using these models for the planning, design, and operation of transportation systems. In this paper we discuss the following: a description of how features relevant to traffic flow are currently under implementation in the TRANSIMS microsimulation, a proposition for standardized traffic flow tests for traffic simulation models, and the results of these tests for two different versions of the TRANSIMS microsimulation.

  7. Vehicle-class Specific Control of Freeway Traffic

    NARCIS (Netherlands)

    Schreiter, T.

    2013-01-01

    The increase of mobility of the past decades has led to substantial congestion on the freeways. Traffic jams emerge both on a daily basis at the same location, as well as during accidents when a part of the freeways is temporarily blocked. In those cases, traffic management centers intervene into tr

  8. Análisis metodológico de la distribución espacial de la precipitación y la estimación media diaria Methodological analysis of the spatial distribution of rainfall and the average daily stimation

    Directory of Open Access Journals (Sweden)

    Mauro Íñiguez Covarrubias

    2011-02-01

    Full Text Available El objetivo del trabajo consistió en mostrar un análisis metodológico geoestadístico, para generar un patrón espacial de la lluvia, asociado a la precipitación media diaria. Caracterizar y conocer la distribución espacial de la precipitación, también conocida como "campo de tormenta" y asociarla a un modelo de distribución o sustituirla por una precipitación media por métodos convencionales, es un reto importante en estudios de las ciencias del agua. La metodología propuesta requiere de la construcción de un variograma, elaborado por un ajuste de datos experimentales de un campo de tormenta, que sirva como base para generar la distribución espacial de la lluvia con la aplicación del método geoestadístico del "krigeado". Esto permite determinar la precipitación media diaria de una cuenca hidrográfica. Los resultados muestran que es posible obtener una función que relacione la lluvia media con el campo de tormenta, mediante los parámetros α y β del variograma ajustado a un modelo esférico. Para validar la aplicación de la metodología se analizaron varios eventos, aquí se presentan dos eventos de precipitación observada en la cuenca del río Juchipila, y río Calvillo, entre los estados de Aguascalientes y Zacatecas. Los resultados muestran una relación única de la lluvia media diaria con la distribución espacial, representada por el campo de tormenta. Asimismo, se encontró que el valor óptimo de la función es mínimo al compararlo con los resultados obtenidos por cuatro métodos convencionales: promedio aritmético, polígonos de Thiessen, método de isoyetas y método de krigeado lineal.The aim of the study was to show a geostatistical methodological analysis to create a spatial pattern of rain, related to average daily rainfall. Defining and knowing the spatial distribution of rainfall, also known as the "storm field" and related to a distribution model, or replacing it to an average rainfall using conventional

  9. Role of highway traffic on spatial and temporal distributions of air pollutants in a Swiss Alpine valley.

    Science.gov (United States)

    Ducret-Stich, Regina E; Tsai, Ming-Yi; Ragettli, Martina S; Ineichen, Alex; Kuenzli, Nino; Phuleria, Harish C

    2013-07-01

    Traffic-related air pollutants show high spatial variability near roads, posing a challenge to adequately assess exposures. Recent modeling approaches (e.g. dispersion models, land-use regression (LUR) models) have addressed this but mostly in urban areas where traffic is abundant. In contrast, our study area was located in a rural Swiss Alpine valley crossed by the main North-south transit highway of Switzerland. We conducted an extensive measurement campaign collecting continuous nitrogen dioxide (NO₂), particulate number concentrations (PN), daily respirable particulate matter (PM10), elemental carbon (EC) and organic carbon (OC) at one background, one highway and seven mobile stations from November 2007 to June 2009. Using these measurements, we built a hybrid model to predict daily outdoor NO₂ concentrations at residences of children participating in an asthma panel study. With the exception of OC, daily variations of the pollutants followed the temporal trends of heavy-duty traffic counts on the highway. In contrast, variations of weekly/seasonal means were strongly determined by meteorological conditions, e.g., winter inversion episodes. For pollutants related to primary exhaust emissions (i.e. NO₂, EC and PN) local spatial variation strongly depended on proximity to the highway. Pollutant concentrations decayed to background levels within 150 to 200 m from the highway. Two separate daily NO₂ prediction models were built using LUR approaches with (a) short-term traffic and weather data (model 1) and (b) subsequent addition of daily background NO₂ to previous model (model 2). Models 1 and 2 explained 70% and 91% of the variability in outdoor NO₂ concentrations, respectively. The biweekly averaged predictions from the final model 2 agreed very well with the independent biweekly integrated passive measurements taken at thirteen homes and nine community sites (validation R(2)=0.74). The excellent spatio-temporal performance of our model provides a

  10. Virtual speed sensors based algorithm for expressway traffic state estimation

    Institute of Scientific and Technical Information of China (English)

    XU DongWei; DONG HongHui; JIA LiMin; QIN Yong

    2012-01-01

    The accurate estimation of expressway traffic state can provide decision-making for both travelers and traffic managers.The speed is one of the most representative parameter of the traffic state.So the expressway speed spatial distribution can be taken as the expressway traffic state equivalent.In this paper,an algorithm based on virtual speed sensors (VSS) is presented to estimate the expressway traffic state (the speed spatial distribution).To gain the spatial distribution of expressway traffic state,virtual speed sensors are defined between adjacent traffic flow sensors.Then,the speed data extracted from traffic flow sensors in time series are mapped to space series to design virtual speed sensors.Then the speed of virtual speed sensors can be calculated with the weight matrix which is related with the speed of virtual speed sensors and the speed data extracted from traffic flow sensors and the speed data extracted from traffic flow sensors in time series.Finally,the expressway traffic state (the speed spatial distribution) can be gained.The acquisition of average travel speed of the expressway is taken for application of this traffic state estimation algorithm.One typical expressway in Beijing is adopted for the experiment analysis.The results prove that this traffic state estimation approach based on VSS is feasible and can achieve a high accuracy.

  11. Legal aspects of motor traffic trauma in Sri Lanka

    OpenAIRE

    Clifford Perera

    2016-01-01

    Motor traffic trauma has become a significant denominator of morbidity and mortality statistics in modern Sri Lanka. In 2010, 26,847 were seriously injured, and 2721 people died as a result of road traffic trauma. In 2014, nearly 38,500 road traffic accidents were reported of which 36% were categorized as “critical” with nearly 7% fatalities. Road traffic crashes have increased by 249% between 1977 and 2004. On average, road traffic trauma kills one person in Sri Lanka every 4.5 h. In the 30 ...

  12. Efeito do creep feeding sobre o desempenho de bezerros e a eficiência reprodutiva de primíparas Nelore, em pastejo Effect of creep feeding on average daily gain and weaning weight of calves and on reproductive efficiency of primiparous Nelore cows under grazing

    Directory of Open Access Journals (Sweden)

    E. Nogueira

    2006-08-01

    Full Text Available Avaliou-se o efeito da suplementação de bezerros em sistema de creep feeding, em pastagens de Brachiaria brizantha, durante o período de amamentação, sobre o ganho médio diário (GMD, peso à desmama (PD e taxa de gestação, em delineamento inteiramente ao acaso, utilizando 102 vacas Nelore (primíparas de baixa condição corporal ao início da estação de monta e seus bezerros, divididos em dois grupos: T1 (n=52, não tratado e T2 (n=50, tratado com suplemento à base de 20% de PB e 75% de NDT. O consumo médio diário estimado no período foi 0,61kg de suplemento/bezerro/dia. Observaram-se diferenças entre T1 e T2 quanto ao PD (P0,05. A suplementação em creep feeding pode aumentar o GMD e o PD de bezerros Nelore, sem alterar a taxa de gestação de primíparas que iniciam a estação de monta com baixa condição corporal.The effect of creep feeding on average daily gain (ADG and weaning weight (WW of calves and pregnancy rate of dams was evaluated in Nelore cattle on Brachiaria Brizantha pasture. In a complete randomized design, calves were divided into two treatments: T1, the control group and T2, in which calves were provided a supplemental diet containing 20% CP and 75% TDN from 92 days after birth until weaning. The 102 primiparous cows were in low body condition at beginning of breeding season. Average daily consumption of the creep ration was 0.61kg per calf. WW averaged 155.10±2.72kg and 163.80±2.53 and for T1 and T2 calves, respectively (P0.05. Thus, creep feeding can improve WW and preweaning ADG of Nelore calves but may not affect pregnancy rate of primiparous cows in low body condition at the start of the mating.

  13. Traffic Police in Ji’nan

    Institute of Scientific and Technical Information of China (English)

    1997-01-01

    The 13 traffic policewomen of No. 7 Ergang Road in the city of Ji’nan. Shandong Province, hold a special feminine spiritual outlook. Wearing their olive green berets, under the guidance of Captain Shi Li, they began to take point duty at the traffic stand on October 1, 1996. Graduates of the Shandong Public Security Professional College at the average age of 22, these women began formal group training in Sep

  14. Subjective safety in traffic.

    NARCIS (Netherlands)

    2012-01-01

    The term ‘subjective safety in traffic’ refers to people feeling unsafe in traffic or, more generally, to anxiety regarding being unsafe in traffic for oneself and/or others. Subjective safety in traffic can lead to road users limiting their mobility and social activities, which is one of the reason

  15. A cellular automaton model for a bridge traffic bottleneck

    Institute of Scientific and Technical Information of China (English)

    Shifa Xiao; Lingjiang Kong; Muren Liu

    2005-01-01

    A cellular automaton (CA) model is proposed in this paper to analyze a bridge traffic bottleneck. The simulation results with this model show that there are several phase transitions in the traffic average density, velocity and flow for each lane under a periodic boundary condition. An unstable phase in the traffic average density and velocity for the upstream and downstream lanes of the bridge is shown in a range of initial traffic densities. The critical points of the phase transitions and the phenomenon of the unstable phase found in the simulation are also explained with the mean-field theory.

  16. Efeito da idade da vaca e da data juliana de nascimento sobre o ganho médio diário de bezerros de corte no período pré-desmame Effects of age of the dam and julian birth date on average daily gain of beef calves from birth to wean

    Directory of Open Access Journals (Sweden)

    A.L. Bocchi

    2005-08-01

    observed for cows averaging 6 and 9 years for Tabapuã and Nelore breeds, respectively. The best daily weight gain from birth to wean was also observed in the winter for both breeds. Correction factors were calculated for breed, and those for IDV were calculated separately for males and females. The correction factors for DJN were calculated for each season. The calculated correction factors allowed higher precision in the selection of animals by reducing the non genetic effects on the variation of daily weight gain from birth to wean.

  17. Modeling cyclist acceleration process for bicycle traffic simulation using naturalistic data

    OpenAIRE

    Ma, Xiaoliang; Luo, Ding

    2016-01-01

    Cycling is a healthy and sustainable form of transportation. The recent increase of daily cyclists in Sweden has triggered broad interest in finding how policies and measures may facilitate the planning of bicycle traffic in the urban area. However, in comparison to car traffic, bicycle traffic is still far from well understood. This study is part of the research effort to investigate microscopic cyclist behavior, model bicycle traffic and finally build a simulation tool for applications in t...

  18. Robust identification for multi-section freeway traffic models

    Institute of Scientific and Technical Information of China (English)

    Zhongke SHI

    2005-01-01

    Since it is difficult to fit measured parameters using the conventional traffic model, a new traffic density and average speed model is introduced in this paper.To determine traffic model structures accurately, a model identification method for uncertain nonlinear system is developed.To simplify uncertain nonlinear problem, this paper presents a new robust criterion to identify the multi-section traffic model structure of freeway efficiently.In the new model identification criterion,numerically efficient U-D factorization is used to avoid computing the determinant values of two complex matrices.By estimating the values of U-D factor of data matrix, both the upper and lower bounds of system uncertainties are described. Thus a model structure identification algorithm is proposed.Comparisons between identification outputs and simulation outputs of traffic states show that the traffic states can be accurately predicted by means of the new traffic models and the structure identification criterion.

  19. A Marine Traffic Flow Model

    Directory of Open Access Journals (Sweden)

    Tsz Leung Yip

    2013-03-01

    Full Text Available A model is developed for studying marine traffic flow through classical traffic flow theories, which can provide us with a better understanding of the phenomenon of traffic flow of ships. On one hand, marine traffic has its special features and is fundamentally different from highway, air and pedestrian traffic. The existing traffic models cannot be simply extended to marine traffic without addressing marine traffic features. On the other hand, existing literature on marine traffic focuses on one ship or two ships but does not address the issues in marine traffic flow.

  20. Forced versus free traffic in an automated milking system

    DEFF Research Database (Denmark)

    Munksgaard, Lene; Rushen, J.; de Passillé, A.M.;

    2011-01-01

    Cows in automated milking systems with free access to feeders sometimes show a reduced use of the robotic milkers, while forced traffic where cows have to pass through the robot to reach the feeders may reduce feeding time and frequency. We examined two groups of 35 lactating cows. For 21 d, one....... The average number of visits to the robot, either with or without milking, did not differ between the two types of traffic. On average cows lay down for 12.3 h/d, with no significant difference between free and forced traffic. The type of traffic did not affect the duration of time spent in the feeding area....... With both forced and free traffic, there was marked diurnal variation in feeding, with relatively little feeding occurring between 2200 h and 0800 h. Use of forced traffic did not reduce feeding time. It did not improve access to the robot milker or eliminate diurnal variation. Differences between cows...

  1. Implications of traffic characteristics on interdomain traffic engineering

    OpenAIRE

    Uhlig, Steve

    2004-01-01

    This thesis discusses the implications of the traffic characteristics on interdomain traffic engineering with BGP. We first provide an overview of the interdomain traffic control problem. Then, we present results concerning the characteristics of the interdomain traffic, based on the analysis of real traffic traces gathered from non-transit ASes. We discuss the implications of the topological properties of the traffic on interdomain traffic engineering. Based on this knowledge of the...

  2. Impact analysis of traffic-related air pollution based on real-time traffic and basic meteorological information.

    Science.gov (United States)

    Pan, Long; Yao, Enjian; Yang, Yang

    2016-12-01

    With the rapid development of urbanization and motorization in China, traffic-related air pollution has become a major component of air pollution which constantly jeopardizes public health. This study proposes an integrated framework for estimating the concentration of traffic-related air pollution with real-time traffic and basic meteorological information and also for further evaluating the impact of traffic-related air pollution. First, based on the vehicle emission factor models sensitive to traffic status, traffic emissions are calculated according to the real-time link-based average traffic speed, traffic volume, and vehicular fleet composition. Then, based on differences in meteorological conditions, traffic pollution sources are divided into line sources and point sources, and the corresponding methods to determine the dynamic affecting areas are also proposed. Subsequently, with basic meteorological data, Gaussian dispersion model and puff integration model are applied respectively to estimate the concentration of traffic-related air pollution. Finally, the proposed estimating framework is applied to calculate the distribution of CO concentration in the main area of Beijing, and the population exposure is also calculated to evaluate the impact of traffic-related air pollution on public health. Results show that there is a certain correlation between traffic indicators (i.e., traffic speed and traffic intensity) of the affecting area and traffic-related CO concentration of the target grid, which indicates the methods to determine the affecting areas are reliable. Furthermore, the reliability of the proposed estimating framework is verified by comparing the predicted and the observed ambient CO concentration. In addition, results also show that the traffic-related CO concentration is higher in morning and evening peak hours, and has a heavier impact on public health within the Fourth Ring Road of Beijing due to higher population density and higher CO

  3. Effect of violating the traffic light rule in the Biham-Middleton-Levine traffic flow model

    Science.gov (United States)

    Ding, Zhong-Jun; Jiang, Rui; Li, Ming; Li, Qi-Lang; Wang, Bing-Hong

    2012-09-01

    This paper studies the effect of violating the traffic light rule in the Biham-Middleton-Levine (BML) traffic flow model. It is assumed that there are two kinds of drivers: normal drivers obey the traffic light rule and violators disobey it. Simulation results show that although the existence of violators increases the average velocity in the free-flowing phase, it decreases the threshold from free-flowing phase to jam. With the presence of violators, a new kind of configuration with stripe slopes -2 and -1/2 has been found in the free-flowing phase. We have developed an analytical investigation which successfully predicts the average velocity in the free-flowing phase. A phase separation phenomenon, where jams and freely flowing traffic coexist, has been found in the intermediate car density range. The mechanism of the phase separation has been illustrated.

  4. Tri-level programming model for combined urban traffic signal control and traffic flow guidance

    Institute of Scientific and Technical Information of China (English)

    孙智源; 陆化普; 屈闻聪

    2016-01-01

    In order to balance the temporal-spatial distribution of urban traffic flow, a model is established for combined urban traffic signal control and traffic flow guidance. With consideration of the wide use of fixed signal control at intersections, traffic assignment under traffic flow guidance, and dynamic characteristics of urban traffic management, a tri-level programming model is presented. To reflect the impact of intersection delay on traffic assignment, the lower level model is set as a modified user equilibrium model. The middle level model, which contains several definitional constraints for different phase modes, is built for the traffic signal control optimization. To solve the problem of tide lane management, the upper level model is built up based on nonlinear 0-1 integer programming. A heuristic iterative optimization algorithm (HIOA) is set up to solve the tri-level programming model. The lower level model is solved by method of successive averages (MSA), the middle level model is solved by non-dominated sorting genetic algorithm II (NSGA II), and the upper level model is solved by genetic algorithm (GA). A case study is raised to show the efficiency and applicability of the proposed modelling and computing method.

  5. Fluctuations in airport arrival and departure traffic: A network analysis

    Institute of Scientific and Technical Information of China (English)

    Li Shan-Mei; Xu Xiao-Hao; Meng Ling-Hang

    2012-01-01

    Air traffic is a typical complex system,in which movements of traffic components (pilots,controllers,equipment,and environment),especially airport arrival and departure traffic,form complicated spatial and temporal dynamics.The fluctuations of airport arrival and departure traffic are studied from the point of view of networks as the special correlation between different airports.Our collected flow volume data on the time-dependent activity of US airport arrival and departure traffic indicate that the coupling between the average flux and the fluctuation of an individual airport obeys a certain scaling law with a wide variety of scaling exponents between 1/2 and 1.These scaling phenomena can explain the interaction between the airport internal dynamics (e.g.queuing at airports,a ground delay program and following flying traffic) and a change in the external (network-wide) traffic demand (e.g.an increase in traffic during peak hours every day),allowing us to further understand the mechanisms governing the collective behaviour of the transportation system.We separate internal dynamics from external fluctuations using a scaling law which is helpful for us to systematically determine the origin of fluctuations in airport arrival and departure traffic,uncovering the collective dynamics.Hot spot features are observed in airport traffic data as the dynamical inhomogeneity in the fluxes of individual airports.The intrinsic characteristics of airport arrival and departure traffic under severe weather is discussed as well.

  6. Costs of traffic injuries

    DEFF Research Database (Denmark)

    Kruse, Marie

    2015-01-01

    assessed using Danish national healthcare registers. Productivity costs were computed using duration analysis (Cox regression models). In a subanalysis, cost per severe traffic injury was computed for the 12 995 individuals that experienced a severe injury. RESULTS: The socioeconomic cost of a traffic......OBJECTIVE: The aim of this study was to analyse the socioeconomic costs of traffic injuries in Denmark, notably the healthcare costs and the productivity costs related to traffic injuries, in a bottom-up, register-based perspective. METHOD: Traffic injury victims were identified using national...... emergency room data and police records. Victims were matched with five controls per case by means of propensity score, nearest-neighbour matching. In the cohort, consisting of the 52 526 individuals that experienced a traffic injury in 2000 and 262 630 matched controls, attributable healthcare costs were...

  7. Traffic Signs Inventory System

    Directory of Open Access Journals (Sweden)

    J. Ružbarský

    2013-06-01

    Full Text Available The paper is focused on practical application of Cambridge Correlator. The goal is to propose a traffic signs inventory system by using excellent characteristics of correlator in the rapid optical correlation. The proposal of this inventory system includes obtaining of traffic signs to create the database either collecting the GPS coordinates. It is necessary to know the traffic signs position and also to document the entire surface route for later evaluation in offline mode.

  8. Application of Internet in Road Traffic Engineering

    Directory of Open Access Journals (Sweden)

    Ivan Dadić

    2012-10-01

    Full Text Available The paper deals with the implementation of Internet in trafficengineering with the purpose of improving the professionaland scientific research development of the traffic system in theRepublic of Croatia.Fast growth of the world computer network, Internet, andits applications in almost all the fields of human activities,change the picture of the modern world. The current exchangeof data in all their forms and the daily growth of the network,supplemented by almost incredible amounts of data that can bealmost instantly accessible, indicates that Internet is not just theinfomwtion technology revolution, but that it is a revolutionper se. More than 100 million computers are estimated to benetworked beginning of the 21" century.Internet seems almost as if it were created for the purposesof knowledge and expe1ience exchange in traffic, a relativelyyoung scientific branch. 11 can be concluded that the presenceof traffic engineers in Internet is today's reality and tomon·ow'snecessity.

  9. A Sarsa(λ-Based Control Model for Real-Time Traffic Light Coordination

    Directory of Open Access Journals (Sweden)

    Xiaoke Zhou

    2014-01-01

    Full Text Available Traffic problems often occur due to the traffic demands by the outnumbered vehicles on road. Maximizing traffic flow and minimizing the average waiting time are the goals of intelligent traffic control. Each junction wants to get larger traffic flow. During the course, junctions form a policy of coordination as well as constraints for adjacent junctions to maximize their own interests. A good traffic signal timing policy is helpful to solve the problem. However, as there are so many factors that can affect the traffic control model, it is difficult to find the optimal solution. The disability of traffic light controllers to learn from past experiences caused them to be unable to adaptively fit dynamic changes of traffic flow. Considering dynamic characteristics of the actual traffic environment, reinforcement learning algorithm based traffic control approach can be applied to get optimal scheduling policy. The proposed Sarsa(λ-based real-time traffic control optimization model can maintain the traffic signal timing policy more effectively. The Sarsa(λ-based model gains traffic cost of the vehicle, which considers delay time, the number of waiting vehicles, and the integrated saturation from its experiences to learn and determine the optimal actions. The experiment results show an inspiring improvement in traffic control, indicating the proposed model is capable of facilitating real-time dynamic traffic control.

  10. Traffic Congestion Evaluation and Signal Control Optimization Based on Wireless Sensor Networks: Model and Algorithms

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    2012-01-01

    Full Text Available This paper presents the model and algorithms for traffic flow data monitoring and optimal traffic light control based on wireless sensor networks. Given the scenario that sensor nodes are sparsely deployed along the segments between signalized intersections, an analytical model is built using continuum traffic equation and develops the method to estimate traffic parameter with the scattered sensor data. Based on the traffic data and principle of traffic congestion formation, we introduce the congestion factor which can be used to evaluate the real-time traffic congestion status along the segment and to predict the subcritical state of traffic jams. The result is expected to support the timing phase optimization of traffic light control for the purpose of avoiding traffic congestion before its formation. We simulate the traffic monitoring based on the Mobile Century dataset and analyze the performance of traffic light control on VISSIM platform when congestion factor is introduced into the signal timing optimization model. The simulation result shows that this method can improve the spatial-temporal resolution of traffic data monitoring and evaluate traffic congestion status with high precision. It is helpful to remarkably alleviate urban traffic congestion and decrease the average traffic delays and maximum queue length.

  11. DNA adducts and PM(10) exposure in traffic-exposed workers and urban residents from the EPIC-Florence City study.

    Science.gov (United States)

    Palli, Domenico; Saieva, Calogero; Munnia, Armelle; Peluso, Marco; Grechi, Daniele; Zanna, Ines; Caini, Saverio; Decarli, Adriano; Sera, Francesco; Masala, Giovanna

    2008-09-15

    Air pollution and particulate matter in urban areas have been associated with increased mortality from cardiovascular and respiratory diseases and increased cancer risk. Carcinogenic effects of particulate matter have been related to the contents of specific compounds, such as polycyclic aromatic hydrocarbons. The latter may form bulky DNA adducts, that may be considered as candidate markers of cancer risk. We have recently shown that traffic-exposed workers and the general population in Florence have divergent levels of DNA adducts, possibly related to different levels of exposure to genotoxic agents from vehicle emissions. In the current study, in a series of 214 Florence City healthy adults enrolled in a prospective study in the period 1993-1998 (152 residents / 62 traffic-exposed workers), we investigated the correlation between individual levels of DNA bulky adducts and PM(10) exposure scores based on daily environmental measures provided by the local Environmental Protection Agency for the whole study period, by two types of urban monitoring stations (high- and low-traffic). We found that PM(10) cumulative scores from high-traffic stations over the last 1-2 weeks prior to blood drawing significantly correlated (r=0.58, p=0.02) with DNA adduct levels among non-smoking traffic-exposed workers (but not among residents with no occupational exposure to vehicle emissions). A multivariate regression analysis adjusted for possible confounders confirmed these findings. PM(10) scores from low-traffic stations did not show any correlation. These results show that DNA adduct levels in non-smoking workers reflect the average levels of exposure to PM(10) in high-traffic urban areas experienced over a time period of 1-2 weeks. Since DNA adduct levels have been found predictive of lung cancer risk, our findings provide clues relevant to the reduction of genotoxic damage and possibly cancer risk among traffic-exposed urban workers.

  12. Three-phase theory of city traffic: Moving synchronized flow patterns in under-saturated city traffic at signals

    Science.gov (United States)

    Kerner, Boris S.

    2014-03-01

    Three-phase traffic flow theory of city traffic has been developed. Based on simulations of a stochastic microscopic traffic flow model, features of moving synchronized flow patterns (MSP) have been studied, which are responsible for a random time-delayed breakdown of a green-wave (GW) organized in a city. A possibility of GW control leading to the prevention of GW breakdown has been demonstrated. A diagram of traffic breakdown in under-saturated traffic (transition from under- to over-saturated city traffic) at the signal has been found; the diagram presents regions of the average arrival flow rate, within which traffic breakdown can occur, in dependence of parameters of the time-function of the arrival flow rate or/and signal parameters. Physical reasons for a crucial difference between results of classical theory of city traffic and three-phase theory are explained. In particular, we have found that under-saturated traffic at the signal can exist during a long time interval, when the average arrival flow rate is larger than the capacity of the classical theory; the classical capacity is equal to a minimum capacity in three-phase theory. Within a range of the average arrival flow rate between the minimum and maximum signal capacities, under-saturated traffic is in a metastable state with respect to traffic breakdown. We have distinguished the following possible causes for the metastability of under-saturated traffic: (i) The arrival flow rate during the green phase is larger than the saturation flow rate. (ii) The length of the upstream front of a queue at the signal is a finite value. (iii) The outflow rate from a MSP (the rate of MSP discharge) is larger than the saturation flow rate.

  13. Traffic danger detection by visual attention model of sparse sampling

    Institute of Scientific and Technical Information of China (English)

    夏利民; 刘涛; 谭论正

    2015-01-01

    A method to detect traffic dangers based on visual attention model of sparse sampling was proposed. The hemispherical sparse sampling model was used to decrease the amount of calculation which increases the detection speed. Bayesian probability model and Gaussian kernel function were applied to calculate the saliency of traffic videos. The method of multiscale saliency was used and the final saliency was the average of all scales, which increased the detection rates extraordinarily. The detection results of several typical traffic dangers show that the proposed method has higher detection rates and speed, which meets the requirement of real-time detection of traffic dangers.

  14. Traffic Management as a Service: The Traffic Flow Pattern Classification Problem

    Directory of Open Access Journals (Sweden)

    Carlos T. Calafate

    2015-01-01

    Full Text Available Intelligent Transportation System (ITS technologies can be implemented to reduce both fuel consumption and the associated emission of greenhouse gases. However, such systems require intelligent and effective route planning solutions to reduce travel time and promote stable traveling speeds. To achieve such goal these systems should account for both estimated and real-time traffic congestion states, but obtaining reliable traffic congestion estimations for all the streets/avenues in a city for the different times of the day, for every day in a year, is a complex task. Modeling such a tremendous amount of data can be time-consuming and, additionally, centralized computation of optimal routes based on such time-dependencies has very high data processing requirements. In this paper we approach this problem through a heuristic to considerably reduce the modeling effort while maintaining the benefits of time-dependent traffic congestion modeling. In particular, we propose grouping streets by taking into account real traces describing the daily traffic pattern. The effectiveness of this heuristic is assessed for the city of Valencia, Spain, and the results obtained show that it is possible to reduce the required number of daily traffic flow patterns by a factor of 4210 while maintaining the essence of time-dependent modeling requirements.

  15. Bits of Internet traffic control

    OpenAIRE

    Vojnovic, Milan; Le Boudec, Jean Yves

    2005-01-01

    In this work, we consider four problems in the context of Internet traffic control. The first problem is to understand when and why a sender that implements an equation-based rate control would be TCP-friendly, or not—a sender is said to be TCP-friendly if, under the same operating conditions, its long-term average send rate does not exceed that of a TCP sender. It is an established axiom that some senders in the Internet would need to be TCP-friendly. An equation-based rate control sender pl...

  16. Bits of Internet Traffic Control

    OpenAIRE

    Vojnovic, Milan

    2003-01-01

    In this work, we consider four problems in the context of Internet traffic control. The first problem is to understand when and why a sender that implements an equation-based rate control would be TCP-friendly, or not—a sender is said to be TCP-friendly if, under the same operating conditions, its long-term average send rate does not exceed that of a TCP sender. It is an established axiom that some senders in the Internet would need to be TCP-friendly. An equation-based rate control sender pl...

  17. Turning Traffic Jams to Jelly

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Beijing, known for having the worst traffic in China, is brewing up a traffic plan with the harshest ever measures to ensure smooth traffic flow as the capital’s gridlock during rush hour and private car sales soar.

  18. Observability of market daily volatility

    Science.gov (United States)

    Petroni, Filippo; Serva, Maurizio

    2016-02-01

    We study the price dynamics of 65 stocks from the Dow Jones Composite Average from 1973 to 2014. We show that it is possible to define a Daily Market Volatility σ(t) which is directly observable from data. This quantity is usually indirectly defined by r(t) = σ(t) ω(t) where the r(t) are the daily returns of the market index and the ω(t) are i.i.d. random variables with vanishing average and unitary variance. The relation r(t) = σ(t) ω(t) alone is unable to give an operative definition of the index volatility, which remains unobservable. On the contrary, we show that using the whole information available in the market, the index volatility can be operatively defined and detected.

  19. Road Traffic in China

    NARCIS (Netherlands)

    Jie, L.; Van Zuylen, H.J.

    2014-01-01

    Traffic is tightly related to the social and economic development in a country. In China the development of the economy has been very fast in the past 30 years and this is still continuing. The transport infrastructure shows a similar pattern, while traffic is also rapidly growing. In urban areas th

  20. Distraction in traffic.

    NARCIS (Netherlands)

    2013-01-01

    Many drivers, as well as cyclists and pedestrians, are occupied with all kinds of activities that can distract their attention from traffic, like listening to music, conducting a conversation on their mobile phone, or texting. Distraction has negative effects on traffic behaviour. Most studies estim

  1. Traffic Light Options

    DEFF Research Database (Denmark)

    Jørgensen, Peter Løchte

    This paper introduces, prices, and analyzes traffic light options. The traffic light option is an innovative structured OTC derivative developed independently by several London-based investment banks to suit the needs of Danish life and pension (L&P) companies, which must comply with the traffic...... light solvency stress test system introduced by the Danish Financial Supervisory Authority (DFSA) in June 2001. This monitoring system requires L&P companies to submit regular reports documenting the sensitivity of the companies' base capital to certain pre-defined market shocks - the red and yellow...... light scenarios. These stress scenarios entail drops in interest rates as well as in stock prices, and traffic light options are thus designed to pay off and preserve sufficient capital when interest rates and stock prices fall simultaneously. Sweden's FSA implemented a traffic light system in January...

  2. Traffic Light Options

    DEFF Research Database (Denmark)

    Jørgensen, Peter Løchte

    2007-01-01

    This paper introduces, prices, and analyzes traffic light options. The traffic light option is an innovative structured OTC derivative developed independently by several London-based investment banks to suit the needs of Danish life and pension (L&P) companies, which must comply with the traffic...... light solvency stress test system introduced by the Danish Financial Supervisory Authority (DFSA) in June 2001. This monitoring system requires L&P companies to submit regular reports documenting the sensitivity of the companies' base capital to certain pre-defined market shocks - the red and yellow...... light scenarios. These stress scenarios entail drops in interest rates as well as in stock prices, and traffic light options are thus designed to pay off and preserve sufficient capital when interest rates and stock prices fall simultaneously. Sweden's FSA implemented a traffic light system in January...

  3. Properties of Traffic Risk Coefficient

    Institute of Scientific and Technical Information of China (English)

    TANG Tie-Qiao; HUANG Hai-Jun; SHANG Hua-Yan; XUE Yu

    2009-01-01

    We use the model with the consideration of the traffic interruption probability (Physica A 387(2008)6845) to study the relationship between the traffic risk coefficient and the traffic interruption probability.The analytical and numerical results show that the traffic interruption probability will reduce the traffic risk coefficient and that the reduction is related to the density, which shows that this model can improve traffic security.

  4. A macroscopic model of traffic jams in axons.

    Science.gov (United States)

    Kuznetsov, A V; Avramenko, A A

    2009-04-01

    The purpose of this paper is to develop a minimal macroscopic model capable of explaining the formation of traffic jams in fast axonal transport. The model accounts for the decrease of the number density of positively (and negatively) oriented microtubules near the location of the traffic jam due to formation of microtubule swirls; the model also accounts for the reduction of the effective velocity of organelle transport in the traffic jam region due to organelles falling off microtubule tracks more often in the swirl region. The model is based on molecular-motor-assisted transport equations and the hydrodynamic model of traffic jams in highway traffic. Parametric analyses of the model's predictions for various values of viscosity of the traffic flow, variance of the velocity distribution, diffusivity of microtubule-bound and free organelles, rate constants for binding to and detachment from microtubules, relaxation time, and average motor velocities of the retrograde and anterograde transport, are carried out.

  5. Reducing OR Traffic Using Education, Policy Development, and Communication Technology.

    Science.gov (United States)

    Esser, Jennifer; Shrinski, Keonemana; Cady, Rhonda; Belew, John

    2016-01-01

    A bundled approach to surgical site infection (SSI) prevention strategies includes reducing OR traffic. A nurse-led quality improvement (QI) team sought to reduce OR traffic through education and a process change that included wireless communication technology and policy development. The team measured OR traffic by counting the frequency of door openings per hour in seven surgical suites during 305 surgical procedures conducted during similar 22-week periods before and after the QI project intervention. Door openings decreased significantly (P < 0.05) from an average of 37.8 per hour to 32.8 per hour after the QI project intervention. This suggests that our multifaceted approach reduces OR traffic. The next steps of this project include analyzing automatically captured video to understand OR traffic patterns and expanding education to departments and external personnel frequently present in our surgical suites. Future research evaluating the effectiveness of this OR traffic initiative on SSI incidence is recommended.

  6. CDC WONDER: Daily Air Temperatures and Heat Index

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Daily Air Temperature and Heat Index data available on CDC WONDER are county-level daily average air temperatures and heat index measures spanning the years...

  7. Daily Weather Records

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These daily weather records were compiled from a subset of stations in the Global Historical Climatological Network (GHCN)-Daily dataset. A weather record is...

  8. A novel car following model considering average speed of preceding vehicles group

    Science.gov (United States)

    Sun, Dihua; Kang, Yirong; Yang, Shuhong

    2015-10-01

    In this paper, a new car following model is presented by considering the average speed effect of preceding vehicles group in cyber-physical systems (CPS) environment. The effect of this new consideration upon the stability of traffic flow is examined through linear stability analysis. A modified Korteweg-de Vries (mKdV) equation was derived via nonlinear analysis to describe the propagating behavior of traffic density wave near the critical point. Good agreement between the simulation and the analytical results shows that average speed of preceding vehicles group leads to the stabilization of traffic systems, and thus can efficiently suppress the emergence of traffic jamming.

  9. Identifying file-sharing P2P traffic based on traffic characteristics

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    This article focuses on identifying file-sharing peer-to-peer (P2P) (such as BitTorrent (BT)) traffic at the borders of a stub network. By analyzing protocols and traffic of applications, it is found that file-sharing P2P traffic of a single user differs greatly from traditional and other P2P (such as QQ) applications' traffic in the distribution of involved remote hosts and remote ports. Therefore, a method based on discreteness of remote hosts (RHD) and discreteness of remote ports (RPD) is proposed to identify BT-like traffic. This method only relies on flow information of each user host in a stub network, and no packet payload needs to be monitored. At intervals, instant RHD for concurrent transmission control protocol and user datagram protocol flows for each host are calculated respectively through grouping flows by the stub network that the remote host of each flow belongs to. On given conditions, instant RPD are calculated through grouping flows by the remote port to amend instant RHD. Whether a host has been using a BT-like application or not can be deduced from instant RHD or average RHD for a period of time. The proposed method based on traffic characteristics is more suitable for identifying protean file-sharing P2P traffic than content-based methods. Experimental results show that this method is effective with high accuracy.

  10. Road traffic impact on urban water quality: a step towards integrated traffic, air and stormwater modelling.

    Science.gov (United States)

    Fallah Shorshani, Masoud; Bonhomme, Céline; Petrucci, Guido; André, Michel; Seigneur, Christian

    2014-04-01

    Methods for simulating air pollution due to road traffic and the associated effects on stormwater runoff quality in an urban environment are examined with particular emphasis on the integration of the various simulation models into a consistent modelling chain. To that end, the models for traffic, pollutant emissions, atmospheric dispersion and deposition, and stormwater contamination are reviewed. The present study focuses on the implementation of a modelling chain for an actual urban case study, which is the contamination of water runoff by cadmium (Cd), lead (Pb), and zinc (Zn) in the Grigny urban catchment near Paris, France. First, traffic emissions are calculated with traffic inputs using the COPERT4 methodology. Next, the atmospheric dispersion of pollutants is simulated with the Polyphemus line source model and pollutant deposition fluxes in different subcatchment areas are calculated. Finally, the SWMM water quantity and quality model is used to estimate the concentrations of pollutants in stormwater runoff. The simulation results are compared to mass flow rates and concentrations of Cd, Pb and Zn measured at the catchment outlet. The contribution of local traffic to stormwater contamination is estimated to be significant for Pb and, to a lesser extent, for Zn and Cd; however, Pb is most likely overestimated due to outdated emissions factors. The results demonstrate the importance of treating distributed traffic emissions from major roadways explicitly since the impact of these sources on concentrations in the catchment outlet is underestimated when those traffic emissions are spatially averaged over the catchment area.

  11. Aggregation and Averaging.

    Science.gov (United States)

    Siegel, Irving H.

    The arithmetic processes of aggregation and averaging are basic to quantitative investigations of employment, unemployment, and related concepts. In explaining these concepts, this report stresses need for accuracy and consistency in measurements, and describes tools for analyzing alternative measures. (BH)

  12. Analysis of average density difference effect in a new two-lane lattice model

    Science.gov (United States)

    Zhang, Geng; Sun, Di-Hua; Zhao, Min; Liu, Wei-Ning; Cheng, Sen-Lin

    2015-11-01

    A new lattice model is proposed by taking the average density difference effect into account for two-lane traffic system according to Transportation Cyber-physical Systems. The influence of average density difference effect on the stability of traffic flow is investigated through linear stability theory and nonlinear reductive perturbation method. The linear analysis results reveal that the unstable region would be reduced by considering the average density difference effect. The nonlinear kink-antikink soliton solution derived from the mKdV equation is analyzed to describe the properties of traffic jamming transition near the critical point. Numerical simulations confirm the analytical results showing that traffic jam can be suppressed efficiently by considering the average density difference effect for two-lane traffic system.

  13. On Averaging Rotations

    DEFF Research Database (Denmark)

    Gramkow, Claus

    1999-01-01

    In this article two common approaches to averaging rotations are compared to a more advanced approach based on a Riemannian metric. Very offten the barycenter of the quaternions or matrices that represent the rotations are used as an estimate of the mean. These methods neglect that rotations belong...... approximations to the Riemannian metric, and that the subsequent corrections are inherient in the least squares estimation. Keywords: averaging rotations, Riemannian metric, matrix, quaternion...

  14. VBR video traffic models

    CERN Document Server

    Tanwir, Savera

    2014-01-01

    There has been a phenomenal growth in video applications over the past few years. An accurate traffic model of Variable Bit Rate (VBR) video is necessary for performance evaluation of a network design and for generating synthetic traffic that can be used for benchmarking a network. A large number of models for VBR video traffic have been proposed in the literature for different types of video in the past 20 years. Here, the authors have classified and surveyed these models and have also evaluated the models for H.264 AVC and MVC encoded video and discussed their findings.

  15. Road Traffic Injuries

    Institute of Scientific and Technical Information of China (English)

    WANG Zheng-guo

    2005-01-01

    @@ As everybody knows that automobiles have been greatly changing our life. However, everything has two sides, motor vehicles have also caused a huge number of people's deaths, injuries and property damage. Traffic crashes are perhaps the number one public health problem in developed countries [1]. In the United States, pre-retirement years of life lost in traffic crashes are more than that of the two combined leading diseases: cancer and heart disease [1]. Today road traffic crash (RTC) ranks 11th in leading cause of death and accounts for 2.1% of all deaths globally.

  16. Self-organized Natural Roads for Predicting Traffic Flow: A Sensitivity Study

    CERN Document Server

    Jiang, Bin; Yin, Junjun

    2008-01-01

    In this paper, we extended road-based topological analysis into both nationwide and urban road networks, and concentrated on a sensitivity study with respect to the formation of self-organized natural roads based on Gestalt principle of good continuity. Both Annual Average Daily Traffic (AADT) and Global Positioning System (GPS) data were used to correlate with a series of ranking metrics including five centrality-based metrics and two PageRank metrics. It was found that there exists a tipping point from segment- to road-based network topology in terms of correlation between ranking metrics and their traffic. To our big surprise, (1) this correlation is significantly improved if a selfish rather than utopian strategy is adopted in forming the self-organized natural roads, and (2) point-based metrics assigned by summation into individual roads tend to have a much better correlation with traffic flow than line-based metrics. These counter-intuitive surprising findings constitute emergent properties of self-orga...

  17. Safety Impacts of Push-Button and Countdown Timer on Nonmotorized Traffic at Intersections

    Directory of Open Access Journals (Sweden)

    Bei Zhou

    2014-01-01

    Full Text Available This paper applies the random parameters negative binominal model to investigate safety impacts of push-button and countdown timer on pedestrians and cyclists at urban intersections. To account for possible unobserved heterogeneity which could vary from one intersection to another, random parameters model is introduced. A simulation-based maximum likelihood method using Halton draws is applied to estimate the maximum likelihood of random parameters in the model. Dataset containing pedestrians’ and cyclists’ crash data of 1,001 intersections from Chicago is utilized to establish the statistical relationship between crash frequencies and potential impact factors. LIMDEP (Version 9.0 statistical package is utilized for modeling. The parameter estimation results indicate that existence of push-button and countdown timer could significantly reduce crash frequencies of pedestrians and cyclists at intersections. Increasing number of through traffic lanes, left turn lanes, and ratio of major direction AADT to minor direction AADT, tend to increase crash frequencies. Annual average daily left turn traffic has a negative impact on pedestrians’ safety, but its impact on cyclists’ crash frequency is statistically insignificant at 90% confidence level. The results of current study could provide important insights for nonmotorized traffic safety improvement projects in both planning and operational levels.

  18. Turning Traffic Jams to Jelly

    Institute of Scientific and Technical Information of China (English)

    LI LI

    2010-01-01

    @@ Beijing, known for having the worst traffic in China, is brewing up a traffic plan with the harshest ever measures to ensure smooth traffic flow as the capital's gridlock during rush hour and private car sales soar. On December 13, the Beijing Municipal Government started soliciting public opinions for a draft plan designed to relieve the city's traffic problems.

  19. Allegheny County Traffic Counts

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Traffic sensors at over 1,200 locations in Allegheny County collect vehicle counts for the Pennsylvania Department of Transportation. Data included in the Health...

  20. Ethernet traffic measurement

    OpenAIRE

    Santschi, Yann; Corthay, François

    2012-01-01

    The goal of this project is to create a FPGA Ethernet traffic measurement point and interface it with an existing measurement network, named DPMI, that is developed in Blekinge Institute of Technology.

  1. Non-Traffic Citations

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Non-traffic citations (NTCs, also known as "summary offenses") document low-level criminal offenses where a law enforcement officer or other authorized official...

  2. Digital Daily Cycles of Individuals

    Directory of Open Access Journals (Sweden)

    Talayeh eAledavood

    2015-10-01

    Full Text Available Humans, like almost all animals, are phase-locked to the diurnal cycle. Most of us sleep at night and are active through the day. Because we have evolved to function with this cycle, the circadian rhythm is deeply ingrained and even detectable at the biochemical level. However, within the broader day-night pattern, there are individual differences: e.g., some of us are intrinsically morning-active, while others prefer evenings. In this article, we look at digital daily cycles: circadian patterns of activity viewed through the lens of auto-recorded data of communication and online activity. We begin at the aggregate level, discuss earlier results, and illustrate differences between population-level daily rhythms in different media. Then we move on to the individual level, and show that there is a strong individual-level variation beyond averages: individuals typically have their distinctive daily pattern that persists in time. We conclude by discussing the driving forces behind these signature daily patterns, from personal traits (morningness/eveningness to variation in activity level and external constraints, and outline possibilities for future research.

  3. Your Average Nigga

    Science.gov (United States)

    Young, Vershawn Ashanti

    2004-01-01

    "Your Average Nigga" contends that just as exaggerating the differences between black and white language leaves some black speakers, especially those from the ghetto, at an impasse, so exaggerating and reifying the differences between the races leaves blacks in the impossible position of either having to try to be white or forever struggling to…

  4. On Averaging Rotations

    DEFF Research Database (Denmark)

    Gramkow, Claus

    2001-01-01

    In this paper two common approaches to averaging rotations are compared to a more advanced approach based on a Riemannian metric. Very often the barycenter of the quaternions or matrices that represent the rotations are used as an estimate of the mean. These methods neglect that rotations belong...

  5. MRO SOW Daily Script

    Science.gov (United States)

    Fisher, Forest E.; Khanampornpan, Teerapat; Gladden, Roy E.

    2008-01-01

    The MRO SOW daily script (wherein "MRO" signifies "Mars Reconnaissance Orbiter" and "SOW" signifies "sequence systems engineer of the week") is a computer program that automates portions of the MRO daily SOW procedure, which includes checking file-system sizes and automated sequence processor (ASP) log files. The MRO SOW daily script effects clear reporting of (1) the status of, and requirements imposed on, the file system and (2) the ASP log files.

  6. SPACE TOURISM ORGANIZATION AND ADMINISTRATIVE ARRANGEMENT OF TOURIST TRAFFIC ANALYSIS BY LOCALITY BUŞTENI

    Directory of Open Access Journals (Sweden)

    Adelaida Cristina HONTUS

    2013-12-01

    Full Text Available In order to achieve the best possible tourist activity it is needed that besides natural resources and human and material resources to be able to satisfy the tourist requirements. These material resourcess are known as “material and technical basis". This is represented by: accommodation and food, transportation, treatment and leisure facilities and is primarily conditioned by the development and modernization of existing material and technical basis. Thus, a highly attractive tourist area can not be on offer before receiving the facilities for receiving and retaining travelers. Buşteni, resort includes Poiana Ţapului,s dominated by steep Bucegi and has a great starting point for ascents, but it is also a true spa, indicated not only for leisure but also for the treatment of diseases of debility, physical and mental fatigue and digestive disorders and glands. Most representative indicators commonly used to express movement and travel and its main characteristics are: number of urge tourists, average daily number of tourists, number of days / tourist, average length of stay, receipts from tourism and tourist traffic density, tourists’ relative preferences. Analysis of tourist traffic in the tourist areas of Buşteni will be achieved by calculating these indicators. Tourist traffic indicators reflect the distribution and evolution in time of tourism internal and external demand,. They also reflect the behavior of the application on the use of vehicles and equipment and can be used for studying the origin and destination of tourism demand, the average stay and fidelity to a particular destination.

  7. MOPITT Gridded Daily CO Retrievals (Near Infrared Radiances) V006

    Data.gov (United States)

    National Aeronautics and Space Administration — This product averages the daily L2 swath data into a 1x1 degree grid. Day and night passes are kept separate. Averaging kernels for each retrieval are provided...

  8. MOPITT Gridded Daily CO Retrievals (Near Infrared Radiances) V005

    Data.gov (United States)

    National Aeronautics and Space Administration — This product averages the daily L2 swath data into a 1x1 degree grid. Day and night passes are kept separate. Averaging kernels for each retrieval are provided...

  9. MOPITT Gridded Daily CO Retrievals (Thermal Infrared Radiances) V005

    Data.gov (United States)

    National Aeronautics and Space Administration — This product averages the daily L2 swath data into a 1x1 degree grid. Day and night passes are kept separate. Averaging kernels for each retrieval are provided...

  10. Assessment of network traffic congestion through Traffic Congestability Value (TCV: a new index

    Directory of Open Access Journals (Sweden)

    Patel Nilanchal

    2015-12-01

    Full Text Available Traffic congestion is a major and growing problem in urban areas across the globe. It reduces the effective spatial interaction between different locations. To mitigate traffic congestion, not only the actual status of different routes needs to be known but also it is imperative to determine network congestion in different spatial zones associated with distinct land use classes. In the present paper, a new formula is proposed to quantify traffic congestion in the different spatial zones of a study area characterized by distinct land use classes. The proposed formula is termed the Traffic Congestability Value (TCV. The formula considers three major influencing factors: congestion index value, pedestrian movement and road surface conditions; since these parameters are significantly related to land use in a region. The different traffic congestion parameters, i.e. travel time, average speed and the proportion of time stopped, were collected in real time. Lower values of TCV correspond to a higher degree of congestion in the respective spatial zones and vice-versa and the results were validated in the field. TCV differs from the previous approaches to quantifying traffic congestion since it focuses on the causes of network congestion while in previous works the focus was generally on link flow congestion.

  11. The Physics of Traffic and Regional Development

    CERN Document Server

    Helbing, Dirk

    2013-01-01

    This contribution summarizes and explains various principles from physics which are used for the simulation of traffic flows in large street networks, the modeling of destination, transport mode, and route choice, or the simulation of urban growth and regional development. The methods stem from many-particle physics, from kinetic gas theory, or fluiddynamics. They involve energy and entropy considerations, transfer the law of gravity, apply cellular automata and require methods from evolutionary game theory. In this way, one can determine interaction forces among driver-vehicle units, reproduce breakdowns of traffic including features of synchronized congested flow, or understand changing usage patterns of alternative roads. One can also describe daily activity patterns based on decision models, simulate migration streams, and model urban growth as a particular kind of aggregation process.

  12. Influence of periodic traffic congestion on epidemic spreading

    Science.gov (United States)

    Zheng, Muhua; Ruan, Zhongyuan; Tang, Ming; Do, Younghae; Liu, Zonghua

    2016-11-01

    In the metropolis, traffic congestion has become a very serious problem, especially in rush hours. This congestion causes people to have more chance to contact each other and thus will accelerate epidemic spreading. To explain this observation, we present a reaction-diffusion (RD) model with a periodic varying diffusion rate to represent the daily traveling behaviors of human beings and its influence to epidemic spreading. By extensive numerical simulations, we find that the epidemic spreading can be significantly influenced by traffic congestion where the amplitude, period and duration of diffusion rate are the three key parameters. Furthermore, a brief theory is presented to explain the effects of the three key parameters. These findings suggest that except the normal ways of controlling contagion in working places and long-distance traveling, controlling the contagion in daily traffic congestion may be another effective way to reduce epidemic spreading.

  13. THE INFLUENCE OF THE MAIN PARAMETERS OF TRAIN TRAFFIC VOLUME ON TOTAL PROFITS OF RAILWAYS

    Directory of Open Access Journals (Sweden)

    H. YA. Mozolevich

    2015-04-01

    Full Text Available Purpose. The paper is aimed to influence analysis of parameters such as the number of trains on the section and the length of freight trains, the total profit of the railway and determination of total profit of Prydniprovsk railway for major parts of the trains handling; the determination of the specific rate of return on 1 kilometer operational length of each individual link in the rail network. Methodology. To achieve this goal the simulation models of the sections of railway polygon and the simulation of cargo trains have been developed. On the basis of obtained results the dependence of the main parameters of train traffic and their impact on the overall profit of the railway was determined. Findings. On the basis of the conducted studies the functions operating costs for each section were developed to determine the optimal routes crossing of trains and choice of rational parameters. The operating costs, revenue, total profit of railways and certain impact parameters of train traffic volume on the economic performance of railway transport were calculated with their help. It is determined that freight trains, length 53-56 of a conventional car is optimal to pass and loading area should be 75-85% of the available crossing capacity. Taking into account given results, the electrification of the sections with diesel traction (due to the significant cost of diesel fuel is the priority development of railway transport at the possible increase in size of the movement. Originality. Authors have improved the technology of determining the total profits of railways on the basis of variables train traffic volumes. For the first time the specific rate of profit on the 1 kilometer operational length of the section depending on the size of the average daily traffic is identified and proposed to use to determine the investment attractiveness of the railways. The simulation models of individual sections of the real train polygon at Prydniprovsk railway were

  14. International Space Station Alpha (ISSA) Integrated Traffic Model

    Science.gov (United States)

    Gates, R. E.

    1995-01-01

    The paper discusses the development process of the International Space Station Alpha (ISSA) Integrated Traffic Model which is a subsystem analyses tool utilized in the ISSA design analysis cycles. Fast-track prototyping of the detailed relationships between daily crew and station consumables, propellant needs, maintenance requirements and crew rotation via spread sheets provide adequate benchmarks to assess cargo vehicle design and performance characteristics.

  15. Negative Average Preference Utilitarianism

    Directory of Open Access Journals (Sweden)

    Roger Chao

    2012-03-01

    Full Text Available For many philosophers working in the area of Population Ethics, it seems that either they have to confront the Repugnant Conclusion (where they are forced to the conclusion of creating massive amounts of lives barely worth living, or they have to confront the Non-Identity Problem (where no one is seemingly harmed as their existence is dependent on the “harmful” event that took place. To them it seems there is no escape, they either have to face one problem or the other. However, there is a way around this, allowing us to escape the Repugnant Conclusion, by using what I will call Negative Average Preference Utilitarianism (NAPU – which though similar to anti-frustrationism, has some important differences in practice. Current “positive” forms of utilitarianism have struggled to deal with the Repugnant Conclusion, as their theory actually entails this conclusion; however, it seems that a form of Negative Average Preference Utilitarianism (NAPU easily escapes this dilemma (it never even arises within it.

  16. Urban Traffic Signal System Control Structural Optimization Based on Network Analysis

    Directory of Open Access Journals (Sweden)

    Li Wang

    2013-01-01

    Full Text Available Advanced urban traffic signal control systems such as SCOOT and SCATS normally coordinate traffic network using multilevel hierarchical control mechanism. In this mechanism, several key intersections will be selected from traffic signal network and the network will be divided into different control subareas. Traditionally, key intersection selection and control subareas division are executed according to dynamic traffic counts and link length between intersections, which largely rely on traffic engineers’ experience. However, it omits important inherent characteristics of traffic network topology. In this paper, we will apply network analysis approach into these two aspects for traffic system control structure optimization. Firstly, the modified C-means clustering algorithm will be proposed to assess the importance of intersections in traffic network and furthermore determine the key intersections based on three indexes instead of merely on traffic counts in traditional methods. Secondly, the improved network community discovery method will be used to give more reasonable evidence in traffic control subarea division. Finally, to test the effectiveness of network analysis approach, a hardware-in-loop simulation environment composed of regional traffic control system, microsimulation software and signal controller hardware, will be built. Both traditional method and proposed approach will be implemented on simulation test bed to evaluate traffic operation performance indexes, for example, travel time, stop times, delay and average vehicle speed. Simulation results show that the proposed network analysis approach can improve the traffic control system operation performance effectively.

  17. A COMPACT MODEL FOR PREDICTING ROAD TRAFFIC NOISE

    Directory of Open Access Journals (Sweden)

    R. Golmohammadi ، M. Abbaspour ، P. Nassiri ، H. Mahjub

    2009-07-01

    Full Text Available Noise is one of the most important sources of pollution in the metropolitan areas. The recognition of road traffic noise as one of the main sources of environmental pollution has led to develop models that enable us to predict noise level from fundamental variables. Traffic noise prediction models are required as aids in the design of roads and sometimes in the assessment of existing, or envisaged changes in, traffic noise conditions. The purpose of this study was to design a prediction road traffic noise model from traffic variables and conditions of transportation in Iran.This paper is the result of a research conducted in the city of Hamadan with the ultimate objective of setting up a traffic noise model based on the traffic conditions of Iranian cities. Noise levels and other variables have been measured in 282 samples to develop a statistical regression model based on A-weighted equivalent noise level for Iranian road condition. The results revealed that the average LAeq in all stations was 69.04± 4.25 dB(A, the average speed of vehicles was 44.57±11.46 km/h and average traffic load was 1231.9 ± 910.2 V/h.The developed model has seven explanatory entrance variables in order to achieve a high regression coefficient (R2=0.901. Comparing means of predicted and measuring equivalent sound pressure level (LAeq showed small difference less than -0.42 dB(A and -0.77 dB(A for Tehran and Hamadan cities, respectively. The suggested road traffic noise model can be effectively used as a decision support tool for predicting equivalent sound pressure level index in the cities of Iran.

  18. Winning strategies in congested traffic

    CERN Document Server

    Jarai-Szabo, Ferenc

    2012-01-01

    One-directional traffic on two-lanes is modeled in the framework of a spring-block type model. A fraction $q$ of the cars are allowed to change lanes, following simple dynamical rules, while the other cars keep their initial lane. The advance of cars, starting from equivalent positions and following the two driving strategies is studied and compared. As a function of the parameter $q$ the winning probability and the average gain in the advancement for the lane-changing strategy is computed. An interesting phase-transition like behavior is revealed and conclusions are drawn regarding the conditions when the lane changing strategy is the better option for the drivers.

  19. Traffic Light Detection

    DEFF Research Database (Denmark)

    Philipsen, Mark Philip; Jensen, Morten Bornø; Møgelmose, Andreas

    2015-01-01

    Traffic light recognition (TLR) is an integral part of any intelligent vehicle, which must function in the existing infrastructure. Pedestrian and sign detection have recently seen great improvements due to the introduction of learning based detectors using integral channel features. A similar push...... database is collected based on footage from US roads. The database consists of both test and training data, totaling 46,418 frames and 112,971 annotated traffic lights, captured in continuous sequences under a varying light and weather conditions. The learning based detector achieves an AUC of 0.4 and 0...

  20. Generalized Deterministic Traffic Rules

    CERN Document Server

    Fuks, H; Fuks, Henryk; Boccara, Nino

    1997-01-01

    We study a family of deterministic models for highway traffic flow which generalize cellular automaton rule 184. This family is parametrized by the speed limit $m$ and another parameter $k$ that represents a ``degree of aggressiveness'' in driving, strictly related to the distance between two consecutive cars. We compare two driving strategies with identical maximum throughput: ``conservative'' driving with high speed limit and ``aggressive'' driving with low speed limit. Those two strategies are evaluated in terms of accident probability. We also discuss fundamental diagrams of generalized traffic rules and examine limitations of maximum achievable throughput. Possible modifications of the model are considered.

  1. Constructing a Traffic Information Providing System Utilizing Multi-Source Information

    Science.gov (United States)

    Tamaki, Hiroshi; Yano, Junji; Kagawa, Kouji; Morita, Tetsuo; Numao, Masayuki; Kurihara, Satoshi

    To realize an effective ITS(Intelligent Transport Systems) services, such as a traffic jam prediction system or car navigation system, the traffic information like average traffic speed is indispensable. However, current systems providing traffic information have serious problems about lack of data. Hence, we construct a system which provides traffic information, which complements lack data using incomplete probe and VICS(Vehicle Information and Communication System) data. The system utilizes multi-information such as real time/stored/diffusion/succession information effectively. We verified the performance of the system through experiments using probe/VICS data of Nagoya city, and confirmed beneficial results.

  2. Daily Weather Maps

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Several different government offices have published the Daily weather maps over its history. The publication has also gone by different names over time. The U.S....

  3. Lightship Daily Observations

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Observations taken on board lightships along the United States coasts from 1936 - 1983. Generally 4-6 observations daily. Also includes deck logs, which give...

  4. DailyMed Webservices

    Data.gov (United States)

    U.S. Department of Health & Human Services — The DailyMed RESTful API is a web service for accessing current SPL information. It is implemented using HTTP and can be thought of as a collection of resources,...

  5. Tips for Daily Living

    Science.gov (United States)

    ... Tips and Gadgets for Daily Activities Dressing Tips Shopping Tips Modifying the Bathroom Driving After Stroke Medication ... and resources. Find a group in your area . Online Support If there is not a support group ...

  6. DailyMed

    Data.gov (United States)

    U.S. Department of Health & Human Services — DailyMed provides high quality information about marketed drugs. This information includes FDA labels (package inserts). This Web site provides health information...

  7. Dementia - daily care

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000030.htm Dementia - daily care To use the sharing features on ... prevent choking. Tips for Talking With Someone With Dementia Keep distractions and noise down: Turn off the ...

  8. Relationship Between Air Pollution, Weather, Traffic, and Traffic-Related Mortality

    Science.gov (United States)

    Dastoorpoor, Maryam; Idani, Esmaeil; Khanjani, Narges; Goudarzi, Gholamreza; Bahrampour, Abbas

    2016-01-01

    Background Air pollution and weather are just two of many environmental factors contributing to traffic accidents (RTA). Objectives This study assessed the effects of these factors on traffic accidents and related mortalities in Ahvaz, Iran. Methods In this ecological study, data about RTA, traffic-related mortalities, air pollution (including NO, CO, NO2, NOx PM10, SO2, and O3 rates) and climate data from March 2008 until March 2015 was acquired from the Khuzestan State Police Force, the Environmental Protection Agency and the State Meteorological Department. Statistical analysis was performed with STATA 12 through both crude and adjusted negative binomial regression methods. Results There was a significant positive correlation between increase in the monthly average temperature, the number of rainy days, and the number of frost days with the number of RTA (P < 0.05). Increased monthly average relative humidity, evaporation, and number of sunny days were negatively correlated with the frequency of RTA (P < 0.05). We also observed an inverse significant correlation between monthly average relative humidity, evaporation, and wind speed with traffic accident mortality (P < 0.05). Some air pollutants were negatively associated with the incidence rate of RTA. Conclusions It appears that some weather variables were significantly associated with increased RTA. However, increased levels of air pollutants were not associated with increased rates of RTA and/or related mortalities. Additional studies are recommended to explore this topic in more detail.

  9. Short-term traffic flow forecasting with A-SVARMA

    OpenAIRE

    2013-01-01

    PUBLISHED Short-term Traffic Flow Forecasting (STFF), the process of predicting future traffic conditions based on historical and real-time observations, is an essential aspect of Intelligent Transportation Systems (ITS). The existing well-known algorithms used for STFF include time-series analysis based techniques, among which the seasonal Autoregressive Moving Average (ARMA) model is one of the most precise methods used in this field. The effectiveness of STFF in an urban transport netwo...

  10. 2013 Traffic Safety Culture Index

    Science.gov (United States)

    ... death in the United States. 2013 Traffic Safety Culture Index January 2014 607 14th Street, NW, Suite ... org | 202-638-5944 Title 2013 Traffic Safety Culture Index (January 2014) About the Sponsor AAA Foundation ...

  11. Generic vehicle speed models based on traffic simulation: Development and application

    Energy Technology Data Exchange (ETDEWEB)

    Margiotta, R.; Cohen, H.; Elkins, G.; Rathi, A.; Venigalla, M.

    1994-12-15

    This paper summarizes the findings of a research project to develop new methods of estimating speeds for inclusion in the Highway Performance Monitoring System (HPMS) Analytical Process. The paper focuses on the effects of traffic conditions excluding incidents (recurring congestion) on daily average ed and excess fuel consumption. A review of the literature revealed that many techniques have been used to predict speeds as a function of congestion but most fail to address the effects of queuing. However, the method of Dowling and Skabardonis avoids this limitation and was adapted to the research. The methodology used the FRESIM and NETSIM microscopic traffic simulation models to develop uncongested speed functions and as a calibration base for the congested flow functions. The chief contributions of the new speed models are the simplicity of application and their explicit accounting for the effects of queuing. Specific enhancements include: (1) the inclusion of a queue discharge rate for freeways; (2) use of newly defined uncongested flow speed functions; (3) use of generic temporal distributions that account for peak spreading; and (4) a final model form that allows incorporation of other factors that influence speed, such as grades and curves. The main limitation of the new speed models is the fact that they are based on simulation results and not on field observations. They also do not account for the effect of incidents on speed. While appropriate for estimating average national conditions, the use of fixed temporal distributions may not be suitable for analyzing specific facilities, depending on observed traffic patterns. Finally, it is recommended that these and all future speed models be validated against field data where incidents can be adequately identified in the data.

  12. Chaotic Control of Network Traffic

    Institute of Scientific and Technical Information of China (English)

    YANG Tan; CUI Yi-Dong; JIN Yue-Hui; CHENG Shi-Duan

    2009-01-01

    A method of chaotic control on network traffic is presented.By this method,the chaotic network traffic can be controlled to a pre-assigned equilibrium point according to chaotic prediction and the largest Lyapunov exponent of the traffic on congested link is reduced,thereby the probability of traffic burst and network congestion can be reduced.Numerical examples show that this method is effective.

  13. The Classroom Traffic Jam

    Science.gov (United States)

    Edwards, Arthur W.

    1977-01-01

    The importance of energy conservation is developed in this simulation. Children draw an automobile and then are asked to drive it through the classroom roadways. When a traffic jam results, students offer ways to eliminate it. The importance of mass transportation and car pools is stressed by the teacher. (MA)

  14. Cyclists' Injuries in Traffic

    Directory of Open Access Journals (Sweden)

    Eduard Missoni

    2004-01-01

    Full Text Available Among numerous participants in road traffic there are alsothe cyclists. Cycling has become during the recent years one ofthe major components of the modem living, even in Croatia. Inalmost all the developed countries of the world, cycling isemphasised as an activity which improves health and contributesto the improvement of overall physical fitness and environmentalprotection. During the period between 1 January 1996and 31 December 1999, an analysis of the number of cyclist accidentsin road traffic was carried out. Special attention waspaid to the number of injured cyclists. In 1996, in road traffic,there were 1,218 cyclist accidents in which 912 (74.9% cyclistswere injured. In 1997, there were 1,146 incidents and accidents,with 854 (74.5% injured persons. In 1998, there were 1,167accidents, 887 (76.0% injured. In the last study in 1999, thetotal number of cyclist accidents amounted to 1,230, and thenumber of the injured cyclists was 924 (75.1% .Every event resulting in a more or less severe disability is agreat distress and great damage to every injured person as individualas well as for the family and eventually for the society asa whole. This paper recommends certain measures and proceduresthat should substantially reduce the traffic accidents andincidents which involve cyclists.

  15. Air Traffic Flow Management

    CERN Document Server

    Ganu, Hrishikesh V

    2008-01-01

    Air Traffic Flow Management is the regulation of air traffic in order to avoid exceeding airport or flight sector capacity in handling traffic, and to ensure that available capacity is used efficiently. We have tried to explore the logic behind the claims by Bertsimas et.al about integral solutions to the LP relaxation of the Traffic Flow Management Problem(TFMP). Polyhedral theory only indicates that the stronger TFMP formulation of Bertsimas et.al might lead to integral solutions in some cases. Our computations indicate that the encouraging results reported by Bertsimas et.al are not merely fortuitous or due to their specific data set. Indeed, we found that the TFMP had integral solutions even in case of artificial data sets generated to include severe conflicts in the flight schedules. In our limited tests with 4-5 scenarios, we obtained non-integral solutions only once. This is of significant practical importance because, the LP relaxation can be solved even on small machines with low memory and processor...

  16. ITSA: Internet Traffic Statistics Archive

    NARCIS (Netherlands)

    Hoogesteger, Martijn; Oliveira Schmidt, de Ricardo; Pras, Aiko

    2016-01-01

    Motivated by the fact that comprehensive and long term Internet traffic measurements can be hard to obtain, we have proposed and developed the Internet Traffic Statistics Archive (ITSA). Since 2013, ITSA concentrates reports on high-level statistics of Internet traffic worldwide. Examples of statist

  17. Pedalcylists. Traffic Safety Facts, 2000.

    Science.gov (United States)

    National Highway Traffic Safety Administration (DOT), Washington, DC.

    This document provides statistical information on traffic accidents involving U.S. bicyclists. Data include: (1) trends in pedalcyclist and total traffic fatalities, 1990-2000; (2) non-occupant traffic fatalities, 1990-2000; (3) pedalcyclists killed and injured, and fatality and injury rates, by age and sex, 2000; and (4) pedalcyclist traffic…

  18. Cost Estimation of Road Traffic Injuries Among Iranian Motorcyclists Using the Willingness to Pay Method

    Science.gov (United States)

    Ainy, Elaheh; Soori, Hamid; Ganjali, Mojtaba; Basirat, Behzad; Haddadi, Mashyaneh

    2016-01-01

    Background Motorcycle riders are amongst some of the most vulnerable road users. The burden of motorcycles injuries from low and middle income countries is under-reported. Objectives In this study, the cost of traffic injuries among motorcyclists was calculated using the willingness to pay (WTP) method in Iran in 2013. Patients and Methods In a cross-sectional study, 143 motorcyclists were randomly selected. The research questionnaire was prepared based on the standard WTP method [stated preference (SP), contingent value (CV) and revealed preference (RP) models] taking into consideration perceived risks, especially those in Iran. Data were collected by a scenario for motorcyclists. The criteria for inclusion in the study consisted of having at least a high school education and being in the age range of 18 - 65 years. The final analysis of the WTP data was performed using the Weibull model. Results The mean WTP was 888,110 IRR (Iranian Rial) among motorcyclists. The statistical value of life was estimated according to 4694 death cases as 3,146,225,350,943 IRR, which was equivalent to USD 104,874,178 based on the dollar free market rate of 30,000 IRR (purchasing power parity). The cost of injury was 6,903,839,551,000 IRR, equivalent to USD 230,127,985 (based upon 73,325 injured motorcyclists in 2013, a daily traffic volume of 311, and a daily payment of 12,110 IRR for 250 working days). In total, injury and death cases came to 10,050,094,901,943 IRR, equivalent to USD 335,003,163. Willingness to pay had a significant relationship with having experienced an accident, the length of the daily trip (in km), and helmet use (P < 0.001). Conclusions Willingness to pay can be affected by experiencing an accident, the distance of the daily trip, and helmet use. The cost of traffic injuries among motorcyclists shows that this rate is much higher than the global average. Thus, expenditure should be made on effective initiatives such as the safety of motorcyclists. PMID:27679784

  19. CONTROLLING TRAFFIC FLOW IN MULTILANE-ISOLATED INTERSECTION USING ANFIS APPROACH TECHNIQUES

    Directory of Open Access Journals (Sweden)

    G. R. LAI

    2015-08-01

    Full Text Available Many controllers have applied the Adaptive Neural-Fuzzy Inference System (ANFIS concept for optimizing the controller performance. However, there are less traffic signal controllers developed using the ANFIS concept. ANFIS traffic signal controller with its fuzzy rule base and its ability to learn from a set of sample data could improve the performance of Existing traffic signal controlling system to reduce traffic congestions at most of the busy traffic intersections in city such as Kuala Lumpur, Malaysia. The aim of this research is to develop an ANFIS traffic signals controller for multilane-isolated four approaches intersections in order to ease traffic congestions at traffic intersections. The new concept to generate sample data for ANFIS training is introduced in this research. The sample data is generated based on fuzzy rules and can be analysed using tree diagram. This controller is simulated on multilane-isolated traffic intersection model developed using M/M/1 queuing theory and its performance in terms of average waiting time, queue length and delay time are compared with traditional controllers and fuzzy controller. Simulation result shows that the average waiting time, queue length, and delay time of ANFIS traffic signal controller are the lowest as compared to the other three controllers. In conclusion, the efficiency and performance of ANFIS controller are much better than that of fuzzy and traditional controllers in different traffic volumes.

  20. Cellular automata models for synchronized traffic flow

    CERN Document Server

    Jiang Rui

    2003-01-01

    This paper presents a new cellular automata model for describing synchronized traffic flow. The fundamental diagrams, the spacetime plots and the 1 min average data have been analysed in detail. It is shown that the model can describe the outflow from the jams, the light synchronized flow as well as heavy synchronized flow with average speed greater than approximately 24 km h sup - sup 1. As for the synchronized flow with speed lower than 24 km h sup - sup 1 , it is unstable and will evolve into the coexistence of jams, free flow and light synchronized flow. This is consistent with the empirical findings (Kerner B S 1998 Phys. Rev. Lett. 81 3797).

  1. City traffic jam relief by stochastic resonance

    Science.gov (United States)

    Castillo, F.; Toledo, B. A.; Muñoz, V.; Rogan, J.; Zarama, R.; Kiwi, M.; Valdivia, J. A.

    2014-06-01

    We simulate traffic in a city by means of the evolution of a row of interacting cars, using a cellular automaton model, in a sequence of traffic lights synchronized by a "green wave". When our initial condition is a small density jammed state, its evolution shows the expected scaling laws close to the synchronization resonance, with a uniform car density along the street. However, for an initial large density jammed state, we observe density variations along the streets, which results in the breakdown of the scaling laws. This spatial disorder corresponds to a different attractor of the system. As we include velocity perturbations in the dynamics of the cars, all these attractors converge to a statistically equivalent system for all initial jammed densities. However, this emergent state shows a stochastic resonance-like behavior in which the average traffic velocity increases with respect to that of the system without noise, for several initial jammed densities. This result may help in the understanding of dynamics of traffic jams in cities.

  2. Effects of Traffic Lights on CA Traffic Model

    Institute of Scientific and Technical Information of China (English)

    SuweiFENG; GuoqingGU

    1997-01-01

    Cellular automaton traffic models can include various factors in traffic system with simple regulations and the corresponding computations and simulations are rather convenient and effective.In this paper,the Biham-Middleton-Levine model(briefly saying the BML model)is improved by removing its limitation of synchronized change of traffic lights.In new model,the traffic light at each crossing could arbitrarily change its starting time and tempo of variation and hence the model could more realistically describe the influence of traffic lights on the performance of traffic systems.The cases of traffic light with unsynchronized starting time and different tempo of variation are simulated in this paper.

  3. Chronic daily headaches

    Directory of Open Access Journals (Sweden)

    Fayyaz Ahmed

    2012-01-01

    Full Text Available Chronic Daily Headache is a descriptive term that includes disorders with headaches on more days than not and affects 4% of the general population. The condition has a debilitating effect on individuals and society through direct cost to healthcare and indirectly to the economy in general. To successfully manage chronic daily headache syndromes it is important to exclude secondary causes with comprehensive history and relevant investigations; identify risk factors that predict its development and recognise its sub-types to appropriately manage the condition. Chronic migraine, chronic tension-type headache, new daily persistent headache and medication overuse headache accounts for the vast majority of chronic daily headaches. The scope of this article is to review the primary headache disorders. Secondary headaches are not discussed except medication overuse headache that often accompanies primary headache disorders. The article critically reviews the literature on the current understanding of daily headache disorders focusing in particular on recent developments in the treatment of frequent headaches.

  4. Global Historical Climatology Network - Daily (GHCN-Daily), Version 3

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Global Historical Climatology Network - Daily (GHCN-Daily) dataset integrates daily climate observations from approximately 30 different data sources. Version 3...

  5. Human activity under high pressure: A case study on fluctuation scaling of air traffic controller's communication behaviors

    Science.gov (United States)

    Wang, Yanjun; Zhang, Qiqian; Zhu, Chenping; Hu, Minghua; Duong, Vu

    2016-01-01

    Recent human dynamics research has unmasked astonishing statistical characteristics such as scaling behaviors in human daily activities. However, less is known about the general mechanism that governs the task-specific activities. In particular, whether scaling law exists in human activities under high pressure remains an open question. In air traffic management system, safety is the most important factor to be concerned by air traffic controllers who always work under high pressure, which provides a unique platform to study human activity. Here we extend fluctuation scaling method to study air traffic controller's communication activity by investigating two empirical communication datasets. Taken the number of controlled flights as the size-like parameter, we show that the relationships between the average communication activity and its standard deviation in both datasets can be well described by Taylor's power law, with scaling exponent α ≈ 0.77 ± 0.01 for the real operational data and α ≈ 0.54 ± 0.01 for the real-time training data. The difference between the exponents suggests that human dynamics under pressure is more likely dominated by the exogenous force. Our findings may lead to further understanding of human behavior.

  6. Virtualized Traffic at Metropolitan Scales

    Directory of Open Access Journals (Sweden)

    David eWilkie

    2015-05-01

    Full Text Available Few phenomena are more ubiquitous than traffic, and few are more significant economically, socially, or environmentally. Any virtual reality system, including virtual globes and immersive multi-player worlds that are set in a modern or futuristic setting feature traffic systems. Virtual reality models can also aid in addressing the challenges of real-world traffic systems, the ever-present gridlock and congestion in cities worldwide: traffic engineers and planners can diagnose system instabilities and explore control strategies in virtual worlds reconstructed from available sensor data. To create these systems, road network models need to be created and represented. Traffic needs to be realistically and efficiently simulated. To analyze real-world scenarios, the traffic conditions need to be estimated and reconstructed. To create virtual scenarios, such as simulated cities, traffic needs to be intelligently and efficiently routed.

  7. Research on Congestion Pricing in Multimode Traffic considering Delay and Emission

    Directory of Open Access Journals (Sweden)

    Hongna Dai

    2015-01-01

    Full Text Available Rapid development of urbanization and automation has resulted in serious urban traffic congestion and air pollution problems in many Chinese cities recently. As a traffic demand management strategy, congestion pricing is acknowledged to be effective in alleviating the traffic congestion and improving the efficiency of traffic system. This paper proposes an urban traffic congestion pricing model based on the consideration of transportation network efficiency and environment effects. First, the congestion pricing problem under multimode (i.e., car mode and bus mode urban traffic network condition is investigated. Second, a traffic congestion pricing model based on bilevel programming is formulated for a dual-mode urban transportation network, in which the delay and emission of vehicles are considered. Third, an improved mathematical algorithm combining successive average method with the genetic algorithm is proposed to solve the bilevel programming problem. Finally, a numerical experiment based on a hypothetical network is performed to validate the proposed congestion pricing model and algorithm.

  8. Urban expressway traffic state forecasting based on multimode maximum entropy model

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The accurate and timely traffic state prediction has become increasingly important for the traffic participants,especially for the traffic managements. In this paper,the traffic state is described by Micro-LOS,and a direct prediction method is introduced. The development of the proposed method is based on Maximum Entropy (ME) models trained for multiple modes. In the Multimode Maximum Entropy (MME) framework,the different features like temporal and spatial features of traffic systems,regional traffic state are integrated simultaneously,and the different state behaviors based on 14 traffic modes defined by average speed according to the date-time division are also dealt with. The experiments based on the real data in Beijing expressway prove that the MME models outperforms the already existing model in both effectiveness and robustness.

  9. Environmental problems of vibrations induced by railway traffic

    Institute of Scientific and Technical Information of China (English)

    XIA He; CAO Yanmei; De Roeck Guido; Degrande Geert

    2007-01-01

    In this paper, a general review is made on the problems of vibrations of the ground and nearby buildings induced by railway traffic, and on the researches on this sub- ject in theoretical analyses, numerical simulations, and field experiments. The characteristics of ground vibrations induced by railway traffic and their propagation, from the aspects of duration, intensity distribution, vehicle load and speed, are summarized. The vibration influences on the daily life of people, the operation of high-tech devices and the safety of buildings, and the vibration properties of subsoil and buildings adjacent to the underground, ground and elevated railway systems are introduced.

  10. Modeling traffic on crossroads

    Science.gov (United States)

    Wastavino, L. A.; Toledo, B. A.; Rogan, J.; Zarama, R.; Muñoz, V.; Valdivia, J. A.

    2007-07-01

    A simplified traffic model is studied, consisting of two vehicles traveling through a sequence of crossroads regulated by yield signs. A car approaching a yield sign stops if, in the other street, there is a car closer than a certain distance xtol from the intersection. It is shown that the function which maps the state of the vehicles displays a period doubling transition to chaos. An interesting feature of the dynamics is that for extremely cautious drivers ( xtol too large), the map turns chaotic, thus becoming a potential source of emergent jams. Complex behavior such as the one observed in this simple system seems to be an essential ingredient in traffic patterns, and could be of relevance in studying actual crossroads situations.

  11. Road Traffic Noise

    Science.gov (United States)

    Beckenbauer, Thomas

    Road traffic is the most interfering noise source in developed countries. According to a publication of the European Union (EU) at the end of the twentieth century [1], about 40% of the population in 15 EU member states is exposed to road traffic noise at mean levels exceeding 55 dB(A). Nearly 80 million people, 20% of the population, are exposed to levels exceeding 65 dB(A) during daytime and more than 30% of the population is exposed to levels exceeding 55 dB(A) during night time. Such high noise levels cause health risks and social disorders (aggressiveness, protest, and helplessness), interference of communication and disturbance of sleep; the long- and short-term consequences cause adverse cardiovascular effects, detrimental hormonal responses (stress hormones), and possible disturbance of the human metabolism (nutrition) and the immune system. Even performance at work and school could be impaired.

  12. Dementia and Traffic Accidents

    DEFF Research Database (Denmark)

    Petersen, Jindong Ding; Siersma, Volkert; Nielsen, Connie Thurøe;

    2016-01-01

    BACKGROUND: As a consequence of a rapid growth of an ageing population, more people with dementia are expected on the roads. Little is known about whether these people are at increased risk of road traffic-related accidents. OBJECTIVE: Our study aims to investigate the risk of road traffic......-related accidents for people aged 65 years or older with a diagnosis of dementia in Denmark. METHODS: We will conduct a nationwide population-based cohort study consisting of Danish people aged 65 or older living in Denmark as of January 1, 2008. The cohort is followed for 7 years (2008-2014). Individual's personal...... data are available in Danish registers and can be linked using a unique personal identification number. A person is identified with dementia if the person meets at least one of the following criteria: (1) a diagnosis of the disease in the Danish National Patient Register or in the Danish Psychiatric...

  13. An extended car-following model accounting for the average headway effect in intelligent transportation system

    Science.gov (United States)

    Kuang, Hua; Xu, Zhi-Peng; Li, Xing-Li; Lo, Siu-Ming

    2017-04-01

    In this paper, an extended car-following model is proposed to simulate traffic flow by considering average headway of preceding vehicles group in intelligent transportation systems environment. The stability condition of this model is obtained by using the linear stability analysis. The phase diagram can be divided into three regions classified as the stable, the metastable and the unstable ones. The theoretical result shows that the average headway plays an important role in improving the stabilization of traffic system. The mKdV equation near the critical point is derived to describe the evolution properties of traffic density waves by applying the reductive perturbation method. Furthermore, through the simulation of space-time evolution of the vehicle headway, it is shown that the traffic jam can be suppressed efficiently with taking into account the average headway effect, and the analytical result is consistent with the simulation one.

  14. Task Analysis Assessment on Intrastate Bus Traffic Controllers

    Science.gov (United States)

    Yen Bin, Teo; Azlis-Sani, Jalil; Nur Annuar Mohd Yunos, Muhammad; Ismail, S. M. Sabri S. M.; Tajedi, Noor Aqilah Ahmad

    2016-11-01

    Public transportation acts as social mobility and caters the daily needs of the society for passengers to travel from one place to another. This is true for a country like Malaysia where international trade has been growing significantly over the past few decades. Task analysis assessment was conducted with the consideration of cognitive ergonomic view towards problem related to human factors. Conducting research regarding the task analysis on bus traffic controllers had allowed a better understanding regarding the nature of work and the overall monitoring activities of the bus services. This paper served to study the task analysis assessment on intrastate bus traffic controllers and the objectives of this study include to conduct task analysis assessment on the bus traffic controllers. Task analysis assessment for the bus traffic controllers was developed via Hierarchical Task Analysis (HTA). There are a total of five subsidiary tasks on level one and only two were able to be further broken down in level two. Development of HTA allowed a better understanding regarding the work and this could further ease the evaluation of the tasks conducted by the bus traffic controllers. Thus, human error could be reduced for the safety of all passengers and increase the overall efficiency of the system. Besides, it could assist in improving the operation of the bus traffic controllers by modelling or synthesizing the existing tasks if necessary.

  15. Analysis of Traffic Capacity on Mountainous Two Lane Highway Adding Climbing Lane

    Directory of Open Access Journals (Sweden)

    Meng Yunwei

    2016-01-01

    Full Text Available During the construction of mountainous double lane highway, climbing lane plays a certain role for enhancing the traffic capacity. In order to explore traffic capacity improvement effect for different conditions of climbing lane, 20 representative models are chosen, which contain various combinations of alignment and traffic parameters. The changes of traffic capacity, average speed, delays, and saturation in models are obtained before and after the use of a climbing lane by means of numerical simulation. The results show that the use of a climbing lane could improve traffic capacity, average speed, while reducing delays and saturation. The improvement effect is different according to different combinations of alignment and traffic parameters. The research could provide a reference for mountainous climbing lane construction intend.

  16. Untieing the Traffic Knot

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Beijing is working to resolve its longtime transportation problems before the 2008 Olympics One traffic jam after another, annoying horns, endless lines of cars,impatient sighs from passengers on an overcrowded bus, the youstomped-on-my-toe quarreling in the subway train, all have led to the unsurprising result that Beijing scored at the tail end of a survey of 287 cities in the category of transport satisfaction in China’s 2006 Report on the Quality of Urban Life.

  17. Toothbrushing: Do It Daily.

    Science.gov (United States)

    Texas Child Care, 1993

    1993-01-01

    Offers a practical guide for promoting daily toothbrushing in young children. Discusses the importance of proper dental care, explains the causes of tooth decay, describes proper dental care for infants and young children, recommends materials and teaching methods, and discusses visits to the dentist and the benefits of fluoride for dental health.…

  18. The Physics of Traffic

    Science.gov (United States)

    Davis, L. Craig

    2006-03-01

    Congestion in freeway traffic is an example of self-organization in the language of complexity theory. Nonequilibrium, first-order phase transitions from free flow cause complex spatiotemporal patterns. Two distinct phases of congestion are observed in empirical traffic data--wide moving jams and synchronous flow. Wide moving jams are characterized by stopped or slowly moving vehicles within the jammed region, which widens and moves upstream at 15-20 km/h. Above a critical density of vehicles, a sudden decrease in the velocity of a lead vehicle can initiate a transition from metastable states to this phase. Human behaviors, especially delayed reactions, are implicated in the formation of jams. The synchronous flow phase results from a bottleneck such as an on-ramp. Thus, in contrast to a jam, the downstream front is pinned at a fixed location. The name of the phase comes from the equilibration (or synchronization) of speed and flow rate across all lanes caused by frequent vehicle lane changes. Synchronous flow occurs when the mainline flow and the rate of merging from an on-ramp are sufficiently large. Large-scale simulations using car-following models reproduce the physical phenomena occurring in traffic and suggest methods to improve flow and mediate congestion.

  19. Effects of traffic noise

    Energy Technology Data Exchange (ETDEWEB)

    Gottlob, D.

    1986-02-01

    One of the main sources of noise is road traffic. In 1984 there were over 25 million cars, 1.2 million lorries, 1.3 million motor cycles and 1.6 million mopeds using our roads. Opinion polls showed that 21% of the population felt that they were affected by traffic noise as a nuisance factor. An outline of the effects of this noise on the affected population is given, illustrated by diagrams. Details about noise emissions (drive-past level) of the different types of vehicles in city traffic are stated and the effects of noise described. The author goes into the nuisance effect (noise is not a physical factor, but a psychosocial one), changes in behaviour (ways of speaking, reduction of stress on households in proportion to rising income and higher educational levels) and the consequences for health (the reaction of the body to noise is primarily a consequence of the psychosomatic organisation of ow bodies). In conclusion, the author deals with the subjective efficiency of noise protection measures. (HWJ).

  20. Assessing Road Traffic Expression

    Directory of Open Access Journals (Sweden)

    Fábio Silva

    2014-12-01

    Full Text Available Road traffic is a problem which is increasing in cities with large population. Unrelated to this fact the number of portable and wearable devices has also been increasing throughout the population of most countries. With this advent, the capacity to monitor and register data about people habits and locations as well as more complex data such as intensity and strength of movements has created an opportunity to contribute to the general wealth and comfort within these environments. Ambient Intelligence and Intelligent Decision Making processes can benefit from the knowledge gathered by these devices to improve decisions on everyday tasks such as deciding navigation routes by car, bicycle or other means of transportation and avoiding route perils. The concept of computational sustainability may also be applied to this problem. Current applications in this area demonstrate the usefulness of real time system that inform the user of certain conditions in the surrounding area. On the other hand, the approach presented in this work aims to describe models and approaches to automatically identify current states of traffic inside cities and use methods from computer science to improve overall comfort and the sustainability of road traffic both with the user and the environment in mind. Such objective is delivered by analyzing real time contributions from those mobile ubiquitous devices to identifying problematic situations and areas under a defined criteria that have significant influence towards a sustainable use of the road transport infrastructure.

  1. Detecting Botnet Activities Based on Abnormal DNS traffic

    Directory of Open Access Journals (Sweden)

    Ahmed M. Manasrah

    2009-10-01

    Full Text Available The botnet is considered as a critical issue of the Internet due to its fast growing mechanism and affect. Recently, Botnets have utilized the DNS and query DNS server just like any legitimate hosts. In this case, it is difficult to distinguish between the legitimate DNS traffic and illegitimate DNS traffic. It is important to build a suitable solution for botnet detection in the DNS traffic and consequently protect the network from the malicious Botnets activities. In this paper, a simple mechanism is proposed to monitors the DNS traffic and detects the abnormal DNS traffic issued by the botnet based on the fact that botnets appear as a group of hosts periodically. The proposed mechanism is also able to classify the DNS traffic requested by group of hosts (group behavior and single hosts (individual behavior, consequently detect the abnormal domain name issued by the malicious Botnets. Finally, the experimental results proved that the proposed mechanism is robust and able to classify DNS traffic, and efficiently detects the botnet activity with average detection rate of 89%.

  2. Impacts of Snowy Weather Conditions on Expressway Traffic Flow Characteristics

    Directory of Open Access Journals (Sweden)

    Jiancheng Weng

    2013-01-01

    Full Text Available Snowy weather will significantly degrade expressway operations, reduce service levels, and increase driving difficulty. Furthermore, the impact of snow varies in different types of roads, diverse cities, and snow densities due to different driving behavior. Traffic flow parameters are essential to decide what should be appropriate for weather-related traffic management and control strategies. This paper takes Beijing as a case study and analyzes traffic flow data collected by detectors in expressways. By comparing the performance of traffic flow under normal and snowy weather conditions, this paper quantitatively describes the impact of adverse weather on expressway volume and average speeds. Results indicate that average speeds on the Beijing expressway under heavy snow conditions decrease by 10–20 km/h when compared to those under normal weather conditions, the vehicle headway generally increases by 2–4 seconds, and the road capacity drops by about 33%. This paper also develops a specific expressway traffic parameter reduction model which proposes reduction coefficients of expressway volumes and speeds under various snow density conditions in Beijing. The conclusions paper provide effective foundational parameters for urban expressway controls and traffic management under snow conditions.

  3. Agent Reward Shaping for Alleviating Traffic Congestion

    Science.gov (United States)

    Tumer, Kagan; Agogino, Adrian

    2006-01-01

    Traffic congestion problems provide a unique environment to study how multi-agent systems promote desired system level behavior. What is particularly interesting in this class of problems is that no individual action is intrinsically "bad" for the system but that combinations of actions among agents lead to undesirable outcomes, As a consequence, agents need to learn how to coordinate their actions with those of other agents, rather than learn a particular set of "good" actions. This problem is ubiquitous in various traffic problems, including selecting departure times for commuters, routes for airlines, and paths for data routers. In this paper we present a multi-agent approach to two traffic problems, where far each driver, an agent selects the most suitable action using reinforcement learning. The agent rewards are based on concepts from collectives and aim to provide the agents with rewards that are both easy to learn and that if learned, lead to good system level behavior. In the first problem, we study how agents learn the best departure times of drivers in a daily commuting environment and how following those departure times alleviates congestion. In the second problem, we study how agents learn to select desirable routes to improve traffic flow and minimize delays for. all drivers.. In both sets of experiments,. agents using collective-based rewards produced near optimal performance (93-96% of optimal) whereas agents using system rewards (63-68%) barely outperformed random action selection (62-64%) and agents using local rewards (48-72%) performed worse than random in some instances.

  4. CQ Switch Analysis under Traffic Overload

    Directory of Open Access Journals (Sweden)

    I. Maljević

    2011-06-01

    Full Text Available An analysis of 2x2 crossbar packet switch with buffers at crosspoints and round robin scheduling algorithm is presented in this paper. The analysis is performed for a non-admissible traffic pattern, where output ports are overloaded. The case of full offered load is observed and output ports are loaded with packets that have different arrival probabilities. In addition to the parameters that are commonly observed in such an analysis (throughput and average packet delay, memory requirements for the implementation of the buffer, as well as fair representation when servicing the buffer - the so-called fairness are also analyzed. The results show that even for a switch with a small number of ports very large buffers should be implemented, if we want to achieve satisfactory performance under traffic overload.

  5. Video Traffic Prediction Using Neural Networks

    Directory of Open Access Journals (Sweden)

    Miloš Oravec

    2008-10-01

    Full Text Available In this paper, we consider video stream prediction for application in services likevideo-on-demand, videoconferencing, video broadcasting, etc. The aim is to predict thevideo stream for an efficient bandwidth allocation of the video signal. Efficient predictionof traffic generated by multimedia sources is an important part of traffic and congestioncontrol procedures at the network edges. As a tool for the prediction, we use neuralnetworks – multilayer perceptron (MLP, radial basis function networks (RBF networksand backpropagation through time (BPTT neural networks. At first, we briefly introducetheoretical background of neural networks, the prediction methods and the differencebetween them. We propose also video time-series processing using moving averages.Simulation results for each type of neural network together with final comparisons arepresented. For comparison purposes, also conventional (non-neural prediction isincluded. The purpose of our work is to construct suitable neural networks for variable bitrate video prediction and evaluate them. We use video traces from [1].

  6. Phosphorus balance with daily dialysis.

    Science.gov (United States)

    Kooienga, Laura

    2007-01-01

    Hyperphosphatemia is an almost universal finding in patients with end-stage renal disease and is associated with increased all-cause mortality, cardiovascular mortality, and vascular calcification. These associations have raised the question of whether reducing phosphorus levels could result in improved survival. In light of the recent findings that increased per-session dialysis dose, as assessed by urea kinetics, did not result in improved survival, the definition of adequacy of dialysis should be re-evaluated and consideration given to alternative markers. Two alternatives to conventional thrice weekly dialysis (CHD) are nocturnal hemodialysis (NHD) and short daily hemodialysis (SDHD). The elimination kinetics of phosphorus as they relate to these alternative daily dialysis schedules and the clinical implications of overall phosphorus balance are discussed here. The total weekly phosphorus removal with NHD is more than twice that removed by CHD (4985 mg/week +/- 1827 mg vs. 2347 mg/week +/- 697 mg) and this is associated with a significantly lower average serum phosphorous (4.0 mg/dl vs. 6.5 mg/dl). In spite of the observed increase in protein and phosphorus intake seen in patients on SDHD, phosphate binder requirements and serum phosphorus levels are generally stable to decrease although this effect is strongly dependent on the frequency and overall treatment time.

  7. Traffic Prediction Based on Correlation of Road Sections

    Directory of Open Access Journals (Sweden)

    Xiaodan Huang

    2013-10-01

    Full Text Available Road section data packet is very necessary for the estimation and prediction in short-time traffic condition. However, previous researches on this problem are lack of quantitative analysis. A section correlation analyzing method with traffic flow microwave data is proposed for this problem. It is based on the metric multidimensional scaling theory. With a dissimilarity matrix, scalar product matrix can be calculated. Subsequently, a reconstructing matrix of section traffic flow could be got with principal components factor analysis, which could display section groups in low dimension. It is verified that the new method is reliable and effective. After that, Auto Regressive Moving Average (A RMA model is used for forecasting traffic flow and lane occupancy. Finally, a simulated example has shown that the technique is effective and exact. The theoretical analysis indicates that the forecasting model and algorithms have a broad prospect for practical application.  

  8. Real time traffic models, decision support for traffic management

    OpenAIRE

    Wismans, L.; De Romph, E.; Friso, K.; Zantema, K.

    2014-01-01

    Reliable and accurate short-term traffic state prediction can improve the performance of real-time traffic management systems significantly. Using this short-time prediction based on current measurements delivered by advanced surveillance systems will support decision-making processes on various control strategies and enhance the performance of the overall network. By taking proactive action deploying traffic management measures, congestion may be prevented or its effects limited. An approach...

  9. Modeling the effect of microscopic driving behaviors on Kerner's time-delayed traffic breakdown at traffic signal using cellular automata

    Science.gov (United States)

    Wang, Yang; Chen, Yan-Yan

    2016-12-01

    The signalized traffic is considerably complex due to the fact that various driving behaviors have emerged to respond to traffic signals. However, the existing cellular automaton models take the signal-vehicle interactions into account inadequately, resulting in a potential risk that vehicular traffic flow dynamics may not be completely explored. To remedy this defect, this paper proposes a more realistic cellular automaton model by incorporating a number of the driving behaviors typically observed when the vehicles are approaching a traffic light. In particular, the anticipatory behavior proposed in this paper is realized with a perception factor designed by considering the vehicle speed implicitly and the gap to its preceding vehicle explicitly. Numerical simulations have been performed based on a signal controlled road which is partitioned into three sections according to the different reactions of drivers. The effects of microscopic driving behaviors on Kerner's time-delayed traffic breakdown at signal (Kerner 2011, 2013) have been investigated with the assistance of spatiotemporal pattern and trajectory analysis. Furthermore, the contributions of the driving behaviors on the traffic breakdown have been statistically examined. Finally, with the activation of the anticipatory behavior, the influences of the other driving behaviors on the formation of platoon have been investigated in terms of the number of platoons, the averaged platoon size, and the averaged flow rate.

  10. Traffic Games: Modeling Freeway Traffic with Game Theory.

    Science.gov (United States)

    Cortés-Berrueco, Luis E; Gershenson, Carlos; Stephens, Christopher R

    2016-01-01

    We apply game theory to a vehicular traffic model to study the effect of driver strategies on traffic flow. The resulting model inherits the realistic dynamics achieved by a two-lane traffic model and aims to incorporate phenomena caused by driver-driver interactions. To achieve this goal, a game-theoretic description of driver interaction was developed. This game-theoretic formalization allows one to model different lane-changing behaviors and to keep track of mobility performance. We simulate the evolution of cooperation, traffic flow, and mobility performance for different modeled behaviors. The analysis of these results indicates a mobility optimization process achieved by drivers' interactions.

  11. Traffic Games: Modeling Freeway Traffic with Game Theory

    Science.gov (United States)

    Cortés-Berrueco, Luis E.; Gershenson, Carlos; Stephens, Christopher R.

    2016-01-01

    We apply game theory to a vehicular traffic model to study the effect of driver strategies on traffic flow. The resulting model inherits the realistic dynamics achieved by a two-lane traffic model and aims to incorporate phenomena caused by driver-driver interactions. To achieve this goal, a game-theoretic description of driver interaction was developed. This game-theoretic formalization allows one to model different lane-changing behaviors and to keep track of mobility performance. We simulate the evolution of cooperation, traffic flow, and mobility performance for different modeled behaviors. The analysis of these results indicates a mobility optimization process achieved by drivers’ interactions. PMID:27855176

  12. Making Daily Mobility

    DEFF Research Database (Denmark)

    Jensen, Ole B.; Wind, Simon

    , social networks, understanding of places and ultimately ourselves and others. To successfully accomplish everyday life, households have to cope with large number of different activities and mobility in relation to their children, work, social life, obligations, expectations, needs and wishes. Drawing...... practice configurations. The paper draws on empirical material collected from the project ‘Analysis of activity-based travel chains and sustainable mobility’ (ACTUM WP2), consisting of qualitative semi-structured interviews with 45 respondents in 11 children families spread across the Greater Copenhagen...... accomplishing daily life. The study also shows that practices need constant maintenance as they are continuously de-stabilised by changing conditions and situations. This careful and competent work involved in the maintenance and adjustment of daily practices is done in relation to the household member...

  13. Framework for Traffic Congestion Management

    OpenAIRE

    Mahmud Hassan TALUKDAR

    2013-01-01

    Traffic Congestion is one of many serious global problems in all great cities resulted from rapid urbanization which always exert negative externalities upon society. The solution of traffic congestion is highly geocentric and due to its heterogeneous nature, curbing congestion is one of the hard tasks for transport planners. It is not possible to suggest unique traffic congestion management framework which could be absolutely applied for every great cities. Conversely, it is quite feasible t...

  14. Traffic forecasts ignoring induced demand

    DEFF Research Database (Denmark)

    Næss, Petter; Nicolaisen, Morten Skou; Strand, Arvid

    2012-01-01

    Although the phenomenon of induced traffic has been theorized for more than 60 years and is now widely accepted among transport researchers, the traffic-generating effects of road capacity expansion are still often neglected in transport modelling. Such omission can lead to serious bias in the as......Although the phenomenon of induced traffic has been theorized for more than 60 years and is now widely accepted among transport researchers, the traffic-generating effects of road capacity expansion are still often neglected in transport modelling. Such omission can lead to serious bias...

  15. Road traffic noise and stroke

    DEFF Research Database (Denmark)

    Sørensen, Mette; Hvidberg, Martin; Andersen, Zorana J

    2011-01-01

    Epidemiological studies suggest that long-term exposure to road traffic noise increases the risk of cardiovascular disorders. The aim of this study was to investigate the relation between exposure to road traffic noise and risk for stroke, which has not been studied before.......Epidemiological studies suggest that long-term exposure to road traffic noise increases the risk of cardiovascular disorders. The aim of this study was to investigate the relation between exposure to road traffic noise and risk for stroke, which has not been studied before....

  16. Road traffic injuries

    Institute of Scientific and Technical Information of China (English)

    WANG Zheng-guo 王正国

    2003-01-01

    @@ The appearance of cars has raised materialistic civilization and living standard to an unprecedented level. Today, it is hard to imagine how we human beings can live without cars.Yet, motor vehicles can cause a great number of deaths and injuries as well as considerable economic losses, which have constituted the global burden. Understanding of the occurrence and development of road traffic injuries will contribute to the prevention and control of crash and to the implementation of "everybody has the right to enjoy health" proposed by WHO.

  17. Inaccuracy in traffic forecasts

    DEFF Research Database (Denmark)

    Flyvbjerg, Bent; Holm, Mette K. Skamris; Buhl, Søren Ladegaard

    2006-01-01

    that forecasters generally do a poor job of estimating the demand for transportation infrastructure projects. The result is substantial downside financial and economic risk. Forecasts have not become more accurate over the 30-year period studied. If techniques and skills for arriving at accurate demand forecasts...... forecasting. Highly inaccurate traffic forecasts combined with large standard deviations translate into large financial and economic risks. But such risks are typically ignored or downplayed by planners and decision-makers, to the detriment of social and economic welfare. The paper presents the data...

  18. An improved car-following model with two preceding cars' average speed

    Science.gov (United States)

    Yu, Shao-Wei; Shi, Zhong-Ke

    2015-01-01

    To better describe cooperative car-following behaviors under intelligent transportation circumstances and increase roadway traffic mobility, the data of three successive following cars at a signalized intersection of Jinan in China were obtained and employed to explore the linkage between two preceding cars' average speed and car-following behaviors. The results indicate that two preceding cars' average velocity has significant effects on the following car's motion. Then an improved car-following model considering two preceding cars' average velocity was proposed and calibrated based on full velocity difference model and some numerical simulations were carried out to study how two preceding cars' average speed affected the starting process and the traffic flow evolution process with an initial small disturbance, the results indicate that the improved car-following model can qualitatively describe the impacts of two preceding cars' average velocity on traffic flow and that taking two preceding cars' average velocity into account in designing the control strategy for the cooperative adaptive cruise control system can improve the stability of traffic flow, suppress the appearance of traffic jams and increase the capacity of signalized intersections.

  19. Tendências genética e fenotípica para ganho de peso médio diário entre a desmama e o sobreano em uma população Angus x Nelore Genetic and phenotypic trends for average daily weight gain from weaning to 550 days of age in a Angus Nellore population

    Directory of Open Access Journals (Sweden)

    D. D'avila Balbé

    2007-02-01

    Full Text Available Foram analisados os registros de ganho médio diário entre a desmama e o sobreano (GMDDS de 33.267 animais de uma população multirracial Angus - Nelore, filhos de 525 touros, criados em 37 rebanhos, em diversas regiões do Brasil, entre os anos de 1987 e 2001. O modelo animal usado incluiu os efeitos aleatórios genético aditivo direto e materno e residual e os efeitos fixos de grupo genético do pai, da mãe e do animal e do grupo de contemporâneos pós-desmama, além da covariável idade à desmama, não ajustada. O GMDDS médio observado para a população foi 384,22g. O ano de 1999 foi o que apresentou o maior GMDDS (484,04g, e o ano de 1992, o menor (299,42g. Os coeficientes de herdabilidade estimados foram: 0,30±0,11 (direta e 0,29±0,07 (materna. O VG médio foi de -0,827g. A tendência genética estimada para essa característica foi de -0,029g/ano (PDirect and maternal heritability coefficients were estimated and genetic and phenotypic trends were predicted for average weight gain from weaning to 550 days of age (AWG from 33,267 animals of a multi-breed Angus-Nellore population, sired by 525 bulls and raised in 37 herds in several regions of Brazil, from 1987 to 2001. MTDFREML was used for estimating the (covariance components utilized to estimate the genetic direct and maternal heritability coefficients and to predict the breeding values. The animal model included as fixed the genetic group of sire, dam and animal and the pos weaning year/station/herd contemporary group and the covariate weaning age, and as ramdom, the additive genetic, maternal and residual effects. The observed AWG was 384.22g, 1999 presented the highest (484.04g and 1992 the lowest value (299.42g. The direct heritability was 0.30±0.11, the maternal h² was 0.29±0.07 and the average genetic value was -0.827g. The estimated genetic trend for AWG was -0.029g (P<0.08 and the phenotypic trend was 5.68g (P<0.05. A phenotypic progress for average weight gain from

  20. Real time traffic models, decision support for traffic management

    NARCIS (Netherlands)

    Wismans, L.J.J.; Romph, de E.; Friso, K.; Zantema, K.

    2014-01-01

    Reliable and accurate short-term traffic state prediction can improve the performance of real-time traffic management systems significantly. Using this short-time prediction based on current measurements delivered by advanced surveillance systems will support decision-making processes on various con

  1. Real Time Traffic Models, Decision Support for Traffic Management

    NARCIS (Netherlands)

    Wismans, L.; De Romph, E.; Friso, K.; Zantema, K.

    2014-01-01

    Reliable and accurate short-term traffic state prediction can improve the performance of real-time traffic management systems significantly. Using this short-time prediction based on current measurements delivered by advanced surveillance systems will support decision-making processes on various con

  2. Traffic Infrastructure in the Development of the Croatian Traffic System

    Directory of Open Access Journals (Sweden)

    Damir Šimulčik

    2012-10-01

    Full Text Available The absence of a long-term traffic policy and of the policyof financing the constntction and maintenance of traffic infrastructurefacilities, represents a synthesis of numerous unresolvedrelations whose negative effects are felt in the overalleconomic and traffic development and consequently theevaluation of national potentials in the field. Adverse aspectcaused by the lack of a clear and feasible policy of financing thetraffic infrastructure facilities, is also a result of not having definedan adequate traffic policy, programme and strategiccourses of development, nor financing models that would be inaccordance with the market and economy system.This indicates that it is necessary to determine a policy forfinancing the constntction and maintenance of traffic infrastntcture,which has to be based on scientific development,team work, availability of plans and programmes to scientistsand experts, determined methodology based on marketing andeconomic logic in defining the programme and strategic tasksand assignments so as to make them feasible.In the near future, intensive preparations for investments inthe overall traffic sysiem are necessary, especially regarding thetraffic infrastntcture facilities - the pivotal points in the processof evaluating the traffic in our national tenitory. Croatia needsto define clearly its strategy in constructing and maintaining thegeneral traffic infrastructure, appointing at the same time thosewho will carry out the given tasks.

  3. Simulation of Traffic on Intersection After Change of Traffic Priority

    Directory of Open Access Journals (Sweden)

    Vladislav KŘIVDA

    2011-06-01

    Full Text Available This paper deals with problem of capacity calculation of intersection after change of traffic priority and with simulation of traffic using simulation software PTV VISSIM. This paper was prepared with financial support for project FRVŠ č. 2206/2011/F1/d “Innovation of Learning of Subjects from the Design of Urban Roads and Intersections”.

  4. Physical Theories with Average Symmetry

    OpenAIRE

    Alamino, Roberto C.

    2013-01-01

    This Letter probes the existence of physical laws invariant only in average when subjected to some transformation. The concept of a symmetry transformation is broadened to include corruption by random noise and average symmetry is introduced by considering functions which are invariant only in average under these transformations. It is then shown that actions with average symmetry obey a modified version of Noether's Theorem with dissipative currents. The relation of this with possible violat...

  5. Average Convexity in Communication Situations

    NARCIS (Netherlands)

    Slikker, M.

    1998-01-01

    In this paper we study inheritance properties of average convexity in communication situations. We show that the underlying graph ensures that the graphrestricted game originating from an average convex game is average convex if and only if every subgraph associated with a component of the underlyin

  6. Development of Road Traffic Assignment and Assessment Sub-Model Applied in the Traffic Study ...

    Directory of Open Access Journals (Sweden)

    Dražen Topolnik

    2012-10-01

    Full Text Available The described sub-model is just one small segment of theTraffic Study of the City of Zagreb, in the development of whichnumerous foreign and national experts and institutions tookpart. After comprehensive collection and processing of inputdata, the traffic experts, using the software package "MVATRIPS" for the analysis and search for optimal solutions to theproblem of traffic system, provided the models of public urbantransit for the future.This paper describes the analysis and assessment of sub-models in road traffic assignment for the morning peak, afternoonpeak and average off-peak hours. The principles of assignmentprocedure have been described as well as the convergencetests. The following has been specified: the users categories,the public transit pre-load, and the passenger car unit(PC U. The key guideline in selecting the route is a generalisedformulation of costs presented in the paper. The procedures ofcalibration and the assessment of the finite model have alsobeen defined according to the screenline flows, link flows, andtravelling times. In the end, the summary is given of the basiccharacteristics of the finite travelling matrices.

  7. Simulation Study of a Traffic Light Assistant Based on Vehicle-Infrastructure Communication

    CERN Document Server

    Treiber, Martin

    2014-01-01

    Vehicle-infrastructure communication opens up new ways to improve traffic flow efficiency at signalized intersections. In this study, we assume that equipped vehicles can obtain information about switching times of relevant traffic lights in advance, and additionally counting data from upstream detectors. By means of simulation, we investigate, how equipped vehicles can make use of this information to improve traffic flow. Criteria include cycle-averaged capacity, driving comfort, fuel consumption, travel time, and the number of stops. Depending on the overall traffic demand and the penetration rate of equipped vehicles, we generally find several percent of improvement.

  8. GPM, GMI Level 3 Daily GPROF Profiling VV03B

    Data.gov (United States)

    National Aeronautics and Space Administration — 3GPROF products provide global gridded monthly/daily precipitation averages from multiple satellites that can be used for climate studies. The 3GPROF products are...

  9. GPM, GMI Level 3 Daily GPROF Profiling VV03C

    Data.gov (United States)

    National Aeronautics and Space Administration — 3GPROF products provide global gridded monthly/daily precipitation averages from multiple satellites that can be used for climate studies. The 3GPROF products are...

  10. GPM, GMI Level 3 Daily GPROF Profiling VV03A

    Data.gov (United States)

    National Aeronautics and Space Administration — 3GPROF products provide global gridded monthly/daily precipitation averages from multiple satellites that can be used for climate studies. The 3GPROF products are...

  11. U.S. Daily Climate Normals (1981-2010)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The U.S. Daily Climate Normals for 1981 to 2010 are 30-year averages of meteorological parameters for thousands of U.S. stations located across the 50 states, as...

  12. Traffic Performance Analysis of Manet Routing Protocol

    CERN Document Server

    Rajeswari, S; 10.5121/ijdps.2011.2306

    2011-01-01

    The primary objective of this research work is to study and investigate the performance measures of Gossip Routing protocol and Energy Efficient and Reliable Adaptive Gossip routing protocols. We use TCP and CBR based traffic models to analyze the performance of above mentioned protocols based on the parameters of Packet Delivery Ratio, Average End-to-End Delay and Throughput. We will investigate the effect of change in the simulation time and Number of nodes for the MANET routing protocols. For Simulation, we have used ns-2 simulator.

  13. Multimedia Traffic Routing in Multilayer WDM Networks

    CERN Document Server

    Amphawan, Angela; Hasan, Hassanuddin

    2012-01-01

    The advent of real-time multimedia services over the Internet has stimulated new technologies for expanding the information carrying capacity of optical network backbones. Multilayer wavelength division multiplexing (WDM) packet switching is an emerging technology for increasing the bandwidth of optical networks. Two algorithms for the routing of the multimedia traffic flows were applied: (i) Capacitated Shortest Path First (CSPF) routing, which minimizes the distance of each flow linking the given source and destination nodes and satisfying capacity constraints; and (ii) Flow Deviation Algorithm (FDA) routing, which minimizes the network?wide average packet delay.

  14. Sampling Based Average Classifier Fusion

    Directory of Open Access Journals (Sweden)

    Jian Hou

    2014-01-01

    fusion algorithms have been proposed in literature, average fusion is almost always selected as the baseline for comparison. Little is done on exploring the potential of average fusion and proposing a better baseline. In this paper we empirically investigate the behavior of soft labels and classifiers in average fusion. As a result, we find that; by proper sampling of soft labels and classifiers, the average fusion performance can be evidently improved. This result presents sampling based average fusion as a better baseline; that is, a newly proposed classifier fusion algorithm should at least perform better than this baseline in order to demonstrate its effectiveness.

  15. Smart Collection and Storage Method for Network Traffic Data

    Science.gov (United States)

    2014-09-01

    Smart Collection and Storage Method for Network Traffic Data Angela Horneman Nathan Dell September 2014 TECHNICAL REPORT CMU/SEI-2014-TR...3.2.4 Database Storage 14 4 Smart Collection and Storage 16 4.1 Methodology 16 4.2 Capture-Specific Considerations 16 4.2.1 Full Packet Capture...25 Figure 3: Example Total Daily Volume 34 Figure 4: Example Peak Value Plot for Total Volumes Shown in Figure 3 34 Figure 5: Smart Collection and

  16. ANALYSIS OF TRAFFIC CONDITIONS IN URBAN THOROUGHFARES

    OpenAIRE

    Kovalenko, L.; Urdzik, S.

    2006-01-01

    Results of experimental investigations into descriptions of traffic flows in urban thoroughfares have been considered. Dependencies between traffic speed, density and intensity for various traffic conditions have been offered.

  17. Improved road traffic emission inventories by adding mean speed distributions

    NARCIS (Netherlands)

    Smit, R.; Poelman, M.; Schrijver, J.

    2008-01-01

    Does consideration of average speed distributions on roads-as compared to single mean speed-lead to different results in emission modelling of large road networks? To address this question, a post-processing method is developed to predict mean speed distributions using available traffic data from a

  18. Probabilistic description of traffic flow

    Science.gov (United States)

    Mahnke, R.; Kaupužs, J.; Lubashevsky, I.

    2005-03-01

    A stochastic description of traffic flow, called probabilistic traffic flow theory, is developed. The general master equation is applied to relatively simple models to describe the formation and dissolution of traffic congestions. Our approach is mainly based on spatially homogeneous systems like periodically closed circular rings without on- and off-ramps. We consider a stochastic one-step process of growth or shrinkage of a car cluster (jam). As generalization we discuss the coexistence of several car clusters of different sizes. The basic problem is to find a physically motivated ansatz for the transition rates of the attachment and detachment of individual cars to a car cluster consistent with the empirical observations in real traffic. The emphasis is put on the analogy with first-order phase transitions and nucleation phenomena in physical systems like supersaturated vapour. The results are summarized in the flux-density relation, the so-called fundamental diagram of traffic flow, and compared with empirical data. Different regimes of traffic flow are discussed: free flow, congested mode as stop-and-go regime, and heavy viscous traffic. The traffic breakdown is studied based on the master equation as well as the Fokker-Planck approximation to calculate mean first passage times or escape rates. Generalizations are developed to allow for on-ramp effects. The calculated flux-density relation and characteristic breakdown times coincide with empirical data measured on highways. Finally, a brief summary of the stochastic cellular automata approach is given.

  19. Reports on internet traffic statistics

    NARCIS (Netherlands)

    Hoogesteger, Martijn; Oliveira Schmidt, de Ricardo; Sperotto, Anna; Pras, Aiko

    2013-01-01

    Internet traffic statistics can provide valuable information to network analysts and researchers about the way nowadays networks are used. In the past, such information was provided by Internet2 in a public website called Internet2 NetFlow: Weekly Reports. The website reported traffic statistics fro

  20. Traffic Light Controller Using Fpga

    Directory of Open Access Journals (Sweden)

    D.Bhavana

    2015-04-01

    Full Text Available The traffic light sequence works on the specific switching of Red, Green and Yellow lights in a particular way with stipulated time form. The normal function of traffic lights requires sophisticated control and coordination to ensure that traffic moves as smoothly and safely as possible and that pedestrians are protected when they cross the roads [1] .This Traffic Light sequence is generated using a specific switching mechanism which will help to control a traffic light system on a road in a specified sequence. This paper focuses on the fact that the traffic lights can be varied in the day and night mode depending on the intensity of the traffic. It plays a vital role in supervising and running the metropolitan traffic and evade the possibilities of any unfortunate mishaps happening in and around the cities. It is a sequential machine to be scrutinized as per the requirements and programmed through a multistep development process. The methods that are used in this project are proposing the circuit, write a code, simulate, synthesis and implement on the hardware [8] . In this project, XILINX Software was chosen to devise a schematic using schematic edit, write a code using Verilog HDL (Hardware Description Language text editor and implements the circuit on Programmable Logic Device [PLD].The system has been successfully tested and implemented in hardware using Nexys 2 Digilent FPGA.

  1. Metro manila transport and traffic management plan (1993-1998)

    Energy Technology Data Exchange (ETDEWEB)

    Cal, P.C.

    1995-12-31

    In 1988, former President Corazon Aquino created the Presidential Task Force on Traffic Management to formulate plans and programs to improve the traffic situation in Metro Manila and to address the emerging problem of air pollution and concern on renewable energy sources for transportation. The Task Force formulated the Metro Manila Traffic Improvement Plan (TRIP) which was approved by President Aquino for implementation. TRIP called for the development of a mass urban transport system, which included the expansion of the light rail transit system and the construction and improvement of the Metro Manila road network. Culled mainly from the TRIP proposals, the Updated Transport and Traffic Management Plan for Metro Manila (1993-1998) was developed through interagency discussions, public consultations, data collation and research work. This plan is directed towards the development of a more responsive public transport system, expansion of road network capacity, and improvement of traffic management and enforcement. Constraints may be present along the way but opportunities and potentials exist for the deliverance of daily commuters struggling to make a living.

  2. Demonstration of alternative traffic information collection and management technologies

    Science.gov (United States)

    Knee, Helmut E.; Smith, Cy; Black, George; Petrolino, Joe

    2004-03-01

    Many of the components associated with the deployment of Intelligent Transportation Systems (ITS) to support a traffic management center (TMC) such as remote control cameras, traffic speed detectors, and variable message signs, have been available for many years. Their deployment, however, has been expensive and applied primarily to freeways and interstates, and have been deployed principally in the major metropolitan areas in the US; not smaller cities. The Knoxville (Tennessee) Transportation Planning Organization is sponsoring a project that will test the integration of several technologies to estimate near-real time traffic information data and information that could eventually be used by travelers to make better and more informed decisions related to their travel needs. The uniqueness of this demonstration is that it will seek to predict traffic conditions based on cellular phone signals already being collected by cellular communications companies. Information about the average speed on various portions of local arterials and incident identification (incident location) will be collected and compared to similar data generated by "probe vehicles". Successful validation of the speed information generated from cell phone data will allow traffic data to be generated much more economically and utilize technologies that are minimally infrastructure invasive. Furthermore, when validated, traffic information could be provided to the traveling public allowing then to make better decisions about trips. More efficient trip planning and execution can reduce congestion and associated vehicle emissions. This paper will discuss the technologies, the demonstration project, the project details, and future directions.

  3. Web traffic and firm performance

    DEFF Research Database (Denmark)

    Farooq, Omar; Aguenaou, Samir

    2013-01-01

    into better firm performance? This paper aims to answer these questions by documenting a positive relationship between the extent of web-traffic and firm performance in the MENA region during the 2010. We argue that higher web-traffic lowers the agency problems in firms by disseminating more information...... to stock market participants. Consequently, lower agency problems translate into better performance. Furthermore, we also show that agency reducing role of web-traffic is more pronounced in regimes where information environment is already bad. For example, our results show stronger impact of web......-traffic on firm performance in civil law countries, firms with concentrated ownership, and firms with more intangible assets. All of these groups are characterized by higher agency problems. Our results, therefore, indicate that web-traffic can play a substitute for traditional governance mechanisms in the MENA...

  4. Comparative analysis of characteristics and risk fac-tors of traffic injury in aged people from urban and rural

    Directory of Open Access Journals (Sweden)

    ZHANG Liang

    2012-04-01

    Full Text Available 【Abstract】Objective: To study the epidemiologic characteristics of traffic injuries among people over 60 years old in the Nan’an district (urban and Jiangjin district (rural of Chongqing, and to discuss the corresponding strategies for its prevention and cure. Methods: Records of traffic injuries in people over 60 years old registered by the traffic police between 2000 and 2006 in Nan’an district and Jiangjin district were collected in the Database of Road Traffic Accidents and Traffic Injuries. Epidemiologic characteristics of traffic injuries among the aged people were analyzed and compared. Results: Between the year 2000 and 2006, the average annual incidence of traffic injuries and mortality rate in the aged people in Nan’an district were 124.62/100 000 and 13.85/ 100 000 respectively, higher than that in Jiangjin district (27.49/ 100 000, 7.13/100 000, P<0.01. However, the mortality rate for the aged people who were involved in traffic injuries in Jiangjin district was 20.60%, higher than that in Nan’an district (10.00%, P<0.01. Head injury was the primary cause of death. Totally 76.58% of casualties were pede-strians. Over 90% of the traffic accidents occurred in the areas with no traffic signal or traffic control system. Conclusions: The traffic environment is unfavorable to the aged people. It is important to enhance traffic safety consciousness of drivers and the elderly and to strengthen traffic safety system and traffic law, so as to provide a safe road traffic environment for the aged people. Key words: Aged; Epidemiology; Accidents, traffic; Risk factors

  5. A Method for Traffic Congestion Clustering Judgment Based on Grey Relational Analysis

    Directory of Open Access Journals (Sweden)

    Yingya Zhang

    2016-05-01

    Full Text Available Traffic congestion clustering judgment is a fundamental problem in the study of traffic jam warning. However, it is not satisfactory to judge traffic congestion degrees using only vehicle speed. In this paper, we collect traffic flow information with three properties (traffic flow velocity, traffic flow density and traffic volume of urban trunk roads, which is used to judge the traffic congestion degree. We first define a grey relational clustering model by leveraging grey relational analysis and rough set theory to mine relationships of multidimensional-attribute information. Then, we propose a grey relational membership degree rank clustering algorithm (GMRC to discriminant clustering priority and further analyze the urban traffic congestion degree. Our experimental results show that the average accuracy of the GMRC algorithm is 24.9% greater than that of the K-means algorithm and 30.8% greater than that of the Fuzzy C-Means (FCM algorithm. Furthermore, we find that our method can be more conducive to dynamic traffic warnings.

  6. Urban Traffic Control Using Adjusted Reinforcement Learning in a Multi-agent System

    Directory of Open Access Journals (Sweden)

    Mahshid Helali Moghadam

    2013-09-01

    Full Text Available Dynamism, continuous changes of states and the necessity to respond quickly are the specific characteristics of the environment in a traffic control system. Proposing an appropriate and flexible strategy to meet the existing requirements is always an important issue in traffic control. This study presents an adaptive approach to control urban traffic using multi-agent systems and a reinforcement learning augmented by an adjusting pre-learning stage. In this approach, the agent primarily uses some statistical traffic data and then uses traffic engineering theories for computing appropriate values of the traffic parameters. Having these primary values, the agents start the reinforcement learning based on the basic calculated information. The proposed approach, at first finds the approximate optimal zone for traffic parameters based on traffic engineering theories. Then using an appropriate reinforcement learning, it tries to exploit the best point according to different conditions. This approach was implemented on a network in traffic simulator software. The network was composed of six four phased intersections and 17 two lane streets. In the simulation, pedestrians were not considered in the system. The load of the network is defined in terms of Origin-Destination matrices whose entries represent the number of trips from an origin to a destination as a function of time. The simulation ran for five hours and an average traffic volume was used. According to the simulation results, the proposed approach behaved adaptively in different conditions and had better performance than the theory-based fixed-time control.

  7. Traffic information computing platform for big data

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Zongtao, E-mail: ztduan@chd.edu.cn; Li, Ying, E-mail: ztduan@chd.edu.cn; Zheng, Xibin, E-mail: ztduan@chd.edu.cn; Liu, Yan, E-mail: ztduan@chd.edu.cn; Dai, Jiting, E-mail: ztduan@chd.edu.cn; Kang, Jun, E-mail: ztduan@chd.edu.cn [Chang' an University School of Information Engineering, Xi' an, China and Shaanxi Engineering and Technical Research Center for Road and Traffic Detection, Xi' an (China)

    2014-10-06

    Big data environment create data conditions for improving the quality of traffic information service. The target of this article is to construct a traffic information computing platform for big data environment. Through in-depth analysis the connotation and technology characteristics of big data and traffic information service, a distributed traffic atomic information computing platform architecture is proposed. Under the big data environment, this type of traffic atomic information computing architecture helps to guarantee the traffic safety and efficient operation, more intelligent and personalized traffic information service can be used for the traffic information users.

  8. Scaling behaviour in daily air humidity fluctuations

    CERN Document Server

    Vattay, G; Vattay, Gabor; Harnos, Andrea

    1994-01-01

    We show that the daily average air humidity fluctuations exhibit non-trivial $1/f^{\\alpha}$ behaviour which different from the spectral properties of other meteorological quantities. This feature and the fractal spatial strucure found in clouds make it plausible to regard air humidity fluctuations as a manifestation of self-organized criticality. We give arguments why the dynamics in air humidity can be similar to those in sandpile models of SOC.

  9. New daily persistent headache

    Directory of Open Access Journals (Sweden)

    Alok Tyagi

    2012-01-01

    Full Text Available New daily persistent headache (NDPH is a chronic headache developing in a person who does not have a past history of headaches. The headache begins acutely and reaches its peak within 3 days. It is important to exclude secondary causes, particularly headaches due to alterations in cerebrospinal fluid (CSF pressure and volume. A significant proportion of NDPH sufferers may have intractable headaches that are refractory to treatment. The condition is best viewed as a syndrome rather than a diagnosis. The headache can mimic chronic migraine and chronic tension-type headache, and it is also important to exclude secondary causes, particularly headaches due to alterations in CSF pressure and volume. A large proportion of NDPH sufferers have migrainous features to their headache and should be managed with treatments used for treating migraine. A small group of NDPH sufferers may have intractable headaches that are refractory to treatment.

  10. Physics in daily life

    CERN Document Server

    Hermans, Jo

    2012-01-01

    This book provides answers to everyday questions that any curious mind would ask, like : Why is water blue ? What makes ice so slippery ? How do we localize sound ? How do we keep our body temperature so nice and constant ? How do we survive the sauna at 90 C ? Why do large raindrops fall faster than small ones, and what exactly is their speed ? The answers are given in an accessible and playful way, and are illustrated with funny cartoons. In this book forty "Physics in Daily Life" columns, which appeared earlier in Europhysics News, are brought together in one inspiring volume. As well as being a source of enjoyment and satisfying insights for anyone with some physics background, it also serves as a very good teaching tool for science students. This booklet is a feast of erudition and humour.

  11. Energy savings in dynamic and resilient optical networks based on traffic-aware strategies

    DEFF Research Database (Denmark)

    Turus, Ioan; Fagertun, Anna Manolova; Dittmann, Lars

    2014-01-01

    An analysis of the energy savingsis presentedwhen taking into account a complete traffic model for a one-yeartime period. Daily and weekly traffic fluctuations as well asyearly traffic growth are considered whenanalyzing the powerconsumption.Low power mode in optoelectronic devices (sleep...... andconnections. Results show that symbol-rateadaptation provides high savings for unprotected scenarios (37% energy savings w.r.t. unprotected Baseline), while for theprotected scenarios better results are obtained for modulationformat adaptation which includes sleep-mode (57.1% energysavings w.r.t. protected...

  12. Monthly Summaries of the Global Historical Climatology Network - Daily (GHCN-D)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Monthly Summaries of Global Historical Climatology Network (GHCN)-Daily is a dataset derived from GHCN-Daily. The data are produced by computing simple averages or...

  13. Nonlinear analysis of a new car-following model accounting for the global average optimal velocity difference

    Science.gov (United States)

    Peng, Guanghan; Lu, Weizhen; He, Hongdi

    2016-09-01

    In this paper, a new car-following model is proposed by considering the global average optimal velocity difference effect on the basis of the full velocity difference (FVD) model. We investigate the influence of the global average optimal velocity difference on the stability of traffic flow by making use of linear stability analysis. It indicates that the stable region will be enlarged by taking the global average optimal velocity difference effect into account. Subsequently, the mKdV equation near the critical point and its kink-antikink soliton solution, which can describe the traffic jam transition, is derived from nonlinear analysis. Furthermore, numerical simulations confirm that the effect of the global average optimal velocity difference can efficiently improve the stability of traffic flow, which show that our new consideration should be taken into account to suppress the traffic congestion for car-following theory.

  14. Statistical Multiplexing of Video Traffic and Data Traffic

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    This paper studies statistical multiplexing performance byinput of video traffic and data traffic. The inputs have different Qos requirements such as loss and delay jitter. By applying a modified FBM model, we present methods to estimate effective bandwidth of the aggregated traffic. Simulationswere paformed to evaluate effective bandwidth. The comparison between the estimation and the simulation shows that the estimations can give correct data for the effective bandwidths in terms of our interests. The analysis of gain by using priority multiplexing also addresses proper Qos configuration for the inputs in order to achieve positive gains.

  15. Physical Theories with Average Symmetry

    CERN Document Server

    Alamino, Roberto C

    2013-01-01

    This Letter probes the existence of physical laws invariant only in average when subjected to some transformation. The concept of a symmetry transformation is broadened to include corruption by random noise and average symmetry is introduced by considering functions which are invariant only in average under these transformations. It is then shown that actions with average symmetry obey a modified version of Noether's Theorem with dissipative currents. The relation of this with possible violations of physical symmetries, as for instance Lorentz invariance in some quantum gravity theories, is briefly commented.

  16. Vertical and horizontal variability in airborne nanoparticles and their exposure around signalised traffic intersections.

    Science.gov (United States)

    Goel, Anju; Kumar, Prashant

    2016-07-01

    We measured size-resolved PNCs in the 5-560 nm range at two different types (4- and 3-way) of TIs in Guildford (Surrey, UK) at fixed sites (∼1.5 m above the road level), sequentially at 4 different heights (1, 1.5, 2.5 and 4.7 m), and along the road at five different distances (10, 20, 30, 45 and 60 m). The aims were to: (i) assess the differences in PNCs measured at studied TIs, (ii) identify the best fit probability distribution curves for the PNCs, (iii) determine vertical and horizontal decay profiles of PNCs, (iv) estimate particle number emission factors (PNEFs) under congested and free-flow traffic conditions, and (v) quantify the pedestrian exposure in terms of respiratory deposition dose (RDD) rates at the TIs. Daily averaged particle number distributions at TIs reflected the effect of fresh emissions with peaks at 5.6, 10 and 56 nm. Despite the relatively high traffic volume at 3-way TI, average PNCs at 4-way TI were about twice as high as at 3-way TI, indicating less favourable dispersion conditions. Generalised extreme value distribution fitted well to PNC data at both TIs. Vertical PNC profiles followed an exponential decay, which was much sharper at 4-way TI than at 3-way TI, suggesting ∼40% less exposure for people at first floor (4.7 m) to those at ground floor around 4-way TI. Vertical profiles indicated much sharper (∼132-times larger) decay than in horizontal direction, due to close vicinity of road vehicles during the along-road measurements. Over an order of magnitude higher PNEFs were found during congested, compared with free-flow, conditions due to frequent changes in traffic speed. Average RDD rate at 4-way TI during congested conditions were up to 14-times higher than those at 3-way TI (0.4 × 10(11) h(-1)). Findings of this study are a step forward to understand exposure at and around the TIs.

  17. Framework for Traffic Congestion Management

    Directory of Open Access Journals (Sweden)

    Mahmud Hassan TALUKDAR

    2013-06-01

    Full Text Available Traffic Congestion is one of many serious global problems in all great cities resulted from rapid urbanization which always exert negative externalities upon society. The solution of traffic congestion is highly geocentric and due to its heterogeneous nature, curbing congestion is one of the hard tasks for transport planners. It is not possible to suggest unique traffic congestion management framework which could be absolutely applied for every great cities. Conversely, it is quite feasible to develop a framework which could be used with or without minor adjustment to deal with congestion problem. So, the main aim of this paper is to prepare a traffic congestion mitigation framework which will be useful for urban planners, transport planners, civil engineers, transport policy makers, congestion management researchers who are directly or indirectly involved or willing to involve in the task of traffic congestion management. Literature review is the main source of information of this study. In this paper, firstly, traffic congestion is defined on the theoretical point of view and then the causes of traffic congestion are briefly described. After describing the causes, common management measures, using world- wide, are described and framework for supply side and demand side congestion management measures are prepared.

  18. The Impact of Different Scheduling Policies on Traffic Class Dependent Routing in Intersatellite Link

    Science.gov (United States)

    Kandus, Gorazd; Svigelj, Ales; Mohorcic, Mihael

    2003-07-01

    In this paper we analyse the impact of different scheduling policies on traffic class dependent routing in intersatellite link network of a packet switched non-geostationary satellite system. We used different unfair (first come first served and priority) and fair (weighted round robin, deficit round robin and surplus round robin) scheduling mechanisms. Specifically developed software to model the ISL network was used to evaluate the performance of different combinations of scheduling and routing procedures. The analysis was done in terms of average packet delay and average data throughput for different traffic scenarios. The results imply that there is a small impact of different fair scheduling mechanisms on traffic class depending on routing.

  19. Quantized average consensus with delay

    NARCIS (Netherlands)

    Jafarian, Matin; De Persis, Claudio

    2012-01-01

    Average consensus problem is a special case of cooperative control in which the agents of the network asymptotically converge to the average state (i.e., position) of the network by transferring information via a communication topology. One of the issues of the large scale networks is the cost of co

  20. Road traffic fatalities in Qatar Jordan and UAE

    OpenAIRE

    Elawad, Elmogiera

    2016-01-01

    ABSTRACT Smeed’s equation is a widely used model for prediction of traffic fatalities but has been found inadequate for use in developing countries. We applied regression analysis to time-series data on vehicles, population and traffic fatalities in the United Arab Emirates (UAE), Jordan and Qatar. The data were fitted to exponential models for fatality prediction, producing an average absolute error of 20.9% for Qatar, 10.9% for Jordan and 5.5% for the UAE. We found a strong linear relations...

  1. Edificio Daily Mirror

    Directory of Open Access Journals (Sweden)

    Williams, Owen

    1963-07-01

    Full Text Available The building has 18 levels. The Press occupies the 4 basement floors. The ground floor is taken up with the entrance hall, and an indoor carriage way. A snack bar and the telephone operators are situated on the second floor. The production department and the medical services are located on the third storey, whilst the fourth is occupied by the offices and library. The fifth floor is the beginning of the higher section of the building. This floor and up to including the 11th floor are devoted to office space, except for the 10th storey, which contains the office apartments of the directors and the Council Chamber. Equipment related to various services of the building is housed on the 12th storey. Finally, this tall building constitutes a fine landmark in the London skyline. The Daily Mirror building is outstanding for the appropriate nature, the completeness and the quality of its installations, which thus provide the most widely read paper in the world with outstandingly efficient offices.Este edificio consta de 18 plantas. El cuerpo de Prensa se aloja en los cuatro sótanos; los vestíbulos de entrada y una calzada interior para vehículos se hallan en la planta baja; la primera alberga un snack-bar y centralita telefónica; la segunda, el departamento de producción y centro de asistencia médica, y la tercera, las oficinas y biblioteca principales. La cuarta planta señala el comienzo del bloque alto; esta planta, junto con las quinta, sexta, séptima, octava y décima, están dedicadas a oficinas. La novena contiene las oficinas-apartamentos de los directores y salas de Consejo, y la undécima, la maquinaria para las diversas instalaciones del edificio. La elevada torre constituye un grandioso hito de referencia en esta zona de Londres. El «Daily Mirror» se distingue por el acierto, número y perfección de sus instalaciones, que proporcionan, al periódico de mayor actualidad mundial, las más adecuadas y amplias oficinas modernas.

  2. Traffic jams: dynamics and control.

    Science.gov (United States)

    Orosz, Gábor; Wilson, R Eddie; Stépán, Gábor

    2010-10-13

    This introductory paper reviews the current state-of-the-art scientific methods used for modelling, analysing and controlling the dynamics of vehicular traffic. Possible mechanisms underlying traffic jam formation and propagation are presented from a dynamical viewpoint. Stable and unstable motions are described that may give the skeleton of traffic dynamics, and the effects of driver behaviour are emphasized in determining the emergent state in a vehicular system. At appropriate points, references are provided to the papers published in the corresponding Theme Issue.

  3. OPTIMASI BANDWITH MENGGUNAKAN TRAFFIC SHAPPING

    Directory of Open Access Journals (Sweden)

    Imam Riadi

    2012-05-01

    Full Text Available Perkembangan layanan komunikasi telah berkembang sangat pesat. Salah satunya adalah pemanfaatan penggunaan bandwith untuk mengakases jaringan Internet. Traffic shapping bandwidth dapat memberikan efesiensi dalam hal pemanfaatan bandwidth pada instansi yang melakukan manajemen dalam lalulintas jaringannya. Metode yang digunakan dalam penelitian ini adalah metode literatur yaitu metode pengumpulan data yang dilakukan dengan mengumpulkan sumber-sumber data yang terkait dan metode eksperimen yaitu melakukan penelitian dengan mengkonfigurasi Mikrotik RouterOS untuk melakukan traffic shapping bandwidth. Hasil penelitian ini adalah router yang dapat melakukan traffic shapping sehingga kualitas koneksi menjadi lebih baik untuk mengakses dan mengambil data dari sebuah website.

  4. 26 CFR 1.989(b)-1 - Definition of weighted average exchange rate.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 10 2010-04-01 2010-04-01 false Definition of weighted average exchange rate. 1... average exchange rate. For purposes of section 989(b)(3) and (4), the term “weighted average exchange rate” means the simple average of the daily exchange rates (determined by reference to a qualified source...

  5. [Comics for traffic education: evaluation of a traffic safety campaign].

    Science.gov (United States)

    Bonfadelli, H

    1989-01-01

    Traffic safety campaigns often are ineffective to change driving behavior because they don't reach the target group or are recognized only by people who are already interested or concerned. The evaluation of a traffic safety campaign called "Leo Lässig", addressed to young new drivers, shows that recognition and acceptance by the target group were stimulated by the age-conform means of comic-strips.

  6. Comparative analysis of characteristics and risk factors of traffic injury in aged people from urban and rural areas in Chongqing

    Institute of Scientific and Technical Information of China (English)

    ZHANG Liang; ZHOU Ji-hong; QIU Jun; ZHANG Xiu-zhu; YUAN Dan-feng; GAO Zhi-ming; DAI Wei

    2012-01-01

    Objective:To study the epidemiologic characteristics of traffic injuries among people over 60 years old in the Nan' an district(urban)and Jiangjin district(rural)of Chongqing,and to discuss the corresponding strategies for its prevention and cure.Methods:Records of traffic injuries in people over 60 years old registered by the traffic police between 2000 and 2006 in Nan'an district and Jiangjin district were collected in the Database of Road Traffic Accidents and Traffic Injuries.Epidemiologic characteristics of traffic injuries among the aged people were analyzed and compared.Results:Between the year 2000 and 2006,the average annual incidence of traffic injuries and mortality rate in the aged people in Nan' an district were 124.62/100 000 and 13.85/100 000 respectively,higher than that in Jiangjin district(27.49/100 000,7.13/100 000,P<0.01).However,the mortality rate for the aged people who were involved in traffic injuries in Jiangjin district was 20.60%,higher than that in Nan'an district(10.00%,P<0.01).Head injury was the primary cause of death.Totally 76.58% of casualties were pedestrians.Over 90% of the traffic accidents occurred in the areas with no traffic signal or traffic control system.Conclusions:The traffic environment is unfavorable to the aged people.It is important to enhance traffic safety consciousness of drivers and the elderly and to strengthen traffic safety system and traffic law,so as to provide a safe road traffic environment for the aged people.

  7. Characteristics of synchronized traffic in mixed traffic flow

    Institute of Scientific and Technical Information of China (English)

    Ning Hong-Xin; Xue Yu

    2012-01-01

    In this paper,the characteristics of synchronized traffic in mixed traffic flow are investigated based on the braking light model.By introducing the energy dissipation and the distribution of slowdown vehicles,the effects of the maximum velocity,the mixing ratio,and the length of vehicles on the synchronized flow are discussed.It is found that the maximum velocity plays a great role in the synchronized flow in mixed traffic.The energy dissipation and the distribution of slowdown vehicles in the synchronized flow region are greatly different from those in free flow and a traffic jamming region.When all of vehicles have the same maximum velocity with Vmax > 15,the mixed traffic significantly displays synchronized flow,which has been demonstrated by the relation between flow rate and occupancy and estimation of the cross-correlation function.Moreover,the energy dissipation in the synchronized flow region does not increase with occupancy.The distribution of slowdown vehicles shows a changeless platform in the synchronized flow region.This is an interesting phenomenon. It helps to deeply understand the synchronized flow and greatly reduce the energy dissipation of traffic flow.

  8. Assessment of commuters' daily exposure to flash flooding over the roads of the Gard region, France

    Science.gov (United States)

    Debionne, Samuel; Ruin, Isabelle; Shabou, Saif; Lutoff, Céline; Creutin, Jean-Dominique

    2016-10-01

    Flash floods are responsible for a majority of natural disaster fatalities in the USA and Europe and most of them are vehicle-related. If human exposure to flood is generally assessed through the number of inhabitants per buildings located in flood prone zone, it is clear that this number varies dramatically throughout the day as people move from place to place to follow their daily program of activities. Knowing the number of motorists exposed on flood prone road sections or the factors determining their exposure would allow providing a more realistic evaluation of the degree of exposure. In order to bridge this gap and provide emergency managers with methods to assess the risk level for motorists, this paper describes two methods, a simple rough-and-ready estimate and a traffic attribution method, and applies both of them on datasets of the Gard département, an administrative region of Southern France with about 700 000 inhabitants over 5875 km2. The first method to obtain an overall estimation of motorists flood exposure is to combine (i) the regional density of roads and rivers to derive a count of potential road cuts and (ii) the average daily kilometers driven by commuters of the study area to derive the number of people passing these potential cuts. If useful as a first approximation, this method fails to capture the spatial heterogeneities introduced by the geometry of river and road networks and the distribution of commuters' itineraries. To address this point, this paper (i) uses a pre-established detailed identification of road cuts (Naulin et al., 2013) and (ii) applies a well-known traffic attribution method to existing and freely available census datasets. Both methods indicate that commuters' exposure is much larger than the number of commuters itself, illustrating the risk amplification effect of mobility. Comparing the results from both methods shows that (i) the road network geometry plays a significant role in reducing the risk of river

  9. Gaussian moving averages and semimartingales

    DEFF Research Database (Denmark)

    Basse-O'Connor, Andreas

    2008-01-01

    In the present paper we study moving averages (also known as stochastic convolutions) driven by a Wiener process and with a deterministic kernel. Necessary and sufficient conditions on the kernel are provided for the moving average to be a semimartingale in its natural filtration. Our results...... are constructive - meaning that they provide a simple method to obtain kernels for which the moving average is a semimartingale or a Wiener process. Several examples are considered. In the last part of the paper we study general Gaussian processes with stationary increments. We provide necessary and sufficient...

  10. Traffic Flow Condition Classification for Short Sections Using Single Microwave Sensor

    Directory of Open Access Journals (Sweden)

    Memiş Kemal

    2010-01-01

    Full Text Available Daily observed traffic flow can show different characteristics varying with the times of the day. They are caused by traffic incidents such as accidents, disabled cars, construction activities and other unusual events. Three different major traffic conditions can be occurred: "Flow," "Dense" and "Congested". Objective of this research is to identify the current traffic condition by examining the traffic measurement parameters. The earlier researches have dealt only with speed and volume by ignoring occupancy. In our study, the occupancy is another important parameter of classification. The previous works have used multiple sensors to classify traffic condition whereas our work uses only single microwave sensor. We have extended Multiple Linear Regression classification with our new approach of Estimating with Error Prediction. We present novel algorithms of Multiclassification with One-Against-All Method and Multiclassification with Binary Comparison for multiple SVM architecture. Finaly, a non-linear model of backpropagation neural network is introduced for classification. This combination has not been reported on previous studies. Training data are obtained from the Corsim based microscopic traffic simulator TSIS 5.1. All performances are compared using this data set. Our methods are currently installed and running at traffic management center of 2.Ring Road in Istanbul.

  11. Traffic Flow Condition Classification for Short Sections Using Single Microwave Sensor

    Science.gov (United States)

    Cinsdikici, Muhammed G.; Memiş, Kemal

    2010-12-01

    Daily observed traffic flow can show different characteristics varying with the times of the day. They are caused by traffic incidents such as accidents, disabled cars, construction activities and other unusual events. Three different major traffic conditions can be occurred: "Flow," "Dense" and "Congested". Objective of this research is to identify the current traffic condition by examining the traffic measurement parameters. The earlier researches have dealt only with speed and volume by ignoring occupancy. In our study, the occupancy is another important parameter of classification. The previous works have used multiple sensors to classify traffic condition whereas our work uses only single microwave sensor. We have extended Multiple Linear Regression classification with our new approach of Estimating with Error Prediction. We present novel algorithms of Multiclassification with One-Against-All Method and Multiclassification with Binary Comparison for multiple SVM architecture. Finaly, a non-linear model of backpropagation neural network is introduced for classification. This combination has not been reported on previous studies. Training data are obtained from the Corsim based microscopic traffic simulator TSIS 5.1. All performances are compared using this data set. Our methods are currently installed and running at traffic management center of 2.Ring Road in Istanbul.

  12. Traffic Noise: A Silent Killer of Male Gamate of Albino Rats

    Directory of Open Access Journals (Sweden)

    Purushottam Pramanik , Snehangshu Biswas

    2012-01-01

    Full Text Available Objectives: The study aims to estimate the change in the weight of testis, sperm count, sperm morphology, testicular cholesterol and protein level in acute and chronic traffic noise exposed albino rats. Background: Road traffic is a significant source of noise pollution, a type of environmental stress. Traffic noise significantly increases adrenal cortical function and causes testicular dysfunction. Method: Experiment was performed on adult male albino rats. Animals were divided in to one control group and two experimental groups. Both the experimental groups were exposed to traffic noise having intensity 80 dB to 90 dB at the rate of 5 hr daily and control group was not exposed. First experimental group was exposed to traffic noise for 30 days and second group for 60 days. Testicular weight, sperm count, sperm morphology, testicular protein level and testicular cholesterol level were estimated. Statistical analysis was done using unpaired ‘t’ test. Result: Contribution of testis to body weight, testicular protein level and sperm count were low but testicular cholesterol level was more in traffic noise exposed rats than unexposed counterpart. Traffic noise exposure also increased percentage of morphologically abnormal sperm. Conclusion: Traffic noise adversely affect male gamete and such effect may be due to noise-induced suppression of testosterone synthesis.

  13. Study on Macro-traffic Model

    Institute of Scientific and Technical Information of China (English)

    FangGe; GuowuZhang; BaojunYuan; KepingLi

    2004-01-01

    Macro-traffic model is an effective tool for supporting traffic programmer to This article is based on the software products VISEM (demand model) and VISUM (supply model) from PTV Company of Germany, and studies macro-traffic model on the basis of considering that traffic system is an interactive system of between a supply system and a demand system.

  14. Assessment of Traffic Noise Impacts

    DEFF Research Database (Denmark)

    Rich, Jeppe Husted; Nielsen, Otto Anker

    2004-01-01

    A steady growth in traffic intensities in most urban areas throughout the world has forced planners and politicians to seriously consider the resulting environmental impact, such as traffic noise, accidents and air pollution. The assessment of such negative factors is needed in order to reveal...... the true social benefit of infrastructure plans. The paper presents a noise assessment model for the Copenhagen region, which brings together GIS technology and non-linear hedonic regression models to reveal the implicit costs of traffic noise measured as the marginal percentage loss in property values...... with respect to the decibel traffic noise. The model distinguishes between houses and apartments and shows that the ability to include refined accessibility variables have significant impact on estimated prices....

  15. Intelligent Ambulance Traffic Assistance System

    Directory of Open Access Journals (Sweden)

    RONOJOY GHOSH

    2013-09-01

    Full Text Available With the increase in traffic road density, several causalities occur due to delay in taking a patient to the hospital in an ambulance. In this paper, we have developed an algorithm to find the shortest path to reach the required destination. As required the software will identify the present location of the vehicle and ask the user for the destination. Then it will show all the available paths, highlighting the shortest one or in several cases the most optimum one. Further we made the traffic signals automated for special vehicles like an ambulance or a fire-engine such that the signals will go green for the ambulance as it comes in the vicinity of the traffic signal, thus providing them with a clear path to reach its destination. The original signal is restored as soon as the ambulance goes undetected by the Bluetooth scanner of the traffic signal.

  16. A multiagent urban traffic simulation

    CERN Document Server

    Tranouez, Pierrick; Langlois, Patrice

    2012-01-01

    We built a multiagent simulation of urban traffic to model both ordinary traffic and emergency or crisis mode traffic. This simulation first builds a modeled road network based on detailed geographical information. On this network, the simulation creates two populations of agents: the Transporters and the Mobiles. Transporters embody the roads themselves; they are utilitarian and meant to handle the low level realism of the simulation. Mobile agents embody the vehicles that circulate on the network. They have one or several destinations they try to reach using initially their beliefs of the structure of the network (length of the edges, speed limits, number of lanes etc.). Nonetheless, when confronted to a dynamic, emergent prone environment (other vehicles, unexpectedly closed ways or lanes, traffic jams etc.), the rather reactive agent will activate more cognitive modules to adapt its beliefs, desires and intentions. It may change its destination(s), change the tactics used to reach the destination (favorin...

  17. Automatic Traffic Recorder (ATR) Stations

    Data.gov (United States)

    Department of Homeland Security — The data included in the GIS Traffic Stations Version database have been assimilated from station description files provided by FHWA for Weigh-in-Motion (WIM), and...

  18. Estimating Emissions from Railway Traffic

    DEFF Research Database (Denmark)

    Jørgensen, Morten W.; Sorenson, Spencer C.

    1998-01-01

    Several parameters of importance for estimating emissions from railway traffic are discussed, and typical results presented. Typical emissions factors from diesel engines and electrical power generation are presented, and the effect of differences in national electrical generation sources...

  19. AAA Foundation for Traffic Safety

    Science.gov (United States)

    ... kind of road user. 1 2 3 4 Traffic Safety News Distracted driving fines are up, but ... detailed data regarding when, where, and how much people drive and goes beyond existing federal data. Research ...

  20. Reducing Network Traffic of Token Protocol Using Sharing Relation Cache

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Token protocol provides a new coherence framework for shared-memory multiprocessor systems.It avoids indirections of directory protocols for common cache-to-cache transfer misses, and achieves higher interconnect bandwidth and lower interconnect latency compared with snooping protocols. However, the broadcasting increases network traffic, limiting the scalability of token protocol. This paper describes an efficient technique to reduce the token protocol network traffic, called sharing relation cache. This cache provides destination set information for cache-to-cache miss requests by caching directory information for recent shared data. This paper introduces how to implement the technique in a token protocol. Simulations using SPLASH-2 benchmarks show that in a 16-core chip multiprocessor system, the cache reduced the network traffic by 15% on average.

  1. Automatic and efficient driving strategies while approaching a traffic light

    CERN Document Server

    Treiber, Martin

    2014-01-01

    Vehicle-infrastructure communication opens up new ways to improve traffic flow efficiency at signalized intersections. In this study, we assume that equipped vehicles can obtain information about switching times of relevant traffic lights in advance. This information is used to improve traffic flow by the strategies 'early braking', 'anticipative start', and 'flying start'. The strategies can be implemented in driver-information mode, or in automatic mode by an Adaptive Cruise Controller (ACC). Quality criteria include cycle-averaged capacity, driving comfort, fuel consumption, travel time, and the number of stops. By means of simulation, we investigate the isolated strategies and the complex interactions between the strategies and between equipped and non-equipped vehicles. As universal approach to assess equipment level effects we propose relative performance indexes and found, at a maximum speed of 50 km/h, improvements of about 15% for the number of stops and about 4% for the other criteria. All figures d...

  2. Comparison of road traffic emission models in Madrid (Spain)

    Science.gov (United States)

    Borge, Rafael; de Miguel, Isabel; de la Paz, David; Lumbreras, Julio; Pérez, Javier; Rodríguez, Encarnación

    2012-12-01

    Many cities in Europe have difficulties to meet the air quality standards set by the European legislation, most particularly the annual mean Limit Value for NO2. Road transport is often the main source of air pollution in urban areas and therefore, there is an increasing need to estimate current and future traffic emissions as accurately as possible. As a consequence, a number of specific emission models and emission factors databases have been developed recently. They present important methodological differences and may result in largely diverging emission figures and thus may lead to alternative policy recommendations. This study compares two approaches to estimate road traffic emissions in Madrid (Spain): the COmputer Programme to calculate Emissions from Road Transport (COPERT4 v.8.1) and the Handbook Emission Factors for Road Transport (HBEFA v.3.1), representative of the 'average-speed' and 'traffic situation' model types respectively. The input information (e.g. fleet composition, vehicle kilometres travelled, traffic intensity, road type, etc.) was provided by the traffic model developed by the Madrid City Council along with observations from field campaigns. Hourly emissions were computed for nearly 15 000 road segments distributed in 9 management areas covering the Madrid city and surroundings. Total annual NOX emissions predicted by HBEFA were a 21% higher than those of COPERT. The discrepancies for NO2 were lower (13%) since resulting average NO2/NOX ratios are lower for HBEFA. The larger differences are related to diesel vehicle emissions under "stop & go" traffic conditions, very common in distributor/secondary roads of the Madrid metropolitan area.In order to understand the representativeness of these results, the resulting emissions were integrated in an urban scale inventory used to drive mesoscale air quality simulations with the Community Multiscale Air Quality (CMAQ) modelling system (1 km2 resolution). Modelled NO2 concentrations were compared

  3. An Open-Source Microscopic Traffic Simulator

    CERN Document Server

    Treiber, Martin; 10.1109/MITS.2010.939208

    2010-01-01

    We present the interactive Java-based open-source traffic simulator available at www.traffic-simulation.de. In contrast to most closed-source commercial simulators, the focus is on investigating fundamental issues of traffic dynamics rather than simulating specific road networks. This includes testing theories for the spatiotemporal evolution of traffic jams, comparing and testing different microscopic traffic models, modeling the effects of driving styles and traffic rules on the efficiency and stability of traffic flow, and investigating novel ITS technologies such as adaptive cruise control, inter-vehicle and vehicle-infrastructure communication.

  4. Stochastic control of traffic patterns

    DEFF Research Database (Denmark)

    Gaididei, Yuri B.; Gorria, Carlos; Berkemer, Rainer

    2013-01-01

    A stochastic modulation of the safety distance can reduce traffic jams. It is found that the effect of random modulation on congestive flow formation depends on the spatial correlation of the noise. Jam creation is suppressed for highly correlated noise. The results demonstrate the advantage...... of heterogeneous performance of the drivers in time as well as individually. This opens the possibility for the construction of technical tools to control traffic jam formation....

  5. TrafficGen Architecture Document

    Science.gov (United States)

    2016-01-01

    Poisson, Jitter, and Clone . Researchers can experience an added dimension of network traffic visualization by pairing TrafficGen with the NRL Scripted...MVC Classes The top-level MVC classes control the workspace of the application, specifically the menu and the way the nodes and events are rendered...This is a container class that holds singleton instances of the view classes employed by this application. Because of the way this application is

  6. Future Emissions from Railway Traffic

    DEFF Research Database (Denmark)

    Sorenson, Spencer C.

    1998-01-01

    In investigation of the expected development in factors which influence railway energy consumption and emissions. Traffic factors such as train speed, load, an occupancy were considered. Tehcnical factors such an emissions factors, fleet composition and train weight were also considered. An estim......In investigation of the expected development in factors which influence railway energy consumption and emissions. Traffic factors such as train speed, load, an occupancy were considered. Tehcnical factors such an emissions factors, fleet composition and train weight were also considered...

  7. Internet Load and Traffic Balancing

    Institute of Scientific and Technical Information of China (English)

    李文正; 郭巧; 郭为民

    2005-01-01

    Load and traffic balancing for the Internet are analyzed. An intelligent domain name system(DNS) policy for the control and management of content distribution networks (CDN) is presented. An CDNs network based Urtitech IntelliDNS is built, and performance of the network in realizing traffic and load balancing is measured. It is proved that CDNs provide a valuable service and the methods are feasible.

  8. Fastlane: Traffic flow modeling and multi-class dynamic traffic management

    NARCIS (Netherlands)

    Schreiter, T.; Van Wageningen-Kessels, F.L.M.; Yuan, Y.; Van Lint, J.W.C.; Hoogendoorn, S.P.

    2012-01-01

    Dynamic Traffic Management (DTM) aims to improve traffic conditions. DTM usually consists of two steps: first the current traffic is estimated, then appropriate control actions are determined based on that estimate. In order to estimate and control the traffic, a suitable traffic flow model that rep

  9. The willingness to pay of parties to traffic accidents for loss of productivity and consolation compensation.

    Science.gov (United States)

    Jou, Rong-Chang; Chen, Tzu-Ying

    2015-12-01

    In this study, willingness to pay (WTP) for loss of productivity and consolation compensation by parties to traffic accidents is investigated using the Tobit model. In addition, WTP is compared to compensation determined by Taiwanese courts. The modelling results showed that variables such as education, average individual monthly income, traffic accident history, past experience of severe traffic accident injuries, the number of working days lost due to a traffic accident, past experience of accepting compensation for traffic accident-caused productivity loss and past experience of accepting consolation compensation caused by traffic accidents have a positive impact on WTP. In addition, average WTP for these two accident costs were obtained. We found that parties to traffic accidents were willing to pay more than 90% of the compensation determined by the court in the scenario of minor and moderate injuries. Parties were willing to pay approximately 80% of the compensation determined by the court for severe injuries, disability and fatality. Therefore, related agencies can use our study findings as the basis for determining the compensation that parties should pay for productivity losses caused by traffic accidents of different types.

  10. Supplementation of cattle fed tropical grasses with microalgae increases microbial protein production and average daily gain.

    Science.gov (United States)

    Costa, D F A; Quigley, S P; Isherwood, P; McLennan, S R; Poppi, D P

    2016-05-01

    A series of 3 experiments were conducted to evaluate the use of microalgae as supplements for ruminants consuming low-CP tropical grasses. In Exp. 1, the chemical composition and in vitro protein degradability of 9 algae species and 4 protein supplements were determined. In Exp. 2, rumen function and microbial protein (MCP) production were determined in steers fed speargrass hay alone or supplemented with , , , or cottonseed meal (CSM). In Exp. 3, DMI and ADG were determined in steers fed speargrass hay alone or supplemented with increasing amounts of NPN (urea combined with ammonia sulfate), CSM, or . In Exp. 1, the CP content of and (675 and 580 g/kg DM) was highest among the algae species and higher than the other protein supplements evaluated, and sp. had the highest crude lipid (CL) content (198 g/kg DM). In Exp. 2, supplementation increased speargrass hay intake, the efficiency of MCP production, the fractional outflow rate of digesta from the rumen, the concentration of NHN, and the molar proportion of branched-chain fatty acids in the rumen fluid of steers above all other treatments. acceptance by steers was low and this resulted in no significant difference to unsupplemented steers for all parameters measured for this algae supplement. In Exp. 3, ADG linearly increased with increasing supplementary N intake from both and NPN, with no difference between the 2 supplements. In contrast, ADG quadratically increased with increasing supplementary N intake from CSM. It was concluded that and may potentially be used as protein sources for cattle grazing low-CP pastures.

  11. Classification of Automated Search Traffic

    Science.gov (United States)

    Buehrer, Greg; Stokes, Jack W.; Chellapilla, Kumar; Platt, John C.

    As web search providers seek to improve both relevance and response times, they are challenged by the ever-increasing tax of automated search query traffic. Third party systems interact with search engines for a variety of reasons, such as monitoring a web site’s rank, augmenting online games, or possibly to maliciously alter click-through rates. In this paper, we investigate automated traffic (sometimes referred to as bot traffic) in the query stream of a large search engine provider. We define automated traffic as any search query not generated by a human in real time. We first provide examples of different categories of query logs generated by automated means. We then develop many different features that distinguish between queries generated by people searching for information, and those generated by automated processes. We categorize these features into two classes, either an interpretation of the physical model of human interactions, or as behavioral patterns of automated interactions. Using the these detection features, we next classify the query stream using multiple binary classifiers. In addition, a multiclass classifier is then developed to identify subclasses of both normal and automated traffic. An active learning algorithm is used to suggest which user sessions to label to improve the accuracy of the multiclass classifier, while also seeking to discover new classes of automated traffic. Performance analysis are then provided. Finally, the multiclass classifier is used to predict the subclass distribution for the search query stream.

  12. Preliminary Benefits Assessment of Traffic Aware Strategic Aircrew Requests (TASAR)

    Science.gov (United States)

    Henderson, Jeff; Idris, Husni; Wing, David J.

    2012-01-01

    While en route, aircrews submit trajectory change requests to air traffic control (ATC) to better meet their objectives including reduced delays, reduced fuel burn, and passenger comfort. Aircrew requests are currently made with limited to no information on surrounding traffic. Consequently, these requests are uninformed about a key ATC objective, ensuring traffic separation, and therefore less likely to be accepted than requests informed by surrounding traffic and that avoids creating conflicts. This paper studies the benefits of providing aircrews with on-board decision support to generate optimized trajectory requests that are probed and cleared of known separation violations prior to issuing the request to ATC. These informed requests are referred to as traffic aware strategic aircrew requests (TASAR) and leverage traffic surveillance information available through Automatic Dependent Surveillance Broadcast (ADS-B) In capability. Preliminary fast-time simulation results show increased benefits with longer stage lengths since beneficial trajectory changes can be applied over a longer distance. Also, larger benefits were experienced between large hub airports as compared to other airport sizes. On average, an aircraft equipped with TASAR reduced its travel time by about one to four minutes per operation and fuel burn by about 50 to 550 lbs per operation depending on the objective of the aircrew (time, fuel, or weighted combination of time and fuel), class of airspace user, and aircraft type. These preliminary results are based on analysis of approximately one week of traffic in July 2012 and additional analysis is planned on a larger data set to confirm these initial findings.

  13. Self-control of traffic lights and vehicle flows in urban road networks

    Science.gov (United States)

    Lämmer, Stefan; Helbing, Dirk

    2008-04-01

    Based on fluid-dynamic and many-particle (car-following) simulations of traffic flows in (urban) networks, we study the problem of coordinating incompatible traffic flows at intersections. Inspired by the observation of self-organized oscillations of pedestrian flows at bottlenecks, we propose a self-organization approach to traffic light control. The problem can be treated as a multi-agent problem with interactions between vehicles and traffic lights. Specifically, our approach assumes a priority-based control of traffic lights by the vehicle flows themselves, taking into account short-sighted anticipation of vehicle flows and platoons. The considered local interactions lead to emergent coordination patterns such as 'green waves' and achieve an efficient, decentralized traffic light control. While the proposed self-control adapts flexibly to local flow conditions and often leads to non-cyclical switching patterns with changing service sequences of different traffic flows, an almost periodic service may evolve under certain conditions and suggests the existence of a spontaneous synchronization of traffic lights despite the varying delays due to variable vehicle queues and travel times. The self-organized traffic light control is based on an optimization and a stabilization rule, each of which performs poorly at high utilizations of the road network, while their proper combination reaches a superior performance. The result is a considerable reduction not only in the average travel times, but also of their variation. Similar control approaches could be applied to the coordination of logistic and production processes.

  14. Revealing daily travel patterns and city structure with taxi trip data

    CERN Document Server

    Liu, Xi; Gong, Yongxi; Liu, Yu

    2013-01-01

    Detecting regional spatial structures based on spatial interactions is crucial in applications ranging from urban planning to traffic control. In the big data era, various movement trajectories are available for studying spatial structures. This research uses large scale Shanghai taxi trip data extracted from GPS-enabled taxi trajectories to reveal traffic flow patterns and urban structure of the city. Using the network science methods, 15 temporally stable regions reflecting the scope of people's daily travels are found using community detection method on the network built from short trips, which represent residents' daily intra-urban travels and exhibit a clear pattern. In each region, taxi traffic flows are dominated by a few 'hubs' and 'hubs' in suburbs impact more trips than 'hubs' in urban areas. Land use conditions in urban regions are different from those in suburban areas. Additionally, 'hubs' in urban area associate with office buildings and commercial areas more, whereas residential land use is mor...

  15. On the Digital Daily Cycles of Individuals

    CERN Document Server

    Aledavood, Talayeh; Saramäki, Jari

    2015-01-01

    Humans, like almost all animals, are phase-locked to the diurnal cycle. Most of us sleep at night and are active through the day. Because we have evolved to function with this cycle, the circadian rhythm is deeply ingrained and even detectable at the biochemical level. However, within the broader day-night pattern, there are individual differences: e.g., some of us are intrinsically morning-active, while others prefer evenings. In this article, we look at digital daily cycles: circadian patterns of activity viewed through the lens of auto-recorded data of communication and online activity. We begin at the aggregate level, discuss earlier results, and illustrate differences between population-level daily rhythms in different media. Then we move on to the individual level, and show that there is a strong individual-level variation beyond averages: individuals typically have their distinctive daily pattern that persists in time. We conclude by discussing the driving forces behind these signature daily patterns, ...

  16. Relationship between Black Carbon and heavy traffic in São Paulo, Brazil

    Science.gov (United States)

    Miranda, R. M.; Perez-Martinez, P.; Ribeiro, F. N. D.; Andrade, M. D. F.

    2015-12-01

    Carbonaceous aerosols play an important role in air quality, human health and global climate change. Black Carbon (BC) can be considered the most efficient light absorber in the visible spectrum and is mainly found in the fine fraction of aerosol. Typically is emitted by incomplete combustion of fossil fuels related to traffic, industrial processes and biomass burning. São Paulo Metropolitan Area (SPMA) with more than 19 million inhabitants, 7 million vehicles, as well as the major industrial and technological park of the country, has high concentrations of air pollutants, especially in the winter and vehicles are considered the principal source of particles emitted to the atmosphere. Since November 2014, Black Carbon and PM2.5 are being monitored using a MAAP (Multi Angle Absorption Photometer) Thermo 5012 and a Dust Trak DRX-8533 TSI in the East Campus of University of São Paulo, close to important highways and also to the largest airport of Brazil (Guarulhos Airport). Average BC concentration was 1.7 μg/m3 with some peaks above 17.0 μg/m3 and for PM2.5 average was 10.2 μg/m3. Particle concentrations reached values greater than the air quality standard (60 μg/m3) in the winter months. Winds coming from the East direction predominate. Traffic restrictions to heavy duty vehicles in the road-rings next to the sampling site during some hours of the day are the responsible for the daily BC and PM2.5 behavior (figure below), where high concentrations occur early in the morning and late at night, when heavy diesel vehicles are released for transit. Seasonal variations are different for BC and PM2.5 due to local sources of BC and meteorological conditions that have more influence on the particles. The weekly variation indicates that concentrations are lower on Sundays and higher from Tuesday to Thursday. Emission factors for BC were calculated based on traffic information.

  17. Traffic behavior of mixed traffic flow with two kinds of different self-stabilizing control vehicles

    Science.gov (United States)

    Li, Zhipeng; Li, Wenzhong; Xu, Shangzhi; Qian, Yeqing; Sun, Jian

    2015-10-01

    In this paper, we propose a heterogeneous car following model in terms of an extension to the original optimal velocity model characterizing two classes of different self-stabilizing control vehicles. Linear stability analysis method is utilized to the extended model, for purpose to explore how the varying percentages of the vehicles with short-duration self-stabilizing control influence the stability of the heterogeneous traffic flow. We obtain the neutral stability lines for different percentages of two classes of vehicles, with finding that the traffic flow trends to stable with the decrease of the percentage for short-duration self-stabilizing control vehicles. Moreover, we explore a special case that the same numbers of two different classes of vehicles with self-stabilizing control. We theoretically derive the stability condition of the special case, and conclude the effect of the average value and the standard deviation of two time gaps, on the heterogeneous traffic stability. At last, direct simulations are conducted to verify the conclusion of theoretical analysis.

  18. The monthly-averaged and yearly-averaged cosine effect factor of a heliostat field

    Energy Technology Data Exchange (ETDEWEB)

    Al-Rabghi, O.M.; Elsayed, M.M. (King Abdulaziz Univ., Jeddah (Saudi Arabia). Dept. of Thermal Engineering)

    1992-01-01

    Calculations are carried out to determine the dependence of the monthly-averaged and the yearly-averaged daily cosine effect factor on the pertinent parameters. The results are plotted on charts for each month and for the full year. These results cover latitude angles between 0 and 45[sup o]N, for fields with radii up to 50 tower height. In addition, the results are expressed in mathematical correlations to facilitate using them in computer applications. A procedure is outlined to use the present results to preliminary layout the heliostat field, and to predict the rated MW[sub th] reflected by the heliostat field during a period of a month, several months, or a year. (author)

  19. Vocal attractiveness increases by averaging.

    Science.gov (United States)

    Bruckert, Laetitia; Bestelmeyer, Patricia; Latinus, Marianne; Rouger, Julien; Charest, Ian; Rousselet, Guillaume A; Kawahara, Hideki; Belin, Pascal

    2010-01-26

    Vocal attractiveness has a profound influence on listeners-a bias known as the "what sounds beautiful is good" vocal attractiveness stereotype [1]-with tangible impact on a voice owner's success at mating, job applications, and/or elections. The prevailing view holds that attractive voices are those that signal desirable attributes in a potential mate [2-4]-e.g., lower pitch in male voices. However, this account does not explain our preferences in more general social contexts in which voices of both genders are evaluated. Here we show that averaging voices via auditory morphing [5] results in more attractive voices, irrespective of the speaker's or listener's gender. Moreover, we show that this phenomenon is largely explained by two independent by-products of averaging: a smoother voice texture (reduced aperiodicities) and a greater similarity in pitch and timbre with the average of all voices (reduced "distance to mean"). These results provide the first evidence for a phenomenon of vocal attractiveness increases by averaging, analogous to a well-established effect of facial averaging [6, 7]. They highlight prototype-based coding [8] as a central feature of voice perception, emphasizing the similarity in the mechanisms of face and voice perception.

  20. MOPITT Gridded Daily CO Retrievals (Near and Thermal Infrared Radiances) V006

    Data.gov (United States)

    National Aeronautics and Space Administration — This product averages the daily L2 swath data into a 1x1 degree grid. Day and night passes are kept separate. Averaging kernels for each retrieval are provided...

  1. Daily Water Use in Nine Cities

    Science.gov (United States)

    Maidment, David R.; Miaou, Shaw-Pin

    1986-06-01

    Transfer functions are used to model the short-term response of daily municipal water use to rainfall and air temperature variations. Daily water use data from nine cities are studied, three cities each from Florida, Pennsylvania, and Texas. The dynamic response of water use to rainfall and air temperature is similar across the cities within each State; in addition the responses of the Texas and Florida cities are very similar to one another while the response of the Pennsylvania cities is more sensitive to air temperature and less to rainfall. There is little impact of city size on the response functions. The response of water use to rainfall depends first on the occurrence of rainfall and second on its magnitude. The occurrence of a rainfall more than 0.05 in./day (0.13 cm/day) causes a drop in the seasonal component of water use one day later that averages 38% for the Texas cities, 42% for the Florida cities, and 7% for the Pennsylvania cities. In Austin, Texas, a spatially averaged rainfall series shows a clearer relationship with water use than does rainfall data from a single gage. There is a nonlinear response of water use to air temperature changes with no response for daily maximum air temperatures between 40° and 70°F (4-21°C) an increase in water use with air temperature beyond 70°F; above 85°-90°F (29°-32°C) water use increases 3-5 times more per degree than below that limit in Texas and Florida. The model resulting from these studies can be used for daily water use forecasting and water conservation analysis.

  2. Synchronized flow in oversaturated city traffic.

    Science.gov (United States)

    Kerner, Boris S; Klenov, Sergey L; Hermanns, Gerhard; Hemmerle, Peter; Rehborn, Hubert; Schreckenberg, Michael

    2013-11-01

    Based on numerical simulations with a stochastic three-phase traffic flow model, we reveal that moving queues (moving jams) in oversaturated city traffic dissolve at some distance upstream of the traffic signal while transforming into synchronized flow. It is found that, as in highway traffic [Kerner, Phys. Rev. E 85, 036110 (2012)], such a jam-absorption effect in city traffic is explained by a strong driver's speed adaptation: Time headways (space gaps) between vehicles increase upstream of a moving queue (moving jam), resulting in moving queue dissolution. It turns out that at given traffic signal parameters, the stronger the speed adaptation effect, the shorter the mean distance between the signal location and the road location at which moving queues dissolve fully and oversaturated traffic consists of synchronized flow only. A comparison of the synchronized flow in city traffic found in this Brief Report with synchronized flow in highway traffic is made.

  3. Percolation properties in a traffic model

    CERN Document Server

    Wang, Feilong; Xu, Xiaoyun; Wu, Ruoqian; Havlin, Shlomo

    2015-01-01

    As a dynamical complex system, traffic is characterized by a transition from free flow to congestions, which is mostly studied in highways. However, despite its importance in developing congestion mitigation strategies, the understanding of this common traffic phenomenon in a city-scale is still missing. An open question is how the traffic in the network collapses from a global efficient traffic to isolated local flows in small clusters, i.e. the question of traffic percolation. Here we study the traffic percolation properties on a lattice by simulation of an agent-based model for traffic. A critical traffic volume in this model distinguishes the free-state from congested state of traffic. Our results show that the threshold of traffic percolation decreases with increasing traffic volume and reaches a minimum value at the critical traffic volume. We show that this minimal threshold is the result of longest spatial correlation between traffic flows at the critical traffic volume. These findings may help to dev...

  4. Averaged Electroencephalic Audiometry in Infants

    Science.gov (United States)

    Lentz, William E.; McCandless, Geary A.

    1971-01-01

    Normal, preterm, and high-risk infants were tested at 1, 3, 6, and 12 months of age using averaged electroencephalic audiometry (AEA) to determine the usefulness of AEA as a measurement technique for assessing auditory acuity in infants, and to delineate some of the procedural and technical problems often encountered. (KW)

  5. Ergodic averages via dominating processes

    DEFF Research Database (Denmark)

    Møller, Jesper; Mengersen, Kerrie

    2006-01-01

    We show how the mean of a monotone function (defined on a state space equipped with a partial ordering) can be estimated, using ergodic averages calculated from upper and lower dominating processes of a stationary irreducible Markov chain. In particular, we do not need to simulate the stationary ...

  6. Logistiline Daily Service / Paavo Kangur

    Index Scriptorium Estoniae

    Kangur, Paavo, 1966-

    2005-01-01

    Sügisel ostis Leedu endise majandusministri Valetntinas Milaknise firma Daily Service ära kõik bürootarvetemüüja Reval Impexi aktsiad. 300 miljoni kroonise aastakäibega firma Eesti tütarettevõte prognoosib oma tänavuseks käibeks 31,2 miljonit krooni. Lisa: Daily Service'i struktuur

  7. Disorder effect on the traffic flow behavior

    Science.gov (United States)

    Ez-Zahraouy, H.; Benyoussef, A.

    2008-08-01

    The effects of some disorders, on the traffic flow behavior, are studied numerically. Especially, the effect of mixture of vehicles of different velocities and/or lengths, the effects of different drivers reactions, the position and the extraction rate of off-ramp in the free way. Using a generalized optimal velocity model, for a mixture of fast and slow vehicles, we have investigated the effect of delay times τ f and τ s on the fundamental diagram. It is Found that the small delay times have almost no effect, while, for sufficiently large delay time τ s , the current profile displays qualitatively five different forms, depending on τ f , τ s and the fractions f f and f s of the fast and slow cars, respectively. The velocity (current) exhibits first-order transitions at low and/or high densities, from freely moving phase to the congested state, and from congested state to a jamming one, respectively. The minimal current appears in intermediate values of τ s . Furthermore there exist, a critical value of τ f above which the meta-stability and hysteresis appear. The effects of disorder due to drivers behaviors have been introduced through a random delay time τ allowing the car to reach its optimal velocity traffic flow models with open boundaries. In the absence of the variation of the delay time Δτ, it is found that the transition from unstable to meta-stable and from meta-stable to stable state occur under the effect of the injecting and the extracting rate probabilities α and β respectively. Moreover, the perturbation of the traffic flow behavior due to the off-ramp has been studied using numerical simulations in the one dimensional cellular automaton traffic flow model with open boundaries. When the off-ramp is located between two critical positions i c1 and i c2 the current remains constant (plateau) for β0 c1 < β0 < β0 c2, and the density undergoes two successive first order transitions: from high density to plateau current phase and from average

  8. Transport growth in Bangkok: Energy, environment, and traffic congestion. Workshop proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Philpott, J. [Asia Regional Office, Bangkok (Thailand)

    1995-07-01

    Bangkok, the capital of Thailand, is a physically and economically complexcity with a complicated transport system. With daily traffic congestion averaging 16 hours, the air quality is such that to breathe street level pollution for 8 eight hours is roughly equivalent to smoking nine cigarettes per day. Estimates suggest idling traffic costs up to $1.6 billion annually. Energy use within the transport sector is on a steady rise with an estimated increase in 11 years of two and one half times. Severe health impacts have begun to effect many residents - young children and the elderly being particularly vulnerable. Bangkok`s air quality and congestion problems are far from hopeless. Great potential exists for Bangkok to remedy its transport-related problems. The city has many necessary characteristics that allow an efficient, economical system of transport. For example, its high density level makes the city a prime candidate for an efficient system of mass transit and the multitude and close proximity of shops, street vendors, restaurants, and residential areas is highly conducive to walking and cycling. Technical knowledge and capacity to devise and implement innovative policies and projects to address air quality and congestion problems is plentiful. There is also consensus among Bangkokians that something needs to be done immediately to clear the air and the roads. However, little has been done. This report proposes a new approach to transport planning for Bangkok that integrates consideration of ecological, social, and financial viability in the process of making decisions regarding managing existing infrastructure and investments in new infrastructure. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.

  9. Traffic Signal Using Smart Agent System

    Directory of Open Access Journals (Sweden)

    Cheonshik Kim

    2008-01-01

    Full Text Available In this research, we propose an electro-sensitive traffic light using the smart agent algorithm to reduce traffic congestion and traffic accidents. The multi-agent system approach can provide a new and preferable solution. The proposed method adaptively controls the cycle of traffic signals even though the traffic volume varies. Consequently, we reduce the car waiting time and start-up delay time using fuzzy control of feedback data. In particular, we have designed and implemented a system to create optimum traffic signals in congested conditions. The effectiveness of this method was shown through simulation of multiple intersections.

  10. Structure Model of Urban Traffic System Evolution

    Institute of Scientific and Technical Information of China (English)

    JIANG Ke-jin; ZHANG Dian-ye

    2008-01-01

    A structure model of urban traffic system evolution is built based on the analysis of the factors influencing the system evolution and the hierarchy between the factors. Then the influencing degrees of the factors are quantificationally analyzed by DEMATE (decision making trial and evaluation laboratory). The analysis results indicate that the traffic mode structure which achieves the highest central degree is the dominant influencing factor of the urban traffic system evolution, and that economy development and the traffic poficy axe the second important factors that also affect the traffic mode structures. Furthermore, physical geography is a basic restriction to the urban traffic system evolution.

  11. Simulation Model of Traffic Jam at Crossroads

    Directory of Open Access Journals (Sweden)

    Mladen Kalajžić

    2002-11-01

    Full Text Available Traffic congestion is one of the major problems in most cities.It is the consequence of unavoidable motorization, butalso, in many cases, of improper solutions considering constructionof roads or organisation of traffic.This paper deals with one problematic crossroad in thetown of Zadar in which traffic jams occur due to poor organisationof traffic. Using mathematical simulation, the first partproves that traffic jams will certainly occur, and in the secondpart, crossroads signalling is considered as a possible solutionwhich, if combined with intelligent control could significantlyimprove the organisation of traffic at this crossroads.

  12. Hidden geometry of traffic jamming

    Science.gov (United States)

    Andjelković, Miroslav; Gupte, Neelima; Tadić, Bosiljka

    2015-05-01

    We introduce an approach based on algebraic topological methods that allow an accurate characterization of jamming in dynamical systems with queues. As a prototype system, we analyze the traffic of information packets with navigation and queuing at nodes on a network substrate in distinct dynamical regimes. A temporal sequence of traffic density fluctuations is mapped onto a mathematical graph in which each vertex denotes one dynamical state of the system. The coupling complexity between these states is revealed by classifying agglomerates of high-dimensional cliques that are intermingled at different topological levels and quantified by a set of geometrical and entropy measures. The free-flow, jamming, and congested traffic regimes result in graphs of different structure, while the largest geometrical complexity and minimum entropy mark the edge of the jamming region.

  13. On vehicular traffic data analysis

    Energy Technology Data Exchange (ETDEWEB)

    Brics, Martins; Mahnke, Reinhard [Institute of Physics, Rostock University (Germany)

    2011-07-01

    This contribution consists of analysis of empirical vehicular traffic flow data. The main focus lies on the Next Generation Simulation (NGSIM) data. The first findings show that there are artificial structures within the data due to errors of monitoring as well as smoothing position measurement data. As a result speed data show discretisation in 5 feet per second. The aim of this investigation is to construct microscopic traffic flow models which are in agreement to the analysed empirical data. The ongoing work follows the subject of research summarized by Christof Liebe in his PhD thesis entitled ''Physics of traffic flow: Empirical data and dynamical models'' (Rostock, 2010).

  14. Dependability in Aggregation by Averaging

    CERN Document Server

    Jesus, Paulo; Almeida, Paulo Sérgio

    2010-01-01

    Aggregation is an important building block of modern distributed applications, allowing the determination of meaningful properties (e.g. network size, total storage capacity, average load, majorities, etc.) that are used to direct the execution of the system. However, the majority of the existing aggregation algorithms exhibit relevant dependability issues, when prospecting their use in real application environments. In this paper, we reveal some dependability issues of aggregation algorithms based on iterative averaging techniques, giving some directions to solve them. This class of algorithms is considered robust (when compared to common tree-based approaches), being independent from the used routing topology and providing an aggregation result at all nodes. However, their robustness is strongly challenged and their correctness often compromised, when changing the assumptions of their working environment to more realistic ones. The correctness of this class of algorithms relies on the maintenance of a funda...

  15. High average power supercontinuum sources

    Indian Academy of Sciences (India)

    J C Travers

    2010-11-01

    The physical mechanisms and basic experimental techniques for the creation of high average spectral power supercontinuum sources is briefly reviewed. We focus on the use of high-power ytterbium-doped fibre lasers as pump sources, and the use of highly nonlinear photonic crystal fibres as the nonlinear medium. The most common experimental arrangements are described, including both continuous wave fibre laser systems with over 100 W pump power, and picosecond mode-locked, master oscillator power fibre amplifier systems, with over 10 kW peak pump power. These systems can produce broadband supercontinua with over 50 and 1 mW/nm average spectral power, respectively. Techniques for numerical modelling of the supercontinuum sources are presented and used to illustrate some supercontinuum dynamics. Some recent experimental results are presented.

  16. Traffic resource allocation for complex networks

    Institute of Scientific and Technical Information of China (English)

    Ling Xiang; Hu Mao-Bin; Long Jian-Cheng; Ding Jian-Xun; Shi Qin

    2013-01-01

    In this paper,an optimal resource allocation strategy is proposed to enhance traffic dynamics in complex networks.The network resources are the total node packet-delivering capacity and the total link bandwidth.An analytical method is developed to estimate the overall network capacity by using the concept of efficient betweenness (ratio of algorithmic betweenness and local processing capacity).Three network structures (scale-free,small-world,and random networks) and two typical routing protocols (shortest path protocol and efficient routing protocol) are adopted to demonstrate the performance of the proposed strategy.Our results show that the network capacity is reversely proportional to the average path length for a particular routing protocol and the shortest path protocol can achieve the largest network capacity when the proposed resource allocation strategy is adopted.

  17. Daily and Sub-daily Precipitation for the Former USSR

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset is a compilation of in situ daily and hourly meteorological observations for the former USSR initially obtained within the framework of several joint...

  18. Measuring Complexity through Average Symmetry

    OpenAIRE

    Alamino, Roberto C.

    2015-01-01

    This work introduces a complexity measure which addresses some conflicting issues between existing ones by using a new principle - measuring the average amount of symmetry broken by an object. It attributes low (although different) complexity to either deterministic or random homogeneous densities and higher complexity to the intermediate cases. This new measure is easily computable, breaks the coarse graining paradigm and can be straightforwardly generalised, including to continuous cases an...

  19. Traffic and Granular Flow '11

    CERN Document Server

    Buslaev, Alexander; Bugaev, Alexander; Yashina, Marina; Schadschneider, Andreas; Schreckenberg, Michael; TGF11

    2013-01-01

    This book continues the biannual series of conference proceedings, which has become a classical reference resource in traffic and granular research alike. It addresses new developments at the interface between physics, engineering and computational science. Complex systems, where many simple agents, be they vehicles or particles, give rise to surprising and fascinating phenomena.   The contributions collected in these proceedings cover several research fields, all of which deal with transport. Topics include highway, pedestrian and internet traffic, granular matter, biological transport, transport networks, data acquisition, data analysis and technological applications. Different perspectives, i.e. modeling, simulations, experiments and phenomenological observations, are considered.

  20. Traffic-Sign Recognition Systems

    CERN Document Server

    Escalera, Sergio

    2011-01-01

    This work presents a full generic approach to the detection and recognition of traffic signs. The approach is based on the latest computer vision methods for object detection, and on powerful methods for multiclass classification. The challenge was to robustly detect a set of different sign classes in real time, and to classify each detected sign into a large, extensible set of classes. To address this challenge, several state-of-the-art methods were developed that can be used for different recognition problems. Following an introduction to the problems of traffic sign detection and categoriza

  1. Agent Based Individual Traffic Guidance

    DEFF Research Database (Denmark)

    Wanscher, Jørgen

    This thesis investigates the possibilities in applying Operations Research (OR) to autonomous vehicular traffic. The explicit difference to most other research today is that we presume that an agent is present in every vehicle - hence Agent Based Individual Traffic guidance (ABIT). The next...... evolutionary step for the in-vehicle route planners is the introduction of two-way communication. We presume that the agent is capable of exactly this. Based on this presumption we discuss the possibilities and define a taxonomy and use this to discuss the ABIT system. Based on a set of scenarios we conclude...

  2. Traffic of molecular motors: from theory to experiments

    CERN Document Server

    Pierobon, Paolo

    2007-01-01

    Intracellular transport along microtubules or actin filaments, powered by molecular motors such as kinesins, dyneins or myosins, has been recently modeled using one-dimensional driven lattice gases. We discuss some generalizations of these models, that include extended particles and defects. We investigate the feasibility of single molecule experiments aiming to measure the average motor density and to locate the position of traffic jams by mean of a tracer particle. Finally, we comment on preliminary single molecule experiments performed in living cells.

  3. Safety in traffic for vulnerable military road users

    Directory of Open Access Journals (Sweden)

    Aleksandar J. Bulajić

    2012-04-01

    Full Text Available The Army of Serbia, as a relatively closed system, regulates the field of traffic safety; however, during peacetime, general rules apply to all participants in traffic circulation. The Republic of Serbia is in the group of countries with a high number of road fatalities. The level of traffic safety in the Serbian Army has been on constant increase since 2000, although the relevant transport authorities in the military are not yet satisfied with the achieved level (even one lost life is too much. The increase can be deceptive, since if we take into account the substantial reduction in vehicle use due to various factors in the last few years (poor financial situation in the country as well as in the military, under-investment in the purchase of new vehicles, purchase of transportation services, fewer drivers drafted and more vehicles driven by trained officers, etc., it is not surprising that there are fewer accidents and fewer road deaths and injuries among military personnel. This paper aims at approaching the problem of pedestrian safety as a segment of road safety and at making an educational impact on all members of the military, because they all participate in traffic daily, if not as drivers or passengers, then certainly in large numbers as pedestrians. The basis of this paper is aimed at shedding light on the causes of pedestrian road fatalities due to their mistakes, i. e. 'negligence' of the participants in car accidents with the participation of pedestrians, as well as at proposing measures to reduce and prevent traffic accidents with pedestrians.

  4. Traffic dynamics on two-layer complex networks with limited delivering capacity

    Science.gov (United States)

    Ma, Jinlong; Han, Weizhan; Guo, Qing; Wang, Zhenyong

    2016-08-01

    The traffic dynamics of multi-layer networks has attracted a great deal of interest since many real networks are comprised of two or more layers of subnetworks. Due to its low traffic capacity, the average delivery capacity allocation strategy is susceptible to congestion with the wildly used shortest path routing protocol on two-layer complex networks. In this paper, we introduce a delivery capacity allocation strategy into the traffic dynamics on two-layer complex networks and focus on its effect on the traffic capacity measured by the critical point Rc of phase transition from free flow to congestion. When the total nodes delivering capacity is fixed, the delivering capacity of each node in physical layer is assigned to the degree distributions of both the physical and logical layers. Simulation results show that the proposed strategy can bring much better traffic capacity than that with the average delivery capacity allocation strategy. Because of the significantly improved traffic performance, this work may be useful for optimal design of networked traffic dynamics.

  5. Two-dimensional cellular automaton model of traffic flow with open boundaries

    CERN Document Server

    Tadaki, S I

    1996-01-01

    A two-dimensional cellular automaton model of traffic flow with open boundaries are investigated by computer simulations. The outflow of cars from the system and the average velocity are investigated. The time sequences of the outflow and average velocity have flicker noises in a jamming phase. The low density behavior are discussed with simple jam-free approximation.

  6. A Survey on Urban Traffic Management System Using Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Kapileswar Nellore

    2016-01-01

    Full Text Available Nowadays, the number of vehicles has increased exponentially, but the bedrock capacities of roads and transportation systems have not developed in an equivalent way to efficiently cope with the number of vehicles traveling on them. Due to this, road jamming and traffic correlated pollution have increased with the associated adverse societal and financial effect on different markets worldwide. A static control system may block emergency vehicles due to traffic jams. Wireless Sensor networks (WSNs have gained increasing attention in traffic detection and avoiding road congestion. WSNs are very trendy due to their faster transfer of information, easy installation, less maintenance, compactness and for being less expensive compared to other network options. There has been significant research on Traffic Management Systems using WSNs to avoid congestion, ensure priority for emergency vehicles and cut the Average Waiting Time (AWT of vehicles at intersections. In recent decades, researchers have started to monitor real-time traffic using WSNs, RFIDs, ZigBee, VANETs, Bluetooth devices, cameras and infrared signals. This paper presents a survey of current urban traffic management schemes for priority-based signalling, and reducing congestion and the AWT of vehicles. The main objective of this survey is to provide a taxonomy of different traffic management schemes used for avoiding congestion. Existing urban traffic management schemes for the avoidance of congestion and providing priority to emergency vehicles are considered and set the foundation for further research.

  7. A Survey on Urban Traffic Management System Using Wireless Sensor Networks.

    Science.gov (United States)

    Nellore, Kapileswar; Hancke, Gerhard P

    2016-01-27

    Nowadays, the number of vehicles has increased exponentially, but the bedrock capacities of roads and transportation systems have not developed in an equivalent way to efficiently cope with the number of vehicles traveling on them. Due to this, road jamming and traffic correlated pollution have increased with the associated adverse societal and financial effect on different markets worldwide. A static control system may block emergency vehicles due to traffic jams. Wireless Sensor networks (WSNs) have gained increasing attention in traffic detection and avoiding road congestion. WSNs are very trendy due to their faster transfer of information, easy installation, less maintenance, compactness and for being less expensive compared to other network options. There has been significant research on Traffic Management Systems using WSNs to avoid congestion, ensure priority for emergency vehicles and cut the Average Waiting Time (AWT) of vehicles at intersections. In recent decades, researchers have started to monitor real-time traffic using WSNs, RFIDs, ZigBee, VANETs, Bluetooth devices, cameras and infrared signals. This paper presents a survey of current urban traffic management schemes for priority-based signalling, and reducing congestion and the AWT of vehicles. The main objective of this survey is to provide a taxonomy of different traffic management schemes used for avoiding congestion. Existing urban traffic management schemes for the avoidance of congestion and providing priority to emergency vehicles are considered and set the foundation for further research.

  8. Comparison of classical statistical methods and artificial neural network in traffic noise prediction

    Energy Technology Data Exchange (ETDEWEB)

    Nedic, Vladimir, E-mail: vnedic@kg.ac.rs [Faculty of Philology and Arts, University of Kragujevac, Jovana Cvijića bb, 34000 Kragujevac (Serbia); Despotovic, Danijela, E-mail: ddespotovic@kg.ac.rs [Faculty of Economics, University of Kragujevac, Djure Pucara Starog 3, 34000 Kragujevac (Serbia); Cvetanovic, Slobodan, E-mail: slobodan.cvetanovic@eknfak.ni.ac.rs [Faculty of Economics, University of Niš, Trg kralja Aleksandra Ujedinitelja, 18000 Niš (Serbia); Despotovic, Milan, E-mail: mdespotovic@kg.ac.rs [Faculty of Engineering, University of Kragujevac, Sestre Janjic 6, 34000 Kragujevac (Serbia); Babic, Sasa, E-mail: babicsf@yahoo.com [College of Applied Mechanical Engineering, Trstenik (Serbia)

    2014-11-15

    Traffic is the main source of noise in urban environments and significantly affects human mental and physical health and labor productivity. Therefore it is very important to model the noise produced by various vehicles. Techniques for traffic noise prediction are mainly based on regression analysis, which generally is not good enough to describe the trends of noise. In this paper the application of artificial neural networks (ANNs) for the prediction of traffic noise is presented. As input variables of the neural network, the proposed structure of the traffic flow and the average speed of the traffic flow are chosen. The output variable of the network is the equivalent noise level in the given time period L{sub eq}. Based on these parameters, the network is modeled, trained and tested through a comparative analysis of the calculated values and measured levels of traffic noise using the originally developed user friendly software package. It is shown that the artificial neural networks can be a useful tool for the prediction of noise with sufficient accuracy. In addition, the measured values were also used to calculate equivalent noise level by means of classical methods, and comparative analysis is given. The results clearly show that ANN approach is superior in traffic noise level prediction to any other statistical method. - Highlights: • We proposed an ANN model for prediction of traffic noise. • We developed originally designed user friendly software package. • The results are compared with classical statistical methods. • The results are much better predictive capabilities of ANN model.

  9. Traffic-light labels could reduce population intakes of calories, total fat, saturated fat, and sodium

    Science.gov (United States)

    Emrich, Teri E.; Qi, Ying; Lou, Wendy Y.; L’Abbe, Mary R.

    2017-01-01

    Traffic-light labelling has been proposed as a public health intervention to improve the dietary intakes of consumers. OBJECTIVES: to model the potential impact of avoiding foods with red traffic lights on the label on the energy, total fat, saturated fat, sodium, and sugars intakes of Canadian adults. METHODS: Canadian adults aged 19 and older (n = 19,915) who responded to the Canadian Community Health Survey (CCHS), Cycle 2.2. The nutrient levels in foods consumed by Canadians in CCHS were profiled using the United Kingdom’s criteria for traffic light labelling. Whenever possible, foods assigned a red traffic light for one or more of the profiled nutrients were replaced with a similar food currently sold in Canada, with nutrient levels not assigned any red traffic lights. Average intakes of calories, total fat, saturated fat, sodium, and sugars under the traffic light scenario were compared with actual intakes of calories and these nutrients (baseline) reported in CCHS. RESULTS: Under the traffic light scenario, Canadian’s intake of energy, total fat, saturated fat, and sodium were significantly reduced compared to baseline; sugars intakes were not significantly reduced. Calorie intake was reduced by 5%, total fat 13%, saturated fat 14%, and sodium 6%. CONCLUSION: Governments and policy makers should consider the adoption of traffic light labelling as a population level intervention to improve dietary intakes and chronic disease risk. PMID:28182630

  10. Suppressing traffic-driven epidemic spreading by use of the efficient routing protocol

    CERN Document Server

    Yang, Han-Xin

    2015-01-01

    Despite extensive work on the interplay between traffic dynamics and epidemic spreading, the control of epidemic spreading by routing strategies has not received adequate attention. In this paper, we study the impact of efficient routing protocol on epidemic spreading. In the case of infinite node-delivery capacity, where the traffic is free of congestion, we find that that there exists optimal values of routing parameter, leading to the maximal epidemic threshold. This means that epidemic spreading can be effectively controlled by fine tuning the routing scheme. Moreover, we find that an increase in the average network connectivity and the emergence of traffic congestion can suppress the epidemic outbreak.

  11. Throughput-Based Traffic Steering in LTE-Advanced HetNet Deployments

    DEFF Research Database (Denmark)

    Gimenez, Lucas Chavarria; Kovacs, Istvan Z.; Wigard, Jeroen;

    2015-01-01

    The objective of this paper is to propose traffic steering solutions that aim at optimizing the end-user throughput. Two different implementations of an active mode throughput-based traffic steering algorithm for Heterogeneous Networks (HetNet) are introduced. One that always forces handover...... slightly lower traffic steering gains at a considerably lower cost in terms of number of handovers. The gain in terms of increased average session throughput for the second option equals 32% at low-load, 18% at medium-load, and 7% at high-load conditions. The gain in the fifth percentile user session...

  12. Optimal traffic light control method for a single intersection based on hybrid systems

    Institute of Scientific and Technical Information of China (English)

    赵晓华; 陈阳舟; 崔平远

    2003-01-01

    A single intersection of two phases is selected as a model to put forward a new optimal time-planning scheme for traffic light based on the model of hybrid automata for single intersection. A method of optimization is proposed for hybrid systems, and the average queue length over all queues is used as an objective function to find an optimal switching scheme for traffic light. It is illustrated that traffic light control for single intersection is a typical hybrid system, and the optimal planning-time scheme can be obtained using the optimal hybrid systems control based on the two stages method.

  13. Microscale traffic simulation and emission estimation in a heavily trafficked roundabout in Madrid (Spain).

    Science.gov (United States)

    Quaassdorff, Christina; Borge, Rafael; Pérez, Javier; Lumbreras, Julio; de la Paz, David; de Andrés, Juan Manuel

    2016-10-01

    This paper presents the evaluation of emissions from vehicle operations in a domain of 300m×300m covering a complex urban roundabout with high traffic density in Madrid. Micro-level simulation was successfully applied to estimate the emissions on a scale of meters. Two programs were used: i) VISSIM to simulate the traffic on the square and to compute velocity-time profiles; and ii) VERSIT+micro through ENVIVER that uses VISSIM outputs to compute the related emissions at vehicle level. Data collection was achieved by a measurement campaign obtaining empirical data of vehicle flows and traffic intensities. Twelve simulations of different traffic situations (scenarios) were conducted, representing different hours from several days in a week and the corresponding NOX and PM10 emissions were estimated. The results show a general reduction on average speeds for higher intensities due to braking-acceleration patterns that contribute to increase the average emission factor and, therefore, the total emissions in the domain, especially on weekdays. The emissions are clearly related to traffic volume, although maximum emission scenario does not correspond to the highest traffic intensity due to congestion and variations in fleet composition throughout the day. These results evidence the potential that local measures aimed at alleviating congestion may have in urban areas to reduce emissions. In general, scenario-averaged emission factors estimated with the VISSIM-VERSIT+micro modelling system fitted well those from the average-speed model COPERT, used as a preliminary validation of the results. The largest deviations between these two models occur in those scenarios with more congestion. The design and resolution of the microscale modelling system allow to reflect the impact of actual traffic conditions on driving patterns and related emissions, making it useful for the design of mitigation measures for specific traffic hot-spots.

  14. Performance of an Automated-Mixed-Traffic-Vehicle /AMTV/ System. [urban people mover

    Science.gov (United States)

    Peng, T. K. C.; Chon, K.

    1978-01-01

    This study analyzes the operation and evaluates the expected performance of a proposed automatic guideway transit system which uses low-speed Automated Mixed Traffic Vehicles (AMTV's). Vehicle scheduling and headway control policies are evaluated with a transit system simulation model. The effect of mixed-traffic interference on the average vehicle speed is examined with a vehicle-pedestrian interface model. Control parameters regulating vehicle speed are evaluated for safe stopping and passenger comfort.

  15. Benzene from Traffic

    DEFF Research Database (Denmark)

    Palmgren, F.; Berkowicz, R.; Skov, H.;

    The measurements of benzene showed very clear decreasing trends in the air concentrations and the emissions since 1994. At the same time the measurements of CO and NOx also showed a decreasing trend, but not so strong as for benzene. The general decreasing trend is explained by the increasing...... number of petrol vehicles with three way catalysts, 60-70% in 1999. The very steep decreasing trend for benzene at the beginning of the period from 1994 was explained by the combination of more catalyst vehicles and reduced benzene content in Danish petrol. The total amount of aromatics in petrol......, including toluene, increased only weakly. The analyses of air concentrations were confirmed by analyses of petrol sold in Denmark. The concentration of benzene at Jagtvej in Copenhagen is still in 1998 above the expected new EU limit value, 5 µg/m3 as annual average. However, the reduced content of benzene...

  16. Study and Simulation of Traffic Behavior in Cellular Network

    Science.gov (United States)

    Madhup, D. K.; Shrestha, C. L.; Sharma, R. K.

    2007-07-01

    Cellular radio systems accommodate a large number of users with a limited radio spectrum. The concept of trunking allows a large number of users to share the relatively small number of channels in a cell by providing access to each user, on demand, from a pool of available channels. Traffic engineering deals with provisioning of communication circuits in a given area for a number of subscribers with a required grade of service. Traffic in any cell depends upon the number of users, the average request rate and average call duration. Certain number of channels is required for the required GOS. To design an optimum capacity cellular system, traffic behavior on that system is important. The number of channel required can be estimated by using Erlang formula and Erlang table. Erlang table is not always useful to calculate the probability of blocking in various complex scenarios such as channel borrowing strategies. When the total number of channel available in a given cell are divided to serve partly for newly generated calls and partly for handover calls, and if they use dynamic channel assignment strategies like channel borrowing, then the probability of blocking can't be calculated from Erlang table. Simulation model of the behavior help us to determine the blocking and the channel utilization while using various channel assignment strategies. The title "Study and Simulation of Traffic Behavior in Cellular Network" entail the study of the blocking probability of traffic in cellular network for static channel assignment strategies and dynamic channel borrowing strategies through MATLAB programming language and graphic user interface (GUI). The result shows that the dynamic scheme can perform better than static maximizing the overall utilization of the circuits and minimizing the overall blocking.

  17. Fuzzy Multiobjective Traffic Light Signal Optimization

    Directory of Open Access Journals (Sweden)

    N. Shahsavari Pour

    2013-01-01

    Full Text Available Traffic congestion is a major concern for many cities throughout the world. In a general traffic light controller, the traffic lights change at a constant cycle time. Hence it does not provide an optimal solution. Many traffic light controllers in current use are based on the “time-of-the-day” scheme, which use a limited number of predetermined traffic light patterns and implement these patterns depending upon the time of the day. These automated systems do not provide an optimal control for fluctuating traffic volumes. In this paper, the fuzzy traffic light controller is used to optimize the control of fluctuating traffic volumes such as oversaturated or unusual load conditions. The problem is solved by genetic algorithm, and a new defuzzification method is introduced. The performance of the new defuzzification method (NDM is compared with the centroid point defuzzification method (CPDM by using ANOVA. Finally, an illustrative example is presented to show the competency of proposed algorithm.

  18. Wireless traffic steering for green cellular networks

    CERN Document Server

    Zhang, Shan; Zhou, Sheng; Niu, Zhisheng; Shen, Xuemin (Sherman)

    2016-01-01

    This book introduces wireless traffic steering as a paradigm to realize green communication in multi-tier heterogeneous cellular networks. By matching network resources and dynamic mobile traffic demand, traffic steering helps to reduce on-grid power consumption with on-demand services provided. This book reviews existing solutions from the perspectives of energy consumption reduction and renewable energy harvesting. Specifically, it explains how traffic steering can improve energy efficiency through intelligent traffic-resource matching. Several promising traffic steering approaches for dynamic network planning and renewable energy demand-supply balancing are discussed. This book presents an energy-aware traffic steering method for networks with energy harvesting, which optimizes the traffic allocated to each cell based on the renewable energy status. Renewable energy demand-supply balancing is a key factor in energy dynamics, aimed at enhancing renewable energy sustainability to reduce on-grid energy consum...

  19. Highway and traffic engineering in developing countries

    DEFF Research Database (Denmark)

    1996-01-01

    Describes road and traffic engineering methods and problems in developing countries as opposed to similar problems in industrialized countries......Describes road and traffic engineering methods and problems in developing countries as opposed to similar problems in industrialized countries...

  20. Allegheny County Jail Daily Census

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — A daily census of the inmates at the Allegheny County Jail (ACJ). Includes gender, race, age at booking, and current age. The records for each month contain a...

  1. The patient with daily headaches.

    Science.gov (United States)

    Maizels, Morris

    2004-12-15

    The term "chronic daily headache" (CDH) describes a variety of headache types, of which chronic migraine is the most common. Daily headaches often are disabling and may be challenging to diagnose and treat. Medication overuse, or drug rebound headache, is the most treatable cause of refractory daily headache. A pathologic underlying cause should be considered in patients with recent-onset daily headache, a change from a previous headache pattern, or associated neurologic or systemic symptoms. Treatment of CDH focuses on reduction of headache triggers and use of preventive medication, most commonly anti-depressants, antiepileptic drugs, and beta blockers. Medication overuse must be treated with discontinuation of symptomatic medicines, a transitional therapy, and long-term prophylaxis. Anxiety and depression are common in patients with CDH and should be identified and treated. Although the condition is challenging, appropriate treatment of patients with CDH can bring about significant improvement in the patient's quality-of-life.

  2. Lightship Daily Observations - NARA Collection

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Observations taken on board lightships along the United States coasts from 1893 - 1943. Generally 4-6 observations daily. Also includes deck logs, which give...

  3. Analysis of Traffic Conditions in Urban Region Based on Data from Fixed Detectors

    Directory of Open Access Journals (Sweden)

    Shidong Liang

    2015-01-01

    Full Text Available To evaluate traffic conditions in an urban region, the average travel speed in the street network and the average traffic flow per lane are selected as indexes. The results for identifying traffic conditions are obtained using macroscopic fundamental diagram. Because of the difficulty of collecting the traffic parameter of travel speed from widely distributed fixed detectors directly, in this paper, the relationship between average travel speed and queue lengths at signalized intersections within the urban area is established based on an equivalent assumption. Finally, the average travel speed estimation model proposed in this paper is tested with microscopic simulation platform, and the results showed that the average travel speed estimation model performed well with satisfactory accuracy. In addition, the best performance of the network efficiency can be identified based on the reflections of macroscopic fundamental diagram, and the evaluation system is simple enough for application in engineering. Therefore, the result is instructive both for generating traffic control strategies and for making route choices.

  4. Comparison of Pinavia Interchange Vs Interchange's All Directional and Nano of Traffic Operation and Safety with Traffic simulation

    Directory of Open Access Journals (Sweden)

    Abolfazl samadi Heidar Abadi

    2016-06-01

    Full Text Available in this study, one of the newest types of interchange, which has recently attracted the attention of researchers and designers, i.e. Pinnavia and one of most recent interchange, i.e. the nano interchange and one of the world's most popular interchange, ie the all directional interchange are thoroughly investigated and the reasons for using it will be expressed. In this research, replacement of the Pinnavia interchange with the nano interchange, the all directional interchange with the input vehicle volume of 10000 in an hour and speeds of 70 and 90 km/sec, 2 percent of 10% and 20% heavy vehicles, two turnover ratio of 70 to 30 of left heavy, direct-equal of 50 to 50, under the number of 24 scenarios have been studied using a microscopic simulation by the AIMSUN software. Traffic operation analysis was conducted for the whole interchange. Moreover, parameters of Speed, Delay Time and, Density were compared. SSAM is an application that evaluates the traffic safety by the traffic noise and processing of vehicles routing. Interchange occurs when two road users are in collision position with no escape possibility. The safety estimation has been carried out for the whole interchange with the traffic volume of 10000 vph in highway, ramp volume of 1600 and 1000 vehicles in houre and 20% heavy vehicles which is one f the worst scenario cases. The results of this research reveal the better performance of the nano interchange in most traffic parameters such as, delay time,density and average speed. In terms of safety, the pinnavia interchange operation is better than the performance of the nano and All-directional Interchanges. Moreover, speed increment made a better traffic performance in the pinnavia interchange. In other words, operation of the the pinnavia interchange is better than the performance of the nano and All-directional Interchanges in the speed of 90 Km/h.

  5. Poisson vs. Long-Tailed Internet traffic

    OpenAIRE

    2005-01-01

    In this thesis, we reexamine the long discussion on which model is suitable for studying Internet traffic: Poisson or Long-tailed Internet traffic. Poisson model, adapted from telephone network, has been used since the beginning of World Wide Web, while long-tailed distribution gradually takes over with believable evidence. Instead of using Superposition of Point Processes to explain why traffic that is not Poisson tends towards Poisson traffic as the load increases, as it is recent...

  6. Vehicle Traffic Congestion Estimation Based on RFID

    OpenAIRE

    Al-Naima, Fawzi M.; Hamd, Hassan A.

    2012-01-01

    Due to the proliferation in the number of vehicles on the road, traffic problems are bound to exist. Therefore, the use of Intelligent Transportation Systems (ITS) has become mandatory for obtaining traffic information from roads. Radio Frequency Identification (RFID) technology has been used to obtain vehicles’ IDs (tag ID) from RFID readers and to collect traffic information in real‐time. This paper proposes a simulation system for the Vehicle Traffic Congestion Estimation (VTCE) based on R...

  7. Rethinking Traffic Management: Design of Optimizable Networks

    Science.gov (United States)

    2008-06-01

    traffic traverses each path in a network. On the Internet today, end hosts run congestion control to adapt sending rates, routers route traffic on...congestion control to adapt sending rates, routers route traffic on shortest paths based on link weights, and operators tune link weights to direct traffic...Chaintreau and Christophe Diot for giving me the opportunity to intern at Thomson Research Labs in Paris. Thanks to all the interns there for v making it

  8. Highway traffic model-based density estimation

    OpenAIRE

    Morarescu, Irinel - Constantin; CANUDAS DE WIT, Carlos

    2011-01-01

    International audience; The travel time spent in traffic networks is one of the main concerns of the societies in developed countries. A major requirement for providing traffic control and services is the continuous prediction, for several minutes into the future. This paper focuses on an important ingredient necessary for the traffic forecasting which is the real-time traffic state estimation using only a limited amount of data. Simulation results illustrate the performances of the proposed ...

  9. Probabilistic description of traffic breakdowns.

    Science.gov (United States)

    Kühne, Reinhart; Mahnke, Reinhard; Lubashevsky, Ihor; Kaupuzs, Jevgenijs

    2002-06-01

    We analyze the characteristic features of traffic breakdown. To describe this phenomenon we apply the probabilistic model regarding the jam emergence as the formation of a large car cluster on a highway. In these terms, the breakdown occurs through the formation of a certain critical nucleus in the metastable vehicle flow, which enables us to confine ourselves to one cluster model. We assume that, first, the growth of the car cluster is governed by attachment of cars to the cluster whose rate is mainly determined by the mean headway distance between the car in the vehicle flow and, maybe, also by the headway distance in the cluster. Second, the cluster dissolution is determined by the car escape from the cluster whose rate depends on the cluster size directly. The latter is justified using the available experimental data for the correlation properties of the synchronized mode. We write the appropriate master equation converted then into the Fokker-Planck equation for the cluster distribution function and analyze the formation of the critical car cluster due to the climb over a certain potential barrier. The further cluster growth irreversibly causes jam formation. Numerical estimates of the obtained characteristics and the experimental data of the traffic breakdown are compared. In particular, we draw a conclusion that the characteristic intrinsic time scale of the breakdown phenomenon should be about 1 min and explain the case why the traffic volume interval inside which traffic breakdown is observed is sufficiently wide.

  10. The role of traffic rules.

    NARCIS (Netherlands)

    Noordzij, P.C.

    1988-01-01

    Experienced road users seem to have their own set of traffic rules (including rules about when to violate the official rules). The number of violations is enormous, causing great concern for the authorities. The situation could be improved by separating a set of rules with the aim of deterring road

  11. Traffic Congestion and Congestion Pricing

    OpenAIRE

    Verhoef, E.T.; Lindsey, C.R.

    2000-01-01

    For several decades growth of traffic volumes has outstrippedinvestments inroad infrastructure. The result has been a relentless increase intrafficcongestion. This paper reviews the economic principles behindcongestionpricing in static and dynamic settings, which derive from thebenefits ofcharging travellers for the externalities they create. Specialattention ispaid to various complications that make simple textbook congestionpricingmodels of limited relevance, and dictate that congestion pri...

  12. Learning to Detect Traffic Signs

    DEFF Research Database (Denmark)

    Møgelmose, Andreas; Trivedi, Mohan M.; Moeslund, Thomas B.

    2012-01-01

    This study compares the performance of sign detection based on synthetic training data to the performance of detection based on real-world training images. Viola-Jones detectors are created for 4 different traffic signs with both synthetic and real data, and varying numbers of training samples. T...

  13. House attenuation of aircraft and street traffic noise in relation to annoyance: A pilot study

    Science.gov (United States)

    Kryter, Karl D.

    2001-05-01

    House barrier sound attenuation was measured as differences between the levels of street traffic and aircraft noise found outdoors near the front (street facing) and rear façades, and in rooms of two one-story houses. Also, attenuation of street traffic and aircraft noise between the front and rear façades of similar one-story houses was calculated in accordance with acoustical models. Findings: (1) relative to levels measured near the front façade, street traffic noise near the rear façade, and in rooms inside the houses, was, on average, 9 max dB and 8 SEL dB more attenuated than was aircraft noise. (2) When attenuation of street traffic noise was measured relative to its level near the front façade, and attenuation for aircraft noise was measured relative to its level near the rear façade, street traffic noise was, on average, 7 max dB and 6 SEL dB more attenuated than aircraft noise. (3) Calculated barrier attenuation of street traffic noise was, on average, 1.3 max dB less than measured; calculated barrier attenuation of aircraft noise differed from measured by ~0.4 max dB. Implications of the findings for guidelines for assessing impact of these noises on communities and land-use zoning are discussed.

  14. Computational intelligence for traffic and mobility

    CERN Document Server

    Wang, Wuhong

    2012-01-01

    This book presents the new development of computation intelligence for traffic, transportation and mobility, the main contents include traffic safety, mobility analysis, intelligent transportation system, smart vehicle, transportation behavior, driver modeling and assistance, transportation risk analysis and reliability system analysis, vehicle operation and active safety, urban traffic management and planning.

  15. Prediction of Railway Passenger Traffic Volume

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The current situation of the railway passenger traffic (RPT) andthe traffic marketing is analyzed. The grey model theory is adopted to establish a prediction model for the railway passenger traffic volume (RPTV). The RPTV from 2001 to 2005 is predicted with the proposed model, and a few suggestions are put forward.

  16. Capturing Internet Traffic Dynamics through Graph Distances

    NARCIS (Netherlands)

    Uhlig, S.; Fu, B.; Jamakovic, A.

    2009-01-01

    Studies of the Internet have typically focused either on the routing system, i.e. the paths chosen to reach a given destination, or on the evolution of traffic on a physical link. In this paper, we combine routing and traffic, and study for the first time the evolution of the traffic on the Internet

  17. Light signals for road traffic control.

    NARCIS (Netherlands)

    Schreuder, D.A.

    1981-01-01

    Signals for road traffic control are a major constituent of the modern traffic scene, particularly in built-up areas. A vast amount of research has been executed in the last two decennia, resulting in a fairly generally accepted view on what the requirements for effective traffic lights are. For the

  18. Disseminating Traffic Information in Vehicular Networks

    Directory of Open Access Journals (Sweden)

    Muhammad Alyas Shahid

    2015-11-01

    Full Text Available In this paper Wifi based system is described for disseminating traffic information in vehicular networks. Basic aim of this approach is to distribute information regarding the traffic conditions such as traffic congestions or safety warnings to vehicles in an effective way.

  19. 15 CFR 265.22 - Bicycle traffic.

    Science.gov (United States)

    2010-01-01

    ... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Bicycle traffic. 265.22 Section 265.22... Bicycle traffic. No person shall ride a bicycle other than in a manner exercising due caution for pedestrian and other traffic. No person shall ride a bicycle on sidewalks or inside any building, nor...

  20. 30 CFR 56.9100 - Traffic control.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Traffic control. 56.9100 Section 56.9100 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Dumping Traffic Safety § 56.9100 Traffic control. To provide for the safe movement of...

  1. Some random models in traffic science

    Energy Technology Data Exchange (ETDEWEB)

    Hjorth, U.

    1996-06-01

    We give an overview of stochastic models for the following traffic phenomena. Models for traffic flow including gaps and capacities for lanes, crossings and roundabouts. Models for wanted and achieved speed distributions. Mode selection models including dispersed equilibrium models and traffic accident models. Also some statistical questions are discussed. 60 refs, 1 tab

  2. Empirical analysis of heterogeneous traffic flow

    NARCIS (Netherlands)

    Ambarwati, L.; Pel, A.J.; Verhaeghe, R.J.; Van Arem, B.

    2013-01-01

    Traffic flow in many developing countries is strongly mixed comprising vehicle types, such as motorcycles, cars, (mini) buses, and trucks; furthermore, traffic flow typically exhibits free inter-lane exchanges. This phenomenon causes a complex vehicle interaction, rendering most existing traffic flo

  3. Models for Predictive Railway Traffic Management

    NARCIS (Netherlands)

    Kecman, P.

    2014-01-01

    The potential growth in transport demand in the next decade and beyond requires a change from reactive to proactive traffic control to maintain and improve the reliability of railway traffic. In order to enable an anticipative approach to traffic management, it is necessary to develop the tools for

  4. NEW POSSIBILITIES OF RAILWAY TRAFFIC CONTROL SYSTEMS

    Directory of Open Access Journals (Sweden)

    Lionginas LIUDVINAVIČIUS

    2016-06-01

    Full Text Available This article analyses the train traffic control systems in 1435 mm and 1520 mm gauge railways. The article analyses the aspects of train traffic control and locomotive energy saving by using the coordinates of track profile change that have been received from GPS. In the article, achievements of Lithuanian railways (LG in the area of train traffic control optimisation are presented.

  5. Traffic Measurement for Traffic Engineering in IP/MPLS Based Telecom Core Networks

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Telecommunication networks will become IP-based networks with all voice, data and multimedia traffic carried as packets with appropriate quality and class of service for each traffic type. It is very important for service provider to apply Traffic Engineering (TE) with the dramatic growth of networks traffic. In this paper, we discuss traffic engineering based on IP/MPLS and emphasize traffic measurement in telecom core networks. We specify the technology and scientific principles of the measurement, modeling, characterization, and the traffic flow matrix. The paper concludes with a preliminary analysis of TE measurement and a discussion about the development of TE measurement.

  6. A traffic model of optical networks based on time-space complexity and traffic grooming

    Institute of Scientific and Technical Information of China (English)

    Zhao Yongli; Zhang Jie; Han Dahai; Wang Lei; Chen Xiuzhong; Gu Wanyi

    2009-01-01

    This paper researched the traffic of optical networks in time-space complexity, proposed a novel traffic model for complex optical networks based on traffic grooming, designed a traffic generator GTS (generator based on time and space) with "centralized + distributed" idea, and then made a simulation in C language. Experiments results show that GTS can produce the virtual network topology which can change dynamically with the characteristic of scaling-free network. GTS can also groom the different traffic and trigger them under real-time or scheduling mechanisms, generating different optical connections. This traffic model is convenient for the simulation of optical networks considering the traffic complexity.

  7. Traffic fatalities and economic growth.

    Science.gov (United States)

    Kopits, Elizabeth; Cropper, Maureen

    2005-01-01

    This paper examines the relationship between traffic fatality risk and per capita income and uses it to forecast traffic fatalities by geographic region. Equations for the road death rate (fatalities/population) and its components--the rate of motorization (vehicles/population) and fatalities per vehicle (F/V)--are estimated using panel data from 1963 to 1999 for 88 countries. The natural logarithm of F/P, V/P, and F/V are expressed as spline (piecewise linear) functions of the logarithm of real per capita GDP (measured in 1985 international prices). Region-specific time trends during the period 1963-1999 are modeled in linear and log-linear form. These models are used to project traffic fatalities and the stock of motor vehicles to 2020. The per capita income at which traffic fatality risk (fatalities/population) begins to decline is 8600 US dollars (1985 international dollars) when separate time trends are used for each geographic region. This turning point is driven by the rate of decline in fatalities/vehicles as income rises since vehicles/population, while increasing with income at a decreasing rate, never declines with economic growth. Projections of future traffic fatalities suggest that the global road death toll will grow by approximately 66% over the next twenty years. This number, however, reflects divergent rates of change in different parts of the world: a decline in fatalities in high-income countries of approximately 28% versus an increase in fatalities of almost 92% in China and 147% in India. The road death rate is projected to rise to approximately 2 per 10,000 persons in developing countries by 2020, while it will fall to less than 1 per 10,000 in high-income countries.

  8. AMSR-E/Aqua Daily L3 6.25 km 89 GHz Brightness Temperature (Tb) Polar Grids V002

    Data.gov (United States)

    National Aeronautics and Space Administration — The AMSR-E/Aqua Level-3 6.25 km daily sea ice product includes 89.0 GHz brightness temperature averages (daily, ascending, and descending) on a 6.25 km polar...

  9. Road traffic administration and management in the third world mega-city: Lagos, Nigeria

    Directory of Open Access Journals (Sweden)

    R.A. Asiyanbola

    2012-09-01

    Full Text Available Observation from the literature shows that a city can only be as big as its transportation facilities can enable its people goes about their businesses, move and distribute their goods and services. In spite of these positive aspects of urban transportation system on one side of the coin, the other side of the coin reflects its negative impact that relate to traffic management and administration and road safety. The daily movement of people and freights within and outside the mega-city of LAGOS is becoming more difficult and complex. This is reflected in the increasing bumper-to-bumper traffic being experienced in the mega-city of Lagos during 6.30 am – 11.30am morning peak hours and (3.00pm – 7.30 pm evening peak hours. It now seems that traffic congestions are becoming forcefully acceptable excuses for workers being late to work in Lagos metropolis. One approach at solving this problem adopted by the Lagos State Government is traffic management through the establishment of the Lagos State Traffic Management Authority (LASTMA. Traffic management could be regarded as a systematic and sustained effort on directing and controlling all traffics on our roads to make them free from negative effects of the transport system. The aim of this research work was to assess the impact of the Lagos State Traffic Management Authority (LASTMA with particular reference on the efforts to reduce road traffic problems. Both secondary and primary data sources that were collected in 2008 were used in the study. Policy implications of the findings are discussed in the paper.

  10. Asymptotic dynamics of closed-boundary vehicular traffic

    CERN Document Server

    Lee, Chi-Lun

    2010-01-01

    We study the dynamics of vehicular traffic in a loop using a car-following model with the consideration of volume exclusions. In particular, we solve the steady state for the single-cluster case and derive fundamental diagrams, exhibiting two branches representative of entering and leaving the jam, respectively. By simulations we also observe that the speed average over all vehicles reaches the same constant at the steady states, regardless of the final clustering state. The autocorrelation functions for the overall speed average and single vehicle speed are investigated, each revealing a robust time scale. The effects of noises in vehicular acceleration are discussed.

  11. Detecting traffic hot spots using vehicle tracking data

    Science.gov (United States)

    Xu, Zhimin; Lin, Zhiyong; Zhou, Cheng; Huang, Changqing

    2016-03-01

    Vehicle tracking data for thousands of urban vehicles and the availability of digital map provide urban planners unprecedented opportunities for better understanding urban transportation. In this paper, we aim to detect traffic hot spots on urban road networks using vehicle tracking data. Our approach first proposes an integrated map-matching algorithm based on the road buffer and vehicle driving direction, to find out which road segment the vehicle is travelling on. Then, we estimate travel speed by calculating the average the speed of every vehicle on a certain road segment, which indicates traffic status, and create the spatial weights matrices based on the connectivity of road segments, which expresses the spatial dependence between each road segment. Finally, the measure of global and local spatial autocorrelation is used to evaluate the spatial distribution of the traffic condition and reveal the traffic hot spots on the road networks. Experiments based on the taxi tracking data and urban road network data from Wuhan have been performed to validate the detection effectiveness.

  12. Towards a macroscopic modeling of the complexity in traffic flow.

    Science.gov (United States)

    Rosswog, Stephan; Wagner, Peter

    2002-03-01

    Based on the assumption of a safe velocity U(e)(rho) depending on the vehicle density rho, a macroscopic model for traffic flow is presented that extends the model of the Kühne-Kerner-Konhäuser by an interaction term containing the second derivative of U(e)(rho). We explore two qualitatively different forms of U(e): a conventional Fermi-type function and, motivated by recent experimental findings, a function that exhibits a plateau at intermediate densities, i.e., in this density regime the exact distance to the car ahead is only of minor importance. To solve the fluid-like equations a Lagrangian particle scheme is developed. The suggested model shows a much richer dynamical behavior than the usual fluid-like models. A large variety of encountered effects is known from traffic observations, many of which are usually assigned to the elusive state of "synchronized flow." Furthermore, the model displays alternating regimes of stability and instability at intermediate densities. It can explain data scatter in the fundamental diagram and complicated jam patterns. Within this model, a consistent interpretation of the emergence of very different traffic phenomena is offered: they are determined by the velocity relaxation time, i.e., the time needed to relax towards U(e)(rho). This relaxation time is a measure of the average acceleration capability and can be attributed to the composition (e.g., the percentage of trucks) of the traffic flow.

  13. Analysis of sequencing and scheduling methods for arrival traffic

    Science.gov (United States)

    Neuman, Frank; Erzberger, Heinz

    1990-01-01

    The air traffic control subsystem that performs scheduling is discussed. The function of the scheduling algorithms is to plan automatically the most efficient landing order and to assign optimally spaced landing times to all arrivals. Several important scheduling algorithms are described and the statistical performance of the scheduling algorithms is examined. Scheduling brings order to an arrival sequence for aircraft. First-come-first-served scheduling (FCFS) establishes a fair order, based on estimated times of arrival, and determines proper separations. Because of the randomness of the traffic, gaps will remain in the scheduled sequence of aircraft. These gaps are filled, or partially filled, by time-advancing the leading aircraft after a gap while still preserving the FCFS order. Tightly scheduled groups of aircraft remain with a mix of heavy and large aircraft. Separation requirements differ for different types of aircraft trailing each other. Advantage is taken of this fact through mild reordering of the traffic, thus shortening the groups and reducing average delays. Actual delays for different samples with the same statistical parameters vary widely, especially for heavy traffic.

  14. Non-stationarity in daily and sub-daily intense rainfall – Part 1: Sydney, Australia

    Directory of Open Access Journals (Sweden)

    D. Jakob

    2011-08-01

    Full Text Available This study was driven by a need to clarify how variations in climate might affect intense rainfall and the potential for flooding. Sub-daily durations are of particular interest for urban applications. Worldwide, few such observation-based studies exist, which is mainly due to limitations in data. While there are still large discrepancies between precipitation data sets from observations and models, both show that there is a tendency for moist regions to become wetter and for dry regions to become drier. However, changes in extreme conditions may show the opposite sign to those in average conditions. Where changes in observed intense precipitation have been studied, this has typically been for daily durations or longer.

    The purpose of this two-part study is to examine daily and sub-daily rainfall extremes for evidence of non-stationarity. Here the problem was addressed by supplementing one long record (Part 1 by a set of shorter records for a 30-yr concurrent period (Part 2. Variations in frequency and magnitude of rainfall extremes across durations from 6 min to 72 h were assessed using data from sites in the south-east of Australia. For the analyses presented in this paper, a peaks-over-threshold approach was chosen since it allows investigating changes in frequency as well as magnitude. Non-parametric approaches were used to assess changes in frequency, magnitude, and quantile estimates as well as the statistical significance of changes for one station (Sydney Observatory Hill for the period 1921 to 2005. Deviations from the long-term average vary with season, duration, and threshold. The effects of climate variations are most readily detected for the highest thresholds. Deviations from the long-term average tend to be larger for frequencies than for magnitudes, and changes in frequency and magnitude may have opposite signs.

    Investigations presented in this paper show that variations in frequency and magnitude of events at

  15. Traffic Modeling in WCDMA System Level Simulations

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Traffic modeling is a crucial element in WCDMA system level simulations. A clear understanding of the nature of traffic in the WCDMA system and subsequent selection of an appropriate random traffic model are critical to the success of the modeling enterprise. The resultant performances will evidently be of a function that our design has been well adapted to the traffic, channel and user mobility models, and these models are also accurate. In this article, our attention will be focused on modeling voice and WWW data traffic with the SBBP model and Victor model respectively.

  16. Characterization and Modeling of Network Traffic

    DEFF Research Database (Denmark)

    Shawky, Ahmed; Bergheim, Hans; Ragnarsson, Olafur

    2011-01-01

    This paper attempts to characterize and model backbone network traffic, using a small number of statistics. In order to reduce cost and processing power associated with traffic analysis. The parameters affecting the behaviour of network traffic are investigated and the choice is that inter......-arrival time, IP addresses, port numbers and transport protocol are the only necessary parameters to model network traffic behaviour. In order to recreate this behaviour, a complex model is needed which is able to recreate traffic behaviour based on a set of statistics calculated from the parameters values...

  17. Estimating the real world daily usage and cost for exenatide twice daily and liraglutide in Germany, the Netherlands, and the UK based on volumes dispensed by pharmacies

    Directory of Open Access Journals (Sweden)

    McDonell AL

    2015-01-01

    Full Text Available Amanda L McDonell,1 Urpo Kiiskinen,2 Danielle C Zammit,3 Robert W Kotchie,1 Per-Olof Thuresson,3 Claudia Nicolay,4 Thomas Haslam,1 Michiel Bruinsma,5 Anne-Jeanine Janszen-Van Oosterhout,6 Thorsten Otto41IMS Health, London, UK; 2Eli Lilly and Company, Helsinki, Finland; 3IMS Health, Basel, Switzerland; 4Eli Lilly and Company, Bad Homburg, Germany; 5IMS Health, Rotterdam, the Netherlands; 6Eli Lilly Nederland, Houten, the NetherlandsBackground: Glucagon-like peptide-1 (GLP-1 receptor agonists are indicated for improvement of glycemic control in adults with type 2 diabetes. Cost is one aspect of treatment to be considered, in addition to clinical benefits, when selecting optimal therapy for a patient. The objective of this study was to estimate the average dose usage and real world daily cost of the GLP-1 receptor agonists, exenatide twice daily and liraglutide once daily, in Germany, the Netherlands, and the UK.Methods: Administrative databases were used to source the data from longitudinal records of dispensed prescriptions. Data were extracted from the IMS Longitudinal Prescription database which captures details of prescriptions dispensed in pharmacies. Information on the dispensed quantity of each product was used to estimate average daily usage per patient. Daily dose usage was multiplied by the public price per unit to estimate daily cost.Results: The dispensed volume in Germany corresponded to a mean dispensed daily dose of 16.81 µg for exenatide twice daily and 1.37 mg for liraglutide (mean daily cost €4.02 and €4.54, respectively. In the Netherlands, average dispensed daily doses of 17.07 µg and 1.49 mg were observed for exenatide twice daily and liraglutide (mean daily cost €3.05 and €3.97, respectively. In the UK, the mean dispensed volume corresponded to a daily usage of 20.49 µg for exenatide twice daily and 1.50 mg for liraglutide (mean daily cost £2.53 and £3.28, respectively.Conclusion: Estimates of average daily

  18. Revolutionizing Technology Prioritizing Emergency Vehicles in Traffic

    Directory of Open Access Journals (Sweden)

    B. Ramya Sundaram

    2014-08-01

    Full Text Available The following study brings to the fore a technology exclusively engineered to eradicate the snags and inadequacies persisting in the existing system of traffic control and thus aims to provide a sophisticated operation and uninterrupted course for the emergency vehicles. The traffic in Indian roads has shown a tremendous rise over the years and the conventional pre-timed traffic signals and frequent traffic congestions, delaying the road commuters, have led to outrage and chaos on several occasions. This traffic management system has proved a nuisance for the effective operation of emergency vehicles, with the public adding to the woes, as each driver races along with the signal, unmindful of the emergency vehicles. A life threatening scenario ensues when emergency vehicles get blocked by the traffic, due to inefficient traffic management system and subsequently these emergency vehicles get delayed. The existing system requires manual interruption to guide other vehicles when an emergency vehicle passes through traffic junctions. It is therefore essential to implement a self-regulating and automated system in the traffic signals to facilitate smooth movement of emergency vehicles without posing a danger to other vehicles. The innovative traffic control system devised by us provides a truly dependable alternative to monitoring traffic flow when emergency vehicles pass by.

  19. The car following model considering traffic jerk

    Science.gov (United States)

    Ge, Hong-Xia; Zheng, Peng-jun; Wang, Wei; Cheng, Rong-Jun

    2015-09-01

    Based on optimal velocity car following model, a new model considering traffic jerk is proposed to describe the jamming transition in traffic flow on a highway. Traffic jerk means the sudden braking and acceleration of vehicles, which has a significant impact on traffic movement. The nature of the model is researched by using linear and nonlinear analysis method. A thermodynamic theory is formulated to describe the phase transition and critical phenomenon in traffic flow. The time-dependent Ginzburg-Landau (TDGL) equation and the modified Korteweg-de Vries (mKdV) equation are derived to describe the traffic flow near the critical point and the traffic jam. In addition, the connection between the TDGL and the mKdV equations are also given.

  20. TRAFFIC EMISSION TRANSPORTATION IN STREET CANYONS

    Institute of Scientific and Technical Information of China (English)

    XIE Xiao-min; WANG Jia-song; HUANG Zhen

    2009-01-01

    Spatial distributions of traffic-related pollutants in street canyons were investigated by field measurements and Computational Fluid Dynamics(CFD).Two typical street canyons were selected for field monitoring,and a three-dimensional numerical model was built based on Reynolds-averaged Navier-Stokes equations equipped with the standard k-ε turbulence models for CFD simulations.The study shows that the pollutant concentrations of vehicle emission correlate well with the traffic volume variation,wind direction and wind speed.The wind direction and speed at the roof level determine overwhellmingly the flow field and the distributions of pollutant concentrations in the street canyon.When the wind speed is equal to zero,the pollutant concentrations on the breath height of the both sides of the street canyon are almost the same.When the wind direction is perpendicular to the street,one main vortex is formed with a shape depending on the building structure on both sides of the street,the pollutant is accumulated on the leeward side,and the pollutant concentrations at the breath height on the leeward side are 2 to 3 times as those at the breath height on the windward side.If the wind direction makes some angles with the street canyon,the pollutant concentration will be higher on the leeward side because one main vortex will also be formed in the vertical section of the canyon by the perpendicular component of the wind.But pollutant concentrations decrease in the canyon because pollutants are dispersed along the axis of the street.Pollutants at different heights of the vertical section decrease with height,i.e.there are concentration gradients in the vertical section,and the pollutant concentrations on the leeward side of the upstream building are much higher than those on the windward side of the downstream building.

  1. Analyzing lead concentration in the sycamore tree species in high- and low-traffic areas of Rasht, Iran.

    Science.gov (United States)

    Hashemi, Seyed Armin; Alinejad, Farzaneh; FallahChay, Mozaffar

    2015-06-01

    Important heavy metals such as lead and cadmium are part of the pollutants produced by cars and are spread in the urban environment by traffic flow. In order to study the amount of contamination in the trees along the streets and to determine the traffic parameters that affect the lead content in sycamore leaves in Rasht, four stations on the margins of the city streets were selected for this case study in terms of traffic volume (low or high). Traffic parameters including three high-traffic stations considering daily and monthly traffic volumes and one low-traffic station were selected. First, 32 sycamore bases were randomly chosen at the intervals of 10-15 m from the whole range of tree canopy in order to determine the absorption of lead; and then, 20 g of each sample were tested to determine the amount of lead absorption. The results of this study, on the amount of lead absorption by the sycamore tree species at three high-traffic and one control station, showed that Takhti station had the highest amount of lead absorption (37.19 ppm) compared with other three stations. Therefore, the sycamore tree species can be an appropriate one for the margins of urban streets.

  2. Traffic engineering for Internet applications

    Science.gov (United States)

    Jena, Ajit K.; Popescu, Adrian

    2001-07-01

    The focus of the paper is on resource engineering for supporting Service Level Agreements (SLAs) in IP networks. SLA at both link level and application level are considered. Using an object-oriented simulation model a case study is presented for client-server interactions generated by mixed traffic conditions in a Frame Relay (FR) WAN. Performance issues of Short Range Dependence and Long Range Dependence traffic under different resource control regimes are compared. The results show that major portion of the end-to- end delay comes from the queueing delay at the WAN ingress points, which is due to the significant bandwidth differences that may exist between LAN and WAN link layers. The results also highlight the role TCP window size and FR PVC control mechanisms play in the provision of delay performance for Internet services.

  3. Agent Based Individual Traffic guidance

    DEFF Research Database (Denmark)

    Wanscher, Jørgen Bundgaard

    2004-01-01

    When working with traffic planning or guidance it is common practice to view the vehicles as a combined mass. >From this models are employed to specify the vehicle supply and demand for each region. As the models are complex and the calculations are equally demanding the regions and the detail...... can be obtained through cellular phone tracking or GPS systems. This information can then be used to provide individual traffic guidance as opposed to the mass information systems of today -- dynamic roadsigns and trafficradio. The goal is to achieve better usage of road and time. The main topic...... of the paper is the possibilities of using ABIT when disruptions occur (accidents, congestion, and roadwork). The discussion will be based on realistic case studies....

  4. Crowding effects in vehicular traffic.

    Science.gov (United States)

    Combinido, Jay Samuel L; Lim, May T

    2012-01-01

    While the impact of crowding on the diffusive transport of molecules within a cell is widely studied in biology, it has thus far been neglected in traffic systems where bulk behavior is the main concern. Here, we study the effects of crowding due to car density and driving fluctuations on the transport of vehicles. Using a microscopic model for traffic, we found that crowding can push car movement from a superballistic down to a subdiffusive state. The transition is also associated with a change in the shape of the probability distribution of positions from a negatively-skewed normal to an exponential distribution. Moreover, crowding broadens the distribution of cars' trap times and cluster sizes. At steady state, the subdiffusive state persists only when there is a large variability in car speeds. We further relate our work to prior findings from random walk models of transport in cellular systems.

  5. Crowding effects in vehicular traffic

    CERN Document Server

    Combinido, Jay Samuel L

    2012-01-01

    While the impact of crowding on the diffusive transport of molecules within a cell is widely studied in biology, it has thus far been neglected in traffic systems where bulk behavior is the main concern. Here, we study the effects of crowding due to car density and driving fluctuations on the transport of vehicles. Using a microscopic model for traffic, we found that crowding can push car movement from a superballistic down to a subdiffusive state. The transition is also associated with a change in the shape of the probability distribution of positions from negatively-skewed normal to an exponential distribution. Moreover, crowding broadens the distribution of cars' trap times and cluster sizes. At steady state, the subdiffusive state persists only when there is a large variability in car speeds. We further relate our work to prior findings from random walk models of transport in cellular systems.

  6. Container Traffic In European Ports

    Directory of Open Access Journals (Sweden)

    Elen Twrdy

    2004-03-01

    Full Text Available Over the last fifteen years the European transport markethas witnessed a growth of container traffic which today reachesapproximately 50 million TEU per year. From 1997 to 2002,container traffic in the northern European ports increased from14 to 20.6 million TEU per year, in the ports of the westernMedite"anean from 6 to 10 million TEU per year, and in thenorthern Adriatic ports from 0. 69 to 0. 74 million TEU per year.The ports of the northern Adriatic are located in three states(Slovenia, Croatia and Italy with different statuses in relationto the common European market. In addition, different developmentlevels of these states are reflected in different levels ofinternational commercial exchange, the development of the existinginfrastructure and plans for the construction of new infrastructures.However, all three countries share a common goaltoincrease their competitiveness in comparison with the westemEuropean ports.

  7. Car Delay Model near Bus Stops with Mixed Traffic Flow

    Directory of Open Access Journals (Sweden)

    Yang Xiaobao

    2013-01-01

    Full Text Available This paper proposes a model for estimating car delays at bus stops under mixed traffic using probability theory and queuing theory. The roadway is divided to serve motorized and nonmotorized traffic streams. Bus stops are located on the nonmotorized lanes. When buses dwell at the stop, they block the bicycles. Thus, two conflict points between car stream and other traffic stream are identified. The first conflict point occurs as bicycles merge to the motorized lane to avoid waiting behind the stopping buses. The second occurs as buses merge back to the motorized lane. The average car delay is estimated as the sum of the average delay at these two conflict points and the delay resulting from following the slower bicycles that merged into the motorized lane. Data are collected to calibrate and validate the developed model from one site in Beijing. The sensitivity of car delay to various operation conditions is examined. The results show that both bus stream and bicycle stream have significant effects on car delay. At bus volumes above 200 vehicles per hour, the curbside stop design is not appropriate because of the long car delays. It can be replaced by the bus bay design.

  8. Continuity, Stability, and Change in Daily Emotional Experience across Adolescence.

    Science.gov (United States)

    Larson, Reed W.; Moneta, Giovanni; Richards, Maryse H.; Wilson, Suzanne

    2002-01-01

    This longitudinal study examined change in 220 adolescents' daily range of emotional states between early and late adolescence. Findings showed that emotional states became less positive across early adolescence; this downward change in average emotions ceased in grade 10. The greatest relative instability was during early adolescence; stability…

  9. Traffic control: nursing practice calendar.

    Science.gov (United States)

    Rus, Linda; Cheesebro, Kathy; Nagra, Erica; Neff, Alaina

    2013-01-01

    Educating nurses on the multitude of new and updated best practices, changes in regulatory standards, new equipment, and enhanced technology creates an "information traffic jam." Multiple practice changes occurring simultaneously pose challenges for nurses to retain information to practice safely and effectively. An absence of coordination between various nursing and allied health teaching initiatives compounds this problem. A nursing practice calendar was developed to facilitate the prioritization, communication, and education of hospital-wide initiatives affecting nursing practice.

  10. Personal Property Traffic Management Regulation

    Science.gov (United States)

    1991-10-01

    transportation in domestic, domestic ( offshore ), and international traffic and determine the DOD interest and action required within the scope of the DOD...S. 0MRS 4D. LMLISERMU3S TEMPORARY j~i~ o~ ~l h PAYING P WO/F AONAWV AND MAROC O CRPS 13 . em e L a.C*KT Cn1%f ~m STAYSOF L*OAL RIQENCS 7. EmnTIEMENTS

  11. Transition characteristic analysis of traffic evolution process for urban traffic network.

    Science.gov (United States)

    Wang, Longfei; Chen, Hong; Li, Yang

    2014-01-01

    The characterization of the dynamics of traffic states remains fundamental to seeking for the solutions of diverse traffic problems. To gain more insights into traffic dynamics in the temporal domain, this paper explored temporal characteristics and distinct regularity in the traffic evolution process of urban traffic network. We defined traffic state pattern through clustering multidimensional traffic time series using self-organizing maps and construct a pattern transition network model that is appropriate for representing and analyzing the evolution progress. The methodology is illustrated by an application to data flow rate of multiple road sections from Network of Shenzhen's Nanshan District, China. Analysis and numerical results demonstrated that the methodology permits extracting many useful traffic transition characteristics including stability, preference, activity, and attractiveness. In addition, more information about the relationships between these characteristics was extracted, which should be helpful in understanding the complex behavior of the temporal evolution features of traffic patterns.

  12. A simple method to downscale daily wind statistics to hourly wind data

    CERN Document Server

    Guo, Zhongling

    2013-01-01

    Wind is the principal driver in the wind erosion models. The hourly wind speed data were generally required for precisely wind erosion modeling. In this study, a simple method to generate hourly wind speed data from daily wind statistics (daily average and maximum wind speeds together or daily average wind speed only) was established. A typical windy location with 3285 days (9 years) measured hourly wind speed data were used to validate the downscaling method. The results showed that the overall agreement between observed and simulated cumulative wind speed probability distributions appears excellent, especially for the wind speeds greater than 5 m s-1 range (erosive wind speed). The results further revealed that the values of daily average erosive wind power density (AWPD) calculated from generated wind speeds fit the counterparts computed from measured wind speeds well with high models' efficiency (Nash-Sutcliffe coefficient). So that the hourly wind speed data can be predicted from daily average and maximu...

  13. Outer Space Traffic Safety Standards

    Science.gov (United States)

    Larsen, Paul B.

    2013-09-01

    Management of traffic in outer space is a major safety problem. Traffic is increasing. Most satellites are navigable but they have to co-exist with space debris which is not navigable. We need minimum safety rules for outer space traffic. We have the possible beginnings of international safety standards in the form of national space object tracking; Global Navigation Satellite Systems (GNSS) standardization through ICAO and the International Committee on GNSS (ICG); the IADC space debris guidelines; and the proposed Code of Conduct. However, safety could be improved by standards for such activities as licensing launches of satellites into outer space; standards for accident investigation and search and rescue: operational safety zones around space objects such as the International Space Station. This paper describes legal authority for minimum safety standards. It considers safety standards established by private agreements among commercial operators. Finally it examines a number of options for an international forum to establish safety standards, including self-regulation, COPUOS, ICAO, ITU, a space code of conduct, and a new space organization.

  14. enviroCar - citizen science for sustainable traffic

    Science.gov (United States)

    Stasch, Christoph; Remke, Albert; Jirka, Simon; Nuest, Daniel

    2015-04-01

    Optimizing traffic flow is a challenging task, affecting both the mobility of people and the environment. Up to now, traffic monitoring is based on small samples using GPS devices or remote sensors such as cameras. Citizens are usually not actively involved in the process of collecting or analyzing traffic data. The enviroCar project (www.envirocar.org) aims at addressing this situation by providing an open platform that can be used by everyone to collect and analyze traffic-related data and thus to achieve sustainable traffic management by answering questions such as: How is the average speed on a certain route? Where are exceptionally long waiting times in front of traffic lights? At which crossings do more cars stop than drive through? Where are hotspots of fuel consumption and air pollutant emission during a certain time interval? In this presentation, an overview on the enviroCar project is given and current research challenges addressed in the context of the project are presented. Citizens are able to participate by registering at the enviroCar portal and downloading the enviroCar Android app. Once installed, the Android app allows citizens to collect car sensor data, e.g. speed, mass air flow, or intake temperature via an On-Board Diagnosis 2 (OBD-II) Adapter. After finishing a car ride, the data can be uploaded to the central enviroCar server where the data is anonymized and published as open data. Each enviroCar member has a profile page giving control on his own data and providing statistics on personal driving behavior. The portal also allows comparing personal statistics with the statistics of other members. It thus facilitates analysis whether, for example, a member is driving in a more fuel saving manner than other users. Besides only acting as a data collector, citizens can also explore the enviroCar data in online maps or download the data in standard formats for certain spatial areas and/or time intervals allowing them to conduct spatio

  15. Traffic instabilities in self-organized pedestrian crowds.

    Directory of Open Access Journals (Sweden)

    Mehdi Moussaïd

    Full Text Available In human crowds as well as in many animal societies, local interactions among individuals often give rise to self-organized collective organizations that offer functional benefits to the group. For instance, flows of pedestrians moving in opposite directions spontaneously segregate into lanes of uniform walking directions. This phenomenon is often referred to as a smart collective pattern, as it increases the traffic efficiency with no need of external control. However, the functional benefits of this emergent organization have never been experimentally measured, and the underlying behavioral mechanisms are poorly understood. In this work, we have studied this phenomenon under controlled laboratory conditions. We found that the traffic segregation exhibits structural instabilities characterized by the alternation of organized and disorganized states, where the lifetime of well-organized clusters of pedestrians follow a stretched exponential relaxation process. Further analysis show that the inter-pedestrian variability of comfortable walking speeds is a key variable at the origin of the observed traffic perturbations. We show that the collective benefit of the emerging pattern is maximized when all pedestrians walk at the average speed of the group. In practice, however, local interactions between slow- and fast-walking pedestrians trigger global breakdowns of organization, which reduce the collective and the individual payoff provided by the traffic segregation. This work is a step ahead toward the understanding of traffic self-organization in crowds, which turns out to be modulated by complex behavioral mechanisms that do not always maximize the group's benefits. The quantitative understanding of crowd behaviors opens the way for designing bottom-up management strategies bound to promote the emergence of efficient collective behaviors in crowds.

  16. Road Artery Traffic Light Optimization with Use of the Reinforcement Learning

    Directory of Open Access Journals (Sweden)

    Rok Marsetič

    2014-04-01

    Full Text Available The basic principle of optimal traffic control is the appropriate real-time response to dynamic traffic flow changes. Signal plan efficiency depends on a large number of input parameters. An actuated signal system can adjust very well to traffic conditions, but cannot fully adjust to stochastic traffic volume oscillation. Due to the complexity of the problem analytical methods are not applicable for use in real time, therefore the purpose of this paper is to introduce heuristic method suitable for traffic light optimization in real time. With the evolution of artificial intelligence new possibilities for solving complex problems have been introduced. The goal of this paper is to demonstrate that the use of the Q learning algorithm for traffic lights optimization is suitable. The Q learning algorithm was verified on a road artery with three intersections. For estimation of the effectiveness and efficiency of the proposed algorithm comparison with an actuated signal plan was carried out. The results (average delay per vehicle and the number of vehicles that left road network show that Q learning algorithm outperforms the actuated signal controllers. The proposed algorithm converges to the minimal delay per vehicle regardless of the stochastic nature of traffic. In this research the impact of the model parameters (learning rate, exploration rate, influence of communication between agents and reward type on algorithm effectiveness were analysed as well.

  17. Empirical Features of Spontaneous and Induced Traffic Breakdowns in Free Flow at Highway Bottlenecks

    CERN Document Server

    Kerner, Boris S; Klenov, Sergey L; Rehborn, Hubert; Leibel, Michael

    2015-01-01

    Based on an empirical study of real field traffic data measured in 1996--2014 through road detectors installed on German freeways, we reveal physical features of empirical nuclei for spontaneous traffic breakdown in free flow at highway bottlenecks. It is shown that the source of a nucleus for traffic breakdown is the solely difference between empirical spontaneous and induced traffic breakdowns at a highway bottleneck. Microscopic traffic simulations with a stochastic traffic flow model in the framework of three-phase theory explain the empirical findings. It turns out that in the most cases, a nucleus for empirical spontaneous traffic breakdown occurs through an interaction of one of waves in free flow with an empirical permanent speed disturbance localized at a highway bottleneck. The wave is a localized structure in free flow, in which the total flow rate is larger and the speed averaged across the highway is smaller than outside the wave. The waves in free flow appear due to oscilations in the percentage...

  18. Workers daily stress in the wheel

    Directory of Open Access Journals (Sweden)

    Mónica González Ramírez

    2013-07-01

    Full Text Available The aim of this study was to determine the level of stress and related factors in professional drivers of Chilpancingo, Guerrero. A cross-sectional study was conducted in a population of 191 drivers aged 19 to 74 years old. It was carried out a purposive sampling from September 2009 to January 2010. The stress measurement was obtained by applying a estresometer containing questions related to lifestyle, environmental factors, stress symptoms, employment or occupation, relationships and personality. The diagnosis of stress and recommendations according to the diagnosis obtained were given to each participant. The average age of the 191 drivers was 35.51 ± 4.11 years. In terms of marital status: 10.99% were single, 68.06% married, 5.24%divorced, 15.18% cohabiting and 0.52% widowed. Hyperstress, defined as having dangerous or high stress levels, had a prevalence of 26.7%. Factors associated with hyperstress were eating in a hurry, having the house dirty and messy, polluted air in the area where they live, suffering tachycardia, feeling tightness for work, feeling the long day at work, being affected by disputes, being nervous if interrupted while working, getting nervous when traffic is heavy, suffering insomnia, sweating a lot without exercise and not getting along with the boss.

  19. Influence of tourism and traffic on the Eurasian lynx hunting activity and daily movements

    Directory of Open Access Journals (Sweden)

    Belotti, E.

    2012-01-01

    Full Text Available Human presence influences survival of large carnivores in several ways and even outdoor activities can be a source of disturbance. As ungulate prey provide the Eurasian lynx (Lynx lynx with food for several nights and the pattern of lynx activity is mainly shaped by searching for and consuming large prey, the need to move decreases strongly while the prey is eaten. However, during the day, human activity may drive lynx to move to safe shelters and habitat features such as dense vegetation may increase tolerance. In the Bohemian Forest (Czech Republic, we found 116 prey killed by five GPS–collared lynxes. We tested whether the kill sites were located farther from roads or tourist trails than a set of randomly generated locations and whether presence of roads or tourist trails and habitat structure influenced the distance ‘kill site to daytime resting sites’. At night, with low human activity, lynxes did not avoid roads and even selected the surroundings of tourist trails. The distance ‘kill site to daytime resting sites’ correlated negatively with presence of habitat concealment and distance to tourist trails, suggesting that outdoor activities may have to be considered in lynx management plans.

  20. Tractor Operation and Daily Care.

    Science.gov (United States)

    Fore, J. M.; And Others

    Written for the tractor operator, the manual describes, with the aid of colored illustrations and diagrams, the tasks involved in the proper operation and daily maintenance of tractors. It offers explanations for the desirability of the various servicing and adjustment operations, as well as guidelines for tractor operation and safety. The…

  1. On polar daily geomagnetic variation

    Directory of Open Access Journals (Sweden)

    Paola De Michelis

    2015-11-01

    Full Text Available The aim of this work is to investigate the nature of the daily magnetic field perturbations produced by ionospheric and magnetospheric currents at high latitudes. We analyse the hourly means of the X and Y geomagnetic field components recorded by a meridian chain of permanent geomagnetic observatories in the polar region of the Northern Hemisphere during a period of four years (1995-1998 around the solar minimum. We apply a mathematical method, known as natural orthogonal component (NOC, which is capable of characterizing the dominant modes of the geomagnetic field daily variability through a set of empirical orthogonal functions (EOFs. Using the first two modes we reconstruct a two-dimensional equivalent current representation of the ionospheric electric currents, which contribute substantially to the geomagnetic daily variations. The obtained current structures resemble the equivalent current patterns of DP2 and DP1. We characterize these currents by studying their evolution with the geomagnetic activity level and by analysing their dependence on the interplanetary magnetic field. The obtained results support the idea of a coexistence of two main processes during all analysed period although one of them, the directly driven process, represents the dominant component of the geomagnetic daily variation.

  2. Daily practices, consumption and citizenship.

    Science.gov (United States)

    Mazzarino, Jane M; Morigi, Valdir J; Kaufmann, Cristine; Farias, Alessandra M B; Fernandes, Diefersom A

    2011-12-01

    This paper promotes a reflection on the relationship between daily practices and consumption. Understanding how conflicts, resistance and consensus are generated from daily consumption practices opens up possibilities for reflecting on the construction of sustainability in the context of diversity, one of the landmarks of the globalized world. Within this socio-cultural context, the central issue is: can consumption generate citizenship practices? The concepts of subject and agent help one think about collective action and subjectivation processes and their interferences on the collective consuming behavior. Based on empirical data from a research carried out in the municipality of Estrela in 2007, in the Taquari Valley - Rio Grande do Sul (Southern Brazil) on local reality consumption practices, it was possible to conclude that various reasoning mechanisms and values underlie the daily consumption practices. Citizenship construction, based on consumption practices, depends on the subject's reflection capacity on his/her daily practices or on what goes through the circulation of environmental information based on sociability spaces.

  3. Brazilian road traffic fatalities: a spatial and environmental analysis.

    Directory of Open Access Journals (Sweden)

    Luciano de Andrade

    Full Text Available BACKGROUND: Road traffic injuries (RTI are a major public health epidemic killing thousands of people daily. Low and middle-income countries, such as Brazil, have the highest annual rates of road traffic fatalities. In order to improve road safety, this study mapped road traffic fatalities on a Brazilian highway to determine the main environmental factors affecting road traffic fatalities. METHODS AND FINDINGS: Four techniques were utilized to identify and analyze RTI hotspots. We used spatial analysis by points by applying kernel density estimator, and wavelet analysis to identify the main hot regions. Additionally, built environment analysis, and principal component analysis were conducted to verify patterns contributing to crash occurrence in the hotspots. Between 2007 and 2009, 379 crashes were notified, with 466 fatalities on BR277. Higher incidence of crashes occurred on sections of highway with double lanes (ratio 2∶1. The hotspot analysis demonstrated that both the eastern and western regions had higher incidences of crashes when compared to the central region. Through the built environment analysis, we have identified five different patterns, demonstrating that specific environmental characteristics are associated with different types of fatal crashes. Patterns 2 and 4 are constituted mainly by predominantly urban characteristics and have frequent fatal pedestrian crashes. Patterns 1, 3 and 5 display mainly rural characteristics and have higher prevalence of vehicular collisions. In the built environment analysis, the variables length of road in urban area, limited lighting, double lanes roadways, and less auxiliary lanes were associated with a higher incidence of fatal crashes. CONCLUSIONS: By combining different techniques of analyses, we have identified numerous hotspots and environmental characteristics, which governmental or regulatory agencies could make use to plan strategies to reduce RTI and support life-saving policies.

  4. Crash Prediction and Risk Evaluation Based on Traffic Analysis Zones

    Directory of Open Access Journals (Sweden)

    Cuiping Zhang

    2014-01-01

    Full Text Available Traffic safety evaluation for traffic analysis zones (TAZs plays an important role in transportation safety planning and long-range transportation plan development. This paper aims to present a comprehensive analysis of zonal safety evaluation. First, several criteria are proposed to measure the crash risk at zonal level. Then these criteria are integrated into one measure-average hazard index (AHI, which is used to identify unsafe zones. In addition, the study develops a negative binomial regression model to statistically estimate significant factors for the unsafe zones. The model results indicate that the zonal crash frequency can be associated with several social-economic, demographic, and transportation system factors. The impact of these significant factors on zonal crash is also discussed. The finding of this study suggests that safety evaluation and estimation might benefit engineers and decision makers in identifying high crash locations for potential safety improvements.

  5. Relevant Affect Factors of Smartphone Mobile Data Traffic

    Directory of Open Access Journals (Sweden)

    Siniša Husnjak

    2016-08-01

    Full Text Available Smartphones are used to access a wide range of different information and communication services and perform functions based on data transfer. A number of subscription contracts for smartphones is rapidly increasing, and the development of mobile communications network provides higher speed of data transfer. The continuous increase in the average amount of data traffic per one subscriber contract leads to an increase in the total Mobile Data Traffic (MDT, globally. This research represents a summary of factors that affect the amount of smartphone MDT. Previous literature shows only a few of the factors individually that affect the realization of smartphone MDT. The results of the research clarify the ways which influence the amount of MDT generated by a smartphone. This paper increases the awareness of the users of the methods of generating smartphone MDT. The research also allows users to specify parameters that affect the prediction of generated MDT of a smartphone.

  6. Effect of desired speed variability on highway traffic flow.

    Science.gov (United States)

    Lipshtat, Azi

    2009-06-01

    Traffic flow is a function of many natural, environmental, and human factors. Not only that weather and road condition can vary, but drivers' decisions and policies also can affect the flow. Here we analyze the effect of distribution of desired speeds. We show that a broader distribution can reduce the flow efficiency and increase congestions. Since different drivers react differently to changes in weather or road conditions, such a change leads to a change in desired speed distribution as well. As a result, nonintuitive changes in traffic flow may occur. Besides providing insight and analyzing the underlying mechanism of a collective phenomenon, this example sheds light on a fundamental aspect of computational modeling. Although "mean-field" models that deal with average values only and ignore variability are simpler and easier to analyze, they can very easily turn into oversimplifications and miss relevant qualitative phenomena.

  7. Comparison of traffic assignment in VISUM and transport simulation in MATSim

    Directory of Open Access Journals (Sweden)

    Bartłomiej PIĄTKOWSKI

    2013-01-01

    Full Text Available The paper presents a comparison of different approaches to traffic modelling and forecasting in VISUM and MATSim. The comparison was based on three indicators: link volumes, average travel time and distance. For this purpose, a virtual city with a road network and an OD matrix describing travel demands were created. Next the input data were created to both systems. The equilibrium and the dynamic stochastic assignment algorithms were used in VISUM while in MATSim a multi-agent approach was used for planning and a queue-based flow model for simulation. The comparison showed that although the overall results obtained in both systems were convergent, the detailed distribution of traffic was different. In VISUM the static assignment algorithm resulted in increased traffic flow on links located near to the connectors, while the dynamic one assigned traffic more uniformly, matching the MATSim’s results.

  8. Statistical characterization of deviations from planned flight trajectories in air traffic management

    CERN Document Server

    Bongiorno, C; Lillo, F; Mantegna, R N; Miccichè, S

    2016-01-01

    Understanding the relation between planned and realized flight trajectories and the determinants of flight deviations is of great importance in air traffic management. In this paper we perform an in depth investigation of the statistical properties of planned and realized air traffic on the German airspace during a 28 day periods, corresponding to an AIRAC cycle. We find that realized trajectories are on average shorter than planned ones and this effect is stronger during night-time than daytime. Flights are more frequently deviated close to the departure airport and at a relatively large angle to destination. Moreover, the probability of a deviation is higher in low traffic phases. All these evidences indicate that deviations are mostly used by controllers to give directs to flights when traffic conditions allow it. Finally we introduce a new metric, termed difork, which is able to characterize navigation points according to the likelihood that a deviation occurs there. Difork allows to identify in a statist...

  9. Analysis and Modeling of Traffic in Modern Data Communication Networks

    OpenAIRE

    Babic, G.; Vandalore, B.; Jain, R.

    1998-01-01

    In performance analysis and design of communication netword modeling data traffic is important. With introduction of new applications, the characteristics of the data traffic changes. We present a brief review the different models of data traffic and how they have evolved. We present results of data traffic analysis and simulated traffic, which demonstrates that the packet train model fits the traffic at source destination level and long-memory (self-similar) model fits the traffic at the agg...

  10. Epidemiological analysis of traffic accident trauma in Gansu province in 1996

    Institute of Scientific and Technical Information of China (English)

    张向东; 代荫梅

    1999-01-01

    Objective To analyze the epidemiologic data of traffic trauma in Gansu province in 1996 and try to find effective ways to reduce the injury.Methods The data were gathered from the General Team o the Traffic Police of Gansu Province and analyzed together with other related data.Results Although the traffic accidents in Gansu province were reduced in last two years as a result of traffic safety education,the number of casuatlties has not been evidently reduced.The number of deaths caused by traffic accidents was 983 in 1996.The main causes of these deaths were the negligence of the drivers,carelessness of the pedestrians and the bike riders,the sudden breakdown of the machine parts of the vehicles,and non-licensed driving.Among the number of deaths 69 percent was caused by violation of traffic regulations by drivers.Most of the death accidents happened at straight roads and road-crosses.The percentage was 64% and 11%,respectively.The most of deaths,about 81%,took place in sunny days.The main reason was due to the careless and exceeding-speed-limit driving.The young and middle aged were about 77% of the dead,most likely because they are the dominant group in daily work and life.Conclusions To strengthen the propaganda of traffic regulations,improve driver's moral qualities and raise the management level are very important for reducing traffic accidents.Correct and timely first aid before being hospitalized can also greatly reduce the mortality.

  11. Effect of Adaptive Delivery Capacity on Networked Traffic Dynamics

    Institute of Scientific and Technical Information of China (English)

    CAO Xian-Bin; DU Wen-Bo; CHEN Cai-Long; ZHANG Jun

    2011-01-01

    @@ We introduce an adaptive delivering capacity mechanism into the traffic dynamic model on scale-free networks under shortest path routing strategy and focus on its effect on the network capacity measured by the critical point(Rc) of phase transition from free flow to congestion.Under this mechanism,the total node's delivering capacity is fixed and the allocation of delivering capacity on node i is proportional to niφ,where ni is the queue length of node i and φ is the adjustable parameter.It is found that the network capacity monotonously increases with the increment of φ,but there exists an optimal value of parameter φ leading to the highest transportation efficiency measured by average travelling time(〈T〉).Our work may be helpful for optimal design of networked traffic dynamics.%We introduce an adaptive delivering capacity mechanism into the traffic dynamic model on scale-free networks under shortest path routing strategy and focus on its effect on the network capacity measured by the critical point (Rc) of phase transition from free flow to congestion.Under this mechanism, the total node's delivering capacity is fixed and the allocation of delivering capacity on node i is proportional to niφ, where ni is the queue length of node i and φ is the adjustable parameter.It is found that the network capacity monotonously increases with the increment of φ, but there exists an optimal value of parameter φ leading to the highest transportation efficiency measured by average travelling time (<T>).Our work may be helpful for optimal design of networked traffic dynamics.

  12. Causes of daily cycle variability of atmospheric pollutants in a western Mediterranean urban site (DAURE campaign)

    Science.gov (United States)

    Reche, Cristina; Moreno, Teresa; Viana, Mar; Querol, Xavier; Alastuey, Andrés.; Jimenez, Jose L.; Pandolfi, Marco; Amato, Fulvio; Pérez, Noemí; Moreno, Natalia

    2010-05-01

    The 2009 DAURE Aerosol Campaign (23-February-2009 to 27-March-2009 and 1-July to 31-July) (see Presentation: Pandolfi et al., section AS3.2) had the objective of characterising the main sources and chemical processes controlling atmospheric pollution due to particulate matter in the Mediterranean site of Barcelona (Spain). An urban and a rural background site were selected in order to describe both kinds of pollution setting. Several parameters were taken into consideration, including the variability of mass concentration in the coarse and fine fractions, particle number, amount of black carbon and the concentration of gaseous pollutants (SO2, H2S, NO, NO2, CO, O3) present. Comparisons between the chemical composition of ambient atmospheric particles during day versus night were made using twelve-hour PM samples. The data shown here are focused on results obtained for the urban site where two main atmospheric settings were distinguishable in winter, namely Atlantic advection versus local air mass recirculation. During the warmer months Saharan dust intrusions added a third important influence on PM background. The data demonstrate that superimposed upon these background influences on city air quality are important local contributions from road traffic, construction-demolition works and shipping. There is also a major local contribution of secondary aerosols, with elevated number of particles occurring at midday (and especially in summer) when nucleation processes are favoured by photochemistry. Concentrations of SO2 peak at different times to the other gaseous pollutants due to regular daytime onshore south-easterly breezes bringing harbour emissions into the city. Road traffic in Barcelona also has a great impact on air quality, as demonstrated by daily and weekly cycles of gaseous pollutants, black carbon and the finer fraction of PM, with peaks being coincident with traffic rush-hours (8-10h and 20-22h), levels of pollution increasing from Monday to Friday, and

  13. HYBRID INTERNET TRAFFIC CLASSIFICATION TECHNIQUE1

    Institute of Scientific and Technical Information of China (English)

    Li Jun; Zhang Shunyi; Lu Yanqing; Yan Junrong

    2009-01-01

    Accurate and real-time classification of network traffic is significant to network operation and management such as QoS differentiation, traffic shaping and security surveillance. However, with many newly emerged P2P applications using dynamic port numbers, masquerading techniques, and payload encryption to avoid detection, traditional classification approaches turn to be ineffective. In this paper, we present a layered hybrid system to classify current Internet traffic, motivated by variety of network activities and their requirements of traffic classification. The proposed method could achieve fast and accurate traffic classification with low overheads and robustness to accommodate both known and unknown/encrypted applications. Furthermore, it is feasible to be used in the context of real-time traffic classification. Our experimental results show the distinct advantages of the proposed classification system, compared with the one-step Machine Learning (ML) approach.

  14. Traffic Flow Management Wrap-Up

    Science.gov (United States)

    Grabbe, Shon

    2011-01-01

    Traffic Flow Management involves the scheduling and routing of air traffic subject to airport and airspace capacity constraints, and the efficient use of available airspace. Significant challenges in this area include: (1) weather integration and forecasting, (2) accounting for user preferences in the Traffic Flow Management decision making process, and (3) understanding and mitigating the environmental impacts of air traffic on the environment. To address these challenges, researchers in the Traffic Flow Management area are developing modeling, simulation and optimization techniques to route and schedule air traffic flights and flows while accommodating user preferences, accounting for system uncertainties and considering the environmental impacts of aviation. This presentation will highlight some of the major challenges facing researchers in this domain, while also showcasing recent innovations designed to address these challenges.

  15. Suppressing Redundancy in Wireless Sensor Network Traffic

    Science.gov (United States)

    Abe, Rey; Honiden, Shinichi

    Redundancy suppression is a network traffic compression technique that, by caching recurring transmission contents at receiving nodes, avoids repeatedly sending duplicate data. Existing implementations require abundant memory both to analyze recent traffic for redundancy and to maintain the cache. Wireless sensor nodes at the same time cannot provide such resources due to hardware constraints. The diversity of protocols and traffic patterns in sensor networks furthermore makes the frequencies and proportions of redundancy in traffic unpredictable. The common practice of narrowing down search parameters based on characteristics of representative packet traces when dissecting data for redundancy thus becomes inappropriate. Such difficulties made us devise a novel protocol that conducts a probabilistic traffic analysis to identify and cache only the subset of redundant transfers that yields most traffic savings. We verified this approach to perform close enough to a solution built on exhaustive analysis and unconstrained caching to be practicable.

  16. Traffic and Granular Flow ’07

    CERN Document Server

    Chevoir, François; Gondret, Philippe; Lassarre, Sylvain; Lebacque, Jean-Patrick; Schreckenberg, Michael

    2009-01-01

    This book covers several research fields, all of which deal with transport. Three main topics are treated: road traffic, granular matter, and biological transport. Different points of view, i.e. modelling, simulations, experiments, and phenomenological observations, are considered. Sub-topics include: highway or urban vehicular traffic (dynamics of traffic, macro/micro modelling, measurements, data analysis, security issues, psychological issues), pedestrian traffic, animal traffic (e.g. social insects), collective motion in biological systems (molecular motors...), granular flow (dense flows, intermittent flows, solid/liquid transition, jamming, force networks, fluid and solid friction), networks (biological networks, urban traffic, the internet, vulnerability of networks, optimal transport networks) and cellular automata applied to the various aforementioned fields.

  17. Car-following models of vehicular traffic

    Institute of Scientific and Technical Information of China (English)

    翁彦琳; 吴铁军

    2002-01-01

    The Car-following model is a kind of microscopic simulation model for vehicular traffic, which describe the one-by-one following behaviors of vehides in the same traffic lane. As a common traffic phenomenon, following behavior is of great importance in the micro-study of intelligent traffic control.Compared with other traffic-flow models, car-following model embodies the human factors and feflects the real traffic sit-uation in a better way. This paper gives a systematic review of the development and actuality of car-following models by introducing and analyzing in detail the advantages and disavantages of GHR model, OV model,CA model and fuzzy-logic model. In addition, local stability and asymptotic stability of car-following models are discussed in this paper.

  18. 11th Traffic and Granular Flow Conference

    CERN Document Server

    Daamen, Winnie

    2016-01-01

    The Conference on Traffic and Granular Flow brings together international researchers from different fields ranging from physics to computer science and engineering to discuss the latest developments in traffic-related systems. Originally conceived to facilitate new ideas by considering the similarities of traffic and granular flow, TGF'15, organised by Delft University of Technology, now covers a broad range of topics related to driven particle and transport systems. Besides the classical topics of granular flow and highway traffic, its scope includes data transport (Internet traffic), pedestrian and evacuation dynamics, intercellular transport, swarm behaviour and the collective dynamics of other biological systems. Recent advances in modelling, computer simulation and phenomenology are presented, and prospects for applications, for example to traffic control, are discussed. The conference explores the interrelations between the above-mentioned fields and offers the opportunity to stimulate interdisciplinar...

  19. Car-following models of vehicular traffic

    Institute of Scientific and Technical Information of China (English)

    翁彦琳; 吴铁军

    2002-01-01

    The Car-following models is a kind of microscopic simulation model f or vehicular traffic, which describe the one-by-one following behaviors of v ehicles in the same traffic lane. As a common traffic phenomenon, following behavior is of great importance in the micro-study of intelligent traffic control. Compared with other traffic-flow models, car-following model embodies the human factors a nd reflects the real traffic situation in a better way. This paper gives a syste matic review of the development and actuality of car-following models by introd u cing and analyzing in detail the advantages and disadvantages of GHR model, OV m odel, CA model and fuzzy-logic model. In addition, local stability and asymptot ic stability of car-following models are discussed in this paper.

  20. Using Visualization Techniques in Multilayer Traffic Modeling

    Science.gov (United States)

    Bragg, Arnold

    We describe visualization techniques for multilayer traffic modeling - i.e., traffic models that span several protocol layers, and traffic models of protocols that cross layers. Multilayer traffic modeling is challenging, as one must deal with disparate traffic sources; control loops; the effects of network elements such as IP routers; cross-layer protocols; asymmetries in bandwidth, session lengths, and application behaviors; and an enormous number of complex interactions among the various factors. We illustrate by using visualization techniques to identify relationships, transformations, and scaling; to smooth simulation and measurement data; to examine boundary cases, subtle effects and interactions, and outliers; to fit models; and to compare models with others that have fewer parameters. Our experience suggests that visualization techniques can provide practitioners with extraordinary insight about complex multilayer traffic effects and interactions that are common in emerging next-generation networks.

  1. A System for Traffic Violation Detection

    Directory of Open Access Journals (Sweden)

    Nourdine Aliane

    2014-11-01

    Full Text Available This paper describes the framework and components of an experimental platform for an advanced driver assistance system (ADAS aimed at providing drivers with a feedback about traffic violations they have committed during their driving. The system is able to detect some specific traffic violations, record data associated to these faults in a local data-base, and also allow visualization of the spatial and temporal information of these traffic violations in a geographical map using the standard Google Earth tool. The test-bed is mainly composed of two parts: a computer vision subsystem for traffic sign detection and recognition which operates during both day and nighttime, and an event data recorder (EDR for recording data related to some specific traffic violations. The paper covers firstly the description of the hardware architecture and then presents the policies used for handling traffic violations.

  2. A System for Traffic Violation Detection

    Science.gov (United States)

    Aliane, Nourdine; Fernandez, Javier; Mata, Mario; Bemposta, Sergio

    2014-01-01

    This paper describes the framework and components of an experimental platform for an advanced driver assistance system (ADAS) aimed at providing drivers with a feedback about traffic violations they have committed during their driving. The system is able to detect some specific traffic violations, record data associated to these faults in a local data-base, and also allow visualization of the spatial and temporal information of these traffic violations in a geographical map using the standard Google Earth tool. The test-bed is mainly composed of two parts: a computer vision subsystem for traffic sign detection and recognition which operates during both day and nighttime, and an event data recorder (EDR) for recording data related to some specific traffic violations. The paper covers firstly the description of the hardware architecture and then presents the policies used for handling traffic violations. PMID:25421737

  3. Green Wave Traffic Optimization - A Survey

    DEFF Research Database (Denmark)

    Warberg, Andreas; Larsen, Jesper; Jørgensen, Rene Munk

    The objective of this survey is to cover the research in the area of adaptive traffic control with emphasis on the applied optimization methods. The problem of optimizing traffic signals can be viewed in various ways, depending on political, economic and ecological goals. The survey highlights some......-based, approach, which is shown to be more suitable for adaptive traffic control. To support this claim three adaptive systems, which use alternatives to the classical optimization procedures, are described in detail....

  4. Traffic forecasts under uncertainty and capacity constraints

    OpenAIRE

    2009-01-01

    Traffic forecasts provide essential input for the appraisal of transport investment projects. However, according to recent empirical evidence, long-term predictions are subject to high levels of uncertainty. This paper quantifies uncertainty in traffic forecasts for the tolled motorway network in Spain. Uncertainty is quantified in the form of a confidence interval for the traffic forecast that includes both model uncertainty and input uncertainty. We apply a stochastic simulation process bas...

  5. Empirical synchronized flow in oversaturated city traffic

    Science.gov (United States)

    Kerner, Boris S.; Hemmerle, Peter; Koller, Micha; Hermanns, Gerhard; Klenov, Sergey L.; Rehborn, Hubert; Schreckenberg, Michael

    2014-09-01

    Based on a study of anonymized GPS probe vehicle traces measured by personal navigation devices in vehicles randomly distributed in city traffic, empirical synchronized flow in oversaturated city traffic has been revealed. It turns out that real oversaturated city traffic resulting from speed breakdown in a city in most cases can be considered random spatiotemporal alternations between sequences of moving queues and synchronized flow patterns in which the moving queues do not occur.

  6. A Bathtub Model of Traffic Congestion

    OpenAIRE

    Arnott, Richard

    2011-01-01

    In the standard economic models of traffic congestion, traffic flow does not fall under heavily congested conditions. But this is counter to experience, especially in thedowntown areas of most major cities during rush hour. This paper presents a bathtub model of traffic congestion. The height of water in the bathtub corresponds totraffic density, velocity is negatively related to density, and outflow is the product of density and velocity. Above a critical density, outflow falls as density in...

  7. Real-Time Corrected Traffic Correlation Model for Traffic Flow Forecasting

    Directory of Open Access Journals (Sweden)

    Hua-pu Lu

    2015-01-01

    Full Text Available This paper focuses on the problems of short-term traffic flow forecasting. The main goal is to put forward traffic correlation model and real-time correction algorithm for traffic flow forecasting. Traffic correlation model is established based on the temporal-spatial-historical correlation characteristic of traffic big data. In order to simplify the traffic correlation model, this paper presents correction coefficients optimization algorithm. Considering multistate characteristic of traffic big data, a dynamic part is added to traffic correlation model. Real-time correction algorithm based on Fuzzy Neural Network is presented to overcome the nonlinear mapping problems. A case study based on a real-world road network in Beijing, China, is implemented to test the efficiency and applicability of the proposed modeling methods.

  8. Spatial and temporal variations in traffic-related particulate matter at New York City high schools

    Science.gov (United States)

    Patel, Molini M.; Chillrud, Steven N.; Correa, Juan C.; Feinberg, Marian; Hazi, Yair; Deepti, K. C.; Prakash, Swati; Ross, James M.; Levy, Diane; Kinney, Patrick L.

    Relatively little is known about exposures to traffic-related particulate matter at schools located in dense urban areas. The purpose of this study was to examine the influences of diesel traffic proximity and intensity on ambient concentrations of fine particulate matter (PM 2.5) and black carbon (BC), an indicator of diesel exhaust particles, at New York City (NYC) high schools. Outdoor PM 2.5 and BC were monitored continuously for 4-6 weeks at each of 3 NYC schools and 1 suburban school located 40 km upwind of the city. Traffic count data were obtained using an automated traffic counter or video camera. BC concentrations were 2-3 fold higher at urban schools compared with the suburban school, and among the 3 urban schools, BC concentrations were higher at schools located adjacent to highways. PM 2.5 concentrations were significantly higher at urban schools than at the suburban school, but concentrations did not vary significantly among urban schools. Both hourly average counts of trucks and buses and meteorological factors such as wind direction, wind speed, and humidity were significantly associated with hourly average ambient BC and PM 2.5 concentrations in multivariate regression models. An increase of 443 trucks/buses per hour was associated with a 0.62 μg/m 3 increase in hourly average BC at an NYC school located adjacent to a major interstate highway. Car traffic counts were not associated with BC. The results suggest that local diesel vehicle traffic may be important sources of airborne fine particles in dense urban areas and consequently may contribute to local variations in PM 2.5 concentrations. In urban areas with higher levels of diesel traffic, local, neighborhood-scale monitoring of pollutants such as BC, which compared to PM 2.5, is a more specific indicator of diesel exhaust particles, may more accurately represent population exposures.

  9. ATM traffic-policing and traffic-shaping measurements

    Science.gov (United States)

    Pugaczewski, Jack T.; Sanderson, Dave; Hoffman, David W.

    1997-10-01

    ATM (Asynchronous Transfer Mode) defines several Quality of Service (QoS) levels such as CBR (Constant Bit Rate) and VBR (Variable Bit Rate). Each service has parameters that are associated with its performance characteristic. The parameters used for specifying CBR service are Peak Cell Rate (PCR) and Cell Delay Variation Tolerance (CDVTOL). The parameters used for specifying VBR service are PCR, SCR (Sustainable Cell Rate), and BT (Burst Tolerance). The network takes responsibility for monitoring and policing the traffic of each VCC/VPC at the ingress of the network. The CPE needs to traffic shape at the ingress of the network in order to meet the contracted QoS requirements. Measurement procedures and tools are required in order to provide a means of tuning the CPE and network service to meet the customer's end-to-end QoS expectations. The following paper describes how the Generic Cell Rate Algorithm variables can be adjusted to provide acceptable levels of QoS in a mixed VBR, and CBR environment. In addition, the paper examines a methodology for measuring the performance of VBR and CBR services. The authors uses this information to build a QoS measurement tool.

  10. Air traffic management evaluation tool

    Science.gov (United States)

    Sridhar, Banavar (Inventor); Sheth, Kapil S. (Inventor); Chatterji, Gano Broto (Inventor); Bilimoria, Karl D. (Inventor); Grabbe, Shon (Inventor); Schipper, John F. (Inventor)

    2012-01-01

    Methods for evaluating and implementing air traffic management tools and approaches for managing and avoiding an air traffic incident before the incident occurs. A first system receives parameters for flight plan configurations (e.g., initial fuel carried, flight route, flight route segments followed, flight altitude for a given flight route segment, aircraft velocity for each flight route segment, flight route ascent rate, flight route descent route, flight departure site, flight departure time, flight arrival time, flight destination site and/or alternate flight destination site), flight plan schedule, expected weather along each flight route segment, aircraft specifics, airspace (altitude) bounds for each flight route segment, navigational aids available. The invention provides flight plan routing and direct routing or wind optimal routing, using great circle navigation and spherical Earth geometry. The invention provides for aircraft dynamics effects, such as wind effects at each altitude, altitude changes, airspeed changes and aircraft turns to provide predictions of aircraft trajectory (and, optionally, aircraft fuel use). A second system provides several aviation applications using the first system. Several classes of potential incidents are analyzed and averted, by appropriate change en route of one or more parameters in the flight plan configuration, as provided by a conflict detection and resolution module and/or traffic flow management modules. These applications include conflict detection and resolution, miles-in trail or minutes-in-trail aircraft separation, flight arrival management, flight re-routing, weather prediction and analysis and interpolation of weather variables based upon sparse measurements. The invention combines these features to provide an aircraft monitoring system and an aircraft user system that interact and negotiate changes with each other.

  11. Robust Traffic Flow Management: Coevolutionary Approach Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We will develop a Coevolutionary Decision Support Tool (CDST) that explicitly incorporates weather uncertainty (non-probabilistically) into strategic Traffic Flow...

  12. Urban Traffic Information Service Application Grid

    Institute of Scientific and Technical Information of China (English)

    Chang-Jun Jiang; Yang Luo; An-Qing Zhou; Lin Chen; Lei Liu; Zhao-Hui Zhang; Guo-Sun Zeng; Hong-Zhong Chen; Duo-Qian Miao; Yu Fang; Xiao-Feng Tao; Qing Zhi; Feng Yue

    2005-01-01

    Traffic information processing is very complicated because of dynamic, cooperative and distributed features. This paper describes the prototype system version 2.0 of Urban Traffic Information Service Application Grid (UTISAG),which is based on the previous version. In this version, a new architecture and more enhanced services are introduced.The remarkable characteristic of the new system is providing dynamic information services for travelers by grid technology. Therefore, the key research includes integrating large multi-source traffic data, forecasting route status, simulating regional traffic flow parallelly, and implementing optimum dynamic travel scheme based on massive GPS data.

  13. Synchronized flow in oversaturated city traffic

    Science.gov (United States)

    Kerner, Boris S.; Klenov, Sergey L.; Hermanns, Gerhard; Hemmerle, Peter; Rehborn, Hubert; Schreckenberg, Michael

    2013-11-01

    Based on numerical simulations with a stochastic three-phase traffic flow model, we reveal that moving queues (moving jams) in oversaturated city traffic dissolve at some distance upstream of the traffic signal while transforming into synchronized flow. It is found that, as in highway traffic [Kerner, Phys. Rev. EPLEEE81539-375510.1103/PhysRevE.85.036110 85, 036110 (2012)], such a jam-absorption effect in city traffic is explained by a strong driver's speed adaptation: Time headways (space gaps) between vehicles increase upstream of a moving queue (moving jam), resulting in moving queue dissolution. It turns out that at given traffic signal parameters, the stronger the speed adaptation effect, the shorter the mean distance between the signal location and the road location at which moving queues dissolve fully and oversaturated traffic consists of synchronized flow only. A comparison of the synchronized flow in city traffic found in this Brief Report with synchronized flow in highway traffic is made.

  14. Traffic Flow Characteristics with Transportation Plans Components

    Directory of Open Access Journals (Sweden)

    Hrvoje Baričević

    2012-10-01

    Full Text Available Knowledge of traffic characteristics is useful to the highwayengineer in developing highway and transportation plans, performingeconomic analyses, establishing geometric design criteria,selecting and implementing traffic control measures, andevaluating the pe1[ormance of transportation facilities. Doze/ISof measures have been employed to describe the quality andquantity of traffic flow. This paper presents information onthose flow characteristics that fundamentally bear on the planning,design, and operation of highway and transport facilities:traffic speed, travel time, volume, and density.

  15. Reducing Traffic Congestions by Introducing CACC-Vehicles on a Multi-Lane Highway Using Agent-Based Approach

    Science.gov (United States)

    Arnaout, Georges M.; Bowling, Shannon R.

    2011-01-01

    Traffic congestion is an ongoing problem of great interest to researchers from different areas in academia. With the emerging technology for inter-vehicle communication, vehicles have the ability to exchange information with predecessors by wireless communication. In this paper, we present an agent-based model of traffic congestion and examine the impact of having CACC (Cooperative Adaptive Cruise Control) embedded vehicle(s) on a highway system consisting of 4 traffic lanes without overtaking. In our model, CACC vehicles adapt their acceleration/deceleration according to vehicle-to-vehicle inter-communication. We analyze the average speed of the cars, the shockwaves, and the evolution of traffic congestion throughout the lifecycle of the model. The study identifies how CACC vehicles affect the dynamics of traffic flow on a complex network and reduce the oscillatory behavior (stop and go) resulting from the acceleration/deceleration of the vehicles.

  16. A latency analysis for M2M and OG-like traffic patterns in different HSPA core network configurations

    Directory of Open Access Journals (Sweden)

    M. V. Popović

    2014-11-01

    Full Text Available In this paper we present an analysis intended to reveal possible impacts of core network features on latency for modelled M2M and Online Gaming traffic. Simulations were performed in a live 3G/HSPA network. Test traffic simulating multiplayer real-time games and M2M applications was generated on 10 mobile phones in parallel, sending data to a remote server. APNs with different combinations of hardware and features (proxy server, different GGSNs and firewalls, usage of Service Awareness feature were chosen. The traffic was recorded on the Gn interface in the mobile core. The goal of experiments was to evaluate any eventually significant variation of average recorded RTTs in the core part of mobile network that would clearly indicate either the impact of used APN on delay for a specific traffic pattern, or selectivity of the APN towards different traffic patterns.

  17. Critical density of urban traffic

    CERN Document Server

    da Silva, Adilton Jose

    2010-01-01

    A modified version of the Intelligent Driver Model was used to simulate traffic in the district of Afogados, in the city of Recife, Brazil, with the objective to verify whether the complexity of the underlying street grid, with multiple lane streets, crossings, and semaphores, is capable of exhibiting the effect of critical density: appearance of a maximum in the vehicle flux versus density curve. Numerical simulations demonstrate that this effect indeed is observed on individual avenues, while the phase offset among the avenues results in damping of this effect for the region as a whole.

  18. Sociological study on the course of the traffic system and the traffic accidents

    OpenAIRE

    Yaşar Erjem

    2007-01-01

    The subject of this research is the operation of the traffic system and traffic accidents from a sociological perspective. In the research , the traffic system is taken as a sub-system of the social system. In this context the effects of the social, cultural and demographic factors on traffic accidents are examined . The data were collected from 681 people of whom 300 are drivers 300 pedestrians, 4 directors and 20 instructors of driving courses in Konya in Turkey. The research findings showe...

  19. 50 CFR 20.24 - Daily limit.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Daily limit. 20.24 Section 20.24 Wildlife... (CONTINUED) MIGRATORY BIRD HUNTING Taking § 20.24 Daily limit. No person shall take in any 1 calendar day, more than the daily bag limit or aggregate daily bag limit, whichever applies....

  20. 32 CFR 634.24 - Traffic planning and codes.

    Science.gov (United States)

    2010-07-01

    ..., and points of congestion. The installation law enforcement officer and traffic engineer usually... 32 National Defense 4 2010-07-01 2010-07-01 true Traffic planning and codes. 634.24 Section 634.24... CRIMINAL INVESTIGATIONS MOTOR VEHICLE TRAFFIC SUPERVISION Traffic Supervision § 634.24 Traffic planning...

  1. MPLS & Internet Traffic Engineering%MPLS和Internet流量工程

    Institute of Scientific and Technical Information of China (English)

    孟魁; 张根度

    2001-01-01

    Rapid growth of Internet traffic and increasing requirement for service quality have made traffic engineering an essential consideration in the operation of large Internet backbone networks. Historically,traffic engineering in the Internet has been hampered by the conventional IP technologies. This article discusses the challenge of Internet Traffic Engineering and the applications of MPLS to traffic engineering in IP networks.

  2. 14 CFR 93.123 - High density traffic airports.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false High density traffic airports. 93.123... (CONTINUED) AIR TRAFFIC AND GENERAL OPERATING RULES SPECIAL AIR TRAFFIC RULES High Density Traffic Airports § 93.123 High density traffic airports. (a) Each of the following airports is designated as a...

  3. 7 CFR 1209.12 - On average.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false On average. 1209.12 Section 1209.12 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS....12 On average. On average means a rolling average of production or imports during the last two...

  4. Analysis of traffic and meteorology on airborne particulate matter in Münster, northwest Germany.

    Science.gov (United States)

    Gietl, Johanna K; Klemm, Otto

    2009-07-01

    The importance of street traffic and meteorological conditions on the concentrations of particulate matter (PM) with an aerodynamic diameter smaller than 10 microm (PM10) was studied in the city of Münster in northwest Germany. The database consisted of meteorological data, data of PM10 mass concentrations and fine particle number (6-225 nm diameter) concentrations, and traffic intensity data as counted with tally hand counters at a four- to six-lane road. On working days, a significant correlation could be found between the diurnal mean PM10 mass concentration and vehicle number. The lower number of heavy-duty vehicles compared with passenger cars contributed more to the particle number concentration on working days than on weekend days. On weekends, when the vehicle number was very low, the correlation between PM10 mass concentration and vehicle number changed completely. Other sources of PM and the meteorology dominated the PM concentration. Independent of the weekday, by decreasing the traffic by approximately 99% during late-night hours, the PM10 concentration was reduced by 12% of the daily mean value. A correlation between PM10 and the particle number concentration was found for each weekday. In this study, meteorological parameters, including the atmospheric stability of the boundary layer, were also accounted for. The authors deployed artificial neural networks to achieve more information on the influence of various meteorological parameters, traffic, and the day of the week. A multilayer perceptron network showed the best results for predicting the PM10 concentration, with the correlation coefficient being 0.72. The influence of relative humidity, temperature, and wind was strong, whereas the influence of atmospheric stability and the traffic parameters was weak. Although traffic contributes a constant amount of particles in a daily and weekly cycle, it is the meteorology that drives most of the variability.

  5. Forecasting Multivariate Road Traffic Flows Using Bayesian Dynamic Graphical Models, Splines and Other Traffic Variables

    NARCIS (Netherlands)

    Anacleto, Osvaldo; Queen, Catriona; Albers, Casper J.

    2013-01-01

    Traffic flow data are routinely collected for many networks worldwide. These invariably large data sets can be used as part of a traffic management system, for which good traffic flow forecasting models are crucial. The linear multiregression dynamic model (LMDM) has been shown to be promising for f

  6. A Behavioural Model of Traffic Congestion: Endogenizing Speed Choice, Traffic Safety and Time Losses

    NARCIS (Netherlands)

    Verhoef, E.T.; Rouwendal, J.

    2004-01-01

    Conventional economic models of traffic congestion assume that the relation between traffic flow and speed is a technical one. This paper develops a behavioural model of traffic congestion, in which drivers optimize their speeds by trading off time costs, expected accident costs and fuel costs. Sinc

  7. THE DEVELOPMENT OF TRAFFIC AND TRAFFIC SAFETY IN SIX DEVELOPED COUNTRIES

    NARCIS (Netherlands)

    OPPE, S

    1991-01-01

    Two models are presented, describing the development of traffic and traffic safety. Traffic volumes, measured by the total amount ofvehicle kilometres per year, are expected to follow a sigmoid saturation curve over time. The logistic function is used to model this development. The fatality rate, th

  8. 77 FR 55439 - Vessel Traffic Service Updates, Including Establishment of Vessel Traffic Service Requirements...

    Science.gov (United States)

    2012-09-10

    ... rulemaking would change the entry for Port Arthur from ``Sabine Traffic'' to ``Port Arthur Traffic'' to more...--003669955: Port Arthur Traffic 156.050 MHz (Ch. 01A)...... The navigable waters of the Sabine-Neches Canal south of 29 52.7' N.; Port Arthur Canal; Sabine Pass Channel; Sabine Bank Channel; Sabine Outer...

  9. Urban traffic noise and the relation to urban density, form, and traffic elasticity

    NARCIS (Netherlands)

    Salomons, E.M.; Berghauser Pont, M.

    2012-01-01

    Traffic noise in cities has serious effects on the inhabitants. Well-known effects are annoyance and sleep disturbance, but long-term health effects such as cardiovascular disease have also been related to traffic noise. The spatial distribution of traffic noise in a city is related to the distribut

  10. Traffic Generator (TrafficGen) Version 1.4.2: Users Guide

    Science.gov (United States)

    2016-06-01

    Headquarters Services , Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202...NOTES 14. ABSTRACT Network science experimentation often requires modeling of realistic network traffic specific to the experiment environment and...the network with Transmission Control Protocol and User Datagram Protocol Internet Protocol traffic. Each node generating network traffic in an

  11. Characteristics of traffic flow at nonsignalized T-shaped intersection with U-turn movements.

    Science.gov (United States)

    Fan, Hong-Qiang; Jia, Bin; Li, Xin-Gang; Tian, Jun-Fang; Yan, Xue-Dong

    2013-01-01

    Most nonsignalized T-shaped intersections permit U-turn movements, which make the traffic conditions of intersection complex. In this paper, a new cellular automaton (CA) model is proposed to characterize the traffic flow at the intersection of this type. In present CA model, new rules are designed to avoid the conflicts among different directional vehicles and eliminate the gridlock. Two kinds of performance measures (i.e., flux and average control delay) for intersection are compared. The impacts of U-turn movements are analyzed under different initial conditions. Simulation results demonstrate that (i) the average control delay is more practical than flux in measuring the performance of intersection, (ii) U-turn movements increase the range and degree of high congestion, and (iii) U-turn movements on the different direction of main road have asymmetrical influences on the traffic conditions of intersection.

  12. Characteristics of Traffic Flow at Nonsignalized T-Shaped Intersection with U-Turn Movements

    Directory of Open Access Journals (Sweden)

    Hong-Qiang Fan

    2013-01-01

    Full Text Available Most nonsignalized T-shaped intersections permit U-turn movements, which make the traffic conditions of intersection complex. In this paper, a new cellular automaton (CA model is proposed to characterize the traffic flow at the intersection of this type. In present CA model, new rules are designed to avoid the conflicts among different directional vehicles and eliminate the gridlock. Two kinds of performance measures (i.e., flux and average control delay for intersection are compared. The impacts of U-turn movements are analyzed under different initial conditions. Simulation results demonstrate that (i the average control delay is more practical than flux in measuring the performance of intersection, (ii U-turn movements increase the range and degree of high congestion, and (iii U-turn movements on the different direction of main road have asymmetrical influences on the traffic conditions of intersection.

  13. Marine Traffic Density Over Port Klang, Malaysia Using Statistical Analysis of AIS Data: A Preliminary Study

    Directory of Open Access Journals (Sweden)

    Masnawi MUSTAFFA

    2016-12-01

    Full Text Available Port Klang Malaysia is the 13th busiest port in the world, the capacity at the port expected to be able to meet the demand until 2018. It is one of the busiest ports in the world and also the busiest port in Malaysia. Even though there are statistics published by Port Klang Authority showing that a lot of ships using this port, this number is only based on ships that entering Port Klang. Therefore, no study has been done to investigate on how dense the traffic is in Port Klang, Malaysia the surrounding sea including Strait of Malacca . This paper has investigated on traffic density over Port Klang Malaysia and its surrounding sea using statistical analysis from AIS data. As a preliminary study, this study only collected AIS data for 7 days to represent daily traffic weekly. As a result, an hourly number of vessels, daily number of vessels, vessels classification and sizes and also traffic paths will be plotted.

  14. Traffic Dynamics of Computer Networks

    CERN Document Server

    Fekete, Attila

    2008-01-01

    Two important aspects of the Internet, namely the properties of its topology and the characteristics of its data traffic, have attracted growing attention of the physics community. My thesis has considered problems of both aspects. First I studied the stochastic behavior of TCP, the primary algorithm governing traffic in the current Internet, in an elementary network scenario consisting of a standalone infinite-sized buffer and an access link. The effect of the fast recovery and fast retransmission (FR/FR) algorithms is also considered. I showed that my model can be extended further to involve the effect of link propagation delay, characteristic of WAN. I continued my thesis with the investigation of finite-sized semi-bottleneck buffers, where packets can be dropped not only at the link, but also at the buffer. I demonstrated that the behavior of the system depends only on a certain combination of the parameters. Moreover, an analytic formula was derived that gives the ratio of packet loss rate at the buffer ...

  15. The effect of bandwidth in scale-free network traffic

    CERN Document Server

    Hu, M B; Wang, W X; Wu, Q S; Wu, Y H; Hu, Mao-Bin; Jiang, Rui; Wang, Wen-Xu; Wu, Qing-Song; Wu, Yong-Hong

    2006-01-01

    We model information traffic on scale-free networks by introducing the bandwidth as the delivering ability of links. We focus on the effects of bandwidth on the packet delivering ability of the traffic system to better understand traffic dynamic in real network systems. Such ability can be measured by a phase transition from free flow to congestion. Two cases of node capacity C are considered, i.e., C=constant and C is proportional to the node's degree. We figured out the decrease of the handling ability of the system together with the movement of the optimal local routing coefficient $\\alpha_c$, induced by the restriction of bandwidth. Interestingly, for low bandwidth, the same optimal value of $\\alpha_c$ emerges for both cases of node capacity. We investigate the number of packets of each node in the free flow state and provide analytical explanations for the optimal value of $\\alpha_c$. Average packets traveling time is also studied. Our study may be useful for evaluating the overall efficiency of networke...

  16. Spinal cord injuries from road traffic crashes in southeastern Iran

    Institute of Scientific and Technical Information of China (English)

    Mohammad R Rasouli; Mohsen Nouri; Vafa Rahimi-Movaghar

    2007-01-01

    Objective: To analyze the data of patients with spinal cord injury (SCI) induced by road traffic crashes in southeastern Iran for better understanding the pattern of these injuries and therefore for better designing health system planning.Methods: In this historical cohort study, the patients who had been transferred to Level I trauma center in southeastern Iran due to road traffic accidents with radiographic documented SCI were evaluated.Results: Among 64 patients with SCI, 38 patients (59.4%, 36 males and 2 females, aged 27.42 years ± 9.44 years on average) were injured by road traffic accidents.Car and motorcycle accidents were responsible for 26 cases (68.4%) and 12 cases (31.6%), respectively. And 31 patients (81. 6%) had complete SCI. Conus medularis (T12-L2) was the most affected level.Conclusions: Results are discussed in terms of preventive measures, specifically those concerning the use of restraint and helmet and driving behavior. This study should be extended nationally to gain a larger case series so that the SCI risk of particular vehicle configurations,considering other crash factors, can be more precisely quantified and the characteristics for low occurrence of SCI can be more precisely identified.

  17. Traffic density determination and its applications using smartphone

    Directory of Open Access Journals (Sweden)

    Al-Sayed Ahmed Al-Sobky

    2016-03-01

    Full Text Available Smartphone is progressively becoming a dominant platform for many transportation applications. This paper introduces a new application for using smartphones to measure traffic density and speed. The proposed system consists of two smartphones and two cars, with observer to count vehicles between the two cars. This count is utilized with tracking data to give “measured” density and “measured” speed. The travel speed and manual traffic counts were used to derive “calculated” density. Measured density was validated against calculated one, and statistical t-test confirmed that the mean difference between two densities is not significant at 5% level. Calculated flow rates were also comparable to actual counts, with an average error of 8.2%. The proposed system was then applied to measure density on 6 of October Elevated Road in Egypt, and the level of service was determined accordingly on 15 road sections studied on this road. Furthermore, actual speed-density data were fitted using exponential model with R2 of 0.85. Advantages of proposed system qualify it for potential applications in developing countries where available resources limit installation of more costly systems. The application of proposed system is limited to daytime, uninterrupted flow conditions, and traffic streams with less percentage of heavy vehicles.

  18. ANALYSING STREET TRAFFIC NOISE POLLUTION IN THE CITY OF YAZD

    Directory of Open Access Journals (Sweden)

    *F. Nejadkoorki, E. Yousefi, F. Naseri

    2010-01-01

    Full Text Available A model is demonstrated that describes street traffic-induced noise pollution in 2008 in Yazd, Iran. Sound levels were measured using a Bruel and Kjaer-2260 sound level meter on 10 streets across the city over this period during the morning rush hour and different vehicle types were counted simultaneously at various sampling points. Geographical Information System was used to generate, store and retrieve the spatial data and map the sound levels using an interpolation technique. The minimum and maximum sound levels appeared to be 70.9 dBA and 80.7 dBA, respectively and these values were above the national legislated norm. Cars and motorcycles were the most commonly used vehicle type in the city, comprising 61.2% and 23.7 % of the total traffic volume, respectively. These data were followed by trucks, buses and bicycles. A number of parameters which were assumed to impact on noise pollution were collected and considered, including geographical position, elevation, the distance to the nearest intersection, street geometry and the numbers of vehicles according to class. The modelling demonstrated that there is a significant relationship between the average sound level and traffic flow (R2 = 0.5. The results showed that although street traffichas increased between 2002 and 2008, the sound levels in the city decreased slightly and this has been attributed to advances in vehicle design.

  19. Mortality in traffic accidents with older adults in Colombia

    Science.gov (United States)

    Cardona, Angela Maria Segura; Arango, Doris Cardona; Fernández, Dedsy Yajaira Berbesí; Martínez, Alejandra Agudelo

    2017-01-01

    ABSTRACT OBJECTIVE To analyze the traffic accident mortality in the Colombian older adults during the 1998-2012 period and show the loss of productive years and mortality from this cause. METHODS Quantitative study of the trend analysis of deaths in Colombia in traffic accidents, from 1998 to 2012, according to death records and population projected by the Colombian National Administrative Department of Statistics. Frequency distribution profile of the deceased, death rates per hundred thousand inhabitants, potential years of life lost and calculation of excess mortality by age in the over 60 were made. RESULTS In the study period 100,758 deaths occurred in traffic accidents, 6,717 annual average, of which 18.5% occurred in people aged 60 years and over. The predominated deaths were men; the risk of dying was 32.15 per hundred thousand people in this age range, with double risk of dying those under 60 years. CONCLUSIONS The young population has a higher proportion of deaths, but those over 60 years are at increased risk of death, leading to the need to turn our gaze to the improvement of road infrastructure and standards, to educate the population in self-care and compliance with safety measures and prepare society for an ever more adult population, more numerous and more prone to take risks.

  20. Perspectives on daily cannabis use:

    DEFF Research Database (Denmark)

    Kronbæk, Mette; Asmussen Frank, Vibeke

    2013-01-01

    of respondents with and without treatment experiences, we were able to compare perspectives on cannabis initiation and trajectories not commonly examined. FINDINGS - All the respondents had started to use cannabis socially as adolescents in the company of peers, using it with specific peer groups...... cannabis use were constructed from the users’ narratives. For some respondents, daily cannabis use in adulthood was an inclusive and non-problematic activity while others described their cannabis use developing into a problematic and exclusive habit. CONCLUSIONS - Trajectories into and continuation...

  1. Managing Hypertriglyceridemia in Daily Practice.

    Science.gov (United States)

    Pramono, Laurentius A; Harbuwono, Dante S

    2015-07-01

    Hypertriglyceridemia is a form of dyslipidemia, which usually occurs in combination with hypercholesterolemia, high-LDL or low-HDL cholesterol level. Most studies suggest that hypertriglyceridemia is associated with many metabolic disorders such as metabolic syndrome, diabetes, obesity, and also cardio-cerebrovascular diseases. Treatment of hypertriglyceridemia is often not comprehensively addressed by many physicians, who usually only include prescribing drugs without encouraging patients to perform physical activity, to take a true healthy diet for dyslipidemia and to stop smoking. This review article discusses evaluation, diagnosis and a comprehensive, yet simple management of hypertriglyceridemia, which can be easily applied in daily clinical practice.

  2. Digital daily cycles of individuals

    DEFF Research Database (Denmark)

    Aledavood, Talayeh; Jørgensen, Sune Lehmann; Saramäki, Jari

    2015-01-01

    Humans, like almost all animals, are phase-locked to the diurnal cycle. Most of us sleep at night and are active through the day. Because we have evolved to function with this cycle, the circadian rhythm is deeply ingrained and even detectable at the biochemical level. However, within the broader...... day-night pattern, there are individual differences: e.g., some of us are intrinsically morning-active, while others prefer evenings. In this article, we look at digital daily cycles: circadian patterns of activity viewed through the lens of auto-recorded data of communication and online activity. We...

  3. Daily practices, consumption and citizenship

    Directory of Open Access Journals (Sweden)

    Jane M. Mazzarino

    2011-12-01

    Full Text Available This paper promotes a reflection on the relationship between daily practices and consumption. Understanding how conflicts, resistance and consensus are generated from daily consumption practices opens up possibilities for reflecting on the construction of sustainability in the context of diversity, one of the landmarks of the globalized world. Within this socio-cultural context, the central issue is: can consumption generate citizenship practices? The concepts of subject and agent help one think about collective action and subjectivation processes and their interferences on the collective consuming behavior. Based on empirical data from a research carried out in the municipality of Estrela in 2007, in the Taquari Valley - Rio Grande do Sul (Southern Brazil on local reality consumption practices, it was possible to conclude that various reasoning mechanisms and values underlie the daily consumption practices. Citizenship construction, based on consumption practices, depends on the subject's reflection capacity on his/her daily practices or on what goes through the circulation of environmental information based on sociability spaces.O artigo reflete sobre as relações entre as práticas cotidianas e o consumo. Compreender como se geram os conflitos, as resistências e os consensos a partir das práticas de consumo no cotidiano abre possibilidades para refletir sobre a construção da sustentabilidade no contexto de diversidade, uma das marcas do mundo globalizado. Neste contexto sociocultural, a questão central que surge é: o consumo pode gerar práticas de cidadania? As noções de sujeito e de agente ajudam a pensar a ação coletiva e os processos de subjetivação e suas interferências no comportamento coletivo de consumir. A partir de dados empíricos da pesquisa realizada em 2007 no município de Estrela, na região do Vale do Taquari - RS (Sul do Brasil, sobre práticas de consumo de uma realidade local, foi possível concluir que

  4. Analytical studies on an extended car following model for mixed traffic flow with slow and fast vehicles

    Science.gov (United States)

    Li, Zhipeng; Xu, Xun; Xu, Shangzhi; Qian, Yeqing; Xu, Juan

    2016-07-01

    The car-following model is extended to take into account the characteristics of mixed traffic flow containing fast and slow vehicles. We conduct the linear stability analysis to the extended model with finding that the traffic flow can be stabilized with the increase of the percentage of the slow vehicle. It also can be concluded that the stabilization of the traffic flow closely depends on not only the average value of two maximum velocities characterizing two vehicle types, but also the standard deviation of the maximum velocities among all vehicles, when the percentage of the slow vehicles is the same as that of the fast ones. With increase of the average maximum velocity, the traffic flow becomes more and more unstable, while the increase of the standard deviation takes negative effect in stabilizing the traffic system. The direct numerical results are in good agreement with those of theoretical analysis. Moreover, the relation between the flux and the traffic density is investigated to simulate the effects of the percentage of slow vehicles on traffic flux in the whole density regions.

  5. Polycyclic aromatic hydrocarbons (PAHs) concentration levels, pattern, source identification and soil toxicity assessment in urban traffic soil of Dhanbad, India.

    Science.gov (United States)

    Suman, Swapnil; Sinha, Alok; Tarafdar, Abhrajyoti

    2016-03-01

    Present study was carried out to assess and understand potential health risk and to examine the impact of vehicular traffic on the contamination status of urban traffic soils in Dhanbad City with respect to polycyclic aromatic hydrocarbons (PAHs). Eight urban traffic sites and two control/rural site surface soils were analyzed and the contents of 13 priority PAHs was determined. Total PAH concentration at traffic sites ranged from 1.019 μg g(-1) to 10.856 μg g(-1) with an average value of 3.488 μg g(-1). At control/rural site, average concentration of total PAHs was found to be 0.640 μg g(-1). PAH pattern was dominated by four- and five-ring PAHs (contributing >50% to the total PAHs) at all the eight traffic sites. On the other hand, rural soil showed a predominance of low molecular weight three-ring PAHs (contributing >30% to the total PAHs). Indeno[123-cd]pyrene/benz[ghi]perylene (IP/BgP) ratio indicated that PAH load at the traffic sites is predominated by the gasoline-driven vehicles. The ratio of Ant/(Ant+Phe) varied from 0.03 to 0.44, averaging 0.10; Fla/(Fla+Pyr) from 0.39 to 0.954, averaging 0.52; BaA/(BaA+Chry) from 0.156 to 0.60, averaging 0.44; and IP/(IP+BgP) from 0.176 to 0.811, averaging 0.286. The results indicated that vehicular emission was the major source for PAHs contamination with moderate effect of coal combustion and biomass combustion. Carcinogenic potency of PAH load in traffic soil was nearly 6.15 times higher as compared to the control/rural soil.

  6. Older Adults with Diabetes and Osteoarthritis and Their Spouses: Effects of Activity Limitations, Marital Happiness, and Social Contacts on Partners' Daily Mood

    Science.gov (United States)

    Roper, Susanne Olsen; Yorgason, Jeremy B.

    2009-01-01

    Using daily diary data from 28 later life couples where one spouse had diabetes and osteoarthritis, we examined crossover effects of target spouses' daily activity limitations and their partners' daily mood. On days when target spouses' daily activity limitations were higher than average, partners' positive mood decreased and negative mood…

  7. Feeding patterns and performance of cows in controlled cow traffic in automatic milking systems.

    Science.gov (United States)

    Melin, M; Svennersten-Sjaunja, K; Wiktorsson, H

    2005-11-01

    Two groups of dairy cows monitored from 3 to 19 wk postpartum were subjected to 2 different cow traffic routines in an automatic milking system with control gates and an open waiting area. Using different time settings in the control gates, the groups of cows were separated by average milking frequency; cows in the high milking frequency routine had a minimum of 4 h between milkings (MF(4)) and were milked 3.2 +/- 0.1 times daily, whereas cows in the low milking frequency routine had at least 8 h between milkings (MF8) and were milked 2.1 +/- 0.1 times daily. Cows in the 2 groups were switched to the opposite milking frequency control for wk 18 and 19. The increased milking frequency resulted in a higher milk yield of about 9% through 16 wk of early lactation Although the higher milk yield was not significant when measured as energy-corrected milk, significant interactions of milking frequency and study period for milk yield and energy-corrected milk yield were consistent with a yield response when cows were milked more frequently. Meal criteria estimated for each individual cow were used to group feeding visits into meals. During MF4, cows fed in fewer meals per day and had longer meals than during MF8. The control gates were used efficiently, with only a few passages not resulting in actual meals. Although the voluntary meal intervals seemed to be short, the average milking frequency was far below that theoretically possible. This was explained by individual differences in milking frequency and long intervals from when a cow was redirected in a control gate until it arrived in the milking unit. A wide individual range in the voluntary interval between the first and the second meal in the milking cycle suggests that fixed time limits for control gates set on group level have no justifiable biological basis. It was also concluded that primiparous cows were well adapted to the automatic milking system after 2 wk in the barn.

  8. A two-lane cellular automaton traffic flow model with the influence of driver, vehicle and road

    Science.gov (United States)

    Zhao, Han-Tao; Nie, Cen; Li, Jing-Ru; Wei, Yu-Ao

    2016-07-01

    On the basis of one-lane comfortable driving model, this paper established a two-lane traffic cellular automata model, which improves the slow randomization effected by brake light. Considering the driver psychological characteristics and mixed traffic, we studied the lateral influence between vehicles on adjacent lanes. Through computer simulation, the space-time diagram and the fundamental figure under different conditions are obtained. The study found that aggressive driver makes a slight congestion in low-density traffic and improves the capacity of high-density traffic, when the density exceeds 20pcu/km the more aggressive drivers the greater the flow, when the density below 40pcu/km driver character makes an effect, the more cautious driver, the lower the flow. The ratio of big cars has the same effect as the ratio of aggressive drivers. Brake lights have the greatest impact on traffic flow and when the density exceeds 10pcu/km the traffic flow fluctuates. Under periodic boundary conditions, the disturbance of road length on traffic is minimal. The lateral influence only play a limited role in the medium-density conditions, and only affect the average speed of traffic at low density.

  9. Upon an issue of correlation between the running speed of vehicles and traffic capacity of a road section

    Science.gov (United States)

    Gaiginschi, L.; Agape, I.

    2016-08-01

    The paper focuses on current algorithms for calculating the traffic capacity of the road sections, provided in various national standards. These algorithms were jointly considering some common groups of factors, such as factors related to the dynamic performance of vehicles and factors related to geometrical - dimensional configuration of the road. The algorithms have particular forms for continuous traffic flow and for discontinuous traffic. As a first stage, there were considered the algorithms for the continuous flows, for which were studied the points of extreme variance for traffic capacity, depending on the running speed. Maximum traffic capacity analytical form for a road section, in continuous traffic flow variant does not depend explicitly of average speed, but allows the evaluation of certain important factors (length section, acceleration at start-up, braking deceleration of vehicles, driver's perception-reaction time, brake friction coefficient, etc.). Consequently, various ways are identified to improve road traffic capacity. The paper justifies reconsideration of the notion of traffic fluence as defined by various national standards; as it stands, the definition of fluency is artificial in relation to the maximum legal speed on that road section, even though the value of that speed is physically impossible.

  10. GPM, TRMM, GMI,TMI Level 3 Daily GPROF Profiling VV03B

    Data.gov (United States)

    National Aeronautics and Space Administration — 3GPROF products provide global gridded monthly/daily precipitation averages from multiple satellites that can be used for climate studies. The 3GPROF products are...

  11. GPM, F16,GMI,SSMI Level 3 Daily GPROF Profiling VV03B

    Data.gov (United States)

    National Aeronautics and Space Administration — 3GPROF products provide global gridded monthly/daily precipitation averages from multiple satellites that can be used for climate studies. The 3GPROF products are...

  12. GPM, METOP-A, GMI,MHS Level 3 Daily GPROF Profiling VV03A

    Data.gov (United States)

    National Aeronautics and Space Administration — 3GPROF products provide global gridded monthly/daily precipitation averages from multiple satellites that can be used for climate studies. The 3GPROF products are...

  13. GPM, F16, GMI,SSMI Level 3 Daily GPROF Profiling VV03A

    Data.gov (United States)

    National Aeronautics and Space Administration — 3GPROF products provide global gridded monthly/daily precipitation averages from multiple satellites that can be used for climate studies. The 3GPROF products are...

  14. GPM, F17,GMI,SSMI Level 3 Daily GPROF Profiling VV03A

    Data.gov (United States)

    National Aeronautics and Space Administration — 3GPROF products provide global gridded monthly/daily precipitation averages from multiple satellites that can be used for climate studies. The 3GPROF products are...

  15. GPM, NOAA18, GMI,MHS Level 3 Daily GPROF Profiling VV03A

    Data.gov (United States)

    National Aeronautics and Space Administration — 3GPROF products provide global gridded monthly/daily precipitation averages from multiple satellites that can be used for climate studies. The 3GPROF products are...

  16. GPM, TRMM, GMI,TMI Level 3 Daily GPROF Profiling VV03A

    Data.gov (United States)

    National Aeronautics and Space Administration — 3GPROF products provide global gridded monthly/daily precipitation averages from multiple satellites that can be used for climate studies. The 3GPROF products are...

  17. GPM, NOAA19, GMI,MHS Level 3 Daily GPROF Profiling VV03B

    Data.gov (United States)

    National Aeronautics and Space Administration — 3GPROF products provide global gridded monthly/daily precipitation averages from multiple satellites that can be used for climate studies. The 3GPROF products are...

  18. GPM, NOAA19, GMI,MHS Level 3 Daily GPROF Profiling VV03A

    Data.gov (United States)

    National Aeronautics and Space Administration — 3GPROF products provide global gridded monthly/daily precipitation averages from multiple satellites that can be used for climate studies. The 3GPROF products are...

  19. GPM, METOP-B, GMI,MHS Level 3 Daily GPROF Profiling VV03A

    Data.gov (United States)

    National Aeronautics and Space Administration — 3GPROF products provide global gridded monthly/daily precipitation averages from multiple satellites that can be used for climate studies. The 3GPROF products are...

  20. GPM, F17,GMI,SSMI Level 3 Daily GPROF Profiling VV03B

    Data.gov (United States)

    National Aeronautics and Space Administration — 3GPROF products provide global gridded monthly/daily precipitation averages from multiple satellites that can be used for climate studies. The 3GPROF products are...

  1. GPM, METOP-A, GMI,MHS Level 3 Daily GPROF Profiling VV03B

    Data.gov (United States)

    National Aeronautics and Space Administration — 3GPROF products provide global gridded monthly/daily precipitation averages from multiple satellites that can be used for climate studies. The 3GPROF products are...

  2. GPM, NOAA18, GMI,MHS Level 3 Daily GPROF Profiling VV03B

    Data.gov (United States)

    National Aeronautics and Space Administration — 3GPROF products provide global gridded monthly/daily precipitation averages from multiple satellites that can be used for climate studies. The 3GPROF products are...

  3. GPM, F18,GMI,SSMI Level 3 Daily GPROF Profiling VV03A

    Data.gov (United States)

    National Aeronautics and Space Administration — 3GPROF products provide global gridded monthly/daily precipitation averages from multiple satellites that can be used for climate studies. The 3GPROF products are...

  4. GPM, F18,GMI,SSMI Level 3 Daily GPROF Profiling VV03B

    Data.gov (United States)

    National Aeronautics and Space Administration — 3GPROF products provide global gridded monthly/daily precipitation averages from multiple satellites that can be used for climate studies. The 3GPROF products are...

  5. GPM, METOP-B, GMI,MHS Level 3 Daily GPROF Profiling VV03B

    Data.gov (United States)

    National Aeronautics and Space Administration — 3GPROF products provide global gridded monthly/daily precipitation averages from multiple satellites that can be used for climate studies. The 3GPROF products are...

  6. Beijing’s Stalled Traffic

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Beijing authorities recently announced the extension of the city’s vehicle restrictions for another year, from April 11, 2009 to April 10, 2010, excluding legal holidays. According to the first round of auto restrictions designed for the Beijing Olympics, private vehicles were banned from roads from 6 a.m. to 9 p.m. daily, alternating

  7. Self-Adaptive Forecasting Method and Its Application in Forecasting Total Telecommunication Service Traffic

    Institute of Scientific and Technical Information of China (English)

    YOU Qin; ZHAO Ying-cai; LI Chun-hao; LIU Guo-liang

    2004-01-01

    The calculating method of Self-Adaptive Forecasting Method (SAFM) is stated in this paper, which is also used in forecasting Total Telecommunication Service Traffic (TTST). It has the advantage that weight selection can be self-adaptive so that it can get better forecasting value compared with the Moving Average Method (MAM) and the Exponential Smoothing Method (ESM).

  8. Calculating Traffic based on Road Sensor Data

    NARCIS (Netherlands)

    Bisseling, Rob; Gao, Fengnan; Hafkenscheid, Patrick; Idema, Reijer; Jetka, Tomasz; Guerra Ones, Valia; Sikora, Monika

    2014-01-01

    Road sensors gather a lot of statistical data about traffic. In this paper, we discuss how a measure for the amount of traffic on the roads can be derived from this data, such that the measure is independent of the number and placement of sensors, and the calculations can be performed quickly for la

  9. Beijing Grapples with1 Traffic Jams2

    Institute of Scientific and Technical Information of China (English)

    慎益

    2004-01-01

    Traffice congestion3 is a prominent4 problem as the number of private cars is soaring5 by more than 1,000 each day in Beijing. In 2003, Beijing recorded about 2000 tragic jams. Traffic management officials complained that "rush hour6" now occupies 12 hours of the day. The city

  10. Formation and Propagation of Local Traffic Jam

    Directory of Open Access Journals (Sweden)

    Hong-sheng Qi

    2013-01-01

    Full Text Available Large scale traffic congestion often stems from local traffic jam in single road or intersection. In this paper, macroscopic method was used to explore the formation and propagation of local traffic jam. It is found that (1 the propagation of traffic jam can be seen as the propagation of traffic signal parameters, that is, virtual split and virtual green time; (2 for a road with endogenous flow, entrance location influences the jam propagation. With the same demand (upstream links flow and entrance flow, the upstream got more influence; (3 when a one-lane road is thoroughly congested, virtual signal parameters everywhere are the same as that at stop line; for a basic road, the virtual signals work in a cooperative manner; (4 phase sequence is one important parameter that influences traffic performances during peak hour where spill back of channelization takes place. The same phase plan for left-turn flow and through flow would be preferred; (5 signal coordination plays an important role in traffic jam propagation and hence effective network signal parameters should be designed to prevent jam from propagation to the whole network. These findings would serve as a basis for future network traffic congestion control.

  11. An analysis of the traffic safety phenomenon.

    NARCIS (Netherlands)

    Asmussen, E. & Kranenburg, A.

    1982-01-01

    The lack of traffic safety is a combination of the critical coincidence of circumstances in the traffic of incidents (near-accidents) and accidents with unwanted (permanent) consequences, such as fatalities, injured and disabled persons and material damage. This definition covers the whole of the cr

  12. Consistency Analysis of Network Traffic Repositories

    NARCIS (Netherlands)

    Lastdrager, Elmer; Pras, Aiko

    2009-01-01

    Traffic repositories with TCP/IP header information are very important for network analysis. Researchers often assume that such repositories reliably represent all traffic that has been flowing over the network; little thoughts are made regarding the consistency of these repositories. Still, for var

  13. SIMPLE LATTICE BOLTZMANN MODEL FOR TRAFFIC FLOWS

    Institute of Scientific and Technical Information of China (English)

    Yan Guangwu; Hu Shouxin

    2000-01-01

    A lattice Boltzmann model with 5-bit lattice for traffic flows is proposed.Using the Chapman-Enskog expansion and multi-scale technique,we obtain the higher-order moments of equilibrium distribution function.A simple traffic light problem is simulated by using the present lattice Boltzmann model,and the result agrees well with analytical solution.

  14. On traffic modelling in GPRS networks

    DEFF Research Database (Denmark)

    Madsen, Tatiana Kozlova; Schwefel, Hans-Peter; Prasad, Ramjee

    2005-01-01

    here are done at the Gi interface. The aim of this paper is to reveal some key statistics of GPRS data applications and to validate if the existing traffic models can adequately describe traffic volume and inter-arrival time distribution for different services. Additionally, we present a method of user...

  15. Traffic Light Detection Using Conic Section Geometry

    Science.gov (United States)

    Hosseinyalmdary, S.; Yilmaz, A.

    2016-06-01

    Traffic lights detection and their state recognition is a crucial task that autonomous vehicles must reliably fulfill. Despite scientific endeavors, it still is an open problem due to the variations of traffic lights and their perception in image form. Unlike previous studies, this paper investigates the use of inaccurate and publicly available GIS databases such as OpenStreetMap. In addition, we are the first to exploit conic section geometry to improve the shape cue of the traffic lights in images. Conic section also enables us to estimate the pose of the traffic lights with respect to the camera. Our approach can detect multiple traffic lights in the scene, it also is able to detect the traffic lights in the absence of prior knowledge, and detect the traffics lights as far as 70 meters. The proposed approach has been evaluated for different scenarios and the results show that the use of stereo cameras significantly improves the accuracy of the traffic lights detection and pose estimation.

  16. Dynamic traffic assignment on parallel computers

    Energy Technology Data Exchange (ETDEWEB)

    Nagel, K.; Frye, R.; Jakob, R.; Rickert, M.; Stretz, P.

    1998-12-01

    The authors describe part of the current framework of the TRANSIMS traffic research project at the Los Alamos National Laboratory. It includes parallel implementations of a route planner and a microscopic traffic simulation model. They present performance figures and results of an offline load-balancing scheme used in one of the iterative re-planning runs required for dynamic route assignment.

  17. Survivable Impairment-Aware Traffic Grooming

    NARCIS (Netherlands)

    Beshir, A.; Nuijts, R.; Malhotra, R.; Kuipers, F.

    2011-01-01

    Traffic grooming allows efficient utilization of network capacity by aggregating several independent traffic streams into a wavelength. In addition, survivability and impairment-awareness (i.e., taking into account the effect of physical impairments) are two important issues that have gained a lot o

  18. GPS queues with heterogeneous traffic classes

    NARCIS (Netherlands)

    Borst, Sem; Mandjes, Michel; Uitert, van Miranda

    2002-01-01

    We consider a queue fed by a mixture of light-tailed and heavy-tailed traffic. The two traffic classes are served in accordance with the generalized processor sharing (GPS) discipline. GPS-based scheduling algorithms, such as weighted fair queueing (WFQ), have emerged as an important mechanism for a

  19. Road traffic noise and incident myocardial infarction

    DEFF Research Database (Denmark)

    Sørensen, Mette; Andersen, Zorana Jovanovic; Nordsborg, Rikke B;

    2012-01-01

    Both road traffic noise and ambient air pollution have been associated with risk for ischemic heart disease, but only few inconsistent studies include both exposures.......Both road traffic noise and ambient air pollution have been associated with risk for ischemic heart disease, but only few inconsistent studies include both exposures....

  20. Floating car data for traffic monitoring

    DEFF Research Database (Denmark)

    Torp, Kristian; Lahrmann, Harry Spaabæk

    2005-01-01

    This paper describes a complete prototype system that uses Floating Car Data (FCD) for both automatic and manual detection of queues in traffic. The system is developed under EU’s Tempo program. The systems consists of small hardware units placed in mobile traffic report units (we use taxis...