Safety evaluation of signalized intersections with left-turn waiting area in China.
Jiang, Xinguo; Zhang, Guopeng; Bai, Wei; Fan, Wenbo
2016-10-01
In recent years the metropolitans in China have seen the surging installations of the left-turn waiting area (LWA) at the signalized intersections. The design allows the left-turning vehicles to enter the intersection at the onset of the through green phase (of the same approach) and wait for the exclusive left-turn signal at the LWA. The LWA layout can effectively reduce the probability of stranded and queue overflow of the left-turn vehicles, but no study is conducted yet to assess the safety performance of the signalized intersections with LWA. The paper adopts the traffic conflict technique (represented by post-encroachment time), compares the discrepancy of conflict types between intersections with LWA and without, and develops the severity models to identify the contributing factors for the left-turn conflicts. Results demonstrate that the left-turn volume, driving outside the LWA, running red light, the presence of secondary conflicts, and the rear-end conflicts significantly increase the severities of traffic conflicts at the LWA. The findings serve to provide recommendations to revise the current design standard of the LWA (GB5768-2009) and consequently improve the safety operations of signalized intersections with LWA in China. Copyright © 2015 Elsevier Ltd. All rights reserved.
Influence of bus stop with left-turn lines between two adjacent signalized intersections
Pang, Ming-Bao; Ye, Lan-Hang; Pei, Ya-Nan
2016-08-01
Based on the symmetric two-lane Nagel-Schreckenberg (STNS) model, a three-lane cellular automaton model between two intersections containing a bus stop with left-turning buses is established in which model the occurrences of vehicle accidents are taken into account. The characteristics of traffic flows with different ratios of left-turn lines are discussed via the simulation experiments. The results indicate that the left-turn lines have more negative effects on capacity, accident rate as well as delay if the stop is located close to the intersections, where the negative effect in a near-side stop is more severe than that in a far-side one. The range of appropriate position for a bus stop without the bottleneck effect becomes more and more narrow with the increase of the ratio of left-turn bus lines. When the inflow is small, a short signal cycle and a reasonable offset are beneficial. When the inflow reaches or exceeds the capacity, a longer signal cycle is helpful. But if the stop position is inappropriate, the increase of cycle fails in reducing the negative effect of left-turning buses and the effectiveness of offset is weakened. Project supported by the National Natural Science Foundation of China (Grant No. 50478088) and the Natural Science Foundation of Hebei Province, China (Grant No. E2015202266).
Modeling Left-Turn Driving Behavior at Signalized Intersections with Mixed Traffic Conditions
Hong Li
2016-01-01
Full Text Available In many developing countries, mixed traffic is the most common type of urban transportation; traffic of this type faces many major problems in traffic engineering, such as conflicts, inefficiency, and security issues. This paper focuses on the traffic engineering concerns on the driving behavior of left-turning vehicles caused by different degrees of pedestrian violations. The traffic characteristics of left-turning vehicles and pedestrians in the affected region at a signalized intersection were analyzed and a cellular-automata-based “following-conflict” driving behavior model that mainly addresses four basic behavior modes was proposed to study the conflict and behavior mechanisms of left-turning vehicles by mathematic methodologies. Four basic driving behavior modes were reproduced in computer simulations, and a logit model of the behavior mode choice was also developed to analyze the relative share of each behavior mode. Finally, the microscopic characteristics of driving behaviors and the macroscopic parameters of traffic flow in the affected region were all determined. These data are important reference for geometry and capacity design for signalized intersections. The simulation results show that the proposed models are valid and can be used to represent the behavior of left-turning vehicles in the case of conflicts with illegally crossing pedestrians. These results will have potential applications on improving traffic safety and traffic capacity at signalized intersections with mixed traffic conditions.
Set methods of left-turn waiting zone at signalized intersection
DING Wei; YANG Xiao-guang; YANG Xiao-long
2009-01-01
To maximize the number of vehicles passing by the stop-line in a cycle and improve the operation ef-ficiency of intersection in China, the settlement of left-turn lane waiting-zone is becoming prevailing. Based on conflicting-point method, the internal mechanism of left-turn flow after stopping line was analyzed through taking postposition left-turn lane waiting-zone intersection for instance. The relationship between the first left-turn vehi-cle and the last vehicle of previous phase passing the conflicting point was expounded. According to the time of successive arriving of two vehicle flows at conflicting-point, the reasonable layout for waiting area of left-turn ve-hicles was researched when the clearance index was less than O. The results suggest that the appropriate layoutfor waiting area of left-turning vehicles can improve the operation efficiency of intersections.
Travel Time Model of Left-Turning Vehicles at Signalized Intersection
Leng Jun-qiang
2012-01-01
Full Text Available The travel time of left-turning vehicles at signalized intersection was discussed. Under the assumption that the opposing through vehicles headway follows M3 distribution, the travel time model was established on the basis of gap theory and queue theory. Comparison was done with the common model based on the assumption that the opposing through vehicles headway follows negative exponential distribution. The results show that the model in this paper has stronger applicability and its most relative error is less than 15%. In addition, the sensitivity analysis was done. The results show that the opposing through flow rate has significant impact on travel time. The impact of left-turning flow rate and following headway is light when the opposing through flow rate is small, the threshold is about 0.18 veh/s. The model established in this paper can well calculate travel time of left-turning vehicles at intersection, and the methodology may provide reference to other occasions.
Pedestrian safety under permissive left-turn signal control
Yi Qi
2017-06-01
Full Text Available At intersections with permissive only signal control, pedestrians will move at the phase with the parallel through vehicular movement and the permissive left-turn movement. The left-turn vehicles have to yield to both opposing vehicles and pedestrians at the crosswalk. Under such complicated driving conditions, collision risks rise if left-turn vehicles make misjudgments and fail to yield to the pedestrians. In this research, driving-simulation based experiments were conducted for identifying and assessing the impacts of the factors that contribute to the collision between the left-turn vehicles and the pedestrians during the permissive left-turn phase. The results of this study showed that the percentage of left-turn trucks and the pedestrian volume has significant impacts on the pedestrian safety under permissive left-turn signal control.
Hasina Iasmin
2016-07-01
Full Text Available Pedestrians are the most vulnerable road users as they are more exposed than other road users. Pedestrian safety at road intersections still remains the most vital and yet unsolved issue. One of the critical points in pedestrian safety is the occurrence of accidents between left-turning vehicle and pedestrians on crosswalks at signalized intersections. A crosswalk is a place designated for pedestrians and cyclists to cross vehicular roads safely. Drivers are expected to give priority to pedestrians or cyclists during interactions between them on the crosswalk. If a driver exhibits non-yielding behavior, the interaction will turn into a collision. This study examined the safety effect of three crosswalks designed with different materials such as red-colored material or brick pavement based on a safety performance study. The safety performance study considered left-turning driver's gap acceptance behavior and the severity of traffic conflict events between left-turning vehicles and pedestrians. The results of the study indicates that using brick pavement on a crosswalk increases the safety level of the crosswalk. Drivers at such crosswalks are more acquiescent to the priority rule.
Safety evaluation of intersections with dynamic use of exit-lanes for left-turn using field data.
Zhao, Jing; Liu, Yue
2017-03-01
As a newly proposed unconventional intersection design, the exit-lanes for left-turn (EFL) intersection is found to be effective in increasing the intersection capacity with high level of application flexibility, especially under heavy left-turn traffic conditions. However, the operational safety of EFL is of most concern to the authority prior to its implementation. This paper evaluates the safety of the EFL intersections by studying the behavior of left-turn maneuvers using field data collected at 7 locations in China. A total of 22830 left-turn vehicles were captured, in which 9793 vehicles turned left using the mixed-usage area. Four potential safety problems, including the red-light violations, head-on collision risks, trapped vehicles, and rear-end crash risks, were discussed. Statistical analyses were carried out to compare the safety risk between the EFL intersection and the conventional one. Results indicate that the safety problems of EFL intersections mainly lie in higher percentages in red-light violations at the pre-signal (1.83% higher), wrong-way violation problems during the peak hours (the violation rate reaches up to 11.07%), and the lower travel speeds in the mixed-usage area (18.75% lower). Such risks can be counteracted, however, by providing more guiding information, installing cameras to investigate and punish violation maneuvers, and adjusting design parameter values for layout design and signal timing, respectively.
Safety effects of traffic signing for left turn flashing yellow arrow signals.
Schattler, Kerrie L; Gulla, Cody J; Wallenfang, Travis J; Burdett, Beau A; Lund, Jessica A
2015-02-01
In 2010, the left turn flashing yellow arrow (FYA) signal displays were installed at signalized intersections on state routes in the Peoria, Illinois, area. Supplemental traffic signs with text "Left Turn Yield on Flashing Yellow Arrow" were mounted on the mast arm adjacent to the left turn signal at over half of the FYA installations. The purpose of this paper is to present the results of the effectiveness evaluation of the FYA supplemental sign on safety. Analyses are presented on the effects of the FYA supplemental sign for all drivers and a subset of drivers age 65 and older. A crash-based comparison of 164 FYA approaches including 90 approaches with the sign and 74 approaches without the sign showed greater crash reductions when the supplemental FYA sign was present. The results also showed that crashes involving drivers age 65 and older did not experience the same magnitudes of crash reductions as compared to all drivers. The findings of this research indicate that supplemental FYA signs may help in improving safety for left-turning vehicles during the permissive interval. Thus, it is recommended that supplemental signs be used when initially implementing the FYA, and that effort to educate the driving public on new traffic control be made to further improve safety at signalized intersections. Copyright © 2014. Published by Elsevier Ltd.
Safety of the Las Vegas left-turn display.
Ozmen, Ozlem; Tian, Zong Z; Gibby, A Reed
2014-01-01
This paper provides a safety evaluation of a special protected/permitted left turn signal control (Las Vegas LT Display) that has been implemented in the urbanized area of Las Vegas, Nevada. The Las Vegas LT Display eliminates the yellow trap condition for leading approach in lead/lag operation. It provides protected only left turns during certain times of day by suppressing the permitted green ball and yellow ball displays. Before and after studies were conducted using the crash data from 10 intersections. Results from the analyses indicated that no obvious safety concerns due to use of the special display. Copyright © 2013 Elsevier Ltd. All rights reserved.
Crash patterns at signalized intersections
Polders, Evelien; Daniels, Stijn; HERMANS, Elke; Brijs, Tom; Wets, Geert
2015-01-01
Traffic signals are often implemented to provide for efficient movement and to improve traffic safety. Nevertheless, severe crashes still occur at signalized intersections. This study aims to improve the understanding of signalized intersection safety by identifying crash types, locations and factors associated with signalized intersections. For this purpose, 1295 police-reported crashes at 87 signalized intersections are analyzed based on detailed crash descriptions, i.e. crash data and c...
Infiuence of Bicycle Traffic on Capacity of Typical Signalized Intersection
CHEN Xiaoming; SHAO Chunfu; YUE Hao
2007-01-01
Bicycle traffic has a significant effect on the capacity of signalized intersections. This paper divides the influence of bicyclists on vehicular flow into four types with the time durations estimated based on probability, shock wave, and gap acceptance theory. Vehicular saturation flow rate is predicted for various conditions on the basis of the speed-flow curve for the capacity of typical intersections influenced by bicycle traffic.The model overcomes the limitations of the Highway Capacity Manual (HCM, 2000) method for left-turns due to data collection, and takes into account the effect of trapped bicycles on the through vehicular traffic.The numerical results show that the left-turn and through capacities predicted by the model are lower than those of the HCM method. The right-turn capacity is close to that of the HCM method at Iow bicycle volumes and higher than that of the HCM method at high bicycle volumes.
Left-turn phase: permissive, protected, or both? A quasi-experimental design in New York City.
Chen, Li; Chen, Cynthia; Ewing, Reid
2015-03-01
The practice of left-turn phasing selection (permissive, protected-only, or both) varies from one locality to another. The literature evidence on this issue is equally mixed and insufficient. In this study, we evaluate the safety impacts of changing left-turn signal phasing from permissive to protected/permissive or protected-only at 68 intersections in New York City using a rigorous quasi-experimental design accompanied with regression modeling. Changes in police reported crashes including total crashes, multiple-vehicle crashes, left-turn crashes, pedestrian crashes and bicyclist crashes were compared between before period and after period for the treatment group and comparison group by means of negative binomial regression using a Generalized Estimating Equations (GEE) technique. Confounding factors such as the built environment characteristics that were not controlled in comparison group selection are accounted for by this approach. The results show that the change of permissive left-turn signal phasing to protected/permissive or protected-only signal phasing does not result in a significant reduction in intersection crashes. Though the protected-only signal phasing does reduce the left-turn crashes and pedestrian crashes, this reduction was offset by a possible increase in over-taking crashes. These results suggest that left-turn phasing should not be treated as a universal solution that is always better than the permissive control for left-turn vehicles. The selection and implementation of left-turn signal phasing needs to be done carefully, considering potential trade-offs between safety and delay, and many other factors such as geometry, traffic flows and operations. Copyright © 2014 Elsevier Ltd. All rights reserved.
Urban Intersection Traffic Signal Control Based on Fuzzy Logic
魏武; 张毅; 张佐; 宋靖雁
2002-01-01
This paper presents a fuzzy logic adaptive traffic signal control method for an isolated four-approach intersection with through and left-turning movements. In the proposed method, the fuzzy logic controller can make adjustments to signal timing in response to observed changes. The "urgency degree" term that can describe different user's demands for a green light is used in the fuzzy logic decision-making. In addition, a three-level fuzzy controller model decides whether to extend or terminate the current signal phase and the sequence of phases. Simulation results show that the fuzzy controller can adjust its signal timing in response to changing traffic conditions on a real-time basis and that the proposed fuzzy logic controller leads to less vehicle delays and a lower percentage of stopped vehicles.
Modelling of urban traffic networkof signalized intersections
2013-01-01
This report presents how traffic network of signalized intersection in a chosen urban area called Tema is synchronized. Using a modular approach, two different types of traffic intersection commonly found in an urban area were modelled i.e. a simple intersection and a complex intersection. A direct road, even though not an intersection, was also included in the modelling because it’s commonly found in an urban area plus it connects any two intersections. Each of these scenarios was modelled u...
Phase diagram of a non-signalized T-shaped intersection
Echab, H.; Lakouari, N.; Ez-Zahraouy, H.; Benyoussef, A.
2016-11-01
In this paper, we investigated a non-signalized T-shaped intersection using the cellular automata model under the open boundary condition. Two different priority rules at intersection are introduced (Rule 1, Rule 2) to eliminate the jam-packed state. Phase diagram and its variation with the ratios of right and/or left turning vehicles are investigated. The space-time and the density profiles are also studied. The simulation results indicate that the system does not show the same performance under different priority rules, where Rule 1 (resp. Rule 2) can be better than Rule 2 (resp. Rule 1) according to the ratios of turning vehicles.
交通禁左理论浅析%Analysis on the Left-turn Prohibition
李艳艳
2011-01-01
This paper studied the left-turn prohibition of urban traffic management,and analyzed the traffic feature of left turn traffic which has the most influence on the intersection.Then the consequence of left-turn prohibition was discussed from the pros and cons,and this paper introduces the suitable intersection traffic condition for left-turn prohibition,on this basis,the common ways of left-turn prohibition were summarized.Finally,this paper presents implementation of left-turn prohibition considered more than just traffic condition of single intersection,and also the impact of close link and intersection caused by left-turn prohibition.This paper have an important significance on solving the urban traffic problem.%研究城市交通组织管理的禁左理论,分析对交叉口影响最大的左转车流的特性,并采用常用的禁左方式,最后指出实施禁左不仅要考虑到单个交叉口的交通条件,还要考虑到对临近路段和交叉口的影响。
Opposed turns at signalized intersections
Akcelik, R.
1989-06-01
The 1985 Highway Capacity Manual (HCM) brought the U.S. and Australian methodologies for signalized intersections closer together. An important element in this methodology is the techniques used for the estimation of opposed (permissive) turn saturation flows. Although the basic modeling philosophies of the HCM and Australian methods are similar, there are significant differences in the procedures used and therefore in the results from the two methods. In particular, the latest methodology employed in the SIDRA software has eliminated the use of opposed turn adjustment factors for lane groups and adopted an explicit and direct method of modeling individual lanes. The purpose of this paper is to bring these new methods to the attention of the U.S. researchers since it is understood that efforts are being made to improve the 1985 HCM method.
Bie, Yiming; Wang, Yinhai
2017-01-01
To deal with the conflicts between left-turn and through traffic streams and increase the discharge capacity, this paper addresses the pre-signal which is implemented at a signalized intersection. Such an intersection with pre-signal is termed as a tandem intersection. For the tandem intersection, phase swap sorting strategy is deemed as the most effective phasing scheme in view of some exclusive merits, such as easier compliance of drivers, and shorter sorting area. However, a major limitation of the phase swap sorting strategy is not considered in previous studies: if one or more vehicle is left at the sorting area after the signal light turns to red, the capacity of the approach would be dramatically dropped. Besides, previous signal control studies deal with a fixed timing plan that is not adaptive with the fluctuation of traffic flows. Therefore, to cope with these two gaps, this paper firstly takes an in-depth analysis of the traffic flow operations at the tandem intersection. Secondly, three groups of loop detectors are placed to obtain the real-time vehicle information for adaptive signalization. The lane selection behavior in the sorting area is considered to set the green time for intersection signals. With the objective of minimizing the vehicle delay, the signal control parameters are then optimized based on a dynamic programming method. Finally, numerical experiments show that average vehicle delay and maximum queue length can be reduced under all scenarios. PMID:28531198
Jin, Cheng-Jie; Wang, Wei; Jiang, Rui
2016-08-01
The proper setting of traffic signals at signalized intersections is one of the most important tasks in traffic control and management. This paper has evaluated the four-phase traffic signal plans at a four-leg intersection via cellular automaton simulations. Each leg consists of three lanes, an exclusive left-turn lane, a through lane, and a through/right-turn lane. For a comparison, we also evaluate the two-phase signal plan. The diagram of the intersection states in the space of inflow rate versus turning ratio has been presented, which exhibits four regions: In region I/II/III, congestion will propagate upstream and laterally and result in queue spillover with both signal plans/two-phase signal plan/four-phase signal plan, respectively. Therefore, neither signal plan works in region I, and only the four-phase signal plan/two-phase signal plan works in region II/III. In region IV, both signal plans work, but two-phase signal plan performs better in terms of average delays of vehicles. Finally, we study the diagram of the intersection states and average delays in the asymmetrical configurations.
Information point and saturation flow at signalized intersections
Lijun Gao
2016-08-01
Full Text Available This paper introduces an information point factor and attempts to identify how it affects saturation flow and their relationship at signalized intersections. An information point is defined as any object, structure, or activity located outside of a traveling vehicle that can potentially attract the visual attention of the driver. Saturation flow rates are studied at three pairs of signalized intersections in Toledo, Ohio, USA. Each pair of intersections consists of one intersection with a high number of information points and one intersection with a low number of information points. Study results reveal that, for each pair of intersections, the one with high information points has a lower saturation flow rate than the one with low information points. A statistical analysis shows that the differences are significant. Based on the saturation flow data of the paired intersections, information point effect models are developed and presented in this paper.
Characteristics of turn signal use at intersections in baseline naturalistic driving.
Sullivan, John M; Bao, Shan; Goudy, Roy; Konet, Heather
2015-01-01
The purpose of this study was to determine whether a driver's use of turn signals is sufficiently reliable to forecast a vehicle's future path around an intersection, when detailed information about the intersection is unavailable. Naturalistic observations of turn signal use among 108 drivers on surface streets were extracted from the baseline portion of a field operational test of a safety system. Left and right turns that resulted in heading changes of between 70 and 110° and turn radii between 18 and 90 m were selected from the dataset. The odds that a driver would signal a turn were modeled as a function of road type, turn direction, presence of a forward vehicle, whether the vehicle stopped before the turn, and driver age and gender. Overall, 25 percent of left turns and 29 percent of right turns were not signaled. Road type, turn direction, and presence of a forward vehicle were found to influence the odds that a turn is signaled, while gender and age of the driver did not. The results suggest that situational factors like road type and turn direction are more powerful predictors of whether a turn will be signaled than either age or gender. Signaling on major and minor surface roads was about 5 times more likely than on local roads and 1.5 times more likely when a forward vehicle was present, suggesting a possible effect of traffic volume. It was concluded that turn signal activation alone may be insufficiently reliable to forecast a driver's path. Copyright © 2014 Elsevier Ltd. All rights reserved.
Simulation of Intersection Rivet at Non-signalized Intersection in Housing Scheme
Nazmi, Mohd; Takaba, Sadao; Ohno, Sumio; Yusoff, Mohd Nazaruddin
Accident in the residential area are become serious case in Malaysia. Most of the incidents occur among pedestrians, bicycles, motorcycles and vehicles. Our research purpose is to avoid collision at the non-signalized intersection in the housing scheme. We committed to reduce injuries and increase pedestrians' safety. Our research provides important information that can help driver predict common problems and take steps to prevent collisions. Intersection rivet is proposed for this matter. This type of signal system can prevent any accident in a dangerous non-signalized intersection. Simulation tools and systems are developed to find and solve the problem in order to decrease any fatal incident. Investigation data were used to simulate the situation more precisely. The result will be effective as reference to set the parameter of control system of the intersection rivet.
Simulation of queue with cyclic service in signalized intersection system
Muhammad Dermawan Mulyodiputro
2015-03-01
Full Text Available The simulation was implemented by modeling the queue with cyclic service in the signalized intersection system. The service policies used in this study were exhaustive and gated, the model was the M/M/1 queue, the arrival rate used was Poisson distribution and the services rate used was Exponential distribution. In the gated service policy, the server served only vehicles that came before the green signal appears at an intersection. Considered that there were 2 types of exhaustive policy in the signalized intersection system, namely normal exhaustive (vehicles only served during the green signal was still active, and exhaustive (there was the green signal duration addition at the intersection, when the green signal duration at an intersection finished. The results of this queueing simulation program were to obtain characteristics and performance of the system, i.e. average number of vehicles and waiting time of vehicles in the intersection and in the system, as well as system utilities. Then from these values, it would be known which of the cyclic service policies (normal exhaustive, exhaustive and gated was the most suitable when applied to a signalized intersection system
Chai, C; Wong, Y D
2014-02-01
At intersection, vehicles coming from different directions conflict with each other. Improper geometric design and signal settings at signalized intersection will increase occurrence of conflicts between road users and results in a reduction of the safety level. This study established a cellular automata (CA) model to simulate vehicular interactions involving right-turn vehicles (as similar to left-turn vehicles in US). Through various simulation scenarios for four case cross-intersections, the relationships between conflict occurrences involving right-turn vehicles with traffic volume and right-turn movement control strategies are analyzed. Impacts of traffic volume, permissive right-turn compared to red-amber-green (RAG) arrow, shared straight-through and right-turn lane as well as signal setting are estimated from simulation results. The simulation model is found to be able to provide reasonable assessment of conflicts through comparison of existed simulation approach and observed accidents. Through the proposed approach, prediction models for occurrences and severity of vehicle conflicts can be developed for various geometric layouts and traffic control strategies.
Qing Li
2016-08-01
Full Text Available Due to sun glare disturbances, drivers encounter fatal threats on roadways, particularly at signalized intersections. Many studies have attempted to develop applicable solutions, such as avoiding sun positions, applying road geometric re-directions, and wearing anti-glare glasses. None of these strategies have fully solved the problem. As one of the “Connected Vehicle” practices proposed by the U.S. Department of Transportation, advanced warning messages (AWMs are capable of providing wireless information about traffic controls. AWM acts as a supplement to conventional signs and signals, which can be blocked by obstacles or natural disturbances, such as sun glare. The drivers' smart advisory system (DSAS can provide drivers with AWM. Using a driving simulator this research explores the effects of DSAS messages on driving behaviors under sun glare disturbance. Statistical analyses were applied to assess (1 the negative impacts of sun glare, (2 the compensation of the DSAS AWM to sun glare effects, and (3 the improvement in driving performance due to DSAS AWM. Four performance indexes were measured, including (1 half kinetic energy speed, (2 mean approach speed, (3 brake response time, and (4 braking distance. The effects of the socio-demographic factors, such as gender, age, educational background, and driving experience were also studied. The analytical results illustrate that the DSAS can compensate for reduced visibility due to sun glare and improve driving performance to a normal visual situation, particularly for left turn and through movement.
Modeling signalized intersection safety with corridor-level spatial correlations.
Guo, Feng; Wang, Xuesong; Abdel-Aty, Mohamed A
2010-01-01
Intersections in close spatial proximity along a corridor should be considered as correlated due to interacted traffic flows as well as similar road design and environmental characteristics. It is critical to incorporate this spatial correlation for assessing the true safety impacts of risk factors. In this paper, several Bayesian models were developed to model the crash data from 170 signalized intersections in the state of Florida. The safety impacts of risk factors such as geometric design features, traffic control, and traffic flow characteristics were evaluated. The Poisson and Negative Binomial Bayesian models with non-informative priors were fitted but the focus is to incorporate spatial correlations among intersections. Two alternative models were proposed to capture this correlation: (1) a mixed effect model in which the corridor-level correlation is incorporated through a corridor-specific random effect and (2) a conditional autoregressive model in which the magnitude of correlations is determined by spatial distances among intersections. The models were compared using the Deviance Information Criterion. The results indicate that the Poisson spatial model provides the best model fitting. Analysis of the posterior distributions of model parameters indicated that the size of intersection, the traffic conditions by turning movement, and the coordination of signal phase have significant impacts on intersection safety.
刘广萍; 丁建梅
2004-01-01
Vehicle delay is an important measure to evaluate the signal timings of signalized intersections.When optimization the signal control parameters, delays of vehicles from all approach directions of an intersection should be considered. Based on the analysis of the vehicle delay on an approach of intersection, directed against the typical condition of a congested intersection-over-saturated condition, the paper has analyzed and inferred the intersection delay dynamic formulation, and has established the relation between intersection delay,the signal timings, vehicle arrival rate and the queue lengths, and that provides useful information for understanding vehicle delay of signalized intersection and for establishing performance index function of signal timing optimization.
Research on Driver Behavior in Yellow Interval at Signalized Intersections
Zhaosheng Yang
2014-01-01
Full Text Available Vehicles are often caught in dilemma zone when they approach signalized intersections in yellow interval. The existence of dilemma zone which is significantly influenced by driver behavior seriously affects the efficiency and safety of intersections. This paper proposes the driver behavior models in yellow interval by logistic regression and fuzzy decision tree modeling, respectively, based on camera image data. Vehicle’s speed and distance to stop line are considered in logistic regression model, which also brings in a dummy variable to describe installation of countdown timer display. Fuzzy decision tree model is generated by FID3 algorithm whose heuristic information is fuzzy information entropy based on membership functions. This paper concludes that fuzzy decision tree is more accurate to describe driver behavior at signalized intersection than logistic regression model.
Modeling Traffic Flow and Management at Un-signalized, Signalized and Roundabout Road Intersections
R. Kakooza
2005-01-01
Full Text Available Traffic congestion continues to hinder economic and social development and also has a negative impact on the environment. A simple mathematical model is used to analyze the different types of road intersections in terms of their Performance in relation to managing traffic congestion and to establish the condition for stability of the road intersections after sufficiently longer periods of time (steady-state. In the analysis, single and double lane un-signalized, signalized and roundabout intersections are evaluated on the basis of their performance (expected number of vehicles and waiting time. Experimental scenarios are carefully designed to analyze the performance of the different types of intersections. It is noted that under light traffic, roundabout intersections perform better than un-signalized and signalized in terms of easing congestion. However under heavy traffic, signalized intersection perform better in terms of easing traffic congestion compared to un-signalized and roundabout intersections. It is further noted that for stability of a road intersection, the proportion of the time a road link stopping at an intersection is delayed should not exceed the utilization factor (the ratio of the arrival rate of vehicles to the product of number of service channels and service rate.
Augmented reality cues to assist older drivers with gap estimation for left-turns.
Rusch, Michelle L; Schall, Mark C; Lee, John D; Dawson, Jeffrey D; Rizzo, Matthew
2014-10-01
The objective of this study was to assess the effects of augmented reality (AR) cues designed to assist middle-aged and older drivers with a range of UFOV impairments, judging when to make left-turns across oncoming traffic. Previous studies have shown that AR cues can help middle-aged and older drivers respond to potential roadside hazards by increasing hazard detection without interfering with other driving tasks. Intersections pose a critical challenge for cognitively impaired drivers, prone to misjudge time-to-contact with oncoming traffic. We investigated whether AR cues improve or interfere with hazard perception in left-turns across oncoming traffic for drivers with age-related cognitive decline. Sixty-four middle-aged and older drivers with a range of UFOV impairment judged when it would be safe to turn left across oncoming traffic approaching the driver from the opposite direction in a rural stop-sign controlled intersection scenario implemented in a static base driving simulator. Outcome measures used to evaluate the effectiveness of AR cueing included: Time-to-Contact (TTC), Gap Time Variation (GTV), Response Rate, and Gap Response Variation (GRV). All drivers estimated TTCs were shorter in cued than in uncued conditions. In addition, drivers responded more often in cued conditions than in uncued conditions and GRV decreased for all drivers in scenarios that contained AR cues. For both TTC and response rate, drivers also appeared to adjust their behavior to be consistent with the cues, especially drivers with the poorest UFOV scores (matching their behavior to be close to middle-aged drivers). Driver ratings indicated that cueing was not considered to be distracting. Further, various conditions of reliability (e.g., 15% miss rate) did not appear to affect performance or driver ratings.
Vehicular headways on signalized intersections: theory, models, and reality
Krbálek, Milan; Šleis, Jiří
2015-01-01
We discuss statistical properties of vehicular headways measured on signalized crossroads. On the basis of mathematical approaches, we formulate theoretical and empirically inspired criteria for the acceptability of theoretical headway distributions. Sequentially, the multifarious families of statistical distributions (commonly used to fit real-road headway statistics) are confronted with these criteria, and with original empirical time clearances gauged among neighboring vehicles leaving signal-controlled crossroads after a green signal appears. Using three different numerical schemes, we demonstrate that an arrangement of vehicles on an intersection is a consequence of the general stochastic nature of queueing systems, rather than a consequence of traffic rules, driver estimation processes, or decision-making procedures.
Safety Impacts of the Actuated Signal Control at Urban Intersections
Sang Hyuk Lee
2016-02-01
Full Text Available To reduce travel time, the actuated signal controls have been implemented at urban intersections. However, the safety impacts of actuated signal controls thus far have rarely been examined. In this assessment of the safety impact of urban intersections with semi-actuated signal controls, the safety performance functions and EB approaches were applied. The semi-actuated signal controls have increased injuries and total crashes in all crash types by around 5.9% and 3.8%, respectively. Regarding the most common crash types, such as angle, sideswipe & rear-end, and head-on crashes, semi-actuated signal controls have been seen to decrease injuries by 7.7%. Total crashes have been reduced by over 9.2% through the use of semi-actuated signal controls. This may be result of optimal signal timings considering traffic conditions during peak time periods. In conclusion, safety impact factors which have been established in this study can be used to improve safety and minimize travel times using semi-actuated signal controls.
Road Impedance Model Study under the Control of Intersection Signal
Yunlin Luo
2015-01-01
Full Text Available Road traffic impedance model is a difficult and critical point in urban traffic assignment and route guidance. The paper takes a signalized intersection as the research object. On the basis of traditional traffic wave theory including the implementation of traffic wave model and the analysis of vehicles’ gathering and dissipating, the road traffic impedance model is researched by determining the basic travel time and waiting delay time. Numerical example results have proved that the proposed model in this paper has received better calculation performance compared to existing model, especially in flat hours. The values of mean absolute percentage error (MAPE and mean absolute deviation (MAD are separately reduced by 3.78% and 2.62 s. It shows that the proposed model has feasibility and availability in road traffic impedance under intersection signal.
The Research of Vehicle Acceleration at Signalized Intersections
Vuk Bogdanović
2013-02-01
Full Text Available Vehicle acceleration is an important parameter used in planning various road elements, traffic signalization, geometric elements of an intersection, signal plans of traffic lights, etc. The knowledge of vehicle acceleration values is also necessary in using simulation softwares for more accurate analysis of the total situation at an intersection, on a road section or in a traffic network. In a lot of earlier studies, acceleration values were analysed and defined, mostly in optimal conditions for traffic functioning. However, values of almost all traffic flow parameters have been changed over time, due to changes in driving-dynamic vehicle characteristics, pneumatic tyres, material used for building road surface, etc. Besides, local environment influence and changes in drivers’ behaviour also significantly affect values of this parameter. According to HCM, it is advisable to perform local research for all values of the parameters recommended within the framework of this handbook, and to adapt their values to local conditions as well. The results of measuring the values of vehicles acceleration at signalized intersections in Novi Sad, Serbia, have been shown in this paper, using the procedure based on video recording processing.
A mathematical model of traffic noise at a signalized intersection
Sorawit Narupiti
2005-05-01
Full Text Available This research aims at modeling interrupted flow traffic noise at a signalized intersection. The models are mathematically derived by applying the inverse square law of sound pressure incorporating with theories of traffic flow at an intersection. The traffic flow theories utilized for developing the model consist of characteristics of individual vehicle motion at intersection, shock wave model, and queuing analysis. The modelformulation is divided into two different approaches and takes into account of all regimes of vehicle movement while traversing an intersection (i.e. idling, decelerating, accelerating, and cruising conditions. The first approach assumes a constant acceleration/deceleration rate for each type of vehicle. Another appliesinconstant acceleration/deceleration which comes from speed-distance relationship. The final models are expressed in LAeq (1 hr.Eventually, the developed models are validated by collecting equivalent continuous noise level in 1 min as well as traffic parameters (i.e. red time, number of vehicle in the queue, queue length, time of queue dissipation, and final cruise speed from fifteen vehicle platoons. The noise levels predicted from the developed models are compared with the measured ones. The results show that the inconstant acceleration model gives the predicted levels closer to the measured ones than constant acceleration model. The error of inconstant acceleration model ranges from 0.1-3.9 dB(A with the average value of 2 dB(A overestimated and that of constant acceleration model ranges from 1.8-6.5 dB(A with the average value of 3 dB(A underestimated. It might be concluded that movement characteristic of vehicle is an important factor that apparently affects the accuracy of traffic noise prediction at an intersection.
A Comparison of Tram Priority at Signalized Intersections
Zhang, Lele
2013-01-01
We study tram priority at signalized intersections using a stochastic cellular automaton model for multimodal traffic flow. We simulate realistic traffic signal systems, which include signal linking and adaptive cycle lengths and split plans, with different levels of tram priority. We find that tram priority can improve service performance in terms of both average travel time and travel time variability. We consider two main types of tram priority, which we refer to as full and partial priority. Full tram priority is able to guarantee service quality even when traffic is saturated, however, it results in significant costs to other road users. Partial tram priority significantly reduces tram delays while having limited impact on other traffic, and therefore achieves a better result in terms of the overall network performance. We also study variations in which the tram priority is only enforced when trams are running behind schedule, and we find that those variations retain almost all of the benefit for tram op...
Multinomial Logit Model of Pedestrian Crossing Behaviors at Signalized Intersections
Zhu-Ping Zhou
2013-01-01
Full Text Available Pedestrian crashes, making up a large proportion of road casualties, are more likely to occur at signalized intersections in China. This paper aims to study the different pedestrian behaviors of regular users, late starters, sneakers, and partial sneakers. Behavior information was observed manually in the field study. After that, the survey team distributed a questionnaire to the same participant who has been observed, to acquire detailed demographic and socioeconomic characteristics as well as attitude and preference indicators. Totally, 1878 pedestrians were surveyed at 16 signalized intersections in Nanjing. First, correlation analysis is performed to analyze each factor’s effect. Then, five latent variables including safety, conformity, comfort, flexibility, and fastness are obtained by structure equation modeling (SEM. Moreover, based on the results of SEM, a multinomial logit model with latent variables is developed to describe how the factors influence pedestrians’ behavior. Finally, some conclusions are drawn from the model: (1 for the choice of being late starters, arrival time, the presence of oncoming cars, and crosswalk length are the most important factors; (2 gender has the most significant effect on the pedestrians to be sneakers; and (3 age is the most important factor when pedestrians choose to be partial sneakers.
Halim CEYLAN
2007-02-01
Full Text Available This study develops approximate mathematical expressions for delay components at signalized intersections. Delay components are solved with the coordinate transformation method. The performance indicators for the signalized intersection are determined as an oversaturated and under saturated cases. During the analysis, the steady-state and the deterministic queuing theory are investigated first, and then time-dependent transformation is made. Developed model, called YHM, is applied to an example signalized intersection. Results are compared with the current situation and the Webster method. YHM is improved the intersection performance by about 500 % for this example. Moreover, signal parameters are significantly differs from the current and Webster signal control.
Capacity Reliability of Signalized Intersections with Mixed Traffic Conditions
CHEN Xiaoming; SHAO Chunfu; LI Da; DONG Chunjiao
2009-01-01
The reliability of capacity of signalized intersections in mixed traffic conditions involving vehicles, bicycles, and pedestrians was investigated to complete the conventional, deterministic capacity calculations. Simulations using VISSIM provided estimates of capacity distributions, and demonstrated the effects of the analysis intervals on the distributions. With the random vehicle arrivals taken into account, a capacity reli-ability assessment method was given as a function. Assessments were also performed regarding the effects of the conflicting pedestrian and bicycle volumes on capacity reliability. The simulation indicates that the pe-destrians and bicycles result in greater random fluctuations of exclusive tuming lane capacities, but have less effect on the variability of shared lane capacities. Normal distributions can be used to model the capaci-ties for intervals not less than 10 min. At higher vehicular volumes, the capacity reliability is more sensitive to the mean and standard deviation of the pedestrian and bicycle volumes.
Robert Rijavec
2013-02-01
Full Text Available There are different factors that affect driver’s behaviour at an urban signalized intersection. Complementary countdown signal heads can be used to inform the driver about the traffic light phase status. In the research presented in this paper, we explored how a countdown signal affects the driver’s reaction. We focused on the analysis of red/amber, red and amber running violations. We also observed and measured traffic flow start-up lost time and headway per cycle. Measurements took place in Ljubljana at a four-way intersection where two countdown signal heads are installed that face different directions. We used the “on-off-on” approach, using video surveillance and detection technology. According to the results of the investigative questionnaire, more than 84% of the surveyed drivers expressed positive opinion about the device. Analyses of field-test results have shown that the red and/or amber running violation rate is higher when the device is turned off. The results of the paper suggest that the countdown device had very little effect on the capacity of an urban signalized intersection.
Estimation of Saturation Flow Rates at Signalized Intersections
Chang-qiao Shao
2012-01-01
Full Text Available The saturation flow rate is a fundamental parameter to measure the intersection capacity and time the traffic signals. However, it is revealed that traditional methods which are mainly developed using the average value of observed queue discharge headways to estimate the saturation headway might lead to underestimate saturation flow rate. The goal of this paper is to study the stochastic nature of queue discharge headways and to develop a more accurate estimate method for saturation headway and saturation flow rate. Based on the surveyed data, the characteristics of queue discharge headways and the estimation method of saturated flow rate are studied. It is found that the average value of queue discharge headways is greater than the median value and that the skewness of the headways is positive. Normal distribution tests were conducted before and after a log transformation of the headways. The goodness-of-fit test showed that for some surveyed sites, the queue discharge headways can be fitted by the normal distribution and for other surveyed sites, the headways can be fitted by lognormal distribution. According to the queue discharge headway characteristics, the median value of queue discharge headways is suggested to estimate the saturation headway and a new method of estimation saturation flow rates is developed.
An extended car-following model at signalized intersections
Yu, Shaowei; Shi, Zhongke
2014-08-01
To simulate car-following behaviors better when the traffic light is red, three successive car-following data at a signalized intersection of Jinan in China were collected by using a new proposed data acquisition method and then analyzed to select input variables of the extended car-following model. An extended car-following model considering two leading cars' accelerations was proposed, calibrated and verified with field data obtained on the basis of the full velocity difference model and then a comparative model used for comparative research was also proposed and calibrated in the light of the GM model. The results indicate that the extended car-following model could fit measured data well, and that the fitting precision of the extended model is prior to the comparative model, whose mean absolute error is reduced by 22.83%. Finally a theoretical car-following model considering multiple leading cars' accelerations was put forward which has potential applicable to vehicle automation system and vehicle safety early warning system, and then the linear stability analysis and numerical simulations were conducted to analyze some observed physical features existing in the realistic traffic.
Effects of turning and through lane sharing on traffic performance at intersections
Li, Xiang; Sun, Jian-Qiao
2016-02-01
Turning vehicles strongly influence traffic flows at intersections. Effective regulation of turning vehicles is important to achieve better traffic performance. This paper studies the impact of lane sharing and turning signals on traffic performance at intersections by using cellular automata. Both right-turn and left-turn lane sharing are studied. Interactions between vehicles and pedestrians are considered. The transportation efficiency, road safety and energy economy are the traffic performance metrics. Extensive simulations are carried out to study the traffic performance indices. It is observed that shared turning lanes and permissive left-turn signal improve the transportation efficiency and reduce the fuel consumption in most cases, but the safety is usually sacrificed. It is not always beneficial for the through vehicles when they are allowed to be in the turning lanes.
Impact of Driver Behavior on Capacity at the Signalized Intersections%驾驶者行为选择对十字路口通行能力的影响
吴腾宇; 徐寅峰; 张珩
2015-01-01
考虑通过十字路口时左转车辆和直行车辆发生路权冲突时的不同驾驶者行为，将驾驶者分为跟随型驾驶者和谦让型驾驶者，并建立了左转车辆通过十字路口的模型，研究不同的驾驶者行为选择对十字路口通行能力的影响。结果表明，随着交通流量逐渐增加，驾驶者的行为越趋向于跟随时，十字路口的通行能力将会急剧降低；而当驾驶者的行为趋向于谦让时，十字路口的通行能力甚至优于有交警指挥的情形。该结果很好地解释了在行车高峰期中国十字路口堵塞的原因，即驾驶者的行为选择，可以通过改变驾驶者的行为选择和在交通流量达到一定的饱和度时派出交警来改善十字路口的通行能力。%When the conflicts between the left-turn vehicles and the through vehicles have happened at the signal-ized intersection, we consider different driver behaviors and divide the drivers into two types:the following driver and the humility driver, and build a model of the left-turn vehicles going through the intersection.The impact on the intersection’ s capacity by the different driver behavior is studied.The results show that when all the drivers are the following drivers, with the increase of the traffic flow, the capacity of the intersection decreases sharply. When all the drivers are the humility drivers, considering the situation that the policeman directs traffic, the capacity of the intersection will be better.These results can explain the reason for the blocking of the intersec-tions at the heavy traffic time in China well.We can improve the capacity of the intersections by changing the driver behavior and by directing traffic by a policeman.
Characteristics of traffic flow at a non-signalized intersection in the framework of game theory
Fan, Hongqiang; Jia, Bin; Tian, Junfang; Yun, Lifen
2014-12-01
At a non-signalized intersection, some vehicles violate the traffic rules to pass the intersection as soon as possible. These behaviors may cause many traffic conflicts even traffic accidents. In this paper, a simulation model is proposed to research the effects of these behaviors at a non-signalized intersection. Vehicle’s movement is simulated by the cellular automaton (CA) model. The game theory is introduced for simulating the intersection dynamics. Two types of driver participate the game process: cooperator (C) and defector (D). The cooperator obey the traffic rules, but the defector does not. A transition process may occur when the cooperator is waiting before the intersection. The critical value of waiting time follows the Weibull distribution. One transition regime is found in the phase diagram. The simulation results illustrate the applicability of the proposed model and reveal a number of interesting insights into the intersection management, including that the existence of defectors is benefit for the capacity of intersection, but also reduce the safety of intersection.
Xiaomeng Li
2012-01-01
Full Text Available The operational efficiency and safety of pedestrian flows at intersections is an important aspect of urban traffic. Particularly, conflicts between pedestrians and vehicles in crosswalk are one of the most influential factors for intersection safety. This paper presents a cellular automata model that simulates pedestrian and vehicle crossing behaviors at signalized intersections. Through the simulation, we investigate the effects of different pedestrian signal timing and crosswalk widths on the crosswalk capacity, the number of traffic conflicts between pedestrians and vehicles, and pedestrian delay due to the conflicts. The simulation results indicate that the cellular automata is an effective simulation platform for investigating complex pedestrian-related traffic phenomenon at signalized intersections.
Shahriar Afandizadeh Zargari
2015-12-01
Full Text Available The primary objective of this research is to optimize signal timing in consecutive signalized intersections. In this paper, the combination of genetic programming (GP with genetic algorithms (GA and neural network (NN with genetic algorithm (GA were used and compared in order to optimize signal timing in consecutive signalized intersections. First, genetic programming and neural network were constructed from existing signal timing data to predict the delay of intersections. Then genetic algorithm was applied to optimize these predictive networks (GP and NN. The results and comparisons of timing process and error percentage showed that neural network is more efficient than genetic programming. However, the ability of genetic programming in producing formula is a specific characteristic which makes it more applicable than neural network. Finally, for validating the results, Aimsun and Synchro micro simulation software were used, and accuracy of our models was approved.
THE DIFFERENCES OF DRIVING BEHAVIOR AMONG DIFFERENT DRIVER AGE GROUPS AT SIGNALIZED INTERSECTIONS
Jian John LU, Ph.D., P.E.
2000-01-01
Full Text Available Over the past few years the population of older drivers has substantially increased across the United States. Older drivers are a group of special interest because of their potential age-related deficiencies. It is essential to understand their driving behavior and adjust the conditions of roadway systems according to their requirements. Likewise, driving behavior of older drivers needs to be considered in order to adequately estimate capacities at intersections. In the past few years, research projects were performed by the University of South Florida to analyze the differences of driving behavior among different driver age groups. Typically, the driving behavior of older drivers was evaluated by analyzing their start-up lost time and saturation headway at signalized intersections as compared to young and mid-age driver groups. Research results were based on data collected from signalized intersections with different land-use types. These intersections are located in west and central Florida where the elderly population has been increasing rapidly in recent years. From the results it was found that the presence of older drivers significantly reduced intersection capacity at all study sites because of their higher lost times and lower saturation flow rates. Therefore, driving behavior of older drivers should be considered in designing intersections located in places with a significant older driver population. In the research, models were developed to predict start-up lost time and saturation headway values generated by older drivers. Then, the variation in capacities with an increasing percentage of older drivers in the traffic stream was modeled. Finally, adjustment factors for different percentages of older drivers were developed to adjust intersection capacity. These factors are believed to account for the presence of older drivers in the traffic stream. The adjustment factors may be used in capacity analysis and design procedures for
Empirical Analysis and Modeling of Stop-Line Crossing Time and Speed at Signalized Intersections
Tang, Keshuang; Wang, Fen; Yao, Jiarong; Sun, Jian
2016-01-01
In China, a flashing green (FG) indication of 3 s followed by a yellow (Y) indication of 3 s is commonly applied to end the green phase at signalized intersections. Stop-line crossing behavior of drivers during such a phase transition period significantly influences safety performance of signalized intersections. The objective of this study is thus to empirically analyze and model drivers’ stop-line crossing time and speed in response to the specific phase transition period of FG and Y. High-resolution trajectories for 1465 vehicles were collected at three rural high-speed intersections with a speed limit of 80 km/h and two urban intersections with a speed limit of 50 km/h in Shanghai. With the vehicle trajectory data, statistical analyses were performed to look into the general characteristics of stop-line crossing time and speed at the two types of intersections. A multinomial logit model and a multiple linear regression model were then developed to predict the stop-line crossing patterns and speeds respectively. It was found that the percentage of stop-line crossings during the Y interval is remarkably higher and the stop-line crossing time is approximately 0.7 s longer at the urban intersections, as compared with the rural intersections. In addition, approaching speed and distance to the stop-line at the onset of FG as well as area type significantly affect the percentages of stop-line crossings during the FG and Y intervals. Vehicle type and stop-line crossing pattern were found to significantly influence the stop-line crossing speed, in addition to the above factors. The red-light-running seems to occur more frequently at the large intersections with a long cycle length.
Quality of pedestrian flow and crosswalk width at signalized intersections
Wael K.M. Alhajyaseen
2010-07-01
Full Text Available Among various pedestrian facilities, signalized crosswalks are the most complex and critical ones. Their geometry and configuration including width, position and angle directly affect the safety, cycle length and resulting delays for all users. Existing manuals do not provide clear and rational specifications for the required crosswalk width under different pedestrian demand combinations and properties. Furthermore, they do not consider the bi-directional flow effects on crossing speed and time when addressing pedestrian flow at signalized crosswalks. However, quantifying the effects of such interactions on the behavior of pedestrian flow is a prerequisite for improving the geometric design and configuration of signalized crosswalks. The objective of this paper is to develop a methodology for estimating the required crosswalk width at different pedestrian demand combinations and a pre-defined LOS. The developed methodology is based on theoretical modeling for total pedestrian platoon crossing time, which consists of discharge and crossing times. The developed models are utilized to generate the fundamental diagrams of pedestrian flow at signalized crosswalks. A comprehensive discussion about the effects of bi-directional flow and various pedestrian age groups on the characteristics of pedestrian flow and the capacity of signalized crosswalks is presented. It is found that the maximum reduction in the capacity of signalized crosswalks occurs at roughly equal pedestrian flows from both sides of the crosswalk. By utilizing existing LOS thresholds for pedestrian flow at signalized crosswalks, the required crosswalk widths for various pedestrian demand combinations are proposed for implementation.
Gallagher, Brian R.; de Oca, Patricia Montes
1998-01-01
Presents guidelines for orientation and mobility instructors and traffic engineers to assess the need for adaptive devices to make crosswalks at signalized intersections accessible to pedestrians with visual impairments. The discussions of audible and tactile pedestrian devices, along with case examples, distinguish when each device should be…
Comparative analysis of risky behaviors of electric bicycles at signalized intersections.
Bai, Lu; Liu, Pan; Guo, Yanyong; Yu, Hao
2015-01-01
The primary objective of this study was to compare the risky behaviors of e-bike, e-scooter, and bicycle riders as they were crossing signalized intersections. Pearson's chi-square test was used to identify whether there were significant differences in the risky behaviors among e-bike, e-scooter, and bicycle riders. Binary logit models were developed to evaluate how various variables affected the behaviors of 2-wheeled vehicle riders at signalized intersections. Field data collection was conducted at 13 signalized intersections in 2 cities (Nanjing and Kunming) in China. Three different types of risky behaviors were identified, including stop beyond the stop line, riding in motorized lanes, and riding against traffic. Two-wheeled vehicle riders' gender and age and traffic conditions were significantly associated with the behaviors of 2-wheeled vehicle riders at the selected signalized intersections. Compared to e-bike and bicycle riders, e-scooter riders are more likely to take risky behaviors. More specifically, they are more likely to ride in motorized lanes and ride against traffic.
Strauss, Jillian; Miranda-Moreno, Luis F; Morency, Patrick
2013-10-01
This study proposes a two-equation Bayesian modelling approach to simultaneously study cyclist injury occurrence and bicycle activity at signalized intersections as joint outcomes. This approach deals with the potential presence of endogeneity and unobserved heterogeneities and is used to identify factors associated with both cyclist injuries and volumes. Its application to identify high-risk corridors is also illustrated. Montreal, Quebec, Canada is the application environment, using an extensive inventory of a large sample of signalized intersections containing disaggregate motor-vehicle traffic volumes and bicycle flows, geometric design, traffic control and built environment characteristics in the vicinity of the intersections. Cyclist injury data for the period of 2003-2008 is used in this study. Also, manual bicycle counts were standardized using temporal and weather adjustment factors to obtain average annual daily volumes. Results confirm and quantify the effects of both bicycle and motor-vehicle flows on cyclist injury occurrence. Accordingly, more cyclists at an intersection translate into more cyclist injuries but lower injury rates due to the non-linear association between bicycle volume and injury occurrence. Furthermore, the results emphasize the importance of turning motor-vehicle movements. The presence of bus stops and total crosswalk length increase cyclist injury occurrence whereas the presence of a raised median has the opposite effect. Bicycle activity through intersections was found to increase as employment, number of metro stations, land use mix, area of commercial land use type, length of bicycle facilities and the presence of schools within 50-800 m of the intersection increase. Intersections with three approaches are expected to have fewer cyclists than those with four. Using Bayesian analysis, expected injury frequency and injury rates were estimated for each intersection and used to rank corridors. Corridors with high bicycle volumes
Estimating intersection turning volumes from actuated traffic signal information
Ali Gholami
2016-12-01
Full Text Available Actuated traffic signals usually use loop detectors. The current practice in many cities is to install four consecutive loop detectors in each lane to reduce the chance of undetected vehicles. Due to practical reasons, all four loop detectors in each lane and other detectors referring to the same phase are spliced together. Thus, it is possible for several vehicles to be counted as one single car. This way of detector wiring to the cabinet reduces the accuracy of detectors for collecting traffic volumes. Our preliminary studies show cases with an error greater than 75 percent. Therefore, the purpose of this paper is to provide a simple method to obtain turning volumes from signal information in actuated non-coordinated traffic signals without using loop detector data. To produce the required data, a simulation was performed in VISSIM with different input volumes. To change turning volumes, a code was developed in COM interface. With this code, the inputs did not have to be changed manually. In addition, the COM code stored the outputs. Data were then exported to a single Excel file. Afterwards, regression and the adaptive neural fuzzy inference system (ANFIS were used to build models to obtain turning volumes. The accuracy of models is defined in terms of mean absolute percent error (MAPE. Results of our two case studies show that during peak hours, there is a high correlation between actuated green time and volumes. This method does not need extensive data collection and is easy to be employed. The results also show that ANFIS produces more accurate models compared to regression.
Childrens' left-turning preference is not modulated by magical ideation.
Streuli, Jürg C; Obrist, Gina; Brugger, Peter
2017-01-01
The literature on human turning preferences is inconsistent. While the few studies with children below 14 years of age uniformly describe an overall left-turning (counterclockwise) tendency, a recent Internet study with more than 1500 adults found a right-sided (clockwise) bias. We set out to investigate spontaneous turning behaviour in children age 5-3 years and, based on neuropsychiatric work in adults, also explored a potential association with magical thinking. Findings indicated a clear left-turning preference, independent of a participant's sex and handedness. Whether a child responded a question about the existence of extrasensory communication in the affirmative or not was unrelated to direction and size of turning bias and lateral preference. Our results are consistent with a left-sided turning preference reported for children, but in opposition to the clockwise bias recently described in a large-scale study with adults. Whether they point to a maturational gradient in the preferred direction of spontaneous whole-body rotation or rather to a lack of comparability between measures used in observational versus Internet-based studies remains to be further investigated. Regarding a purported association between body turns and magical thinking, our study is preliminary, as only one single question was used to probe the latter.
IMPACTS OF GROUP-BASED SIGNAL CONTROL POLICY ON DRIVER BEHAVIOR AND INTERSECTION SAFETY
Keshuang TANG
2008-01-01
Full Text Available Unlike the typical stage-based policy commonly applied in Japan, the group-based control (often called movement-based in the traffic control industry in Japan refers to such a control pattern that the controller is capable of separately allocating time to each signal group instead of stage based on traffic demand. In order to investigate its applicability at signalized intersections in Japan, an intersection located in Yokkaichi City of Mie Prefecture was selected as an experimental application site by the Japan Universal Traffic Management Society (UTMS. Based on the data collected at the intersection before and after implementing the group-based control policy respectively, this study evaluated the impacts of such a policy on driver behavior and intersection safety. To specify those impacts, a few models utilizing cycle-based data were first developed to interpret the occurrence probability and rate of red-light-running (RLR. Furthermore, analyses were performed on the yellow-entry time (Ye of the last cleared vehicle and post encroachment time (PET during the phase switching. Conclusions supported that the group-based control policy, along with certain other factors, directly or indirectly influenced the RLR behavior of through and right-turn traffics. Meanwhile, it has potential safety benefits as well, indicated by the declined Ye and increased PET values.
Waiting Endurance Time Estimation of Electric Two-Wheelers at Signalized Intersections
Mei Huan
2014-01-01
Full Text Available The paper proposed a model for estimating waiting endurance times of electric two-wheelers at signalized intersections using survival analysis method. Waiting duration times were collected by video cameras and they were assigned as censored and uncensored data to distinguish between normal crossing and red-light running behavior. A Cox proportional hazard model was introduced, and variables revealing personal characteristics and traffic conditions were defined as covariates to describe the effects of internal and external factors. Empirical results show that riders do not want to wait too long to cross intersections. As signal waiting time increases, electric two-wheelers get impatient and violate the traffic signal. There are 12.8% of electric two-wheelers with negligible wait time. 25.0% of electric two-wheelers are generally nonrisk takers who can obey the traffic rules after waiting for 100 seconds. Half of electric two-wheelers cannot endure 49.0 seconds or longer at red-light phase. Red phase time, motor vehicle volume, and conformity behavior have important effects on riders’ waiting times. Waiting endurance times would decrease with the longer red-phase time, the lower traffic volume, or the bigger number of other riders who run against the red light. The proposed model may be applicable in the design, management and control of signalized intersections in other developing cities.
Delay-based Passenger Car Equivalent at Signalized Intersections in Iran
Habibollah Nassiri
2017-04-01
Full Text Available Due to their different sizes and operational characteristics, vehicles other than passenger cars have a different influence on traffic operations especially at intersections. The passenger car equivalent (PCE is the parameter that shows how many passenger cars must be substituted for a specific heavy vehicle to represent its influence on traffic operation. PCE is commonly estimated using headway-based methods that consider the excess headway utilized by heavy vehicles. In this research, the PCE was estimated based on the delay parameter at three signalized intersections in Tehran, Iran. The data collected were traffic volume, travel time for each movement, signalization, and geometric design information. These data were analysed and three different models, one for each intersection, were constructed and calibrated using TRAF-NETSIM simulation software for unsaturated traffic conditions. PCE was estimated under different scenarios and the number of approach movements at each intersection. The results showed that for approaches with only one movement, PCE varies from 1.1 to 1.65. Similarly, for approaches with two and three movements, the PCE varies from 1.07 to 1.99 and from 0.76 to 3.6, respectively. In addition, a general model was developed for predicting PCE for intersections with all of the movements considered. The results obtained from this model showed that the average PCE of 1.5 is similar to the value recommended by the HCM (Highway Capacity Manual 1985. However, the predicted PCE value of 1.9 for saturated threshold is closer to the PCE value of 2 which was recommended by the HCM 2000 and HCM 2010.
Cycle-by-Cycle Queue Length Estimation for Signalized Intersections Using Multi-Source Data
Zhongyu Wang; Qing Cai; Bing Wu; Yinhai Wang; Linbo Li
2015-01-01
In order to estimate vehicular queue length at signalized intersections accurately and overcome the shortcomings and restrictions of existing studies especially those based on shockwave theory, a new methodology is presented for estimating vehicular queue length using data from both point detectors and probe vehicles. The methodology applies the shockwave theory to model queue evolution over time and space. Using probe vehicle locations and times as well as point detector measured traffic states, analytical formulations for calculating the maximum and minimum ( residual) queue length are developed. The proposed methodology is verified using ground truth data collected from numerical experiments conducted in Shanghai, China. It is found that the methodology has a mean absolute percentage error of 17�09%, which is reasonably effective in estimating the queue length at traffic signalized intersections. Limitations of the proposed models and algorithms are also discussed in the paper.
Vehicle Delay Estimation for an Isolated Intersection under Actuated Signal Control
Shumin Feng
2014-01-01
Full Text Available Vehicle delay at an actuated signal control (ASC intersection is analyzed and computed with the aim of reflecting the effects of ASC and optimizing its parameters. The operation characteristics of traffic flows at the intersections serve as the foundation to present the mechanism of vehicle delay under the ASC; given that the arrival of vehicles obeys the Poisson distribution, probability algorithms of vehicle delay are put forward under the semi-ASC and fully ASC depending on discretization of green time. Computation process is illustrated by case study and CORSIM simulation experiments. Finally, the primary results indicate that the appropriate control modes can decrease vehicle delay, which is significantly affected by unit extension. Hopefully, the study will provide useful information for selecting different ASC modes and optimizing signal control parameters.
Intersection of AHR and Wnt Signaling in Development, Health, and Disease
Andrew J. Schneider
2014-10-01
Full Text Available The AHR (aryl hydrocarbon receptor and Wnt (wingless-related MMTV integration site signaling pathways have been conserved throughout evolution. Appropriately regulated signaling through each pathway is necessary for normal development and health, while dysregulation can lead to developmental defects and disease. Though both pathways have been vigorously studied, there is relatively little research exploring the possibility of crosstalk between these pathways. In this review, we provide a brief background on (1 the roles of both AHR and Wnt signaling in development and disease, and (2 the molecular mechanisms that characterize activation of each pathway. We also discuss the need for careful and complete experimental evaluation of each pathway and describe existing research that explores the intersection of AHR and Wnt signaling. Lastly, to illustrate in detail the intersection of AHR and Wnt signaling, we summarize our recent findings which show that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD-induced disruption of Wnt signaling impairs fetal prostate development.
Xun Li
2017-01-01
Full Text Available We proposed a signal control optimization model for urban main trunk line intersections. Four-phase intersection was analyzed and modeled based on the Cell Transmission Model (CTM. CTM and signal control model in our study had both been improved for multi-intersections by three-phase theory and information-exchanging. To achieve a real-time application, an improved genetic algorithm (GA was proposed finally, the DISCO traffic simulation software was used for numerical simulation experiment, and comparisons with the standard GA and CTM were reported in this paper. Experimental results indicate that our searching time is less than that of SGA by 38%, and our method needs only 1/3 iteration time of SGA. According to our DISCO traffic simulation processing, compared with SGA, if the input traffic flow is changed from free phase to synchronized phase, for example, less than 900 vel/h, the delay time can reduce to 87.99% by our method, and the minimum delay time is 77.76% of existing method. Furthermore, if input traffic volume is increased to 1200 vel/h or more at the synchronized phase, the summary and minimum values of average delay time are reduced to 81.16% and 75.83%, respectively, and the average delay time is reduced to 17.72 seconds.
Changjiang Zheng
2012-01-01
Full Text Available To solve the problem in pedestrian Mid-Block street crossing, the method of signal coordination control between mid-block street crossing and intersection is researched in this paper. The paper proposes to use “distance-flow rate-time” graph as the tool for building coordination control system model which is for different situations of traffic control. Through alternating the linear optimization model, the system outputs the distribution of signal timing and system operational factors (delays in vehicles and mid-block street crossing. Finally, taking one section on the Taiping North Road in Nanjing as an example, the signal coordination control is carried out. And the results which are delays in the vehicles and mid-block street crossing are compared to those in the current distribution of signal timing.
Effects of flashing green on driver’s stop/go decision at signalized intersection
沈家军; 王炜
2015-01-01
The primary objective of this work is to explore how drivers react to flashing green at signalized intersections. Through video taping and data procession based on photogrammetry, the operating speeds of vehicles before and after the moment when flashing green started was compared using paired-samples T-test. The critical distances between go and stop decisions was defined through cumulative percentage curve. The boundary of dilemma zone was determined by comparing stop distance and travel distance. Amber-running violation was analyzed on the basis of the travel time to the stop line. And finally, a logistic model for stop and go decisions was constructed. The results shows that the stopping ratios of the first vehicles of west-bound and east-bound approaches are 41.3% and 39.8%, respectively; the amber-light running violation ratios of two approaches are 31.6% and 25.4%, respectively; the operating speed growth ratios of first vehicles selecting to cross intersection after the moment when flashing green started are 26.7% and 17.7%, respectively; and the critical distances are 48 m and 46 m, respectively, which are close to 44 m, the boundary of dilemma zone. The developed decision models demonstrate that the probability of go decision is higher when the distance from the stop line is shorter or operating speed is higher. This indicates that flashing green is an effective way to enhance intersection safety, but it should work together with a strict enforcement. In addition, traffic signs near critical distance and reasonable speed limitation are also beneficial to the safety of intersections.
Solving a signalized traffic intersection problem with an hyperbolic penalty function
Melo, Teófilo; Monteiro, M. Teresa T.; Matias, João
2012-09-01
Mathematical Program with Complementarity Constraints (MPCC) finds many applications in fields such as engineering design, economic equilibrium and mathematical programming theory itself. A queueing system model resulting from a single signalized intersection regulated by pre-timed control in traffic network is considered. The model is formulated as an MPCC problem. A MATLAB implementation based on an hyperbolic penalty function is used to solve this practical problem, computing the total average waiting time of the vehicles in all queues and the green split allocation. The problem was codified in AMPL.
Yi Zhao
2017-01-01
Full Text Available The aim of this paper is to study the headway distribution of queued vehicles (less than 16 vehicles at signalized intersections. Existing studies usually take the average statistics of headway at any queuing place. When different percentile points of statistical data are assigned to headway, the passing rate (the rate of all queued vehicles passing the stop line under the ideal signal timing scheme varies. When selecting the mean value, the passing rate of a queue of fewer than 16 vehicles is no more than 65%. When selecting 75% as the percentile, the passing rate is up to 94%. The queue length also decides the assigned percentile of headway to ensure the passing rate reaches a certain level. The value assignation of headway directly affects lane capacity and start-up loss time. This paper provides a new perspective on parameter calibration and will make the signal timing algorithm method more effective.
Arasaki, Yasuki; Takatsuka, Kazuo
2017-08-01
A computational scheme of energy- and geometry-dependent photoelectron signals from the dynamics near a conical intersection based on a simplified path-branching representation of nonadiabatic electron wavepacket dynamics is proposed. Taking the NO2 X / A conical intersection as an example, the results of the present scheme compared to those from previous study based on the method of full quantum vibrational wavepacket shows qualitative agreement suggesting promising application to computation in larger systems intractable to full quantum exact methods.
A Model for Capacity Considering the Interference by Pedestrian Traffic at Signal Intersections
Yixin Chen; Yulong He; Xiaoduan Sun
2016-01-01
The capacity is impacted badly by pedestrians’ violation behavior at signal intersections. In order to quantify the impact, the time⁃headway and the vehicular speed from start⁃up to reach the stable saturation flow with and without pedestrian traffic are used as the direct measurements. Using the statistical analysis, the time⁃headway of saturation flow is mainly affected by the position of pedestrians and the degree of pedestrians ’ influence is classified into four levels. Then the speed⁃time profile for the vehicular acceleration at each level is fitted by Curve Fitting Software. Based on the effect to the time⁃headway and acceleration time, the model of capacity influenced by pedestrians is established and the influence is quantified, which enriches the fundamental theory of traffic engineering. The result shows that the vehicular capacity can be decreased by 14%at the worst case ( level I ) . The conclusions obtained in this paper are valuable for better management of the signal intersection.
李岩; 陈宽民; 过秀成
2013-01-01
In order to analyze the impact of stretching-segment on the saturated flow rate of signalized intersection approach, an improved cellular automation model was proposed to estimate its saturated flow rate. The NaSch model was improved by adding different slow probabilities, turning deceleration rules and modified lane changing rules. The relationship between the saturated flow rate of stretching-segments and adjacent lanes was tested in numerical simulation. The length of stretching-segment, cycle length and green time were selected as impact factors of the cellular automation model. The simulation result indicates that the geometrics design of stretching-segment and the traffic signal timing scenario have major effects on the saturated flow rate of the intersection approach. The saturated flow rate will continually increase with increasing stretching-segment length until it reaches a threshold. After reaching the threshold, the stretching-segment can be treated as a separate lane. The green time is approximately linearly related to the threshold length of the stretching-segment. An optimum cycle length exists when the length of the stretching-segment is not long enough, and it is approximately linearly related to the length of stretching-segment.
A Study of Dynamic Right-Turn Signal Control Strategy at Mixed Traffic Flow Intersections
Zhizhou Wu
2014-12-01
Full Text Available Traffic conflicts among right-turn vehicles (RTVs, non-motorized vehicles (NMVs and pedestrians were examined for urban signalized intersections with exclusive right-turn lane. This study proposed an approach to dynamically calculate the duration of the prohibited right-turn for vehicles by using a measure called the Degree of Clustered Conflict (DCC. The process of DCC control includes: 1 quantitative calculation of DCC value in the conflict area; 2 establishing the general cost model that combines the delay and conflict indicators; and 3 applying the DCC-control time model to control RTV in real time. Based on these, the paper presented a general approach of detailed dynamic on-line signal control process of RTV. Finally, the RTV control process was programmed based on VISSIM simulation to evaluate the control effectiveness. The results showed that the general cost (weighted summation of delay and conflict of the RTV control decreases rapidly compared with non-control, fixed control and full control (drop of 58%, 35% and 42% under small flow conditions and 70%, 59% and 17% in the large flow conditions, respectively. The method not only improved the operation efficiency, but also reduced the potential safety risks among traffic participants when vehicles turn right at intersections.
Kime, Cody; Sakaki-Yumoto, Masayo; Goodrich, Leeanne; Hayashi, Yohei; Sami, Salma; Derynck, Rik; Asahi, Michio; Panning, Barbara; Yamanaka, Shinya; Tomoda, Kiichiro
2016-01-01
Developmental signaling molecules are used for cell fate determination, and understanding how their combinatorial effects produce the variety of cell types in multicellular organisms is a key problem in biology. Here, we demonstrate that the combination of leukemia inhibitory factor (LIF), bone morphogenetic protein 4 (BMP4), lysophosphatidic acid (LPA), and ascorbic acid (AA) efficiently converts mouse primed pluripotent stem cells (PSCs) into naive PSCs. Signaling by the lipid LPA through its receptor LPAR1 and downstream effector Rho-associated protein kinase (ROCK) cooperated with LIF signaling to promote this conversion. BMP4, which also stimulates conversion to naive pluripotency, bypassed the need for exogenous LPA by increasing the activity of the extracellular LPA-producing enzyme autotaxin (ATX). We found that LIF and LPA-LPAR1 signaling affect the abundance of signal transducer and activator of transcription 3 (STAT3), which induces a previously unappreciated Kruppel-like factor (KLF)2-KLF4-PR domain 14 (PRDM14) transcription factor circuit key to establish naive pluripotency. AA also affects this transcription factor circuit by controlling PRDM14 expression. Thus, our study reveals that ATX-mediated autocrine lipid signaling promotes naive pluripotency by intersecting with LIF and BMP4 signaling. PMID:27738243
A PREDICTIVE STUDY: CARBON MONOXIDE EMISSION MODELING AT A SIGNALIZED INTERSECTION
FREDDY WEE LIANG KHO
2014-02-01
Full Text Available CAL3QHC dispersion model was used to predict the present and future carbonmonoxide (CO levels at a busy signalized intersection. This study attempted to identify CO “hot-spots” at nearby areas of the intersection during typical A.M. and P.M. peak hours. The CO concentration “hot-spots” had been identified at 101 Commercial Park and the simulated maximum 1-hour Time-Weighted Average (1-h TWA ground level CO concentrations of 18.3 ppm and 18.6 ppm had been observed during A.M. and P.M. peaks, respectively in year 2006. This study shows that there would be no significant increment in CO level for year 2014 although a substantial increase in the number of vehicles is assumed to affect CO levels. It was also found that CO levels would be well below the Malaysian Ambient Air Quality Guideline of 30 ppm (1-h TWA. Comparisons between the measured and simulated CO levels using quantitative data analysis technique and statistical methods indicated that CAL3QHC dispersion model correlated well with measured data.
Ghanipoor Machiani, Sahar; Abbas, Montasir
2016-11-01
Drivers' indecisiveness in dilemma zones (DZ) could result in crash-prone situations at signalized intersections. DZ is to the area ahead of an intersection in which drivers encounter a dilemma regarding whether to stop or proceed through the intersection when the signal turns yellow. An improper decision to stop by the leading driver, combined with the following driver deciding to go, can result in a rear-end collision, unless the following driver recognizes a collision is imminent and adjusts his or her behavior at or shortly after the onset of yellow. Considering the significance of DZ-related crashes, a comprehensive safety measure is needed to characterize the level of safety at signalized intersections. In this study, a novel safety surrogate measure was developed utilizing real-time radar field data. This new measure, called safety surrogate histogram (SSH), captures the degree and frequency of DZ-related conflicts at each intersection approach. SSH includes detailed information regarding the possibility of crashes, because it is calculated based on the vehicles conflicts. An example illustrating the application of the new methodology at two study sites in Virginia is presented and discussed, and a comparison is provided between SSH and other DZ-related safety surrogate measures mentioned in the literature. The results of the study reveal the efficacy of the SSH as complementary to existing surrogate measures.
Kowalewski, Markus, E-mail: mkowalew@uci.edu; Mukamel, Shaul, E-mail: smukamel@uci.edu [Department of Chemistry, University of California, Irvine, California 92697-2025 (United States)
2015-07-28
Femtosecond Stimulated Raman Spectroscopy (FSRS) signals that monitor the excited state conical intersections dynamics of acrolein are simulated. An effective time dependent Hamiltonian for two C—H vibrational marker bands is constructed on the fly using a local mode expansion combined with a semi-classical surface hopping simulation protocol. The signals are obtained by a direct forward and backward propagation of the vibrational wave function on a numerical grid. Earlier work is extended to fully incorporate the anharmonicities and intermode couplings.
Ren, Yilong; Wang, Yunpeng; Wu, Xinkai; Yu, Guizhen; Ding, Chuan
2016-10-01
Red light running (RLR) has become a major safety concern at signalized intersection. To prevent RLR related crashes, it is critical to identify the factors that significantly impact the drivers' behaviors of RLR, and to predict potential RLR in real time. In this research, 9-month's RLR events extracted from high-resolution traffic data collected by loop detectors from three signalized intersections were applied to identify the factors that significantly affect RLR behaviors. The data analysis indicated that occupancy time, time gap, used yellow time, time left to yellow start, whether the preceding vehicle runs through the intersection during yellow, and whether there is a vehicle passing through the intersection on the adjacent lane were significantly factors for RLR behaviors. Furthermore, due to the rare events nature of RLR, a modified rare events logistic regression model was developed for RLR prediction. The rare events logistic regression method has been applied in many fields for rare events studies and shows impressive performance, but so far none of previous research has applied this method to study RLR. The results showed that the rare events logistic regression model performed significantly better than the standard logistic regression model. More importantly, the proposed RLR prediction method is purely based on loop detector data collected from a single advance loop detector located 400 feet away from stop-bar. This brings great potential for future field applications of the proposed method since loops have been widely implemented in many intersections and can collect data in real time. This research is expected to contribute to the improvement of intersection safety significantly.
Partha SAHA
2009-01-01
PCE currently used in Bangladesh is based on the values given in Geometric Design of Highways (MoC, 2001, which is the modification of the values given by Webster (1958 on the study performed in the United Kingdom in the 50's and 60's. But now-a-days, the situation is far different both for traffic and road user as the characteristics have changed from that time. Hence, in this paper an empirical study was carried out to determine the PCE of different types of vehicle that reflect the actual traffic conditions of Dhaka Metropolitan City. Data were collected from ten signalized intersections and the headway ratio method was used to estimate the PCE of different types of vehicle. The main vehicle compositions observed during the study period consist of passenger cars, auto-rickshaws, mini-buses and buses. The PCE obtained in this study were compared to the values established earlier. It was found that the estimated PCE are smaller than those being used in Bangladesh.
Warner, Jennifer; Hurwitz, David S; Monsere, Christopher M; Fleskes, Kayla
2017-07-01
A right-hook crash is a crash between a right-turning motor vehicle and an adjacent through-moving bicycle. At signalized intersections, these crashes can occur during any portion of the green interval when conflicting bicycles and vehicles are moving concurrently. The objective of this research was to evaluate the effectiveness of four types of engineering countermeasures - regulatory signage, intersection pavement marking, smaller curb radius, and protected intersection design - at modifying driver behaviors that are known contributing factors in these crashes. This research focused on right-hook crashes that occur during the latter stage of the circular green indication at signalized intersections with a shared right-turn and through lane. Changes in driver performance in response to treatments were measured in a high-fidelity driving simulator. Twenty-eight participants each completed 22 right-turn maneuvers. A partially counterbalanced experimental design exposed drivers to critical scenarios, which had been determined in a previous experiment. For each turn, driver performance measures, including visual attention, crash avoidance, and potential crash severity, were collected. A total of 75 incidents (47 near-collisions and 28 collisions) were observed during the 616 right turns. All treatments had some positive effect on measured driver performance with respect to the right-turn vehicle conflicts. Further work is required to map the magnitude of these changes in driver performance to crash-based outcomes. Copyright © 2017 Elsevier Ltd. All rights reserved.
Wood, Jonathan; Donnell, Eric T
2016-08-01
The continuous green T intersection is characterized by a channelized left-turn movement from the minor street approach onto the major street, along with a continuous through movement on the major street. The continuous flow through movement is not controlled by the three-phase traffic signal that is used to separate all other movements at the intersection. Rather, the continuous through movement typically has a green through arrow indicator to inform drivers that they do not have to stop. Past research has consistently shown that there are operational and environmental benefits to implementing this intersection form at three-leg locations, when compared to a conventional signalized intersection. These benefits include reduced delay, fuel consumption, and emissions. The safety effects of the conventional green T intersection are less clear. Past research has been limited to small sample sizes, or utilized only statistical comparisons reported crashes to evaluate the safety performance relative to similar intersection types. The present study overcomes past safety research evaluations by using a propensity scores-potential outcomes framework, with genetic matching, to compare the safety performance of the continuous green T to conventional signalized intersections, using treatment and comparison site data from Florida and South Carolina. The results show that the expected total, fatal and injury, and target crash (rear-end, angle, and sideswipe) frequencies are lower at the continuous green T intersection relative to the conventional signalized intersection (CMFs of 0.958 [95% CI=0.772-1.189], 0.846 [95% CI=0.651-1.099], and 0.920 [95% CI=0.714-1.185], respectively).
Prungchan Wongwises
2005-11-01
Full Text Available Based on the US EPA air pollution model, CAL3QHC version 2.0 was applied to predict carbon monoxide (CO concentrations from road traffic at three signalized intersections in Khon Kaen province. Four data groups required by the model, namely site parameters, traffic parameters, meteorological parameters and emission parameters were collected at each intersection and have been used as the inputs to the model. The prediction results were compared to the measurement. The results showed that the predicted CO concentration variations corresponding mostly to the measurement except at some hours when there was not good agreement due to an extreme upwind location of receptor, low wind speed, raining period, other out-sources of CO concentration such as another near intersection and parking lot. However, this study shows that the CAL3QHC model can be applied to predict CO concentration in the environmental condition of Thailand quite well. Moreover, the model might be used as a tool for assessing traffic air pollution at roadway intersection as well as for air quality management.
梁国华; 邓亚娟; 韩海; 马荣国; 卢杨
2015-01-01
intersection was constructed through overlapping the previous two rules. Taking the main signal intersection in the bidirectional six lanes as an example, the applicability of exclusive pedestrian signal phase and overpassing facilities were analyzed. The result indicates that the overpassing facilities are supposed to be adopted when the traffic less than 90 s, the proportion of left turn green split time is no less than 50% and the pedestrian volume is no less than 2 700 Ped·(h·m)-1.
Proposition of delay model for signalized intersections with queueing theory analytical models usage
Grzegorz SIERPIŃSKI
2007-01-01
Full Text Available Time delay on intersections is a very important transport problem. Thearticle includes a proposition of time delay model. Variance of service times is considered by used average waiting time in queue for queuing system with compressed queuing processes usage as a part of proposed time delays model.
Yang, Xiaobao; Huan, Mei; Abdel-Aty, Mohamed; Peng, Yichuan; Gao, Ziyou
2015-01-01
This paper presents a hazard-based duration approach to investigate riders' waiting times, violation hazards, associated risk factors, and their differences between cyclists and electric bike riders at signalized intersections. A total of 2322 two-wheeled riders approaching the intersections during red light periods were observed in Beijing, China. The data were classified into censored and uncensored data to distinguish between safe crossing and red-light running behavior. The results indicated that the red-light crossing behavior of most riders was dependent on waiting time. They were inclined to terminate waiting behavior and run against the traffic light with the increase of waiting duration. Over half of the observed riders cannot endure 49s or longer. 25% of the riders can endure 97s or longer. Rider type, gender, waiting position, conformity tendency and crossing traffic volume were identified to have significant effects on riders' waiting times and violation hazards. Electric bike riders were found to be more sensitive to the external risk factors such as other riders' crossing behavior and crossing traffic volume than cyclists. Moreover, unobserved heterogeneity was examined in the proposed models. The finding of this paper can explain when and why cyclists and electric bike riders run against the red light at intersections. The results of this paper are useful for traffic design and management agencies to implement strategies to enhance the safety of riders.
Delay Estimates of Mixed Traffic Flow at Signalized Intersections in China
SU Yuelong; WEI Zheng; CHENG Sihan; YAO Danya; ZHANG Yi; LI Li
2009-01-01
Two characteristics of Chinese mixed traffic invalidate the conventional queuing delay estimates for western countries. First, the driving characteristics of Chinese drivers lead to different delays even though the other conditions are the same. Second, urban traffic flow in China is often hindered by pedestrians at intersections, such that imported intelligent traffic control systems do not work appropriately. Typical delay estimates for Chinese conditions were obtained from data for over 500 vehicle queues in Beijing collected using charge coupled device (CCD) cameras. The results show that the delays mainly depend on the pro-portion and positions of heavy vehicles in the queue, as well as the start-up situations (with or without inter-ference). A simplified delay estimation model considers vehicle types and positions that compares well with the observed traffic delays.
Evaluation of Deployment Challenges of Wireless Sensor Networks at Signalized Intersections
Leyre Azpilicueta
2016-07-01
Full Text Available With the growing demand of Intelligent Transportation Systems (ITS for safer and more efficient transportation, research on and development of such vehicular communication systems have increased considerably in the last years. The use of wireless networks in vehicular environments has grown exponentially. However, it is highly important to analyze radio propagation prior to the deployment of a wireless sensor network in such complex scenarios. In this work, the radio wave characterization for ISM 2.4 GHz and 5 GHz Wireless Sensor Networks (WSNs deployed taking advantage of the existence of traffic light infrastructure has been assessed. By means of an in-house developed 3D ray launching algorithm, the impact of topology as well as urban morphology of the environment has been analyzed, emulating the realistic operation in the framework of the scenario. The complexity of the scenario, which is an intersection city area with traffic lights, vehicles, people, buildings, vegetation and urban environment, makes necessary the channel characterization with accurate models before the deployment of wireless networks. A measurement campaign has been conducted emulating the interaction of the system, in the vicinity of pedestrians as well as nearby vehicles. A real time interactive application has been developed and tested in order to visualize and monitor traffic as well as pedestrian user location and behavior. Results show that the use of deterministic tools in WSN deployment can aid in providing optimal layouts in terms of coverage, capacity and energy efficiency of the network.
Game Theory Model of Traffic Participants within Amber Time at Signalized Intersection
Weiwei Qi
2014-01-01
Full Text Available The traffic light scheme is composed of red, green, and amber lights, and it has been defined clearly for the traffic access of red and green lights; however, the definition of that for the amber light is indistinct, which leads to the appearance of uncertainty factors and serious traffic conflicts during the amber light. At present, the traffic administrations are faced with the decision of whether to forbid passing or not during the amber light in the cities of China. On one hand, it will go against the purpose of setting amber lights if forbidding passing; on the other hand, it may lead to a mess of traffic flow running if not. And meanwhile the drivers are faced with the decision of passing the intersection or stopping during the amber light as well. So the decision-making behavior of traffic administrations and drivers can be converted into a double game model. And through quantification of their earnings in different choice conditions, the optimum decision-making plan under specific conditions could be solved via the Nash equilibrium solution concept. Thus the results will provide a basis for the formulation of the traffic management strategy.
Evaluation of Deployment Challenges of Wireless Sensor Networks at Signalized Intersections
Azpilicueta, Leyre; López-Iturri, Peio; Aguirre, Erik; Martínez, Carlos; Astrain, José Javier; Villadangos, Jesús; Falcone, Francisco
2016-01-01
With the growing demand of Intelligent Transportation Systems (ITS) for safer and more efficient transportation, research on and development of such vehicular communication systems have increased considerably in the last years. The use of wireless networks in vehicular environments has grown exponentially. However, it is highly important to analyze radio propagation prior to the deployment of a wireless sensor network in such complex scenarios. In this work, the radio wave characterization for ISM 2.4 GHz and 5 GHz Wireless Sensor Networks (WSNs) deployed taking advantage of the existence of traffic light infrastructure has been assessed. By means of an in-house developed 3D ray launching algorithm, the impact of topology as well as urban morphology of the environment has been analyzed, emulating the realistic operation in the framework of the scenario. The complexity of the scenario, which is an intersection city area with traffic lights, vehicles, people, buildings, vegetation and urban environment, makes necessary the channel characterization with accurate models before the deployment of wireless networks. A measurement campaign has been conducted emulating the interaction of the system, in the vicinity of pedestrians as well as nearby vehicles. A real time interactive application has been developed and tested in order to visualize and monitor traffic as well as pedestrian user location and behavior. Results show that the use of deterministic tools in WSN deployment can aid in providing optimal layouts in terms of coverage, capacity and energy efficiency of the network. PMID:27455270
Game theory model of traffic participants within amber time at signalized intersection.
Qi, Weiwei; Wen, Huiying; Fu, Chuanyun; Song, Mo
2014-01-01
The traffic light scheme is composed of red, green, and amber lights, and it has been defined clearly for the traffic access of red and green lights; however, the definition of that for the amber light is indistinct, which leads to the appearance of uncertainty factors and serious traffic conflicts during the amber light. At present, the traffic administrations are faced with the decision of whether to forbid passing or not during the amber light in the cities of China. On one hand, it will go against the purpose of setting amber lights if forbidding passing; on the other hand, it may lead to a mess of traffic flow running if not. And meanwhile the drivers are faced with the decision of passing the intersection or stopping during the amber light as well. So the decision-making behavior of traffic administrations and drivers can be converted into a double game model. And through quantification of their earnings in different choice conditions, the optimum decision-making plan under specific conditions could be solved via the Nash equilibrium solution concept. Thus the results will provide a basis for the formulation of the traffic management strategy.
Evaluation of Deployment Challenges of Wireless Sensor Networks at Signalized Intersections.
Azpilicueta, Leyre; López-Iturri, Peio; Aguirre, Erik; Martínez, Carlos; Astrain, José Javier; Villadangos, Jesús; Falcone, Francisco
2016-07-22
With the growing demand of Intelligent Transportation Systems (ITS) for safer and more efficient transportation, research on and development of such vehicular communication systems have increased considerably in the last years. The use of wireless networks in vehicular environments has grown exponentially. However, it is highly important to analyze radio propagation prior to the deployment of a wireless sensor network in such complex scenarios. In this work, the radio wave characterization for ISM 2.4 GHz and 5 GHz Wireless Sensor Networks (WSNs) deployed taking advantage of the existence of traffic light infrastructure has been assessed. By means of an in-house developed 3D ray launching algorithm, the impact of topology as well as urban morphology of the environment has been analyzed, emulating the realistic operation in the framework of the scenario. The complexity of the scenario, which is an intersection city area with traffic lights, vehicles, people, buildings, vegetation and urban environment, makes necessary the channel characterization with accurate models before the deployment of wireless networks. A measurement campaign has been conducted emulating the interaction of the system, in the vicinity of pedestrians as well as nearby vehicles. A real time interactive application has been developed and tested in order to visualize and monitor traffic as well as pedestrian user location and behavior. Results show that the use of deterministic tools in WSN deployment can aid in providing optimal layouts in terms of coverage, capacity and energy efficiency of the network.
Drivers' smart advisory system improves driving performance at STOP sign intersections
Qing Li
2017-06-01
Full Text Available STOP signs are often physically blocked by obstacles at the corner, forming a safety threat. To enhance the safety at an un-signalized intersection like a STOP sign intersection, a radio frequency identification (RFID based drivers smart advisory system (DSAS was developed, which provides drivers with an earlier warning message when they are approaching an un-signalized intersection. In this research, a pilot field test was conducted with the DSAS alarm on an approach towards a STOP sign intersection in a residential area in Houston, Texas. The designed test route covers all turning movements, including left turn, through movement, and right turn. GPS units recorded test drivers' driving behaviors. A self-developed MATLAB program and statistically significant difference t-test were applied to analyze the impacts of the DSAS messages on drivers' driving performance, in terms of approaching speed profile, acceleration/deceleration rates, braking distance, and possible extra vehicle emissions induced by the introduction of the DSAS message. Drivers' preference on the DSAS was investigated by a designed survey questionnaire among test drivers. Results showed that the DSAS alarm was able to induce drivers to drive significantly slower to approach a STOP sign intersection, perform smaller fluctuation in acceleration/deceleration rates, and be more aware of a coming STOP sign indicated by decelerating earlier. All test drivers preferred to follow the DSAS alarm on roads for a safety concern. Further, the DSAS alarm caused the reduction in emission rates through movement. For a general observation, more road tests with more participants and different test routes were recommended.
Deadly crosstalk: Notch signaling at the intersection of EMT and cancer stem cells.
Espinoza, Ingrid; Miele, Lucio
2013-11-28
Notch signaling is an evolutionarily conserved pathway involved in cell fate control during development, stem cell self-renewal and postnatal tissue differentiation. Roles for Notch in carcinogenesis, in the biology of cancer stem cells, tumor angiogenesis and epithelial-to-mesenchymal transition (EMT) have been reported. This mini-review describes the role of Notch signaling deregulation in EMT and tumor aggressiveness. We describe how accumulated evidence suggests that Notch inhibition is an attractive strategy for the treatment of several cancers, at least in part because of its potential to reverse or prevent EMT.
AUXIN RESPONSE FACTOR 2 Intersects Hormonal Signals in the Regulation of Tomato Fruit Ripening.
Breitel, Dario A; Chappell-Maor, Louise; Meir, Sagit; Panizel, Irina; Puig, Clara Pons; Hao, Yanwei; Yifhar, Tamar; Yasuor, Hagai; Zouine, Mohamed; Bouzayen, Mondher; Granell Richart, Antonio; Rogachev, Ilana; Aharoni, Asaph
2016-03-01
The involvement of ethylene in fruit ripening is well documented, though knowledge regarding the crosstalk between ethylene and other hormones in ripening is lacking. We discovered that AUXIN RESPONSE FACTOR 2A (ARF2A), a recognized auxin signaling component, functions in the control of ripening. ARF2A expression is ripening regulated and reduced in the rin, nor and nr ripening mutants. It is also responsive to exogenous application of ethylene, auxin and abscisic acid (ABA). Over-expressing ARF2A in tomato resulted in blotchy ripening in which certain fruit regions turn red and possess accelerated ripening. ARF2A over-expressing fruit displayed early ethylene emission and ethylene signaling inhibition delayed their ripening phenotype, suggesting ethylene dependency. Both green and red fruit regions showed the induction of ethylene signaling components and master regulators of ripening. Comprehensive hormone profiling revealed that altered ARF2A expression in fruit significantly modified abscisates, cytokinins and salicylic acid while gibberellic acid and auxin metabolites were unaffected. Silencing of ARF2A further validated these observations as reducing ARF2A expression let to retarded fruit ripening, parthenocarpy and a disturbed hormonal profile. Finally, we show that ARF2A both homodimerizes and interacts with the ABA STRESS RIPENING (ASR1) protein, suggesting that ASR1 might be linking ABA and ethylene-dependent ripening. These results revealed that ARF2A interconnects signals of ethylene and additional hormones to co-ordinate the capacity of fruit tissue to initiate the complex ripening process.
Bicycle Conversion Factor Calibration at Two-Phase Intersections in Mixed Traffic Flows
WANG Dianhai; LIANG Chunyan; JING Chunguang; WANG Guohua
2007-01-01
Chinese traffic is typically composed of bicycles and motor vehicles on the same road. The efficiency of bicycle traffic in time and space at intersections was investigated for eight typical intersections in the cities of Tianjin, Shenyang, and Changchun, all in China, by means of video recording. Models were developed to calculate the through bicycle traffic and the left-turn bicycle traffic conversion factors in intersections where bicycles and motor vehicles share the same road. The results indicate that the through bicycle conversion factor is 0.28 and the left-turn bicycle conversion factor is 0.33. This conclusion differs from the current value used in China. More research on the conversion factor is necessary to evaluate the impact of intersections.
AUXIN RESPONSE FACTOR 2 Intersects Hormonal Signals in the Regulation of Tomato Fruit Ripening.
Dario A Breitel
2016-03-01
Full Text Available The involvement of ethylene in fruit ripening is well documented, though knowledge regarding the crosstalk between ethylene and other hormones in ripening is lacking. We discovered that AUXIN RESPONSE FACTOR 2A (ARF2A, a recognized auxin signaling component, functions in the control of ripening. ARF2A expression is ripening regulated and reduced in the rin, nor and nr ripening mutants. It is also responsive to exogenous application of ethylene, auxin and abscisic acid (ABA. Over-expressing ARF2A in tomato resulted in blotchy ripening in which certain fruit regions turn red and possess accelerated ripening. ARF2A over-expressing fruit displayed early ethylene emission and ethylene signaling inhibition delayed their ripening phenotype, suggesting ethylene dependency. Both green and red fruit regions showed the induction of ethylene signaling components and master regulators of ripening. Comprehensive hormone profiling revealed that altered ARF2A expression in fruit significantly modified abscisates, cytokinins and salicylic acid while gibberellic acid and auxin metabolites were unaffected. Silencing of ARF2A further validated these observations as reducing ARF2A expression let to retarded fruit ripening, parthenocarpy and a disturbed hormonal profile. Finally, we show that ARF2A both homodimerizes and interacts with the ABA STRESS RIPENING (ASR1 protein, suggesting that ASR1 might be linking ABA and ethylene-dependent ripening. These results revealed that ARF2A interconnects signals of ethylene and additional hormones to co-ordinate the capacity of fruit tissue to initiate the complex ripening process.
Endo, Tsutomu; Romer, Katherine A; Anderson, Ericka L; Baltus, Andrew E; de Rooij, Dirk G; Page, David C
2015-05-05
Mammalian spermatogenesis--the transformation of stem cells into millions of haploid spermatozoa--is elaborately organized in time and space. We explored the underlying regulatory mechanisms by genetically and chemically perturbing spermatogenesis in vivo, focusing on spermatogonial differentiation, which begins a series of amplifying divisions, and meiotic initiation, which ends these divisions. We first found that, in mice lacking the retinoic acid (RA) target gene Stimulated by retinoic acid gene 8 (Stra8), undifferentiated spermatogonia accumulated in unusually high numbers as early as 10 d after birth, whereas differentiating spermatogonia were depleted. We thus conclude that Stra8, previously shown to be required for meiotic initiation, also promotes (but is not strictly required for) spermatogonial differentiation. Second, we found that injection of RA into wild-type adult males induced, independently, precocious spermatogonial differentiation and precocious meiotic initiation; thus, RA acts instructively on germ cells at both transitions. Third, the competencies of germ cells to undergo spermatogonial differentiation or meiotic initiation in response to RA were found to be distinct, periodic, and limited to particular seminiferous stages. Competencies for both transitions begin while RA levels are low, so that the germ cells respond as soon as RA levels rise. Together with other findings, our results demonstrate that periodic RA-STRA8 signaling intersects with periodic germ-cell competencies to regulate two distinct, cell-type-specific responses: spermatogonial differentiation and meiotic initiation. This simple mechanism, with one signal both starting and ending the amplifying divisions, contributes to the prodigious output of spermatozoa and to the elaborate organization of spermatogenesis.
Guoqiang Zhang
2017-01-01
Full Text Available Traffic conflicts were used to evaluate safety performance of a three-leg unsignalized intersection. With the aid of a video camera, data were collected at the intersection and 15-second time span was used in each observation to overcome the drawbacks of traditional methods of traffic conflict analysis. Time to collision (TTC, a widely accepted indicator, was used to identify whether an interaction between two vehicles was a traffic conflict. By using Poisson regression, a prediction model for traffic conflicts at the intersection was developed. Based upon the model, assuming that other factors remain constant, when time headway or speed of eastbound traffic on major road, which is crossed by left-turning traffic from minor road, increases, the number of traffic conflicts at the intersection decreases. When volume of left-turning traffic on minor road or speed of left-turning vehicles on minor road increases, the number of traffic conflicts at the intersection increases if other factors remain constant. Explanations for the influence of the factors, which were represented by independent variables of the prediction model, were then analyzed in detail.
Pedestrians´and cyclists´effect on capacity of right turn movement at signalized intersections
Aagaard, Pierre E.; Rysgaard, Rikke; Jørgensen, N O
1998-01-01
Observations from 4 intersections in Copenhagen are used to formulate a model for the delays which right turning car traffic experience due to straight ahead going pedestrians and cyclists. The empirical data are used to formulate a simulation model which allows estimation of delays in cases...
To signal or not to signal: that should not be the question.
Faw, Harold W
2013-10-01
The purpose of the present research was to examine rates of turn signal use, a positive and potentially valuable means by which drivers can communicate. A second purpose was to explore factors that might impact these rates, including the modeling influence of other drivers. A series of observations involving more than 5600 vehicles making turns were recorded at a variety of intersections in British Columbia, Canada. Though the occurrence of signal use varied widely, ranging from a low of 54% to a high of 95%, the overall rate was 76%. Drivers used turn signals significantly less often when making right as compared with left turns, when traffic volume was higher, and when a designated turning lane was provided. In addition, compared with drivers following another vehicle not using signals, those following a vehicle with turn signals on were significantly more likely to activate their turn signals, suggesting a possible modeling effect. Both internal and external influences on turn signal use by drivers were considered. External factors explored in this research included direction of turn, traffic volume, intersection configuration, and the example of other drivers. It was concluded that the practice of signaling turns merits more research attention, since consistent use of signals is a potential contributor to enhanced safety for all road users. Copyright © 2013 Elsevier Ltd. All rights reserved.
Zhang, Hong-Ze; Jiang, Rui; Hu, Mao-Bin; Jia, Bin
2017-02-01
The traffic delay at intersections is crucial for the performance of urban traffic system. This paper analytically investigated the minimum traffic delay at a three-phase T-type intersection. We firstly demonstrate that the minimum traffic delay must be achieved on the surface of the 3D space constituted by the three constraints. Next, we prove that the minimum traffic delay must be achieved on the three borderlines of the surface. Finally, we show that the minimum delay is achieved either on one specific borderline or at the vertex of the surface. In the former case, extra green time is needed for the stream with largest demand, while no extra green time should be assigned to any stream in the latter case.
无灯控错位交叉口交通流模型研究%Traffic Flow Model for Staggered Intersection without Signal Lamp
刘小明; 郑淑晖
2012-01-01
错位交叉口交通特性研究对于制定合理有效的错位交叉口交通管控策略具有重要意义.针对无灯控错位交叉口交通流间的冲突过程分别建立了相应的元胞自动机行为规则,进而应用上述规则对不同参数设置下的交通流演化过程进行数值模拟,并分析和讨论了主路进口道交通流密度变化对不同路段交通流平均速度的影响.研究结果表明,错位交叉口主路上较小的车流密度也能导致主路进口道及两T型口中间路段发生交通堵塞,每个T型口主路进口道交通流量变化会对另一个T型口主路进口道交通流平均速度产生较大影响,此外,无灯控下的交通堵塞也会呈现周期性的排队-消散过程.上述方法及结果可为错位交叉口实施信号控制提供有意义的指导.%Traffic characteristics investigation of staggered intersection lays the foundation of scientific and reasonable traffic control strategies. This paper first proposes the cellular automaton rules on the basis of the traffic conflict process analysis. Then with these rules, the traffic flow evolution under different parameters is presented by numerical simulations. The relationship between the arterial road traffic flow density and the average speed is explored. It is revealed that low traffic density on the main road of staggered intersections may lead to traffic congestions on the approach of main road and the road between two T-type intersections, and the average speed of traffic flow on each T-type import of main road was affected by the traffic flow changes of the other T-type approaches. Moreover, the traffic congestion on intersection without signal lamp is presented as a periodically queuing-dissipates process. The above methods and results provide meaningful guidance for traffic management and control implementation of staggered intersections without signal lamp.
Marfelt, Mikkel Mouritz
2016-01-01
oriented but still emphasizes stable concepts. Moreover, it does not give primacy to oppression. Finally, it adopts a critical stance on the nature of the macro, meso, and micro levels as dominant analytical perspectives. As a result, this paper focusses on the importance of intersectionality...
Barbara Harbin Cobb
2009-01-01
<正>I’m a few years older than the People’s Re- public of China, but hardly an infant compared to China’s vast history and culture. China and I have intersected at many points, and I want to tell you about a few of them.
Ferrara, S; Morales, J F; Samtleben, H
2009-01-01
We apply the entropy formalism to the study of the near-horizon geometry of extremal black p-brane intersections in D>5 dimensional supergravities. The scalar flow towards the horizon is described in terms an effective potential given by the superposition of the kinetic energies of all the forms under which the brane is charged. At the horizon active scalars get fixed to the minima of the effective potential and the entropy function is given in terms of U-duality invariants built entirely out of the black p-brane charges. The resulting entropy function reproduces the central charges of the dual boundary CFT and gives rise to a Bekenstein-Hawking like area law. The results are illustrated in the case of black holes and black string intersections in D=6, 7, 8 supergravities where the effective potentials, attractor equations, moduli spaces and entropy/central charges are worked out in full detail.
Simulation model for analyzing SPUDI with actuated signals
Shafahi, Y.; Haghani, A.; Carter, E.C. [Univ. of Maryland, College Park, MD (United States). Dept. of Civil Engineering; Gupta, K.N.V. [SIMCO Engineering, New York, NY (United States)
1998-09-01
A time based microsimulation model is developed for analyzing the traffic operation at single point urban diamond interchanges. Features of the model include actuated signal operation, protected and permitted left turn phasing, right turn phasing with and without right turn on red, traffic in shared lanes, traffic in left turn and right turn storage lanes, car following, lane changing, gap acceptance behavior, primary and secondary queue formation and dissipation. The model accepts geometric, traffic, and signal data in an interactive mode. Input files may also be created separately without going through the interactive session. The model outputs include measures of effectiveness such as stopped delay, total delay, average speed, and maximum and average queue length. These measures of effectiveness are given for each turning movement for each approach, and for the intersection as a whole. The model outputs also show the total green time and the total yellow and all red times assigned by the actuated system to each phase during the simulation time. The model results are compared with the actual data collected in the field.
Kowalewski, Markus; Dorfman, Konstantin E; Mukamel, Shaul
2015-01-01
Conical intersections (CoIn) dominate the pathways and outcomes of virtually all photophysical and photochemical molecular processes. Despite extensive experimental and theoretical effort, CoIns have not been directly observed yet and the experimental evidence is being inferred from fast reaction rates and some vibrational signatures. We show that short X-ray (rather than optical) pulses can directly detect the passage through a CoIn with the adequate temporal and spectral sensitivity. The technique is based on a coherent Raman process that employs a composite femtosecond/attosecond X-ray pulse to detect the electronic coherences (rather than populations) that are generated as the system passes through the CoIn.
Borel, Armand
1984-01-01
This book is a publication in Swiss Seminars, a subseries of Progress in Mathematics. It is an expanded version of the notes from a seminar on intersection cohomology theory, which met at the University of Bern, Switzerland, in the spring of 1983. This volume supplies an introduction to the piecewise linear and sheaf-theoretic versions of that theory as developed by M. Goresky and R. MacPherson in Topology 19 (1980), and in Inventiones Mathematicae 72 (1983). While some familiarity with algebraic topology and sheaf theory is assumed, the notes include a self-contained account of further material on constructibility, derived categories, Verdier duality, biduality, and on stratified spaces, which is used in the second paper but not found in standard texts. "The volume should be useful to someone interested in acquiring some basic knowledge about the field..." —Mathematical Reviews.
Bennett, Kochise; Kowalewski, Markus; Dorfman, Konstantin; Mukamel, Shaul
Conical intersections (CIs) dominate the pathways and outcomes of virtually all photochemical molecular processes. Despite extensive experimental and theoretical effort, CIs have not been directly observed yet and the experimental evidence is inferred from fast reaction rates and vibrational signatures. We show that short X-ray pulses can directly detect the passage through a CI with the adequate temporal and spectral sensitivity. The non-adiabatic coupling that exists in the region of a CI redistributes electronic population but also generates electronic coherence. This coherent oscillation can then be detected via a coherent Raman process that employs a composite femtosecond/attosecond X-ray pulse. This technique, dubbed Transient Redistribution of Ultrafast Electronic Coherences (TRUECARS) is reminiscent of Coherent Anti-Stokes Raman Spectroscopy (CARS) in that a coherent oscillation is set in motion and then monitored, but differs in that the dynamics is electronic (CARS generally observes nuclear dynamics) and the coherence is generated internally by passage through a region of non-adiabatic coupling rather than by an externally applied laser. Support provided by U.S. Department of Energy through Award No. DE-FG02-04ER15571, the National Science Foundation (Grant No CHE-1361516), and the Alexander von Humboldt foundation through the Feodor Lynen program.
Fu, Chuanyun; Zhang, Yaping; Bie, Yiming; Hu, Liwei
2016-10-01
Countdown timers display the time left on the current signal, which makes drivers be more ready to react to the phase change. However, previous related studies have rarely explored the effects of countdown timer on driver's brake perception-reaction time (BPRT) to yellow light. The goal of this study was therefore to characterize and model driver's BPRT to yellow signal at signalized intersections with and without countdown timer. BPRT data for "first-to-stop" vehicles after yellow onset within the transitional zone were collected through on-site observation at six signalized intersections in Harbin, China. Statistical analysis showed that the observed 15th, 50th, and 85th percentile BPRTs without countdown timer were 0.52, 0.84, and 1.26s, respectively. The observed 15th, 50th, and 85th percentile BPRTs with countdown timer were 0.32, 1.20, and 2.52s, respectively. Log-logistic distribution appeared to best fit the BPRT without countdown timer, while Weibull distribution seemed to best fit the BPRT with countdown timer. After that, a Log-logistic accelerated failure time (AFT) duration model was developed to model driver's BPRT without countdown timer, whereas a Weibull AFT duration model was established to model driver's BPRT with countdown timer. Three significant factors affecting the BPRT identified in both AFT models included yellow-onset distance from the stop line, yellow-onset approach speed, and deceleration rate. No matter whether the presence of countdown timer or not, BPRT increased as yellow-onset distance to the stop line or deceleration rate increased, but decreased as yellow-onset speed increased. The impairment of driver's BPRT due to countdown timer appeared to increase with yellow-onset distance to the stop line or deceleration rate, but decrease with yellow-onset speed. An increase in driver's BPRT because of countdown timer may induce risky driving behaviors (i.e., stop abruptly, or even violate traffic signal), revealing a weakness of
Turk, Edward M.; Fujioka, Shozo; Seto, Hideharu; Shimada, Yukihisa; Takatsuto, Suguru; Yoshida, Shigeo; Denzel, Megan A.; Torres, Quetzal I.; Neff, Michael M.
2003-01-01
Active brassinosteroids, such as brassinolide (BL) and castasterone, are growth promoting plant hormones. An Arabidopsis cytochrome P450 monooxygenase encoded by CYP72B1 has been implicated in brassinosteroid catabolism as well as photomorphogenesis. We expressed CYP72B1 in yeast, coupled with brassinosteroid feeding, and established the biochemical function to be the hydroxylation of BL and castasterone, to give 26-hydroxybrassinolide and 26-hydroxycastasterone, respectively. Brassinosteroid feeding experiments with wild-type Arabidopsis, a CYP72B1 null mutant, and a CYP72B1 overexpression line demonstrated that carbon 26 hydroxylation of active brassinosteroids is an endogenous function of CYP72B1. Seedling growth assays demonstrated that 26-hydroxybrassinolide is an inactive brassinosteroid. Genetic and physiological analysis of the hypocotyl response to exogenous BL and varying intensities of white and monochromatic light suggested that CYP72B1 modulates photomorphogenesis primarily through far-red light and to a lesser extent through blue- and red-light pathways. CYP72B1 transcript accumulation in dark-grown seedlings was organ specific and down-regulated after 1 h of illumination in dim white, red, and blue light, but not far-red light. CYP72B1 translational fusions with the β-glucuronidase reporter gene demonstrated that protein levels increased in the hypocotyl elongation zone when shifted from the dark to far-red light, but not blue or red light. We propose a model in which Arabidopsis seedling development switches from dark-grown development (skotomorphogenesis) to light-grown development (photomorphogenesis) in part by rapid modulation of brassinosteroid sensitivity and levels. CYP72B1 provides an intersection between the light and brassinosteroid pathways mainly by far-red-light-dependent modulation of brassinosteroid levels. PMID:14605216
王雪松; 谢琨; 陈小鸿; 王珂
2012-01-01
Generalized estimating equation (GEE) was applied to account for the correlation among intersections from corridors. Risk factors including intersection location, geometric design, signal control, and operation condition were identified. The results show that GEE with the autoregressive correlation structure is the most effective way to deal with the spatially correlated data. It confirms that intersections in close proximity, with greater ratio of turning lanes, more number of phrases, and more ADT tend to have higher crash frequencies; 4-legged intersections and intersections under elevated expressways are associated with more crashes.%利用广义估计方程(generalized estimating equation,GEE)考虑交叉口的空间相关性,分析交叉口所处位置、几何设计、信号控制、运行状况等因素对于安全的影响.结果表明,以自回归型(autoregressive)为关联矩阵的GEE模型具有最优的拟合效果;交叉口间距越小、转向车道比例越大、相位数越多、日均流量越大,事故产生的风险越大；十字交叉口、低交通密度、位于高架下的交叉口的事故发生几率较高.
Safety Impacts of Push-Button and Countdown Timer on Nonmotorized Traffic at Intersections
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.
龙科军; 赵文秀; 肖向良
2011-01-01
Drivers decision to go or stop during the yellow interval belongs to uncertain decision making. This paper collects drivers behavior data at four similar intersections. Fuzzy Decision Tree(FDT) is applied to model driver behavior at signalized intersection. Considering vehicle location,velocity and countdown timer as the influencing factors, the FDT model is constructed using FID3 algorithm, and decision roles are generated as well. Test sample is applied to test FDT model, and results indicate that FDT model can predict drivers' decision with overall accuracy of 84.8％.%采集黄灯期间驾驶员行为的相关数据,考虑车辆位置、车速、倒计时表3个影响因素,分别设定其隶属度函数,应用模糊决策树中的FID3算法,以模糊信息熵为启发信息,构建驾驶员选择的模糊决策树模型,生成决策规则.利用测试样本对模型进行检验,结果表明,基于模糊决策树的预测结果准确率总体达到84.8%.
Signal Timing Optimization of BRT Station near Intersection%BRT车站濒临交叉口的信号配时优化算法研究及应用
郑淑鉴; 徐建闽
2011-01-01
For BRT stations in the vicinity of intersection, the signal control of the upstream intersection affects the queue and delay of the downstream station. By minimizing the total delay of vehicles at the station and in the intersection, an intersection signal timing optimization algorithm is established with dynamic control of traffic flow and implemented by using Visual Basic. Finally, taking Chebei Intersection and Chebei Station of the BRT of Zhongshan Road in Guangzhou as an example, the paper verifies the algorithm by VISSIM simulation. The simulation results show that the algorithm is effective and practical to achieve the minimum total delay of the vehicles.%当BRT车站濒临交叉口时,上游交叉口的信号控制易影响下游车站的进站排队,进而影响车辆在车站的延误;以车辆在交叉口的延误和在车站的延误总和最小为目标,采用动力学、信号控制和交通流等方法建立交叉口的信号配时优化算法,并用Visual Basic实现算法.以广州市中山大道BRT的车陂交叉口与车陂站为案例,用Vissim仿真验证算法.仿真结果表明算法的正确性与实用性,实现了车辆的总延误最小.
Identification and optimization of traffic bottleneck with signal timing
Shaoxin Yuan
2014-10-01
Full Text Available In urban transportation network, traffic congestion is likely to occur at traffic bottlenecks. The signal timing at intersections together with static properties of left-turn and straight-through lanes of roads are two significant factors causing traffic bottlenecks. A discrete-time model of traffic bottleneck is hence developed to analyze these two factors, and a bottleneck indicator is introduced to estimate the comprehensive bottleneck degree of individual road in regional transportation networks universally, the identification approaches are presented to identify traffic bottlenecks, bottleneck-free roads, and bottleneck-prone roads. Based on above work, the optimization method applies ant colony algorithm with effective green time as decision variables to find out an optimal coordinated signal timing plan for a regional network. In addition, a real experimental transportation network is chosen to verify the validation of bottleneck identification. The bottleneck identification approaches can explain the features of occurrence and dissipation of traffic congestion in a certain extent, and the bottleneck optimization method provides a new way to coordinate signal timing at intersections to mitigate traffic congestion.
吴建平; 黄岭; 赵坚利
2004-01-01
Investigations have been carried out at a signalized intersection in Beijing to study the behavior of cyclists and pedestrians in mixed traffic situations. Video cameras and data analysis technologies have been used to collect and analyze image data of cyclists and pedestrians at the signalized intersection. Results are useful for understanding the performance of mixed traffic at signalized intersections, and for building microscopic simulation models for urban mixed traffic.%对北京市信号交叉口的自行车和行人在混和交通流中的微观行为进行研究分析.研究中使用视频采集技术和数据分析技术来收集和分析自行车和行人在交叉口的行为.论文的主要研究结果是信号交叉口自行车和行人的各种微观行为特征和基础行为模型,这些结果有助于理解信号交叉口混和交通流的行为,并为城市混和交通流的微观交通模拟模型提供基础数据和理论依据.
INTERSECTIONAL DISCRIMINATION AGAINST CHILDREN
Ravnbøl, Camilla Ida
This paper adds a perspective to existing research on child protection by engaging in a debate on intersectional discrimination and its relationship to child protection. The paper has a twofold objective, (1) to further establish intersectionality as a concept to address discrimination against ch...... children, and (2) to illustrate the importance of addressing intersectionality within rights-based programmes of child protection....
Deburring small intersecting holes
Gillespie, L.K.
1980-08-01
Deburring intersecting holes is one of the most difficult deburring tasks faced by many industries. Only 14 of the 37 major deburring processes are applicable to most intersecting hole applications. Only five of these are normally applicable to small or miniature holes. Basic process capabilities and techniques used as a function of hole sizes and intersection depths are summarized.
Delay model of multi-state flow for intersection timing signal control%多态交通条件下交叉口定时控制延误模型
丁恒; 陈无畏; 郑小燕; 马晓
2012-01-01
The delay is the essential evaluation index of intersection service level, and delay model plays an important role in intersection signal timing. In the condition of multi-state traffic flow, the existing delay models possess a large error. In order to adapt to the multi-sate flow, arriving headway data of intersection is fit based on the denseness of mixture Gamma distribution, and the probability of traffic flow arriving at intersection is calculated by means of fit probability function. Furthermore, the intersections are separated into two classes with traffic flow, low saturation and over saturation, and intersection timing control delay model on the traffic flow statistic probability is put forward. Finally, a reality intersection is presented as an example, and the result shows that the delay calculated by the model based on mixture Gamma distribution is close to practice.%延误是评价交叉口服务水平的基本指标,延误模型对交叉口信号控制方案的选择意义重大.在多态交通条件下,采用现有模型分析信号控制下交叉口延误程度存在较大误差.为适应交叉口交通流的多态性,基于混合Gamma分布稠密性,准确拟合交叉口到达车头时距数据.运用拟合概率函数,统计交叉口进口到达交通量概率.将交叉口按照到达交通量大小分为欠饱和、过饱和两种状态,根据统计概率提出交叉口信号定时控制延误模型.实例分析表明.基于混合Gamma分布的延误与实际结果更为吻合.
臧利林; 朱文兴
2012-01-01
In order to reduce average delay time of passing vehicles and improve urban area traffic efficiency, considering actual geographical characteristics of intersections and sub-area traffic data, a control model for traffic signals at intersections was built based on optimizing sub-area traffic flows, and genetic algorithm was used to find out the optimal solution of the model. With traffic signals coordination of neighboring intersections considered, vehicle minimal delay time was chosen as the optimization object in the model. HCM2000 was adopted to calculate vehicle delay time and Robertson model was embedded in the optimization procedure, which ensured the proposed model to be feasible and effective. VC+ 3- 6. 0 software was applied to programm and calculate an optimal control plan for traffic signals at intersections. Finally, simulation by CORSIM was implemented to verifythe validity of the control plan. The results show that the proposed model can obtain better traffic efficiency than the coordination control method based on existing common cycle, and provides a new signal control idea at intersections for urban traffic.%为了减少车辆平均延误时间,提高城市区域交通通行效率,结合实际交叉口地理特征和区域交通流数据,建立了一种基于子区域交通流优化的交叉口信号控制模型,并应用遗传算法获得模型的最优解。在模型中,考虑相邻交叉口信号之间的协调,以车辆平均延误时间最小为优化目标,采用HCM2000延误计算方法,并在优化过程中嵌入Robertson车队离散模型,保证提出模型的可行性和有效性。在VC＋＋6.0中编写程序,获得交叉口信号最优控制方案,最后通过CORSIM仿真证明该控制方案的优劣。结果表明：与现有基于共同周期的协调控制方法相比,所提出的模型能够获得更优的交通效益,为区域交通信号控制提供了一种新的思路。
Analysis of Drivers'Behavior at Signalized Intersection%信号交叉口驾驶员行为博弈分析
黄选伟; 汪晶; 张邻
2015-01-01
为了研究车辆通过信号交叉口时的驾驶员决策行为,从博弈角度出发,根据影响驾驶员决策行为的性格因素,以及不同策略之间的势因素,通过时间细化,建立基于重复博弈下影响驾驶员决策行为的效用函数.通过驾驶员在行进过程中的决策行为,分析驾驶员获得的效用,得到动态博弈中驾驶员的最优决策.同时通过实例验证模型的可行性.例证表明:第一,对于冲动型的驾驶员在决策初始时刻最可能选择减速策略;第二,温和型的驾驶员选择加速或减速策略;第三,谨慎型的驾驶员选择减速策略.%In order to study the decision-making behavior of drivers at the signalized intersection, this study estab-lishes a utility function of drivers' driving behavior by reference to dynamic reduplicate game theory based on the drivers'personality that affects decision-making behavior and time refinement, and the relative potential factors among different strategies . According to the drivers'decision-making behavior in the process of driving and ana-lyzing the utility of the drivers'decision-making behavior, the drivers'optimal decision behaviors in a dynamic game are obtained, and the feasibility of the model is simultaneously verified. Experiments show that during deci-sion-making①impulsive drivers are more willing to choose deceleration strategy;②mild drivers prefer accelera-tion strategy or deceleration strategy;and③cautious drivers choose deceleration strategy.
Statistical modeling of total crash frequency at highway intersections
Arash M. Roshandeh
2016-04-01
Full Text Available Intersection-related crashes are associated with high proportion of accidents involving drivers, occupants, pedestrians, and cyclists. In general, the purpose of intersection safety analysis is to determine the impact of safety-related variables on pedestrians, cyclists and vehicles, so as to facilitate the design of effective and efficient countermeasure strategies to improve safety at intersections. This study investigates the effects of traffic, environmental, intersection geometric and pavement-related characteristics on total crash frequencies at intersections. A random-parameter Poisson model was used with crash data from 357 signalized intersections in Chicago from 2004 to 2010. The results indicate that out of the identified factors, evening peak period traffic volume, pavement condition, and unlighted intersections have the greatest effects on crash frequencies. Overall, the results seek to suggest that, in order to improve effective highway-related safety countermeasures at intersections, significant attention must be focused on ensuring that pavements are adequately maintained and intersections should be well lighted. It needs to be mentioned that, projects could be implemented at and around the study intersections during the study period (7 years, which could affect the crash frequency over the time. This is an important variable which could be a part of the future studies to investigate the impacts of safety-related works at intersections and their marginal effects on crash frequency at signalized intersections.
FL-FN-MOGA Based Traffic Signal Control
魏武; 张毅
2003-01-01
In this paper, a traffic signal control method based on fuzzy logic (FL), fuzzy-neuro (FN) and multi-objective genetic algorithms (MOGA) for an isolated four-approach intersection with through and left-turning movements is presented. This method has an adaptive signal timing ability, and can make adjustments to signal timing in response to observed changes. The "urgency degree" term, which can describe the different user's demand for green time is used in decision-making by which strategy of signal timing can be determined. Using a fuzzy logic controller, we can determine whether to extend or terminate the current signal phase and select the sequences of phases. In this paper, a method based on fuzzy-neuro can be used to predict traffic parameters used in fuzzy logic controller. The feasibility of using a multi-objective genetic algorithm (MOGA) to find a group of optimizing sets of parameters for fuzzy logic controller depending on different objects is also demonstrated. Simulation results show that the proposed methed is effecfive to adjust the signal timing in response to changing traffic conditions on a real-time basis, and the controller can produce lower vehicle delays and percentage of stopped vehicles than a traffic-actuated controller.
信号交叉口公交专用进口道设置条件与效果分析%Setting Condition and Effect Analysis of Bus Lanes at Signalized Intersection
吕斌; 牛惠民
2011-01-01
分析了已有公交优先策略评价与仿真方法的局限性,考虑不同的交通需求水平与信号配时参数,将车均延误、人均延误和车辆排队长作为单个信号交叉口运行评价指标,以三相位十字信号交叉口为例,利用Simio仿真分析了公交专用进口道设置前后上述评价指标的变化规律.结果可用于交叉口公交优先信号配时参数的优化.%The limitations of evaluation and simulation methods for the existed bus priority strategy are analyzed. Average vehicle delay, average delay of customers and queue length are taken as evaluation indexes. Considering different traffic demand and signal timing parameters, a simulation example of a three-phase signalized intersection is presented to experiment and analyze the change rule of evaluation index with and without bus lanes, respectively by using the object-oriented simulation software Simio. The study results can be used in optimization signal timing parameters of signalized intersection based on bus priority.
牟海波; 俞建宁; 刘林忠
2012-01-01
Under an unexpected event, emergency vehicles coming from different directions arrive at the same intersection simultaneously and compete for green light phase. To reduce intersection delays of emergency vehicles, taken the minimum delays of all vehicles at isolated intersection as the control target, the priority of each phase was obtained by considering expected future waiting times and emergency vehicle volume rate comprehensively. Fuzzy Petri net approach was adopted to give the most suitable green time of current phase according to the queue and the emergency vehicle volume rate of current phase and the next phase. Finally, a concrete signal priority control strategy was presented. Simulation result indicates that when the emergency vehicle volume rate increased from 0. 1 to 0. 6, the average intersection delay of emergency vehicles decreased from 22. 43 s to 20. 41 s, since the phase priority increased correspondingly and the assigned green time was close to the clearance time, some emergency vehicles can pass through the intersection directly. The strategy given here can reduce the intersection delays of emergency vehicles efficiently.%突发事件下,不同方向的应急车辆同时到达交叉口竞争绿灯相位.为减少应急车辆在交叉口的延误,以车辆总停留时间最小为目标,综合考虑各相位的期望将来停留时间和应急车流量比,得到各个相位的优先权.根据当前相位和下一相位的队长和应急车流量比,采用模糊Petri网方法确定当前相位的最佳绿灯时间,并给出了具体的信号优先控制策略.仿真结果表明,当应急车流量比由0.1增加到0.6时,由于对应相位的优先权增大,实际执行绿灯时间接近于相位清空时间,部分应急车辆可以不在交叉口停留直接通过,应急车辆的交叉口平均延误由22.43 s下降到20.41 s.可见,该方法可以有效降低应急车辆的交叉口延误.
Wu Yang YU; Dong Hua WU; Gang Song LENG
2007-01-01
The purpose of this paper is to generalize the notion of intersection bodies to that of quasi Lp-intersection bodies. The Lp-analogs of the Busemann intersection inequality and the Brunn Minkowski inequality for the quasi Lp-intersection bodies are obtained. The Aleksandrov-Fenchel inequality for the mixed quasi Lp-intersection bodies is also established.
INTERSECTIONAL DISCRIMINATION AGAINST CHILDREN
Ravnbøl, Camilla Ida
This paper adds a perspective to existing research on child protection by engaging in a debate on intersectional discrimination and its relationship to child protection. The paper has a twofold objective, (1) to further establish intersectionality as a concept to address discrimination against...
Elastic waves along a fracture intersection
Abell, Bradley Charles
Fractures and fracture networks play a significant role in the subsurface hydraulic connectivity within the Earth. While a significant amount of research has been performed on the seismic response of single fractures and sets of fractures, few studies have examined the effect of fracture intersections on elastic wave propagation. Intersections play a key role in the connectivity of a fracture network that ultimately affects the hydraulic integrity of a rock mass. In this dissertation two new types of coupled waves are examined that propagate along intersections. 1) A coupled wedge wave that propagates along a surface fracture with particle motion highly localized to the intersection of a fracture with a free surface, and 2) fracture intersection waves that propagate along the intersection between two orthogonal fractures. Theoretical formulations were derived to determine the particle motion and velocity of intersection waves. Vibrational modes calculated from the theoretical formulation match those predicted by group theory based on the symmetry of the problem. For the coupled wedge wave, two vibrational modes exist that range in velocity between the wedge wave and Rayleigh wave velocity and exhibit either wagging or breathing motion depending on the Poisson's ratio. For the intersection waves, the observed modes depend on the properties of the fractures forming the intersection. If both fractures have equal stiffness four modes exist, two with wagging and two with breathing motion. If the fractures have unequal stiffness, four modes also exist, but the motion depends on the Poisson's ratio. The velocity of intersection waves depends on the coupling or stiffness of the intersection and frequency of the signal. In general, the different modes travel with speeds between the wedge wave and bulk shear wave velocity. Laboratory experiments were performed on isotropic and anisotropic samples to verify the existence of these waves. For both waves, the observed signals
Trajectory Generation Model-Based IMM Tracking for Safe Driving in Intersection Scenario
Tingting Zhou
2011-01-01
Full Text Available Tracking the actions of vehicles at crossroads and planning safe trajectories will be an effective method to reduce the rate of traffic accident at intersections. It is to resolve the problem of the abrupt change because of the existence of drivers' voluntary choices. In this paper, we make approach of an improved IMM tracking method based on trajectory generation, abstracted by trajectory generation algorithm, to improve this situation. Because of the similarity between human-driving trajectory and programming trajectory which is generated by trajectory-generated algorithm, the improved IMM method performs well in tracking moving vehicles with some sudden changes of its movement. A set of data is collected for experiments when an object vehicle takes a sudden left turn in intersection scenario. To compare the experiment results between IMM method with trajectory generation model and the one without, tracking error of the former decreases by 75% in particular scenario.
Influences of driver’s attributions on signalized intersection traffic%驾驶员属性对信号灯路口交通流的影响研究
梅超群
2014-01-01
A cellular automaton model is proposed to study the traffic at signalized intersection. The driving behaviors induced by driver’s attribution (gender, driving experience, character, etc. ) are numerically analyzed. Simulation results show that the rusty driving skills or tension driving, impatient driving and so on can lead to the transition from free flow to congestion more easily, and these behaviors are the important cause for low travel efficiency at the intersection; the signal cycle is the main factor influencing traffic flux and travel time fairness.%采用元胞自动机模型研究信号灯路口的交通流特性，系统地分析了与性别、驾驶经验、性格等驾驶员属性相关的驾驶行为对交通流的影响。数值模拟发现，技术生疏或紧张驾驶、急躁行驶等驾驶行为更易引发自由流到阻塞流的相变，是路口通行低效率及事故隐患的重要原因，信号周期是影响流量与个人通行时间公平的主要因素。
曾滢; 杨晓光; 马莹莹
2009-01-01
基于信号控制交叉口时空关系分析,综合运用交通流理论和信号控制技术,建立了动态车道功能与信号相位组合模型,用Visual Basic语言编制程序对该模型求解.为验证模型的有效性,应用该模型对实际案例进行了优化,并通过交通仿真软件VISSIM分别对优化前后的方案进行了仿真对比分析.仿真结果表明:交叉口动态车道功能与信号控制存在协同作用,与仅改善车道功能或信号控制相比,实现两者的协同能有效提高交叉口时空资源的利用率,使关键状态参量如延误与排队长度显著降低.%Based on the analysis of space-time relation of signalized intersections,an integrated model for lane-use assignment and signal phase was established using the traffic flow theory and signal control technology synthetically.In order to solve the model,a program was developed through Visual Basic programming.Actual road intersections were optimized by the program and optimal solutions were generated.Then both the origin plan and the optimal solutions were simulated with VISSIM to verify the model.The simulation results show that there is synergetic effect between dynamic lane-use assignment and signal control.Different from improving lane-use assignment or signal plan alone,synergy cann effectively improve the utilization of space-time resources at intersections,thus reducing the key traffic state parameters such as delay and queue length.
Study on Optimization of Phase Offset at Adjacent Intersections
Yuanli GU
2010-11-01
Full Text Available Optimization of the phase offset at adjacent intersections is the key parameter regarding coordinated control of traffic signal for adjacent intersections, which decides the effect of the coordinated control for adjacent intersections. According to characters of saturated traffic flow of Chinese urban road, this thesis establishes a model for optimization of phase offset for adjacent interactions and finds a solution from such model by adopting genetic algorithm. The model is verified by actual traffic flow datum of two adjacent signal intersections on Changan Avenue. Then a comparison is made between the optimization result of such model and that of the existing mathematical method and SYNCHRO model, which indicates that the model established by this thesis can reduce the delay suffered by vehicles at the intersections and increase the traffic efficiency of the intersections.
相邻交叉口相聚度分析及应用%Intersection Signal Control Dynamic Decision-making Model and Its Optimization Method
首艳芳; 徐建闽; 卢凯
2012-01-01
The concept of meeting degree is introduced into group decision-making theory. The definition and calculation formula of adjacent intersections' meeting degree are presented through the analysis of various factors that influence the correlation between adjacent intersections. The calculation method and scientific rationality are elaborated. Furthermore, coordination control subarea division strategy based on meeting degree analysis is given. The results show that the proposed subarea division method is rational and scientific, and has practical value.%引入群决策理论中相聚度的概念,通过分析影响相邻交叉口相关性的各种因素,创造性地给出了相邻交叉口相聚度的定义及其计算公式,并对其计算方法和科学合理性进行了阐述,进一步给出了基于相聚度分析的协调控制子区划分策略.算例分析说明,基于相聚度的控制子区划分方法科学合理,具有一定的实用性.
城市灯控平面交叉口慢行交通时空违章特征研究%Slow Traffic Peccancy Character for Urban Signal Intersection
王庆; 陈学武; 周娇; 陈琳英
2012-01-01
在南京市内4个典型交叉口调查数据的基础上,通过对4 000多个行人样本数据和相应交叉口不同时间段的自行车违章数据的统计分析,得出了慢行交通的时空违章特征.行人个体违章在时空违章上有不同的表现形式,在不同交叉口存在很大的差异性；行人的违章行为与性别无关,与年龄有关,少年的违章比例最低.由于交叉口断面形式、信号配时、运行秩序、交通管制、周边环境等方面的因素,自行车的行驶方向平均违章率和违章性质平均违章率在不同交叉口存在很大的差异性.针对慢行交通违章者安全意识淡薄且违章成本较低、交叉口的设计不合理等原因,提出相应的预防和纠正违章的建议和措施.%It has been drawn out from statistical analysis on 4000 sample data of the peccancy of passerby at different intersection from the four model intersection in Nanjing that there is different behave forms in time and space for passby peccancy and great difference at each crossings. It relates to passerby age, but not to sex, e. G. The peccancy rate of teen-age is the lowest. There is great difference in peccancy of run way and behavior property by analysis on differ time sect bicycle date, which is related to some factors, such as road cross-section, traffic control, run order and surrounding environment. According to the main reason of slow traffic peccancy behavior, I. E. The actor's dim safety consciousness, low cost of peccany, srrationali intersecton design, corresponding suggestions and measures to prevent and correct traffic peccancy are proposed. The behavior character of slow traffic peccancy on the city s signal intersection would be a good reference for solving the urban signal intersection mixed traffic problems.
Aldazabal, G; Ibáñez, L E; Rabadan, Raul; Uranga, Angel M
2001-01-01
It is known that chiral fermions naturally appear at certain intersections of branes at angles. Motivated by this fact, we propose a string scenario in which different standard model gauge interactions propagate on different (intersecting) brane worlds, partially wrapped in the extra dimensions. Quarks and leptons live at brane intersections, and are thus located at different positions in the extra dimensions. Replication of families follows naturally from the fact that the branes generically intersect at several points. Gauge and Yukawa couplings can be computed in terms of the compactification radii. Hierarchical Yukawa couplings appear naturally, since amplitudes involving three different intersections are proportional to exp(-A_{ijk}), where A_{ijk} is the area of a string world-sheet extending among the intersections. The models are non-supersymmetric but the string scale may be lowered down to 1-10 TeV. The proton is however stable due to a set of discrete symmetries arising from world-sheet selection r...
Self-Localization at Street Intersections.
Fusco, Giovanni; Shen, Huiying; Coughlan, James M
2014-05-01
There is growing interest among smartphone users in the ability to determine their precise location in their environment for a variety of applications related to wayfinding, travel and shopping. While GPS provides valuable self-localization estimates, its accuracy is limited to approximately 10 meters in most urban locations. This paper focuses on the self-localization needs of blind or visually impaired travelers, who are faced with the challenge of negotiating street intersections. These travelers need more precise self-localization to help them align themselves properly to crosswalks, signal lights and other features such as walk light pushbuttons. We demonstrate a novel computer vision-based localization approach that is tailored to the street intersection domain. Unlike most work on computer vision-based localization techniques, which typically assume the presence of detailed, high-quality 3D models of urban environments, our technique harnesses the availability of simple, ubiquitous satellite imagery (e.g., Google Maps) to create simple maps of each intersection. Not only does this technique scale naturally to the great majority of street intersections in urban areas, but it has the added advantage of incorporating the specific metric information that blind or visually impaired travelers need, namely, the locations of intersection features such as crosswalks. Key to our approach is the integration of IMU (inertial measurement unit) information with geometric information obtained from image panorama stitchings. Finally, we evaluate the localization performance of our algorithm on a dataset of intersection panoramas, demonstrating the feasibility of our approach.
张东明; 成卫; 潘云伟; 肖海承
2011-01-01
The rapid development of science and technology to make intelligent transportation as an effective means to solve traffic problems, for the traffic flow phenomenon of morning and afternoon peak hour traffic and the direction of imbalance at intersection,the thought of traffic guidance is induced, made use of variable approach to solve traffic congestion during peak periods at the signalized intersection ,given the way of the data acquisition and the conditions of lanes change. Variable Message Sign (VMS) is used to display the information of lanes change in a timely manner,with the actual the intersection model is established,the same time,with rich API of the microscopic traffic simulation software-paramics to achieve the model simulation, the comparison and evaluation results are presented. The results show that the using of variable approach can significantly improve the intersection level of service.%科学技术的快速发展使智能交通成为解决交通问题的有效手段.针对交叉口交通流量呈现潮汐性、方向不均衡性的现象,运用交通诱导的思想,提出利用可变进口道解决高峰时段信号交叉口交通拥堵的方法.给出了数据采集的途径和变化车道的条件.采用VMS(可变情报板)及时展示车道变化信息,结合实际,建立交叉口模型,并通过微观交通仿真软件PA-RAMICS丰富的API功能,实现对模型的仿真验证.列出对比评价结果,结果表明进行可变进口道诱导之后,交叉口的服务水平明显提高.
赖元文; 荣建; 刘小明
2012-01-01
In order to estimate the capacity of right-turn lane at signalized intersections with channelized islands. Based on the gap acceptance model, this paper proposes a new approach to calculating the capacity of right-turn lane at signalized intersections with channelized islands. This model takes into account the interference of non-motorized traffic enter channelized islands. The non-motorized traffic is treated as the traffic on the major road-a crosswalk, which has great impacts on right-turn vehicles on the minor road-an exclusive right-turn lane. The basic model is modified by introducing the red light effect adjustment coefficient. The new model is calibrated and tested using the field data collected at 6 signalized intersections with ehannelized islands in 4 cities. The average relative error between the calculated value and the observed is 9.28% , which means the proposed method in this paper can better estimate the capacity of an exclusive free right-turn lane under the interference of non-motorized traffic.%为了计算在信号交叉口设置导流岛后右转车道的通行能力，以接受间隙理论模型为基础，给出了针对设置导流岛的信号交叉口右转车道通行能力计算方法．考虑到非机动车进入导流岛对右转车辆产生较大影响，确定以非机动车流为主路，提出红灯效应修正系数，对基础模型进行修正．通过4个城市6个设置导流岛的信号交叉口实测数据进行模型标定和检验．比较模型计算值与实际观测值发现，平均相对误差为9．28％，表明本文所提计算方法能较好地反映非机动车对右转车道通行能力影响的实际情况．
王龙; 陈京荣
2012-01-01
Supposing that both arrival rata and saturation flow rata of vehicles at signalized intersection are random variables and they are suitable to Poisson distribution, the queue status at the initial time of red light is studied as the object. Theory of queuing systems with sever vacations is applied to establishing delay model for signalized intersection under non-saturated. According to the process of queue formation and dissipation at entrance lane, the formulation is analyzed and divided into addition delay and random delay, then the formulation of intersection delay is obtained. In the end, based on the analysis and comparison of surveyed data and the result of this paper and the result of literature, the conclusion shows that the model result in this paper is closer to the measured data when saturation is between 0. 4 and 0. 6.%假设信号控制交叉口上车辆的到达率和饱和流率均为服从泊松分布的随机变量,以某一相位红灯初始时刻的排队状态为研究对象,运用休假随机服务系统理论,建立了非饱和状态下的信号交叉口延误模型.根据排队形成和消散的过程,把交叉口进口道上的延误分解成附加延误和随机延误两部分,基于延误三角形和生灭过程的思想,得到了附加延误和随机延误的计算公式,并在此基础上给出了信号交叉口进口道上车辆到达率和饱和流率均服从泊松分布时的车辆平均延误计算公式.将计算结果与交通调查数据和已有文献计算结果进行对比,结果表明当饱和度介于0.4与0.6之间时,模型的计算结果更贴近实测数据.
CERN PhotoLab
1974-01-01
The experimental apparatus used at intersection 1 by the CERN-Bologna Collaboration (experiment R105). It consists of two almost identical magnetic spectrometers centered at 90 degrees on opposite sides of the intersection region. In each spectrometer one can see magnetostrictive wire spark chambers, a magnet, more chambers and various hodoscopes of scintillation counters. Gas Cerenkov counters (almost invisible in the picture) are located in the gap of each magnet. On the left hand side, a matrix of 119 lead glass Cerenkov counters is located behind some concrete and iron shielding.
CERN PhotoLab
1971-01-01
Intersection I-1 of the ISR in August 1971 showing the 90 degree large acceptance spectrometer of the Saclay-Strasbourg Collaboration which is studying the momentum spectra of electrons at large angles. On the left of the crossing region can be seen the track used by the CERN-Bucharest-Cracow-Tata Collaboration to bring nuclear emulsions into the ISR.
1971-01-01
Intersection I-2 of the ISR during the installation of experiments. On the left to the crossing region can be seen the massive iron plate structure of the muon detector being used by a British collaboration in a search for the intermediate vector boson. The magnet and hodoscopes on the right are part of the spectrometer arm of the Bristish-Scandinavian Collaration.
Intersectional embodiment and power
Elg, Camilla; Jensen, Sune Qvotrup
Through almost two decades the term ‘intersectionality' has gained influence in post colonial studies, gender studies, feminist theory and other research fields occupied with how social differences are distributed and how individuals are socially constructed in stratified societies. The ‘interse...... differences and discuss the implications this has for our understanding of power relations....
黄伟华
2011-01-01
Traffic congestion has become a hot issue for the major cities.Huancheng South Road is a typical congestion black spots in Kunming city,as it is in the bustling downtown,take what kind of measures to relieve the congestion is particularly critical,building the overpasses,tunnels or choosing other traffic remediation measures.This requires investigation and analysis of existing traffic,and workable remediation plan based on the current problems.In this article,we introduced the whole design process of Kunming Huancheng South Road ＇left-turn-banning＇ remediation project,compared the survey datum before and after the project,and provided a scientific and workable solution for relieve the traffic congestion.%交通拥堵已经成为各大城市面临的热点问题,环城南路是昆明典型的拥堵点,由于其处于繁华的市区,采取何种缓解拥堵的措施显得尤为关键。对现有交通进行调查和分析,针对现有问题,制定出实施性强的整治方案。通过对昆明市环城南路＂禁左＂整治工程设计全过程的介绍,对工程实施前后的调查数据进行比对分析及思考,为缓解交通拥堵提供一种科学合理、操作性强的解决方案。
Extended MRI findings of intersection syndrome
Lee, Roger P.; Hatem, Stephen F.; Recht, Michael P. [Cleveland Clinic, Cleveland, OH (United States)
2009-02-15
The symptoms and physical findings of intersection syndrome have been well described in the clinical medical literature. However, the magnetic resonance imaging (MRI) findings in patients with intersection syndrome of the forearm have only recently been described in a small number of patients. We review our experience with imaging of intersection syndrome, describe previously unreported MRI findings, and emphasize modifications to MRI protocols for its evaluation. Institutional review board approval was obtained for this retrospective review of patients with MRI findings consistent with intersection syndrome of the forearm during the period from January 2004 to September 2006. Six patients were identified, three males and three females, with an average age of 39.3 years. The MRI examinations were reviewed to assess signal abnormalities within and adjacent to the first and second dorsal extensor tendon compartments (DETC): tendinosis, peritendinous edema or fluid, muscle edema, subcutaneous edema, and juxtacortical edema. The overall longitudinal extent of signal alterations was measured as well as the distance from Lister's tubercle to the crossover of the first and second DETC. Review of the MRIs showed increased intrasubstance tendon signal suggesting tendinosis in two of the six patients, peritendinous edema or fluid in all six patients, muscle edema in five of the six patients, and subcutaneous edema in three of the six patients. Juxtacortical edema was seen in one patient. Peritendinous edema or fluid extended distally beyond the radiocarpal joint in three of the six patients. The average distance from Lister's tubercle to the crossover of the first and second DETC was 3.95 cm, in keeping with recently published data. Intersection syndrome is an uncommon MRI diagnosis. In addition to the previously described MRI findings of edema adjacent to the first or second DETC, possibly with proximal extension and subcutaneous edema, we have identified
Improving the Performance of Urban Road Intersection.
Dr. Fareed M.A.Karim
2014-03-01
Full Text Available Road intersection is responsible for an important proportion of air pollution especially in urban areas, due to long queues of vehicles waiting for discharge. Therefore, it is necessary to quantify their emissions as accurately as possible. In this study an attempt was made to research on reducing the traffic air pollution such as CO, CO2, HC and NOx, fuel consumption and vehicle operating cost along with improving the traffic flow and delay at a road intersection. One major uncontrolled (un signalized intersection in capital city Sana'a (Yemen was chosen for the study. The traffic air pollution, fuel consumption and vehicle operating cost as well as vehicle delay was calculated for the base year 2012 using aaSIDRA 2.0 software developed in Australia. For the horizon year 2022, three scenarios were considered for investigation viz. (1 do nothing, (2 signalizing the intersection and (3 construction of flyover. The analysis shows that for the above mentioned parameters scenario (3 will be the best scenario followed by scenario (2, while worst case scenario will be do nothing.
Intersectional embodiment and power
Elg, Camilla; Jensen, Sune Qvotrup
. The ‘intersectional' perspective creates a focus on the coexistence and mutual formation of different kinds of social difference in the construction of the individual social position. The concept of habitus as it was coined by Pierre Bourdieu has been an inspiration for some of this research. However, the focus...... on the embodiment of social dispositions and the social formation of the individual as body inherent in Bourdieu's work have not yet gained weight in this development within ‘difference research'. It might not come to much surprise as the radical sociology of embodiment implicit in the theory of habitus does...... not seem to gain much attention in social stratification research in general. In our paper we will present our work on an embodied approach to intersectionality, which is inspired by Pierre Bourdieu and other thinkers of embodiment. We will argue for the importance of a focus on the embodiment of social...
Chen, C M; Sharakin, S A; Chen, Chiang-Mei; Gal'tsov, Dmitri V.; Sharakin, Sergei A.
1999-01-01
New solution to the six-dimensional vacuum Einstein's equations is constructed as a non-linear superposition of two five-dimensional solutions representing the Melvin-Gibbons-Maeda Universe and its S-dual. Then using duality between D=8 vacuum and a certain class of D=11 supergravity configurations we generate M2 and M5 fluxbranes as well as some of their intersections also including waves and KK-monopoles.
Chandan Keerthi Kancharla
2016-12-01
Full Text Available In isolated intersection’s actuated signal control, inductive loop detector layout plays a crucial role in providingthe vehicle information to the signal controller. Based on vehicle actuations at the detector, the green time is extended till a pre-defined threshold gap-out occurs. The Federal Highway Administration (FHWA proposed various guidelines for detec-tor layouts on low-speed and high-speed approaches. This paper proposes single and multiple advance detection schemes for low-speed traffic movements, that utilizes vehicle actuations from advance detectors located upstream of the stop-line, which are able to detect spill-back queues. The proposed detection schemes operate with actuated signal control based on lane-by-lane gap-out criteria. The performance of the proposed schemes is compared with FHWA’s stop-line and single advance detection schemes in the VISSIM simulation tool. Results have shown that the proposed single advance detection schemes showed improved performance in reducing travel time delay and average number of stops per vehicle under low volumes while the multiple advance detection scheme performed well under high volumes.
鲍怡婷; 周竹萍; 徐永能
2016-01-01
Normally,the right-turning movement of vehicles at signalized intersections is not controlled.Thus, there are potential risks of conflicts between the right-turning vehicles and cross-walking pedestrians.Current studies ad-dressed on the identification and classification of such conflicts,no theoretical model is proposed to analyze such processes of conflicts.With the purpose to reduce conflicts and improve safety of pedestrians,a new simulation model to describe the conflict processes between right-turning vehicles and cross-walking pedestrians is proposed in this study.The decision-making process of right-turning vehicles is studied.Then the mechanism of conflicts between vehicles and pedestrians is analyzed.Finally,a vehicle-pedestrian conflict model is established.Meanwhile,the coefficients for this model are calibra-ted using actual data including vehicle speed and gap acceptance.A simulation study is then conducted to optimize the measurements for safety evaluation:time-to-collision (TTC),post-encroachment time (PET),safety braking decelera-tion,and gap time.The results reveal that PET is the most significant measurement to evaluate vehicle-pedestrian con-flict.The accuracy analysis results show that the deviation of vehicle speed and PET between simulation and actual data is less than 5%,which indicates the validity of this model.An implementation of sensitivity analysis shows that PET of small size intersections increases 10% compared with large size of intersections,which indicates that small intersections have the advantage to reduce the severity of conflicts.%在一些信号交叉口，右转机动车的转弯行为不受信号控制，容易与过街行人发生冲突。现有冲突研究的内容多为冲突判别和冲突分级研究，对人车冲突运动过程研究相对较少。为减少交通冲突，提高行人过街安全性，提出一种新的右转机动车与行人冲突运动过程的仿真模型。研究右转车辆的决策过程，
田宗忠; 马艳; 高鸿雁; 苏洁
2015-01-01
This paper documents the modeling of vehicle delays at signalized intersections with a short right-turn bay which is commonly seen in urban traffic. The model is developed considering the stochastics of traffic volume variation which can result in uncertain blockage occurrences to the short right-turn bay. The proposed model enhances the existing methodologies documented in the U.S. Highway Capacity Manual 2010 (HCM 2010) which treats the short bay as an exclusive full lane. The model incorporates probabilistic theories and intersection characteristics, thus providing an improved approach to delay estimation by considering the short-bay storage length, traffic flow rate, and signal timing. The proposed model is validated using the SimTraffic microscopic simulation model, which is calibrated using field data obtained at a real-world intersection site. Based on the model, it is found that the short-bay length strongly influences the right-turn vehicle delays. In addition, allowing right-turn-on-red (RTOR) can ease the over-saturation problem and reduce the approach delay substantially, especially when the short-bay length is less than 2-vehicle storage length.%研究城市道路中常见的右转短车道信号控制交叉口车辆延误模型.该模型考虑了交通流变化随机性导致的右转短车道交通阻滞问题,改进了现行美国通行能力手册(HCM 2010)中将短车道视为独立进口车道的计算方法.本文应用概率论方法并结合交叉口特性,同时考虑了短车道、交通流率和信号配时等因素影响,提出了一种改进的交叉口延误估计方法.通过使用SimTraffic微观仿真模型,应用交叉口获得的实测数据对模型进行参数标定,验证了模型的有效性.研究结果表明,短车道对右转车辆延误有显著影响.尤其在短车道长度小于2辆标准车长的情况下,允许红灯右转(Righe-turn-on-red, RTOR)可以有效缓解过饱和交通流问题并减少交叉口实际延误.
Silberman, Yuval; Winder, Danny G
2013-01-01
Stress and anxiety play an important role in the development and maintenance of drug and alcohol addiction. The bed nucleus of the stria terminalis (BNST), a brain region involved in the production of long-term stress-related behaviors, plays an important role in animal models of relapse, such as reinstatement to previously extinguished drug-seeking behaviors. While a number of neurotransmitter systems have been suggested to play a role in these behaviors, recent evidence points to the neuropeptide corticotropin releasing factor (CRF) as being critically important in BNST-mediated reinstatement behaviors. Although numerous studies indicate that the BNST is a complex brain region with multiple afferent and efferent systems and a variety of cell types, there has only been limited work to determine how CRF modulates this complex neuronal system at the circuit level. Recent work from our lab and others have begun to unravel these BNST neurocircuits and explore their roles in CRF-related reinstatement behaviors. This review will examine the role of CRF signaling in drug addiction and reinstatement with an emphasis on critical neurocircuitry within the BNST that may offer new insights into treatments for addiction.
Ranking the types of intersections for assessing the safety of pedestrians using TOPSIS method
Călin ŞERBU
2014-11-01
Full Text Available Every year, more than 1500 accidents with pedestrian occur in the intersections in Romania. The number of accidents involving pedestrians in roundabouts intersections type increased approximately three times in 2013 compared to 2009 in Romania. This alarming increase led to the need of assessing the safety of pedestrians in intersections with or without safety systems. The safety systems for pedestrians and drivers include: the road marking, the pedestrian crossings marking, signal intersections with road signs, traffic lights or pedestrian safety barriers. We propose to assess the types of intersections with TOPSIS method.
无
2007-01-01
In this paper, by using the Brunn-Minkowski-Firey mixed volume theory and dual mixed volume theory, associated with Lp intersection body and dual mixed volume, some dual Brunn-Minkowski inequalities and their isolate forms are established for Lp intersection body about the normalized Lp radial addition and Lp radial linear combination. Some properties of operator Lp are given.
INEQUALITIES FOR MIXED INTERSECTION BODIES
YUAN SHUFENG; LENG GANGSONG
2005-01-01
In this paper, some properties of mixed intersection bodies are given, and inequalities from the dual Brunn-Minkowski theory (such as the dual Minkowski inequality, the dual Aleksandrov-Fenchel inequalities and the. dual Brunn-Minkowski inequalities) are established for mixed intersection bodies.
-Mixed Intersection Bodies and Star Duality
Zhao Chang-jian; Wing-Sum Cheung
2010-09-01
The paper extends the two notions of the dual mixed volumes and -intersection body to -dual mixed volumes and -mixed intersection body, respectively. Inequalities for the star dual of -mixed intersection bodies are established.
Intersectional perspective in elderly care
Marta Cuesta
2016-05-01
Full Text Available Earlier research has shown that power relationships at workplaces are constructed by power structures. Processes related to power always influence the working conditions for (in this study in elderly care the working groups involved. Power structures are central for intersectional analysis, in the sense that the intersectional perspective highlights aspects such as gender and ethnicity (subjective dimensions and interrelates them to processes of power (objective dimension. This qualitative study aims to explore in what way an intersectional perspective could contribute to increased knowledge of power structures in a nursing home where the employees were mostly immigrants from different countries. By using reflexive dialogues related to an intersectional perspective, new knowledge which contributes to the employees’ well-being could develop. Narrative analysis was the method used to conduct this study. Through a multi-stage focus group on six occasions over 6 months, the staff were engaged in intersectional and critical reflections about power relationship with the researchers, by identifying patterns in their professional activities that could be connected to their subjectivities (gender, ethnicity, etc.. The result of this study presents three themes that express the staff's experiences and connect these experiences to structural discrimination. 1 Intersectionality, knowledge, and experiences of professionalism; 2 Intersectionality, knowledge, and experiences of collaboration; and 3 Intersectionality, knowledge, and experiences of discrimination. The result demonstrates that an intersectional perspective reinforces the involved abilities, during the conversations, into being clear about, for example, their experiences of discrimination, and consequently developing a better understanding of their professionalism and collaboration. Such deeper reflections became possible through a process of consciousness raising, strengthening the employee
Effects of digital countdown timer on intersection safety and efficiency: A systematic review.
Fu, Chuanyun; Zhang, Yaping; Qi, Weiwei; Cheng, Shaowu
2016-01-01
To investigate the available evidence referring to the effectiveness of digital countdown timers (DCTs) in improving the safety and operational efficiency of signalized intersection. A systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement guidelines. Relevant literature was searched from electronic databases using key terms. Based on study selection and methodological quality assessment, 14 studies were included in the review. Findings of the studies were synthesized in a narrative analysis. Three types of DCT had different effects on intersection safety and operational efficiency. Green signal countdown timers (GSCTs) reduced red light violations, type I dilemma zone distributions, and rear-end collision likelihood but increased crossing after yellow onset and had mixed impacts on type II dilemma zone distributions and intersection capacity. In contrast, red signal countdown timers (RSCTs) increased intersection capacity, although their effectiveness in reducing red light violations dissipated over time. Likewise, continuous countdown timers (CCTs) significantly enhanced intersection capacity but had mixed influences on red light violations and crossing after yellow onset. Due to the limited and inconsistent evidence regarding DCTs' effects on intersection safety and efficiency, it is not sufficient to recommend any type of DCT to be installed at signalized intersections to improve safety and operational efficiency. Nevertheless, it is apparent that both RSCTs and CCTs enhance intersection capacity, though their impacts on intersection safety are unclear. Future studies need to further verify those anticipated safe and operational benefits of DCTs with enriched field observation data.
1972-01-01
Towards the left one sees, on top of ISR beam 1, the front section of the 30-metre-long, small-angle spectrometer from the CERN-Holland-Lancaster-Manchester single-particle production experiment. It consists of two special septum magnets carrying up to 20 kA each. These magnets are necessary to force charged particles produced at small angles away from the ISR beam. They are followed by two threshold Cerenkov counters and (not visible) three more bending magnets and a 6-metre-long Cerenkov counter. Particle identification follows from the Cerenkov signals after determination of the particle trajectory through the spectrometer with magnetostrictive spark chambers. The positions of the first magnets and Cerenkov counters can be changed by remote control. In front one sees the electronics which determines the traversal of a charged particle from scintillator counter signals and gives the "fire" signal for the spark chambers.
Intersectionality in European Union policymaking
Lombardo, Emanuela; Agustin, Lise Rolandsen
2016-01-01
is particularly apt to deal with equality and diversity in policymaking. By analysing a selection of European Union policy documents on gender-based violence in the period 2000–2014, we attend to the question of what intersectionality can bring to policymaking in terms of strengthening inclusiveness and address...
Mitigating gas emissions at signalised intersections using wireless vehicle detectors
Moses Kwasi Torkudzor
2015-09-01
Full Text Available Traffic congestion on roads wastes travel times and increases fuel consumption as well as gas emissions which are dangerous to human health. This has led to growing concern about environmental protection and energy conservation and a number of studies to increase fuel economy and reduce gas emissions. To increase travel times so as to reduce fuel consumption and gas emissions, traffic signals at intersections must be well implemented. It is therefore necessary to employ the current technology of wireless sensor networks to enhance the optimisation of the signalised intersections so as to address such a concern. In this study, a vehicular traffic control model was developed to optimise a signalised intersection, using wireless vehicle detectors. Real-time traffic volume gathered were analysed to obtain the peak hour traffic volume causing congestion. The intersection was modelled and simulated in Synchro7 as an actuated signalised model using results from the analysed data. The model for morning peak and evening peak periods gave optimal cycle lengths which result in the reduction of gas emissions, fuel consumption and delay at the intersection.
MATLAB Simulation of Fuzzy Traffic Controller for Multilane Isolated Intersection
Azura Che Soh/Lai Guan Rhung
2010-07-01
Full Text Available This paper presents a MATLAB simulation of fuzzy traffic controller for controlling traffic flow at multilane isolated signalized intersection. The controller is developed based on the waiting time and vehicles queue length at current green phase, and vehicles queue lengths at the other phases. For control strategy, the controllercontrols the traffic light timings and phase sequence to ensure smooth flow of traffic with minimal waiting time, queue length and delay time. In this research, the isolated intersection model used consists of two lanes in each approach. Each approach has two different values of vehicles queue length and waiting time, respectively, at the intersection. The maximum values of vehicles queue length and waiting times are selected as the inputs to controller for optimized control of traffic flows at the intersection. A traffic model and fuzzy traffic controller are developed to evaluate the performance of traffic controllers underdifferent conditions. In the end, by comparing the experimental result obtained by the vehicle-actuated controller (VAC and fuzzy traffic controller (FTC which improves significant performance for intersections, we confirmed the efficiency of our intelligent controller based fuzzy inference system.
Reconstructing surface triangulations by their intersection matrices
2014-01-01
The intersection matrix of a finite simplicial complex has as each of its entries the rank of the intersection of its respective simplices. We prove that such matrix defines the triangulation of a closed connected surface up to isomorphism.
Using Intersectionality in Student Affairs Research
Strayhorn, Terrell L.
2017-01-01
This chapter presents intersectionality as a useful heuristic for conducting research in higher education and student affairs contexts. Much more than just another theory, intersectionality can powerfully shape student affairs research in both obvious and tacit ways.
The Clique Problem in Ray Intersection Graphs
Cabello, Sergio; Langerman, Stefan
2011-01-01
Ray intersection graphs are intersection graphs of rays, or halflines, in the plane. We show that any planar graph has an even subdivision whose complement is a ray intersection graph. The construction can be done in polynomial time and implies that finding a maximum clique in a segment intersection graph is NP-hard. This solves a 21-year old open problem posed by Kratochv\\'il and Ne\\v{s}et\\v{r}il.
Safety performance models for urban intersections in Brazil.
Barbosa, Heloisa; Cunto, Flávio; Bezerra, Bárbara; Nodari, Christine; Jacques, Maria Alice
2014-09-01
This paper presents a modeling effort for developing safety performance models (SPM) for urban intersections for three major Brazilian cities. The proposed methodology for calibrating SPM has been divided into the following steps: defining the safety study objective, choosing predictive variables and sample size, data acquisition, defining model expression and model parameters and model evaluation. Among the predictive variables explored in the calibration phase were exposure variables (AADT), number of lanes, number of approaches and central median status. SPMs were obtained for three cities: Fortaleza, Belo Horizonte and Brasília. The SPM developed for signalized intersections in Fortaleza and Belo Horizonte had the same structure and the most significant independent variables, which were AADT entering the intersection and number of lanes, and in addition, the coefficient of the best models were in the same range of values. For Brasília, because of the sample size, the signalized and unsignalized intersections were grouped, and the AADT was split in minor and major approaches, which were the most significant variables. This paper also evaluated SPM transferability to other jurisdiction. The SPM for signalized intersections from Fortaleza and Belo Horizonte have been recalibrated (in terms of the Cx) to the city of Porto Alegre. The models were adjusted following the Highway Safety Manual (HSM) calibration procedure and yielded Cx of 0.65 and 2.06 for Fortaleza and Belo Horizonte SPM respectively. This paper showed the experience and future challenges toward the initiatives on development of SPMs in Brazil, that can serve as a guide for other countries that are in the same stage in this subject.
Composite fluxbranes with general intersections
Ivashchuk, V D
2002-01-01
Generalized composite fluxbrane solutions for a wide class of intersection rules are obtained. The solutions are defined on a manifold which contains a product of n Ricci-flat spaces M_1 x ... x M_n with 1-dimensional M_1. They are defined up to a set of functions H_s obeying non-linear differential equations equivalent to Toda-type equations with certain boundary conditions imposed. A conjecture on polynomial structure of governing functions H_s for intersections related to semisimple Lie algebras is suggested. This conjecture is valid for Lie algebras: A_m, C_{m+1}, m > 0. For simple Lie algebras the powers of polynomials coincide with the components of the dual Weyl vector in the basis of simple roots. Explicit formulas for A_1 + ... + A_1 (orthogonal), "block-ortogonal" and A_2 solutions are obtained. Certain examples of solutions in D = 11 and D =10 (II A) supergravities (e.g. with A_2 intersection rules) and Kaluza-Klein dyonic A_2 flux tube, are considered.
MATLAB Simulation of Fuzzy Traffic Controller for Multilane Isolated Intersection
2010-01-01
This paper presents a MATLAB simulation of fuzzy traffic controller for controlling traffic flow at multilane isolated signalized intersection. The controller is developed based on the waiting time and vehicles queue length at current green phase, and vehicles queue lengths at the other phases. For control strategy, the controllercontrols the traffic light timings and phase sequence to ensure smooth flow of traffic with minimal waiting time, queue length and delay time. In this research, the ...
Projective modules and complete intersections
Mandal, Satya
1997-01-01
In these notes on "Projective Modules and Complete Intersections" an account on the recent developments in research on this subject is presented. The author's preference for the technique of Patching isotopic isomorphisms due to Quillen, formalized by Plumsted, over the techniques of elementary matrices is evident here. The treatment of Basic Element theory here incorporates Plumstead's idea of the "generalized dimension functions". These notes are highly selfcontained and should be accessible to any graduate student in commutative algebra or algebraic geometry. They include fully self-contained presentations of the theorems of Ferrand-Szpiro, Cowsik-Nori and the techniques of Lindel.
Rao, B. Jayachander; Gelin, Maxim F.; Domcke, Wolfgang
2017-02-01
We theoretically investigate the feasibility of characterizing conical intersections with time-resolved resonant femtosecond stimulated Raman spectroscopy (FSRS) using an intense actinic pump pulse. We perform nonperturbative numerical simulations of FSRS signals for a three-electronic-state two-vibrational-mode model, which is inspired by the S 2 ( π π * )- S 1 ( n π * ) conical intersection in pyrazine. Our results show that moderately strong actinic pulses increase the intensity of vibrational fingerprint lines in FSRS transients. They facilitate the extraction of useful spectroscopic information by enhancing peaks revealing the coupling and tuning modes of the conical intersection.
Tropical intersection theory on R^n
Flossmann, Simon
2014-01-01
In these notes we survey the tropical intersection theory on R^n by deriving the properties for tropical cycles from the corresponding properties in Chow cohomology. For this we review the stable intersection product introduced by Mikhalkin and the push forward of tropical cycles defined by Allermann and Rau. Furthermore we define a pull back for tropical cycles based on the pull back of Minkowski weights. This pull back commutes with the tropical intersection product and satisfies the projec...
Tropical intersection theory on R^n
Flossmann, Simon
2014-01-01
In these notes we survey the tropical intersection theory on R^n by deriving the properties for tropical cycles from the corresponding properties in Chow cohomology. For this we review the stable intersection product introduced by Mikhalkin and the push forward of tropical cycles defined by Allermann and Rau. Furthermore we define a pull back for tropical cycles based on the pull back of Minkowski weights. This pull back commutes with the tropical intersection product and satisfies the projec...
2008-01-01
In this paper the author first introduce a new concept of Lp-dual mixed volumes of star bodies which extends the classical dual mixed volumes. Moreover, we extend the notions of Lp- intersection body to Lp-mixed intersection body. Inequalities for Lp-dual mixed volumes of Lp-mixed intersection bodies are established and the results established here provide new estimates for these type of inequalities.
The clique problem in ray intersection graphs
Langerman, Stefan; Cardinal, Jean; Cabello, Sergio
2015-01-01
Ray intersection graphs are intersection graphs of rays, or halflines, in the plane. We show that any planar graph has an even subdivision whose complement is a ray intersection graph. The construction can be done in polynomial time and implies that finding a maximum clique in a segment intersection graph is NP-hard. This solves a 21-year old open problem posed by Kratochvíl and Nešetřil (Comment Math Univ Carolinae 31(1):85-93, 1990).
DESIGNING AN EFFECTIVE INTERSECTION USING CAD ENVIRONMENT
CRISAN George-Horea
2017-05-01
Full Text Available Ensuring the safety and streamline in road traffic are very important aims, with regard to the nowadays people mobility level. Road infrastructure is an essential element that can meet these requirements. Thus, it is proposed to develop an effective model of intersection by using CAD software tools. This type of intersection can be successfully used on almost any category of roads, increasing road traffic safety, reducing passing times through the intersection and in the same time, reducing conflict points and increase the intersection capacity.
POLES OF ZETA FUNCTIONS OF COMPLETE INTERSECTIONS
无
2000-01-01
A vanishing theorem is proved for -adic cohomology with compact support on an affine (singular) complete intersection. As an application, it is shown that for an affine complete intersection defined over a finite field of q elements, the reciprocal "poles" of the zeta function are always divisible by q as algebraic integers. A p-adic proof is also given, which leads to further q-divisibility of the poles or equivalently an improvement of the polar part of the AxKatz theorem for an affine complete intersection. Similar results hold for a projective complete intersection.
Vehicular crash data used to rank intersections by injury crash frequency and severity
Yi Liu; Zongzhi Li; Jingxian Liu; Harshingar Patel
2016-01-01
This article contains data on research conducted in “A double standard model for allocating limited emergency medical service vehicle resources ensuring service reliability” (Liu et al., 2016) [1]. The crash counts were sorted out from comprehensive crash records of over one thousand major signalized intersections in the city of Chicago from 2004 to 2010. For each intersection, vehicular crashes were counted by crash severity levels, including fatal, injury Types A, B, and C for major, modera...
Tracks, intersections and dead ends
Siim, Birte; Skjeie, Hege
2008-01-01
of organisations of civil society in political power. The second part explores the framing of the hijab as a political issue of "intersections" of gender equality versus religious belongings. The third part investigates what we see as a "dead end" in policy making to prevent violations of women's rights......The article discusses multicultural challenges to state feminism in Denmark and Norway focusing both on similarities and differences in the two countries policy responses. In spite of important differences, we point towards similar problems and dilemmas in the public responses to multiculturalism......; that is the general, age based, restrictions on family unification as a means to combat forced marriages. Finally, in the conclusion, we emphasise the importance of participatory women-friendly politics that include all who are affected by political decisions. ...
Framing Gender Intersections in the European Union
Lombardo, Emanuela; Agustin, Lise Rolandsen
2012-01-01
This article explores the extent to which the emergence of an antidiscrimination policy in the European Union (EU) implies a shift in EU gender equality policies towards an intersectional approach. The frame analysis of EU gender equality policy documents shows that intersectional dimensions...
Computations in intersection rings of flag bundles
Grayson, Daniel R; Stillman, Michael E
2012-01-01
Intersection rings of flag varieties and of isotropic flag varieties are generated by Chern classes of the tautological bundles modulo the relations coming from multiplicativity of total Chern classes. In this paper we describe the Groebner bases of the ideals of relations and give applications to computation of intersections, as implemented in Macaulay2.
Framing Gender Intersections in the European Union
Lombardo, Emanuela; Agustin, Lise Rolandsen
2012-01-01
This article explores the extent to which the emergence of an antidiscrimination policy in the European Union (EU) implies a shift in EU gender equality policies towards an intersectional approach. The frame analysis of EU gender equality policy documents shows that intersectional dimensions...
An intersection algorithm based on transformation
CHEN Xiao-xia; YONG Jun-hai; CHEN Yu-jian
2006-01-01
How to obtain intersection of curves and surfaces is a fundamental problem in many areas such as computer graphics,CAD/CAM,computer animation,and robotics.Especially,how to deal with singular cases,such as tangency or superposition,is a key problem in obtaining intersection results.A method for solving the intersection problem based on the coordinate transformation is presented.With the Lagrange multiplier method,the minimum distance between the center of a circle and a quadric surface is given as well.Experience shows that the coordinate transformation could significantly simplify the method for calculating intersection to the tangency condition.It can improve the stability of the intersection of given curves and surfaces in singularity cases.The new algorithm is applied in a three dimensional CAD software (GEMS),produced by Tsinghua University.
At the Intersection of Identities
Hidasi Judit
2016-12-01
Full Text Available It is assumed that part of today’s societal difficulties, uncertainties and crisis worldwide can be attributed to the competing of multiple identities, to their intersections and their overlapping nature – on the level of nations, on the level of communities and also on the level of the individual. We aim at presenting a typology of identities that come into play in the public and in the private domain of the individual. It is hypothesized that there is a strong interdependence of cultural heritage, human values and social traditions in the competition of identities. These questions, which are interrelated and interconnected with each other through a common denominator, namely “cultural-mental programming” and “reprogramming efforts,” are going to be pondered about in the presentation. In the context of globalization the relevance of this topic is reinforced by the need to adapt to changes within the ever-intensifying shift from intercultural to multicultural environment in communities, in business and in work places. Attempts will be made to articulate some projections with respect to future trends that are to be expected: the way to go from competing identities to establishing a competitive identity (Simon Anholt. The contribution does not offer ready solutions but rather serves as fuel for further discussions.
Session Types = Intersection Types + Union Types
Padovani, Luca
2011-01-01
We propose a semantically grounded theory of session types which relies on intersection and union types. We argue that intersection and union types are natural candidates for modeling branching points in session types and we show that the resulting theory overcomes some important defects of related behavioral theories. In particular, intersections and unions provide a native solution to the problem of computing joins and meets of session types. Also, the subtyping relation turns out to be a pre-congruence, while this is not always the case in related behavioral theories.
Conical intersections in an ultracold gas
Wüster, S; Rost, J M
2010-01-01
We find that energy surfaces of more than two atoms or molecules interacting via dipole-dipole po- tentials generically possess conical intersections (CIs). Typically only few atoms participate strongly in such an intersection. For the fundamental case, a circular trimer, we show how the CI affects adiabatic excitation transport via electronic decoherence or geometric phase interference. These phe- nomena may be experimentally accessible if the trimer is realized by light alkali atoms in a ring trap, whose dipole-dipole interactions are induced by off-resonant dressing with Rydberg states. Such a setup promises a direct probe of the full many-body density dynamics near a conical intersection.
Optimising Signalised Intersection Using Wireless Vehicle Detectors
Adjin, Daniel Michael Okwabi; Torkudzor, Moses; Asare, Jack
Traffic congestion on roads wastes travel times. In this paper, we developed a vehicular traffic model to optimise a signalised intersection in Accra, using wireless vehicle detectors. Traffic volume gathered was extrapolated to cover 2011 and 2016 and were analysed to obtain the peak hour traffic...... volume causing congestion. The intersection was modelled and simulated in Synchro7 as an actuated signalised model using results from the analysed data. The model for morning peak periods gave optimal cycle lengths of 100s and 150s with corresponding intersection delay of 48.9s and 90.6s in 2011 and 2016...... respectively while that for the evening was 55s giving delay of 14.2s and 16.3s respectively. It is shown that the model will improve traffic flow at the intersection....
Hirzebruch-Milnor classes of complete intersections
Maxim, Laurentiu; Schuermann, Joerg
2012-01-01
We prove a new formula for the Hirzebruch-Milnor classes of global complete intersections with arbitrary singularities describing the difference between the Hirzebruch classes and the virtual ones. This generalizes a formula for the Chern-Milnor classes in the hypersurface case that was conjectured by S. Yokura and was proved by A. Parusinski and P. Pragacz. It also generalizes a formula of T. Suwa for the Chern-Milnor classes of complete intersections with isolated singularities.
CONTROLLING TRAFFIC FLOW IN MULTILANE-ISOLATED INTERSECTION USING ANFIS APPROACH TECHNIQUES
2015-01-01
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 L...
CONTROLLING TRAFFIC FLOW IN MULTILANE-ISOLATED INTERSECTION USING ANFIS APPROACH TECHNIQUES
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.
何兆成; 佘锡伟; 杨文臣; 陈宁宁
2011-01-01
To address the dynamics and uncertainty in unban transportation system, this paper proposed a traffic signal control system based on reinforcement learning, which was suitable for real-time control in isolated intersection.The proposed method was capable of online learning through a combination of BP neural network and Q-learning algorithm.Furthermore, due to the multi-objective property in traffic signal control, this paper developed a reward design method for Q-learning based on fuzzy logic.Conducted simulated experiments in three traffic scenarios, using the Paramics microscopic traffic simulation software.Experimental results show that the proposed method has high control efficiency in different traffic scenarios, and is significantly better than fixed timing control method.%针对城市交通系统的动态性和不确定性,提出了基于强化学习的信号交叉口智能控制系统结构,对单交叉口动态实时控制进行了研究.将BP神经网络与Q学习算法相结合实现了路口的在线学习.同时,针对交通信号控制的多目标评价特征,采用基于模糊逻辑的Q学习奖惩信号设计方法,实施对交通信号的优化控制.最后,在三种交通场景下,应用Paramics微观交通仿真软件对典型十字路口进行仿真实验.结果表明,该方法对不同交通场景下的突变仍可保持较高的控制效率,控制效果明显优于定时控制.
Interactions between Intersecting Pedestrian and Vehicle Flows on Roads
GUO Ren-Yong; GUO Xi
2011-01-01
The crossing of vehicle How by pedestrians at either signalized crosswalks or locations away from crosswalks is studied using a car-following model. The model process is constructed, and two safe criterions deciding whether pedestrians begin to cross a road and a rule stopping vehicles at a signal intersection are proposed. Numerical results indicate that the relations of both vehicles' and pedestrians' delays to the width of pedestrian arrival interval are nonlinear; careful pedestrians unnecessarily spend more time to cross a road than aggressive ones; pedestrians crossing near a traffic signal have more influence on their and vehicles' delays. When pedestrians are permitted to cross a road using the gaps between slow vehicles, their delay may increase.%The crossing of vehicle flow by pedestrians at either signalized crosswalks or locations away from crosswalks is studied using a car-following model.The model process is constructed,and two safe criterions deciding whether pedestrians begin to cross a road and a rule stopping vehicles at a signal intersection are proposed.Numerical results indicate that the relations of both vehicles' and pedestrians' delays to the width of pedestrian arrival interval are nonlinear;careful pedestrians unnecessarily spend more time to cross a road than aggressive ones;pedestrians crossing near a traffic signal have more influence on their and vehicles' delays.When pedestrians are permitted to cross a road using the gaps between slow vehicles,their delay may increase.In recent years,intersecting pedestrian and vehicle flows on roads have been studied by using the microscopic simulation method.[1-5] In the method,the dynamics of vehicle flow are formulated by cell automata (CA) models[5] or car-following (CF) models[1-3] generally.It is well known that space is discretized into cells and the length of cells measures the moving distance of vehicles in the CA models.Thus,the CA models are used to investigate the effects of vehicles
Samia Boubaker
2016-06-01
Full Text Available A vehicle's energy consumption and emissions are two major constraints in sustainable development. Both of them have proportionally raised in recent decades with the exponential growth of world traffic demands. The reduction of road traffic-generated energy consumption and emissions have thus become unprecedentedly challenging and worth examining. This paper investigates energy consumption and environmental problems present at roundabout and signalized intersection to analyze the impact of the hybridization level's fleet and intersection type on vehicle consumption and pollution. Instantaneous fuel consumption and emission models coupled with simulation of urban mobility (SUMO are in this study. The authors started with modeling energy consumption. Then, an emission model emissions from traffic (EMIT was implemented to quantify vehicle emissions of CO2, CO and NOx. These models help investigate the influence of intersection type on energy consumption and environmental conditions. The authors implemented a signalized intersection and roundabout using SUMO. The input data are collected from the roundabout of Sousse (Tunisia using video data collection. Since there is a lack of econometric models that emulate hybridized stream behavior near intersections, two energy consumption models for the roundabout and crossroad are developed using traffic flow and hybridization level as the input variables. Compared to crossroads, a roundabout can obtain more environmental improvements and substantial reductions in energy consumption and road traffic emissions.
Intersection Logic in sequent calculus style
Della Rocca, Simona Ronchi; Stavrinos, Yiorgos; Veneti, Anastasia; 10.4204/EPTCS.45.2
2011-01-01
The intersection type assignment system has been designed directly as deductive system for assigning formulae of the implicative and conjunctive fragment of the intuitionistic logic to terms of lambda-calculus. But its relation with the logic is not standard. Between all the logics that have been proposed as its foundation, we consider ISL, which gives a logical interpretation of the intersection by splitting the intuitionistic conjunction into two connectives, with a local and global behaviour respectively, being the intersection the local one. We think ISL is a logic interesting by itself, and in order to support this claim we give a sequent calculus formulation of it, and we prove that it enjoys the cut elimination property.
Modeling aggressive driver behavior at unsignalized intersections.
Kaysi, Isam A; Abbany, Ali S
2007-07-01
The processing of vehicles at unsignalized intersections is a complex and highly interactive process, whereby each driver makes individual decisions about when, where, and how to complete the required maneuver, subject to his perceptions of distances, velocities, and own car's performance. Typically, the performance of priority-unsignalized intersections has been modeled with probabilistic approaches that consider the distribution of gaps in the major-traffic stream and their acceptance by the drivers of minor street vehicles based on the driver's "critical gap". This paper investigates the aggressive behavior of minor street vehicles at intersections that are priority-unsignalized but operate with little respect of control measures. The objective is to formulate a behavioral model that predicts the probability that a driver performs an aggressive maneuver as a function of a set of driver and traffic attributes. Parameters that were tested and modeled include driver characteristics (gender and age), car characteristics (performance and model year), and traffic attributes (number of rejected gaps, total waiting time at head of queue, and major-traffic speed). Binary probit models are developed and tested, based on a collected data set from an unsignalized intersection in the city of Beirut, to determine which of the studied variables are statistically significant in determining the aggressiveness of a specific driver. Primary conclusions reveal that age, car performance, and average speed on the major road are the major determinants of aggressive behavior. Another striking conclusion is that the total waiting time of the driver while waiting for an acceptable gap is of little significance in incurring the "forcing" behavior. The obtained model is incorporated in a simple simulation framework that reflects driver behavior and traffic stream interactions in estimating delay and conflict measures at unsignalized intersections. The simulation results were then compared
Simulation of intersecting black brane solutions
Ivashchuk, V D; Selivanov, A B
2003-01-01
A family of spherically symmetric solutions with horizon in the model with multi-component anisotropic fluid (MCAF) is obtained. The metric of any solution contains n-1 Ricci-flat ``internal space'' metrics and for certain equations of state (p_i = \\pm \\rho) coincides with the metric of intersecting black brane solution in the model with antisymmetric forms. Examples of simulation of intersecting M2 and M5 black branes are considered. The post-Newtonian parameters beta and gamma corresponding to the 4-dimensional section of the metric are calculated.
Switching exciton pulses through conical intersections
Leonhardt, K; Rost, J -M
2013-01-01
Exciton pulses transport excitation and entanglement adiabatically through Rydberg aggregates, assemblies of highly excited light atoms, which are set into directed motion by resonant dipole-dipole interaction. Here, we demonstrate the coherent splitting of such pulses as well as the spatial segregation of electronic excitation and atomic motion. Both mechanisms exploit local non-adiabatic effects at a conical intersection, turning them from a decoherence source into an asset. The intersection provides a sensitive knob controlling the propagation direction and coherence properties of exciton pulses.
Coe, Joshua D [Los Alamos National Laboratory; Levine, B G [U IL AT URBANA-CHAMPAIGN; Ong, M T [UIUC; Martinez, T J [UIUC
2008-01-01
We discuss the connectivity of intersection spaces and the role of minimal energy points within these intersection spaces (minimal energy conical intersections or MECIs) in promoting nonadiabatic transitions. We focus on malonaldeyde as a specific example, where there is a low-lying three-state conical intersection. This three-state intersection is the global minimum on the bright excited electronic state, but it plays a limited role in population transfer in our ab initio multiple spawning (AIMS) simulations because the molecule must traverse a series of two-state conical intersections to reach the three-state intersection. Due to the differences in seam space dimensionality separating conventional (two-state) and three-state intersections, we suggest that dynamical effects arising directly from a three-state intersection may prove difficult to observe in general. We also use a newly developed method for intersection optimization with geometric constraints to demonstrate the connectivity of all the stationary points in the intersection spaces for malonaldehyde. This supports the conjecture that all intersection spaces are connected, and that three-state intersections play a key role in extending this connectivity to all pairs of states, e.g. the S{sub 1}/S{sub 0} and S{sub 2}/S{sub 1} intersection spaces.
Traffic data for local emissions monitoring at a signalized intersection
Bigazzi, A.; Lint, J.W.C. van; Klunder, G.; Stelwagen, U.; Ligterink, N.E.
2010-01-01
In order to assist planning efforts for air pollution-responsive dynamic traffic management (DTM) systems, this research assesses the accuracy of local emissions monitoring based on traffic data and models. The study quantifies the benefits of increased data resolution for short-term emissions estim
Intersection layout, traffic volumes and accidents.
Poppe, F.
1988-01-01
This paper reports on the accident research carried out as a part of a large project started in 1983. For this accident research an inventory was made of a large number of intersections.Recorded were layout features, accident data and estimates of traffic volumes. Attention will be given to the
The landscape of intersecting brane models
Douglas, M R; Douglas, Michael R.; Taylor, Washington
2007-01-01
We develop tools for analyzing the space of intersecting brane models. We apply these tools to a particular $T^6/Z^2_2$ orientifold which has been used for model building. We prove that there are a finite number of intersecting brane models on this orientifold which satisfy the Diophantine equations coming from supersymmetry. We give estimates for numbers of models with specific gauge groups, which we confirm numerically. We analyze the distributions and correlations of intersection numbers which characterize the numbers of generations of chiral fermions, and show that intersection numbers are roughly independent, with a characteristic distribution which is peaked around 0 and in which integers with fewer divisors are mildly suppressed. As an application, the number of models containing a gauge group $SU(3) \\times SU(2) \\times U(1)$ or $SU(4) \\times SU(2) \\times SU(2)$ and 3 generations of appropriate types of chiral matter is estimated to be order ${\\cal O} (10)$, in accord with previous explicit constructio...
Intersection of the Exponential and Logarithmic Curves
Boukas, Andreas; Valahas, Theodoros
2009-01-01
The study of the number of intersection points of y = a[superscript x] and y = log[subscript a]x can be an interesting topic to present in a single-variable calculus class. In this article, the authors present a classroom presentation outline involving the basic algebra and the elementary calculus of the exponential and logarithmic functions. The…
The Priority of Intersectionality in Academic Medicine.
Eckstrand, Kristen L; Eliason, Jennifer; St Cloud, Tiffani; Potter, Jennifer
2016-07-01
Recent societal events highlight inequities experienced by underrepresented and marginalized communities. These inequities are the impetus for ongoing efforts in academic medicine to create inclusive educational and patient care environments for diverse stakeholders. Frequently, approaches focus on singular populations or broad macroscopic concepts and do not always elucidate the complexities that arise at the intersection between multiple identities and life experiences. Intersectionality acknowledges multidimensional aspects of identity inclusive of historical, structural, and cultural factors. Understanding how multiple identity experiences impact different individuals, from patients to trainees to providers, is critical for improving health care education and delivery. Building on existing work within academic medicine, this Commentary outlines six key recommendations to advance intersectionality in academic medicine: embrace personal and collective loci of responsibility; examine and rectify unbalanced power dynamics; celebrate visibility and intersectional innovation; engage all stakeholders in the process of change; select and analyze meaningful metrics; and sustain the commitment to achieving health equity over time. Members of the academic medical community committed to advancing health equity can use these recommendations to promote and maintain meaningful changes that recognize and respond to the multidimensional voices and expressed needs of all individuals engaged in providing and receiving health care.
A Finite Model Property for Intersection Types
Rick Statman
2015-03-01
Full Text Available We show that the relational theory of intersection types known as BCD has the finite model property; that is, BCD is complete for its finite models. Our proof uses rewriting techniques which have as an immediate by-product the polynomial time decidability of the preorder <= (although this also follows from the so called beta soundness of BCD.
Grindr Culture: Intersectional and Socio-Sexual
Shield, Andrew DJ
2017-01-01
and gender, (dis)ability and other socio-cultural categories intersect with users’ (homo)sexual identities while navigating the online subculture. The results and discussion sections integrate observations about Grindr culture ‘from below’ – such as the discourses circulated by Grindr’s users...
30 CFR 56.7055 - Intersecting holes.
2010-07-01
... Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7055 Intersecting holes. Holes shall not be drilled where there is a danger...
30 CFR 57.7055 - Intersecting holes.
2010-07-01
... Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling-Surface and Underground § 57.7055 Intersecting holes. Holes shall not be...
Creating seamless connections: Intersecting the social and ...
Intersecting the social and academic lives of students ... organised by the Centre for Student Support Services at the University of the Western ... benefits of improved performance in classrooms enhanced by this form of collaboration. ... university located in a big city is to create a “small college” life within a larger community.
Intersection numbers with Witten's top Chern class
Shadrin, S.; Zvonkine, D.
2008-01-01
Witten’s top Chern class is a particular cohomology class on the moduli space of Riemann surfaces endowed with r-spin structures. It plays a key role in Witten’s conjecture relating to the intersection theory on these moduli spaces. Our first goal is to compute the integral of Witten’s class over th
Teaching Science from Cultural Points of Intersection
Grimberg, Bruna Irene; Gummer, Edith
2013-01-01
This study focuses on a professional development program for science teachers near or on American Indian reservations in Montana. This program was framed by culturally relevant pedagogy premises and was characterized by instructional strategies and content foci resulting from the intersection between three cultures: tribal, science teaching, and…
Inauguration ceremony for the Intersecting Storage Rings
1971-01-01
The inauguration ceremony for the Intersecting Storage Rings (ISR) was held on 16 October 1971. Kjell Johnsen is seen in the picture handing a symbolic key to the ISR to Edoardo Amaldi. From left to right on the podium: Victor Frederik Weisskopf, former Director-General; M Antonioz; Willibald Jentschke as Director-General of CERN, and on the other side Werner Heisenberg.
Triangle-intersecting families on eight vertices
Filmus, Yuval
2011-01-01
Simonovits and S\\'{o}s conjectured that the maximal size of a triangle-intersecting family of graphs on $n$ vertices is $2^{\\binom{n}{2}-3}$. Their conjecture has recently been proved using spectral methods. We provide an elementary proof of the special case of $8$ vertices using a partition argument.
Edge Effects in Line Intersect Sampling With
David L. R. Affleck; Timothy G. Gregoire; Harry T. Valentine
2005-01-01
Transects consisting of multiple, connected segments with a prescribed configuration are commonly used in ecological applications of line intersect sampling. The transect configuration has implications for the probability with which population elements are selected and for how the selection probabilities can be modified by the boundary of the tract being sampled. As...
First interactions from the Intersecting Storage Rings
1971-01-01
On 27 January 1971, Kjell Johnsen, who led the construction team which built the Intersecting Storage Rings (ISR), announced that the first ever interactions from colliding protons had been recorded. On the left are Franco Bonaudi, who was responsible for the civil engineering and Dirk Neet, who later took charge of ISR operations.
Vacuum chamber at intersection I-6
1971-01-01
The vacuum chamber at intersection region I-6, one of these where experiments in colliding-beam physics will be taking place. The "wheels" prevent the thin wall (1.5 mm) of the chamber from collapsing. The chamber is equipped with heating tapes and its wrapped in thermal insulation. Residual gas pressure at this and other similar regions is around 10_11.
Vehicular crash data used to rank intersections by injury crash frequency and severity.
Liu, Yi; Li, Zongzhi; Liu, Jingxian; Patel, Harshingar
2016-09-01
This article contains data on research conducted in "A double standard model for allocating limited emergency medical service vehicle resources ensuring service reliability" (Liu et al., 2016) [1]. The crash counts were sorted out from comprehensive crash records of over one thousand major signalized intersections in the city of Chicago from 2004 to 2010. For each intersection, vehicular crashes were counted by crash severity levels, including fatal, injury Types A, B, and C for major, moderate, and minor injury levels, property damage only (PDO), and unknown. The crash data was further used to rank intersections by equivalent injury crash frequency. The top 200 intersections with the highest number of crash occurrences identified based on crash frequency- and severity-based scenarios are shared in this brief. The provided data would be a valuable source for research in urban traffic safety analysis and could also be utilized to examine the effectiveness of traffic safety improvement planning and programming, intersection design enhancement, incident and emergency management, and law enforcement strategies.
Vehicular crash data used to rank intersections by injury crash frequency and severity
Yi Liu
2016-09-01
Full Text Available This article contains data on research conducted in “A double standard model for allocating limited emergency medical service vehicle resources ensuring service reliability” (Liu et al., 2016 [1]. The crash counts were sorted out from comprehensive crash records of over one thousand major signalized intersections in the city of Chicago from 2004 to 2010. For each intersection, vehicular crashes were counted by crash severity levels, including fatal, injury Types A, B, and C for major, moderate, and minor injury levels, property damage only (PDO, and unknown. The crash data was further used to rank intersections by equivalent injury crash frequency. The top 200 intersections with the highest number of crash occurrences identified based on crash frequency- and severity-based scenarios are shared in this brief. The provided data would be a valuable source for research in urban traffic safety analysis and could also be utilized to examine the effectiveness of traffic safety improvement planning and programming, intersection design enhancement, incident and emergency management, and law enforcement strategies.
Intersectionality as a Framework for Inclusive Environments
Nunez, A. M.
2016-12-01
To create more inclusive environments for the advancement of scientific inquiry, it is critical to consider the role of intersectionality. Originating in activism and legal scholarship grounded in the realities of women of color, the concept of intersectionality emphasizes how societal power dynamics shape the differential construction of life opportunities of diverse demographic groups across a variety of social identities, contexts, and historical conditions. Importantly, intersectionality also recognizes that individuals can simultaneously hold privileged and marginalized identities. For example, while white women scientists are less represented in leadership and decision-making positions than their male counterparts, but they typically do not experience the marginalization of being mistaken for cleaning staff at their institutions, as many African American and Latina scientists report. Thus, white women are relatively privileged in this context. This case and national survey data demonstrate the critical importance of recognizing that the intersection of racial and gender identities creates complex and multi-faceted challenges for diverse women scientists in navigating the organizational culture of science. Educational research indicates that interventions seeking to create more inclusivity in science should take into account the relationships between various social identities, contexts, and broader historical conditions that affect the advancement of historically underrepresented minority groups. Therefore, this presentation will provide a conceptual framework of intersectionality to guide interventions to encourage all scientists to recognize the distinctive intellectual and social contributions of those from diverse gender, race, class, disability, sexual orientation, and other identity backgrounds. It will also address how this framework can be applied to develop programs, policies, and practices that transform organizational cultures to be more inclusive
Feuerbacher, Sven; Sommerfeld, Thomas; Cederbaum, Lorenz S
2004-02-15
Whereas conical intersections between potential energy surfaces of bound states are well known, the interaction of short-lived states has been investigated only rarely. Here, we present several systematically constructed model Hamiltonians to study the topology of intersecting complex potential energy surfaces describing short-lived states: We find the general phenomenon of doubly intersecting complex energy surfaces, i.e., there are two points instead of one as in the case of bound states where the potential energy surfaces coalesce. In addition, seams of intersections of the respective real and imaginary parts of the potential energy surfaces emanate from these two points. Using the Sigma* and Pi* resonance states of the chloroethene anion as a practical example, we demonstrate that our complete linear model Hamiltonian is able to reproduce all phenomena found in explicitly calculated ab initio complex potential energy surfaces.
Periodic points in the intersection of immediate attracting basins boundaries
Rossetti, Bastien
2014-01-01
We give sufficient conditions under which the set of eventually periodic points in the intersection of immediate attracting basins boundaries is non-empty. We give other conditions under which this set is dense in the intersection.
Intersections and Unions of Session Types
Coşku Acay
2017-02-01
Full Text Available Prior work has extended the deep, logical connection between the linear sequent calculus and session-typed message-passing concurrent computation with equi-recursive types and a natural notion of subtyping. In this paper, we extend this further by intersection and union types in order to express multiple behavioral properties of processes in a single type. We prove session fidelity and absence of deadlock and illustrate the expressive power of our system with some simple examples. We observe that we can represent internal and external choice by intersection and union, respectively, which was previously suggested by Padovani for a different language of session types motivated by operational rather than logical concerns.
Birationally rigid Fano complete intersections. II
Pukhlikov, Aleksandr
2011-01-01
We prove that a generic (in the sense of Zariski topology) Fano complete intersection $V$ of the type $(d_1,...,d_k)$ in ${\\mathbb P}^{M+k}$, where $d_1+...+d_k=M+k$, is birationally superrigid if $M\\geq 7$, $M\\geq k+3$ and $\\mathop{\\rm max} \\{d_i\\}\\geq 4$. In particular, on the variety $V$ there is exactly one structure of a Mori fibre space (or a rationally connected fibre space), the groups of birational and biregular self-maps coincide, $\\mathop{\\rm Bir} V= \\mathop{\\rm Aut} V$, and the variety $V$ is non-rational. This fact covers a considerably larger range of complete intersections than the result of [J. reine angew. Math. {\\bf 541} (2001), 55-79], which required the condition $M\\geq 2k+1$. The paper is dedicated to the memory of Eckart Viehweg.
Planning of Autonomous Multi-agent Intersection
Viksnin Ilya I.
2016-01-01
Full Text Available In this paper, we propose a traffic management system with agents acting on behalf autonomous vehicle at the crossroads. Alternatively to existing solutions based on usage of semiautonomous control systems with the control unit, proposed in this paper algorithm apply the principles of decentralized multi-agent control. Agents during their collaboration generate intersection plan and determinate the optimal order of road intersection for a given criterion based on the exchange of information about them and their environment. The paper contains optimization criteria for possible routes selection and experiments that perform in order to estimate the proposed model. Experiment results show that this model can significantly reduce traffic density compared to the traditional traffic management systems. Moreover, the proposed algorithm efficiency increases with road traffic density. Furthermore, the availability of control unit in the system significantly reduces the negative impact of possible failures and hacker attacks.
Spiked Instantons from Intersecting D-branes
Nekrasov, Nikita
2016-01-01
The moduli space of spiked instantons that arises in the context of the BPS/CFT correspondence is realised as the moduli space of classical vacua, i.e. low-energy open string field configurations, of a certain stack of intersecting D1-branes and D5-branes in Type IIB string theory. The presence of a constant B-field induces an interesting dynamics involving the tachyon condensation.
Spiked instantons from intersecting D-branes
Nikita Nekrasov
2017-01-01
Full Text Available The moduli space of spiked instantons that arises in the context of the BPS/CFT correspondence [22] is realised as the moduli space of classical vacua, i.e. low-energy open string field configurations, of a certain stack of intersecting D1-branes and D5-branes in Type IIB string theory. The presence of a constant B-field induces an interesting dynamics involving the tachyon condensation.
Gender Equality, Intersectionality and Diversity in Europe
Agustin, Lise Rolandsen
Analyzing the developments which have characterized EU gender equality policies and women's transnational activism since the introduction of multiple discrimination policies in the 1990s, this book identifies two interrelated challenges: diversity of women's interests, and degendering of policies....... Drawing on discursive policy analysis, it addresses the interaction between policies, institutions and civil society actors in relation to gender equality, diversity and intersectionality at the European level. Rolandsen Agustín successfully integrates the concepts of diversity and gender equality...
Spiked instantons from intersecting D-branes
Nekrasov, Nikita; Prabhakar, Naveen S.
2017-01-01
The moduli space of spiked instantons that arises in the context of the BPS/CFT correspondence [22] is realised as the moduli space of classical vacua, i.e. low-energy open string field configurations, of a certain stack of intersecting D1-branes and D5-branes in Type IIB string theory. The presence of a constant B-field induces an interesting dynamics involving the tachyon condensation.
Complete Intersection Fibers in F-Theory
Braun, Volker; Keitel, Jan
2014-01-01
Global F-theory compactifications whose fibers are realized as complete intersections form a richer set of models than just hypersurfaces. The detailed study of the physics associated with such geometries depends crucially on being able to put the elliptic fiber into Weierstrass form. While such a transformation is always guaranteed to exist, its explicit form is only known in a few special cases. We present a general algorithm for computing the Weierstrass form of elliptic curves defined as complete intersections of different codimensions and use it to solve all cases of complete intersections of two equations in an ambient toric variety. Using this result, we determine the toric Mordell-Weil groups of all 3134 nef partitions obtained from the 4319 three-dimensional reflexive polytopes and find new groups that do not exist for toric hypersurfaces. As an application, we construct several models that cannot be realized as toric hypersurfaces, such as the first toric SU(5) GUT model in the literature with disti...
Complete intersection fibers in F-theory
Braun, Volker [Mathematical Institute, University of Oxford,24-29 St Giles’, Oxford, OX1 3LB (United Kingdom); Grimm, Thomas W.; Keitel, Jan [Max-Planck-Institut für Physik,Föhringer Ring 6, 80805 Munich (Germany)
2015-03-24
Global F-theory compactifications whose fibers are realized as complete intersections form a richer set of models than just hypersurfaces. The detailed study of the physics associated with such geometries depends crucially on being able to put the elliptic fiber into Weierstrass form. While such a transformation is always guaranteed to exist, its explicit form is only known in a few special cases. We present a general algorithm for computing the Weierstrass form of elliptic curves defined as complete intersections of different codimensions and use it to solve all cases of complete intersections of two equations in an ambient toric variety. Using this result, we determine the toric Mordell-Weil groups of all 3134 nef partitions obtained from the 4319 three-dimensional reflexive polytopes and find new groups that do not exist for toric hypersurfaces. As an application, we construct several models that cannot be realized as toric hypersurfaces, such as the first toric SU(5) GUT model in the literature with distinctly charged 10 representations and an F-theory model with discrete gauge group ℤ{sub 4} whose dual fiber has a Mordell-Weil group with ℤ{sub 4} torsion.
Vu, Cung Khac; Skelt, Christopher; Nihei, Kurt; Johnson, Paul A.; Guyer, Robert; Ten Cate, James A.; Le Bas, Pierre -Yves; Larmat, Carene S.
2015-08-18
A method of interrogating a formation includes generating a conical acoustic signal, at a first frequency--a second conical acoustic signal at a second frequency each in the between approximately 500 Hz and 500 kHz such that the signals intersect in a desired intersection volume outside the borehole. The method further includes receiving, a difference signal returning to the borehole resulting from a non-linear mixing of the signals in a mixing zone within the intersection volume.
Vu, Cung Khac; Skelt, Christopher; Nihei, Kurt; Johnson, Paul A.; Guyer, Robert; Ten Cate, James A.; Le Bas, Pierre -Yves; Larmat, Carene S.
2015-08-18
A method of interrogating a formation includes generating a conical acoustic signal, at a first frequency--a second conical acoustic signal at a second frequency each in the between approximately 500 Hz and 500 kHz such that the signals intersect in a desired intersection volume outside the borehole. The method further includes receiving, a difference signal returning to the borehole resulting from a non-linear mixing of the signals in a mixing zone within the intersection volume.
Distributed traffic signal control using fuzzy logic
Chiu, Stephen
1992-01-01
We present a distributed approach to traffic signal control, where the signal timing parameters at a given intersection are adjusted as functions of the local traffic condition and of the signal timing parameters at adjacent intersections. Thus, the signal timing parameters evolve dynamically using only local information to improve traffic flow. This distributed approach provides for a fault-tolerant, highly responsive traffic management system. The signal timing at an intersection is defined by three parameters: cycle time, phase split, and offset. We use fuzzy decision rules to adjust these three parameters based only on local information. The amount of change in the timing parameters during each cycle is limited to a small fraction of the current parameters to ensure smooth transition. We show the effectiveness of this method through simulation of the traffic flow in a network of controlled intersections.
Control and optimization for intelligent transportation systems in vicinity of intersections
Liu, Bing
2016-01-01
This thesis is devoted to study the potential applications of autonomous vehicles and V2X communications to construct the intelligent transportation systems. Firstly, the behavior of platoon in connected vehicle environment is studied. A platoon control algorithm is designed to obtain safe spacing as well as accordance of velocity and acceleration for vehicles in the same lane. Secondly, in larger scale, the platoons around an intersection are considered. The throughput in a traffic signal pe...
Reactive chemical dynamics through conical intersections
S Ghosal; B Jayachander Rao; S Mahapatra
2007-09-01
Reaction dynamics of prototypical, D + H2 and Cl (2P) + H2, chemical reactions occurring through the conical intersections of the respective coupled multi-sheeted potential energy surfaces is examined here. In addition to the electronic coupling, nonadiabatic effects due to relativistic spin-orbit coupling are also considered for the latter reaction. A time-dependent wave packet propagation approach is undertaken and the quantum dynamical observables viz., energy resolved reaction probabilities, integral reaction cross-sections and thermal rate constants are reported.
Bicone vacuum chamber for ISR intersection
1975-01-01
This is one of the bicone chambers made of titanium for experiment R 702. The central corrugated part had a very thin titanium wall (0.28 mm). The first of these chambers collapsed in its central part when baked at 300 C (August 1975). After an intensive effort to develop better quality and reproducible welds for this special material, the ISR workshop was able to build two new chambers of this type. One of them was installed at I 7 for R 702 in 1976 and worked perfectly. It was at that time the most "transparent" intersection vacuum chamber. See also 7609219, 7609221.
An Optimal Online Algorithm for Halfplane Intersection
WU Jigang; JI Yongchang; CHEN Guoliang
2000-01-01
The intersection of N halfplanes is a basic problem in computational geometry and computer graphics. The optimal offiine algorithm for this problem runs in time O(N log N). In this paper, an optimal online algorithm which runs also in time O(N log N) for this problem is presented. The main idea of the algorithm is to give a new definition for the left side of a given line, to assign the order for the points of a convex polygon, and then to use binary search method in an ordered vertex set. The data structure used in the algorithm is no more complex than array.
Minimal free resolutions over complete intersections
Eisenbud, David
2016-01-01
This book introduces a theory of higher matrix factorizations for regular sequences and uses it to describe the minimal free resolutions of high syzygy modules over complete intersections. Such resolutions have attracted attention ever since the elegant construction of the minimal free resolution of the residue field by Tate in 1957. The theory extends the theory of matrix factorizations of a non-zero divisor, initiated by Eisenbud in 1980, which yields a description of the eventual structure of minimal free resolutions over a hypersurface ring. Matrix factorizations have had many other uses in a wide range of mathematical fields, from singularity theory to mathematical physics.
Charting Relations between Intersectionality Theory and the Neurodiversity Paradigm
Lauren Rose Strand
2017-06-01
Full Text Available This essay explores central elements and applications of intersectionality theory and the neurodiversity paradigm. First, the histories and tenets of intersectionality theory and neurodiversity paradigm are provided. Then, areas are explored where each of the two approaches might further engage with the principles of the other. Finally, the essay concludes by broadly considering the efforts made by the Black Lives Matter movement and the Autistic Self Advocacy Network to bring attention to and end police violence as both networks employ and attend to elements of intersectionality and neurodiversity. The way these two networks draw on both intersectionality and neurodiversity to further their mission could be a possible site for scholars to consider in the interest of advancing dialogues between intersectionality theory and the neurodiversity paradigm. Ultimately, the essay calls for a continued exploration of the potentials for intersectionality and neurodiversity to complement and complicate one another, both in terms of theoretical development and coalition building.
Aircraft recognition based on the discrepancy of polygon intersection area
Deng, Xiujian; Wang, Yanfang; Feng, Qi
2017-01-01
In this paper, a new algorithm that based on discrepancy of polygon intersection area for aircraft recognition is presented. The recognition algorithm process involves three parts: generating polygon of aircraft, placing overlapping plane polygons and computing the area of total intersecting polygons. For the purpose of getting the polygon of aircraft, the picture that was ready to be recognized has gone through a series of pre-processing and the smallest circumference polygon algorithm was used to get approximate polygon of the target contour. To make the two compared polygons have the approximate area, the similar principle was utilized. The matching procedure was divided into four steps including computing intersecting points, computing polygon intersecting sets, computing the intersecting area and getting the intersecting rate to recognize the aircraft. The data structure of algorithm is based on doubly liked list principle. A mass of simulations illustrate that the proposed algorithm is effective and reasonable.
Surface/Surface Intersection Using Simulated Annealing Genetic Algorithm
无
2000-01-01
The genetic algorithm and marching method are integrated into a novel algorithm to solve the surface intersection problem. By combining genetic algorithm with local searching method the efficiency of evolution is greatly improved. By fully utilizing the global searching ability and instinct attribute for parallel computation of genetic algorithm and the local rapid convergency of marching method, the algorithm can compute the intersection robustly and generate correct topology of intersection curves. The details of the new algorithm are discussed here.
Landscaping of highway medians and roadway safety at unsignalized intersections.
Chen, Hongyun; Fabregas, Aldo; Lin, Pei-Sung
2016-05-01
Well-planted and maintained landscaping can help reduce driving stress, provide better visual quality, and decrease over speeding, thus improving roadway safety. Florida Department of Transportation (FDOT) Standard Index (SI-546) is one of the more demanding standards in the U.S. for landscaping design criteria at highway medians near intersections. The purposes of this study were to (1) empirically evaluate the safety results of SI-546 at unsignalized intersections and (2) quantify the impacts of geometrics, traffic, and landscaping design features on total crashes and injury plus fatal crashes. The studied unsignalized intersections were divided into (1) those without median trees near intersections, (2) those with median trees near intersections that were compliant with SI-546, and (3) those with median trees near intersections that were non-compliant with SI-546. A total of 72 intersections were selected, for which five-year crash data from 2006-2010 were collected. The sites that were compliant with SI-546 showed the best safety performance in terms of the lowest crash counts and crash rates. Four crash predictive models-two for total crashes and two for injury crashes-were developed. The results indicated that improperly planted and maintained median trees near highway intersections can increase the total number of crashes and injury plus fatal crashes at a 90% confidence level; no significant difference could be found in crash rates between sites that were compliant with SI-546 and sites without trees. All other conditions remaining the same, an intersection with trees that was not compliant with SI-546 had 63% more crashes and almost doubled injury plus fatal crashes than those at intersections without trees. The study indicates that appropriate landscaping in highway medians near intersections can be an engineering technology that not only improves roadway environmental quality but also maintains intersection safety.
Intersecting Solitons, Amoeba and Tropical Geometry
Fujimori, Toshiaki; Ohta, Kazutoshi; Sakai, Norisuke; Yamazaki, Masahito
2008-01-01
We study generic intersection (or web) of vortices with instantons inside, which is a 1/4 BPS state in the Higgs phase of five-dimensional N=1 supersymmetric U(Nc) gauge theory on R_t \\times (C^\\ast)^2 \\simeq R^{2,1} \\times T^2 with Nf=Nc Higgs scalars in the fundamental representation. In the case of the Abelian-Higgs model (Nf=Nc=1), the intersecting vortex sheets can be beautifully understood in a mathematical framework of amoeba and tropical geometry, and we propose a dictionary relating solitons and gauge theory to amoeba and tropical geometry. A projective shape of vortex sheets is described by the amoeba. Vortex charge density is uniformly distributed among vortex sheets, and negative contribution to instanton charge density is understood as the complex Monge-Ampere measure with respect to a plurisubharmonic function on (C^\\ast)^2. The Wilson loops in T^2 are related with derivatives of the Ronkin function. The general form of the Kahler potential and the asymptotic metric of the moduli space of a vort...
Locating conical intersections relevant to photochemical reactions
Dick, Bernhard [Institut fuer Physikalische und Theoretische Chemie, Universitaet Regensburg, D 93040 Regensburg (Germany)], E-mail: Bernhard.Dick@chemie.uni-regensburg.de; Haas, Yehuda; Zilberg, Shmuel [Department of Physical Chemistry and the Farkas Center for Light-induced Processes, The Hebrew University of Jerusalem, Jerusalem 91904 (Israel)
2008-05-23
A new computerized method for locating conical intersections of interest in photochemistry is presented. The search is based on the Longuet-Higgins phase change theorem (Berry phase) which provides the subspace required for the initial search. The subspace is approximated as a plane containing three stable structures lying on a Longuet-Higgins loop. The search is conducted for a minimum of {delta}E, the energy difference between two electronic states. It is started using up to three points within the circle defined by the three structures; symmetry, if relevant, is helpful but not essential. Since a two-dimensional subspace of the large 3N - 6 space is used, the search that uses either Cartesian or internal coordinates is efficient and yields a degeneracy after a few iterations. Given that not all degrees of freedom are included in the search, usually a high lying part of the conical intersection is initially located. The system is subsequently optimized along all coordinates keeping {delta}E as close to zero as desired. The method is demonstrated for the symmetric H{sub 3} system and also for the butadiene-cyclobutene-bicyclobutane system in which the three stable structures are not equivalent. The method is general and can be extended to any photochemical system.
Volume of intersection of two cones
Balogun, F A; Cesareo, R
2000-01-01
Radiation measurements utilising collimated source and detector systems invariably result in a target volume described by the overlap of their fields of view. When these collimators are cylindrical, this is derived from the volume of intersection of two cones. In general, analysis of this volume does not lend itself to a direct analytical process. Here, numerical methods of estimating the common volume of two intersecting right cones are presented. These include methods which employ, (a) a sequential scanning of an elemental volume with a predetermined size across a defined space containing the volume of interest and (b) a Monte Carlo technique. The accuracy obtainable and the execution time in the first type of algorithm depend on the size of the elemental volume (bin-size). On the other hand, these two parameters are independent of the bin-size but dependent on the number of histories sampled, for the Monte Carlo technique. At 0 deg. angle of inclination, where an analytical estimation is easily obtained, t...
Inequalities for Dual Quermassintegrals of Mixed Intersection Bodies
Zhao Chang-jian; Leng Gang-song
2005-02-01
In this paper, we first introduce a new concept of dual quermassintegral sum function of two star bodies and establish Minkowski’s type inequality for dual quermassintegral sum of mixed intersection bodies, which is a general form of the Minkowski inequality for mixed intersection bodies. Then, we give the Aleksandrov–Fenchel inequality and the Brunn–Minkowski inequality for mixed intersection bodies and some related results. Our results present, for intersection bodies, all dual inequalities for Lutwak’s mixed prosection bodies inequalities.
OPTIMASI KINERJA PROTOKOL AODV DENGAN STATIC INTERSECTION NODE
Johan Ericka Wahyu Prakasa
2016-07-01
Full Text Available VANET adalah sebuah pengembangan teknologi yang memungkinkan komunikasi antar kendaraan meskipun tidak terdapat koneksi secara langsung antara kendaraan yang berkomunikasi. Untuk meningkatkan performa protokol routing, maka pada penelitian ini akan ditambahkan SIN (Static Intersection Node. Static Intersection Node adalah RSU (Road Side Unit yang diletakkan di persimpangan jalan (intersection. Fungsi dari Static Intersection Node pada penelitian ini adalah sebagai repeater untuk membantu mengirimkan paket data ke kendaraan lain yang berada disekitarnya sehingga dapat meningkatkan Packet Delivery Ratio serta meminimalkan Packet Loss dan End to End Delay.
USING COVARIANCE INTERSECTION FOR CHANGE DETECTION IN REMOTE SENSING IMAGES
Yang Meng; Zhang Gong
2011-01-01
In this paper,an unsupervised change detection technique for remote sensing images acquired on the same geographical area but at different time instances is proposed by conducting Covariance Intersection (CI) to perform unsupervised fusion of the final fuzzy partition matrices from the Fuzzy C-Means (FCM) clustering for the feature space by applying compressed sampling to the given remote sensing images.The proposed approach exploits a CI-based data fusion of the membership function matrices,which are obtained by taking the Fuzzy C-Means (FCM) clustering of the frequency-domain feature vectors and spatial-domain feature vectors,aimed at enhancing the unsupervised change detection performance.Compressed sampling is performed to realize the image local feature sampling,which is a signal acquisition framework based on the revelation that a small collection of linear projections of a sparse signal contains enough information for stable recovery.The experimental results demonstrate that the proposed algorithm has a good change detection results and also performs quite well on denoising purpose.
Traffic Safety of Older Drivers in Various Types of Road Intersections
Tomaž Tollazzi
2010-05-01
Full Text Available In industrialized countries people over 50 years of age represent a rapidly growing part of population. Their lifestyle is also becoming more active, which means that the percentage of older drivers in the population of all drivers is also increasing. Many different studies have shown that elderly drivers are more frequently involved in specific types of accidents, especially at intersections. In the past 15 years there was a trend of increasing popularity of roundabouts in Slovenia. Their introduction was generally supported by the arguments of increased traffic-flow capacity and traffic safety as well. The studies on which these arguments are based were performed with an “ideal” type of driver in mind; the one that fully understands new rules and reacts correctly in all situations that may occur at such intersections, where there are no light signals to guide them. An elderly person does not necessarily conform to that ideal and if the percentage of elderly drivers became significant, the premises of the above mentioned studies may not be correct anymore which in turn implies that their results could also be questioned. The present study concentrated on the evaluation of traffic safety of elderly drivers, at various types of intersection, from their own perspective. Various statistical analyses of obtained data were performed. The most important finding was that we may claim, with high degree of probability, that the average person of the age of over 60 feels more unsafe at double-lane roundabouts than they would feel had the same intersection been equipped with traffic lights. Elderly traffic participants will always cause more accidents or participate in them due to hazardous factors. Challenge, arising from many different studies and researches, is in studying what measures and solutions can reduce the risk for elderly participants. KEYWORDS: traffic safety, road intersections, roundabouts, elderly people, older drivers
ON INTERSECTIONS OF INDEPENDENT NONDEGENERATE DIFFUSION PROCESSES
Zhenlong CHEN
2014-01-01
Let X(1) = {X(1)(s), s ∈ R+} and X(2) = {X(2)(t), t ∈ R+} be two inde-pendent nondegenerate diffusion processes with values in Rd. The existence and fractal dimension of intersections of the sample paths of X (1) and X (2) are studied. More gener-ally, let E1, E2⊆(0,∞) and F ⊂Rd be Borel sets. A necessary condition and a suffcient condition for P{X(1)(E1)∩X(2)(E2)∩F 6=∅}>0 are proved in terms of the Bessel-Riesz type capacity and Hausdorff measure of E1 × E2 × F in the metric space (R+× R+× Rd,ρb), whereρb is an unsymmetric metric defined in R+× R+× Rd. Under reasonable conditions, results resembling those of Browian motion are obtained.
Belonging and Unbelonging from an Intersectional Perspective
Christensen, Ann-Dorte
2009-01-01
The article is primarily theoretical and conceptual. It focuses on the notion of belonging from an intersectional perspective. The purpose is to discuss different dimensions of the concept of ‘belonging' and its rooting at different analytical levels. The first part of the article outlines...... the theoretical framework. The point of departure is multilayered citizenship and different notions of belonging. Second, the notion of belonging is divided into three analytical levels: (a) the macro level: imagined communities; (b) the meso level: collective organizations; and (c) the micro level: everyday......, for instance how to combine analysis of model citizenship/migration regimes with perspectives on everyday life. Another question relates to dilemmas within studies of everyday life. On the one hand, these studies are based on voices from below and a high degree of authenticity, but on the other hand, they tend...
Detecting Road Users at Intersections Through Changing Weather Using RGB-Thermal Videos
Bahnsen, Chris; Moeslund, Thomas B.
2015-01-01
and weather conditions. On this dataset, the detection performance of right turning vehicles, left turn- ing vehicles, and straight going cyclists are evaluated. Results from both systems show good performance when detecting turning vehicles with a precision of 0.90 and above depending on environmental...
Intersectional perspectives on intimate technology, solutionism, and privilege
Søndergaard, Marie Louise Juul; Hansen, Lone Koefoed
In this text, we discuss if and how an intersectional perspective on design may be critically practiced from a privileged position. More precisely, we ask how intersectional perspectives on race, gender and class may be useful in reflecting on and critically intervening in a privileged, Northern ...
A new proof of Faber's intersection number conjecture
Buryak, A
2009-01-01
We give a new proof of Faber's intersection number conjecture concerning the top intersections in the tautological ring of the moduli space of curves $\\M_g$. The proof is based on a very straightforward geometric and combinatorial computation with double ramification cycles.
Intersection of Three Planes Revisited--An Algebraic Approach
Trenkler, Götz; Trenkler, Dietrich
2017-01-01
Given three planes in space, a complete characterization of their intersection is provided. Special attention is paid to the case when the intersection set does not exist of one point only. Besides the vector cross product, the tool of generalized inverse of a matrix is used extensively.
Intersectionality and the Canadian Museum for Human Rights
Dhamoon, Rita Kaur; Hankivsky, Olena
2015-01-01
In this commentary, the authors propose than an intersectionality perspective can transform understandings of the contentious content of the Canadian Museum for Human Rights (CMHR). The use of an intersectionality perspective starts from the position that such discourses as racialization, gendering, capitalism, and ableism are mutually…
The Structure Theorem for Complete Intersections of Grade 4
Oh-Jin Kang; Hyoung J. Ko
2005-01-01
Serre showed that a Gorenstein ideal of grade 2 is a complete intersection, and Buchsbaum and Eisenbud proved a structure theorem for Gorenstein ideals of grade 3. It is found that a certain complete matrix defines a perfect ideal K3(f).As an application,we present a structure theorem for complete intersections of grade 4.
The Intersection of Gender and Age: An Exploration
Gander, Michelle
2014-01-01
The understanding of gender inequality for women entering work has not been subject to significant research or theorizing. This small study indicated that young women entering the workplace are subject to direct discrimination and by using an intersectionality approach this paper proposes that the intersection of gender and young age results in…
4-manifolds and intersection forms with local coefficients
Frøyshov, Kim Anders
2012-01-01
We extend Donaldson's diagonalization theorem to intersection forms with certain local coefficients, under some constraints. This provides new examples of non-smoothable topological 4-manifolds.......We extend Donaldson's diagonalization theorem to intersection forms with certain local coefficients, under some constraints. This provides new examples of non-smoothable topological 4-manifolds....
Modal intersection types, two-level languages, and staged synthesis
Henglein, Fritz; Rehof, Jakob
2016-01-01
A typed λ-calculus, λ∩ ⎕, is introduced, combining intersection types and modal types. We develop the metatheory of λ∩ ⎕, with particular emphasis on the theory of subtyping and distributivity of the modal and intersection type operators. We describe how a stratification of λ∩ ⎕ leads to a multi-linguistic...
The Ideal Intersection Property for Groupoid Graded Rings
Öinert, Per Johan; Lundström, Patrik
2012-01-01
We show that, if a groupoid graded ring has a grading satisfying a certain nondegeneracy property, then the commutant of the center of the principal component of the ring has the ideal intersection property, that is it intersects nontrivially every nonzero ideal of the ring. Furthermore, we show ...
The Intersection of Gender and Age: An Exploration
Gander, Michelle
2014-01-01
The understanding of gender inequality for women entering work has not been subject to significant research or theorizing. This small study indicated that young women entering the workplace are subject to direct discrimination and by using an intersectionality approach this paper proposes that the intersection of gender and young age results in…
Mahmudul Hasan
2014-08-01
Full Text Available Roundabouts have become increasingly popular in recent years as an innovative operational and safety solution at both low volume and high volume intersections. This paper contains capacity analysis of existing roads at a busy intersection in Dhaka named Polashi intersection, compare capacity and volume, AADT, velocity study, road user behavior, pedestrian flow analysis for proposed roundabout. Evaluations are made on a rational basis using qualitative analysis wherever possible and accepting that some matters determine by the exercise of judgments. Roundabouts have a number of advantages over traffic signals depending on the conditions. They reduce the severity of crashes since head-on and right-angle conflicts are nearly eliminated. They may consume less land area since turn pocket lanes are not needed. They have lower energy and maintenance costs
Self-Intersecting Periodic Curves in the Plane
Howie, J
2010-01-01
Suppose a smooth planar curve $\\gamma$ is $2\\pi$-periodic in the $x$ direction and the length of one period is $\\ell$. It is shown that if $\\gamma$ self-intersects, then it has a segment of length $\\ell- 2\\pi$ on which it self-intersects and somewhere its curvature is at least $2\\pi/(\\ell - 2\\pi)$. The proof involves the projection $\\Gamma$ of $\\gamma$ onto a cylinder. (The complex relation between $\\gamma$ and $\\Gamma$ was recently observed analytically by T. M. Apostol and M. A. Mnatsakanian. When $\\gamma$ is in general position there is a bijection between self-intersection points of $\\gamma$ modulo the periodicity, and self-intersection points of $\\Gamma$ with winding number 0 around the cylinder. However, our proof depends on the observation that a loop in $\\Gamma$ with winding number 1 leads to a self-intersection point of $\\gamma$.
Agustin, Lise Rolandsen; Lombardo, Emanuela
This paper explores the extent to which the emergence of an anti-discrimination policy in the European Union (EU) implies a shift in EU gender equality policies towards an intersectional approach. The frame analysis of EU gender equality policy documents shows that intersectional dimensions are i...
Spanners for geometric intersection graphs with applications
Martin Fürer
2012-05-01
Full Text Available A ball graph is an intersection graph of a set of balls with arbitrary radii. Given a real numbert>1, we say that a subgraph G' of a graph G is a t-spanner of G, if for every pair of verticesu,v in G, there exists a path in G' of length at most t times the distance between u and v inG. In this paper, we consider the problem of efficiently constructing sparse spanners of ball graphs which supports fast shortest path distance queries.We present the first algorithm for constructing spanners of ball graphs. For a ball graph in Rk, we construct a (1+ε-spanner for any ε>0 with O(nε-k+1 edges in O(n2ℓ+δε-k logℓ S time, using an efficient partitioning of space into hypercubes and solving intersection problems. Here ℓ=1-1/(⌊k/2⌋+2, δ is any positive constant, and S is the ratio between the largest and smallest radius. For the special case when the balls all have unit size, we show that the complexity of constructing a (1+ε-spanner is almost equal to the complexity of constructing a Euclidean minimum spanning tree. The algorithm extends naturally to other disk-likeobjects, also in higher dimensions.The algorithm uses an efficient subdivision of space to construct a sparse graph having many of the same distance properties as the input ball graph. Additionally, the constructed spanners have a small vertex separator decomposition (hereditary. In dimension k=2, the disk graph spanner has an O(n1/2ε-3/2+ε-3log S separator. The presence of a small separator is then exploited to obtain very efficient data structures for approximate distance queries. The results on geometric graph separators might be of independent interest. For example, since complete Euclidean graphs are just a special case of (unit ball graphs, our results also provide a new approach for constructing spanners with small separators in these graphs.
Tur\\'an and Ramsey Properties of Subcube Intersection Graphs
Johnson, J Robert
2011-01-01
The discrete cube $\\{0,1\\}^d$ is a fundamental combinatorial structure. A subcube of $\\{0,1\\}^d$ is a subset of $2^k$ of its points formed by fixing $k$ coordinates and allowing the remaining $d-k$ to vary freely. The subcube structure of the discrete cube is surprisingly complicated and there are many open questions relating to it. This paper is concerned with patterns of intersections among subcubes of the discrete cube. Two sample questions along these lines are as follows: given a family of subcubes in which no $r+1$ of them have non-empty intersection, how many pairwise intersections can we have? How many subcubes can we have if among them there are no $k$ which have non-empty intersection and no $l$ which are pairwise disjoint? These questions are naturally expressed as Tur\\'an and Ramsey type questions in intersection graphs of subcubes where the intersection graph of a family of sets has one vertex for each set in the family with two vertices being adjacent if the corresponding subsets intersect. Tur\\...
Tracer Flux Balance at an Urban Canyon Intersection
Carpentieri, Matteo; Robins, Alan G.
2010-05-01
Despite their importance for pollutant dispersion in urban areas, the special features of dispersion at street intersections are rarely taken into account by operational air quality models. Several previous studies have demonstrated the complex flow patterns that occur at street intersections, even with simple geometry. This study presents results from wind-tunnel experiments on a reduced scale model of a complex but realistic urban intersection, located in central London. Tracer concentration measurements were used to derive three-dimensional maps of the concentration field within the intersection. In combination with a previous study (Carpentieri et al., Boundary-Layer Meteorol 133:277-296, 2009) where the velocity field was measured in the same model, a methodology for the calculation of the mean tracer flux balance at the intersection was developed and applied. The calculation highlighted several limitations of current state-of-the-art canyon dispersion models, arising mainly from the complex geometry of the intersection. Despite its limitations, the proposed methodology could be further developed in order to derive, assess and implement street intersection dispersion models for complex urban areas.
Claros, Sharon Chia; Garcia, Gina A.; Johnston-Guerrero, Marc P.; Mata, Christine
2017-01-01
In this chapter, the authors share insights from a dialogue project focused on intersectionality within a residential life setting and discuss additional strategies for helping students understand intersectionality.
Component evolution in general random intersection graphs
Bradonjic, Milan [Los Alamos National Laboratory; Hagberg, Aric [Los Alamos National Laboratory; Hengartner, Nick [Los Alamos National Laboratory; Percus, Allon G [CLAREMONT GRADUATE UNIV.
2010-01-01
We analyze component evolution in general random intersection graphs (RIGs) and give conditions on existence and uniqueness of the giant component. Our techniques generalize the existing methods for analysis on component evolution in RIGs. That is, we analyze survival and extinction properties of a dependent, inhomogeneous Galton-Watson branching process on general RIGs. Our analysis relies on bounding the branching processes and inherits the fundamental concepts from the study on component evolution in Erdos-Renyi graphs. The main challenge becomes from the underlying structure of RIGs, when the number of offsprings follows a binomial distribution with a different number of nodes and different rate at each step during the evolution. RIGs can be interpreted as a model for large randomly formed non-metric data sets. Besides the mathematical analysis on component evolution, which we provide in this work, we perceive RIGs as an important random structure which has already found applications in social networks, epidemic networks, blog readership, or wireless sensor networks.
Narrating the Intersectionalities of Gender Violence: Editorial
Floretta Boonzaier
2015-12-01
Full Text Available The telling, sharing and, most critically, the hearing of stories related to gender violence has been a critical part of the project of feminism as well as the refuge movement (Dobash and Dobash 1979, Kelly 1988. This an introduction to a set of papers that represent highlights from the conference entitled “International Congress on Gender Violence: Intersectionalities” in terms of how the intersections of gender violence have been narrated. Contar, compartir, y, más críticamente, escuchar historias relacionadas con la violencia de género ha sido una parte fundamental del proyecto del feminismo, así como del movimiento de refugio (Dobash y Dobash 1979, Kelly 1988. Esta es una introducción a una serie de artículos representativos del Congreso Internacional sobre Violencia de Género: Intersecciones, que abordan cómo se han relatado las intersecciones de la violencia de género. DOWNLOAD THIS PAPER FROM SSRN: http://ssrn.com/abstract=2710203
The probability that a complete intersection is smooth
Bucur, Alina
2010-01-01
Given a smooth subscheme of a projective space over a finite field, we compute the probability that its intersection with a fixed number of hypersurface sections of large degree is smooth of the expected dimension. This generalizes the case of a single hypersurface, due to Poonen. We use this result to give a probabilistic model for the number of rational points of such a complete intersection. A somewhat surprising corollary is that the number of rational points on a random smooth intersection of two curves in projective 3-space is strictly less than the number of points on the projective line.
Political Intersectionality and Democratic Politics in the European Public Sphere
Siim, Birte
2015-01-01
intersections of gender and ethnic diversity in political life at the national and transnational levels across Europe. In this context, political intersectionality refers to the framing of gender and ethnic diversity by major political actors as well as by activities of women’s and anti-racist organisations...... Public Sphere (EPS). It is inspired by results and reflections from the European Gender Project (EGP) , where intersectionality was used as an approach for analysing negotiations between gender and ethno-national diversity in selected European countries and in relation to the European Public Sphere...
An efficient quantum scheme for Private Set Intersection
Shi, Run-hua; Mu, Yi; Zhong, Hong; Cui, Jie; Zhang, Shun
2016-01-01
Private Set Intersection allows a client to privately compute set intersection with the collaboration of the server, which is one of the most fundamental and key problems within the multiparty collaborative computation of protecting the privacy of the parties. In this paper, we first present a cheat-sensitive quantum scheme for Private Set Intersection. Compared with classical schemes, our scheme has lower communication complexity, which is independent of the size of the server's set. Therefore, it is very suitable for big data services in Cloud or large-scale client-server networks.
Open intersection numbers, matrix models and MKP hierarchy
Alexandrov, A
2014-01-01
In this paper we claim that the generating function of the intersection numbers on the moduli spaces of Riemann surfaces with boundary, constructed recently by R. Pandharipande, J. Solomon and R. Tessler and extended by A. Buryak, is a tau-function of the KP integrable hierarchy. Moreover, it is given by a simple modification of the Kontsevich matrix integral so that the generating functions of open and closed intersection numbers are described by the MKP integrable hierarchy. Virasoro constraints for the open intersection numbers naturally follow from the matrix integral representation.
ANALYTICAL AND MATHCAD INTERSECTION BETWEEN TWO PERPENDICULAR AXES CYLINDERS
PETRESCU Ligia
2015-06-01
Full Text Available The intersection of two surfaces is a common line to both surfaces. This line is often called transition line. The authors propose an analytical and a computer graphics intersection between two perpendicular axes cylinders. The analytical expression of such intersection will be obtained and transposed on the development of one cylinder. The distance between the two cylinders axes is essential in the aspect of the transition line. This transition line can be also obtained, using the computer, by the MathCAD programme. Some samples are relevant in this subject, according to the distance between the cylinders.
Open intersection numbers, matrix models and MKP hierarchy
Alexandrov, A. [Freiburg Institute for Advanced Studies (FRIAS), University of Freiburg,Albertstrasse 19, 79104 Freiburg (Germany); Mathematics Institute, University of Freiburg,Eckerstrasse 1, 79104 Freiburg (Germany); ITEP,Bolshaya Cheremushkinskaya 25, 117218 Moscow (Russian Federation)
2015-03-09
In this paper we conjecture that the generating function of the intersection numbers on the moduli spaces of Riemann surfaces with boundary, constructed recently by R. Pandharipande, J. Solomon and R. Tessler and extended by A. Buryak, is a tau-function of the KP integrable hierarchy. Moreover, it is given by a simple modification of the Kontsevich matrix integral so that the generating functions of open and closed intersection numbers are described by the MKP integrable hierarchy. Virasoro constraints for the open intersection numbers naturally follow from the matrix integral representation.
Inkjet patterning of multiline intersections for wirings in printed electronics.
Diaz, Elkin; Ramon, Eloi; Carrabina, Jordi
2013-10-08
Inkjet printed electronics using thermo-curable liquid inks exhibit particular geometrical characteristics in terms of regularity. This article presents a morphological analysis for inkjet printed multi line intersections that are critical structures for building circuits. We studied thin-film structures of silver conductive ink and printed by inkjet technology. Instability of the ink during printing causes the thickness irregularity of vertex, normally with peaks at these areas. We propose the usage of specific patterns for intersections as thickness regularity compensations. The results show that some patterns help to reduce this instability and improve the thickness regularity of intersections morphology.
Reconstructing Surface Triangulations by Their Intersection Matrices 26 September 2014
2015-01-01
The intersection matrix of a simplicial complex has entries equal to the rank of the intersecction of its facets. We prove that this matrix is enough to define up to isomorphism a triangulation of a surface.
A Unified Algorithm for Finding the Intersection Curve of Surfaces
谭建荣; 郑建民; 等
1994-01-01
In this papaer,an INTEGRAL CURVE ALGORITHM is presented,which turns the intersection curve of surfaces into the form of integral one and then uses “PREDICTORCORRECTOR” technique to evaluate the intersection of surfaces.No matter how the surfaces are defined,the method always deals with the intersection curves in the same way.To find a point on the curve one need only to calculate the JACOBI determinants of “PREDICTOR point”and “CORRECTOR point” while the second order precision is guatanteed.Thus,not only is the problem of finding the intersection of surfaces resolved,but also the algorithms for generating both plane curve and space curve are unified.
Intersection patterns of convex sets via simplicial complexes, a survey
Tancer, Martin
2011-01-01
The task of this survey is to present various results on intersection patterns of convex sets. One of main tools for studying intersection patterns is a point of view via simplicial complexes. We recall the definitions of so called $d$-representable, $d$-collapsible and $d$-Leray simplicial complexes which are very useful for this study. We study the differences among these notions and we also focus on computational complexity for recognizing them. A list of Helly-type theorems is presented in the survey and it is also discussed how (important) role play the above mentioned notions for the theorems. We also consider intersection patterns of good covers which generalize collections of convex sets (the sets may be `curvy'; however, their intersections cannot be too complicated). We mainly focus on new results.
Deformation of Singularities and the Homology of Intersection Spaces
Banagl, Markus
2011-01-01
While intersection cohomology is stable under small resolutions, both ordinary and intersection cohomology are unstable under smooth deformation of singularities. For complex projective algebraic hypersurfaces with an isolated singularity, we show that the first author's cohomology of intersection spaces is stable under smooth deformations in all degrees except possibly the middle, and in the middle degree precisely when the monodromy action on the cohomology of the Milnor fiber is trivial. In many situations, the isomorphism is shown to be a ring homomorphism induced by a continuous map. This is used to show that the rational cohomology of intersection spaces can be endowed with a mixed Hodge structure compatible with Deligne's mixed Hodge structure on the ordinary cohomology of the singular hypersurface.
Reduced Hamiltonian for intersecting shells and Hawking radiation
Menotti, Pietro
2010-01-01
We consider the dynamics of one or more self gravitating shells of matter in a centrally symmetric gravitational field in the Painleve' family of gauges. We give the reduced hamiltonian for two intersecting shells, both massless and massive. Such a formulation is applied to the computation of the semiclassical action of two intersecting shells. The relation of the imaginary part of the space-part of the action to the computation of the Bogoliubov coefficients is revisited.
MATHEMATICAL METHODS TO DETERMINE THE INTERSECTION CURVES OF THE CYLINDERS
POPA Carmen
2010-07-01
Full Text Available The aim of this paper is to establish the intersection curves between cylinders, by using the Mathematica program. This thing can be obtained by introducing the curves equations, which are inferred, in Mathematica program. This paper take into discussion three right cylinders and another inclined to 45 degrees. The intersection curves can also be obtained by using the classical methods of the descriptive geometry.
The OAFM magnet for ISR intersection I-8
CERN PhotoLab
1979-01-01
The Open Axial Field Magnet (OAFM), weighing in at 300 tons, was installed in ISR intersection I-8 and brought into operation early in 1979. Fitted with a highly transparent "flat-fish" vacuum chamber, it served experiment R807 (large transverse momentum). Flat-fish vacuum chambers were originally developed for use inside the Split-Field Magnet (SFM) at intersection I-4: see 8310325 and references there.
INTERSECTION OF MCMULLEN SET WITH ITS RATIONAL TRANSLATION
Meifeng Dai; Lixin Tang
2008-01-01
In this paper,we study the intersection of Mcmullen set with its rational translation.The main difficulty is that the generating structure of the intersection.By the radix expansion of translating vector,we give its fractal characterization.We find that the Hausdorff measure of these sets forms a discrete spectrum whose non-zero values come only from translating the vector(x,y)with its radix expansion.
Proceedings Sixth Workshop on Intersection Types and Related Systems
Graham-Lengrand, Stéphane; Paolini, Luca
2013-01-01
This volume contains the proceedings of the Sixth Workshop on Intersection Types and Related Systems (ITRS 2012). The workshop was held in Dubrovnik (Croatia) on June 29th, 2012, affiliated to Twenty-Seventh Annual ACM/IEEE Symposium on Logic in Computer Science (LICS 2012). The ITRS workshop aims to bring together researchers working on both the theory and practical applications of systems based on intersection types and related approaches (e.g., union types, refinement types, behavioural ty...
Estimation of air quality improvement at road and street intersections
Hoeglund, P.G. [Royal Inst. of Technology, Stockholm (Sweden). Traffic and Transport Planning
1995-12-31
There has always been a very great problem to quantify the detrimental exhaust air pollution related to the traffic flow, especially at road and street intersections. Until now model calculations have been developed mainly for the links between the intersections. In an attempt to remedy this situation the author has developed a method of estimating emissions on the micro level from motor vehicles at intersections as a help for infrastructural design related to improved environmental conditions. Very parsimonious knowledge exists regarding the deceleration and acceleration patterns at road- and street intersections. Not many surveys are done neither in Sweden nor within other countries. Evidently, the need for knowledge regarding deceleration and acceleration behaviour on the micro level has until now not been given priority. In traffic safety related research studies have been done describing the drivers` deceleration and acceleration behaviour and the vehicles` braking performance. Those results give deceleration data for extreme situations and are not useful for describing normal decelerations and accelerations at road- and street intersections. Environment related problems within the traffic flow analysis are now accentuating the need for the studying of special deceleration and acceleration behaviours in combination with an alternative design of the road and street infrastructure. There is a big difference in different vehicles` amount of emitted exhaust pollutions during the passing of intersections depending on the vehicles` speed levels related to their deceleration and acceleration levels. (author)
Intersecting Surface Defects and Two-Dimensional CFT
Gomis, Jaume; Pan, Yiwen; Peelaers, Wolfger
2016-01-01
We initiate the study of intersecting surface operators/defects in four-dimensional quantum field theories (QFTs). We characterize these defects by coupled 4d/2d/0d theories constructed by coupling the degrees of freedom localized at a point and on intersecting surfaces in spacetime to each other and to the four-dimensional QFT. We construct supersymmetric intersecting surface defects preserving just two supercharges in N = 2 gauge theories. These defects are amenable to exact analysis by localization of the partition function of the underlying 4d/2d/0d QFT. We identify the 4d/2d/0d QFTs that describe intersecting surface operators in N = 2 gauge theories realized by intersecting M2-branes ending on N M5-branes wrapping a Riemann surface. We conjecture and provide evidence for an explicit equivalence between the squashed four-sphere partition function of these intersecting defects and correlation functions in Liouville/Toda CFT with the insertion of arbitrary degenerate vertex operators, which are labeled by ...
Li, Bo; Liu, Richeng; Jiang, Yujing
2016-07-01
Fluid flow tests were conducted on two crossed fracture models for which the geometries of fracture segments and intersections were measured by utilizing a visualization technique using a CCD (charged coupled device) camera. Numerical simulations by solving the Navier-Stokes equations were performed to characterize the fluid flow at fracture intersections. The roles of hydraulic gradient, surface roughness, intersecting angle, and scale effect in the nonlinear fluid flow behavior through single fracture intersections were investigated. The simulation results of flow rate agreed well with the experimental results for both models. The experimental and simulation results showed that with the increment of the hydraulic gradient, the ratio of the flow rate to the hydraulic gradient, Q/J, decreases and the relative difference of Q/J between the calculation results employing the Navier-Stokes equations and the cubic law, δ, increases. When taking into account the fracture surface roughness quantified by Z2 ranging 0-0.42 for J = 1, the value of δ would increase by 0-10.3%. The influences of the intersecting angle on the normalized flow rate that represents the ratio of the flow rate in a segment to the total flow rate, Ra, and the ratio of the hydraulic aperture to the mechanical aperture, e/E, are negligible when J 10-2. Based on the regression analysis on simulation results, a mathematical expression was proposed to quantify e/E, involving variables of J and Rr, where Rr is the radius of truncating circles centered at an intersection. For E/Rr > 10-2, e/E varies significantly and the scale of model has large impacts on the nonlinear flow behavior through intersections, while for E/Rr < 10-3, the scale effect is negligibly small. Finally, a necessary condition to apply the cubic law to fluid flow through fracture intersections is suggested as J < 10-3, E/Rr < 10-3, and Z2 = 0.
Emmanuel Kwesi Nyantakyi
2014-03-01
Full Text Available Signalized intersections are vital nodal points in a transportation network and their efficiency of operation greatly influences the entire network's performance. Traffic simulation models have been widely used in both transportation operations and traffic analyses because simulation is safer, less expensive, and faster than field implementation and testing. This study assessed performance indication measures at Amakom intersection using micro simulation models in Synchro/SimTraffic. Traffic, geometric and signal control data including key parameters with greatest impact on the calibration process were collected on the field. At 5% significant level, the Chi square test and t-test analyses revealed that headway had a strong correlation with saturation flow compared to speed for both field and simulated conditions. It was concluded that changes in phasing plan with geometric improvement would improve upon the intersection’s level of service.
Gendered Violence, Intersectionalities and Resisting Gender Neutrality
Julie Stubbs
2015-12-01
Full Text Available Developments in feminist theory and research towards a more complex approach to gender relations and a more differentiated understanding of gendered violence have been positive but also have been the subject of significant debate. Some debates have long histories, while others mark more newly emergent concerns. In this paper I reflect on three areas of debate: intersectionality, complex gendering and complex inequalities; differentiating between forms of gendered violence (with a focus on intimate partner violence (IPV, and criminalisation. In each of these areas, feminist frameworks and knowledge concerning gendered violence have been challenged and the resurgence of gender neutral accounts has been notable. I argue that keeping a structural analysis to the fore provides the best way forward for constructive debate in the field aligned with feminist aspirations for the achievement of substantive equality. El desarrollo de la teoría feminista y la investigación hacia un enfoque más complejo de las relaciones de género y una comprensión más diferenciada de la violencia de género ha sido positivo, pero también ha sido objeto de un importante debate. Algunos debates tienen una larga historia, mientras que otros marcan preocupaciones emergentes surgidas en los últimos tiempos. En este trabajo se reflexiona sobre tres áreas de debate: interseccionalidad, configuración de géneros compleja y desigualdades complejas; diferenciación entre formas de violencia de género (fijándose en la violencia de pareja (VP; y la criminalización. En cada una de estas áreas, se han cuestionado los marcos feministas y el conocimiento relativo a la violencia de género, y ha sido notable el resurgimiento de cuentas de género neutro. Se defiende que fomentar un análisis estructural ofrece la mejor forma de fomentar un debate constructivo en el campo alineado con las aspiraciones feministas para el logro de una igualdad sustantiva. DOWNLOAD THIS PAPER FROM
Effect of Mixed Traffic Flow on Control Delay at Signalized ...
Effect of Mixed Traffic Flow on Control Delay at Signalized Intersections. ... Journal of Civil Engineering Research and Practice ... There are several methods available for operational analysis including mathematical models and traffic ...
Exploring the promises of intersectionality for advancing women's health research.
Hankivsky, Olena; Reid, Colleen; Cormier, Renee; Varcoe, Colleen; Clark, Natalie; Benoit, Cecilia; Brotman, Shari
2010-02-11
Women's health research strives to make change. It seeks to produce knowledge that promotes action on the variety of factors that affect women's lives and their health. As part of this general movement, important strides have been made to raise awareness of the health effects of sex and gender. The resultant base of knowledge has been used to inform health research, policy, and practice. Increasingly, however, the need to pay better attention to the inequities among women that are caused by racism, colonialism, ethnocentrism, heterosexism, and able-bodism, is confronting feminist health researchers and activists. Researchers are seeking new conceptual frameworks that can transform the design of research to produce knowledge that captures how systems of discrimination or subordination overlap and "articulate" with one another. An emerging paradigm for women's health research is intersectionality. Intersectionality places an explicit focus on differences among groups and seeks to illuminate various interacting social factors that affect human lives, including social locations, health status, and quality of life. This paper will draw on recently emerging intersectionality research in the Canadian women's health context in order to explore the promises and practical challenges of the processes involved in applying an intersectionality paradigm. We begin with a brief overview of why the need for an intersectionality approach has emerged within the context of women's health research and introduce current thinking about how intersectionality can inform and transform health research more broadly. We then highlight novel Canadian research that is grappling with the challenges in addressing issues of difference and diversity. In the analysis of these examples, we focus on a largely uninvestigated aspect of intersectionality research - the challenges involved in the process of initiating and developing such projects and, in particular, the meaning and significance of social
Exploring the promises of intersectionality for advancing women's health research
Clark Natalie
2010-02-01
Full Text Available Abstract Women's health research strives to make change. It seeks to produce knowledge that promotes action on the variety of factors that affect women's lives and their health. As part of this general movement, important strides have been made to raise awareness of the health effects of sex and gender. The resultant base of knowledge has been used to inform health research, policy, and practice. Increasingly, however, the need to pay better attention to the inequities among women that are caused by racism, colonialism, ethnocentrism, heterosexism, and able-bodism, is confronting feminist health researchers and activists. Researchers are seeking new conceptual frameworks that can transform the design of research to produce knowledge that captures how systems of discrimination or subordination overlap and "articulate" with one another. An emerging paradigm for women's health research is intersectionality. Intersectionality places an explicit focus on differences among groups and seeks to illuminate various interacting social factors that affect human lives, including social locations, health status, and quality of life. This paper will draw on recently emerging intersectionality research in the Canadian women's health context in order to explore the promises and practical challenges of the processes involved in applying an intersectionality paradigm. We begin with a brief overview of why the need for an intersectionality approach has emerged within the context of women's health research and introduce current thinking about how intersectionality can inform and transform health research more broadly. We then highlight novel Canadian research that is grappling with the challenges in addressing issues of difference and diversity. In the analysis of these examples, we focus on a largely uninvestigated aspect of intersectionality research - the challenges involved in the process of initiating and developing such projects and, in particular, the meaning
Ceunynck, T. de Polders, E. Daniels, S. Hermans, E. Brijs, T. & Wets, G.
2014-01-01
This study analyzes interactions between two vehicles at right-hand priority intersections and priority-controlled intersections and will help to gain a better insight into safety differences between both types of intersections. Data about yielding, looking behavior, drivers' age and gender,
PowerSet: A Comprehensive Visualization of Set Intersections.
Alsallakh, Bilal; Ren, Liu
2017-01-01
When analyzing a large amount of data, analysts often define groups over data elements that share certain properties. Using these groups as the unit of analysis not only reduces the data volume, but also allows detecting various patterns in the data. This involves analyzing intersection relations between these groups, and how the element attributes vary between these intersections. This kind of set-based analysis has various applications in a variety of domains, due to the generic and powerful notion of sets. However, visualizing intersections relations is challenging because their number grows exponentially with the number of sets. We present a novel technique based on Treemaps to provide a comprehensive overview of non-empty intersections in a set system in a scalable way. It enables gaining insight about how elements are distributed across these intersections as well as performing fine-grained analysis to explore and compare their attributes both in overview and in detail. Interaction allows querying and filtering these elements based on their set memberships. We demonstrate how our technique supports various use cases in data exploration and analysis by providing insights into set-based data, beyond the limits of state-of-the-art techniques.
Modeling Driver Behavior near Intersections in Hidden Markov Model.
Li, Juan; He, Qinglian; Zhou, Hang; Guan, Yunlin; Dai, Wei
2016-12-21
Intersections are one of the major locations where safety is a big concern to drivers. Inappropriate driver behaviors in response to frequent changes when approaching intersections often lead to intersection-related crashes or collisions. Thus to better understand driver behaviors at intersections, especially in the dilemma zone, a Hidden Markov Model (HMM) is utilized in this study. With the discrete data processing, the observed dynamic data of vehicles are used for the inference of the Hidden Markov Model. The Baum-Welch (B-W) estimation algorithm is applied to calculate the vehicle state transition probability matrix and the observation probability matrix. When combined with the Forward algorithm, the most likely state of the driver can be obtained. Thus the model can be used to measure the stability and risk of driver behavior. It is found that drivers' behaviors in the dilemma zone are of lower stability and higher risk compared with those in other regions around intersections. In addition to the B-W estimation algorithm, the Viterbi Algorithm is utilized to predict the potential dangers of vehicles. The results can be applied to driving assistance systems to warn drivers to avoid possible accidents.
Numerical simulations of Mach stem formation via intersecting bow shocks
Hansen, E. C.; Frank, A.; Hartigan, P.; Yirak, K.
2015-12-01
Hubble Space Telescope observations show bright knots of Hα emission within outflowing young stellar jets. Velocity variations in the flow create secondary bow shocks that may intersect and lead to enhanced emission. When the bow shocks intersect at or above a certain critical angle, a planar shock called a Mach stem is formed. These shocks could produce brighter Hα emission since the incoming flow to the Mach stem is parallel to the shock normal. In this paper we report first results of a study using 2-D numerical simulations designed to explore Mach stem formation at the intersection of bow shocks formed by hypersonic "bullets" or "clumps". Our 2-D simulations show how the bow shock shapes and intersection angles change as the adiabatic index γ changes. We show that the formation or lack of a Mach stem in our simulations is consistent with the steady-state Mach stem formation theory. Our ultimate goal, which is part of an ongoing research effort, is to characterize the physical and observational consequences of bow shock intersections including the formation of Mach stems.
Recombination of Intersecting D-Branes and Cosmological Inflation
Gómez-Reino, Marta
2002-01-01
We consider the interactions between Dp-branes intersecting at an arbitrary number of angles in the context of type II string theory. For cosmology purposes we concentrate in the theory on R^{3,1} x T^6. Interpreting the distance between the branes as the inflaton field, the branes can intersect at most at two angles in the compact space. If the configuration is non-supersymmetric we will have an interbrane potential that provides an effective cosmological inflationary epoch at the four dimensional intersection between the branes. The end of inflation occurs when the interbrane distance becomes small compared with the string scale, where a tachyon develops triggering the recombination of the branes. We study this recombination due to tachyon instabilities and we find the possibility for the final configuration to be again branes intersecting at two angles. This preserves the interesting features that are present in the intersecting brane models from the string model building point of view also after the end o...
2016-06-01
Bolivian indigenous identity. This chapter will focus on the interaction between political power and social organization from the pre-European era until...Bolivia’s gender parity index (GPI).163 The MAS administration’s Bono Juancito Pinto social subsidy, however, applies to all children who are...these programs became the primary tools for populist-style redistribution. This thesis analyzes the effectiveness of these social programs in
OPTIMIZATION OF URBAN MULTI-INTERSECTION TRAFFIC FLOW VIA Q-LEARNING
Yit Kwong Chin
2013-01-01
Full Text Available Congestions of the traffic flow within the urban traffic network have been a challenging task for all the urban developers. Many approaches have been introduced into the current system to solve the traffic congestion problems. Reconfiguration of the traffic signal timing plan has been carried out through implementation of different techniques. However, dynamic characteristics of the traffic flow increase the difficulties towards the ultimate solutions. Thus, traffic congestions still remain as unsolvable problems to the current traffic control system. In this study, artificial intelligence method has been introduced in the traffic light system to alter the traffic signal timing plan to optimize the traffic flows. Q-learning algorithm in this study has enhanced the traffic light system with learning ability. The learning mechanism of Q-learning enables traffic light intersections to release itself from traffic congestions situation. Adjacent traffic light intersections will work independently and yet cooperate with each others to a common goal of ensuring the fluency of the traffic flows within the traffic network. The simulated results show that the Q-Learning algorithm is able to learn from the dynamic traffic flow and optimize the traffic flow accordingly.
Development and evaluation of light rail transit signal priority strategies. Research report
Taylor, B.; Mechemehl, R.
1998-08-01
Light rail transit (LRT) signal priority strategies are often considered LRT vehicle delay reduction tools. The purpose of this research is to develop and evaluate LRT signal priority strategies to determine which strategies are most likely to produce significant delay reductions. A simulated median running LRT route in Austin, Texas is used for this case study. Both active and passive priority strategies are simulated using CORSIM with a Run-Time Extension (RTE). The RTE is used to provide the active priority signal timing changes associated with a green signal extension for the LRT phase. The results indicate that passive priority strategies are more effective in reducing delay. Among the passive methods, prohibition of left turns across the LRT tracks and one-way progression segmented to account for stops at LRT stations yield the best results.
Tools for analyzing intersecting tracks: The x2sys package
Wessel, Paul
2010-03-01
I present a new set of tools for detection of intersections among tracks in 2-D Cartesian or geographic coordinates. These tools allow for evaluation of crossover errors at intersections, analysis of such crossover errors to determine appropriate linear models of systematic corrections for each track, and application of these corrections and further adjustments to data that completely eliminates crossover discrepancies from final 2-D data compilations. Unlike my older x_system tools, the new x2sys tools implement modern algorithms for detecting track intersections and are capable of reading a wide range of data file formats, including data files following the netCDF COARDS convention. The x2sys package contains several programs that address the various tasks needed to undertake a comprehensive crossover analysis and is distributed as a supplement to the Generic Mapping Tools, making them available for all computer platforms and architectures.
The intersection of Finite State Automata and Definite Clause Grammars
Van Noord, G
1995-01-01
Bernard Lang defines parsing as the calculation of the intersection of a FSA (the input) and a CFG. Viewing the input for parsing as a FSA rather than as a string combines well with some approaches in speech understanding systems, in which parsing takes a word lattice as input (rather than a word string). Furthermore, certain techniques for robust parsing can be modelled as finite state transducers. In this paper we investigate how we can generalize this approach for unification grammars. In particular we will concentrate on how we might the calculation of the intersection of a FSA and a DCG. It is shown that existing parsing algorithms can be easily extended for FSA inputs. However, we also show that the termination properties change drastically: we show that it is undecidable whether the intersection of a FSA and a DCG is empty (even if the DCG is off-line parsable). Furthermore we discuss approaches to cope with the problem.
Optimal Locations of Bus Stops Connecting Subways near Urban Intersections
Yuan Cui
2015-01-01
Full Text Available Unsuitable locations of bus stops which provide feeder transportation connecting subways near urban intersections usually lead to the low efficiency of public transport and level of passenger service. A multiobjective optimization model to distribute such stop locations is proposed to attain the shortest total walk distance of passengers and minimum delay time of cars through intersections and travel time of buses. The Pareto frontier and optimal solutions for the proposed model are given by the distance-based and enumerative methods. The Xizhimen bus stop is selected to implement case studies for verifying the validity of the proposed model. The analysis of sensitivity on possible solutions is also carried out in the case studies. The results show that the proposed model is capable of optimizing the locations of bus stops connecting subways near intersections and helpful to improve the level of passengers service and operational efficiency of public transportation.
Self-organizing traffic lights at multiple-street intersections
Gershenson, Carlos
2011-01-01
Summary: Traffic light coordination is a complex problem. In this paper, we extend previous work on an abstract model of city traffic to allow for multiple street intersections. We test a self-organizing method in our model, showing that it is close to theoretical optima and superior to a traditional method of traffic light coordination. Abstract: The elementary cellular automaton following rule 184 can mimic particles flowing in one direction at a constant speed. This automaton can therefore model highway traffic. In a recent paper, we have incorporated intersections regulated by traffic lights to this model using exclusively elementary cellular automata. In such a paper, however, we only explored a rectangular grid. We now extend our model to more complex scenarios employing an hexagonal grid. This extension shows first that our model can readily incorporate multiple-way intersections and hence simulate complex scenarios. In addition, the current extension allows us to study and evaluate the behavior of two...
Beyond dichotomies: Gender and intersecting inequalities in climate change studies.
Djoudi, Houria; Locatelli, Bruno; Vaast, Chloe; Asher, Kiran; Brockhaus, Maria; Basnett Sijapati, Bimbika
2016-12-01
Climate change and related adaptation strategies have gender-differentiated impacts. This paper reviews how gender is framed in 41 papers on climate change adaptation through an intersectionality lens. The main findings show that while intersectional analysis has demonstrated many advantages for a comprehensive study of gender, it has not yet entered the field of climate change and gender. In climate change studies, gender is mostly handled in a men-versus-women dichotomy and little or no attention has been paid to power and social and political relations. These gaps which are echoed in other domains of development and gender research depict a 'feminization of vulnerability' and reinforce a 'victimization' discourse within climate change studies. We argue that a critical intersectional assessment would contribute to unveil agency and emancipatory pathways in the adaptation process by providing a better understanding of how the differential impacts of climate change shape, and are shaped by, the complex power dynamics of existing social and political relations.
On the intersections of Fibonacci, Pell, and Lucas numbers
Alekseyev, Max A
2010-01-01
We describe how to compute the intersection of two Lucas sequences of the forms $\\{U_n(P,\\pm 1) \\}_{n=0}^{\\infty}$ or $\\{V_n(P,\\pm 1) \\}_{n=0}^{\\infty}$ with $P\\in\\mathbb{Z}$ that includes sequences of Fibonacci, Pell, Lucas, and Lucas-Pell numbers. We prove that such an intersection is finite except for the case $U_n(1,-1)$ and $U_n(3,1)$ and the case of two $V$-sequences when the product of their discriminants is a perfect square. Moreover, the intersection in these cases also forms a Lucas sequence. Our approach relies on solving homogeneous quadratic Diophantine equations and Thue equations. In particular, we prove that 0, 1, 2, and 5 are the only numbers that are both Fibonacci and Pell, and list similar results for many other pairs of Lucas sequences. We further extend our results to Lucas sequences with arbitrary initial terms.
Dynamical Outcomes of Quenching: Reflections on a Conical Intersection
Lehman, Julia H.; Lester, Marsha I.
2014-04-01
This review focuses on experimental studies of the dynamical outcomes following collisional quenching of electronically excited OH A2Î£+ radicals by molecular partners. The experimental observables include the branching between reactive and nonreactive decay channels, kinetic energy release, and quantum state distributions of the products. Complementary theoretical investigations reveal regions of strong nonadiabatic coupling, known as conical intersections, which facilitate the quenching process. The dynamical outcomes observed experimentally are connected to the local forces and geometric properties of the nuclei in the conical intersection region. Dynamical calculations for the benchmark OH-H2 system are in good accord with experimental observations, demonstrating that the outcomes reflect the strong coupling in the conical intersection region as the system evolves from the excited electronic state to quenched products.
Teleparallel loop quantum cosmology in a system of intersecting branes
Alireza Sepehri
2016-09-01
Full Text Available Recently, some authors have removed the big bang singularity in teleparallel Loop Quantum Cosmology (LQC and have shown that the universe may undergo a number of oscillations. We investigate the origin of this type of teleparallel theory in a system of intersecting branes in M-theory in which the angle between them changes with time. This system is constructed by two intersecting anti-D8-branes, one compacted D4-brane and a D3-brane. These branes are built by joining M0-branes which develop in decaying fundamental strings. The compacted D4-brane is located between two intersecting anti-D8 branes and glues to one of them. Our universe is located on the D3 brane which wraps around the D4 brane from one end and sticks to one of the anti-D8 branes from the other one. In this system, there are three types of fields, corresponding to compacted D4 branes, intersecting branes and D3-branes. These fields interact with each other and make the angle between branes oscillate. By decreasing this angle, the intersecting anti-D8 branes approach each other, the D4 brane rolls, the D3 brane wraps around the D4 brane, and the universe contracts. By separating the intersecting branes and increasing the angle, the D4 brane rolls in the opposite direction, the D3 brane separates from it and the expansion branch begins. Also, the interaction between branes in this system gives us the exact form of the relevant Lagrangian for teleparallel LQC.
Teleparallel loop quantum cosmology in a system of intersecting branes
Sepehri, Alireza; Pradhan, Anirudh; Beesham, Aroonkumar; de Haro, Jaume
2016-09-01
Recently, some authors have removed the big bang singularity in teleparallel Loop Quantum Cosmology (LQC) and have shown that the universe may undergo a number of oscillations. We investigate the origin of this type of teleparallel theory in a system of intersecting branes in M-theory in which the angle between them changes with time. This system is constructed by two intersecting anti-D8-branes, one compacted D4-brane and a D3-brane. These branes are built by joining M0-branes which develop in decaying fundamental strings. The compacted D4-brane is located between two intersecting anti-D8 branes and glues to one of them. Our universe is located on the D3 brane which wraps around the D4 brane from one end and sticks to one of the anti-D8 branes from the other one. In this system, there are three types of fields, corresponding to compacted D4 branes, intersecting branes and D3-branes. These fields interact with each other and make the angle between branes oscillate. By decreasing this angle, the intersecting anti-D8 branes approach each other, the D4 brane rolls, the D3 brane wraps around the D4 brane, and the universe contracts. By separating the intersecting branes and increasing the angle, the D4 brane rolls in the opposite direction, the D3 brane separates from it and the expansion branch begins. Also, the interaction between branes in this system gives us the exact form of the relevant Lagrangian for teleparallel LQC.
Viewing equitable practices through the lens of intersecting identities
Lyons, Renée; Dsouza, Nikeetha; Quigley, Cassie
2016-04-01
This review explores Archer, Dawson, Seakins, and Wong's "Disorienting, fun or meaningful? Disadvantaged families' experiences of a science museum visit" by examining the analytic frameworks guiding this study. To expand on Archer et al.'s use of feminist post-structuralist theories of identity we draw from the theory of intersectionality to provide a more robust framework for analyzing barriers to engagement within an informal learning space. Our response to this work ends by exploring the types of solutions generated from an intersectionality framework—solutions aimed at transforming institutional programs and practices to create more equitable spaces for learning.
Viewing equitable practices through the lens of intersecting identities
Lyons, Renée; Dsouza, Nikeetha; Quigley, Cassie
2016-12-01
This review explores Archer, Dawson, Seakins, and Wong's "Disorienting, fun or meaningful? Disadvantaged families' experiences of a science museum visit" by examining the analytic frameworks guiding this study. To expand on Archer et al.'s use of feminist post-structuralist theories of identity we draw from the theory of intersectionality to provide a more robust framework for analyzing barriers to engagement within an informal learning space. Our response to this work ends by exploring the types of solutions generated from an intersectionality framework—solutions aimed at transforming institutional programs and practices to create more equitable spaces for learning.
New Approach to Measuring Traffic Queue at Intersections
SONG Lei; SHI Zhong-ke
2008-01-01
To measure the length of traffic queue, a vehicle motion model at intersections was built, and based on it the effective traffic queue was defined. Color images segmentation and frame differencing technique were used to detect the foreground and the moving vehicles by detecting regions of the images, and then measure the length of effective traffic queue. By processing the image sequence acquired at certain intersection, the results prove that it is able to work out the traffic queue effectively by using the two techniques.
Intersection democracy for winding branes and stabilization of extra dimensions
Rador, Tonguc
2005-01-01
We show that, in the context of pure Einstein gravity, a democratic principle for intersection possibilities of branes winding around extra dimensions in a given partitioning yield stabilization, while what the observed space follows is matter-like dust evolution . Here democracy is used in the sense that, in a given decimation of extra dimensions, all possible wrappings and hence all possible intersections are allowed. Generally, the necessary and sufficient condition for this is that the dimensionality $m$ of the observed space dimensions obey $3\\leqm \\le N$ where $N$ is the decimation order of the extra dimensions.
Third Wave Feminism's Unhappy Marriage of Poststructuralism and Intersectionality Theory
Susan Archer Mann
2013-06-01
Full Text Available This article first traces the history of unhappy marriages of disparate theoretical perspectives in US feminism. In recent decades, US third-wave authors have arranged their own unhappy marriage in that their major publications reflect an attempt to wed poststructuralism with intersectionality theory. Although the standpoint epistemology of intersectionality theory shares some common ground with the epistemology of poststructuralism, their epistemological assumptions conflict on a number of important dimensions. This contested terrain has generated serious debates within the third wave and between second- and thirdwave feminists. The form, content, and political implications of their "unhappy marriage" are the subject of this article.
1979-09-01
signal time in seconds on the 10-180 north-south roadway, if any. If there is no left turn signal and left turns are made through opposing traffic...seconds on the 10-180 east-west roadway, if any. If there is no left turn signal and left turns are made through opposing traffic during Phase I, enter a
The intersections between TRIZ and forecasting methodology
Georgeta BARBULESCU
2010-12-01
Full Text Available The authors’ intention is to correlate the basic knowledge in using the TRIZ methodology (Theory of Inventive Problem Solving or in Russian: Teoriya Resheniya Izobretatelskikh Zadatch as a problem solving tools meant to help the decision makers to perform more significant forecasting exercises. The idea is to identify the TRIZ features and instruments (40 inventive principles, i.e. for putting in evidence the noise and signal problem, for trend identification (qualitative and quantitative tendencies and support tools in technological forecasting, to make the decision-makers able to refine and to increase the level of confidence in the forecasting results. The interest in connecting TRIZ to forecasting methodology, nowadays, relates to the massive application of TRIZ methods and techniques for engineering system development world-wide and in growing application of TRIZ’s concepts and paradigms for improvements of non-engineering systems (including the business and economic applications.
Expert system for traffic signal setting assistance
Zozaya-Gorostiza, C.; Hendrickson, C.
1987-03-01
An experimental knowledge-based expert system to assist in traffic signal setting for isolated intersections is presented. In contrast to existing computer aids, the system can be applied to intersections of highly irregular geometries. Algorithmic processes to evaluate signal settings and decision tables to identify traffic flow conflicts are invoked by the expert system; phase distribution of flows is performed by applying heuristic rules. The system was written in the OPS5 export system environment. Advantages and disadvantages of the expert system programming approach relative to conventional algorithmic processes in the traffic engineering domain are described.
Zhang, Hong-Ze; Hu, Mao-Bin; Jia, Bin
2016-01-01
This paper has studied the minimum traffic delay at a two-phase intersection, taking into account the dynamical evolution process of queues. The feature of delay function has been studied, which indicates that the minimum traffic delay must be achieved when equality holds in at least one of the two constraints. We have derived the minimum delay as well as the corresponding traffic signal period, which shows that two situations are classified. Under certain circumstance, extra green time is needed for one phase while otherwise no extra green time should be assigned in both phases. Our work indicates that although the clearing policies were shown in many experiments to be optimal at isolated intersections, it is sometimes not the case.
Dyslexia, Mothering and Work: Intersecting Identities, Reframing, "Drowning" and Resistance
Skinner, Tina
2011-01-01
This paper focuses on the ways in which mothering, work and dyslexia intersect in lived experience. The theoretical framework used to interpret these experiences draws on competing discourses variously imposed on and internalised by the individual; however, it also stresses the ability (however limited) of the individual to reframe and therefore…
MULTIAGENT PLANNING OF INTERSECTION PASSAGE BY AUTONOMOUS VEHICLES
I. A. Zikratov
2016-09-01
Full Text Available We propose a traffic management system for autonomous vehicles that are agents at the intersection. In contrast to the known solutions based on the usage of semiautonomous control systems in assembly with the control unit, this algorithm is based on the principles of decentralized multiagent control. The best travel plan for intersection passage is produced by means of optimization methods jointly by all agents belonging to a dynamic collaboration of autonomous vehicles. The order of road intersection optimal for a given criterion is determined by the agents in the process of information exchange about themselves and environment. Our experiments show that this protocol can reduce significantly the traffic density as compared to the traditional systems of traffic management. Moreover, the effectiveness of the proposed algorithm increases with increasing density of road traffic. In addition, the absence of the critical object, that is the control unit, in the control system, reduces significantly the effectiveness of possible failures and hacker attacks on the intersection control system.
Exploring Driver Injury Severity at Intersection: An Ordered Probit Analysis
Yaping Zhang
2015-02-01
Full Text Available It is well known that intersections are the most hazardous locations; however, only little is known about driver injury severity in intersection crashes. Hence, the main goal of this study was to further examine the different factors contributing to driver injury severity involved in fatal crashes at intersections. Data used for the present analysis was from the US DOT-Fatality Analysis Reporting System (FARS crash database from the year 2011. An ordered probit model was employed to fit the fatal crash data and analyze the factors impacting each injury severity level. The analysis results displayed that driver injury severity is significantly affected by many factors. They include driver age and gender, driver ethnicity, vehicle type and age (years of use, crash type, driving drunk, speeding, violating stop sign, cognitively distracted driving, and seat belt usage. These findings from the current study are beneficial to form a solid basis for adopting corresponding measures to effectively drop injury severity suffering from intersection crash. More insights into the effects of risk factors on driver injury severity could be acquired using more advanced statistical models.
Intersectional Identity Negotiation: The Case of Young Immigrant Children
Compton-Lilly, Catherine; Papoi, Kristin; Venegas, Patricia; Hamman, Laura; Schwabenbauer, Briana
2017-01-01
We cast our lens on intersectional networks of identity negotiated by young children in immigrant families. Although some scholars discuss identity construction, we reference identity negotiation to capture the active, strategic, and agential work that we witnessed in our study. We begin by synthesizing relevant research on children's identity…
Intersecting Scapes and New Millennium Identities in Language Learning
Higgins, Christina
2015-01-01
This paper examines how flows of people, media, money, technology, and ideologies move through the world, with attention to how these scapes (Appadurai 1990, 1996, 2013) shape identity construction among language learners, both in and out of classrooms. After illustrating intersecting scapes in sociolinguistic terms, I explore the relevance of…
Simulation of Traffic on Intersection After Change of Traffic Priority
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”.
Conclusion: The Intersection of Student Voice and Policy Research
Mitra, Dana L.
2015-01-01
This concluding chapter examines how this book on student voice intersects with previous research about policy, especially policy implementation and sustainability. Mapping onto the themes of this volume, Discovering, Developing, and Demonstrating the power of student voice, I focus on three issues--legitimizing the role of young people in the…
INTERSECTION OF PRIME SUBMODULES AND DIMENSION OF MODULES
A. Azizi
2005-01-01
The aim of this paper is to study the conditions by which a P-prime submodule can be expressed as a finite intersection or union of P-prime submodules. Also corresponding to dimension and rank of modules, some equivalent conditions for a ring to be a Dedekind domain are given.
Intersectional Identity Negotiation: The Case of Young Immigrant Children
Compton-Lilly, Catherine; Papoi, Kristin; Venegas, Patricia; Hamman, Laura; Schwabenbauer, Briana
2017-01-01
We cast our lens on intersectional networks of identity negotiated by young children in immigrant families. Although some scholars discuss identity construction, we reference identity negotiation to capture the active, strategic, and agential work that we witnessed in our study. We begin by synthesizing relevant research on children's identity…
Intersecting Scapes and New Millennium Identities in Language Learning
Higgins, Christina
2015-01-01
This paper examines how flows of people, media, money, technology, and ideologies move through the world, with attention to how these scapes (Appadurai 1990, 1996, 2013) shape identity construction among language learners, both in and out of classrooms. After illustrating intersecting scapes in sociolinguistic terms, I explore the relevance of…
Acoustic analysis of a semi-anechoic chamber with intersection
P. Nassiri
2014-05-01
.Conclusion: According to the results, it can be concluded that the suggested intersection layout of rectangular fibrous absorbents can be used as a reliable method in order to reduce the reverberation time and to gain lower cut-off frequency for construct a semi anechoic chamber with the high efficiency.
Becoming Black Women: Intimate Stories and Intersectional Identities
Wilkins, Amy C.
2012-01-01
In this article, I argue that intimate stories are an important resource for the achievement of intersectional identities. Drawing on in-depth interviews with black college students at two predominantly white universities, I examine the stories black college women tell about interracial relationships between black men and white women. I argue that…
Intersections of Spirituality, Religion and Gender in Children's Literature
Trousdale, Ann M.
2005-01-01
This paper explores the intersections of spirituality, religion and gender in contemporary children's books published in the United States. Background for the discussion includes a history of religion in children's literature and the history of women's roles in the Christian tradition. Representative works of realistic fiction--historical and…
Leaf-wise intersections and Rabinowitz Floer homology
Albers, Peter
2008-01-01
In this article we explain how critical points of a perturbed Rabinowitz action functional give rise to leaf-wise intersection points in hypersurfaces of restricted contact type. This is used to derive existence results for hypersurfaces in general exact symplectic manifolds.
Precision of Points Computed from Intersections of Lines or Planes
Cederholm, Jens Peter
2004-01-01
estimates the precision of the points. When using laser scanning a similar problem appears. A laser scanner captures a 3-D point cloud, not the points of real interest. The suggested method can be used to compute three-dimensional coordinates of the intersection of three planes estimated from the point...
Design unbiased estimation in line intersect sampling using segmented transects
David L.R. Affleck; Timothy G. Gregoire; Harry T. Valentine; Harry T. Valentine
2005-01-01
In many applications of line intersect sampling. transects consist of multiple, connected segments in a prescribed configuration. The relationship between the transect configuration and the selection probability of a population element is illustrated and a consistent sampling protocol, applicable to populations composed of arbitrarily shaped elements, is proposed. It...
Traffic noise and vehicle movement at a controlled intersection
Salomons, E.M.
2014-01-01
Traffic noise at an intersection controlled by traffic lights shows noise level variations due to the alternating green and red lights for the different trafficstreams. Noise peaks caused by automobiles pulling up or passing by at highspeed may be quite annoying for people living near the intersecti
Intersections of Loops and the Andersen-Mattes-Reshetikhin Algebra
Cahn, Patricia
2011-01-01
Given two free homotopy classes $\\alpha_1, \\alpha_2$ of loops on an oriented surface, it is natural to ask how to compute the minimum number of intersection points $m(\\alpha_1, \\alpha_2)$ of loops in these two classes. We show that for $\\alpha_1\
Using Dynamic Geometry Software for the Intersection Surfaces
Koparan, Timur; Yilmaz, Gül Kaleli
2015-01-01
The purpose of this study is to define prospective teacher views about using dynamic geometry software for intersection surfaces. The study was conducted as a case study. For this purpose, data collection tool was developed based on the opinion of two experts. The data collection tool consists of 4 open-ended questions related to the intersection…
Teleparallel loop quantum cosmology in a system of intersecting branes
Sepehri, Alireza; Beesham, A; de Haro, Jaume
2016-01-01
Recently, some authors have removed the big bang singularity in teleparallel Loop Quantum Cosmology (LQC) and have shown that the universe may undergo a number of oscillations. We investigate the origin of this type of teleparallel theory in a system of intersecting branes in M-theory in which the angle between them changes with time. This system is constructed by two intersecting anti-D8-branes, one compacted D4-brane and the other a D3-brane. These branes are built by joining M0-branes which develop in decaying fundamental strings. The compacted D4-brane is located between two intersecting anti-D8 branes and glues to one of them. Our universe is located on the D3 brane which wraps the D4 brane from one end and sticks to one of the anti-D8 branes from another one. In this system, there are three types of ?elds, corresponding to compacted D4 branes, intersecting branes and D3-branes. These ?elds interact with each other and make the angle between branes oscillate. By decreasing this angle and approaching the ...
Disciplinarity and Methodology in Intersectionality Theory and Research
Syed, Moin
2010-01-01
Comments on the original article, "Intersectionality and research in psychology," by E. R. Cole. Cole's article, says the current author, makes a welcome and valuable contribution to the field of psychology. Particularly useful are the three questions that she posed, highlighting how these questions are relevant and pressing for all researchers,…
Response to Mary J. Reichling, "Intersections: Form, Feeling, and Isomorphism"
Sinclair, Anne
2004-01-01
In her response to Mary Reichling's article "Intersections: Form, Feeling, and Isomorphism, Anne Sinclair believes that the exploration of form, feeling, and isomorphism in the writings of Susanne Langer accomplishes its goal to examine and elucidate aspects of these concepts. Sinclair finds several of the ideas presented very engaging. Musical…
Threshold Functions in Random s-Intersection Graphs
Zhao, Jun; Gligor, Virgil
2015-01-01
Random $s$-intersection graphs have recently received considerable attention in a wide range of application areas. In such a graph, each vertex is equipped with a set of items in some random manner, and any two vertices establish an undirected edge in between if and only if they have at least $s$ common items. In particular, in a uniform random $s$-intersection graph, each vertex independently selects a fixed number of items uniformly at random from a common item pool, while in a binomial random $s$-intersection graph, each item in some item pool is independently attached to each vertex with the same probability. For binomial/uniform random $s$-intersection graphs, we establish threshold functions for perfect matching containment, Hamilton cycle containment, and $k$-robustness, where $k$-robustness is in the sense of Zhang and Sundaram [IEEE Conf. on Decision & Control '12]. We show that these threshold functions resemble those of classical Erd\\H{o}s-R\\'{e}nyi graphs, where each pair of vertices has an un...
Revisiting Street Intersections Using Slot-Based Systems.
Remi Tachet
Full Text Available Since their appearance at the end of the 19th century, traffic lights have been the primary mode of granting access to road intersections. Today, this centuries-old technology is challenged by advances in intelligent transportation, which are opening the way to new solutions built upon slot-based systems similar to those commonly used in aerial traffic: what we call Slot-based Intersections (SIs. Despite simulation-based evidence of the potential benefits of SIs, a comprehensive, analytical framework to compare their relative performance with traffic lights is still lacking. Here, we develop such a framework. We approach the problem in a novel way, by generalizing classical queuing theory. Having defined safety conditions, we characterize capacity and delay of SIs. In the 2-road crossing configuration, we provide a capacity-optimal SI management system. For arbitrary intersection configurations, near-optimal solutions are developed. Results theoretically show that transitioning from a traffic light system to SI has the potential of doubling capacity and significantly reducing delays. This suggests a reduction of non-linear dynamics induced by intersection bottlenecks, with positive impact on the road network. Such findings can provide transportation engineers and planners with crucial insights as they prepare to manage the transition towards a more intelligent transportation infrastructure in cities.
Revisiting Street Intersections Using Slot-Based Systems.
Tachet, Remi; Santi, Paolo; Sobolevsky, Stanislav; Reyes-Castro, Luis Ignacio; Frazzoli, Emilio; Helbing, Dirk; Ratti, Carlo
2016-01-01
Since their appearance at the end of the 19th century, traffic lights have been the primary mode of granting access to road intersections. Today, this centuries-old technology is challenged by advances in intelligent transportation, which are opening the way to new solutions built upon slot-based systems similar to those commonly used in aerial traffic: what we call Slot-based Intersections (SIs). Despite simulation-based evidence of the potential benefits of SIs, a comprehensive, analytical framework to compare their relative performance with traffic lights is still lacking. Here, we develop such a framework. We approach the problem in a novel way, by generalizing classical queuing theory. Having defined safety conditions, we characterize capacity and delay of SIs. In the 2-road crossing configuration, we provide a capacity-optimal SI management system. For arbitrary intersection configurations, near-optimal solutions are developed. Results theoretically show that transitioning from a traffic light system to SI has the potential of doubling capacity and significantly reducing delays. This suggests a reduction of non-linear dynamics induced by intersection bottlenecks, with positive impact on the road network. Such findings can provide transportation engineers and planners with crucial insights as they prepare to manage the transition towards a more intelligent transportation infrastructure in cities.
Numerical Simulations of Mach Stem Formation via Intersecting Bow Shocks
Hansen, Edward C; Hartigan, Patrick
2014-01-01
Hubble Space Telescope observations show bright knots of H$\\alpha$ emission within outflowing young stellar jets. Velocity variations in the flow create secondary bow shocks that may intersect and lead to enhanced emission. When the bow shocks intersect at or above a certain critical angle, a planar shock called a Mach stem is formed. These shocks could produce brighter H$\\alpha$ emission since the incoming flow to the Mach stem is parallel to the shock normal. In this paper we report first results of a study using 2-D numerical simulations designed to explore Mach stem formation at the intersection of bow shocks formed by hypersonic "bullets" or "clumps". Our 2-D simulations show how the bow shock shapes and intersection angles change as the adiabatic index $\\gamma$ changes. We show that the formation or lack of a Mach stem in our simulations is consistent with the steady-state Mach stem formation theory. Our ultimate goal, which is part of an ongoing research effort, is to characterize the physical and obse...
The Intersection of Science and Politics
Kim, Elias
2016-03-01
Politics and science often seem at odds. However, important political issues like climate change, cybersecurity, and space exploration require the input of both communities. To create the best possible policies, there must be a dialogue between politicians and scientists. SPS and John Mather gave me the opportunity to be part of this dialogue. Through the Mather Policy Internship, I worked for the House Committee on Energy and Commerce, which has jurisdiction over telecom, health care, energy supply, and other technical areas. I worked with the technology and communications subcommittee, conducting research on cybersecurity, spectrum auctions, and the internet of things. It is clear that even the commercial side of science would benefit from the help of the science community. My background gave me an edge over the other interns; I didn't need to learn what it meant for there to be signals of different wavelength. Most importantly, I learned what it will take to pursue a career in science policy. For the number of physics undergrads who do not wish to pursue a pure physics career, science policy is a strong option. Scientists bring a rigorous, fact-based approach that might benefit the political world as a whole. Thanks to SPS, AIP, and the John and Jane Mather Foundation for Science and the Arts.
Some insights into the intersection of physical planning and governance in Zimbabwe
Chakwizira, J
2008-04-01
Full Text Available This paper presents some insights into the intersection of physical planning and governance in Zimbabwe. It argues that the major theoretical, policy and practice discourses - explaining the intersection of physical planning and governance - relate...
EnviroAtlas - Paterson, NJ - Estimated Intersection Density of Walkable Roads
U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates the intersection density of walkable roads within a 750 meter radius of any given 10 meter pixel in the community. Intersections...
EnviroAtlas - Minneapolis/St. Paul, MN - Estimated Intersection Density of Walkable Roads
U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates the intersection density of walkable roads within a 750 meter radius of any given 10 meter pixel in the community. Intersections...
EnviroAtlas - New Bedford, MA - Estimated Intersection Density of Walkable Roads
U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates the intersection density of walkable roads within a 750 meter radius of any given 10 meter pixel in the community. Intersections...
EnviroAtlas - Pittsburgh, PA - Estimated Intersection Density of Walkable Roads
U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates the intersection density of walkable roads within a 750 meter radius of any given 10 meter pixel in the community. Intersections...
EnviroAtlas - New York, NY - Estimated Intersection Density of Walkable Roads
U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates the intersection density of walkable roads within a 750 meter radius of any given 10 meter pixel in the community. Intersections...
EnviroAtlas - Memphis, TN - Estimated Intersection Density of Walkable Roads
U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates the intersection density of walkable roads within a 750 meter radius of any given 10 meter pixel in the community. Intersections...
EnviroAtlas - Cleveland, OH - Estimated Intersection Density of Walkable Roads
U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates the intersection density of walkable roads within a 750 meter radius of any given 10 meter pixel in the community. Intersections...
EnviroAtlas - Fresno, CA - Estimated Intersection Density of Walkable Roads
U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates the intersection density of walkable roads within a 750 meter radius of any given 10 meter pixel in the community. Intersections...
EnviroAtlas - Green Bay, WI - Estimated Intersection Density of Walkable Roads
U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates the intersection density of walkable roads within a 750 meter radius of any given 10 meter pixel in the community. Intersections...
EnviroAtlas - Tampa, FL - Estimated Intersection Density of Walkable Roads
U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates the intersection density of walkable roads within a 750 meter radius of any given 10 meter pixel in the community. Intersections...
EnviroAtlas - Portland, ME - Estimated Intersection Density of Walkable Roads
U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates the intersection density of walkable roads within a 750 meter radius of any given 10 meter pixel in the community. Intersections...
EnviroAtlas - Phoenix, AZ - Estimated Intersection Density of Walkable Roads
U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates the intersection density of walkable roads within a 750 meter radius of any given 10 meter pixel in the community. Intersections...
EnviroAtlas - Des Moines, IA - Estimated Intersection Density of Walkable Roads
U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates the intersection density of walkable roads within a 750 meter radius of any given 10 meter pixel in the community. Intersections...
EnviroAtlas - Austin, TX - Estimated Intersection Density of Walkable Roads
U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates the intersection density of walkable roads within a 750 meter radius of any given 10 meter pixel in the community. Intersections...
EnviroAtlas - Woodbine, IA - Estimated Intersection Density of Walkable Roads
U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates the intersection density of walkable roads within a 750 meter radius of any given 10 meter pixel in the community. Intersections...
EnviroAtlas - Milwaukee, WI - Estimated Intersection Density of Walkable Roads
U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates the intersection density of walkable roads within a 750 meter radius of any given 10 meter pixel in the community. Intersections...
EnviroAtlas - Portland, OR - Estimated Intersection Density of Walkable Roads
U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates the intersection density of walkable roads within a 750 meter radius of any given 10 meter pixel in the community. Intersections...
EnviroAtlas - Durham, NC - Estimated Intersection Density of Walkable Roads
U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates the intersection density of walkable roads within a 750 meter radius of any given 10 meter pixel in the community. Intersections...
单点相位交叉口两难区主动控制研究%Research on Proactive Control of Dilemma Zone for Isolated Intersections
马国胜; 黄玮
2013-01-01
为改善交叉口安全状况，提高整个交叉口的交通安全水平，考虑到交叉口因信号控制不当造成的事故原因，重点对两难区的驾驶行为进行了分析。为克服以往研究中车辆以匀速状态通过交叉口的不合理性，实时保障车辆在信号控制交叉口不发生碰撞事故，尤其是两难区的存在导致的追尾、侧面碰撞事故，提出了考虑驾驶行为的交叉口交通信号主动控制策略并对控制策略的有效性进行了仿真验证。仿真结果表明，交叉口交通信号主动控制策略有效地提高了交叉口车辆的安全性，为道路交叉口防撞提供了新方法。%Improper signal timing is a main cause of traffic accidents at road intersections.This paper studies signal control strategies regarding traffic safety.To avoid the unreasonable assumption of average traveling speed for vehicles,the paper first analyzes the driving behavior in dilemma zone at intersections.Proactive signal con-trol based on different driving behavior is proposed.Simulation results show that the strategy of proactive control can effectively improve intersection safety at the signalized intersections.It provides a new approach to collision avoidance at road intersections.
Crossing at a Red Light: Behavior of Cyclists at Urban Intersections
Xiaobao Yang
2012-01-01
Full Text Available To investigate the relationship between cyclist violation and waiting duration, the red-light running behavior of nonmotorized vehicles is examined at signalized intersections. Violation waiting duration is collected by video cameras and it is assigned as censored and uncensored data to distinguish between normal crossing and red-light running. A proportional hazard-based duration model is introduced, and variables revealing personal characteristics and traffic conditions are used to describe the effects of internal and external factors. Empirical results show that the red-light running behavior of cyclist is time dependent. Cyclist’s violating behavior represents positive duration dependence, that the longer the waiting time elapsed, the more likely cyclists would end the wait soon. About 32% of cyclists are at high risk of violation and low waiting time to cross the intersections. About 15% of all the cyclists are generally nonrisk takers who can obey the traffic rules after waiting for 95 seconds. The human factors and external environment play an important role in cyclists’ violation behavior. Minimizing the effects of unfavorable condition in traffic planning and designing may be an effective measure to enhance traffic safety.
A Reliability-Based Analysis of Bicyclist Red-Light Running Behavior at Urban Intersections
Mei Huan
2015-01-01
Full Text Available This paper describes the red-light running behavior of bicyclists at urban intersections based on reliability analysis approach. Bicyclists’ crossing behavior was collected by video recording. Four proportional hazard models by the Cox, exponential, Weibull, and Gompertz distributions were proposed to analyze the covariate effects on safety crossing reliability. The influential variables include personal characteristics, movement information, and situation factors. The results indicate that the Cox hazard model gives the best description of bicyclists’ red-light running behavior. Bicyclists’ safety crossing reliabilities decrease as their waiting times increase. There are about 15.5% of bicyclists with negligible waiting times, who are at high risk of red-light running and very low safety crossing reliabilities. The proposed reliability models can capture the covariates’ effects on bicyclists’ crossing behavior at signalized intersections. Both personal characteristics and traffic conditions have significant effects on bicyclists’ safety crossing reliability. A bicyclist is more likely to have low safety crossing reliability and high violation risk when more riders are crossing against the red light, and they wait closer to the motorized lane. These findings provide valuable insights in understanding bicyclists’ violation behavior; and their implications in assessing bicyclists’ safety crossing reliability were discussed.
Selection of MOSFET Sizes by Fuzzy Sets Intersection in the Feasible Solutions Space
S. Polanco-Martagón
2012-06-01
Full Text Available A fuzzy sets intersection procedure to select the optimum sizes of analog circuits composed of metal-oxidesemiconductorfield-effect-transistors (MOSFETs, is presented. The cases of study are voltage followers (VFs and acurrent-feedback operational amplifier (CFOA, where the width (W and length (L of the MOSFETs are selected fromthe space of feasible solutions computed by swarm or evolutionary algorithms. The evaluation of three objectives,namely: gain, bandwidth and power consumption; is performed using HSPICETM with standard integrated circuit (ICtechnology of 0.35μm for the VFs and 180nm for the CFOA. Therefore, the intersection procedure among three fuzzysets representing “gain close to unity”, ”high bandwidth” and “minimum power consumption”, is presented. The mainadvantage relies on its usefulness to select feasible W/L sizes automatically but by considering deviation percentagesfrom the desired target specifications. Basically, assigning a threshold to each fuzzy set does it. As a result, theproposed approach selects the best feasible sizes solutions to guarantee and to enhance the performances of the ICsin analog signal processing applications.
Traffic signal design and simulation for vulnerable road users safety and bus preemption
Lo, Shih-Ching; Huang, Hsieh-Chu
2015-01-01
Mostly, pedestrian car accidents occurred at a signalized interaction is because pedestrians cannot across the intersection safely within the green light. From the viewpoint of pedestrian, there might have two reasons. The first one is pedestrians cannot speed up to across the intersection, such as the elders. The other reason is pedestrians do not sense that the signal phase is going to change and their right-of-way is going to be lost. Developing signal logic to protect pedestrian, who is crossing an intersection is the first purpose of this study. In addition, to improve the reliability and reduce delay of public transportation service is the second purpose. Therefore, bus preemption is also considered in the designed signal logic. In this study, the traffic data of the intersection of Chong-Qing North Road and Min-Zu West Road, Taipei, Taiwan, is employed to calibrate and validate the signal logic by simulation. VISSIM 5.20, which is a microscopic traffic simulation software, is employed to simulate the signal logic. From the simulated results, the signal logic presented in this study can protect pedestrians crossing the intersection successfully. The design of bus preemption can reduce the average delay. However, the pedestrian safety and bus preemption signal will influence the average delay of cars largely. Thus, whether applying the pedestrian safety and bus preemption signal logic to an intersection or not should be evaluated carefully.
COTRUMBĂ Mirela
2015-06-01
Full Text Available This paper presents how descriptive geometry contributes to the achievement of intersections of simple objects and isometric axonometric representation of these intersections. It also highlights the role of descriptive geometry on acquiring skills in Technical Drawing, in representation of objects intersection. All illustrations in this paper are made using Microsoft Office Word Drawing Toolbar and AutoCAD software.
Thermodynamics of Intersecting Black Branes from Interacting Elementary Branes
Morita, Takeshi
2015-01-01
If an Einstein-Maxwell-Dilaton system admits the extreme brane solution in which no force works between the parallel branes, the collective motion of nearly parallel branes exhibits the thermodynamical properties which are coincident with those of the corresponding black branes at low energy regime (up to unfixed numerical factors). Hence it may provide the microscopic description of the black branes ($p$-soup proposal). This fact motivates us to test this proposal in the intersecting black branes which have multiple brane charges and/or momentum along the brane direction. We consider the case that the multiple branes satisfy the intersection rule and feel no force when they are static, and find the agreement to the black hole thermodynamics.
Fat People of Color: Emergent Intersectional Discourse Online
Apryl A. Williams
2017-02-01
Full Text Available Though the general populace has been introduced to the idea of thin privilege, the fat activist movement has been slow in gaining momentum. This is due, in part, to the symbolic annihilation of “fat” people in media. Within the fat activist framework, women of color are often further excluded from the overarching discourse and white privilege is sometimes unacknowledged. Taking an intersectional approach, I examine the Tumblr page, Fat People of Color. I use Critical Technocultural Discourse Analysis (CTDA to examine the images and conversations posted by users. Findings reveal that Fat People of Color uses an intersectional, communal approach to posit counter-narratives against normative ideas about white thinness. This research contributes to an understudied area of sociological inquiry by presenting an analysis of the experience of “fat” women of color within a feminist framework. Ignoring the variation of experiences strengthens the types of privileges that fat activism and feminism hope to dismantle.
A New Data Layout For Set Intersection on GPUs
Amossen, Rasmus Resen; Pagh, Rasmus
2011-01-01
Set intersection is the core in a variety of problems, e.g. frequent itemset mining and sparse boolean matrix multiplication. It is well-known that large speed gains can, for some computational problems, be obtained by using a graphics processing unit (GPU) as a massively parallel computing device....... However, GPUs require highly regular control flow and memory access patterns, and for this reason previous GPU methods for intersecting sets have used a simple bitmap representation. This representation requires excessive space on sparse data sets. In this paper we present a novel data layout, BATMAP....... The main finding is that our method is able to achieve speedups over both Apriori and FP-growth when the number of distinct items is large, and the density of the problem instance is above 1%. Previous implementations of frequent itemset mining on GPU have not been able to show speedups over the best...
Intersections of S-branes with waves and monopoles
Besken, Mert, E-mail: mbesken@physics.ucla.edu [Dept. of Physics and Astronomy, University of California, Los Angeles, CA 90095 (United States); Deger, Nihat Sadik, E-mail: sadik.deger@boun.edu.tr [Dept. of Mathematics, Bogazici University, Bebek, 34342 Istanbul (Turkey)
2015-05-15
We construct intersections of S-branes with waves and Kaluza–Klein monopoles. There are several possible ways to add a monopole to an S-brane solution similar to p-branes. On the other hand, one may add a wave only to the transverse space of an S-brane unlike a p-brane where wave resides on its worldvolume. The metric function of the wave is a harmonic function of the remaining transverse directions and an extra condition on integration constants is needed. We also show that it is not possible to add an S-brane to p-brane intersections whose near horizon geometry has an AdS part.
Intersection of a Sure Ellipsoid and a Random Ellipsoid
Arjun K. Gupta
2012-07-01
Full Text Available Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif";} An Expression for the expected value of the intersection of a sure sphere and a random sphere has been derived by Laurent (1974. In the present paper we derive the expression for the expected intersection volume of a sure ellipsoid and a random ellipsoid
SOFTWARE FOR SYNTHESIS OF COMPLIANT MECHANISMS WITHOUT INTERSECTING ELEMENTS
Andrija P. Milojević
2014-01-01
Full Text Available A compliant mechanism is defined as a single piece structure that transfer motion or force through elastic deformation. The synthesis of this kind of mechanisms represents a challenging task, especially because their flexible segments usually must undergo large, nonlinear deflections which include difficult nonlinear analysis. In this paper the new software for synthesis of compliant mechanisms is developed. The software uses an improved topology optimization technique that is especially useful when the designer does not have a particular compliant mechanism already in mind. Intersection between elements in the compliant mechanisms obtained by using existing topology optimization technique often increases stiffness of the structure which need to be flexible. The topology optimization technique is improved in the software so that compliant mechanisms without intersecting elements are obtained. The methodology that software uses and its capability will be shown on the examples of synthesis of the compliant gripper and the compliant displacement inverter.
From r-spin intersection numbers to Hodge integrals
Ding, Xiang-Mao; Li, Yuping [Institute of Applied Mathematics, Academy of Mathematics and Systems Science,Chinese Academy of Sciences,Beijing 100190, People’s Republic of (China); Meng, Lingxian [Institute of Applied Mathematics, Academy of Mathematics and Systems Science,Chinese Academy of Sciences,Beijing 100190, People’s Republic of (China); College of Mathematics and Information Science, Zhengzhou University of Light Industry,Zhengzhou 450002, People’s Republic of (China)
2016-01-04
Generalized Kontsevich Matrix Model (GKMM) with a certain given potential is the partition function of r-spin intersection numbers. We represent this GKMM in terms of fermions and expand it in terms of the Schur polynomials by boson-fermion correspondence, and link it with a Hurwitz partition function and a Hodge partition by operators in a (GL)-hat (∞) group. Then, from a W{sub 1+∞} constraint of the partition function of r-spin intersection numbers, we get a W{sub 1+∞} constraint for the Hodge partition function. The W{sub 1+∞} constraint completely determines the Schur polynomials expansion of the Hodge partition function.
The Standard Model from Stable Intersecting Brane World Orbifolds
Blumenhagen, R; Lüst, Dieter; Ott, T; Blumenhagen, Ralph; Kors, Boris; Lust, Dieter; Ott, Tassilo
2001-01-01
We analyze the perturbative stability of non-supersymmetric intersecting brane world models on tori. Besides the dilaton tadpole, a dynamical instability in the complex structure moduli space occurs at string disc level, which drives the background geometry to a degenerate limit. We show that in certain orbifold models this latter instability is absent as the relevant moduli are frozen. We construct explicit examples of such orbifold intersecting brane world models and discuss the phenomenological implications of a three generation Standard Model which descends naturally from an SU(5) GUT theory. It turns out that various phenomenological issues require the string scale to be at least of the order of the GUT scale. As a major difference compared to the Standard Model, some of the Yukawa couplings are excluded so that the standard electroweak Higgs mechanism with a fundamental Higgs scalar is not realized in this set-up.
Intersection of a Sure Ellipsoid and a Random Ellipsoid
Arjun K. Gupta
2012-07-01
Full Text Available Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif";} An Expression for the expected value of the intersection of a sure sphere and a random sphere has been derived by Laurent (1974. In the present paper we derive the expression for the expected intersection volume of a sure ellipsoid and a random ellipsoid
Sigma-model soliton intersections from exceptional calibrations
Portugues, R
2002-01-01
A first-order `BPS' equation is obtained for 1/8 supersymmetric intersections of soliton-membranes (lumps) of supersymmetric (4+1)-dimensional massless sigma models, and a special non-singular solution is found that preserves 1/4 supersymmetry. For 4-dimensional hyper-K\\"ahler target spaces ($HK_4$) the BPS equation is shown to be the low-energy limit of the equation for a Cayley-calibrated 4-surface in $\\bE^4\\times HK_4$. Similar first-order equations are found for stationary intersections of Q-lump-membranes of the massive sigma model, but now generic solutions preserve either 1/8 supersymmetry or no supersymmetry, depending on the time orientation.
The Standard Model from stable intersecting brane world orbifolds
Blumenhagen, Ralph E-mail: blumenha@physik.hu-berlin.de; Koers, Boris E-mail: koers@physik.hu-berlin.de; Luest, Dieter E-mail: luest@physik.hu-berlin.de; Ott, Tassilo E-mail: ott@physik.hu-berlin.de
2001-11-19
We analyze the perturbative stability of non-supersymmetric intersecting brane world models on tori. Besides the dilaton tadpole, a dynamical instability in the complex structure moduli space occurs at string disc level, which drives the background geometry to a degenerate limit. We show that in certain orbifold models this latter instability is absent as the relevant moduli are frozen. We construct explicit examples of such orbifold intersecting brane world models and discuss the phenomenological implications of a three generation Standard Model which descends naturally from an SU(5) GUT theory. It turns out that various phenomenological issues require the string scale to be at least of the order of the GUT scale. As a major difference compared to the Standard Model, some of the Yukawa couplings are excluded so that the standard electroweak Higgs mechanism with a fundamental Higgs scalar is not realized in this set-up.
Xue-jun Qiu; Rong-shu Zhu; Yan-qi Xu; Abulimiti Bumaliya; Song Zhang; Bing Zhang
2011-01-01
The ultrafast dynamics through conical intersections in 2,6-dimethylpyridine has been studied by femtosecond time-resolved photoelectron imaging coupled with time-resolved mass spectroscopy.Upon absorption of 266 nm pump laser,2,6-dimethylpyridine is excited to the S2 state with a ππ* character from So state.The time evolution of the parent ion signals consists of two exponential decays.One is a fast component on a timescale of 635 fs and the other is a slow component with a timescale of 4.37 ps.Time-dependent photoelectron angular distributions and energy-resolved photoelectron spectroscopy are extracted from time-resolved photoelectron imaging and provide the evolutive information of S2 state.In brief,the ultrafast component is a population transfer from S2 to S1 through the S2/S1 conical intersections,the slow component is attributed to simultaneous IC from the S2 state and the higher vibrational levels of S1 state to S0 state,which involves the coupling of S2/S0 and S1/S0 conical intersections.Additionally,the observed ultrafast S2→S1 transition occurs only with an 18% branching ratio.
Intersection Theory, Integrable Hierarchies and Topological Field Theory
Dijkgraaf, Robbert
1992-01-01
In these lecture notes we review the various relations between intersection theory on the moduli space of Riemann surfaces, integrable hierarchies of KdV type, matrix models, and topological quantum field theories. We explain in particular why matrix integrals of the type considered by Kontsevich naturally appear as tau-functions associated to minimal models. Our starting point is the extremely simple form of the string equation for the topological (p,1) models, where the so-called Baker-Akhi...
Cryptanalysis and improvement of a quantum private set intersection protocol
Cheng, Xiaogang; Guo, Ren; Chen, Yonghong
2017-02-01
A recent Quantum Private Set Intersection (QPSI) scheme is crypt-analyzed. The original claimed communication overhead is shown to be not accurate. And the original security definition is passive and not fair. To ensure fairness, a passive third party is introduced. It is also shown that unconditional fairness of QPSI protocol is impossible. Since otherwise, it would violate a well-known impossible quantum cryptography result.
Intersecting D-branes and black hole entropy
Behrndt, Klaus; Bergshoeff, Eric
1996-01-01
In four dimensions there are 4 different types of extremal Maxwell/scalar black holes characterized by a scalar coupling parameter a with a = 0, 1/âˆš3, 1, âˆš3. These black holes can be described as intersections of ten-dimensional non-singular Ramond-Ramond objects, i.e, D-branes, waves and Taub-N
Nonempty intersection theorems in topological spaces with applications
Min FANG; Nan-jing HUANG
2009-01-01
In this paper,we establish some new nonempty intersection theorems for generalized L-KKM mappings and prove some new fixed point theorems for set-valued mappings under suitable conditions in topological spaces.As applications,an existence theorem for an equilibrium problem with lower and upper bounds and two existence theorems for a quasi-equilibrium problem with lower and upper bounds are obtained in topological spaces.Our results generalize some known results in the literature.
Conical intersection dynamics of the primary photoisomerization event in vision.
Polli, Dario; Altoè, Piero; Weingart, Oliver; Spillane, Katelyn M; Manzoni, Cristian; Brida, Daniele; Tomasello, Gaia; Orlandi, Giorgio; Kukura, Philipp; Mathies, Richard A; Garavelli, Marco; Cerullo, Giulio
2010-09-23
Ever since the conversion of the 11-cis retinal chromophore to its all-trans form in rhodopsin was identified as the primary photochemical event in vision, experimentalists and theoreticians have tried to unravel the molecular details of this process. The high quantum yield of 0.65 (ref. 2), the production of the primary ground-state rhodopsin photoproduct within a mere 200 fs (refs 3-7), and the storage of considerable energy in the first stable bathorhodopsin intermediate all suggest an unusually fast and efficient photoactivated one-way reaction. Rhodopsin's unique reactivity is generally attributed to a conical intersection between the potential energy surfaces of the ground and excited electronic states enabling the efficient and ultrafast conversion of photon energy into chemical energy. But obtaining direct experimental evidence for the involvement of a conical intersection is challenging: the energy gap between the electronic states of the reacting molecule changes significantly over an ultrashort timescale, which calls for observational methods that combine high temporal resolution with a broad spectral observation window. Here we show that ultrafast optical spectroscopy with sub-20-fs time resolution and spectral coverage from the visible to the near-infrared allows us to follow the dynamics leading to the conical intersection in rhodopsin isomerization. We track coherent wave-packet motion from the photoexcited Franck-Condon region to the photoproduct by monitoring the loss of reactant emission and the subsequent appearance of photoproduct absorption, and find excellent agreement between the experimental observations and molecular dynamics calculations that involve a true electronic state crossing. Taken together, these findings constitute the most compelling evidence to date for the existence and importance of conical intersections in visual photochemistry.
SELF-INTERSECTION LOCAL TIME OF ADDITIVE LEVY PROCESS
钟玉泉; 胡迪鹤
2002-01-01
This article discusses the problem of existence of jointly continuous self-process X = {X(t), t ∈ RN+)} which has the decomposition X = X1 X2 ... Xv, eachThey prove that if Nrα＞ d(r - 1), then a jointly continuous local time of Z, i.e. theself-intersection local time of X, can be obtained.
Precision of Points Computed from Intersections of Lines or Planes
Cederholm, Jens Peter
2004-01-01
estimates the precision of the points. When using laser scanning a similar problem appears. A laser scanner captures a 3-D point cloud, not the points of real interest. The suggested method can be used to compute three-dimensional coordinates of the intersection of three planes estimated from the point...... cloud. The method can also be used to predict the precision of the points prior to a survey. An example is given....
Fuels Performance: Navigating the Intersection of Fuels and Combustion (Brochure)
2014-12-01
Researchers at the National Renewable Energy Laboratory (NREL), the only national laboratory dedicated 100% to renewable energy and energy efficiency, recognize that engine and infrastructure compatibility can make or break the impact of even the most promising fuel. NREL and its industry partners navigate the intersection of fuel chemistry, ignition kinetics, combustion, and emissions, with innovative approaches to engines and fuels that meet drivers' expectations, while minimizing petroleum use and GHGs.
Imploded test-chamber for an ISR intersection
1977-01-01
At the ISR intersection points the vacuum chambers had to be as "transparent" as possible, for the p-p collision product particles to reach the detectors with minimum hindrance. This meant the choice of a light, yet very strong, metal; minimum thickness; and corrugation for mechanical strength. The test-chamber seen here was made of 0.6 mm thick corrugated titanium, obviously not strong enough to withstand the atmospheric pressure.
Some phenomenology of intersecting D-brane models
Kane, Gordon L.; Kumar, Piyush; /Michigan U., MCTP; Lykken, Joseph D.; /Fermilab; Wang, Ting T.; /Michigan U., MCTP
2004-11-01
We present some phenomenology of a new class of intersecting D-brane models. Soft SUSY breaking terms for these models are calculated in the complex structure (u)-moduli dominant SUSY breaking approach (in type IIA). In this case, the dependence of the soft terms on the Yukawas and Wilson lines drops out. These soft terms have a different pattern compared to the usual heterotic string models. Phenomenological implications for dark matter are discussed.
Some Intersections and Identifications in Integral Group Rings
Ram Karan; Deepak Kumar
2002-05-01
Let be the integral group ring of a group and () its augmentation ideal. For a free group and a normal subgroup of , the intersection $I^{n+1}(F) \\cap I^n(R)$ is determined for all ≥ 1. The subgroups $F \\cap (1+ZFI(R)I(F)I(S))$ and $F \\cap (1+I(R)I^3(F))$ of are identified when and are arbitrary subgroups of .
Remote Sensing Image Registration with Line Segments and Their Intersections
Chengjin Lyu
2017-05-01
Full Text Available Image registration is a basic but essential step for remote sensing image processing, and finding stable features in multitemporal images is one of the most considerable challenges in the field. The main shape contours of artificial objects (e.g., roads, buildings, farmlands, and airports can be generally described as a group of line segments, which are stable features, even in images with evident background changes (e.g., images taken before and after a disaster. In this study, a registration method that uses line segments and their intersections is proposed for multitemporal remote sensing images. First, line segments are extracted in image pyramids to unify the scales of the reference image and the test image. Then, a line descriptor based on the gradient distribution of local areas is constructed, and the segments are matched in image pyramids. Lastly, triplets of intersections of matching lines are selected to estimate affine transformation between two images. Additional corresponding intersections are provided based on the estimated transformation, and an iterative process is adopted to remove outliers. The performance of the proposed method is tested on a variety of optical remote sensing image pairs, including synthetic and real data. Compared with existing methods, our method can provide more accurate registration results, even in images with significant background changes.
Complete intersections K-theory and Chern classes
Mandal, S S
1996-01-01
Throughout this abstruct A will denote a noetherian commutative ring of dimension n. The paper has two parts. Among the interesting results in Part-1 are the following: 1) {\\it suppose that f_1, f_2, \\ldots, f_r (with r \\leq n) is a regular sequence in A and suppose Q is a projective A-module of rank r that maps onto the ideal (f_1, f_2, \\ldots, f_{r-1},f_r^{(r-1)!}). Then [Q]=[Q_0 \\oplus A] in K_0(A) for some projective A-module~Q_0 of rank r-1.} 2) The set F_0K_0(A) = \\{[A/I] \\in K_0(A): I~ is~ a~ locally~ complete ~intersection~ ideal~ in~ A~ of~ height~n \\} is a {\\it subgroup} of K_0(A). We also show that if A is a reduced affine algebra over a field k then F_0K_0(A) {\\it is indeed the Zero Cycle Subgroup of} K_0(A) {\\it that is generated by smooth maximal ideals} \\Cal M {\\it of height} n. 3){\\it let A be such that whenever I is a locally complete intersection ideal of height n with [A/I]=0 then I is the image of a projective A-module of rank n. Then for any locally complete intersection ideal J of height...
Droplets coalescence at microchannel intersection chambers with different shapes
Liu, Zhaomiao; Wang, Xiang; Cao, Rentuo; Pang, Yan
2016-11-01
The influence of microchannel intersection chamber shape on droplets coalescence process is investigated in this study. Three kinds of chamber shapes (half-round, triangle and camber) are designed to realize head-on droplets coalescence. The coalescence processes are visualized with high-speed camera system and the internal flow patterns are resolved with micro-PIV system. Experimental analyses on droplets coalescence position, coalescence time and the critical conditions are discussed. Both direct coalescence and late coalescence can be observed in the camber junction while only the late coalescence is present for the half-round and the triangle junction. The critical capillary number Ca* varies for different working systems or intersection shapes. Ca* in the camber junction is larger than that in the other two junctions for each working system and it decreases with the increase of the viscosity ratios for each intersection shape. Moreover, the characteristics of the velocity fields for different coalescence cases are analyzed for in-depth understanding of the process. The authors do appreciate the financial support of No.11572013 of National Nature Scicence Funding of China.
Conical intersection seams in polyenes derived from their chemical composition
Nenov, Artur; Vivie-Riedle, Regina de [Department Chemie, Ludwig-Maximilians-Univerisitaet, Muenchen Butenandtstr. 11, 81377 Muenchen (Germany)
2012-08-21
The knowledge of conical intersection seams is important to predict and explain the outcome of ultrafast reactions in photochemistry and photobiology. They define the energetic low-lying reachable regions that allow for the ultrafast non-radiative transitions. In complex molecules it is not straightforward to locate them. We present a systematic approach to predict conical intersection seams in multifunctionalized polyenes and their sensitivity to substituent effects. Included are seams that facilitate the photoreaction of interest as well as seams that open competing loss channels. The method is based on the extended two-electron two-orbital method [A. Nenov and R. de Vivie-Riedle, J. Chem. Phys. 135, 034304 (2011)]. It allows to extract the low-lying regions for non-radiative transitions, which are then divided into small linear segments. Rules of thumb are introduced to find the support points for these segments, which are then used in a linear interpolation scheme for a first estimation of the intersection seams. Quantum chemical optimization of the linear interpolated structures yields the final energetic position. We demonstrate our method for the example of the electrocyclic isomerization of trifluoromethyl-pyrrolylfulgide.
Conical intersection seams in polyenes derived from their chemical composition
Nenov, Artur; de Vivie-Riedle, Regina
2012-08-01
The knowledge of conical intersection seams is important to predict and explain the outcome of ultrafast reactions in photochemistry and photobiology. They define the energetic low-lying reachable regions that allow for the ultrafast non-radiative transitions. In complex molecules it is not straightforward to locate them. We present a systematic approach to predict conical intersection seams in multifunctionalized polyenes and their sensitivity to substituent effects. Included are seams that facilitate the photoreaction of interest as well as seams that open competing loss channels. The method is based on the extended two-electron two-orbital method [A. Nenov and R. de Vivie-Riedle, J. Chem. Phys. 135, 034304 (2011)], 10.1063/1.3608924. It allows to extract the low-lying regions for non-radiative transitions, which are then divided into small linear segments. Rules of thumb are introduced to find the support points for these segments, which are then used in a linear interpolation scheme for a first estimation of the intersection seams. Quantum chemical optimization of the linear interpolated structures yields the final energetic position. We demonstrate our method for the example of the electrocyclic isomerization of trifluoromethyl-pyrrolylfulgide.
Caregiver Well-Being: Intersections of Relationship and Gender.
Chappell, Neena L; Dujela, Carren; Smith, André
2015-08-01
We know much about caregiving women compared with caregiving men and caregiving spouses compared with caregiving adult children. We know less about the intersections of relationship and gender. This article explores this intersection through the well-being (burden and self-esteem) of caregivers to family members with dementia. Throughout British Columbia, Canada, 873 caregivers were interviewed in person for on average, over 1½ hours. The results reveal that daughters experience the highest burden but also the highest self-esteem, suggesting the role is less salient for their self-identities. Wives emerge as the most vulnerable of the four groups when both burden and self-esteem are considered. The data confirm the usefulness of the intersectionality framework for understanding co-occupancy of more than one status and indicate that positive cognitive well-being and negative affective well-being can be differentially related. Multivariate analyses confirm the importance of caregiver, not patient, characteristics for burden and self-esteem. © The Author(s) 2014.
Traffic light detection and intersection crossing using mobile computer vision
Grewei, Lynne; Lagali, Christopher
2017-05-01
The solution for Intersection Detection and Crossing to support the development of blindBike an assisted biking system for the visually impaired is discussed. Traffic light detection and intersection crossing are key needs in the task of biking. These problems are tackled through the use of mobile computer vision, in the form of a mobile application on an Android phone. This research builds on previous Traffic Light detection algorithms with a focus on efficiency and compatibility on a resource-limited platform. Light detection is achieved through blob detection algorithms utilizing training data to detect patterns of Red, Green and Yellow in complex real world scenarios where multiple lights may be present. Also, issues of obscurity and scale are addressed. Safe Intersection crossing in blindBike is also discussed. This module takes a conservative "assistive" technology approach. To achieve this blindBike use's not only the Android device but, an external bike cadence Bluetooth/Ant enabled sensor. Real world testing results are given and future work is discussed.
Scanlon, John M; Sherony, Rini; Gabler, Hampton C
2016-09-01
Intersection crashes resulted in over 5,000 fatalities in the United States in 2014. Intersection Advanced Driver Assistance Systems (I-ADAS) are active safety systems that seek to help drivers safely traverse intersections. I-ADAS uses onboard sensors to detect oncoming vehicles and, in the event of an imminent crash, can either alert the driver or take autonomous evasive action. The objective of this study was to develop and evaluate a predictive model for detecting whether a stop sign violation was imminent. Passenger vehicle intersection approaches were extracted from a data set of typical driver behavior (100-Car Naturalistic Driving Study) and violations (event data recorders downloaded from real-world crashes) and were assigned weighting factors based on real-world frequency. A k-fold cross-validation procedure was then used to develop and evaluate 3 hypothetical stop sign warning algorithms (i.e., early, intermediate, and delayed) for detecting an impending violation during the intersection approach. Violation detection models were developed using logistic regression models that evaluate likelihood of a violation at various locations along the intersection approach. Two potential indicators of driver intent to stop-that is, required deceleration parameter (RDP) and brake application-were used to develop the predictive models. The earliest violation detection opportunity was then evaluated for each detection algorithm in order to (1) evaluate the violation detection accuracy and (2) compare braking demand versus maximum braking capabilities. A total of 38 violating and 658 nonviolating approaches were used in the analysis. All 3 algorithms were able to detect a violation at some point during the intersection approach. The early detection algorithm, as designed, was able to detect violations earlier than all other algorithms during the intersection approach but gave false alarms for 22.3% of approaches. In contrast, the delayed detection algorithm sacrificed
Intersection Theory, Integrable Hierarchies and Topological Field Theory
Dijkgraaf, R
1992-01-01
In these lecture notes we review the various relations between intersection theory on the moduli space of Riemann surfaces, integrable hierarchies of KdV type, matrix models, and topological quantum field theories. We explain in particular why matrix integrals of the type considered by Kontsevich naturally appear as tau-functions associated to minimal models. Our starting point is the extremely simple form of the string equation for the topological (p,1) models, where the so-called Baker-Akhiezer function is given by a (generalized) Airy function.
Unpacking Pat Parker: Intersections and Revolutions in "Movement in Black".
Washburn, Amy
2015-01-01
This article explores Pat Parker's poem "Movement in Black." It examines the ways in which she emblematizes intersectionality and simultaneity as forms of revolution in struggles of self and society. It begins with a theoretical and historical apparatus to contextualize Parker as an artist and activist. Then it offers a literary analysis of the poem, focusing on themes of time and space, marginalization and movement, difference and power, visibility and invisibility, and history and memory. It argues that Parker uses autobiographical writing to fuse personal and political sites of resistance.
Brane Intersections in the Presence of a Worldvolume Electric Field
Bhattacharya, R; Bhattacharyya, Rajsekhar; Douari, Jamila
2005-01-01
The study of brane intersections has provided important insights into a possible non-commutative structure of spacetime geometry. In this paper we focus on the D1$\\bot$D3 system. We compare the D1 and D3 descriptions of the interesection and search for non-static solutions of the D3$\\bot$D1 funnel equations in the presence of a worldvolume electric field. We find that the D1 and D3 descriptions do not agree. We find time dependent solutions that are a natural generalization of those found without the electric field.
Stability of distributed MPC in an intersection scenario
Sprodowski, T.; Pannek, J.
2015-11-01
The research topic of autonomous cars and the communication among them has attained much attention in the last years and is developing quickly. Among others, this research area spans fields such as image recognition, mathematical control theory, communication networks, and sensor fusion. We consider an intersection scenario where we divide the shared road space in different cells. These cells form a grid. The cars are modelled as an autonomous multi-agent system based on the Distributed Model Predictive Control algorithm (DMPC). We prove that the overall system reaches stability using Optimal Control for each multi-agent and demonstrate that by numerical results.
Some Problems of Unlikely Intersections in Arithmetic and Geometry
Zannier, Umberto
2012-01-01
This book considers the so-called Unlikely Intersections, a topic that embraces well-known issues, such as Lang's and Manin-Mumford's, concerning torsion points in subvarieties of tori or abelian varieties. More generally, the book considers algebraic subgroups that meet a given subvariety in a set of unlikely dimension. The book is an expansion of the Hermann Weyl Lectures delivered by Umberto Zannier at the Institute for Advanced Study in Princeton in May 2010. The book consists of four chapters and seven brief appendixes, the last six by David Masser. The first chapter considers multipli
Intersecting D 3 -D3 ' -brane system at finite temperature
Cottrell, William; Hanson, James; Hashimoto, Akikazu; Loveridge, Andrew; Pettengill, Duncan
2017-02-01
We analyze the dynamics of the intersecting D 3 -D3 ' -brane system overlapping in 1 +1 dimensions, in a holographic treatment where N D3 branes are manifested as anti-de Sitter Schwartzschild geometry, and the D3 ' brane is treated as a probe. We extract the thermodynamic equation of state from the set of embedding solutions, and analyze the stability at the perturbative and the nonperturbative level. We review a systematic procedure to resolve local instabilities and multivaluedness in the equations of state based on classic ideas of convexity in the microcanonical ensemble. We then identify a runaway behavior which was not noticed previously for this system.
Wide-angle spectrometer at intersection I-2
CERN PhotoLab
1973-01-01
The members of the British-Scandinavian ISR Collaboration "manning the rails" of the wide-angle spectrometer at intersection I-2, whose vacuum chamber is visible to theleft. The equipment of this high-momentum version of experiment R203 consists of scintillation counter hodoscopes, wire spark chambers, and spherical high-pressure threshold Cerenkov counters before and after an analysing magnet. The equipment is mounted on a movable platform. The smaller magnet suspended above the spectrometer measures the momentum of cosmic rays.
Novel Intersection Type Recognition for Autonomous Vehicles Using a Multi-Layer Laser Scanner.
An, Jhonghyun; Choi, Baehoon; Sim, Kwee-Bo; Kim, Euntai
2016-07-20
There are several types of intersections such as merge-roads, diverge-roads, plus-shape intersections and two types of T-shape junctions in urban roads. When an autonomous vehicle encounters new intersections, it is crucial to recognize the types of intersections for safe navigation. In this paper, a novel intersection type recognition method is proposed for an autonomous vehicle using a multi-layer laser scanner. The proposed method consists of two steps: (1) static local coordinate occupancy grid map (SLOGM) building and (2) intersection classification. In the first step, the SLOGM is built relative to the local coordinate using the dynamic binary Bayes filter. In the second step, the SLOGM is used as an attribute for the classification. The proposed method is applied to a real-world environment and its validity is demonstrated through experimentation.
Finite Temperature Corrections to Tachyon Mass in Intersecting D-Branes
Sethi, Varun; Sarkar, Swarnendu
2016-01-01
We continue with the analysis of finite temperature corrections to the Tachyon mass in intersecting branes which was initiated in arxiv:1403.0389. In this paper we extend the computation to the case of intersecting D3-branes by considering a setup of two intersecting branes in flat-space background. A holographic model dual to BCS superconductor consisting of intersecting D8-branes in D4-brane background was proposed in arxiv:1104.2843. The background considered here is a simplified configuration of this dual model. We compute the one-loop Tachyon amplitude in the Yang-Mills approximation and show that the result is finite. Analyzing the amplitudes further we numerically compute the transition temperature at which the Tachyon becomes massless. The analytic expressions for the one-loop amplitudes obtained here reduce to those for intersecting D1-branes obtained in arxiv:1403.0389 as well as those for intersecting D2-branes.
Characteristics of Traffic Flow at Nonsignalized T-Shaped Intersection with U-Turn Movements
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.
Characteristics of traffic flow at nonsignalized T-shaped intersection with U-turn movements.
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.
Novel Intersection Type Recognition for Autonomous Vehicles Using a Multi-Layer Laser Scanner
Jhonghyun An
2016-07-01
Full Text Available There are several types of intersections such as merge-roads, diverge-roads, plus-shape intersections and two types of T-shape junctions in urban roads. When an autonomous vehicle encounters new intersections, it is crucial to recognize the types of intersections for safe navigation. In this paper, a novel intersection type recognition method is proposed for an autonomous vehicle using a multi-layer laser scanner. The proposed method consists of two steps: (1 static local coordinate occupancy grid map (SLOGM building and (2 intersection classification. In the first step, the SLOGM is built relative to the local coordinate using the dynamic binary Bayes filter. In the second step, the SLOGM is used as an attribute for the classification. The proposed method is applied to a real-world environment and its validity is demonstrated through experimentation.
Coloring intersection graphs of x-monotone curves in the plane
Suk, Andrew
2012-01-01
A class of graphs G is \\chi-bounded if the chromatic number of the graphs in G is bounded by some function of their clique number. We show that the class of intersection graphs of simple x-monotone curves in the plane intersecting a vertical line is \\chi-bounded. As a corollary, the class of intersection graphs of rays in the plane is \\chi-bounded.
Lund Hansen, Dennis; Lauritsen, Jens M
2010-01-01
accidents treated at three hospitals for a region covering roughly 0.5 mio persons were recorded routinely and subsequently geo-coded to exact location. For 8191 injured persons the traffic accident occurred in one of 2157 road intersections. In total the county holds 56.994 intersections. Hot spots were...... of intersections considered as a black spot. GIS methods must take this into consideration....
The intersection numbers of the p-spin curves from random matrix theory
Brezin, E
2012-01-01
The intersection numbers of p-spin curves are computed through correlation functions of Gaussian ensembles of random matrices in an external matrix source. The p-dependence of intersection numbers is determined as polynomial in p; the large p behavior is also considered. The analytic continuation of intersection numbers to negative values of p is discussed in relation to SL(2,R)/U(1) black hole sigma model.
The intersection numbers of the p-spin curves from random matrix theory
Brézin, E.; Hikami, S.
2013-02-01
The intersection numbers of p-spin curves are computed through correlation functions of Gaussian ensembles of random matrices in an external matrix source. The p-dependence of intersection numbers is determined as polynomial in p; the large p behavior is also considered. The analytic continuation of intersection numbers to negative values of p is discussed in relation to SL(2,R)/U(1) black hole sigma model.
Diversity in the Tail of the Intersecting Brane Landscape
Rosenhaus, Vladimir
2009-01-01
Techniques are developed for exploring the complete space of intersecting brane models on an orientifold. The classification of all solutions for the widely-studied T^6/Z_2 x Z_2 orientifold is made possible by computing all combinations of branes with negative tadpole contributions. This provides the necessary information to systematically and efficiently identify all models in this class with specific characteristics. In particular, all ways in which a desired group G can be realized by a system of intersecting branes can be enumerated in polynomial time. We identify all distinct brane realizations of the gauge groups SU(3) x SU(2) and SU(3) x SU(2) x U(1) which can be embedded in any model which is compatible with the tadpole and SUSY constraints. We compute the distribution of the number of generations of "quarks" and find that 3 is neither suppressed nor particularly enhanced compared to other odd generation numbers. The overall distribution of models is found to have a long tail. Despite disproportionat...
The Wicked Problem of the Intersection between Supervision and Evaluation
Ian M. METTE
2017-03-01
Full Text Available The purpose of this research was to explore how principals in eight high-functioning elementary schools in one American school district balanced teacher supervision and evaluation in their role as an instructional leader. Using the theoretical framework of ‘wicked problems’, to unpack the circular used to problematize teacher supervision and evaluation, the findings analyse how elementary principals in these eight buildings acknowledge the tensions and conflicts between supervision and evaluation, specifically as they relate to improving teacher instruction. Specifically, the results of this study highlight not only the differences between supervision and evaluation, but also the intersection between the two functions, as well as how high-performing elementary school principals serve as an instructional coach rather than a manager of teachers. While the two functions of supervision and evaluation are inherently different, it is the acknowledgement of the intersection between the two functions that can allow building principals to progress as instructional coaches who can better develop human resources and create higher-functioning school systems. Overall, this study points toward the importance of elementary principals having the instructional leadership skills to differentiate supervision and professional development need for teachers, which in turn influences the evaluation of a teacher is in her/his respective career.
Period Integrals of CY and General Type Complete Intersections
Lian, Bong H
2011-01-01
We develop a global Poincar\\'e residue formula to study period integrals of families of complex manifolds. For any compact complex manifold $X$ equipped with a linear system $V^*$ of generically smooth CY hypersurfaces, the formula expresses period integrals in terms of a canonical global meromorphic top form on $X$. Two important ingredients of our construction are the notion of a CY principal bundle, and a classification of such rank one bundles. We also generalize our construction to CY and general type complete intersections. When $X$ is an algebraic manifold having a sufficiently large automorphism group $G$ and $V^*$ is a linear representation of $G$, we construct a holonomic D-module that governs the period integrals. The construction is based in part on the theory of tautological systems we have developed in the paper \\cite{LSY1}, joint with R. Song. The approach allows us to explicitly describe a Picard-Fuchs type system for complete intersection varieties of general types, as well as CY, in any Fano...
Remote infrared signage evaluation for transit stations and intersections.
Crandall, W; Brabyn, J; Bentzen, B L; Myers, L
1999-10-01
Opportunities for education and employment depend upon effective and independent travel. For mainstream society, this is accomplished to a large extent by printed signs. People who are print disabled, visually impaired, or totally blind are at a disadvantage because they do not have access to signage. Remote infrared signage, such as the Talking Signs (TS) system, provides a solution to this need by labeling the environment for distant viewing. The system uses a transmitting "sign" and a hand-held receiver to tell people about their surroundings. In a seamless infrared signage environment, a visually impaired traveler could: walk safely across an intersection to an ATM or fare machine, from fare machine to bus stop, from bus stop to bus; from bus to building, from building to elevator, from elevator to office, from office to restroom, and so forth. This paper focuses on two problems that are among the most challenging and dangerous faced by blind travelers: negotiating complex transit stations and controlled intersections. We report on human factors studies of TS in these critical tasks, examining such issues as how much training is needed to use the system, its impact on performance and safety, benefits for different population subgroups and user opinions of its value. Results indicate that blind people can quickly and easily learn to use remote infrared signage effectively, and that its use improves travel safety, efficiency, and independence.
Intersection local times, loop soups and permanental Wick powers
Jan, Yves Le; Rosen, Jay
2017-01-01
Several stochastic processes related to transient Lévy processes with potential densities u(x,y)=u(y-x), that need not be symmetric nor bounded on the diagonal, are defined and studied. They are real valued processes on a space of measures \\mathcal{V} endowed with a metric d. Sufficient conditions are obtained for the continuity of these processes on (\\mathcal{V},d). The processes include n-fold self-intersection local times of transient Lévy processes and permanental chaoses, which are `loop soup n-fold self-intersection local times' constructed from the loop soup of the Lévy process. Loop soups are also used to define permanental Wick powers, which generalizes standard Wick powers, a class of n-th order Gaussian chaoses. Dynkin type isomorphism theorems are obtained that relate the various processes. Poisson chaos processes are defined and permanental Wick powers are shown to have a Poisson chaos decomposition. Additional properties of Poisson chaos processes are studied and a martingale extension is obt...
Intersecting Black Attractors in 8D N=1 Supergravity
Laamara, R Ahl; Hassani, F Z; Saidi, E H; Soumail, A A
2010-01-01
We study intersecting extremal black attractors in non chiral 8D N=1 supergravity with moduli space ((SO(2,N))/(SO(2)\\times SO(N)))\\times SO(1,1) and work out explicitly the attractor mechanism for various black p-brane configurations with the typical near horizon geometries AdS_{p+2} \\times S^{m} \\times T^{6-p-m}. We also give the classification of the solutions of the attractor equations in terms of the SO(N-k) subgroups of SO(2)\\times SO(N) symmetry of the moduli space as well as their interpretations in terms of both heterotic string on 2-torus and its type IIA dual. Other features such as non trivial SO(1,7) central charges Z_{{\\mu}_1...{\\mu}_{p}} in 8D N=1 supergravity and their connections to p-form gauge fields are also given. Key Words: 8D Supergravity, Superstring compactifications, Attractor Mechanism, Intersecting Attractors. PACS numbers: 04.70.-s, 11.25.-w, 04.65.+e, 04.70.-s, 04.50.+h, 04.70.Dy
Ultrafast charge transfer via a conical intersection in dimethylaminobenzonitrile.
Fuss, Werner; Pushpa, Kumbil Kuttan; Rettig, Wolfgang; Schmid, Wolfram E; Trushin, Sergei A
2002-04-01
The L(a)-like S2 state (2A) of 4-(dimethylamino)benzonitrile was pumped at 267 nm in the gas phase at 130 degrees C. Nonresonant multiphoton ionization at 800 nm with mass-selective detection then probed the subsequent processes. Whereas ionization at the Franck-Condon geometry only gave rise to the parent ion, fragmentation increased on motion towards the charge-transfer (CT) state. This useful difference is ascribed to a geometry-dependent resonance in the ion. The time constants found are interpreted by ultrafast (approximately 68 fs) relaxation through a conical intersection to both the CT and the L(b)-type S1 state (1B). Then the population equilibrates between these two states within 1 ps. From there the molecule relaxes within 90 ps to a lower excited state which can only be a triplet state (T(n)) and then decomposes within 300 ps. Previous experiments either investigated only 1B --> CT relaxation-which does not take place in the gas phase or nonpolar solvents for energetic reasons--or, starting from S2 excitation, typically had insufficient time resolution (>1 ps) to detect the temporary charge transfer. Only recently temporary population of the CT state was found in a nonpolar solvent (Kwok et al., J. Phys. Chem. A. 2000, 104, 4188), a result fully consistent with our mechanism. We also show that S2 --> S1 relaxation does not occur vertically but involves an intermediate strong geometrical distortion, passing through a conical intersection.
Boolean operations of STL models based on edge-facet intersection
无
2007-01-01
For the data processing of the Rapid Prototyping Manufacturing, Boolean operation can offer a versatile tool for editing or modifying the STL model, adding the artificial construction, and creating the complex assistant support structure to meet the special technical requests. The topological structure of STL models was built firstly in order to obtain the neighborhood relationship among the triangular facets. The intersection test between every edge of one solid and every facet of another solid Was taken to get the intersection points. According to the matching relationship of the triangle index recorded in the data structure of the intersection points, the intersection segments array and the intersection loop were traced out. Each intersected triangle was subdivided by the Constrained Delaunay Triangulations. The intersected surfaces were divided into several surface patches along the intersection loops. The inclusion prediction between the surface patch and the other solid was taken by testing whether the candidate point Was inside or outside the solid region of the slice. Detecting the loops for determination of the valid intersection lines greatly increases the efficiency and the reliability of the process.
A method of dealing polygon's self-intersection contour in SLA
GAO Yong-qiang; MO Jian-hua; HUANG Shu-huai
2007-01-01
The contour of the slices of SLA parts is composed of a great deal of small lines. When offsetting the contour to compensate for the radius of laser spot, many self-intersection contours come into being, which decrease the precision of formed parts. A new lemma to judge the local self-intersection contour and the global self-intersection contour separately is put forward, according to which self-intersection contour can be removed reliably. Meanwhile, a new beam offsetting algorithm for SLA parts is described, which brings about good results in the practical manufacturing process.
Complex Road Intersection Modelling Based on Low-Frequency GPS Track Data
Huang, J.; Deng, M.; Zhang, Y.; Liu, H.
2017-09-01
It is widely accepted that digital map becomes an indispensable guide for human daily traveling. Traditional road network maps are produced in the time-consuming and labour-intensive ways, such as digitizing printed maps and extraction from remote sensing images. At present, a large number of GPS trajectory data collected by floating vehicles makes it a reality to extract high-detailed and up-to-date road network information. Road intersections are often accident-prone areas and very critical to route planning and the connectivity of road networks is mainly determined by the topological geometry of road intersections. A few studies paid attention on detecting complex road intersections and mining the attached traffic information (e.g., connectivity, topology and turning restriction) from massive GPS traces. To the authors' knowledge, recent studies mainly used high frequency (1 s sampling rate) trajectory data to detect the crossroads regions or extract rough intersection models. It is still difficult to make use of low frequency (20-100 s) and easily available trajectory data to modelling complex road intersections geometrically and semantically. The paper thus attempts to construct precise models for complex road intersection by using low frequency GPS traces. We propose to firstly extract the complex road intersections by a LCSS-based (Longest Common Subsequence) trajectory clustering method, then delineate the geometry shapes of complex road intersections by a K-segment principle curve algorithm, and finally infer the traffic constraint rules inside the complex intersections.
HIV-1 intersection with CD4 T cell vesicle exocytosis: intercellular communication goes viral
Helena eSoares
2014-09-01
Full Text Available In cells of the immune system the secretion of extracellular vesicles is modulated through cellular activation. In particular, T cell activation is achieved through cell-cell contacts with antigen presenting cells and the consequent formation of a specialized signaling junction called the immunological synapse. Recent works on CD4 T cells have elucidated that cognate antigen recognition by the T cell receptor (TCR engages two distinct exocytic events. The first, involves the exocytic targeting of signaling molecules at the synaptic membrane and drives the functional architecture of the immunological synapse. The second, enlists the extracellular secretion of the TCR itself, once the functional architecture of the immunological synapse is accomplished. HIV-1, a human lymphotropic virus, has evolved sophisticated mechanisms to co-opt CD4 T cell physiology. Notably, it has become apparent that HIV-1 intersects the regulated secretory system of CD4 T cells in order to bud from the plasma membrane of the infected cell and to promote bystander cell death. Here, I review the relevance of CD4 vesicle exocytosis to immune regulation and to HIV-1 pathogenesis and discuss their potential therapeutic applications.
Wu, Yu; Cheng, Tianhai; Zheng, Lijuan; Chen, Hao; Xu, Hui
2015-05-01
The optical properties of light absorbing soot aerosols generally change through interactions with weakly absorbing particles, resulting in complex mixing states, and have been highlighted as a major uncertainty in assessing their radiative forcing and climatic impact. The single scattering properties of soot aggregates partially embedded in the host sulfate particle (semi-embedded soot-containing mixtures) are investigated for two kinds of morphologies with intersecting and non-intersecting surfaces. The surfaces cannot be overlapped in the non-intersecting surface morphology, while the intersecting surface morphology is unconstrained. Based on the modified diffusion limited aggregation (DLA) algorithm, the models with non-intersecting surfaces are simulated and applied for the single scattering calculations of semi-embedded soot-containing mixtures using the superposition T-matrix (STM) method. For comparison, the models with intersecting surfaces are simulated with the same morphological parameters, but some soot monomers are intersected by the host sphere. Due to the limitation of current STM method, the optical properties of these models with intersecting surfaces are calculated using the discrete dipole approximation (DDA) method. The soot volume fractions outside sulfate host (Fs,out) are introduced and applied to characterize the mixing states of the soot-containing aerosols. These simulations show that the absorption cross-sections of those internally, deeply, half and slightly embedded mixed soot particles (Fs,out = 0.0, 0.2, 0.5, 0.8) are ~105%, ~65%, ~43% and ~14% larger than the semi-external mixtures (Fs,out = 1.0), respectively. The results also indicate that the differences of extinction cross-sections, single scattering albedo (SSA) and asymmetry parameter (ASY) between simulations with intersecting and non-intersecting surfaces are small (infrared wavelengths, the relative deviations of absorption cross-sections between these different
Quistberg, D. Alex; Howard, Eric J.; Ebel, Beth E.; Moudon, Anne V.; Saelens, Brian E.; Hurvitz, Philip M.; Curtin, James E.; Rivara, Frederick P.
2015-01-01
Walking is a popular form of physical activity associated with clear health benefits. Promoting safe walking for pedestrians requires evaluating the risk of pedestrian-motor vehicle collisions at specific roadway locations in order to identify where road improvements and other interventions may be needed. The objective of this analysis was to estimate the risk of pedestrian collisions at intersections and mid-blocks in Seattle, WA. The study used 2007-2013 pedestrian-motor vehicle collision data from police reports and detailed characteristics of the microenvironment and macroenvironment at intersection and mid-block locations. The primary outcome was the number of pedestrian-motor vehicle collisions over time at each location (incident rate ratio [IRR] and 95% confidence interval [95% CI]). Multilevel mixed effects Poisson models accounted for correlation within and between locations and census blocks over time. Analysis accounted for pedestrian and vehicle activity (e.g., residential density and road classification). In the final multivariable model, intersections with 4 segments or 5 or more segments had higher pedestrian collision rates compared to mid-blocks. Non-residential roads had significantly higher rates than residential roads, with principal arterials having the highest collision rate. The pedestrian collision rate was higher by 9% per 10 feet of street width. Locations with traffic signals had twice the collision rate of locations without a signal and those with marked crosswalks also had a higher rate. Locations with a marked crosswalk also had higher risk of collision. Locations with a one-way road or those with signs encouraging motorists to cede the right-of-way to pedestrians had fewer pedestrian collisions. Collision rates were higher in locations that encourage greater pedestrian activity (more bus use, more fast food restaurants, higher employment, residential, and population densities). Locations with higher intersection density had a lower
LI Ying-feng; SHI Zhong-ke; ZHOU Zhi-na
2009-01-01
We made an on-site investigation about pedestrian violation of traffic violation decision and the impact of the number of pedestrians in colony that the probability of pedestrian violation rose with the waiting time for simulating mixed vehicles and pedestrians and used the on-site investigation data to validate the model.When traffic volume is light,the error between the simulated values and the measured ones is 2.47%.When traffic volume is heavy,the error is 3.38%.
Supersymmetric gauge theories, intersecting branes and free fermions
Dijkgraaf, Robbert; Hollands, Lotte; Sułkowski, Piotr; Vafa, Cumrun
2008-02-01
We show that various holomorphic quantities in supersymmetric gauge theories can be conveniently computed by configurations of D4-branes and D6-branes. These D-branes intersect along a Riemann surface that is described by a holomorphic curve in a complex surface. The resulting I-brane carries two-dimensional chiral fermions on its world-volume. This system can be mapped directly to the topological string on a large class of non-compact Calabi-Yau manifolds. Inclusion of the string coupling constant corresponds to turning on a constant B-field on the complex surface, which makes this space non-commutative. Including all string loop corrections the free fermion theory is elegantly formulated in terms of holonomic D-modules that replace the classical holomorphic curve in the quantum case.
Supersymmetric Gauge Theories, Intersecting Branes and Free Fermions
Dijkgraaf, Robbert; Sulkowski, Piotr; Vafa, Cumrun
2008-01-01
We show that various holomorphic quantities in supersymmetric gauge theories can be conveniently computed by configurations of D4-branes and D6-branes. These D-branes intersect along a Riemann surface that is described by a holomorphic curve in a complex surface. The resulting I-brane carries two-dimensional chiral fermions on its world-volume. This system can be mapped directly to the topological string on a large class of non-compact Calabi-Yau manifolds. Inclusion of the string coupling constant corresponds to turning on a constant B-field on the complex surface, which makes this space non-commutative. Including all string loop corrections the free fermion theory is elegantly formulated in terms of holonomic D-modules that replace the classical holomorphic curve in the quantum case.
Structures du cube et fibres d'intersection
Ducrot, F
1997-01-01
We define the notion of a hypercube structure on a functor between two strictly commutative Picard categories which generalizes the notion of a cube structure on a $G_m$-torsor over an abelian scheme. We use this notion to define the intersection bundle of $n+1$ line bundles on a relative scheme $X/S$ of relative dimension $n$ and to construct an additive structure on the functor $I_{X/S}:PIC(X/S)^{n+1}\\F PIC(S)$. Finally, we study a section of $I_{X/S}(L_1,...,L_{n+1})$ which generalizes the resultant of $n+1$ polynomials in $n$ variables and we interprete some classical formulas with this formalism.
Supersymmetric Composite Models on Intersecting D-branes
Kitazawa, N
2004-01-01
We construct supersymmetric composite models of quarks and leptons from type IIA T^6/(Z_2 x Z_2) orientifolds with intersecting D6-branes. In case of T^6 = T^2 x T^2 x T^2 with no tilted T^2, a composite model of the supersymmetric SU(5) grand unified theory with three generations is constructed. In case of that one T^2 is tilted, a composite model with SU(3)_c x SU(2)_L x U(1)_Y gauge symmetry with three generations is constructed. These models are not realistic, but contain fewer additional exotic particles and U(1) gauge symmetries due to the introduction of the compositeness of quarks and leptons. The mu-term of Higgs fields can be naturally generated through the exponentially suppressed Yukawa interaction among "preons".
Holography, brane intersections and six-dimensional SCFTs
Bobev, Nikolay; Dibitetto, Giuseppe; Gautason, Friðrik Freyr; Truijen, Brecht
2017-02-01
We study supersymmetric intersections of NS5-, D6- and D8-branes in type IIA string theory. We focus on the supergravity description of this system and identify a "near horizon" limit in which we recover the recently classified supersymmetric seven-dimensional AdS solutions of massive type IIA supergravity. Using a consistent truncation to seven-dimensional gauged supergravity we construct a universal supersymmetric deformation of these AdS vacua. In the holographic dual six-dimensional (1,0) superconformal field theory this deformation describes a universal RG flow on the tensor branch of the vacuum moduli space triggered by a vacuum expectation value for a protected scalar operator of dimension four.
Automatic recognition of intersecting features of freeform sheet metal parts
Chun-jie ZHANG; Xiong-hui ZHOU; Cong-xin LI
2009-01-01
This paper presents an approach for recognizing both isolated and intersecting geometric features of freeform surface models of parts, for the purpose of automating the process planning of sheet metal forming. The developed methodology has three major steps: subdivision of B-spline surfaces, detection of protrusions and depressions, and recognition of geometric features for sheet metal forming domain. The input geometry data format of the part is based on an IGES CAD surface model represented in the form of trimmed B-spline surfaces. Each surface is classified or subdivided into different curvature regions with the aid of curvature property surfaces obtained by using symbolic computation of B-spline surfaces. Those regions satisfying a particular geometry and topology relation are recognized as protrusion and depression (DP) shapes. The DP shapes are then classified into different geometric features using a rule-based approach. A verified feasibility study of the developed method is also presented.
Intersecting D3-D3' system at finite temperature
Cottrell, William; Hashimoto, Akikazu; Loveridge, Andrew; Pettengill, Duncan
2015-01-01
We analyze the embedding of probe D3'-brane in the background of $N$ D3-branes at finite temperature, oriented such that they overlap in 1+1 dimensions. As the distance between the D3'-brane and the D3 brane is varied, we find solutions that appear to intersect the horizon. We find that this brane bends logarithmically, making the precise definition of the distance separating the D3 and the D3' brane scale dependent. We also consider the embedding of a probe M5-brane in the background of $N$ M2-branes at finite temperature, for which the logarithmic bending is absent. These systems appear to open a path to probe physics near and behind the black hole horizon in a strictly field theoretic framework.
Constrained optimal steady-state control for isolated traffic intersections
Jack HADDAD; David MAHALEL; Ilya IOSLOVICH; Per-Olof GUTMAN
2014-01-01
The steady-state or cyclic control problem for a simplified isolated traffic intersection is considered. The optimization problem for the green-red switching sequence is formulated with the help of a discrete-event max-plus model. Two steady-state control problems are formulated: optimal steady-state with green duration constraints, and optimal steady-state control with lost time. In the case when the criterion is a strictly increasing, linear function of the queue lengths, the steady-state control problems can be solved analytically. The structure of constrained optimal steady-state traffic control is revealed, and the effect of the lost time on the optimal solution is illustrated.
Ideal theory in semigroups based on intersectional soft sets.
Song, Seok Zun; Kim, Hee Sik; Jun, Young Bae
2014-01-01
The notions of int-soft semigroups and int-soft left (resp., right) ideals are introduced, and several properties are investigated. Using these notions and the notion of inclusive set, characterizations of subsemigroups and left (resp., right) ideals are considered. Using the notion of int-soft products, characterizations of int-soft semigroups and int-soft left (resp., right) ideals are discussed. We prove that the soft intersection of int-soft left (resp., right) ideals (resp., int-soft semigroups) is also int-soft left (resp., right) ideals (resp., int-soft semigroups). The concept of int-soft quasi-ideals is also introduced, and characterization of a regular semigroup is discussed.
Lagrangian intersection Floer theory anomaly and obstruction, part I
Fukaya, Kenji; Ohta, Hiroshi; Ono, Kaoru
2009-01-01
This is a two-volume series research monograph on the general Lagrangian Floer theory and on the accompanying homological algebra of filtered A_\\infty-algebras. This book provides the most important step towards a rigorous foundation of the Fukaya category in general context. In Volume I, general deformation theory of the Floer cohomology is developed in both algebraic and geometric contexts. An essentially self-contained homotopy theory of filtered A_\\infty algebras and A_\\infty bimodules and applications of their obstruction-deformation theory to the Lagrangian Floer theory are presented. Volume II contains detailed studies of two of the main points of the foundation of the theory: transversality and orientation. The study of transversality is based on the virtual fundamental chain techniques (the theory of Kuranishi structures and their multisections) and chain level intersection theories. A detailed analysis comparing the orientations of the moduli spaces and their fiber products is carried out. A self-co...
Lagrangian intersection Floer theory anomaly and obstruction, part II
Fukaya, Kenji; Ohta, Hiroshi; Ono, Kaoru
2009-01-01
This is a two-volume series research monograph on the general Lagrangian Floer theory and on the accompanying homological algebra of filtered A_\\infty-algebras. This book provides the most important step towards a rigorous foundation of the Fukaya category in general context. In Volume I, general deformation theory of the Floer cohomology is developed in both algebraic and geometric contexts. An essentially self-contained homotopy theory of filtered A_\\infty algebras and A_\\infty bimodules and applications of their obstruction-deformation theory to the Lagrangian Floer theory are presented. Volume II contains detailed studies of two of the main points of the foundation of the theory: transversality and orientation. The study of transversality is based on the virtual fundamental chain techniques (the theory of Kuranishi structures and their multisections) and chain level intersection theories. A detailed analysis comparing the orientations of the moduli spaces and their fiber products is carried out. A self-co...
Gender inequalities at the intersection of discriminatory mecha-nisms
Alina Hurubean
2012-04-01
Full Text Available The text aims to present less visible facet of discrimination by identifying social and cultural mechanisms that generate and maintain multiple forms of discrimination, the intersection of which gender has a central position, because he combine with all other criteria of discrimination (race, ethnicity, nationality, religion, social class, age, disability, multiplying the effect of discriminatory behavior. This paper highlights the gender inequalities, the disparities between women and men, boys and girls who are socially constructed which are produced in the process of education and differential gender socialization, asymmetric and hierarchical, correlated with educational and professional orientation and also with labor market access and situation. The fact that gender inequalities exist at a structural level and they are deeply rooted in social practices and collective mental lead to situations where discriminatory behavior manifested without being noticed and as less as sanctioned.
Feature curve extraction from point clouds via developable strip intersection
Kai Wah Lee
2016-04-01
Full Text Available In this paper, we study the problem of computing smooth feature curves from CAD type point clouds models. The proposed method reconstructs feature curves from the intersections of developable strip pairs which approximate the regions along both sides of the features. The generation of developable surfaces is based on a linear approximation of the given point cloud through a variational shape approximation approach. A line segment sequencing algorithm is proposed for collecting feature line segments into different feature sequences as well as sequential groups of data points. A developable surface approximation procedure is employed to refine incident approximation planes of data points into developable strips. Some experimental results are included to demonstrate the performance of the proposed method.
Photodissociation of methyl formate: Conical intersections, roaming and triple fragmentation
Lin, King-Chuen; Tsai, Po-Yu [Department of Chemistry, National Taiwan University, Taipei 106, Taiwan (China); Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan (China); Chao, Meng-Hsuan [Department of Chemistry, National Taiwan University, Taipei 106, Taiwan (China); Kasai, Toshio [Department of Chemistry, National Taiwan University, Taipei 106, Taiwan (China); Graduate School of Science, Department of Chemistry, Osaka University, Toyonaka, 560-0043 Osaka (Japan); Lombardi, Andrea [Dipartimento di Chimica, Università di Perugia, 06123 Perugia (Italy); Palazzetti, Federico [Scuola Normale Superiore, 56126 Pisa (Italy); Aquilanti, Vincenzo [Dipartimento di Chimica, Università di Perugia, 06123 Perugia (Italy); Consiglio Nazionale delle Ricerche, Istituto di Struttura della Materia, 00016 Roma (Italy)
2015-12-31
The photodissociation channels of methyl formate have been extensively investigated by two different advanced experimental techniques, ion imaging and Fourier-Transform-Infrared emission spectroscopy, combined with quantum chemical calculations and molecular dynamics simulations. Our aim is to characterize the role of alternative routes to the conventional transition-state mediated pathway: the roaming and the triple fragmentation processes. The photolysis experiments, carried out at a range of laser wavelengths in the vicinity of the triple fragmentation threshold, beside the simulation of large bunches of classical trajectories with different initial conditions, have shown that both mechanisms share a common path that involves a conical intersection during the relaxation process from the electronic excited state S{sub 1} to the ground state S{sub 0}.
P-brane black holes for general intersections
Ivashchuk, V D
1999-01-01
Black hole generalized p-brane solutions for a wide class of intersectionrules are presented. The solutions are defined on a manifold that contains aproduct of n - 1 Ricci-flat ``internal'' spaces. They are defined up to modulifunctions H_s = H_s(R) obeying a non-linear differential equations (equivalentto Toda-type equations) with certain boundary conditions imposed. Usingconjecture on polynomial structure of H_s for intersections related to Liealgebras, new A_2-dyon solutions are obtained. Two examples of these A_2-dyonsolutions, i.e. dyon in D = 11 supergravity with M2 and M5 branes intersectingat a point and dyon in Kaluza-Klein theory, are considered.
Graphic Intersections: Erga, Parerga and Pro-Erga
Petherbridge, Deanna
2014-03-01
Full Text Available The place where design and art intersect is drawing with its elastic capability of functioning as the whole, the preparatory and the supplementary work. Drawing doesn't only occur at the level of individual practice but can be part of wider "graphic events" where concerted acts of recording, performing, inventing and disseminating link diverse visual practices across time. Two such discursive events are discussed as paradigms: the accidental finding of the Villa Aurea in the 1480s in Rome and Alois Senefelder's lithographic publication of the illustrated Book of Hours of Emperor Maximilian I in 1808. Both were stylistically influential through the popularising of 'grotesque' configurations that unify heterogeneity through linearity.
Segmentation of Overlapping Shapes using Test Ray Intersections
Rasmusson, Allan
be a major task, but in bioimaging and tissue quantification it is often complicated further by the need for segmenting images of overlapping particles, for instance neurons. One approach to segmenting overlapping particles is to oversegment the image into many small regions which are then combined...... into the correct shapes in a postprocessing step. The postprocessing step is unfortunately often both difficult and computationally expensive. Another approach is to incorporate descriptions of the overlapping shapes into a segmentation algorithm which normally only segments the union of all particle profiles....... This may, however, quickly lead to the implementation of complex descriptions of any possible configuration the overlapping shapes may appear in. Presented here is a new approach to segment overlapping shapes which utilizes information gained from probing the image with test rays. Test rays intersections...
The intersection of identity, culture and science engagement
Strong, LaToya
2016-06-01
Ivã Gurgel, Mauricio Pietrocola, and Graciella Watanabe expand upon the existing literature, which links identity and science engagement. Specifically, the authors focus on ways in which the cultural identities of students relate to their engagement in physics. In doing so, Gurgel, Pietrocola, and Watanabe further build upon the idea that one's identity is not immutable, but rather is continually re-constituted throughout life. Employing the lens of ontological authenticity, the authors use three interventions with the purpose of revealing the intersection of students' cultural identity and science. In this paper I extend the dialogue on how we can further explore the link between identity and science engagement, starting first with a consideration of student identity and its significance, before extending this inquiry into the specific field of science.
Intersection of the Sierpinski carpet with its rational translate
Dai Meifeng [Nonlinear Scientific Research Center, Faculty of Science, Jiangsu University, Zhenjiang, Jiangsu 212013 (China)]. E-mail: daimf@ujs.edu.cn; Tian Lixin [Nonlinear Scientific Research Center, Faculty of Science, Jiangsu University, Zhenjiang, Jiangsu 212013 (China)]. E-mail: tianlx@ujs.edu.cn
2007-01-15
Motivated by Mandelbrot's idea of referring to lacunarity of Cantor sets in terms of departure from translation invariance, Nekka and Li studied the properties of these translation sets and showed how they can be used for a classification purpose. In this paper, we pursue this study on the Sierpinski carpet with its rational translate. We also get the fractal structure of intersection I(x, y) of the Sierpinski carpet with its translate. We find that the packing measure of these sets forms a discrete spectrum whose non-zero values come only from shifting numbers with a finite triadic expansion. Concretely, when x and y have a finite triadic expansion, a very brief calculation formula of the measure is given.
Application of Mixed-Methods Approaches to Higher Education and Intersectional Analyses
Griffin, Kimberly A.; Museus, Samuel D.
2011-01-01
In this article, the authors discuss the utility of combining quantitative and qualitative methods in conducting intersectional analyses. First, they discuss some of the paradigmatic underpinnings of qualitative and quantitative research, and how these methods can be used in intersectional analyses. They then consider how paradigmatic pragmatism…
Intersection numbers on the relative Hilbert schemes of points on surfaces
Gholampour, Amin; Sheshmani, Artan
2015-01-01
We study certain top intersection products on the Hilbert scheme of points on a nonsingular surface relative to an effective smooth divisor. We find a formula relating these numbers to the corresponding intersection numbers on the non-relative Hilbert schemes. In particular, we obtain a relative...
Louveton, Nicolas; Bootsma, Reinoud J; Guerin, Perrine; Berthelon, Catherine; Montagne, Gilles
2012-11-01
Safely crossing an intersection requires that drivers actively control their approach to the intersection with respect to characteristics of the flow of incoming traffic. To further our understanding of the perceptual-motor processes involved in this demanding manoeuvre, we designed a driving simulator experiment in which 13 participants actively negotiated intersections by passing through a gap in the train of incoming traffic. Task constraints were manipulated by varying the size of the traffic gap and the initial conditions with respect to the time of arrival of the traffic gap at the intersection. Environment constraints were manipulated by varying the intersection geometry through changes in the angle formed by the crossroads. The results revealed that the task constraints systematically gave rise to continuous and gradual adjustments in approach velocity, initiated well before arriving at the intersection. These functionally appropriate adjustments allowed the drivers to safely cross the intersection, generally just slightly ahead of the center of the traffic gap. Notwithstanding the fact that the geometry of the intersection did not affect the spatiotemporal constraints of the crossing task, approach behavior varied systematically over geometries, suggesting that drivers rely on the traffic gap's bearing angle. Overall, the pattern of results is indicative of a continuous coupling between perception and action, analogous to that observed in locomotor interception tasks.
A "Nation-ized" Intersectional Analysis: The Politics of Transnational Campus Unity
Okazawa-Rey, Margo
2017-01-01
The author introduces the concept of "nation" as an analytic category in contemporary diversity discourse and intersectional analysis of social relations in U.S. higher educational institutions. She then suggests how an intersectional lens that includes nation can expand possibilities for understanding the experiences of international…
Detecting Road Intersections from GPS Traces Using Longest Common Subsequence Algorithm
Xingzhe Xie
2016-12-01
Full Text Available Intersections are important components of road networks, which are critical to both route planning and path optimization. Most existing methods define the intersections as locations where the road users change their moving directions and identify the intersections from GPS traces through analyzing the road users’ turning behaviors. However, these methods suffer from finding an appropriate threshold for the moving direction change, leading to true intersections being undetected or spurious intersections being falsely detected. In this paper, the intersections are defined as locations that connect three or more road segments in different directions. We propose to detect the intersections under this definition by finding the common sub-tracks of the GPS traces. We first detect the Longest Common Subsequences (LCSS between each pair of GPS traces using the dynamic programming approach. Second, we partition the longest nonconsecutive subsequences into consecutive sub-tracks. The starting and ending points of the common sub-tracks are collected as connecting points. At last, intersections are detected from the connecting points through Kernel Density Estimation (KDE. Experimental results show that our proposed method outperforms the turning point-based methods in terms of the F-score.
Armstrong, Denise; Mitchell, Coral
2017-01-01
This qualitative study used a critical intersectional lens to examine how two black female Canadian principals negotiated their professional identities in administrative contexts. Both principals encountered gender and race-related pressures to fit normative expectations of administrators as white males. Navigating their intersecting identities…
Baylina Ferré, Mireia; Rodó de Zárate, Maria
2016-01-01
Intersectionality is a complex concept to deal with when doing research but also when teaching the interrelationships between space and social relations. Here we present "Relief Maps" as a visual tool for teaching intersectionality and its spatial dimension in higher education courses. "Relief Maps" are a model developed for…
Bubar, Roe; Cespedes, Karina; Bundy-Fazioli, Kimberly
2016-01-01
In 2008 EPAS Standards on "Engaging Diversity and Difference in Practice" (2.1.4) added intersectionality (a theory developed by feminist of color) as one aspect to understand diversity, difference, and power in social work curriculum. We consider how intersectionality is omitted in graduate student learning even when class assignments…
Jiménez-Castellanos, Oscar; García, Eugene
2017-01-01
This chapter proposes a conceptual framework that merges intersectionality and policy analysis as an analytical tool to understand the nuanced, multilayered, compounded educational inequality encountered specifically by low-income, Latino Spanish-speaking students in Arizona K-12 public schools as a function of intersecting educational policies.…
Application of Mixed-Methods Approaches to Higher Education and Intersectional Analyses
Griffin, Kimberly A.; Museus, Samuel D.
2011-01-01
In this article, the authors discuss the utility of combining quantitative and qualitative methods in conducting intersectional analyses. First, they discuss some of the paradigmatic underpinnings of qualitative and quantitative research, and how these methods can be used in intersectional analyses. They then consider how paradigmatic pragmatism…
Guanylyl Cyclase C Hormone Axis at the Intersection of Obesity and Colorectal Cancer.
Blomain, Erik S; Merlino, Dante J; Pattison, Amanda M; Snook, Adam E; Waldman, Scott A
2016-09-01
Obesity has emerged as a principal cause of mortality worldwide, reflecting comorbidities including cancer risk, particularly in colorectum. Although this relationship is established epidemiologically, molecular mechanisms linking colorectal cancer and obesity continue to be refined. Guanylyl cyclase C (GUCY2C), a membrane-bound guanylyl cyclase expressed in intestinal epithelial cells, binds the paracrine hormones guanylin and uroguanylin, inducing cGMP signaling in colorectum and small intestine, respectively. Guanylin is the most commonly lost gene product in sporadic colorectal cancer, and its universal loss early in transformation silences GUCY2C, a tumor suppressor, disrupting epithelial homeostasis underlying tumorigenesis. In small intestine, eating induces endocrine secretion of uroguanylin, the afferent limb of a novel gut-brain axis that activates hypothalamic GUCY2C-cGMP signaling mediating satiety opposing obesity. Recent studies revealed that diet-induced obesity suppressed guanylin and uroguanylin expression in mice and humans. Hormone loss reflects reversible calorie-induced endoplasmic reticulum stress and the associated unfolded protein response, rather than the endocrine, adipokine, or inflammatory milieu of obesity. Loss of intestinal uroguanylin secretion silences the hypothalamic GUCY2C endocrine axis, creating a feed-forward loop contributing to hyperphagia in obesity. Importantly, calorie-induced guanylin loss silences the GUCY2C-cGMP paracrine axis underlying obesity-induced epithelial dysfunction and colorectal tumorigenesis. Indeed, genetically enforced guanylin replacement eliminated diet-induced intestinal tumorigenesis in mice. Taken together, these observations suggest that GUCY2C hormone axes are at the intersection of obesity and colorectal cancer. Moreover, they suggest that hormone replacement that restores GUCY2C signaling may be a novel therapeutic paradigm to prevent both hyperphagia and intestinal tumorigenesis in obesity.
Refined open intersection numbers and the Kontsevich-Penner matrix model
Alexandrov, Alexander; Buryak, Alexandr; Tessler, Ran J.
2017-03-01
A study of the intersection theory on the moduli space of Riemann surfaces with boundary was recently initiated in a work of R. Pandharipande, J.P. Solomon and the third author, where they introduced open intersection numbers in genus 0. Their construction was later generalized to all genera by J.P. Solomon and the third author. In this paper we consider a refinement of the open intersection numbers by distinguishing contributions from surfaces with different numbers of boundary components, and we calculate all these numbers. We then construct a matrix model for the generating series of the refined open intersection numbers and conjecture that it is equivalent to the Kontsevich-Penner matrix model. An evidence for the conjecture is presented. Another refinement of the open intersection numbers, which describes the distribution of the boundary marked points on the boundary components, is also discussed.
Nenov, Artur; Vivie-Riedle, Regina de [Department of Chemistry, Ludwig-Maximilians-Univerisitaet, Munich (Germany)
2011-07-21
The knowledge of the intersection space topography of electronic states is essential for deciphering and predicting photoinduced reactions. Michl and Bonacic-Koutecky developed a two-electron two-orbital model that allowed first systematic studies of the chemical origin of conical intersections in strongly polar systems. We generalize this approach to arbitrary functionalized and unfunctionalized polyene systems. For the extended model, a set of mathematical conditions for the formation of conical intersections are derived. These conditions are translated into geometrical motions and electronic effects, which help to explain and predict the structure and energetics of conical intersections. A three-step strategy for the conceptual search of conical intersections is outlined. Its universal validity is demonstrated using the textbook example cyclohexadiene and its functionalized derivative trifluoromethyl-indolylfulgide, a chromophore studied for possible application as a molecular switch.
Nenov, Artur; de Vivie-Riedle, Regina
2011-07-01
The knowledge of the intersection space topography of electronic states is essential for deciphering and predicting photoinduced reactions. Michl and Bonac̆ić-Koutecký developed a two-electron two-orbital model that allowed first systematic studies of the chemical origin of conical intersections in strongly polar systems. We generalize this approach to arbitrary functionalized and unfunctionalized polyene systems. For the extended model, a set of mathematical conditions for the formation of conical intersections are derived. These conditions are translated into geometrical motions and electronic effects, which help to explain and predict the structure and energetics of conical intersections. A three-step strategy for the conceptual search of conical intersections is outlined. Its universal validity is demonstrated using the textbook example cyclohexadiene and its functionalized derivative trifluoromethyl-indolylfulgide, a chromophore studied for possible application as a molecular switch.
Effects of vehicle-pedestrian interaction and speed limit on traffic performance of intersections
Li, Xiang; Sun, Jian-Qiao
2016-10-01
The intersection model consisting of vehicle model, pedestrian model, pedestrian-vehicle interaction model and intersection rules has been presented in this paper. The well-established vehicle and pedestrian movement models in the literature are combined and applied to the intersection system with additional rules. Extensive numerical simulations with different scenarios are carried out. The effects of road speed limit, vehicle arrival rate, pedestrian regularity rate and vehicle rational rate on the intersection performance are quantitatively investigated. Three measures of the traffic performance are studied including transportation efficiency, energy economy and traffic safety. We have found that the energy economy can be achieved with the high transportation efficiency, and that the traffic safety is in conflict with the efficiency. Furthermore, we have found that the pedestrian interference makes the intersection performance worse, resulting in lower transportation efficiency, more energy consumptions and higher safety risk.
The Kinematic Density for Pairs of Intersecting Lines%相交直线偶的运动密度
谢鹏; 谢可瑶; 程孟良
2008-01-01
In this paper,we get a kinematic density formula for pairs of intersecting fines which has not yet been gotten in integral geometry by using the moving orthogonal frames method.And we obtain a kinematic formula of the intersection of the pairs of intersecting lines belonging to convex body K by using it.
Substituent effects on dynamics at conical intersections: Allene and methyl allenes
Neville, Simon P. [Department of Chemistry, University of Ottawa, 10 Marie Curie, Ottawa, Ontario K1N 6N5 (Canada); Wang, Yanmei [State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071 (China); Boguslavskiy, Andrey E.; Stolow, Albert, E-mail: albert.stolow@nrc-cnrc.gc.ca [Department of Chemistry, University of Ottawa, 10 Marie Curie, Ottawa, Ontario K1N 6N5 (Canada); National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6 (Canada); Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa ON K1N 6N5 (Canada); Schuurman, Michael S., E-mail: michael.schuurman@nrc-cnrc.gc.ca [Department of Chemistry, University of Ottawa, 10 Marie Curie, Ottawa, Ontario K1N 6N5 (Canada); National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6 (Canada)
2016-01-07
We report a joint experimental and theoretical study on the ultrafast excited state dynamics of allene and a series of its methylated analogues (1,2-butadiene, 1,1-dimethylallene, and tetramethylallene) in order to elucidate the conical intersection mediated dynamics that give rise to ultrafast relaxation to the ground electronic state. We use femtosecond time-resolved photoelectron spectroscopy (TRPES) to probe the coupled electronic-vibrational dynamics following UV excitation at 200 nm (6.2 eV). Ab initio multiple spawning (AIMS) simulations are employed to determine the mechanistic details of two competing dynamical pathways to the ground electronic state. In all molecules, these pathways are found to involve as follows: (i) twisting about the central allenic C–C–C axis followed by pyramidalization at one of the terminal carbon atoms and (ii) bending of allene moiety. Importantly, the AIMS trajectory data were used for ab initio simulations of the TRPES, permitting direct comparison with experiment. For each molecule, the decay of the TRPES signal is characterized by short (30 fs, 52 fs, 23 fs) and long (1.8 ps, 3.5 ps, [306 fs, 18 ps]) time constants for 1,2-butadiene, 1,1-dimethylallene, and tetramethylallene, respectively. However, AIMS simulations show that these time constants are only loosely related to the evolution of electronic character and actually more closely correlate to large amplitude motions on the electronic excited state, modulating the instantaneous vertical ionization potentials. Furthermore, the fully substituted tetramethylallene is observed to undergo qualitatively different dynamics, as displacements involving the relatively massive methyl groups impede direct access to the conical intersections which give rise to the ultrafast relaxation dynamics observed in the other species. These results show that the branching between the “twisting” and “bending” pathways can be modified via the selective methylation of the terminal
On $k$-connectivity and minimum vertex degree in random $s$-intersection graphs
Zhao, Jun; Gligor, Virgil
2014-01-01
Random s-intersection graphs have recently received much interest [1-9]. In a random s-intersection graph, each vertex is assigned to a set of items in some manner, and two vertices have an edge in between if and only if they share at least s items. In particular, in a uniform random s-intersection graph, each vertex independently selects the same number of items uniformly at random from a common item pool, while in a binomial random s-intersection graph, each item in some item pool is independently attached to each vertex with the same probability. These two graph models have numerous applications; e.g., using uniform random s-intersection graph for cryptanalysis [14,15], and to model secure wireless sensor networks [8-10] and online social networks [11,12], and using a binomial random s-intersection graph for clustering analysis [17], classification [18] and the design of integrated circuits [34]. For binomial/uniform random s-intersection graphs, we present results related to k-connectivity and minimum ver...
Linear Determination of a Camera's Intrinsic Parameters Using Two Intersecting Circles
Xu Chen
2014-03-01
Full Text Available An approach using two intersecting circles is proposed as a linear approach for determining a camera's intrinsic parameters. The two intersecting coplanar circles have four intersection points in the projective plane: two real points and two circular points. In the image plane, the diagonal triangle - on which the image of the four intersection points composes a complete quadrangle - is a self-polar triangle for the projection curves of the circles. The vertex of the self-polar triangle is the null space of the degenerate conic formed by the image of the four intersection points. By solving the three vertices of the self-polar triangle using the image coordinates of the two real intersection points, the degenerate conic can be obtained. The image of the two circular points is then computed from the intersection points of the degenerate conic. Using the image of the circular points from the three images of the same planar pattern with different directions, the intrinsic parameters can be linearly determined.
Linear Determination of a Camera's Intrinsic Parameters Using Two Intersecting Circles
Xu Chen
2014-03-01
Full Text Available An approach using two intersecting circles is proposed as a linear approach for determining a camera's intrinsic parameters. The two intersecting coplanar circles have four intersection points in the projective plane: two real points and two circular points. In the image plane, the diagonal triangle - on which the image of the four intersection points composes a complete quadrangle - is a self-polar triangle for the projection curves of the circles. The vertex of the self-polar triangle is the null space of the degenerate conic formed by the image of the four intersection points. By solving the three vertices of the self-polar triangle using the image coordinates of the two real intersection points, the degenerate conic can be obtained. The image of the two circular points is then computed from the intersection points of the degenerate conic. Using the image of the circular points from the three images of the same planar pattern with different directions, the intrinsic parameters can be linearly determined.
Bauer, Greta R
2014-06-01
Intersectionality theory, developed to address the non-additivity of effects of sex/gender and race/ethnicity but extendable to other domains, allows for the potential to study health and disease at different intersections of identity, social position, processes of oppression or privilege, and policies or institutional practices. Intersectionality has the potential to enrich population health research through improved validity and greater attention to both heterogeneity of effects and causal processes producing health inequalities. Moreover, intersectional population health research may serve to both test and generate new theories. Nevertheless, its implementation within health research to date has been primarily through qualitative research. In this paper, challenges to incorporation of intersectionality into population health research are identified or expanded upon. These include: 1) confusion of quantitative terms used metaphorically in theoretical work with similar-sounding statistical methods; 2) the question of whether all intersectional positions are of equal value, or even of sufficient value for study; 3) distinguishing between intersecting identities, social positions, processes, and policies or other structural factors; 4) reflecting embodiment in how processes of oppression and privilege are measured and analysed; 5) understanding and utilizing appropriate scale for interactions in regression models; 6) structuring interaction or risk modification to best convey effects, and; 7) avoiding assumptions of equidistance or single level in the design of analyses. Addressing these challenges throughout the processes of conceptualizing and planning research and in conducting analyses has the potential to improve researchers' ability to more specifically document inequalities at varying intersectional positions, and to study the potential individual- and group-level causes that may drive these observed inequalities. A greater and more thoughtful incorporation
The intersection of online social networking with medical professionalism.
Thompson, Lindsay A; Dawson, Kara; Ferdig, Richard; Black, Erik W; Boyer, J; Coutts, Jade; Black, Nicole Paradise
2008-07-01
To measure the frequency and content of online social networking among medical students and residents. Using the online network Facebook, we evaluated online profiles of all medical students (n = 501) and residents (n = 312) at the University of Florida, Gainesville. Objective measures included the existence of a profile, whether it was made private, and any personally identifiable information. Subjective outcomes included photographic content, affiliated social groups, and personal information not generally disclosed in a doctor-patient encounter. Social networking with Facebook is common among medical trainees, with 44.5% having an account. Medical students used it frequently (64.3%) and residents less frequently (12.8%, p personally identifiable information, only a third (37.5%) were made private, and some accounts displayed potentially unprofessional material. There was a significant decline in utilization of Facebook as trainees approached medical or residency graduation (first year as referent, years 3 and 4, p profile. With a significant proportion having subjectively inappropriate content, ACGME competencies in professionalism must include instruction on the intersection of personal and professional identities.
Fluid flow and dissipation in intersecting counter-flow pipes
Pekkan, Kerem
2005-11-01
Intersecting pipe junctions are common in industrial and biomedical flows. For the later application, standard surgical connections of vessel lumens results a ``+'' shaped topology through a side-to-side or end-to-side anastomosis. Our earlier experimental/computational studies have compared different geometries quantifying the hydrodynamic power loss through the junction where dominant coherent structures are identified. In this study we have calculated the contribution of these structures to the total energy dissipation and its spatial distribution in the connection. A large set of idealized models are studied in which the basic geometric configuration is parametrically varied (from side-to-side to end-to-side anastomosis) which quantified the strength of the secondary flows and coherent structures as a function of the geometric configuration. Steady-state, 3D, incompressible computations are performed using the commercial CFD code FIDAP with unstructured tetrahedral grids. Selected cases are compared with the in-house code results (in Cartesian and structured grids). Grid verification and experimental validation with flow-vis and PIV are presented. Identifying the dissipation hot-spots will enable a targeted inverse design of the junction by reducing the degree of optimization with a focused parameter space.
Minimal left-right symmetric intersecting D-brane model
Anchordoqui, Luis A; Goldberg, Haim; Huang, Xing; Lust, Dieter; Taylor, Tomasz R
2016-01-01
We investigate left-right symmetric extensions of the standard model based on open strings ending on D-branes, with gauge bosons due to strings attached to stacks of D-branes and chiral matter due to strings stretching between intersecting D-branes. The left-handed and right-handed fermions transform as doublets under Sp(1)_L and Sp(1)_R, and so their masses must be generated by the introduction of Higgs fields in a bi-fundamental (2,2) representation under the two Sp(1) gauge groups. For such D-brane configurations the left-right symmetry must be broken by Higgs fields in the doublet representation of Sp(1)_R and therefore Majorana mass terms are suppressed by some higher physics scale. The left-handed and right-handed neutrinos pair up to form Dirac fermions which maneuver the decay widths of the right-handed W' boson to yield comparable branching fractions into dilepton and dijets channels. Using the most recent searches at LHC13 Run II with 2016 data we constrain the (g_R, m_{W'}) parameter space. Our ana...
Belonging among newcomer youths: intersecting experiences of inclusion and exclusion.
Caxaj, C Susana; Berman, Helene
2010-01-01
Belonging has been identified as an important resource for health and well-being in the lives of youths. Thus, it is an important concept for upstream health promotion and culturally safe and relevant nursing care. While many researchers acknowledge the importance of the social, cultural, and political context in the lives of newcomer youths, little research has examined the sociopolitical processes inherent in immigrant and refugee youths' experiences of belonging. By employing an intersectional and postcolonial perspective, this study explored newcomer youths' gendered, racialized, and class experiences of inclusion and exclusion that ultimately influenced their sense of belonging in their country of resettlement. Through an examination of online blogs in the United States, the United Kingdom, Australia, and secondary analyses of transcribed interviews from a previous study conducted in Canada, experiences of belonging were revealed to be shaped by complex and multifaceted structures of oppression. Through individual and collective efforts of resistance and resiliency, newcomer youths worked to construct a sense of belonging in their daily lives. Despite these participants' demonstrated strengths, it is evident that more work is needed to support newcomer youths' sense of belonging and well-being throughout resettlement. Implications for nursing practice and research are discussed.
Anthropology and cultural neuroscience: creating productive intersections in parallel fields.
Brown, R A; Seligman, R
2009-01-01
Partly due to the failure of anthropology to productively engage the fields of psychology and neuroscience, investigations in cultural neuroscience have occurred largely without the active involvement of anthropologists or anthropological theory. Dramatic advances in the tools and findings of social neuroscience have emerged in parallel with significant advances in anthropology that connect social and political-economic processes with fine-grained descriptions of individual experience and behavior. We describe four domains of inquiry that follow from these recent developments, and provide suggestions for intersections between anthropological tools - such as social theory, ethnography, and quantitative modeling of cultural models - and cultural neuroscience. These domains are: the sociocultural construction of emotion, status and dominance, the embodiment of social information, and the dual social and biological nature of ritual. Anthropology can help locate unique or interesting populations and phenomena for cultural neuroscience research. Anthropological tools can also help "drill down" to investigate key socialization processes accountable for cross-group differences. Furthermore, anthropological research points at meaningful underlying complexity in assumed relationships between social forces and biological outcomes. Finally, ethnographic knowledge of cultural content can aid with the development of ecologically relevant stimuli for use in experimental protocols.
Cognitive engineering and health informatics: Applications and intersections.
Hettinger, A Zachary; Roth, Emilie M; Bisantz, Ann M
2017-03-01
Cognitive engineering is an applied field with roots in both cognitive science and engineering that has been used to support design of information displays, decision support, human-automation interaction, and training in numerous high risk domains ranging from nuclear power plant control to transportation and defense systems. Cognitive engineering provides a set of structured, analytic methods for data collection and analysis that intersect with and complement methods of Cognitive Informatics. These methods support discovery of aspects of the work that make performance challenging, as well as the knowledge, skills, and strategies that experts use to meet those challenges. Importantly, cognitive engineering methods provide novel representations that highlight the inherent complexities of the work domain and traceable links between the results of cognitive analyses and actionable design requirements. This article provides an overview of relevant cognitive engineering methods, and illustrates how they have been applied to the design of health information technology (HIT) systems. Additionally, although cognitive engineering methods have been applied in the design of user-centered informatics systems, methods drawn from informatics are not typically incorporated into a cognitive engineering analysis. This article presents a discussion regarding ways in which data-rich methods can inform cognitive engineering.
Divine Intersections: Hindu Ritual and the Incorporation of Religious Others
Kathinka Frøystad
2012-08-01
Full Text Available This article throws the study of multireligious sociality in Western contexts into sharp relief by examining the case of India. Much of the current scholarship of cosmopolitanism and multiculturalism tends to assume that religious beliefs, practices and spaces make the respective religious communities close entirely in upon themselves. While this assumption may hold true for most of the Western settings we study, it does not necessarily give an accurate description of the conditions for multireligious sociality in other parts of the world. In India, for instance, religious boundaries still display signs of malleability despite the religious politicization and occasional interreligious violence of the past decades. Drawing on recent anthropological research, this article shows that people of different religious denominations still visit Sufi shrines, that Hindus still incorporate ritual elements and divine beings from the religious traditions of their Others and that they exercise a wide personal choice in terms of spiritual activities, thus enabling spiritual paths that cross in and out of Hinduism. In a Hindu context rituals do not necessarily have an insulating effect; they may also provide points of intersection that open up toward the Other, thus fostering familiarity and recognition. Similar arguments have been made for Buddhist settings. The question is thus whether the current scholarship of cosmopolitanism may entail a certain monotheistic bias that needs to accounted for, something that is of particular importance when theorizing in ways that make universal claims.
A secure multi-party computation solution to intersection problems of sets and rectangles
LI Shundong; DAI Yiqi; WANG Daoshun; LUO Ping
2006-01-01
Secure multi-party computation (SMC) is a research focus in international cryptographic community. At present, there is no SMC solution to the intersection problem of sets. In this paper, we first propose a SMC solution to this problem. Applying Cantor encoding method to computational geometry problems, and based on the solution to set-intersection problem, we further propose solutions to points inclusion problem and intersection problem of rectangles and further prove their privacy-preserving property with widely accepted simulation paradigm. Compared with the known solutions, these new solutions are of less computational complexity and less communication complexity, and have obvious superiority in computational and communication complexity.
UpSetR: an R package for the visualization of intersecting sets and their properties.
Conway, Jake R; Lex, Alexander; Gehlenborg, Nils
2017-09-15
Venn and Euler diagrams are a popular yet inadequate solution for quantitative visualization of set intersections. A scalable alternative to Venn and Euler diagrams for visualizing intersecting sets and their properties is needed. We developed UpSetR, an open source R package that employs a scalable matrix-based visualization to show intersections of sets, their size, and other properties. UpSetR is available at https://github.com/hms-dbmi/UpSetR/ and released under the MIT License. A Shiny app is available at https://gehlenborglab.shinyapps.io/upsetr/ . nils@hms.harvard.edu. Supplementary data are available at Bioinformatics online.
An Examination of the Sequence of Intersecting Seal and Laser Printing Toner Line.
Li, Biao; Ouyang, Guoliang
2017-03-01
Examining the sequence of intersecting seal and laser printing line is a significant method of determining the authenticity and validity of documents. In this study, five brands of stamp pad inks, three types of inkpads and seven kinds of laser printers were used to make heterogeneous line intersections. Observation method of physical characteristics, scraping technique and fluorescence method was used to determine the sequence of intersecting lines. Distinguishing features were noted between the materials produced in both sequences. As the results obtained from the study were positive, these features might provide a scientific basis for accurately determining the sequence between laser printing line and inkpad (stamp pad ink) seal.
Riedle, Eberhard; Roos, Matthias K.; Thallmair, Sebastian; Sailer, Christian F.; Krebs, Nils; Fingerhut, Benjamin P.; de Vivie-Riedle, Regina
2017-09-01
Light induced bond cleavage is an ubiquitous process in large molecules, yet its quantum nature is not fully understood. We present a comprehensive description of the ultrafast light induced Csbnd Cl bond cleavage in diarylmethyl chlorides combining femtosecond transient absorption measurements with ab initio calculations. We observe a delayed appearance of radicals (80 fs) and cations (125 fs). The excited state wavepacket moves initially toward two conical intersections and the passing through these intersections determines the partitioning into the differing product channels. Different locations of the conical intersections explain the observed delay times.
Photonic Crystal Waveguide Intersection Based on Self-Imaging of Multi-Mode Interference
DING Wei-Qiang; TANG Dong-Hua; CHEN Li-Xue; ZHAO Yuan; Liu Yan
2007-01-01
@@ A new mechanism of intersection formed by two line defect photonic crystal (PC) waveguides are numerically investigated using the finite-difference time-domain method. The results show that the normalized crosstalk is smaller than 10-4; the reflection is smaller than 10-3, and the transmission is larger than 0.999. The authors analyse the physical origins and find that a modified self-imaging process in the intersected multi-mode region is the main reason of the excellent performance. This kind of multi-mode interference based intersection may find potential applications in PC optical circuits.
Media Representation of Women Politicians from a Gender to an Intersectionality Perspective
Fiig, Christina
2010-01-01
the debate on the media as a powerful political site for different groups of men and women politicians. The analytical point of the article is that a perspective of intersectionality deepens the understanding of the ways that the media organize power through stereotypical representation and homogenization......This article investigates media representation from a perspective of intersectionality defined as one that deconstructs the category ‘woman’ by looking at different social divisions such as class, ethnicity, gender, race and sexuality. An intersectionality perspective is constructive in broadening...
Optimal traffic light control method for a single intersection based on hybrid systems
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.
A Game of Simon Says: Latin America’s Left Turn and Its Effects on US Security
2008-05-01
containment of communism, particularly in the Western Hemisphere, since the end of World War II. However, a closer look at the region south of the Rio ...country’s direc- tion. Some autocratic states may hold elections for show (e.g., Saddam Hussein’s Iraq), but the results—much like a rigged carnival game...the Rio Grande. Secretary of State Condoleezza Rice called Venezue- la’s Chavez a “destabilizing force” within the Latin American region.72 Former
Wang, Ting-Fang; Chen, Li-Tzu; Wang, Andrew H-J
2008-01-01
The RecA family proteins mediate homologous recombination, a ubiquitous mechanism for repairing DNA double-strand breaks (DSBs) and stalled replication forks. Members of this family include bacterial RecA, archaeal RadA and Rad51, and eukaryotic Rad51 and Dmc1. These proteins bind to single-stranded DNA at a DSB site to form a presynaptic nucleoprotein filament, align this presynaptic filament with homologous sequences in another double-stranded DNA segment, promote DNA strand exchange and then dissociate. It was generally accepted that RecA family proteins function throughout their catalytic cycles as right-handed helical filaments with six protomers per helical turn. However, we recently reported that archaeal RadA proteins can also form an extended right-handed filament with three monomers per helical turn and a left-handed protein filament with four monomers per helical turn. Subsequent structural and functional analyses suggest that RecA family protein filaments, similar to the F1-ATPase rotary motor, perform ATP-dependent clockwise axial rotation during their catalytic cycles. This new hypothesis has opened a new avenue for understanding the molecular mechanism of RecA family proteins in homologous recombination.
Clayton, Michael; Myers, Emily
2008-01-01
The present study attempted to further existing literature on increasing safe driving practices through visual prompts by targeting turn signal use at a 4-way intersection. Drivers exiting a university parking garage were presented with a visual prompt ("Please Signal and Drive Safely") and then observed for turn signal use while entering an…
On intersection of two embedded spheres in 3-space (Russian version)
Rukhovich, Alexey
2011-01-01
We study intersection of two polyhedral spheres without self-intersections in 3-space. We find necessary and sufficient conditions on sequences x = x_1,x_2,...,x_n, y = y_1,y_2,...,y_n of positive integers, for existence of 2-dimensional polyhedra f,g in R^3 homeomorphic to the sphere and such that * f-g has n connected components, of which the i-th one has x_i neighbors in f and * g-f has n connected components, of which the i-th one has y_i neighbors in g. Analogously we study intersection of three polyhedral spheres without self-intersections in 3-space. Russian version is accessible to high-school teachers and students interested in mathematics.
LI Zhanli; SUN Xiuying
2006-01-01
VRML(Virtual Reality Modeling Language) format as an international standard for virtual reality, has already been widely adopted for graphical representation of 3D objects over the Web. Adopting VRML model in RP(Rapid Prototyping) can reduce the precision loss which is caused by triangulation in generating STL file. Hence exploring a slicing method and developing a slicing software for VRML model is important and significant to improve the accuracy of RP products. Finding intersections of a plane and VRML model is the key operation in slicing algorithm. This paper presents a method for calculating the intersections between a set of parallel planes and VRML geometric primitives. Based on the analysis of the relative position between a plane and a geometric primitive, intersection conditions in all cases were obtained, and the geometric parameters and corresponding equations of intersections were derived. The algorithm had been tested, and applications show that it is robust and effective.
EnviroAtlas Estimated Intersection Density of Walkable Roads Web Service
U.S. Environmental Protection Agency — This EnviroAtlas dataset estimates the intersection density of walkable roads within a 750 meter radius of any given 10 meter pixel in each EnviroAtlas community....
Intersecting Non-extreme p-Branes and Linear Dilaton Background
Chen, C M; Ohta, N; Chen, Chiang-Mei; Gal'tsov, Dmitri V.; Ohta, Nobuyoshi
2005-01-01
We construct the general static solution to the supergravity action containing gravity, the dilaton and a set of antisymmetric forms describing the intersecting branes delocalized in the relative transverse dimensions. The solution is obtained by reducing the system to a set of separate Liouville equations (the intersection rules implying the separability); it contains the maximal number of free parameters corresponding to the rank of the differential equations. Imposing the requirement of the absence of naked singularities, we show that the general configurations are restricted to two and only two classes: the usual asymptotically flat intersecting branes, and the intersecting branes some of which are asymptotically flat and some approach the linear dilaton background at infinity. In both cases the configurations are black. These are supposed to be relevant for the description of the thermal phase of the QFT's in the corresponding Domain-Wall/QFT duality.
Open intersection numbers, Kontsevich--Penner model and cut-and-join operators
Alexandrov, Alexander
2014-01-01
We continue our investigation of the Kontsevich--Penner model, which describes intersection theory on moduli spaces both for open and closed curves. In particular, we show how Buryak's residue formula, which connects two generating functions of intersection numbers, appears in the general context of matrix models and tau-functions. This allows us to prove that the Kontsevich--Penner matrix integral indeed describes open intersection numbers. For arbitrary $N$ we show that the string and dilaton equations completely specify the solution of the KP hierarchy. We derive a complete family of the Virasoro and W-constraints and using these constraints we construct the cut-and-join operators. The case $N=1$, corresponding to open intersection numbers, is particularly interesting: for this case we obtain two different families of the Virasoro constraints, so that the difference between them describes the dependence of the tau-function on even times.
Vehicular crash data used to rank intersections by injury crash frequency and severity
Liu, Yi; Li, Zongzhi; Liu, Jingxian; Patel, Harshingar
2016-01-01
.... For each intersection, vehicular crashes were counted by crash severity levels, including fatal, injury Types A, B, and C for major, moderate, and minor injury levels, property damage only (PDO), and unknown...
An Intersectional Analysis of Visual Media: A Case of Diesel Advertisements
Anthony Justin Barnum; Anna M. Zajicek
2008-01-01
This study is intended to advance the application of an intersectional approach that focuses on the simultaneous operation of gender, race/ethnicity, and sexuality to the analysis of visual media, such as advertisements...
Advancing Social Justice Work at the Intersections of Multiple Privileged Identities
Kendall, Frances E.; Wijeyesinghe, Charmaine L.
2017-01-01
The authors discuss how the concept of social location and tenets of intersectionality inform the understanding of power and privilege, our work with people with multiple privileged identities, and the preparation of social justice educators.
Non-adiabatic dynamics close to conical intersections and the surface hopping perspective
João Pedro eMalhado
2014-11-01
Full Text Available Conical intersections play a major role in the current understanding of electronic de-excitation in polyatomic molecules, and thus in the description of photochemistry and photo physics of molecular systems. This article reviews aspects of the basic theory underlying the description of non-adiabatic transitions at conical intersections, with particular emphasis on the important case when the dynamics of the nuclei are treated classically. Within this classical nuclear motion framework, the main aspects of the surface hopping methodology in the conical intersection context are presented. The emerging picture from this treatment is that of electronic transitions around conical intersections dominated by the interplay of the nuclear velocity and the derivative non-adiabatic coupling vector field.
Monocular trajectory intersection method for 3D motion measurement of a point target
无
2009-01-01
This article proposes a monocular trajectory intersection method,a videometrics measurement with a mature theoretical system to solve the 3D motion parameters of a point target.It determines the target’s motion parameters including its 3D trajectory and velocity by intersecting the parametric trajectory of a motion target and series of sight-rays by which a motion camera observes the target,in contrast with the regular intersection method for 3D measurement by which the sight-rays intersect at one point.The method offers an approach to overcome the technical failure of traditional monocular measurements for the 3D motion of a point target and thus extends the application fields of photogrammetry and computer vision.Wide application is expected in passive observations of motion targets on various mobile beds.
The study of envorinmental state on road intersections based on emissions of car engines in Zhytomyr
Titarenko V.
2016-08-01
Full Text Available This paper presents results of the studies of environmental conditions on road intersections based on car engine emissions in Zhitomir. Statistical methods were used to determine the intensity of traffic flows based on transport emissions according to video monitoring records. Intersections with the highest intensity of traffic flows, where there is a high risk of car emissions accumulation above the applicable standard, were chosen for the assessment of ecological sustainability. Calculation of pollution was done for the intersection of Nebesnoi Sotni street and M. Grushevskogo street. The results of calculation were compared with the limit of affordable concentration and conclusions that emphasize difficulty of the problem and the emergence of its solving. The system of ecological safety in Zhitomir requires significant improvements taking into account the exceeding of factual values of pollution over normative values. Recommendations concerning of ecological sustainability of intersections can be developed through the optimization of traffic flows with the use of intellectual traffic systems.
Massachusetts Bay - Internal Wave Packets Digitized from SAR Imagery and Intersected with Bathymetry
National Oceanic and Atmospheric Administration, Department of Commerce — This feature class contains internal wave packets digitized from SAR imagery and intersected with bathymetry for Massachusetts Bay. The internal wave packets were...