Michigan urban trunkline intersections safety performance functions (SPFs) development and support.

DOT National Transportation Integrated Search

2015-06-01

This study involves the development of safety performance functions (SPFs) for signalized and stop-controlled intersections : located along urban and suburban arterials in the state of Michigan. Extensive databases were developed that resulted in the...

Are signalized intersections with cycle tracks safer? A case-control study based on automated surrogate safety analysis using video data.

PubMed

Zangenehpour, Sohail; Strauss, Jillian; Miranda-Moreno, Luis F; Saunier, Nicolas

2016-01-01

Cities in North America have been building bicycle infrastructure, in particular cycle tracks, with the intention of promoting urban cycling and improving cyclist safety. These facilities have been built and expanded but very little research has been done to investigate the safety impacts of cycle tracks, in particular at intersections, where cyclists interact with turning motor-vehicles. Some safety research has looked at injury data and most have reached the conclusion that cycle tracks have positive effects of cyclist safety. The objective of this work is to investigate the safety effects of cycle tracks at signalized intersections using a case-control study. For this purpose, a video-based method is proposed for analyzing the post-encroachment time as a surrogate measure of the severity of the interactions between cyclists and turning vehicles travelling in the same direction. Using the city of Montreal as the case study, a sample of intersections with and without cycle tracks on the right and left sides of the road were carefully selected accounting for intersection geometry and traffic volumes. More than 90h of video were collected from 23 intersections and processed to obtain cyclist and motor-vehicle trajectories and interactions. After cyclist and motor-vehicle interactions were defined, ordered logit models with random effects were developed to evaluate the safety effects of cycle tracks at intersections. Based on the extracted data from the recorded videos, it was found that intersection approaches with cycle tracks on the right are safer than intersection approaches with no cycle track. However, intersections with cycle tracks on the left compared to no cycle tracks seem to be significantly safer. Results also identify that the likelihood of a cyclist being involved in a dangerous interaction increases with increasing turning vehicle flow and decreases as the size of the cyclist group arriving at the intersection increases. The results highlight the important role of cycle tracks and the factors that increase or decrease cyclist safety. Results need however to be confirmed using longer periods of video data. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evaluation of life cycle impacts of intersection control type selection [final report].

DOT National Transportation Integrated Search

2016-05-05

The methodology provided in this report provides guidance for NCDOT conversions of twoway : stop controlled intersections to other intersection types to enhance the effective allocation of : public funds. The findings of this project have been inc...

Sustainable intersection control to accommodate urban freight mobility.

DOT National Transportation Integrated Search

2009-08-01

In this research, we studied green extension of a two-phased vehicleactuated signal at an isolated : intersection between two one-way streets. The green phase is extended by a preset time interval, referred to : as critical gap, from the time of a...

Driver behavior analysis for right-turn drivers at signalized intersections using SHRP 2 naturalistic driving study data.

PubMed

Wu, Jianqing; Xu, Hao

2017-12-01

Understanding driver behavior is important for traffic safety and operation, especially at intersections where different traffic movements conflict. While most driver-behavior studies are based on simulation, this paper documents the analysis of driver-behavior at signalized intersections with the SHRP 2 Naturalistic Driving Study (NDS) data. This study analyzes the different influencing factors on the operation (speed control) and observation of right-turn drivers. A total of 300 NDS trips at six signalized intersections were used, including the NDS time-series sensor data, the forward videos and driver face videos. Different factors of drivers, vehicles, roads and environments were studied for their influence on driver behavior. An influencing index function was developed and the index was calculated for each influencing factor to quantitatively describe its influencing level. The influencing index was applied to prioritize the factors, which facilitates development and selection of safety countermeasures to improve intersection safety. Drivers' speed control was analyzed under different conditions with consideration of the prioritized influencing factors. Vehicle type, traffic signal status, conflicting traffic, conflicting pedestrian and driver age group were identified as the five major influencing factors on driver observation. This research revealed that drivers have high acceleration and low observation frequency under Right-Turn-On-Red (RTOR), which constituted potential danger for other roadway users, especially for pedestrians. As speed has a direct influence on crash rates and severities, the revealed speed patterns of the different situations also benefit selection of safety countermeasures at signalized intersections. Published by Elsevier Ltd.

Low-cost safety enhancements for stop-controlled and signalized intersections

DOT National Transportation Integrated Search

2009-05-01

The purpose of this document is to present information on suggested effective, low-cost intersection countermeasures developed using intersection safety research results and input from an intersection safety expert panel. These low-cost countermeasur...

Safety Evaluation of Destination Lighting at Stop-Controlled Cross Intersections

DOT National Transportation Integrated Search

2018-02-02

Unlit or inadequately lit intersections reduce the ability of drivers to recognize upcoming intersections during nighttime hours. Drivers also face difficulty in properly negotiating the intersection because lack of adequate lighting increases the li...

Evaluation of a Risk Awareness Perception Training Program on Novice Teen Driver Behavior at Left-Turn Intersections.

PubMed

McDonald, Catherine C; Kandadai, Venk; Loeb, Helen; Seacrist, Thomas; Lee, Yi-Ching; Bonfiglio, Dana; Fisher, Donald L; Winston, Flaura K

Collisions at left turn intersections are among the most prevalent types of teen driver serious crashes, with inadequate surveillance as a key factor. Risk awareness perception training (RAPT) has shown effectiveness in improving hazard anticipation for latent hazards. The goal of this study was to determine if RAPT version 3 (RAPT-3) improved intersection turning behaviors among novice teen drivers when the hazards were not latent and frequent glancing to multiple locations at the intersection was needed. Teens aged 16-18 with ≤180 days of licensure were randomly assigned to: 1) an intervention group (n=18) that received RAPT-3 (Trained); or 2) a control group (n=19) that received no training (Untrained). Both groups completed RAPT-3 Baseline Assessment and the Trained group completed RAPT-3 Training and RAPT-3 Post Assessment. Training effects were evaluated on a driving simulator. Simulator ( gap selection errors and collisions ) and eye tracker ( traffic check errors) metrics from six left-turn stop sign controlled intersections in the Simulated Driving Assessment (SDA) were analyzed. The Trained group scored significantly higher in RAPT-3 Post Assessment than RAPT-3 Baseline Assessment (p< 0.0001). There were no significant differences in either traffic check and gap selection errors or collisions among Trained and Untrained teens in the SDA. Though Trained teens learned about hazard anticipation related to latent hazards, learning did not translate to performance differences in left-turn stop sign controlled intersections where the hazards were not latent. Our findings point to further research to better understand the challenges teens have with left turn intersections.

Evaluating the Operational Features of an Unconventional Dual-Bay U-Turn Design for Intersections

PubMed Central

Xiang, Yun; Li, Zhibin; Wang, Wei; Chen, Jingxu; Wang, Hao; Li, Ye

2016-01-01

Median U-turn intersection treatment (MUTIT) has been considered an alternative measure to reduce congestion and traffic conflict at intersection areas. The MUTIT is sometimes difficult to implement in the field because it requires wide median on arterials for U-turn vehicles. The objective of this study is to introduce an unconventional U-turn treatment (UUT) for intersections which requires less median space but is also effective. The UUT has a dual-bay design with different turning radiuses for small and large vehicles. The VISSIM simulation model was developed to evaluate the operational features of the UUT. The model was calibrated using data collected from intersections in China. The capacity, delay and number of stops were evaluated and compared with the direct-left-turn (DLT) for the same intersections. The results showed that the UUT significantly improved the operations at intersection areas, especially when volume/capacity ratio is small, and ratio of left-turn to through traffic is small. With the UUT, the capacity is increased by 9.81% to 10.38%, vehicle delay is decreased by 18.5% to 40.1%, and number of stops is decreased by 23.19% to 36.62%, when volume/capacity ratio is less than 0.50. The study also found that traffic efficiency could be further improved when the UUT is designed in conjunction with signal control. In the case, the UUT plus signalized control increases the capacity by 25% to 26.02%, decreases vehicle delay by 50.5% to 55.8%, and reduces number of stops by 69.5%, compared with the traditional DLT. PMID:27467127

Evaluating the Operational Features of an Unconventional Dual-Bay U-Turn Design for Intersections.

PubMed

Xiang, Yun; Li, Zhibin; Wang, Wei; Chen, Jingxu; Wang, Hao; Li, Ye

2016-01-01

Median U-turn intersection treatment (MUTIT) has been considered an alternative measure to reduce congestion and traffic conflict at intersection areas. The MUTIT is sometimes difficult to implement in the field because it requires wide median on arterials for U-turn vehicles. The objective of this study is to introduce an unconventional U-turn treatment (UUT) for intersections which requires less median space but is also effective. The UUT has a dual-bay design with different turning radiuses for small and large vehicles. The VISSIM simulation model was developed to evaluate the operational features of the UUT. The model was calibrated using data collected from intersections in China. The capacity, delay and number of stops were evaluated and compared with the direct-left-turn (DLT) for the same intersections. The results showed that the UUT significantly improved the operations at intersection areas, especially when volume/capacity ratio is small, and ratio of left-turn to through traffic is small. With the UUT, the capacity is increased by 9.81% to 10.38%, vehicle delay is decreased by 18.5% to 40.1%, and number of stops is decreased by 23.19% to 36.62%, when volume/capacity ratio is less than 0.50. The study also found that traffic efficiency could be further improved when the UUT is designed in conjunction with signal control. In the case, the UUT plus signalized control increases the capacity by 25% to 26.02%, decreases vehicle delay by 50.5% to 55.8%, and reduces number of stops by 69.5%, compared with the traditional DLT.

The impact of iterated games on traffic flow at noncontrolled intersections

NASA Astrophysics Data System (ADS)

Zhao, Chao; Jia, Ning

2015-05-01

Intersections without signal control widely exist in urban road networks. This paper studied the traffic flow in a noncontrolled intersection within an iterated game framework. We assume drivers have learning ability and can repetitively adjust their strategies (to give way or to rush through) in the intersection according to memories. A cellular automata model is applied to investigate the characteristics of the traffic flow. Numerical experiments indicate two main findings. First, the traffic flow experiences a "volcano-shaped" fundamental diagram with three different phases. Second, most drivers choose to give way in the intersection, but the aggressive drivers cannot be completely eliminated, which is coincident with field observations. Analysis are also given out to explain the observed phenomena. These findings allow deeper insight of the real-world bottleneck traffic flow.

Emergency vehicle traffic signal preemption system

NASA Technical Reports Server (NTRS)

Foster, Conrad F. (Inventor); Bachelder, Aaron D. (Inventor)

2005-01-01

An emergency vehicle traffic light preemption system for preemption of traffic lights at an intersection to allow safe passage of emergency vehicles. The system includes a real-time status monitor of an intersection which is relayed to a communications controller for transmission to emergency vehicles as well as to a central dispatch office. The system also provides for audio warnings at an intersection to protect pedestrians who may not be in a position to see visual warnings or for various reasons cannot hear the approach of emergency vehicles. A transponder mounted on an emergency vehicle provides autonomous control so the vehicle operator can attend to getting to an emergency and not be concerned with the operation of the system. Activation of a Code 3 situation provides communications with each intersection being approached by an emergency vehicle and indicates whether the intersection is preempted or if there is any conflict with other approaching emergency vehicles. On-board diagnostics handle various information including heading, speed, and acceleration sent to a communications controller which is transmitted to an intersection and which also simultaneously receives information regarding the status of an intersection.

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

PubMed

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.

Street deployment of pedestrian control smart traffic signals.

DOT National Transportation Integrated Search

2009-04-01

Smart Signals is a term used to describe the application of network based distributed control technology to the control of traffic signals at signalized intersections. Presently, signalized intersections use a centralized control approach where all o...

Roadside-based communication system and method

NASA Technical Reports Server (NTRS)

Bachelder, Aaron D. (Inventor)

2007-01-01

A roadside-based communication system providing backup communication between emergency mobile units and emergency command centers. In the event of failure of a primary communication, the mobile units transmit wireless messages to nearby roadside controllers that may take the form of intersection controllers. The intersection controllers receive the wireless messages, convert the messages into standard digital streams, and transmit the digital streams along a citywide network to a destination intersection or command center.

An immersive virtual peer for studying social influences on child cyclists' road-crossing behavior.

PubMed

Babu, Sabarish V; Grechkin, Timofey Y; Chihak, Benjamin; Ziemer, Christine; Kearney, Joseph K; Cremer, James F; Plumert, Jodie M

2011-01-01

The goal of our work is to develop a programmatically controlled peer to bicycle with a human subject for the purpose of studying how social interactions influence road-crossing behavior. The peer is controlled through a combination of reactive controllers that determine the gross motion of the virtual bicycle, action-based controllers that animate the virtual bicyclist and generate verbal behaviors, and a keyboard interface that allows an experimenter to initiate the virtual bicyclist's actions during the course of an experiment. The virtual bicyclist's repertoire of behaviors includes road following, riding alongside the human rider, stopping at intersections, and crossing intersections through specified gaps in traffic. The virtual cyclist engages the human subject through gaze, gesture, and verbal interactions. We describe the structure of the behavior code and report the results of a study examining how 10- and 12-year-old children interact with a peer cyclist that makes either risky or safe choices in selecting gaps in traffic. Results of our study revealed that children who rode with a risky peer were more likely to cross intermediate-sized gaps than children who rode with a safe peer. In addition, children were significantly less likely to stop at the last six intersections after the experience of riding with the risky than the safe peer during the first six intersections. The results of the study and children's reactions to the virtual peer indicate that our virtual peer framework is a promising platform for future behavioral studies of peer influences on children's bicycle riding behavior. © 2011 IEEE Published by the IEEE Computer Society

Examination of the reliability of the crash modification factors using empirical Bayes method with resampling technique.

PubMed

Wang, Jung-Han; Abdel-Aty, Mohamed; Wang, Ling

2017-07-01

There have been plenty of studies intended to use different methods, for example, empirical Bayes before-after methods, to get accurate estimation of CMFs. All of them have different assumptions toward crash count if there was no treatment. Additionally, another major assumption is that multiple sites share the same true CMF. Under this assumption, the CMF at an individual intersection is randomly drawn from a normally distributed population of CMFs at all intersections. Since CMFs are non-zero values, the population of all CMFs might not follow normal distributions, and even if it does, the true mean of CMFs at some intersections may be different from that at others. Therefore, a bootstrap method based on before-after empirical Bayes theory was proposed to estimate CMFs, but it did not make distributional assumptions. This bootstrap procedure has the added benefit of producing a measure of CMF stability. Furthermore, based on the bootstrapped CMF, a new CMF precision rating method was proposed to evaluate the reliability of CMFs. This study chose 29 urban four-legged intersections as treated sites, and their controls were changed from stop-controlled to signal-controlled. Meanwhile, 124 urban four-legged stop-controlled intersections were selected as reference sites. At first, different safety performance functions (SPFs) were applied to five crash categories, and it was found that each crash category had different optimal SPF form. Then, the CMFs of these five crash categories were estimated using the bootstrap empirical Bayes method. The results of the bootstrapped method showed that signalization significantly decreased Angle+Left-Turn crashes, and its CMF had the highest precision. While, the CMF for Rear-End crashes was unreliable. For KABCO, KABC, and KAB crashes, their CMFs were proved to be reliable for the majority of intersections, but the estimated effect of signalization may be not accurate at some sites. Copyright © 2017 Elsevier Ltd. All rights reserved.

Emergency vehicle traffic signal preemption system

NASA Technical Reports Server (NTRS)

Bachelder, Aaron D. (Inventor); Foster, Conrad F. (Inventor)

2011-01-01

An emergency vehicle traffic light preemption system for preemption of traffic lights at an intersection to allow safe passage of emergency vehicles. The system includes a real-time status monitor of an intersection which is relayed to a control module for transmission to emergency vehicles as well as to a central dispatch office. The system also provides for audio warnings at an intersection to protect pedestrians who may not be in a position to see visual warnings or for various reasons cannot hear the approach of emergency vehicles. A transponder mounted on an emergency vehicle provides autonomous control so the vehicle operator can attend to getting to an emergency and not be concerned with the operation of the system. Activation of a priority-code (i.e. Code-3) situation provides communications with each intersection being approached by an emergency vehicle and indicates whether the intersection is preempted or if there is any conflict with other approaching emergency vehicles. On-board diagnostics handle various information including heading, speed, and acceleration sent to a control module which is transmitted to an intersection and which also simultaneously receives information regarding the status of an intersection. Real-time communications and operations software allow central and remote monitoring, logging, and command of intersections and vehicles.

Crash Models For Rural Intersections: Four-Lane By Two-Lane Stop-Controlled And Two-Lane By Two-Lane Signalized

DOT National Transportation Integrated Search

1999-10-01

This report describes the collection, analysis, and modeling of crash and roadway data for intersections on rural roads in California and Michigan for the years 1993-1995. Three classes of intersections are considered: (1) three-legged intersections ...

Analysis of rural intersection accidents caused by stop sign violation and failure to yield the right-of-way

DOT National Transportation Integrated Search

2000-09-01

The objectives of this study were to (1) identify the factors that contribute to accidents caused by failure to stop and failure to yield the right-of-way at rural two-way stop-controlled intersections on the state highway system, and (2) determine w...

Vehicle-based countermeasures for signal and stop sign violations. Task 1, Intersection control violation crash analyses. Task 2, Top-level system and human factors requirements

DOT National Transportation Integrated Search

2004-03-01

The report provides the first two major task reports for a study to develop performance specifications and perform supporting objective tests for a planned field operational test (FOT) of a vehicle-based countermeasure to intersection crashes associa...

Development of next generation intersection control.

DOT National Transportation Integrated Search

2013-03-01

A reservation-based autonomous intersection control system, named Autonomous Control of Urban : TrAffic (ACUTA), was developed as a part of this research effort. ACUTA allows centralized management : of autonomous vehicles within a certain distance f...

Increasing motorist compliance and caution at stop signs.

PubMed Central

Van Houten, R; Retting, R A

2001-01-01

This study evaluated strategies to improve motorist compliance and caution at three stop-sign-controlled intersections with a history of motor vehicle crashes. The primary intervention was a light-emitting diode (LED) sign that featured animated eyes scanning left and right to prompt drivers to look left and right for approaching traffic. Data were scored from videotape on the percentage of drivers coming to a complete stop and the percentage of drivers looking right before entering the intersection. Observational data were collected on the percentage of right-angle conflicts (defined as braking suddenly or swerving from the path to avoid an intersection crash). The introduction of the LED sign according to a multiple baseline across the three intersections was associated with an increase in the percentage of vehicles coming to a complete stop at all three intersections and a small increase in the percentage of drivers looking right before entering the intersections. Conflicts between vehicles on the major and minor road were also reduced following the introduction of the animated eyes prompt. PMID:11421311

Intersection Monitor for Traffic-Light-Preemption System

NASA Technical Reports Server (NTRS)

Bachelder, Aaron; Foster, Conrad

2006-01-01

The figure shows an intersection monitor that is a key subsystem of an emergency traffic-light-preemption system that could be any of the systems described in the three immediately preceding articles and in Systems Would Preempt Traffic Lights for Emergency Vehicles (NPO-30573), NASA Tech Briefs, Vol. 28, No. 10 (October 2004), page 36. This unit is so named because it is installed at an intersection, where it monitors the phases (in the sense of timing) of the traffic lights. The mode of operation of this monitor is independent of the type of traffic-light-controller hardware or software in use at the intersection. Moreover, the design of the monitor is such that (1) the monitor does not, by itself, affect the operation of the traffic- light controller and (2) in the event of a failure of the monitor, the trafficlight controller continues to function normally (albeit without preemption). The monitor is installed in series with the traffic-light controller at an intersection. The control signals of interest are monitored by use of high-impedance taps on affected control lines. These taps are fully isolated and further protected by high-voltage diodes that prevent any voltages or short circuits that arise within the monitor from affecting the controller. The signals from the taps are processed digitally and cleaned up by use of high-speed logic gates, and the resulting data are passed on to other parts of the traffic-light-preemption intersection subsystem. The data are compared continuously with data from vehicles and used to calculate timing for reliable preemption of the traffic lights. The pedestrian crossing at the intersection is also monitored, and pedestrians are warned not to cross during preemption.

Validation study - on-road evaluation of the Cooperative Intersection Collision Avoidance System - Stop Sign Assist sign : (CICAS-SSA Report #5).

DOT National Transportation Integrated Search

2009-11-01

The CICAS-SSA sign is a roadside driver support system that is intended to improve gap rejection at rural stop-controlled intersections. The CICAS-SSA system tracks vehicle locations on a major roadway and then displays a message to a driver on the m...

Bus Stops and Pedestrian-Motor Vehicle Collisions in Lima, Peru: A Matched Case-Control Study

PubMed Central

Quistberg, D. Alex; Koepsell, Thomas D.; Johnston, Brian D.; Boyle, Linda Ng; Miranda, J. Jaime; Ebel, Beth E.

2015-01-01

Objective To evaluate the relationship between bus stop characteristics and pedestrian-motor vehicle collisions. Design Matched case-control study where the units of study were pedestrian crossing. Setting Random sample of 11 police commissaries in Lima, Peru. Data collection occurred from February, 2011 to September, 2011. Participants 97 intersection cases representing 1,134 collisions and 40 mid-block cases representing 469 collisions that occurred between October, 2010 and January, 2011 and their matched controls. Main Exposures Presence of a bus stop and specific bus stop characteristics. Main Outcome Occurrence of a pedestrian-motor vehicle collision. Results Intersections with bus stops were three times more likely to have a pedestrian-vehicle collision (OR 3.28, 95% CI 1.53-7.03), relative to intersections without bus stops. Both formal and informal bus stops were associated with a higher odds of a collision at intersections (OR 6.23, 95% CI 1.76-22.0 and OR 2.98, 1.37-6.49). At mid-block sites, bus stops on a bus-dedicated transit lane were also associated with collision risk (OR 2.36, 95% CI 1.02-5.42). All bus stops were located prior to the intersection, contrary to practices in most high income countries. Conclusions In urban Lima, the presence of a bus stop was associated with a three-fold increase in risk of a pedestrian collision. The highly competitive environment among bus companies may provide an economic incentive for risky practices such as dropping off passengers in the middle of traffic and jockeying for position with other buses. Bus stop placement should be considered to improve pedestrian safety. PMID:24357516

Intersection life cycle cost comparison tool user guide version 1.0.

DOT National Transportation Integrated Search

2016-05-01

The Intersection Life Cycle Cost Comparison Tool User Guide was developed as part of North : Carolina Department of Transportation Research Project No. 201411: Evaluation of Life Cycle : Impacts of Intersection Control Type Selection. : This sprea...

Intelligent Intersection Traffic Control Laboratory Fact Sheet

DOT National Transportation Integrated Search

2006-07-27

The Intelligent Intersection 11:affic Control Laboratory (IITCL) is an outdoor facility that supports the Federal Highway Administration's (FHWA) various research programs and research activities conducted by other U.S. Department of 11:ansportation ...

Evaluation of Intersection Traffic Control Measures through Simulation

NASA Astrophysics Data System (ADS)

Asaithambi, Gowri; Sivanandan, R.

2015-12-01

Modeling traffic flow is stochastic in nature due to randomness in variables such as vehicle arrivals and speeds. Due to this and due to complex vehicular interactions and their manoeuvres, it is extremely difficult to model the traffic flow through analytical methods. To study this type of complex traffic system and vehicle interactions, simulation is considered as an effective tool. Application of homogeneous traffic models to heterogeneous traffic may not be able to capture the complex manoeuvres and interactions in such flows. Hence, a microscopic simulation model for heterogeneous traffic is developed using object oriented concepts. This simulation model acts as a tool for evaluating various control measures at signalized intersections. The present study focuses on the evaluation of Right Turn Lane (RTL) and Channelised Left Turn Lane (CLTL). A sensitivity analysis was performed to evaluate RTL and CLTL by varying the approach volumes, turn proportions and turn lane lengths. RTL is found to be advantageous only up to certain approach volumes and right-turn proportions, beyond which it is counter-productive. CLTL is found to be advantageous for lower approach volumes for all turn proportions, signifying the benefits of CLTL. It is counter-productive for higher approach volume and lower turn proportions. This study pinpoints the break-even points for various scenarios. The developed simulation model can be used as an appropriate intersection lane control tool for enhancing the efficiency of flow at intersections. This model can also be employed for scenario analysis and can be valuable to field traffic engineers in implementing vehicle-type based and lane-based traffic control measures.

Neighborhood Social Inequalities in Road Traffic Injuries: The Influence of Traffic Volume and Road Design

PubMed Central

Gauvin, Lise; Plante, Céline; Fournier, Michel; Morency, Catherine

2012-01-01

Objectives. We examined the extent to which differential traffic volume and road geometry can explain social inequalities in pedestrian, cyclist, and motor vehicle occupant injuries across wealthy and poor urban areas. Methods. We performed a multilevel observational study of all road users injured over 5 years (n = 19 568) at intersections (n = 17 498) in a large urban area (Island of Montreal, Canada). We considered intersection-level (traffic estimates, major roads, number of legs) and area-level (population density, commuting travel modes, household income) characteristics in multilevel Poisson regressions that nested intersections in 506 census tracts. Results. There were significantly more injured pedestrians, cyclists, and motor vehicle occupants at intersections in the poorest than in the richest areas. Controlling for traffic volume, intersection geometry, and pedestrian and cyclist volumes greatly attenuated the event rate ratios between intersections in the poorest and richest areas for injured pedestrians (−70%), cyclists (−44%), and motor vehicle occupants (−44%). Conclusions. Roadway environment can explain a substantial portion of the excess rate of road traffic injuries in the poorest urban areas. PMID:22515869

Modern traffic control devices to improve safety at rural intersections.

DOT National Transportation Integrated Search

2011-12-01

"Engineers with the Texas Department of Transportation (TxDOT) frequently make changes to traffic control devices : (TCDs) to improve intersection safety. To use available funds judiciously, engineers make incremental changes in : order to select the...

Cooperative intersection collision avoidance system limited to stop sign and traffic signal violations (CICAS-V).

DOT National Transportation Integrated Search

2008-09-30

The objective of the Cooperative Intersection Collision Avoidance System for Violations (CICAS-V) Project is to develop and field-test a comprehensive system to reduce the number of crashes at intersections due to violations of traffic control device...

Design of a rotary for an uncontrolled multi-leg intersection in Chennai, India

NASA Astrophysics Data System (ADS)

Vasantha Kumar, S.; Gulati, Himanshu; Arora, Shivam

2017-11-01

One way to control the traffic at busy intersections is to construct a roundabout or rotary intersection, which is a special type of at-grade intersection, where all converging vehicles are forced to move round a central island in clock-wise direction. The present study aims to design a rotary for an uncontrolled multi leg intersection located in Royapetah in Chennai, India. The intersection has five approach roads with two-way traffic in all the approach roads and there is no signal or traffic police to control the traffic at present and hence experiences traffic chaos during peak hours. In order to design the rotary, it is essential to have the information on traffic volumes coming from the approach roads. For this, a video data collection was carried out for a duration of eight hours from 7.30 am to 11.30 am and from 2.30 pm to 6.30 pm on a typical working day using a handycam from the terrace of an apartment building located near the intersection. During data extraction stage, each 5 min. traffic volume was extracted for all the five classes of vehicles considered and were converted to passenger car units (PCU). The analysis of traffic data showed that during peak hour from 4.45 pm to 5.45 pm, the proportion of weaving traffic, i.e., ratio of sum of crossing streams to the total traffic on the weaving section was found to be 0.81. According to Indian road congress (IRC) guidelines, this proportion can take any value between 0.4 and 1 and in the present study, the calculated value is found to be within the prescribed range. Using the calculated values of average entry width of the rotary and width & length of weaving section, the practical capacity of the rotary was found to be 3020 PCUs which is well above the observed traffic volume of 2665 PCUs.

Micro-simulation of vehicle conflicts involving right-turn vehicles at signalized intersections based on cellular automata.

PubMed

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. Copyright © 2013 Elsevier Ltd. All rights reserved.

Development of an in-vehicle intersection collision countermeasure

NASA Astrophysics Data System (ADS)

Pierowicz, John A.

1997-02-01

Intersection collisions constitute approximately twenty-six percent of all accidents in the United States. Because of their complexity, and demands on the perceptual and decision making abilities of the driver, intersections present an increased risk of collisions between automobiles. This situation provides an opportunity to apply advanced sensor and processing capabilities to prevent these collisions. A program to determine the characteristics of intersection collisions and identify potential countermeasures will be described. This program, sponsored by the National Highway Traffic Safety Administration, utilized accident data to develop a taxonomy of intersection crashes. This taxonomy was used to develop a concept for an intersection collision avoidance countermeasure. The concept utilizes in-vehicle position, dynamic status, and millimeter wave radar system and an in-vehicle computer system to provide inputs to an intersection collision avoidance algorithm. Detection of potential violation of traffic control device, or proceeding into the intersection with inadequate gap will lead to the presentation of a warning to the driver. These warnings are presented to the driver primarily via a head-up display and haptic feedback. Roadside to vehicle communication provides information regarding phased traffic signal information. Active control of the vehicle's brake and steering systems are described. Progress in the development of the systems will be presented along with the schedule of future activities.

Distributed traffic signal control using fuzzy logic

NASA Technical Reports Server (NTRS)

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.

Modeling the dynamics of driver's dilemma zone perception using machine learning methods for safer intersection control.

DOT National Transportation Integrated Search

2014-04-01

The "dilemma zone" (DZ) is defined as the area where drivers approaching a signalized intersection must decide to either proceed or stop at the onset of the yellow indication. Drivers that might perceive themselves to be too close to an intersection ...

Two low-cost safety concepts for two-way STOP-controlled, rural intersections on high-speed two-lane, two-way roadways.

DOT National Transportation Integrated Search

2008-09-01

The Federal Highway Administration (FHWA) Office of Safety has identified intersections as one of its safety focus areas. As part of the FHWA efforts to reduce intersection crashes and the related injuries and fatalities, two concepts have been ident...

Four-phase or two-phase signal plan? A study on four-leg intersection by cellular automaton simulations

NASA Astrophysics Data System (ADS)

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.

The safety of urban cycle tracks: a review of the literature.

PubMed

Thomas, Beth; DeRobertis, Michelle

2013-03-01

Cycling has to be a safe activity, and perceived as such, if bicycle trips by all populations are to increase and the public health benefits are to be realized. A key characteristic of developed countries with a high cycling mode share is their provision of cycle tracks--separated bikeways along city streets--on major routes. This literature review therefore sought to examine studies of cycle tracks from different countries in order elucidate the safety of these facilities relative to cycling in the street and to point to areas where further research is needed. The review indicates that one-way cycle tracks are generally safer at intersections than two-way and that, when effective intersection treatments are employed, constructing cycle tracks on busy streets reduces collisions and injuries. The evidence also suggests that, when controlling for exposure and including all collision types, building one-way cycle tracks reduces injury severity even when such intersection treatments are not employed. However, the extent of this effect has not been well examined, as very few studies both look at severity and control for exposure. Future studies of the safety of cycle tracks and associated intersection treatments should focus foremost on examining injury severity, while controlling for exposure. In the U.S., where the obesity epidemic and its health consequences and costs are well documented, the benefits of increased cycling should be a focus of research and policy development in order to provide the infrastructure needed to attract people to cycling while minimizing injuries. Copyright © 2013 Elsevier Ltd. All rights reserved.

Driving Parameters for Distributed and Centralized Air Transportation Architectures

NASA Technical Reports Server (NTRS)

Feron, Eric

2001-01-01

This report considers the problem of intersecting aircraft flows under decentralized conflict avoidance rules. Using an Eulerian standpoint (aircraft flow through a fixed control volume), new air traffic control models and scenarios are defined that enable the study of long-term airspace stability problems. Considering a class of two intersecting aircraft flows, it is shown that airspace stability, defined both in terms of safety and performance, is preserved under decentralized conflict resolution algorithms. Performance bounds are derived for the aircraft flow problem under different maneuver models. Besides analytical approaches, numerical examples are presented to test the theoretical results, as well as to generate some insight about the structure of the traffic flow after resolution. Considering more than two intersecting aircraft flows, simulations indicate that flow stability may not be guaranteed under simple conflict avoidance rules. Finally, a comparison is made with centralized strategies to conflict resolution.

A Feasibility Study on Crash Avoidance at Four-Way Stop-Sign-Controlled Intersections Using Wireless Sensor Networks

NASA Astrophysics Data System (ADS)

Kim, Do Hyun; Choi, Kyoung Ho; Kim, Kyeong Tae; Li, Ki Joune

In this letter, we propose a novel approach using wireless sensor networks (WSNs) to enhance the safety and efficiency of four-way stop-sign-controlled (FWSC) intersections. The proposed algorithm provides right of way (RoW) and crash avoidance information by means of an intelligent WSN system. The system is composed of magnetic sensors, embedded in the center of a lane, with relay nodes and a base station placed on the side of the road. The experimental results show that the vehicle detection accuracy is over 99% and the sensor node battery life expectancy is over 3 years for traffic of 5, 800 vehicles per day. For the traffic application we consider, a strong effect is observed as the projected conflict rate was reduced by 72% compared to an FWSC intersection operated with only driver perception.

Curvilinear approach to an intersection and visual detection of a collision.

PubMed

Berthelon, C; Mestre, D

1993-09-01

Visual motion perception plays a fundamental role in vehicle control. Recent studies have shown that the pattern of optical flow resulting from the observer's self-motion through a stable environment is used by the observer to accurately control his or her movements. However, little is known about the perception of another vehicle during self-motion--for instance, when a car driver approaches an intersection with traffic. In a series of experiments using visual simulations of car driving, we show that observers are able to detect the presence of a moving object during self-motion. However, the perception of the other car's trajectory appears to be strongly dependent on environmental factors, such as the presence of a road sign near the intersection or the shape of the road. These results suggest that local and global visual factors determine the perception of a car's trajectory during self-motion.

A comparison of safety benefits of pedestrian countdown signals with and without pushbuttons in Michigan.

PubMed

Boateng, Richard Atta; Kwigizile, Valerian; Oh, Jun-Seok

2018-04-11

This study evaluated the safety impacts of PCSs with and without pushbuttons based on pedestrian crashes and pedestrian injuries in Michigan. This study used ten years of intersection data: five years before PCSs were installed and five years after they were installed, along with a comparison group, to evaluate the crash impacts of PCSs: at 107 intersections the PCS had a pushbutton and at 96 it did not. At these intersections, and at their comparison sites (where no PCS was installed), crash data (from 2004-2016) were examined, along with traffic and geometric characteristics, population, education and poverty levels data. Intersections where PCSs with pushbuttons have been installed showed a 29 percent reduction in total pedestrian crashes and a 30 percent reduction in fatal/injury pedestrian crashes. Further, when considering only pedestrians age 65 and below, these respective reductions are 33 and 35 percent. Intersections with PCSs but without pushbuttons did not show any significant change in any type of pedestrian crash. Although the Manual of Uniform Traffic Control Devices (FHWA, 2009) requires the use of PCSs at new traffic signal installations, this study suggests a safety benefit of installing PCSs with pushbutton at signals where a PCS without a pushbutton is present.

Validating a driving simulator using surrogate safety measures.

PubMed

Yan, Xuedong; Abdel-Aty, Mohamed; Radwan, Essam; Wang, Xuesong; Chilakapati, Praveen

2008-01-01

Traffic crash statistics and previous research have shown an increased risk of traffic crashes at signalized intersections. How to diagnose safety problems and develop effective countermeasures to reduce crash rate at intersections is a key task for traffic engineers and researchers. This study aims at investigating whether the driving simulator can be used as a valid tool to assess traffic safety at signalized intersections. In support of the research objective, this simulator validity study was conducted from two perspectives, a traffic parameter (speed) and a safety parameter (crash history). A signalized intersection with as many important features (including roadway geometries, traffic control devices, intersection surroundings, and buildings) was replicated into a high-fidelity driving simulator. A driving simulator experiment with eight scenarios at the intersection were conducted to determine if the subjects' speed behavior and traffic risk patterns in the driving simulator were similar to what were found at the real intersection. The experiment results showed that speed data observed from the field and in the simulator experiment both follow normal distributions and have equal means for each intersection approach, which validated the driving simulator in absolute terms. Furthermore, this study used an innovative approach of using surrogate safety measures from the simulator to contrast with the crash analysis for the field data. The simulator experiment results indicated that compared to the right-turn lane with the low rear-end crash history record (2 crashes), subjects showed a series of more risky behaviors at the right-turn lane with the high rear-end crash history record (16 crashes), including higher deceleration rate (1.80+/-1.20 m/s(2) versus 0.80+/-0.65 m/s(2)), higher non-stop right-turn rate on red (81.67% versus 57.63%), higher right-turn speed as stop line (18.38+/-8.90 km/h versus 14.68+/-6.04 km/h), shorter following distance (30.19+/-13.43 m versus 35.58+/-13.41 m), and higher rear-end probability (9/59=0.153 versus 2/60=0.033). Therefore, the relative validity of driving simulator was well established for the traffic safety studies at signalized intersections.

40 CFR 81.182 - Northwest Maine Intrastate Air Quality Control Region.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Fort Kent Township and running due south to the intersection of the said line with the Aroostook... intersected by a line common to the northern boundary of Township No. 6, Phillips Town, Salem Township, and Freeman Township to the intersection of the said line with the Franklin-Somerset County boundary, which is...

40 CFR 81.182 - Northwest Maine Intrastate Air Quality Control Region.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Fort Kent Township and running due south to the intersection of the said line with the Aroostook... intersected by a line common to the northern boundary of Township No. 6, Phillips Town, Salem Township, and Freeman Township to the intersection of the said line with the Franklin-Somerset County boundary, which is...

From Cellular Attractor Selection to Adaptive Signal Control for Traffic Networks

PubMed Central

Tian, Daxin; Zhou, Jianshan; Sheng, Zhengguo; Wang, Yunpeng; Ma, Jianming

2016-01-01

The management of varying traffic flows essentially depends on signal controls at intersections. However, design an optimal control that considers the dynamic nature of a traffic network and coordinates all intersections simultaneously in a centralized manner is computationally challenging. Inspired by the stable gene expressions of Escherichia coli in response to environmental changes, we explore the robustness and adaptability performance of signalized intersections by incorporating a biological mechanism in their control policies, specifically, the evolution of each intersection is induced by the dynamics governing an adaptive attractor selection in cells. We employ a mathematical model to capture such biological attractor selection and derive a generic, adaptive and distributed control algorithm which is capable of dynamically adapting signal operations for the entire dynamical traffic network. We show that the proposed scheme based on attractor selection can not only promote the balance of traffic loads on each link of the network but also allows the global network to accommodate dynamical traffic demands. Our work demonstrates the potential of bio-inspired intelligence emerging from cells and provides a deep understanding of adaptive attractor selection-based control formation that is useful to support the designs of adaptive optimization and control in other domains. PMID:26972968

From Cellular Attractor Selection to Adaptive Signal Control for Traffic Networks.

PubMed

Tian, Daxin; Zhou, Jianshan; Sheng, Zhengguo; Wang, Yunpeng; Ma, Jianming

2016-03-14

The management of varying traffic flows essentially depends on signal controls at intersections. However, design an optimal control that considers the dynamic nature of a traffic network and coordinates all intersections simultaneously in a centralized manner is computationally challenging. Inspired by the stable gene expressions of Escherichia coli in response to environmental changes, we explore the robustness and adaptability performance of signalized intersections by incorporating a biological mechanism in their control policies, specifically, the evolution of each intersection is induced by the dynamics governing an adaptive attractor selection in cells. We employ a mathematical model to capture such biological attractor selection and derive a generic, adaptive and distributed control algorithm which is capable of dynamically adapting signal operations for the entire dynamical traffic network. We show that the proposed scheme based on attractor selection can not only promote the balance of traffic loads on each link of the network but also allows the global network to accommodate dynamical traffic demands. Our work demonstrates the potential of bio-inspired intelligence emerging from cells and provides a deep understanding of adaptive attractor selection-based control formation that is useful to support the designs of adaptive optimization and control in other domains.

Influences of motorcycle rider and driver characteristics and road environment on red light running behavior at signalized intersections.

PubMed

Jensupakarn, Auearree; Kanitpong, Kunnawee

2018-04-01

In Thailand, red light running is considered as one of the most dangerous behaviors at intersection. Red light running (RLR) behavior is the failure to obey the traffic control signal. However, motorcycle riders and car drivers who are running through red lights could be influenced by human factors or road environment at intersection. RLR could be advertent or inadvertent behavior influenced by many factors. Little research study has been done to evaluate the contributing factors influencing the red-light violation behavior. This study aims to determine the factors influencing the red light running behavior including human characteristics, physical condition of intersection, traffic signal operation, and traffic condition. A total of 92 intersections were observed in Chiang Mai, Nakhon Ratchasima, and Chonburi, the major provinces in each region of Thailand. In addition, the socio-economic characteristics of red light runners were obtained from self-reported questionnaire survey. The Binary Logistic Regression and the Multiple Linear Regression models were used to determine the characteristics of red light runners and the factors influencing rates of red light running respectively. The results from this study can help to understand the characteristics of red light runners and factors affecting them to run red lights. For motorcycle riders and car drivers, age, gender, occupation, driving license, helmet/seatbelt use, and the probability to be penalized when running the red light significantly affect RLR behavior. In addition, the results indicated that vehicle travelling direction, time of day, existence of turning lane, number of lanes, lane width, intersection sight distance, type of traffic signal pole, type of traffic signal operation, length of yellow time interval, approaching speed, distance from intersection warning sign to stop line, and pavement roughness significantly affect RLR rates. Copyright © 2018 Elsevier Ltd. All rights reserved.

Traffic-Light-Preemption Vehicle-Transponder Software Module

NASA Technical Reports Server (NTRS)

Bachelder, Aaron; Foster, Conrad

2005-01-01

A prototype wireless data-communication and control system automatically modifies the switching of traffic lights to give priority to emergency vehicles. The system, which was reported in several NASA Tech Briefs articles at earlier stages of development, includes a transponder on each emergency vehicle, a monitoring and control unit (an intersection controller) at each intersection equipped with traffic lights, and a central monitoring subsystem. An essential component of the system is a software module executed by a microcontroller in each transponder. This module integrates and broadcasts data on the position, velocity, acceleration, and emergency status of the vehicle. The position, velocity, and acceleration data are derived partly from the Global Positioning System, partly from deductive reckoning, and partly from a diagnostic computer aboard the vehicle. The software module also monitors similar broadcasts from other vehicles and from intersection controllers, informs the driver of which intersections it controls, and generates visible and audible alerts to inform the driver of any other emergency vehicles that are close enough to create a potential hazard. The execution of the software module can be monitored remotely and the module can be upgraded remotely and, hence, automatically

Tool Time: Gender and Students' Use of Tools, Control, and Authority.

ERIC Educational Resources Information Center

Jones, M. Gail; Brader-Araje, Laura; Carboni, Lisa Wilson; Carter, Glenda; Rua, Melissa J.; Banilower, Eric; Hatch, Holly

2000-01-01

Observes 16 students from five elementary science classes to examine how students use tools when constructing new knowledge during science instruction, how control of tools is actualized from pedagogical perspectives, how language and tool accessibility intersect, how gender intersects with tool use, and how competition for resources impacts…

Development of automated testing tools for traffic control signals and devices (NTCIP and security) phase 2 : [summary].

DOT National Transportation Integrated Search

2015-02-01

The metal cabinets that house traffic signal : controllers are a common sight at most : intersections in Florida. Traffic engineers use them : to time signal changes and facilitate the flow of : traffic through an intersection. At the core of this : ...

Gender, Ethnicity, and their Intersectionality in the Prediction of Smoking Outcome Expectancies in Regular Cigarette Smokers

PubMed Central

Aguirre, Claudia G.; Bello, Mariel S.; Pang, Raina D.; Andrabi, Nafeesa; Hendricks, Peter S.; Bluthenthal, Ricky N.; Leventhal, Adam M.

2016-01-01

The current study utilized the intersectionality framework to explore whether smoking outcome expectancies (i.e., cognitions about the anticipated effects of smoking) were predicted by gender and ethnicity, and the gender-by-ethnicity interaction. In a cross-sectional design, daily smokers from the general community [32.2% women; Non-Hispanic African American (N=175), Non-Hispanic White (N=109), or Hispanic (N=26)] completed self-report measures on smoking expectancies and other co-factors. Results showed that women reported greater negative reinforcement (i.e., anticipated smoking-induced negative affect reduction) and weight control (i.e., anticipated smoking-induced appetite/weight suppression) expectancies than men. Hispanic (vs. African American or White) smokers endorsed greater negative reinforcement expectancies. A gender by ethnicity interaction was found for weight control expectancies, such that White women reported greater weight control expectancies than White men, but no gender differences among African American and Hispanic smokers were found. Ethnicity, gender, and their intersectionality should be considered in smoking cessation programs to target smoking-related cognitions. PMID:26438665

Gender, Ethnicity, and Their Intersectionality in the Prediction of Smoking Outcome Expectancies in Regular Cigarette Smokers.

PubMed

Aguirre, Claudia G; Bello, Mariel S; Andrabi, Nafeesa; Pang, Raina D; Hendricks, Peter S; Bluthenthal, Ricky N; Leventhal, Adam M

2016-01-01

The current study utilized the intersectionality framework to explore whether smoking outcome expectancies (i.e., cognitions about the anticipated effects of smoking) were predicted by gender and ethnicity, and the gender-by-ethnicity interaction. In a cross-sectional design, daily smokers from the general community (32.2% women; non-Hispanic African American [n = 175], non-Hispanic White [n = 109], or Hispanic [n = 26]) completed self-report measures on smoking expectancies and other co-factors. Results showed that women reported greater negative reinforcement (i.e., anticipated smoking-induced negative affect reduction) and weight control (i.e., anticipated smoking-induced appetite/weight suppression) expectancies than men. Hispanic (vs. African American or White) smokers endorsed greater negative reinforcement expectancies. A gender-by-ethnicity interaction was found for weight control expectancies, such that White women reported greater weight control expectancies than White men, but no gender differences among African American and Hispanic smokers were found. These findings suggest that gender, ethnicity, and their intersectionality should be considered in research on cognitive mechanisms that may contribute to tobacco-related health disparities. © The Author(s) 2015.

Optical control of resonant light transmission for an atom-cavity system

NASA Astrophysics Data System (ADS)

Sharma, Arijit; Ray, Tridib; Sawant, Rahul V.; Sheikholeslami, G.; Rangwala, S. A.; Budker, D.

2015-04-01

We demonstrate the manipulation of transmitted light through an optical Fabry-Pérot cavity, built around a spectroscopy cell containing enriched rubidium vapor. Light resonant with the 87RbD2 (F =2 ,F =1 ) ↔F' manifold is controlled by the transverse intersection of the cavity mode by another resonant light beam. The cavity transmission can be suppressed or enhanced depending on the coupling of atomic states due to the intersecting beams. The extreme manifestation of the cavity-mode control is the precipitous destruction (negative logic switching) or buildup (positive logic switching) of the transmitted light intensity on intersection of the transverse control beam with the cavity mode. Both the steady-state and transient responses are experimentally investigated. The mechanism behind the change in cavity transmission is discussed in brief.

A new traffic control design method for large networks with signalized intersections

NASA Technical Reports Server (NTRS)

Leininger, G. G.; Colony, D. C.; Seldner, K.

1979-01-01

The paper presents a traffic control design technique for application to large traffic networks with signalized intersections. It is shown that the design method adopts a macroscopic viewpoint to establish a new traffic modelling procedure in which vehicle platoons are subdivided into main stream queues and turning queues. Optimization of the signal splits minimizes queue lengths in the steady state condition and improves traffic flow conditions, from the viewpoint of the traveling public. Finally, an application of the design method to a traffic network with thirty-three signalized intersections is used to demonstrate the effectiveness of the proposed technique.

A Cooperative Traffic Control of Vehicle–Intersection (CTCVI) for the Reduction of Traffic Delays and Fuel Consumption

PubMed Central

Li, Jinjian; Dridi, Mahjoub; El-Moudni, Abdellah

2016-01-01

The problem of reducing traffic delays and decreasing fuel consumption simultaneously in a network of intersections without traffic lights is solved by a cooperative traffic control algorithm, where the cooperation is executed based on the connection of Vehicle-to-Infrastructure (V2I). This resolution of the problem contains two main steps. The first step concerns the itinerary of which intersections are chosen by vehicles to arrive at their destination from their starting point. Based on the principle of minimal travel distance, each vehicle chooses its itinerary dynamically based on the traffic loads in the adjacent intersections. The second step is related to the following proposed cooperative procedures to allow vehicles to pass through each intersection rapidly and economically: on one hand, according to the real-time information sent by vehicles via V2I in the edge of the communication zone, each intersection applies Dynamic Programming (DP) to cooperatively optimize the vehicle passing sequence with minimal traffic delays so that the vehicles may rapidly pass the intersection under the relevant safety constraints; on the other hand, after receiving this sequence, each vehicle finds the optimal speed profiles with the minimal fuel consumption by an exhaustive search. The simulation results reveal that the proposed algorithm can significantly reduce both travel delays and fuel consumption compared with other papers under different traffic volumes. PMID:27999333

A Pilot Study of Pedestrians with Visual Impairments Detecting Traffic Gaps and Surges Containing Hybrid Vehicles

PubMed Central

Emerson, Robert Wall; Naghshineh, Koorosh; Hapeman, Julie; Wiener, William

2010-01-01

The increasing number of hybrid and quiet internal combustion engine vehicles may impact the travel abilities of pedestrians who are blind. Pedestrians who rely on auditory cues for structuring their travel may face challenges in making crossing decisions in the presence of quiet vehicles. This article describes results of initial studies looking at the crossing decisions of pedestrians who are blind at an uncontrolled crossing (no traffic control) and a light controlled intersection. The presence of hybrid vehicles was a factor in each situation. At the uncontrolled crossing, Toyota hybrids were most difficult to detect but crossing decisions were made more often in small gaps ended by a Honda hybrid. These effects were seen only at speed under 20 mph. At the light controlled intersection, parallel surges of traffic were most difficult to detect when made up only of a Ford Escape hybrid. Results suggest that more controlled studies of vehicle characteristics impacting crossing decisions of pedestrians who are blind are warranted. PMID:21379367

A Pilot Study of Pedestrians with Visual Impairments Detecting Traffic Gaps and Surges Containing Hybrid Vehicles.

PubMed

Emerson, Robert Wall; Naghshineh, Koorosh; Hapeman, Julie; Wiener, William

2011-03-01

The increasing number of hybrid and quiet internal combustion engine vehicles may impact the travel abilities of pedestrians who are blind. Pedestrians who rely on auditory cues for structuring their travel may face challenges in making crossing decisions in the presence of quiet vehicles. This article describes results of initial studies looking at the crossing decisions of pedestrians who are blind at an uncontrolled crossing (no traffic control) and a light controlled intersection. The presence of hybrid vehicles was a factor in each situation. At the uncontrolled crossing, Toyota hybrids were most difficult to detect but crossing decisions were made more often in small gaps ended by a Honda hybrid. These effects were seen only at speed under 20 mph. At the light controlled intersection, parallel surges of traffic were most difficult to detect when made up only of a Ford Escape hybrid. Results suggest that more controlled studies of vehicle characteristics impacting crossing decisions of pedestrians who are blind are warranted.

Live stop-controlled intersection data collection.

DOT National Transportation Integrated Search

2007-01-01

This report describes an experimental investigation performed at live intersections to gather infrastructure-based naturalistic driver approach behavior data. This data was collected and analyzed with the goal of understanding how drivers approach in...

An original traffic additional emission model and numerical simulation on a signalized road

NASA Astrophysics Data System (ADS)

Zhu, Wen-Xing; Zhang, Jing-Yu

2017-02-01

Based on VSP (Vehicle Specific Power) model traffic real emissions were theoretically classified into two parts: basic emission and additional emission. An original additional emission model was presented to calculate the vehicle's emission due to the signal control effects. Car-following model was developed and used to describe the traffic behavior including cruising, accelerating, decelerating and idling at a signalized intersection. Simulations were conducted under two situations: single intersection and two adjacent intersections with their respective control policy. Results are in good agreement with the theoretical analysis. It is also proved that additional emission model may be used to design the signal control policy in our modern traffic system to solve the serious environmental problems.

NOx profile around a signalized intersection of busy roadway

NASA Astrophysics Data System (ADS)

Kim, Kyung Hwan; Lee, Seung-Bok; Woo, Sung Ho; Bae, Gwi-Nam

2014-11-01

The NOx pollution profile around a signalized intersection of a busy roadway was investigated to understand the effect of traffic control on urban air pollution. Traffic flow patterns were classified into three categories of quasi-cruising, a combination of deceleration and acceleration, and a combination of deceleration, idling, and acceleration. The spatial distribution of air pollution levels around an intersection could be represented as a quasi-normal distribution, whose peak height was aggravated by increased emissions due to transient driving patterns. The peak concentration of NOx around the signalized intersection for the deceleration, idling, and acceleration category was five times higher than that for the quasi-cruising category. Severe levels of NOx pollution tailed off approximately 400 m from the center of the intersection. Approximately 200-1000 ppb of additional NOx was observed when traffic was decelerating, idling, and accelerating within the intersection zone, resulting in high exposure levels for pedestrians around the intersection. We propose a fluctuating horizontal distribution of motor vehicle-induced air pollutants as a function of time.

Intersection-Controller Software Module

NASA Technical Reports Server (NTRS)

Bachelder, Aaron; Foster, Conrad

2005-01-01

An important part of the emergency-vehicle traffic-light-preemption system summarized in the preceding article is a software module executed by a microcontroller in each intersection controller. This module monitors the broadcasts from all nearby participating emergency vehicles and intersections. It gathers the broadcast data pertaining to the positions and velocities of the vehicles and the timing of traffic and pedestrian lights and processes the data into predictions of the future positions of the vehicles. Analyzing the predictions by a combination of proximity tests, map-matching techniques, and statistical calculations designed to minimize the adverse effects of uncertainties in vehicle positions and headings, the module decides whether to preempt and issues the appropriate commands to the traffic lights, pedestrian lights, and electronic warning signs at the intersection. The module also broadcasts its state to all nearby vehicles and intersections. The module is designed to mitigate the effects of missing data and of unpredictable delays in the system. It has been intensively tested and refined so that it fails to warn in very few cases and issues very few false warnings.

Marginalized identities, discrimination burden, and mental health: empirical exploration of an interpersonal-level approach to modeling intersectionality.

PubMed

Seng, Julia S; Lopez, William D; Sperlich, Mickey; Hamama, Lydia; Reed Meldrum, Caroline D

2012-12-01

Intersectionality is a term used to describe the intersecting effects of race, class, gender, and other marginalizing characteristics that contribute to social identity and affect health. Adverse health effects are thought to occur via social processes including discrimination and structural inequalities (i.e., reduced opportunities for education and income). Although intersectionality has been well-described conceptually, approaches to modeling it in quantitative studies of health outcomes are still emerging. Strategies to date have focused on modeling demographic characteristics as proxies for structural inequality. Our objective was to extend these methodological efforts by modeling intersectionality across three levels: structural, contextual, and interpersonal, consistent with a social-ecological framework. We conducted a secondary analysis of a database that included two components of a widely used survey instrument, the Everyday Discrimination Scale. We operationalized a meso- or interpersonal-level of intersectionality using two variables, the frequency score of discrimination experiences and the sum of characteristics listed as reasons for these (i.e., the person's race, ethnicity, gender, sexual orientation, nationality, religion, disability or pregnancy status, or physical appearance). We controlled for two structural inequality factors (low education, poverty) and three contextual factors (high crime neighborhood, racial minority status, and trauma exposures). The outcome variables we modeled were posttraumatic stress disorder symptoms and a quality of life index score. We used data from 619 women who completed the Everyday Discrimination Scale for a perinatal study in the U.S. state of Michigan. Statistical results indicated that the two interpersonal-level variables (i.e., number of marginalized identities, frequency of discrimination) explained 15% of variance in posttraumatic stress symptoms and 13% of variance in quality of life scores, improving the predictive value of the models over those using structural inequality and contextual factors alone. This study's results point to instrument development ideas to improve the statistical modeling of intersectionality in health and social science research. Copyright © 2012 Elsevier Ltd. All rights reserved.

Modeling electric bicycle's lane-changing and retrograde behaviors

NASA Astrophysics Data System (ADS)

Tang, Tie-Qiao; Luo, Xiao-Feng; Zhang, Jian; Chen, Liang

2018-01-01

Recently, electric bicycle (EB) has been one important traffic tool due to its own merits. However, EB's motion behaviors (especially at a signalized/non-signalized intersection) are more complex than those of vehicle since it always has lane-changing and retrograde behaviors. In this paper, we propose a model to explore EB's lane-changing and retrograde behaviors on a road with a signalized intersection. The numerical results indicate that the proposed model can qualitatively describe each EB's lane-changing and retrograde behaviors near a signalized intersection, and that lane-changing and retrograde behaviors have prominent impacts on the signalized intersection (i.e., prominent jams and congestions occur). The above results show that EB should be controlled as a vehicle, i.e., lane-changing and retrograde behaviors at a signalized intersection should strictly be prohibited to improve the operational efficiency and traffic safety at the signalized intersection.

Safety and Convergence Analysis of Intersecting Aircraft Flows Under Decentralized Collision Avoidance

NASA Astrophysics Data System (ADS)

Dallal, Ahmed H.

Safety is an essential requirement for air traffic management and control systems. Aircraft are not allowed to get closer to each other than a specified safety distance, to avoid any conflicts and collisions between aircraft. Forecast analysis predicts a tremendous increase in the number of flights. Subsequently, automated tools are needed to help air traffic controllers resolve air born conflicts. In this dissertation, we consider the problem of conflict resolution of aircraft flows with the assumption that aircraft are flowing through a fixed specified control volume at a constant speed. In this regard, several centralized and decentralized resolution rules have been proposed for path planning and conflict avoidance. For the case of two intersecting flows, we introduce the concept of conflict touches, and a collaborative decentralized conflict resolution rule is then proposed and analyzed for two intersecting flows. The proposed rule is also able to resolved airborne conflicts that resulted from resolving another conflict via the domino effect. We study the safety conditions under the proposed conflict resolution and collision avoidance rule. Then, we use Lyapunov analysis to analytically prove the convergence of conflict resolution dynamics under the proposed rule. The analysis show that, under the proposed conflict resolution rule, the system of intersecting aircraft flows is guaranteed to converge to safe, conflict free, trajectories within a bounded time. Simulations are provided to verify the analytically derived conclusions and study the convergence of the conflict resolution dynamics at different encounter angles. Simulation results show that lateral deviations taken by aircraft in each flow, to resolve conflicts, are bounded, and aircraft converged to safe and conflict free trajectories, within a finite time.

Driving simulator evaluation of drivers' response to intersections with dynamic use of exit-lanes for left-turn.

PubMed

Zhao, Jing; Yun, Meiping; Zhang, H Michael; Yang, Xiaoguang

2015-08-01

With the worsening of urban traffic congestion in large cities around the world, researchers have been looking for unconventional designs and/or controls to squeeze more capacity out of intersections, the most common bottlenecks of the road network. One of these innovative intersection designs, known as the exit-lanes for left-turn (EFL), opens up exit-lanes to be used by left-turn traffic with the help of an additional traffic light installed at the median opening (the pre-signal). This paper studies how drivers respond to EFL intersections with a series of driving simulator experiments. In our experiments, 64 drivers were recruited and divided into two groups. One group is trained to use the EFL while the other group is not. In addition, four scenarios were considered with different sign and marking designs and traffic conditions in the experiments. Results indicate that drivers show certain amount of confusion and hesitation when encountering an EFL intersection for the first time. They can be overcome, however, by increasing exposure through driver education or by cue provided from other vehicles. Moreover, drivers unfamiliar with EFL operation can make a left turn using the conventional left-turn lanes as usual. The EFL operation is not likely to pose any serious safety risk of the intersection in real life operations. Copyright © 2015 Elsevier Ltd. All rights reserved.

AERIS : Eco-Vehicle Speed Control at Signalized Intersections Using I2V Communication

DOT National Transportation Integrated Search

2012-06-01

This report concentrates on a velocity advisory tool, or decision support system, for vehicles approaching an intersection using communication capabilities between the infrastructure and vehicles. The system uses available signal change information, ...

Evaluation of commercial video-based intersection signal actuation systems.

DOT National Transportation Integrated Search

2008-12-01

Video cameras and computer image processors have come into widespread use for the detection of : vehicles for signal actuation at controlled intersections. Video is considered both a cost-saving and : convenient alternative to conventional stop-line ...

Ab initio multiple spawning on laser-dressed states: a study of 1,3-cyclohexadiene photoisomerization via light-induced conical intersections

NASA Astrophysics Data System (ADS)

Kim, Jaehee; Tao, Hongli; Martinez, Todd J.; Bucksbaum, Phil

2015-08-01

We extend the ab initio multiple spawning method to include both field-free and field-induced nonadiabatic transitions. We apply this method to describe ultrafast pump-probe experiments of the photoinduced ring-opening of gas phase 1,3-cyclohexadiene. In the absence of a control field, nonadiabatic transitions mediated by a conical intersection (CoIn) lead to rapid ground state recovery with both 1,3-cyclohexadiene and ring-opened hexatriene products. However, application of a control field within the first 200 fs after photoexcitation results in suppression of the hexatriene product. We demonstrate that this is a consequence of population dumping prior to reaching the CoIn and further interpret this in terms of light-induced CoIns created by the control field.

The Intersection of Stalking and the Severity of Intimate Partner Abuse.

PubMed

Brady, Patrick Q; Hayes, Brittany E

2018-04-01

Using data from the Chicago Women's Health Risk Study (N = 464), this study examined the intersection of stalking and the severity of intimate partner abuse while controlling for previously identified risk factors of intimate partner homicide. Findings indicate that (a) victims of life-threatening abuse by an intimate partner were significantly more likely to experience stalking than victims of nonlethal abuse; (b) after controlling for key risk factors, stalking increased the risk of life-threatening abuse; and (c) threats to kill the victim if she left was the only significant stalking-related behavior that increased the risk for life-threatening abuse. In addition, an offender's prior record and a higher number of previous abusive incidents increased the risk of life-threatening abuse. Implications for prevention and future directions for research are discussed.

Crash rates at intersections.

DOT National Transportation Integrated Search

2003-08-01

The objective of this study were to develop a database of intersections, match traffic crashes to these intersections, calculate rates for intersections, and identify intersections with the highest crash rates. A procedure was used to: a) identify in...

Safety and driver behavior studies at multiple lane approaches to stop-controlled intersections.

DOT National Transportation Integrated Search

2010-05-01

Multiple-lane approaches (MLAs) controlled by stop signs are becoming increasingly common in Nebraska. Installation of MLAs occurs when a single approach lane can no longer adequately serve the minor road traffic volume, and a signal is unwarranted b...

Green cooperative adaptive control systems in the vicinity of signalized intersections.

DOT National Transportation Integrated Search

2014-10-01

Vehicle stops and speed variations account for a large percentage of vehicle fuel losses especially at signalized intersections. : Recently, researchers have attempted to develop tools that reduce these losses by capitalizing on traffic signal inform...

Research notes : should ODOT go roundabout : intersection control by going in circles?

DOT National Transportation Integrated Search

1998-07-16

Roundabouts have been used in foreign countries for decades, with several recently built in Florida, Maryland, Vermont and Colorado. The Oregon Department of Transportation (ODOT) is considering roundabouts as an alternative design for intersection c...

Control of Networked Traffic Flow Distribution - A Stochastic Distribution System Perspective

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Hong; Aziz, H M Abdul; Young, Stan

Networked traffic flow is a common scenario for urban transportation, where the distribution of vehicle queues either at controlled intersections or highway segments reflect the smoothness of the traffic flow in the network. At signalized intersections, the traffic queues are controlled by traffic signal control settings and effective traffic lights control would realize both smooth traffic flow and minimize fuel consumption. Funded by the Energy Efficient Mobility Systems (EEMS) program of the Vehicle Technologies Office of the US Department of Energy, we performed a preliminary investigation on the modelling and control framework in context of urban network of signalized intersections.more » In specific, we developed a recursive input-output traffic queueing models. The queue formation can be modeled as a stochastic process where the number of vehicles entering each intersection is a random number. Further, we proposed a preliminary B-Spline stochastic model for a one-way single-lane corridor traffic system based on theory of stochastic distribution control.. It has been shown that the developed stochastic model would provide the optimal probability density function (PDF) of the traffic queueing length as a dynamic function of the traffic signal setting parameters. Based upon such a stochastic distribution model, we have proposed a preliminary closed loop framework on stochastic distribution control for the traffic queueing system to make the traffic queueing length PDF follow a target PDF that potentially realizes the smooth traffic flow distribution in a concerned corridor.« less

Turning movements, vehicle offsets and ageing drivers driving behaviour at channelized and unchannelized intersections.

PubMed

Choi, Jaisung; Tay, Richard; Kim, Sangyoup; Jeong, Seungwon

2017-11-01

Ageing drivers experience a higher risk of intersection crashes because of their decrease in driving efficiency, including the decline in cognitive ability, head and neck flexibility, and visual acuity. Although several studies have been conducted to examine the factors associated with ageing driver crashes at intersections, little research has been conducted to examine the differences in the factors related to ageing drivers' turning paths and intersection geometric features. This study aims to improve the safety of ageing drivers at intersections by identifying the maneuvers that are risky for them and tracking their turning movements at selected intersections. We find that ageing drivers experience more crashes at intersections than younger drivers, especially crashes involving turning movements. Furthermore, ageing drivers experience more crashes at unchannelized intersections compared to channelized intersections. In addition, this study finds that ageing drivers exhibit greater and more inconsistent offsets during turning movements compared to those of younger drivers at both channelized and unchannelized intersections. Ageing drivers also tend to make relatively sharper or tighter turns than younger drivers. Hence, transportation engineers and road safety professionals should consider appropriate countermeasures to reduce the risks of crashes involving ageing drivers at intersections. Copyright © 2017 Elsevier Ltd. All rights reserved.

Development and preliminary testing of an automatic turning movements identification system : final report, February 2010.

DOT National Transportation Integrated Search

2010-02-01

It is important for many applications, such as intersection delay estimation and adaptive signal : control, to obtain vehicle turning movement information at signalized intersections. However, : vehicle turning movement information is very time consu...

An integrated computer system for analysis, selection, and evaluation of unconventional intersections.

DOT National Transportation Integrated Search

2011-03-01

The emergence of unconventional intersections in the traffic community has been motivated by the notion : of improving service quality with innovative control strategies, such as rerouting the turning movements : or flipping the paths of two traffic ...

Variable cycle control model for intersection based on multi-source information

NASA Astrophysics Data System (ADS)

Sun, Zhi-Yuan; Li, Yue; Qu, Wen-Cong; Chen, Yan-Yan

2018-05-01

In order to improve the efficiency of traffic control system in the era of big data, a new variable cycle control model based on multi-source information is presented for intersection in this paper. Firstly, with consideration of multi-source information, a unified framework based on cyber-physical system is proposed. Secondly, taking into account the variable length of cell, hysteresis phenomenon of traffic flow and the characteristics of lane group, a Lane group-based Cell Transmission Model is established to describe the physical properties of traffic flow under different traffic signal control schemes. Thirdly, the variable cycle control problem is abstracted into a bi-level programming model. The upper level model is put forward for cycle length optimization considering traffic capacity and delay. The lower level model is a dynamic signal control decision model based on fairness analysis. Then, a Hybrid Intelligent Optimization Algorithm is raised to solve the proposed model. Finally, a case study shows the efficiency and applicability of the proposed model and algorithm.

A computerized traffic control algorithm to determine optimal traffic signal settings. Ph.D. Thesis - Toledo Univ.

NASA Technical Reports Server (NTRS)

Seldner, K.

1977-01-01

An algorithm was developed to optimally control the traffic signals at each intersection using a discrete time traffic model applicable to heavy or peak traffic. Off line optimization procedures were applied to compute the cycle splits required to minimize the lengths of the vehicle queues and delay at each intersection. The method was applied to an extensive traffic network in Toledo, Ohio. Results obtained with the derived optimal settings are compared with the control settings presently in use.

Safety, operational, and energy impacts of in-vehicle adaptive stop displays using connected vehicle technology.

DOT National Transportation Integrated Search

2015-07-01

Un-signalized intersections create multiple opportunities for missed or misunderstood information. : Stop sign-controlled intersections have also been shown to be a source of delay and emissions due : to their frequent, often inappropriate use. By us...

Traffic Predictive Control: Case Study and Evaluation

DOT National Transportation Integrated Search

2017-06-26

This project developed a quantile regression method for predicting future traffic flow at a signalized intersection by combining both historical and real-time data. The algorithm exploits nonlinear correlations in historical measurements and efficien...

Marginalized identities, discrimination burden, and mental health: Empirical exploration of an interpersonal-level approach to modeling intersectionality

PubMed Central

Seng, Julia S; Lopez, William D; Sperlich, Mickey; Hamama, Lydia; Meldrum, Caroline D Reed

2012-01-01

Intersectionality is a term used to describe the intersecting effects of race, class, gender, and other marginalizing characteristics that contribute to social identity and affect health. Adverse health effects are thought to occur via social processes including discrimination and structural inequalities (i.e., reduced opportunities for education and income). Although intersectionality has been well-described conceptually, approaches to modeling it in quantitative studies of health outcomes are still emerging. Strategies to date have focused on modeling demographic characteristics as proxies for structural inequality. Our objective was to extend these methodological efforts by modeling intersectionality across three levels: structural, contextual, and interpersonal, consistent with a social-ecological framework. We conducted a secondary analysis of a database that included two components of a widely used survey instrument, the Everyday Discrimination Scale. We operationalized a meso- or interpersonal-level of intersectionality using two variables, the frequency score of discrimination experiences and the sum of characteristics listed as reasons for these (i.e., the person’s race, ethnicity, gender, sexual orientation, nationality, religion, disability or pregnancy status, or physical appearance). We controlled for two structural inequality factors (low education, poverty) and three contextual factors (high crime neighborhood, racial minority status, and trauma exposures). The outcome variables we modeled were posttraumatic stress disorder symptoms and a quality of life index score. We used data from 619 women who completed the Everyday Discrimination Scale for a perinatal study in the U.S. state of Michigan. Statistical results indicated that the two interpersonal-level variables (i.e., number of marginalized identities, frequency of discrimination) explained 15% of variance in posttraumatic stress symptoms and 13% of variance in quality of life scores, improving the predictive value of the models over those using structural inequality and contextual factors alone. This study’s results point to instrument development ideas to improve the statistical modeling of intersectionality in health and social science research. PMID:23089613

Development and Evaluation of Lane-By-Lane Gap-Out Based Actuated Traffic Signal Control

DOT National Transportation Integrated Search

2012-09-01

Actuated traffic signal controls at isolated intersections largely benefit from gap-out and phase skip features as they allow : unused green times to be re-allocated to those movements need them. A few studies indicated that lane-by-lane gap-out : sh...

Age-Related Differences in Vehicle Control and Eye Movement Patterns at Intersections: Older and Middle-Aged Drivers

PubMed Central

Yamani, Yusuke; Horrey, William J.; Liang, Yulan; Fisher, Donald L.

2016-01-01

Older drivers are at increased risk of intersection crashes. Previous work found that older drivers execute less frequent glances for detecting potential threats at intersections than middle-aged drivers. Yet, earlier work has also shown that an active training program doubled the frequency of these glances among older drivers, suggesting that these effects are not necessarily due to age-related functional declines. In light of findings, the current study sought to explore the ability of older drivers to coordinate their head and eye movements while simultaneously steering the vehicle as well as their glance behavior at intersections. In a driving simulator, older (M = 76 yrs) and middle-aged (M = 58 yrs) drivers completed different driving tasks: (1) travelling straight on a highway while scanning for peripheral information (a visual search task) and (2) navigating intersections with areas potential hazard. The results replicate that the older drivers did not execute glances for potential threats to the sides when turning at intersections as frequently as the middle-aged drivers. Furthermore, the results demonstrate costs of performing two concurrent tasks, highway driving and visual search task on the side displays: the older drivers performed more poorly on the visual search task and needed to correct their steering positions more compared to the middle-aged counterparts. The findings are consistent with the predictions and discussed in terms of a decoupling hypothesis, providing an account for the effects of the active training program. PMID:27736887

GIS-based intersection inventory system (GIS-IIS) : integrating GIS, traffic signal data and intersection images

DOT National Transportation Integrated Search

2005-02-25

This study developed a GIS-based Intersection Inventory System (GIS-IIS) for the signalized : intersections on the state-maintained highway system of IDOT District 6. GIS-IIS is a tool to have an : easy access to intersection inventory data, photogra...

Exposure to lateral collision in signalized intersections with protected left turn under different traffic control strategies.

PubMed

Midenet, Sophie; Saunier, Nicolas; Boillot, Florence

2011-11-01

This paper proposes an original definition of the exposure to lateral collision in signalized intersections and discusses the results of a real world experiment. This exposure is defined as the duration of situations where the stream that is given the right-of-way goes through the conflict zone while road users are waiting in the cross-traffic approach. This measure, obtained from video sensors, makes it possible to compare different operating conditions such as different traffic signal strategies. The data from a real world experiment is used, where the adaptive real-time strategy CRONOS (ContRol Of Networks by Optimization of Switchovers) and a time-plan strategy with vehicle-actuated ranges alternately controlled an isolated intersection near Paris. Hourly samples with similar traffic volumes are compared and the exposure to lateral collision is different in various areas of the intersection and various traffic conditions for the two strategies. The total exposure under peak hour traffic conditions drops by roughly 5 min/h with the CRONOS strategy compared to the time-plan strategy, which occurs mostly on entry streams. The results are analyzed through the decomposition of cycles in phase sequences and recommendations are made for traffic control strategies. Copyright © 2011 Elsevier Ltd. All rights reserved.

Safety evaluation of flashing beacons at STOP-controlled intersections

DOT National Transportation Integrated Search

2008-03-01

The Federal Highway Administration (FHWA) organized a pooled fund study of 26 States to evaluate low-cost safety strategies as part of its strategic highway safety effort. One of the strategies chosen to be evaluated for this study was flashing beaco...

Safety evaluation of flashing beacons at stop-controlled intersections

DOT National Transportation Integrated Search

2008-03-01

The Federal Highway Administration (FHWA) organized 26 States to participate in the FHWA Low-Cost Safety Improvements Pooled Fund Study as part of its strategic highway safety plan support effort. The purpose of the study is to evaluate the safety ef...

Developing a short range vehicle to infrastructure communication system to enhance the safety at STOP sign intersections : final report.

DOT National Transportation Integrated Search

2016-05-01

Stop sign controlled unsignalized intersections raise a public safe concern. Even though various strategies, such as engineering, education, and policy, have been applied in practice, there are a number of fatal crashes occurred at unsignalized inter...

Microwave waveguide manifold and method

DOEpatents

Staehlin, John H.

1987-01-01

A controllably electrically coupled, physically intersecting plural waveguide manifold assembly wherein the intersecting waveguide elements are fabricated in integral unitary relationship from a single piece of metal in order to avoid the inaccuracies and difficult-to-control fabrication steps associated with uniting separate waveguide elements into a unitary structure. An X-band aluminum airborne radar manifold example is disclosed, along with a fabrication sequence for the manifold and the electrical energy communicating apertures joining the manifold elements.

Microwave waveguide manifold and method

DOEpatents

Staehlin, John H.

1987-12-01

A controllably electrically coupled, physically intersecting plural waveguide manifold assembly wherein the intersecting waveguide elements are fabricated in integral unitary relationship from a single piece of metal in order to avoid the inaccuracies and difficult-to-control fabrication steps associated with uniting separate waveguide elements into a unitary structure. An X-band aluminum airborne radar manifold example is disclosed, along with a fabrication sequence for the manifold and the electrical energy communicating apertures joining the manifold elements.

Factors affecting fuel break effectiveness in the control of large fires on the Los Padres National Forest, California

USGS Publications Warehouse

Syphard, Alexandra D.; Keeley, Jon E.; Brennan, Teresa J.

2011-01-01

As wildfires have increased in frequency and extent, so have the number of homes developed in the wildland-urban interface. In California, the predominant approach to mitigating fire risk is construction of fuel breaks, but there has been little empirical study of their role in controlling large fires.We constructed a spatial database of fuel breaks on the Los Padres National Forest in southern California to better understand characteristics of fuel breaks that affect the behaviour of large fires and to map where fires and fuel breaks most commonly intersect. We evaluated whether fires stopped or crossed over fuel breaks over a 28-year period and compared the outcomes with physical characteristics of the sites, weather and firefighting activities during the fire event. Many fuel breaks never intersected fires, but others intersected several, primarily in historically fire-prone areas. Fires stopped at fuel breaks 46% of the time, almost invariably owing to fire suppression activities. Firefighter access to treatments, smaller fires and longer fuel breaks were significant direct influences, and younger vegetation and fuel break maintenance indirectly improved the outcome by facilitating firefighter access. This study illustrates the importance of strategic location of fuel breaks because they have been most effective where they provided access for firefighting activities.

Using the event analysis of systemic teamwork (EAST) to explore conflicts between different road user groups when making right hand turns at urban intersections.

PubMed

Salmon, Paul M; Lenne, Michael G; Walker, Guy H; Stanton, Neville A; Filtness, Ashleigh

2014-01-01

Collisions between different types of road users at intersections form a substantial component of the road toll. This paper presents an analysis of driver, cyclist, motorcyclist and pedestrian behaviour at intersections that involved the application of an integrated suite of ergonomics methods, the Event Analysis of Systemic Teamwork (EAST) framework, to on-road study data. EAST was used to analyse behaviour at three intersections using data derived from an on-road study of driver, cyclist, motorcyclist and pedestrian behaviour. The analysis shows the differences in behaviour and cognition across the different road user groups and pinpoints instances where this may be creating conflicts between different road users. The role of intersection design in creating these differences in behaviour and resulting conflicts is discussed. It is concluded that currently intersections are not designed in a way that supports behaviour across the four forms of road user studied. Interventions designed to improve intersection safety are discussed. Practitioner Summary: Intersection safety currently represents a key road safety issue worldwide. This paper presents a novel application of a framework of ergonomics methods for studying differences in road user behaviour at intersections. The findings support development of interventions that consider all road users as opposed to one group in isolation.

Information Points and Optimal Discharging Speed: Effects on the Saturation Flow at Signalized Intersections

ERIC Educational Resources Information Center

Gao, Lijun

2015-01-01

An information point was defined in this study as any object, structure, or activity located outside of a traveling vehicle that could potentially attract the visual attention of the driver. Saturation flow rates were studied for three pairs of signalized intersections in Toledo, Ohio. Each pair of intersections consisted of one intersection with…

A junction-tree based learning algorithm to optimize network wide traffic control: A coordinated multi-agent framework

DOE PAGES

Zhu, Feng; Aziz, H. M. Abdul; Qian, Xinwu; ...

2015-01-31

Our study develops a novel reinforcement learning algorithm for the challenging coordinated signal control problem. Traffic signals are modeled as intelligent agents interacting with the stochastic traffic environment. The model is built on the framework of coordinated reinforcement learning. The Junction Tree Algorithm (JTA) based reinforcement learning is proposed to obtain an exact inference of the best joint actions for all the coordinated intersections. Moreover, the algorithm is implemented and tested with a network containing 18 signalized intersections in VISSIM. Finally, our results show that the JTA based algorithm outperforms independent learning (Q-learning), real-time adaptive learning, and fixed timing plansmore » in terms of average delay, number of stops, and vehicular emissions at the network level.« less

Effects of digital countdown timer on intersection safety and efficiency: A systematic review.

PubMed

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.

Tracer Flux Balance at an Urban Canyon Intersection

NASA Astrophysics Data System (ADS)

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.

Droplet Sizing Research.

DTIC Science & Technology

1985-04-15

studies, The measurement volume is defined by the intersection aerosol studies, flue gas desulfurization , spray drying, of apertures in front of two...identify by block numberl --A method to measure the size and velocity of individual particles in a flow is discussed. Results are presented for controlled ... controlled m0 monodisperse sprays and compared to flash photographs. Typical errors between predicted and measured sizes are less than 5%. Experimental

Agent-based traffic management and reinforcement learning in congested intersection network.

DOT National Transportation Integrated Search

2012-08-01

This study evaluates the performance of traffic control systems based on reinforcement learning (RL), also called approximate dynamic programming (ADP). Two algorithms have been selected for testing: 1) Q-learning and 2) approximate dynamic programmi...

Intersectionality, Race-Gender Subordination, and Education

ERIC Educational Resources Information Center

Harris, Angela; Leonardo, Zeus

2018-01-01

In this chapter, we unpack "intersectionality as an analytical framework." First, we cite Black Lives Matter as an impetus for discussing intersectionality's current traction. Second, we review the genealogy of "intersectionality" beginning with Kimberlé Crenshaw's formulation, which brought a Black Studies provocation into…

Roundabout performance analysis in the city of Medan

NASA Astrophysics Data System (ADS)

Surbakti, M.; Iswahyudi, F.

2018-02-01

Medan city as one of the largest cities in Indonesia, currently has problems in the field of transport is quite worrying. Like the other cities in Indonesia, the growth of traffic volume can not be followed by improvement of existing infrastructure. It is characterized by frequent traffic jams, long queues and delays contained in the segment or intersection. One type of arrangement is a roundabout intersection. Roundabout intersection canalization is composed of a central circle surrounded by a one-way street. Roundabout can act as a controller, divider and guidance for the traffic system which rotates in the direction. This study aims to determine the performance of the roundabout on the road Ir. Haji Juanda, Medan. Analyses were performed to obtain the performance of these intersections. Analyses were performed by using a calculation method MKJI 1997 and the Australian Road Research Board (ARRB) manually. The performance measures analyzed in the form of the degree of saturation, delay and queue opportunities using the method MKJI 1997. whereas the ARRB method, the calculated performance of the roundabout is the degree of saturation and delay. Good infrastructure handling can create a reduction of delay, and congestion, so that it can reduce pollution and support a more green environment.

Intersectional perspective in elderly care.

PubMed

Cuesta, Marta; Rämgård, Margareta

2016-01-01

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's self-confidence, in a positive way.

Intersectional perspective in elderly care

PubMed Central

Cuesta, Marta; Rämgård, Margareta

2016-01-01

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's self-confidence, in a positive way. PMID:27167554

Landscaping of highway medians and roadway safety at unsignalized intersections.

PubMed

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. Copyright © 2016. Published by Elsevier Ltd.

Predicting crash-relevant violations at stop sign-controlled intersections for the development of an intersection driver assistance system.

PubMed

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 some time for detecting violations but was able to substantially reduce false alarms to only 3.3% of all nonviolating approaches. Given good surface conditions (maximum braking capabilities = 0.8 g) and maximum effort, most drivers (55.3-71.1%) would be able to stop the vehicle regardless of the detection algorithm. However, given poor surface conditions (maximum braking capabilities = 0.4 g), few drivers (10.5-26.3%) would be able to stop the vehicle. Automatic emergency braking (AEB) would allow for early braking prior to driver reaction. If equipped with an AEB system, the results suggest that, even for the poor surface conditions scenario, over one half (55.3-65.8%) of the vehicles could have been stopped. This study demonstrates the potential of I-ADAS to incorporate a stop sign violation detection algorithm. Repeating the analysis on a larger, more extensive data set will allow for the development of a more comprehensive algorithm to further validate the findings.

Stability of distributed MPC in an intersection scenario

NASA Astrophysics Data System (ADS)

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.

Evaluation of the cost-effectiveness of illumination as a safety treatment at rural intersections.

DOT National Transportation Integrated Search

2016-09-01

This research study seeks to improve current understanding of the relationship between rural intersection safety and different illumination levels. It uses three parallel studies: a survey of rural intersection illumination practices among US state d...

Evaluation of intersection countermeasures on high-speed rural multi-lane facilities.

DOT National Transportation Integrated Search

2012-01-01

The primary objective of this study is the evaluation of the effectiveness of several proposed safety : treatments at two intersections in Habersham County, Georgia. The intersections selected for this study had high : crash rates leading to a Georgi...

Field-effect Flow Control in Polymer Microchannel Networks

NASA Technical Reports Server (NTRS)

Sniadecki, Nathan; Lee, Cheng S.; Beamesderfer, Mike; DeVoe, Don L.

2003-01-01

A new Bio-MEMS electroosmotic flow (EOF) modulator for plastic microchannel networks has been developed. The EOF modulator uses field-effect flow control (FEFC) to adjust the zeta potential at the Parylene C microchannel wall. By setting a differential EOF pumping rate in two of the three microchannels at a T-intersection with EOF modulators, the induced pressure at the intersection generated pumping in the third, field-free microchannel. The EOF modulators are able to change the magnitude and direction of the pressure pumping by inducing either a negative or positive pressure at the intersection. The flow velocity is tracked by neutralized fluorescent microbeads in the microchannels. The proof-of-concept of the EOF modulator described here may be applied to complex plastic ,microchannel networks where individual microchannel flow rates are addressable by localized induced-pressure pumping.

Ecohydrology of an outbreak: Mountain pine beetle impacts trees in drier landscape positions first

Treesearch

Kendra E. Kaiser; Ryan E. Emanuel

2013-01-01

Vegetation pattern and landscape structure intersect to exert strong control over ecohydrological dynamics at the watershed scale. The hydrologic implications of vegetation disturbance (e.g. fire, disease) depend on the spatial pattern and form of environmental change. Here, we investigate this intersection at Tenderfoot Creek Experimental Forest (TCEF), Montana, with...

An intelligent traffic controller

DOT National Transportation Integrated Search

1995-11-01

Advances in computing sciences have not been applied to traffic control. This paper describes the development of an intelligent controller. A controller with advanced control logic can significantly improve traffic flows at intersections. In this vei...

Research notes : adjustment of driver behavior to an urban multilane roundabout.

DOT National Transportation Integrated Search

2007-06-01

In June of 2006, the City of Springfield, Oregon began construction of the first multi-lane urban roundabout in Oregon. The five-legged roundabout replaced an existing T intersection that was controlled by a traffic light. A study was conducted...

National occupant protection use survey 2000 : controlled intersection study

DOT National Transportation Integrated Search

2001-08-01

In the Fall of 2000, 21 percent more Young Adults (persons 16 24 years of age) were restrained by shoulder belts than were restrained in the Fall of 1998. These estimates were obtained through the National Occupant Protection Use Survey (NOPUS) which...

National occupant protection use survey : controlled intersection detailed study

DOT National Transportation Integrated Search

1997-02-01

In late 1994, NHTSA conducted the first National Occupant Protection Use Survey : (NOPUS). Shoulder belt use was observed at a random sample of sites across the : country for drivers and right-front passengers of cars and light trucks. In one : porti...

Safety analysis of urban signalized intersections under mixed traffic.

PubMed

S, Anjana; M V L R, Anjaneyulu

2015-02-01

This study examined the crash causative factors of signalized intersections under mixed traffic using advanced statistical models. Hierarchical Poisson regression and logistic regression models were developed to predict the crash frequency and severity of signalized intersection approaches. The prediction models helped to develop general safety countermeasures for signalized intersections. The study shows that exclusive left turn lanes and countdown timers are beneficial for improving the safety of signalized intersections. Safety is also influenced by the presence of a surveillance camera, green time, median width, traffic volume, and proportion of two wheelers in the traffic stream. The factors that influence the severity of crashes were also identified in this study. As a practical application, the safe values of deviation of green time provided from design green time, with varying traffic volume, is presented in this study. This is a useful tool for setting the appropriate green time for a signalized intersection approach with variations in the traffic volume. Copyright © 2014 Elsevier Ltd. All rights reserved.

Traffic Feasibility Study for a Grade Separator at a Busy Intersection in Vellore

NASA Astrophysics Data System (ADS)

Vasantha Kumar, S.; Gulati, Himanshu; Arora, Shivam

2017-11-01

One of the byproduct of urbanization is traffic congestion and before suggesting any solutions to reduce congestion, understanding the present context becomes very important. Study of traffic volumes at busy intersections to find the percentage composition of different vehicle types, directional distribution and peak hour traffic volume is a first step towards understanding the present context of traffic. Hence in the present study, one of the busy intersections in Vellore, namely, Gandhi nagar intersection in Vellore-Katpadi road was selected and traffic flow data was collected using video surveys. It was found that at the selected intersection, the two wheelers and three wheelers alone share 80% of the total traffic when compared to other vehicle types. Nearly 700 trucks and multi axle trailers were observed to pass through the intersection during the analysis period of five hours. That is, on an average 2 trucks/multi axle trailers were passing through the intersection in each minute. As like in other major cities, entry of trucks and other heavy vehicles such as multi axle trailers into the city needs to be banned during peak hours for smooth flow of traffic within city limits. A highest hourly volume of 6939 PCU’s was observed between 4 and 5 pm at the selected intersection. By assuming a 10% uniform traffic growth every year, it was found that after about 4 years, i.e., in 2019, the traffic volume at the intersection may reach 10,000 PCU’s and may warrant for a grade separator or interchange at the intersection.

An Intersectional Perspective on Access to HIV-Related Healthcare for Transgender Women

PubMed Central

Lacombe-Duncan, Ashley

2016-01-01

Abstract Transgender women experience decreased access to HIV-related healthcare relative to cisgender people, in part due to pervasive transphobia in healthcare. This perspective describes intersectionality as a salient theoretical approach to understanding this disparity, moving beyond transphobia to explore how intersecting systems of oppression, including cisnormativity, sexism/transmisogyny, classism, racism, and HIV-related, gender nonconformity, substance use, and sex work stigma influence HIV-related healthcare access for transgender women living with HIV. This perspective concludes with a discussion of how intersectionality-informed studies can be enhanced through studying underexplored intersections and bringing attention to women's resiliency and empowerment. PMID:29159304

Effects of red light camera enforcement on fatal crashes in large U.S. cities.

PubMed

Hu, Wen; McCartt, Anne T; Teoh, Eric R

2011-08-01

To estimate the effects of red light camera enforcement on per capita fatal crash rates at intersections with signal lights. From the 99 large U.S. cities with more than 200,000 residents in 2008, 14 cities were identified with red light camera enforcement programs for all of 2004-2008 but not at any time during 1992-1996, and 48 cities were identified without camera programs during either period. Analyses compared the citywide per capita rate of fatal red light running crashes and the citywide per capita rate of all fatal crashes at signalized intersections during the two study periods, and rate changes then were compared for cities with and without cameras programs. Poisson regression was used to model crash rates as a function of red light camera enforcement, land area, and population density. The average annual rate of fatal red light running crashes declined for both study groups, but the decline was larger for cities with red light camera enforcement programs than for cities without camera programs (35% vs. 14%). The average annual rate of all fatal crashes at signalized intersections decreased by 14% for cities with camera programs and increased slightly (2%) for cities without cameras. After controlling for population density and land area, the rate of fatal red light running crashes during 2004-2008 for cities with camera programs was an estimated 24% lower than what would have been expected without cameras. The rate of all fatal crashes at signalized intersections during 2004-2008 for cities with camera programs was an estimated 17% lower than what would have been expected without cameras. Red light camera enforcement programs were associated with a statistically significant reduction in the citywide rate of fatal red light running crashes and a smaller but still significant reduction in the rate of all fatal crashes at signalized intersections. The study adds to the large body of evidence that red light camera enforcement can prevent the most serious crashes. Communities seeking to reduce crashes at intersections should consider this evidence. Copyright © 2011 Elsevier Ltd. All rights reserved.

Nanowebs and nanocables of silicon carbide

NASA Astrophysics Data System (ADS)

Shim, Hyun Woo; Huang, Hanchen

2007-08-01

This paper presents two novel hierarchical structures of SiC-SiO2 core-shell nanowires: (a) nanocables in the form of multi-core and single shell and (b) nanowebs in the form of intersecting nanowires and nanocables, augmented by variable amounts of SiO2 membranes. The two structures are controllable through variations of substrate temperature and source chemistry. The hierarchical nanostructures, together with the controllability, may offer superb mechanical properties in composite applications. Finally, the authors propose a model of nanowebs and nanocables formation, as a result of nanowires intersection and alignment.

Effects of major-road vehicle speed and driver age and gender on left-turn gap acceptance.

PubMed

Yan, Xuedong; Radwan, Essam; Guo, Dahai

2007-07-01

Because the driver's gap-acceptance maneuver is a complex and risky driving behavior, it is a highly concerned topic for traffic safety and operation. Previous studies have mainly focused on the driver's gap acceptance decision itself but did not pay attention to the maneuver process and driving behaviors. Using a driving simulator experiment for left-turn gap acceptance at a stop-controlled intersection, this study evaluated the effects of major traffic speed and driver age and gender on gap acceptance behaviors. The experiment results illustrate relationships among drivers' left-turn gap decision, driver's acceleration rate, steering action, and the influence of the gap-acceptance maneuver on the vehicles in the major traffic stream. The experiment results identified an association between high crash risk and high traffic speed at stop-controlled intersections. The older drivers, especially older female drivers, displayed a conservative driving attitude as a compensation for reduced driving ability, but also showed to be the most vulnerable group for the relatively complex driving maneuvers.

Aging road user studies of intersection safety : lab and simulator-based studies of crosswalk markings and flashing yellow arrow comprehension -- phase 2 : [summary].

DOT National Transportation Integrated Search

2014-10-01

Nearly half of all traffic-related fatalities occur : at intersections, so engineering intersections : for greater safety remains a priority for the : Florida Department of Transportation (FDOT). : Engineering in this case must take into accoun...

Application of Foldcore Sandwich Structures in Helicopter Subfloor Energy Absorption Structure

NASA Astrophysics Data System (ADS)

Zhou, H. Z.; Wang, Z. J.

2017-10-01

The intersection element is an important part of the helicopter subfloor structure. The numerical simulation model of the intersection element is established and the crush simulation is conducted. The simulation results agree well with the experiment results. In order to improve the buffering capacity and energy-absorbing capacity, the intersection element is redesigned. The skin and the floor in the intersection element are replaced with foldcore sandwich structures. The new intersection element is studied using the same simulation method as the typical intersection element. The analysis result shows that foldcore can improve the buffering capacity and the energy-absorbing capacity, and reduce the structure mass.

Low Emissions and Delay Optimization for an Isolated Signalized Intersection Based on Vehicular Trajectories

PubMed Central

2015-01-01

A traditional traffic signal control system is established based on vehicular delay, queue length, saturation and other indicators. However, due to the increasing severity of urban environmental pollution issues and the development of a resource-saving and environmentally friendly social philosophy, the development of low-carbon and energy-efficient urban transport is required. This paper first defines vehicular trajectories and the calculation of vehicular emissions based on VSP. Next, a regression analysis method is used to quantify the relationship between vehicular emissions and delay, and a traffic signal control model is established to reduce emissions and delay using the enumeration method combined with saturation constraints. Finally, one typical intersection of Changchun is selected to verify the model proposed in this paper; its performance efficiency is also compared using simulations in VISSIM. The results of this study show that the proposed model can significantly reduce vehicle delay and traffic emissions simultaneously. PMID:26720095

Low Emissions and Delay Optimization for an Isolated Signalized Intersection Based on Vehicular Trajectories.

PubMed

Lin, Ciyun; Gong, Bowen; Qu, Xin

2015-01-01

A traditional traffic signal control system is established based on vehicular delay, queue length, saturation and other indicators. However, due to the increasing severity of urban environmental pollution issues and the development of a resource-saving and environmentally friendly social philosophy, the development of low-carbon and energy-efficient urban transport is required. This paper first defines vehicular trajectories and the calculation of vehicular emissions based on VSP. Next, a regression analysis method is used to quantify the relationship between vehicular emissions and delay, and a traffic signal control model is established to reduce emissions and delay using the enumeration method combined with saturation constraints. Finally, one typical intersection of Changchun is selected to verify the model proposed in this paper; its performance efficiency is also compared using simulations in VISSIM. The results of this study show that the proposed model can significantly reduce vehicle delay and traffic emissions simultaneously.

Complex Road Intersection Modelling Based on Low-Frequency GPS Track Data

NASA Astrophysics Data System (ADS)

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.

The problem with the phrase women and minorities: intersectionality-an important theoretical framework for public health.

PubMed

Bowleg, Lisa

2012-07-01

Intersectionality is a theoretical framework that posits that multiple social categories (e.g., race, ethnicity, gender, sexual orientation, socioeconomic status) intersect at the micro level of individual experience to reflect multiple interlocking systems of privilege and oppression at the macro, social-structural level (e.g., racism, sexism, heterosexism). Public health's commitment to social justice makes it a natural fit with intersectionality's focus on multiple historically oppressed populations. Yet despite a plethora of research focused on these populations, public health studies that reflect intersectionality in their theoretical frameworks, designs, analyses, or interpretations are rare. Accordingly, I describe the history and central tenets of intersectionality, address some theoretical and methodological challenges, and highlight the benefits of intersectionality for public health theory, research, and policy.

Conditions that influence drivers' yielding behavior at uncontrolled crossings and intersections with traffic signal controls.

DOT National Transportation Integrated Search

2015-08-31

There is a dearth of studies on how pedestrian who are blind might positively influence driver yielding in different travel situations. This project assessed common pedestrian behaviors (head turning, holding a cane, taking a step, holding up a hand,...

Development of safety performance functions and other decision support tools to assess pedestrian and bicycle safety : final report.

DOT National Transportation Integrated Search

2016-09-30

field study was performed at 40 uncontrolled midblock crosswalks and 26 signalized intersections on low-speed roadways selected from the areas surrounding three major urban college campuses across lower Michigan. An array of existing traffic control ...

National occupant protection use survey 1996 : controlled intersection study

DOT National Transportation Integrated Search

1997-08-01

In 1996, the overall observed shoulder belt use rate was 61.5%, as measured by the National Occupant Protection Use Survey (NOPUS). This is compared to 58.0% observed in 1994. The NOPUS was conducted in the Fall of 1996 to estimate safety belt use in...

Study of the effects of wind power and vortex-induced vibrations to establish fatigue design criteria for high-mast poles.

DOT National Transportation Integrated Search

2011-08-01

Traffic signal and high-mast poles are used by transportation agencies to control and illuminate intersections; their structural design is governed by national specifications. High-mast poles are luminaire supports located near highway interchanges t...

Review of Airport Ground Traffic Models Including an Evaluation of the ASTS Computer Program

DOT National Transportation Integrated Search

1972-12-01

The report covers an evaluation of Airport Ground Traffic models for the purpose of simulating an Autonomous Local Intersection Controller. All known models were reviewed and a detailed study was performed on the two in-house models the ASTS and ROSS...

Older driver failures of attention at intersections: using change blindness methods to assess turn decision accuracy.

PubMed

Caird, Jeff K; Edwards, Christopher J; Creaser, Janet I; Horrey, William J

2005-01-01

A modified version of the flicker technique to induce change blindness was used to examine the effects of time constraints on decision-making accuracy at intersections on a total of 62 young (18-25 years), middle-aged (26-64 years), young-old (65-73 years), and old-old (74+ years) drivers. Thirty-six intersection photographs were manipulated so that one object (i.e., pedestrian, vehicle, sign, or traffic control device) in the scene would change when the images were alternated for either 5 or 8 s using the modified flicker method. Young and middle-aged drivers made significantly more correct decisions than did young-old and old-old drivers. Logistic regression analysis of the data indicated that age and/or time were significant predictors of decision performance in 14 of the 36 intersections. Actual or potential applications of this research include driving assessment and crash investigation.

Assessment of statewide intersection safety performance.

DOT National Transportation Integrated Search

2011-06-01

This report summarizes the results of an analysis of the safety performance of Oregons intersections. Following a pilot : study, a database of 500 intersections randomly sampled from around the state of Oregon in both urban and rural : environment...

Understanding How Race/Ethnicity and Gender Define Age-Trajectories of Disability: An Intersectionality Approach

PubMed Central

Warner, David F.; Brown, Tyson H.

2011-01-01

A number of studies have demonstrated wide disparities in health among racial/ethnic groups and by gender, yet few have examined how race/ethnicity and gender intersect or combine to affect the health of older adults. The tendency of prior research to treat race/ethnicity and gender separately has potentially obscured important differences in how health is produced and maintained, undermining efforts to eliminate health disparities. The current study extends previous research by taking an intersectionality approach (Mullings & Schulz, 2006), grounded in life course theory, conceptualizing and modeling trajectories of functional limitations as dynamic life course processes that are jointly and simultaneously defined by race/ethnicity and gender. Data from the nationally representative 1994–2006 US Health and Retirement Study and growth curve models are utilized to examine racial/ethnic/gender differences in intra-individual change in functional limitations among White, Black and Mexican American Men and Women, and the extent to which differences in life course capital account for group disparities in initial health status and rates of change with age. Results support an intersectionality approach, with all demographic groups exhibiting worse functional limitation trajectories than White Men. Whereas White Men had the lowest disability levels at baseline, White Women and racial/ethnic minority Men had intermediate disability levels and Black and Hispanic Women had the highest disability levels. These health disparities remained stable with age—except among Black Women who experience a trajectory of accelerated disablement. Dissimilar early life social origins, adult socioeconomic status, marital status, and health behaviors explain the racial/ethnic disparities in functional limitations among Men but only partially explain the disparities among Women. Net of controls for life course capital, Women of all racial/ethnic groups have higher levels of functional limitations relative to White Men and Men of the same race/ethnicity. Findings highlight the utility of an intersectionality approach to understanding health disparities. PMID:21470737

Understanding how race/ethnicity and gender define age-trajectories of disability: an intersectionality approach.

PubMed

Warner, David F; Brown, Tyson H

2011-04-01

A number of studies have demonstrated wide disparities in health among racial/ethnic groups and by gender, yet few have examined how race/ethnicity and gender intersect or combine to affect the health of older adults. The tendency of prior research to treat race/ethnicity and gender separately has potentially obscured important differences in how health is produced and maintained, undermining efforts to eliminate health disparities. The current study extends previous research by taking an intersectionality approach (Mullings & Schulz, 2006), grounded in life course theory, conceptualizing and modeling trajectories of functional limitations as dynamic life course processes that are jointly and simultaneously defined by race/ethnicity and gender. Data from the nationally representative 1994-2006 US Health and Retirement Study and growth curve models are utilized to examine racial/ethnic/gender differences in intra-individual change in functional limitations among White, Black and Mexican American Men and Women, and the extent to which differences in life course capital account for group disparities in initial health status and rates of change with age. Results support an intersectionality approach, with all demographic groups exhibiting worse functional limitation trajectories than White Men. Whereas White Men had the lowest disability levels at baseline, White Women and racial/ethnic minority Men had intermediate disability levels and Black and Hispanic Women had the highest disability levels. These health disparities remained stable with age-except among Black Women who experience a trajectory of accelerated disablement. Dissimilar early life social origins, adult socioeconomic status, marital status, and health behaviors explain the racial/ethnic disparities in functional limitations among Men but only partially explain the disparities among Women. Net of controls for life course capital, Women of all racial/ethnic groups have higher levels of functional limitations relative to White Men and Men of the same race/ethnicity. Findings highlight the utility of an intersectionality approach to understanding health disparities. Copyright © 2011 Elsevier Ltd. All rights reserved.

At the cross-roads: an on-road examination of driving errors at intersections.

PubMed

Young, Kristie L; Salmon, Paul M; Lenné, Michael G

2013-09-01

A significant proportion of road trauma occurs at intersections. Understanding the nature of driving errors at intersections therefore has the potential to lead to significant injury reductions. To further understand how the complexity of modern intersections shapes behaviour of these errors are compared to errors made mid-block, and the role of wider systems failures in intersection error causation is investigated in an on-road study. Twenty-five participants drove a pre-determined urban route incorporating 25 intersections. Two in-vehicle observers recorded the errors made while a range of other data was collected, including driver verbal protocols, video, driver eye glance behaviour and vehicle data (e.g., speed, braking and lane position). Participants also completed a post-trial cognitive task analysis interview. Participants were found to make 39 specific error types, with speeding violations the most common. Participants made significantly more errors at intersections compared to mid-block, with misjudgement, action and perceptual/observation errors more commonly observed at intersections. Traffic signal configuration was found to play a key role in intersection error causation, with drivers making more errors at partially signalised compared to fully signalised intersections. Copyright © 2012 Elsevier Ltd. All rights reserved.

Neighborhood design and rates of walking and biking to elementary school in 34 California communities.

PubMed

Braza, Mark; Shoemaker, Wendy; Seeley, Anne

2004-01-01

This study evaluates the relationship between neighborhood design and rates of students walking and biking to elementary school. Pairwise correlations and multiple regression models were estimated based on a cross-sectional study of elementary schools and their surrounding neighborhoods. Setting and Subjects. Thirty-four (23%) of 150 California public elementary schools holding October 1999 Walk to School Day events participated in the study. Teachers asked fifth-grade students how they arrived to school 1 week before Walk to School Day. 1990 U.S. Census data measured population density and number of intersections per street mile, whereas 1998-1999 California Department of Education data measured school size, the percentage of students receiving public welfare, and the percentage of students of various ethnicities. Population density (p = .000) and school size (p = .053) were significantly associated with walking and biking rates in regression models controlling for number of intersections per street mile, the percentage of students receiving public welfare, and the percentage of students of various ethnicities. The number of intersections per street mile was associated with walking and biking rates in pairwise correlations (p = .003) but not in regression models. The results support the hypothesis that the walking and biking rates are higher in denser neighborhoods and to smaller schools but do not support the hypothesis that rates are higher in neighborhoods with a high number of intersections per street mile. We suggest that detailed data for a larger sample of students would allow statistical models to isolate the effect of specific design characteristics.

Understanding the Influence of Race/Ethnicity, Gender, and Class on Inequalities in Academic and Non-Academic Outcomes among Eighth-Grade Students: Findings from an Intersectionality Approach.

PubMed

Bécares, Laia; Priest, Naomi

2015-01-01

Socioeconomic, racial/ethnic, and gender inequalities in academic achievement have been widely reported in the US, but how these three axes of inequality intersect to determine academic and non-academic outcomes among school-aged children is not well understood. Using data from the US Early Childhood Longitudinal Study-Kindergarten (ECLS-K; N = 10,115), we apply an intersectionality approach to examine inequalities across eighth-grade outcomes at the intersection of six racial/ethnic and gender groups (Latino girls and boys, Black girls and boys, and White girls and boys) and four classes of socioeconomic advantage/disadvantage. Results of mixture models show large inequalities in socioemotional outcomes (internalizing behavior, locus of control, and self-concept) across classes of advantage/disadvantage. Within classes of advantage/disadvantage, racial/ethnic and gender inequalities are predominantly found in the most advantaged class, where Black boys and girls, and Latina girls, underperform White boys in academic assessments, but not in socioemotional outcomes. In these latter outcomes, Black boys and girls perform better than White boys. Latino boys show small differences as compared to White boys, mainly in science assessments. The contrasting outcomes between racial/ethnic and gender minorities in self-assessment and socioemotional outcomes, as compared to standardized assessments, highlight the detrimental effect that intersecting racial/ethnic and gender discrimination have in patterning academic outcomes that predict success in adult life. Interventions to eliminate achievement gaps cannot fully succeed as long as social stratification caused by gender and racial discrimination is not addressed.

Development of a framework for evaluating yellow timing at signalized intersections.

DOT National Transportation Integrated Search

2011-02-01

Studies show that the proper design of clearance intervals has significant implications for intersection safety. For : example, in 2001, approximately 218,000 red-light-running crashes occurred at signalized intersections in the United States. : Thes...

Music Teacher Knowledge: An Examination of the Intersections between Instrumental Music Teaching and Conducting

ERIC Educational Resources Information Center

Forrester, Sommer H.

2018-01-01

The purpose of this study was to examine the complexities of instrumental music teacher knowledge as they relate to the intersection between instrumental music teaching and conducting, and to explore how participants describe and perceive these intersections. The key research question guiding this study was, How do high school instrumental music…

Investigating the Intersection of Poverty and Race in Gifted Education Journals: A 15-Year Analysis

ERIC Educational Resources Information Center

Goings, Ramon B.; Ford, Donna Y.

2018-01-01

Using a two-phase content analysis approach, this study examined how education scholars have discussed the intersection of giftedness, race, and poverty in gifted academic journals from 2000 to 2015. Specifically, the authors explored the following questions: (a) What are the characteristics of studies published that explore the intersection of…

Imputation across genotyping arrays for genome-wide association studies: assessment of bias and a correction strategy.

PubMed

Johnson, Eric O; Hancock, Dana B; Levy, Joshua L; Gaddis, Nathan C; Saccone, Nancy L; Bierut, Laura J; Page, Grier P

2013-05-01

A great promise of publicly sharing genome-wide association data is the potential to create composite sets of controls. However, studies often use different genotyping arrays, and imputation to a common set of SNPs has shown substantial bias: a problem which has no broadly applicable solution. Based on the idea that using differing genotyped SNP sets as inputs creates differential imputation errors and thus bias in the composite set of controls, we examined the degree to which each of the following occurs: (1) imputation based on the union of genotyped SNPs (i.e., SNPs available on one or more arrays) results in bias, as evidenced by spurious associations (type 1 error) between imputed genotypes and arbitrarily assigned case/control status; (2) imputation based on the intersection of genotyped SNPs (i.e., SNPs available on all arrays) does not evidence such bias; and (3) imputation quality varies by the size of the intersection of genotyped SNP sets. Imputations were conducted in European Americans and African Americans with reference to HapMap phase II and III data. Imputation based on the union of genotyped SNPs across the Illumina 1M and 550v3 arrays showed spurious associations for 0.2 % of SNPs: ~2,000 false positives per million SNPs imputed. Biases remained problematic for very similar arrays (550v1 vs. 550v3) and were substantial for dissimilar arrays (Illumina 1M vs. Affymetrix 6.0). In all instances, imputing based on the intersection of genotyped SNPs (as few as 30 % of the total SNPs genotyped) eliminated such bias while still achieving good imputation quality.

Modeling traffic accidents at signalized intersections in the city of Norfolk, VA.

DOT National Transportation Integrated Search

2010-12-31

This study was an attempt to apply a proactive approach using traffic pattern and signalized intersection characteristics to predict accident rates at signalized intersections in a citys arterial network. An earlier analysis of accident data at se...

An ex post facto evaluation framework for place-based police interventions.

PubMed

Braga, Anthony A; Hureau, David M; Papachristos, Andrew V

2011-12-01

A small but growing body of research evidence suggests that place-based police interventions generate significant crime control gains. While place-based policing strategies have been adopted by a majority of U.S. police departments, very few agencies make a priori commitments to rigorous evaluations. Recent methodological developments were applied to conduct a rigorous ex post facto evaluation of the Boston Police Department's Safe Street Team (SST) hot spots policing program. A nonrandomized quasi-experimental design was used to evaluate the violent crime control benefits of the SST program at treated street segments and intersections relative to untreated street segments and intersections. Propensity score matching techniques were used to identify comparison places in Boston. Growth curve regression models were used to analyze violent crime trends at treatment places relative to control places. UNITS OF ANALYSIS: Using computerized mapping and database software, a micro-level place database of violent index crimes at all street segments and intersections in Boston was created. Yearly counts of violent index crimes between 2000 and 2009 at the treatment and comparison street segments and intersections served as the key outcome measure. The SST program was associated with a statistically significant reduction in violent index crimes at the treatment places relative to the comparison places without displacing crime into proximate areas. To overcome the challenges of evaluation in real-world settings, evaluators need to continuously develop innovative approaches that take advantage of new theoretical and methodological approaches.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Yue J.; Malikopoulos, Andreas; Cassandras, Christos G.

We address the problem of coordinating online a continuous flow of connected and automated vehicles (CAVs) crossing two adjacent intersections in an urban area. We present a decentralized optimal control framework whose solution yields for each vehicle the optimal acceleration/deceleration at any time in the sense of minimizing fuel consumption. The solu- tion, when it exists, allows the vehicles to cross the intersections without the use of traffic lights, without creating congestion on the connecting road, and under the hard safety constraint of collision avoidance. The effectiveness of the proposed solution is validated through simulation considering two intersections located inmore » downtown Boston, and it is shown that coordination of CAVs can reduce significantly both fuel consumption and travel time.« less

Lighting levels for isolated intersections : leading to safety improvements : final report.

DOT National Transportation Integrated Search

2015-01-01

A number of studies have linked the benefits of roadway lighting to a reduction in crash rates at night for a variety : of roadway types including rural intersections. Assessing the effectiveness of intersection lighting has primarily : relied upon c...

Real-time bicycle detection at signalized intersections using thermal imaging technology

NASA Astrophysics Data System (ADS)

Collaert, Robin

2013-02-01

More and more governments and authorities around the world are promoting the use of bicycles in cities, as this is healthy for the bicyclist and improves the quality of life in general. Safety and efficiency of bicyclists has become a major focus. To achieve this, there is a need for a smarter approach towards the control of signalized intersections. Various traditional detection technologies, such as video, microwave radar and electromagnetic loops, can be used to detect vehicles at signalized intersections, but none of these can consistently separate bikes from other traffic, day and night and in various weather conditions. As bikes should get a higher priority and also require longer green time to safely cross the signalized intersection, traffic managers are looking for alternative detection systems that can make the distinction between bicycles and other vehicles near the stop bar. In this paper, the drawbacks of a video-based approach are presented, next to the benefits of a thermal-video-based approach for vehicle presence detection with separation of bicycles. Also, the specific technical challenges are highlighted in developing a system that combines thermal image capturing, image processing and output triggering to the traffic light controller in near real-time and in a single housing.

A speed guidance strategy for multiple signalized intersections based on car-following model

NASA Astrophysics Data System (ADS)

Tang, Tie-Qiao; Yi, Zhi-Yan; Zhang, Jian; Wang, Tao; Leng, Jun-Qiang

2018-04-01

Signalized intersection has great roles in urban traffic system. The signal infrastructure and the driving behavior near the intersection are paramount factors that have significant impacts on traffic flow and energy consumption. In this paper, a speed guidance strategy is introduced into a car-following model to study the driving behavior and the fuel consumption in a single-lane road with multiple signalized intersections. The numerical results indicate that the proposed model can reduce the fuel consumption and the average stop times. The findings provide insightful guidance for the eco-driving strategies near the signalized intersections.

Field Effect Flow Control in a Polymer T-Intersection Microfluidic Network

NASA Technical Reports Server (NTRS)

Sniadecki, Nathan J.; Chang, Richard; Beamesderfer, Mike; Lee, Cheng S.; DeVoe, Don L.

2003-01-01

We present a study of induced pressure pumping in a polymer microchannel due to differential electroosmotic flow @OF) rates via field-effect flow control (FEFC). The experimental results demonstrate that the induced pressure pumping is dependent on the distance of the FEFC gate from the cathodic gate. A proposed flow model based on a linearly-decaying zeta potential profile is found to successfully predict experimental trends.

Optical-bistability-enabled control of resonant light transmission for an atom-cavity system

NASA Astrophysics Data System (ADS)

Sawant, Rahul; Rangwala, S. A.

2016-02-01

The control of light transmission through a standing-wave Fabry-Pérot cavity containing atoms is theoretically and numerically investigated, when the cavity mode beam and an intersecting control beam are both close to specific atomic resonances. A four-level atomic system is considered and its interaction with the cavity mode is studied by solving for the cavity field and atomic state populations. The conditions for optical bistability of the atom-cavity system are obtained. The response of the intracavity intensity to an intersecting beam on atomic resonance is understood in the presence of stationary atoms (closed system) and nonstatic atoms (open system) in the cavity. The nonstatic system of atoms is modelled by adjusting the atomic state populations to represent the exchange of atoms in the cavity mode, which corresponds to a thermal environment where atoms are moving in and out of the cavity mode volume. The control behavior with three- and two-level atomic systems is also studied, and the rich physics arising out of these systems for closed and open atomic systems is discussed. The solutions to the models are used to interpret the steady-state and transient behavior observed by Sharma et al. [Phys. Rev. A 91, 043824 (2015)], 10.1103/PhysRevA.91.043824.

The trend of road traffic crashes at urban signalised intersection

NASA Astrophysics Data System (ADS)

Farhana Nasarrudin, Nurul; Razelan, Intan Suhana Mohd

2018-04-01

Road traffic crash is one of the main contributing factors for deaths in the world. Intersection is listed as the second road type which road crashes occurred frequently. Hence, the traffic light was installed to minimise the road crashes at intersection. However, the crashes are still occurring and arising. The objective of this study was to exhibit the trend of road crashes at the signalised intersections. The data of road crashes for the past 6 years were analysed using descriptive analysis. The results showed that the road traffic crashes at three- and four-legged signalised intersection recorded the increasing trend. In conclusion, this finding shows that the road traffic crashes for these types of signalised intersection in Malaysia is rising. It is also one the contributors to the increasing number of crashes in Malaysia. This finding will encourage the local authority to conduct awareness programs on the safety at the signalised intersection.

Incorporating intersectionality theory into population health research methodology: challenges and the potential to advance health equity.

PubMed

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 of intersectionality can promote the creation of evidence that is directly useful in population-level interventions such as policy changes, or that is specific enough to be applicable within the social contexts of affected communities. Copyright © 2014 The Author. Published by Elsevier Ltd.. All rights reserved.

Integrating intersectionality and biomedicine in health disparities research.

PubMed

Kelly, Ursula A

2009-01-01

Persisting health disparities have lead to calls for an increase in health research to address them. Biomedical scientists call for research that stratifies individual indicators associated with health disparities, for example, ethnicity. Feminist social scientists recommend feminist intersectionality research. Intersectionality is the multiplicative effect of inequalities experienced by nondominant marginalized groups, for example, ethnic minorities, women, and the poor. The elimination of health disparities necessitates integration of both paradigms in health research. This study provides a practical application of the integration of biomedical and feminist intersectionality paradigms in nursing research, using a psychiatric intervention study with battered Latino women as an example.

Evaluating the Impacts of Red Light Camera Deployment on Intersection Traffic Safety

DOT National Transportation Integrated Search

2018-06-01

Red-light cameras (RLC) are a popular countermeasure to reduce red-light running and improve intersection safety. Studies show that the reduction in side impact crashes at RLC intersections are often accompanied by no-change or an increase in the num...

Intersection negotiation problems of older drivers. Volume 2, Background synthesis on age and intersection driving difficulties

DOT National Transportation Integrated Search

1998-09-01

This project included a background literature synthesis and observational field study. The research goals were to document driving problems and errors at intersections, for older drivers using their own cars to travel familiar and unfamiliar routes, ...

A Heckman selection model for the safety analysis of signalized intersections

PubMed Central

Wong, S. C.; Zhu, Feng; Pei, Xin; Huang, Helai; Liu, Youjun

2017-01-01

Purpose The objective of this paper is to provide a new method for estimating crash rate and severity simultaneously. Methods This study explores a Heckman selection model of the crash rate and severity simultaneously at different levels and a two-step procedure is used to investigate the crash rate and severity levels. The first step uses a probit regression model to determine the sample selection process, and the second step develops a multiple regression model to simultaneously evaluate the crash rate and severity for slight injury/kill or serious injury (KSI), respectively. The model uses 555 observations from 262 signalized intersections in the Hong Kong metropolitan area, integrated with information on the traffic flow, geometric road design, road environment, traffic control and any crashes that occurred during two years. Results The results of the proposed two-step Heckman selection model illustrate the necessity of different crash rates for different crash severity levels. Conclusions A comparison with the existing approaches suggests that the Heckman selection model offers an efficient and convenient alternative method for evaluating the safety performance at signalized intersections. PMID:28732050

Exploratory multinomial logit model-based driver injury severity analyses for teenage and adult drivers in intersection-related crashes.

PubMed

Wu, Qiong; Zhang, Guohui; Ci, Yusheng; Wu, Lina; Tarefder, Rafiqul A; Alcántara, Adélamar Dely

2016-05-18

Teenage drivers are more likely to be involved in severely incapacitating and fatal crashes compared to adult drivers. Moreover, because two thirds of urban vehicle miles traveled are on signal-controlled roadways, significant research efforts are needed to investigate intersection-related teenage driver injury severities and their contributing factors in terms of driver behavior, vehicle-infrastructure interactions, environmental characteristics, roadway geometric features, and traffic compositions. Therefore, this study aims to explore the characteristic differences between teenage and adult drivers in intersection-related crashes, identify the significant contributing attributes, and analyze their impacts on driver injury severities. Using crash data collected in New Mexico from 2010 to 2011, 2 multinomial logit regression models were developed to analyze injury severities for teenage and adult drivers, respectively. Elasticity analyses and transferability tests were conducted to better understand the quantitative impacts of these factors and the teenage driver injury severity model's generality. The results showed that although many of the same contributing factors were found to be significant in the both teenage and adult driver models, certain different attributes must be distinguished to specifically develop effective safety solutions for the 2 driver groups. The research findings are helpful to better understand teenage crash uniqueness and develop cost-effective solutions to reduce intersection-related teenage injury severities and facilitate driver injury mitigation research.

Digital signal processing and control and estimation theory -- Points of tangency, area of intersection, and parallel directions

NASA Technical Reports Server (NTRS)

Willsky, A. S.

1976-01-01

A number of current research directions in the fields of digital signal processing and modern control and estimation theory were studied. Topics such as stability theory, linear prediction and parameter identification, system analysis and implementation, two-dimensional filtering, decentralized control and estimation, image processing, and nonlinear system theory were examined in order to uncover some of the basic similarities and differences in the goals, techniques, and philosophy of the two disciplines. An extensive bibliography is included.

Gendered racism and the sexual and reproductive health of Black and Latina Women.

PubMed

Rosenthal, Lisa; Lobel, Marci

2018-02-15

To understand health disparities, it is important to use an intersectional framework that examines unique experiences of oppression faced by particular groups due to their intersecting identities and social positions linked to societal structures. We focus on Black and Latina women and their experiences with 'gendered racism' - unique forms of oppression due to the intersection of race/ethnicity and gender - to foster understanding of disparities between Black and Latina versus White women in sexual and reproductive health outcomes in the U.S. Specifically, we focus on stereotype-related gendered racism (ongoing discrimination and stereotype threat based on historically-rooted stereotypes about Black and Latina women's sexuality and motherhood) and birth control-related mistrust (ongoing mistrust of the government and medical system related to birth control due to historical and current abuses). We analyzed data from two survey studies with adult women in New York (Study 1: paper-and-pencil community data collection, N = 135, M age  = 43.35) and across the U.S. (Study 2: online data collection, N = 343, M age  = 29.49) who were currently pregnant or had at least one child and identified as Black, Latina, or White. Black and Latina women reported greater frequency of and concern over stereotype-related gendered racism (F(3,131) = 17.90, p < .001 Study 1; F(3,339) = 22.23, p < .001 Study 2) and greater birth control-related mistrust (F(3,131) = 7.55, p < .001 Study 1; F(3,339) = 17.32, p < .001 Study 2) than White women did. In turn, stereotype-related gendered racism was positively associated with pregnancy-specific stress (ß = .40, p < .001 Study 1; ß = .33, p < .001 Study 2), and birth control-related mistrust was negatively associated with sexual relationship power (ß = -.19, p = .002 Study 2), which are factors known to contribute to birth outcomes and sexual risk, respectively. Findings suggest that gendered racism may play an important role in existing racial/ethnic disparities in women's sexual and reproductive health outcomes, and interventions addressing gendered racism at multiple levels are needed to promote health equity.

The Intersections of Living-Learning Programs and Social Identity as Factors of Academic Achievement and Intellectual Engagement

ERIC Educational Resources Information Center

Pasque, Penny A.; Murphy, Rena

2005-01-01

Findings from this study show that living-learning (LL) programs at a research institution in the Midwest have a series of positive outcomes for both academic achievement and intellectual engagement. Controlling for past academic achievement, socioeconomic status, and demographic characteristics, LL programs are predictors, albeit small…

Intertwined Effects of Gender and Migration Status on Persistence in SET Study Programmes

ERIC Educational Resources Information Center

Guenther, Elisabeth Anna; Koeszegi, Sabine Theresia

2017-01-01

This paper explores the intersectional interference of gender and migration status on students' persistence at an Austrian University of Technology. While controlling for the pre-university education and performance indicators, we estimate the odds for the persistence of male and female students, as well as of students with diverse migration…

Behavioral Markers of Emergent Stranger Anxiety in Infants and Toddlers with Fragile X Syndrome

ERIC Educational Resources Information Center

Tonnsen, Bridgette; Scherr, Jessica; Reisinger, Debra; Roberts, Jane

2017-01-01

Studying anxiety in neurogenetic syndromes may inform the intersection of biological and developmental risks, facilitating effective and targeted interventions. We longitudinally examined stranger fear in infants and toddlers with fragile X syndrome (FXS; n = 46) and typical controls (n = 33), as well as associations between observed stranger fear…

A computer program to generate two-dimensional grids about airfoils and other shapes by the use of Poisson's equation

NASA Technical Reports Server (NTRS)

Sorenson, R. L.

1980-01-01

A method for generating two dimensional finite difference grids about airfoils and other shapes by the use of the Poisson differential equation is developed. The inhomogeneous terms are automatically chosen such that two important effects are imposed on the grid at both the inner and outer boundaries. The first effect is control of the spacing between mesh points along mesh lines intersecting the boundaries. The second effect is control of the angles with which mesh lines intersect the boundaries. A FORTRAN computer program has been written to use this method. A description of the program, a discussion of the control parameters, and a set of sample cases are included.

Traffic control at crossroad that cut railroad based on friendly environment: Case : Crossroads at Prof. M. Yamin road with Gaharu road in Medan

NASA Astrophysics Data System (ADS)

Hutauruk, Sindak

2017-09-01

The frequent congestion causes accumulation of vehicles at the intersection of roads cutting off railroads, reducing the functionality of highway services, the loss of vehicle functions as a means of transportation, waste of fuel energy, and CO2 increase in intersections. The occurrence of congestion caused by the absence of integration of traffic light controls by opening and closing the railway barrier, therefore need to be done integrated control especially during and after a while train crossing the highway. The case raised in this study is the crossroads Prof. H.M. Jalan Yamin with Gaharu road in Medan. Researchers tried to solve the problem by designing and creating a tool that would coordinate and regulate traffic lights with railroad doors, thus reducing congestion for 23 minutes, reducing fuel by as much as 60,340 liters per day, thereby reducing CO2 exhaust gases in the area. This tool uses microcontroller as its control center. This design is done with a miniature simulation, meaning it is not done in the actual situation, but the field conditions can be represented in the simulation in the form of miniature.

The Effect of Gender and Race Intersectionality on Student Learning Outcomes in Engineering

ERIC Educational Resources Information Center

Ro, Hyun Kyoung; Loya, Karla I.

2015-01-01

Women and underrepresented minorities in traditionally White and male-dominated disciplines tend to report lower learning outcomes than their White peers. Adopting a feminist intersectionality framework, this study looks at the intersections of gender and race to investigate differences in self-assessed learning outcomes in engineering…

Shifting Identities: Negotiating Intersections of Race and Gender in Canadian Administrative Contexts

ERIC Educational Resources Information Center

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…

State of the art studies/FY87 : task 5 - increasing intersection capacity with additional through lanes

DOT National Transportation Integrated Search

1987-10-01

A review of the literature and a state-of-the-practice survey were conducted of procedures relating to the addition of through lanes at intersections. The capacity and level of service change at the intersection is of interest, since the reduction in...

Intersectionality research in counseling psychology.

PubMed

Grzanka, Patrick R; Santos, Carlos E; Moradi, Bonnie

2017-10-01

This article introduces the special section on intersectionality research in counseling psychology. Across the 4 manuscripts that constitute this special section, a clear theme emerges: a need to return to the roots and politics of intersectionality. Importantly, the 2 empirical articles in this special section (Jerald, Cole, Ward, & Avery, 2017; Lewis, Williams, Peppers, & Gadson, 2017) are studies of Black women's experiences: a return, so to speak, to the subject positions and social locations from which intersectionality emanates. Shin et al. (2017) explore why this focus on Black feminist thought and social justice is so important by highlighting the persistent weaknesses in how much research published in leading counseling psychology journals has tended to use intersectionality as a way to talk about multiple identities, rather than as a framework for critiquing systemic, intersecting forms of oppression and privilege. Shin and colleagues also point to the possibilities intersectionality affords us when scholars realize the transformative potential of this critical framework. Answers to this call for transformative practices are foregrounded in Moradi and Grzanka's (2017) contribution, which surveys the interdisciplinary literature on intersectionality and presents a series of guidelines for using intersectionality responsibly. We close with a discussion of issues concerning the applications of intersectionality to counseling psychology research that spans beyond the contributions of each manuscript in this special section. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Cooperative crossing of traffic intersections in a distributed robot system

NASA Astrophysics Data System (ADS)

Rausch, Alexander; Oswald, Norbert; Levi, Paul

1995-09-01

In traffic scenarios a distributed robot system has to cope with problems like resource sharing, distributed planning, distributed job scheduling, etc. While travelling along a street segment can be done autonomously by each robot, crossing of an intersection as a shared resource forces the robot to coordinate its actions with those of other robots e.g. by means of negotiations. We discuss the issue of cooperation on the design of a robot control architecture. Task and sensor specific cooperation between robots requires the robots' architectures to be interlinked at different hierarchical levels. Inside each level control cycles are running in parallel and provide fast reaction on events. Internal cooperation may occur between cycles of the same level. Altogether the architecture is matrix-shaped and contains abstract control cycles with a certain degree of autonomy. Based upon the internal structure of a cycle we consider the horizontal and vertical interconnection of cycles to form an individual architecture. Thereafter we examine the linkage of several agents and its influence on an interacting architecture. A prototypical implementation of a scenario, which combines aspects of active vision and cooperation, illustrates our approach. Two vision-guided vehicles are faced with line following, intersection recognition and negotiation.

Using intersectionality responsibly: Toward critical epistemology, structural analysis, and social justice activism.

PubMed

Moradi, Bonnie; Grzanka, Patrick R

2017-10-01

The increasing popularity of the concept of intersectionality in the social sciences, including in psychology, represents an opportunity to reflect on the state of stewardship of this concept, its roots, and its promise. In this context, the authors aim to promote responsible stewardship of intersectionality and to tip the momentum of intersectionality's flourishing toward fuller use and engagement of its roots and promise for understanding and challenging dynamics of power, privilege, and oppression. To this end, this article provides a set of guidelines for reflection and action. The authors organize these guidelines along 3 major formulations of intersectionality: intersectionality as a field of study, as analytic strategy or disposition, and as critical praxis for social justice. Ultimately, the authors call for expanding the use of intersectionality toward fuller engagement with its roots in Black feminist thought, its current interdisciplinary richness and potential, and its central aims to challenge and transform structures and systems of power, privilege, and oppression. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Intersecting surface defects and two-dimensional CFT

NASA Astrophysics Data System (ADS)

Gomis, Jaume; Le Floch, Bruno; Pan, Yiwen; Peelaers, Wolfger

2017-08-01

We initiate the study of intersecting surface operators/defects in 4D 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 4D 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 two representations of S U (N ).

8. View inside Building 802, "Control Area", facing southeast. ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. View inside Building 802, "Control Area", facing southeast. - Naval Air Station Fallon, 100-man Fallout Shelter, 800 Complex, off Carson Road near intersection of Pasture & Berney Roads, Fallon, Churchill County, NV

The Intersection of Gender and Age: An Exploration

ERIC Educational Resources Information Center

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…

Long-Range Emergency Preemption of Traffic Lights

NASA Technical Reports Server (NTRS)

Bachelder, Aaron

2005-01-01

A forwarding system could prove beneficial as an addition to an electronic communication-and-control system that automatically modifies the switching of traffic lights to give priority to emergency vehicles. A system to which the forwarding system could be added could be any of a variety of emergency traffic-signal-preemption systems: these include systems now used in some municipalities as well as advanced developmental systems described in several NASA Tech Briefs articles in recent years. Because of a variety of physical and design limitations, emergency traffic-signal- preemption systems now in use are often limited in range to only one intersection at a time: in a typical system, only the next, closest intersection is preempted for an emergency vehicle. Simulations of gridlock have shown that such systems offer minimal advantages and can even cause additional delays. In analogy to what happens in fluid dynamics, the forwarding system insures that flow at a given location is sustained by guaranteeing downstream flow along the predicted route (typically a main artery) and intersecting routes (typically, side streets). In simplest terms, the forwarding system starts by taking note of any preemption issued by the preemption system to which it has been added. The forwarding system predicts which other intersections could be encountered by the emergency vehicle downstream of the newly preempted intersection. The system then forwards preemption triggers to those intersections. Beyond affording a right of way for the emergency vehicle at every intersection that lies ahead along any likely route from the current position of the vehicle, the forwarding system also affords the benefit of clearing congested roads far ahead of the vehicle. In a metropolitan environment with heavy road traffic, forwarding of preemption triggers could greatly enhance the performance of a pre-existing preemption system.

Cargos Rotate at Microtubule Intersections during Intracellular Trafficking.

PubMed

Gao, Yuan; Anthony, Stephen M; Yu, Yanqi; Yi, Yi; Yu, Yan

2018-06-19

Intracellular cargos are transported by molecular motors along actin and microtubules, but how their dynamics depends on the complex structure of the cytoskeletal network remains unclear. In this study, we investigated this longstanding question by measuring simultaneously the rotational and translational dynamics of cargos at microtubule intersections in living cells. We engineered two-faced particles that are fluorescent on one hemisphere and opaque on the other and used their optical anisotropy to report the rotation of cargos. We show that cargos undergo brief episodes of unidirectional and rapid rotation while pausing at microtubule intersections. Probability and amplitude of the cargo rotation depend on the geometry of the intersecting filaments. The cargo rotation is not random motion due to detachment from microtubules, as revealed by statistical analyses of the translational and rotational dynamics. Instead, it is an active rotation driven by motor proteins. Although cargos are known to pause at microtubule intersections, this study reveals a different dimension of dynamics at this seemingly static state and, more importantly, provides direct evidence showing the correlation between cargo rotation and the geometry of underlying microtubule intersections. Copyright © 2018 Biophysical Society. All rights reserved.

Analysis of Crossing Speed of the Pedestrians in Marked and Unmarked Crosswalks in the Signalized and Un-Signalized Intersections (Case Study: Rasht city)

NASA Astrophysics Data System (ADS)

Behbahani, Hamid; Najafi Moghaddam Gilani, Vahid; Jahangir Samet, Mehdi; Salehfard, Reza

2017-10-01

Pedestrians affect the traffic in the signalized and un-signalized intersections. Therefore, identifying the behavioural features of the pedestrians is of great importance and may result in better designing facilities for them. In this study, by shooting the four intersections in Rasht for 15 hours and inventory from 4568 pedestrians, crossing speed of the pedestrians in the marked crosswalks and unmarked crosswalks was evaluated and analysed. Results showed that pedestrians‧ crossing speed in the marked crosswalks is higher than their crossing speed in the unmarked crosswalks in both signalized and un-signalized intersections. Moreover, in the unmarked crosswalks in the signalized intersections, 15th percentile speed of male pedestrians, female pedestrians and group of pedestrians’ decrease 6.4%, 5.4% and 12.2%, respectively, compared with the 15th percentile speed in the marked crosswalks. Above-mentioned values in the unmarked crosswalks in the un-signalized intersections for male pedestrians, female pedestrians, and group of pedestrians decrease 1.2%, 3.8%, and 1.4%, respectively.

From "Buzzword" to Best Practice: Applying Intersectionality to Children Exposed to Intimate Partner Violence.

PubMed

Etherington, Nicole; Baker, Linda

2016-03-07

Empirical studies on the impact of intimate partner violence (IPV) on children have burgeoned over the last three decades. Notably absent from existing approaches to studying children exposed to IPV, however, is attention to how various positionalities intersect to impact the experiences of children and their families. In fact, while the importance of an intersectional framework for understanding IPV has been discussed for over two decades, little or no attention has been given to issues of children's exposure to IPV. In this article, we examine the current state of the literature on children exposed to IPV through an exploratory meta-analysis, finding limited application of intersectionality and a focus on discrete categories of difference. We then demonstrate why and how an intersectional framework should be applied to children exposed to IPV, with specific strategies for research and policy. We suggest a child-centered approach that recognizes diversity among children exposed to IPV, extending the challenge to traditional "one-size-fits-all" models to include an intersectionality-informed stance. © The Author(s) 2016.

The Benefit Impact of Air Pollution Reduction Through ATCS Implementation at Intersections

NASA Astrophysics Data System (ADS)

Budihardjo, Mochamad Arief; Huboyo, Haryono Setiyo; Samadikun, Budi Prasetyo

2018-02-01

The field study in five intersections that had ATCS, such as Krapyak, Tugu Muda, Polda, Bangkong and Fatmawati were done to investigate the effectivity of air pollution reduction. The study was done by estimating the differences between the vehicle speed due to the cycle duration of green light by field observation and video recording in each intersection. In five intersections that had been observed, the percentage of fuel consumption savings for two-wheeled vehicles were between 15 - 18%, meanwhile for four-wheel vehicles were between 30 - 46%. Based on the calculation that adopt the emission factor from CORINAIR and USEPA emission, the emission reduction based on pollutant types were TSP (12-17%), NOx (22-36%), CO (15-25%), HC (16-28%) and SO2 (22-35%). The result to the vehicles' speed that passed the intersections through ATCS has also indicated that the ATCS could increase vehicle speed and consequently reduce the emission.

Where to locate transit stops: Cross-intersection profiles of ultrafine particles and implications for pedestrian exposure.

PubMed

Choi, Wonsik; Ranasinghe, Dilhara; DeShazo, J R; Kim, Jae-Jin; Paulson, Suzanne E

2018-02-01

Epidemiological studies have shown that exposure to traffic-related pollutants increases incidence of adverse health outcomes. Transit users in cities across the globe commonly spend 15-45 min or more waiting at transit stops each day, often at locations with high levels of pollution from traffic. Here, we investigate the characteristics of concentration profiles of ultrafine particles (UFP) with 5 m spatial resolution across intersections, to determine the best place to site transit stops to minimize exposures. Cross-intersection UFP profiles were derived from 1744 profiles covering 90 m before and after each intersection center with a mobile monitoring platform. Measurements were made at 10 signalized intersections located at six urban sites, each with a distinct built environment, during both mornings and afternoons. Measurements were made within 1.5 m of the sidewalk and approximately at breathing height (1.5 m above ground level) to approximate sidewalk exposures. UFP profiles were strongly influenced by high emissions from vehicle stops and accelerations, and peaked within 30 m of intersection centers; from there concentrations decreased sharply with distance. Peak concentrations averaged about 90% higher than the minima along the block. They were accompanied by more frequent and larger transient concentration spikes, increasing the chance of people near the intersection being exposed to both short-term extremely high concentration spikes and higher average concentrations. The decays are somewhat larger before the intersection than after the intersection, however as siting transit stops after intersections is preferred for smooth traffic flow, we focus on after the intersection. Simple time-duration exposure calculations combined with breathing rates suggest moving a bus stop from 20 to 40-50 m after the intersection can reduce transit-users' exposure levels to total UFP substantially, in proportion to the reciprocal of the magnitude of elevation at the intersection. Copyright © 2017 Elsevier Ltd. All rights reserved.

Reductions in injury crashes associated with red light camera enforcement in oxnard, california.

PubMed

Retting, Richard A; Kyrychenko, Sergey Y

2002-11-01

This study estimated the impact of red light camera enforcement on motor vehicle crashes in one of the first US communities to employ such cameras-Oxnard, California. Crash data were analyzed for Oxnard and for 3 comparison cities. Changes in crash frequencies were compared for Oxnard and control cities and for signalized and nonsignalized intersections by means of a generalized linear regression model. Overall, crashes at signalized intersections throughout Oxnard were reduced by 7% and injury crashes were reduced by 29%. Right-angle crashes, those most associated with red light violations, were reduced by 32%; right-angle crashes involving injuries were reduced by 68%. Because red light cameras can be a permanent component of the transportation infrastructure, crash reductions attributed to camera enforcement should be sustainable.

An evaluation of Winnipeg's photo enforcement safety program: results of time series analyses and an intersection camera experiment.

PubMed

Vanlaar, Ward; Robertson, Robyn; Marcoux, Kyla

2014-01-01

The objective of this study was to evaluate the impact of Winnipeg's photo enforcement safety program on speeding, i.e., "speed on green", and red-light running behavior at intersections as well as on crashes resulting from these behaviors. ARIMA time series analyses regarding crashes related to red-light running (right-angle crashes and rear-end crashes) and crashes related to speeding (injury crashes and property damage only crashes) occurring at intersections were conducted using monthly crash counts from 1994 to 2008. A quasi-experimental intersection camera experiment was also conducted using roadside data on speeding and red-light running behavior at intersections. These data were analyzed using logistic regression analysis. The time series analyses showed that for crashes related to red-light running, there had been a 46% decrease in right-angle crashes at camera intersections, but that there had also been an initial 42% increase in rear-end crashes. For crashes related to speeding, analyses revealed that the installation of cameras was not associated with increases or decreases in crashes. Results of the intersection camera experiment show that there were significantly fewer red light running violations at intersections after installation of cameras and that photo enforcement had a protective effect on speeding behavior at intersections. However, the data also suggest photo enforcement may be less effective in preventing serious speeding violations at intersections. Overall, Winnipeg's photo enforcement safety program had a positive net effect on traffic safety. Results from both the ARIMA time series and the quasi-experimental design corroborate one another. However, the protective effect of photo enforcement is not equally pronounced across different conditions so further monitoring is required to improve the delivery of this measure. Results from this study as well as limitations are discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

Intersection of Intimate Partner Violence and HIV in Women

MedlinePlus

... and recommended data elements, version 1.0. Atlanta, GA: Centers for Disease Control and Prevention, National Center ... Sexual Violence Survey (NISVS): 2010 Summary Report. Atlanta, GA: National Center for Injury Prevention and Control, Centers ...

Improving Walkability Through Control Strategies at Signalized Intersections

DOT National Transportation Integrated Search

2017-01-01

As cities and communities nationwide seek to develop Complete Streets that foster livability and accommodate all modes, signal timing control strategies that include pedestrians in the operational decision process are gaining importance. This researc...

Subjective Discipline and the Social Control of Black Girls in Pipeline Schools

ERIC Educational Resources Information Center

Martin, Jennifer; Smith, Julia

2017-01-01

Using an intersectional feminist critical race lens, we utilized the Education Longitudinal Study (2002) data comparing tenth grade African American girls to White girls, analyzing whether the student was ever held back, teacher reports of problem behaviors in classrooms, and whether the student did not graduate from high school in the four years…

Refined open intersection numbers and the Kontsevich-Penner matrix model

NASA Astrophysics Data System (ADS)

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.

Enhancing Traffic Control Systems to Reduce Emissions and Fuel Consumption

DOT National Transportation Integrated Search

2016-06-01

This report contains four sub-reports on research tasks that were completed related to the enhancement of traffic control to reduce emissions and fuel consumption. The first task looks at the type of control to implement at an intersection, based on ...

Does My Story Belong? An Intersectional Critical Race Feminist Analysis of Student Silence in a Diverse Classroom

ERIC Educational Resources Information Center

Vaccaro, Annemarie

2017-01-01

This article offers an intersectional critical race feminist analysis of student silence in a diverse university classroom. Findings from a case study with six Women of Color and four White women revealed students remained silent because they felt their complicated intersectional realities did not fit with the acceptable classroom…

Data acquisition and processing system and method for investigating sub-surface features of a rock formation

DOEpatents

Vu, Cung Khac; Nihei, Kurt; Johnson, Paul A; Guyer, Robert; Ten Cate, James A; Le Bas, Pierre-Yves; Larmat, Carene S

2015-01-27

A system and a method includes generating a first signal at a first frequency; and a second signal at a second frequency. Respective sources are positioned within the borehole and controllable such that the signals intersect in an intersection volume outside the borehole. A receiver detects a difference signal returning to the borehole generated by a non-linear mixing process within the intersection volume, and records the detected signal and stores the detected signal in a storage device and records measurement parameters including a position of the first acoustic source, a position of the second acoustic source, a position of the receiver, elevation angle and azimuth angle of the first acoustic signal and elevation angle and azimuth angle of the second acoustic signal.

Expanding the Therapy Paradigm with Queer Couples: A Relational Intersectional Lens.

PubMed

Addison, Sheila M; Coolhart, Deborah

2015-09-01

North American and global cultures in general-and the field of Couple and Family Therapy in particular-have made significant strides toward recognizing and validating LGBTQ identities and relationships. However, clinical assessment and conceptualization of queer couples still lack the complexity needed to encompass the issues involved in treatment. Existing literature provides clinicians a basic understanding of queer couples and the dynamics that make them unique from nonqueer couples. However, much of this knowledge has been normed on White middle-class couples and has rarely included couples with transgender or bisexual members. This article invites clinicians and researchers to apply a feminist model of intersectionality to understand queer couples. Our proposed intersectional lens considers multiple axes of identity and power and their interrelationships (Crenshaw, 1989, 1991). We argue that intersectionality is important for understanding all identities, whether privileged or marginalized (Falicov, 2003). This application of the concept of intersectionality is unique in its relational focus, emphasizing how partners' complex individual identities overlap with and intersect with one another. Additionally, this lens considers how the therapists' and clients' multidimensional identities intersect. Three case studies are presented to illustrate application of the intersectional lens. In each case, exploring the partners' multiple social locations, their influences on one another, and the therapist's intersections of identity all proved critical to the direction of therapy. © 2015 Family Process Institute.

Intersectional inequalities in immunization in India, 1992-93 to 2005-06: a progress assessment.

PubMed

Joe, William

2015-05-01

Immunization in India is marked with stark disparities across gender, caste, wealth and place of residence with severe shortfalls among those disadvantaged in more than one dimension. In this regard, an explicit recognition of intersectionality and intersectional inequalities has 2-fold relevance; one, being the pathway of health inequality and the other being its role as a deterrent of progress particularly at higher (better) levels of health. Against this backdrop, this study examines intersectional inequalities in immunization in India and also suggests a level-sensitive progress assessment method. The study uses group analogue of Gini coefficient for highlighting the magnitude of intersectional inequality and for comprehending its association with immunization level. The results unravel the plight of vulnerable intersectional groups and draw attention to disquieting shortfalls among female SCST (scheduled castes and tribes) children from rural areas. There is also some evidence to indicate leveraging among rural males in matters of immunization and it is further discerned that such gender advantage is greater among rural non-SCST community than the rural SCST group. In concluding, the study calls for intensive immunization planning to improve coverage among vulnerable communities in both rural and urban areas. Published by Oxford University Press in association with The London School of Hygiene and Tropical Medicine © The Author 2014; all rights reserved.

Study and Optimization of Helicopter Subfloor Energy Absorption Structure with Foldcore Sandwich Structures

NASA Astrophysics Data System (ADS)

HuaZhi, Zhou; ZhiJin, Wang

2017-11-01

The intersection element is an important part of the helicopter subfloor structure. In order to improve the crashworthiness properties, the floor and the skin of the intersection element are replaced with foldcore sandwich structures. Foldcore is a kind of high-energy absorption structure. Compared with original structure, the new intersection element shows better buffering capacity and energy-absorption capacity. To reduce structure’s mass while maintaining the crashworthiness requirements satisfied, optimization of the intersection element geometric parameters is conducted. An optimization method using NSGA-II and Anisotropic Kriging is used. A significant CPU time saving can be obtained by replacing numerical model with Anisotropic Kriging surrogate model. The operation allows 17.15% reduce of the intersection element mass.

NASA Mars rover: a testbed for evaluating applications of covariance intersection

NASA Astrophysics Data System (ADS)

Uhlmann, Jeffrey K.; Julier, Simon J.; Kamgar-Parsi, Behzad; Lanzagorta, Marco O.; Shyu, Haw-Jye S.

1999-07-01

The Naval Research Laboratory (NRL) has spearheaded the development and application of Covariance Intersection (CI) for a variety of decentralized data fusion problems. Such problems include distributed control, onboard sensor fusion, and dynamic map building and localization. In this paper we describe NRL's development of a CI-based navigation system for the NASA Mars rover that stresses almost all aspects of decentralized data fusion. We also describe how this project relates to NRL's augmented reality, advanced visualization, and REBOT projects.

Felicity Conditions for Human Skill Acquisition: Validating an AI (Artificial Intelligence)-Based Theory.

DTIC Science & Technology

1983-11-01

a stack, and productions are often not grouped into subroutines. For some reason, when psychologists think of temporary memory, whether for control ...Sierra cannot gcncrate. ’I7he third group contains 76 bug sets that have non -empty intersections with at least one bug set from Sierra’s predictions. This...that have non -empty intersections when interesected with at least one observed bug set. ’Ibis third group of bug sets is printed a little differently

Feasibility Report. Mississippi River at Saint Paul, Minnesota. Reevaluation of Saint Paul Flood Control Project.

DTIC Science & Technology

1981-09-01

Jackson Street intersection to allow service vehicle access and passenger load- ing facilities at Lambert’s Landing across the river from the project...river from the project. Realignment of the Warner-Shepard Road, Sibley- Jackson Street intersection to allow service vehicle access and passenger...7-9 Ingersoll, F. G.: Member Jackson , J. N.: Member Jaggard, E. A.: Minnesota Supreme Court Justice Member 1890’s -1910’s, President 1893 James, H. C

Contributory factors to traffic crashes at signalized intersections in Hong Kong.

PubMed

Wong, S C; Sze, N N; Li, Y C

2007-11-01

Efficient geometric design and signal timing not only improve operational performance at signalized intersections by expanding capacity and reducing traffic delays, but also result in an appreciable reduction in traffic conflicts, and thus better road safety. Information on the incidence of crashes, traffic flow, geometric design, road environment, and traffic control at 262 signalized intersections in Hong Kong during 2002 and 2003 are incorporated into a crash prediction model. Poisson regression and negative binomial regression are used to quantify the influence of possible contributory factors on the incidence of killed and severe injury (KSI) crashes and slight injury crashes, respectively, while possible interventions by traffic flow are controlled. The results for the incidence of slight injury crashes reveal that the road environment, degree of curvature, and presence of tram stops are significant factors, and that traffic volume has a diminishing effect on the crash risk. The presence of tram stops, number of pedestrian streams, road environment, proportion of commercial vehicles, average lane width, and degree of curvature increase the risk of KSI crashes, but the effect of traffic volume is negligible.

Improved truck safety at traffic signals (phase A).

DOT National Transportation Integrated Search

2008-01-01

This project is developing new traffic signal control logic to improve the safety of heavy vehicles on high speed approaches to signalized intersections using wireless communications between the heavy vehicle and the traffic signal controller. The pr...

Adaptive Urban Signal Control and Integration (AUSCI) : evaluation final report

DOT National Transportation Integrated Search

2000-10-01

This report presents an evaluation of the Adaptive Urban Signal Control and Integration (AUSCI) Intelligent Transportation System (ITS) Field Operational Test in Minneapolis, Minnesota. The project involved a 56-intersection portion of Minneapolis, e...

11. ENGINE TEST CELL BUILDING INTERIOR. CONTROL ROOM FOR CELLS ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

11. ENGINE TEST CELL BUILDING INTERIOR. CONTROL ROOM FOR CELLS 2 AND 4. LOOKING SOUTHEAST. - Fairchild Air Force Base, Engine Test Cell Building, Near intersection of Arnold Street & George Avenue, Spokane, Spokane County, WA

Long-term exposure to high air pollution induces cumulative DNA damages in traffic policemen.

PubMed

Tan, Chaochao; Lu, Shijie; Wang, Yupeng; Zhu, Yan; Shi, Ting; Lin, Mingyue; Deng, Zhonghua; Wang, Zhu; Song, Nana; Li, Shuna; Yang, Pingting; Yang, Liyan; Liu, Yuanyuan; Chen, Zhiheng; Xu, Keqian

2017-09-01

The specific effects of long-term exposure to high air pollution on human health and biological remain unclear. To explore the adverse health effects as well as biological mechanisms and biomarkers for durative exposure to air pollution, 183 traffic policemen and 88 office policemen were enrolled in this study. The concentration of PM2.5 in both the traffic and office policemen's working environments were obtained. Detailed personal questionnaires were completed and levels of inflammation, oxidative stress and DNA damage markers of all participants were analyzed in this study. The average PM2.5 concentration of the intersections of main roads and the offices of control group were 132.4±48.9μg/m 3 and 50.80±38.6μg/m 3 , respectively. The traffic policemen, who stably exposed to at least 2 times higher PM2.5 in their work area as compared with the control group, have a median average duration of 7.00years, and average cumulative intersection duty time reached 8030h. No statistically significant differences in the levels of inflammation markers were observed between the traffic and office policemen. However, the DNA damage markers in traffic policemen shared significant positive correlation with cumulative intersection duty time and higher than those in the office policemen. Multiple linear regression analysis demonstrated that the increase of cumulative intersection duty time by 1h per day for one year was associated with the increase in 8-hydroxy-20-deoxyguanosine of 0.329% (95% CI: 0.249% to 0.409%), tail DNA of 0.051% (95% CI: 0.041% to 0.061%), micronucleus frequency of 0.036‰ (95% CI: 0.03‰ to 0.043‰), and a decrease in glutathione of 0.482% (95% CI: -0.652% to -0.313%). These findings suggest that long-term exposure to high air pollution could induce cumulative DNA damages, supporting the hypothesis that durative exposure to air pollution is associated with an increased risk of cancer. Copyright © 2017 Elsevier B.V. All rights reserved.

REVIEWS OF TOPICAL PROBLEMS: Application of cybernetic methods in physics

NASA Astrophysics Data System (ADS)

Fradkov, Aleksandr L.

2005-02-01

Basic aspects of the subject and methodology for a new and rapidly developing area of research that has emerged at the intersection of physics and control theory (cybernetics) and emphasizes the application of cybernetic methods to the study of physical systems are reviewed. Speed-gradient and Hamiltonian solutions for energy control problems in conservative and dissipative systems are presented. Application examples such as the Kapitza pendulum, controlled overcoming of a potential barrier, and controlling coupled oscillators and molecular systems are presented. A speed-gradient approach to modeling the dynamics of physical systems is discussed.

Applying Bayesian hierarchical models to examine motorcycle crashes at signalized intersections.

PubMed

Haque, Md Mazharul; Chin, Hoong Chor; Huang, Helai

2010-01-01

Motorcycles are overrepresented in road traffic crashes and particularly vulnerable at signalized intersections. The objective of this study is to identify causal factors affecting the motorcycle crashes at both four-legged and T signalized intersections. Treating the data in time-series cross-section panels, this study explores different Hierarchical Poisson models and found that the model allowing autoregressive lag-1 dependence specification in the error term is the most suitable. Results show that the number of lanes at the four-legged signalized intersections significantly increases motorcycle crashes largely because of the higher exposure resulting from higher motorcycle accumulation at the stop line. Furthermore, the presence of a wide median and an uncontrolled left-turn lane at major roadways of four-legged intersections exacerbate this potential hazard. For T signalized intersections, the presence of exclusive right-turn lane at both major and minor roadways and an uncontrolled left-turn lane at major roadways increases motorcycle crashes. Motorcycle crashes increase on high-speed roadways because they are more vulnerable and less likely to react in time during conflicts. The presence of red light cameras reduces motorcycle crashes significantly for both four-legged and T intersections. With the red light camera, motorcycles are less exposed to conflicts because it is observed that they are more disciplined in queuing at the stop line and less likely to jump start at the start of green.

A new construction of Calabi-Yau manifolds: Generalized CICYs

NASA Astrophysics Data System (ADS)

Anderson, Lara B.; Apruzzi, Fabio; Gao, Xin; Gray, James; Lee, Seung-Joo

2016-05-01

We present a generalization of the complete intersection in products of projective space (CICY) construction of Calabi-Yau manifolds. CICY three-folds and four-folds have been studied extensively in the physics literature. Their utility stems from the fact that they can be simply described in terms of a 'configuration matrix', a matrix of integers from which many of the details of the geometries can be easily extracted. The generalization we present is to allow negative integers in the configuration matrices which were previously taken to have positive semi-definite entries. This broadening of the complete intersection construction leads to a larger class of Calabi-Yau manifolds than that considered in previous work, which nevertheless enjoys much of the same degree of calculational control. These new Calabi-Yau manifolds are complete intersections in (not necessarily Fano) ambient spaces with an effective anticanonical class. We find examples with topology distinct from any that has appeared in the literature to date. The new manifolds thus obtained have many interesting features. For example, they can have smaller Hodge numbers than ordinary CICYs and lead to many examples with elliptic and K3-fibration structures relevant to F-theory and string dualities.

Two innovative healthcare technologies at the intersection of serious games, alternative realities, and play therapy.

PubMed

Brahnam, Sheryl; Brooks, Anthony L

2014-01-01

Using game technologies and digital media for improving physical and mental health and for the therapeutic benefit and well-being of a wide range of people is an area of study that is rapidly expanding. Much research in this emerging field is centered at the intersection of serious games, alternative realities, and play therapy. In this paper the authors describe their transdisciplinary work at this intersection: i) an integrative system of psychotherapy technologies called MyPsySpace currently being prototyped in Second Life with the aim of offering new and virtual translations of traditional expressive therapies (virtual sandplay, virtual drama therapy, digital expressive therapy, and virtual safe spaces) and ii) a mature body of research entitled SoundScapes that is exploring the use of interactive video games and abstract creative expression (making music, digital painting, and robotic device control) as a supplement to traditional physical rehabilitation intervention. Aside from introducing our work to a broader audience, our goal is to encourage peers to investigate ideas that reach across disciplines-to both risk and reap the benefits of combining technologies, theories, and methods stemming from multiple disciplines.

An Introductory Mixed-Methods Intersectionality Analysis of College Access and Equity: An Examination of First-Generation Asian Americans and Pacific Islanders

ERIC Educational Resources Information Center

Museus, Samuel D.

2011-01-01

In this article, the author discusses how researchers can use mixed-methods approaches and intersectional analyses to understand college access among first-generation Asian American and Pacific Islanders (AAPIs). First, he discusses the utility of mixed-methods approaches and intersectionality research in studying college access. Then, he…

Intersectionality of HIV stigma and masculinity in eastern Uganda: implications for involving men in HIV programmes.

PubMed

Mburu, Gitau; Ram, Mala; Siu, Godfrey; Bitira, David; Skovdal, Morten; Holland, Paula

2014-10-11

Stigma is a determinant of social and health inequalities. In addition, some notions of masculinity can disadvantage men in terms of health outcomes. However, few studies have explored the extent to which these two axes of social inequality intersect to influence men's health outcomes. This paper investigates the intersection of HIV stigma and masculinity, and its perceived impact on men's participation in and utilisation of HIV services in Uganda. Interviews and focus group discussions were conducted in Mbale and Jinja districts of Uganda between June and October 2010. Participants were men and women living with HIV (n = 40), their family members (n = 10) and health providers (n = 15). Inductive analysis was used to identify mechanisms through which stigma and masculinity were linked. Our findings showed that HIV stigma and masculinity did not exist as isolated variables, but as intersecting phenomena that influenced men's participation in HIV services. Specifically, HIV stigma threatened masculine notions of respectability, independence and emotional control, while it amplified men's risk-taking. As a result, the intersection of masculinity and HIV stigma prevented some men from i) seeking health care and accepting a 'sick role'; ii) fulfilling their economic family responsibilities; iii) safeguarding their reputation and respectability; iv) disclosing their HIV status; and v) participating in peer support groups. Participation in some peer support activities was considered a female trait and it also exacerbated HIV stigma as it implicitly singled out those with HIV. In contrast, inclusion of income-generating activities in peer support groups encouraged men's involvement as it enabled them to provide for their families, cushioned them from HIV stigma, and in the process, provided them with an opportunity to redeem their reputation and respectability. To improve men's involvement in HIV services, the intersection between HIV stigma and masculinity should be considered. In particular, better integration of and linkage between gender transformative interventions that support men to reconstruct their male identities and reject signifiers of masculinity that prevent their access to HIV services, and stigma-reduction interventions that target social and structural drivers of stigma is required within HIV programmes.

Time-series analysis to study the impact of an intersection on dispersion along a street canyon.

PubMed

Richmond-Bryant, Jennifer; Eisner, Alfred D; Hahn, Intaek; Fortune, Christopher R; Drake-Richman, Zora E; Brixey, Laurie A; Talih, M; Wiener, Russell W; Ellenson, William D

2009-12-01

This paper presents data analysis from the Brooklyn Traffic Real-Time Ambient Pollutant Penetration and Environmental Dispersion (B-TRAPPED) study to assess the transport of ultrafine particulate matter (PM) across urban intersections. Experiments were performed in a street canyon perpendicular to a highway in Brooklyn, NY, USA. Real-time ultrafine PM samplers were positioned on either side of an intersection at multiple locations along a street to collect time-series number concentration data. Meteorology equipment was positioned within the street canyon and at an upstream background site to measure wind speed and direction. Time-series analysis was performed on the PM data to compute a transport velocity along the direction of the street for the cases where background winds were parallel and perpendicular to the street. The data were analyzed for sampler pairs located (1) on opposite sides of the intersection and (2) on the same block. The time-series analysis demonstrated along-street transport, including across the intersection when background winds were parallel to the street canyon and there was minimal transport and no communication across the intersection when background winds were perpendicular to the street canyon. Low but significant values of the cross-correlation function (CCF) underscore the turbulent nature of plume transport along the street canyon. The low correlations suggest that flow switching around corners or traffic-induced turbulence at the intersection may have aided dilution of the PM plume from the highway. This observation supports similar findings in the literature. Furthermore, the time-series analysis methodology applied in this study is introduced as a technique for studying spatiotemporal variation in the urban microscale environment.

Evolving Norms at the Intersection of Health and Trade

PubMed Central

Drope, Jeffrey; Lencucha, Raphael

2014-01-01

There has been growing tension at the intersection of health and economic policymaking as global governance has increased across sectors. This tension has been particularly evident between tobacco control and trade policy, as the international norms that frame them – particularly the Framework Convention on Tobacco Control and the World Trade Organization (WTO) – have continued to institutionalize. Using five case studies of major tobacco-related trade disputes from the principal multilateral system of trade governance – the WTO/General Agreement on Tariffs and Trade – we trace the evolution of these interacting norms over nearly 25 years. Our analytic framework particularly focuses on the actors that advance, defend and challenge these norms. We find that an increasingly broad network, which includes governments, intergovernmental organizations, non-governmental organizations and members of the epistemic community, is playing a more active role in seeking to resolve these tensions. Moreover, key economic actors are beginning to incorporate health more actively in their messaging and activities. We also demonstrate that the most recent resonant messages reflect a more nuanced integration of the two norms. The tobacco control example has direct relevance to related policy areas, including environment, safety, access to medicines, diet, and alcohol. PMID:24603086

An Alternative for Emergency Preemption of Traffic Lights

NASA Technical Reports Server (NTRS)

Foster, Conrad; Bachelder, Aaron

2006-01-01

An electronic communication-and-control system has been developed as a prototype of advanced means of automatically modifying the switching of traffic lights to give priority to emergency vehicles. This system could be used alternatively or in addition to other emergency traffic-light-preemption systems, including a variety of systems now in use as well as two proposed systems described in "Systems Would Preempt Traffic Lights for Emergency Vehicles" (NPO-30573), NASA Tech Briefs, Vol. 28, No. 10 (October 2004), page 36. Unlike those prior systems that depend on detection of sounds and/or lights emitted by emergency vehicles, this system is not subject to severe range limitations. This system can be retrofitted into any pre-existing traffic-light-control system, without need to modify that system other than to make a minimal number of wire connections between the two systems. This system comprises several subsystems, including a transponder and interface circuitry on each emergency vehicle, a monitoring and control unit at each intersection equipped with traffic lights, and a wide-area two-way radio communication network that connects the emergency vehicles and intersection units. Computers in the various intersections and vehicle units run special-purpose software that implements the traffic- light-preemption scheme. The operations of the intersection and vehicle units are synchronized by use of Global Positioning System (GPS) timing signals. The transponder in each vehicle estimates its own position and velocity by use of GPS signals, deductive ("dead") reckoning, data from the onboard diagnostic (OBD) computer of the vehicle, and/or triangulation of beacon signals. When the operator of an emergency vehicle turns on its flashing lights and sirens in response to a request for an emergency response, the transponder unit goes into action, reading the OBD data to determine speed and acceleration, and reading and gathering further navigational data as described above. The position, velocity, and acceleration data are combined with vehicle-identification data in a prescribed format, and the resulting set of data is transmitted to the intersections within communication range of the transponder.

3. OBLIQUE VIEW OF THE PRESENT CONTROL ROOM (ORIGINALLY THE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. OBLIQUE VIEW OF THE PRESENT CONTROL ROOM (ORIGINALLY THE TRANSFORMER ROOM). - Washington Water Power Company Post Falls Power Plant, Middle Channel Powerhouse & Dam, West of intersection of Spokane & Fourth Streets, Post Falls, Kootenai County, ID

12. ENGINE TEST CELL BUILDING INTERIOR. DETAIL OF CONTROL CONSOLE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

12. ENGINE TEST CELL BUILDING INTERIOR. DETAIL OF CONTROL CONSOLE FOR ENGINE TEST CELL 4. LOOKING NORTH. - Fairchild Air Force Base, Engine Test Cell Building, Near intersection of Arnold Street & George Avenue, Spokane, Spokane County, WA

Delay correction model for estimating bus emissions at signalized intersections based on vehicle specific power distributions.

PubMed

Song, Guohua; Zhou, Xixi; Yu, Lei

2015-05-01

The intersection is one of the biggest emission points for buses and also the high exposure site for people. Several traffic performance indexes have been developed and widely used for intersection evaluations. However, few studies have focused on the relationship between these indexes and emissions at intersections. This paper intends to propose a model that relates emissions to the two commonly used measures of effectiveness (i.e. delay time and number of stops) by using bus activity data and emission data at intersections. First, with a large number of field instantaneous emission data and corresponding activity data collected by the Portable Emission Measurement System (PEMS), emission rates are derived for different vehicle specific power (VSP) bins. Then, 2002 sets of trajectory data, an equivalent of about 140,000 sets of second-by-second activity data, are obtained from Global Position Systems (GPSs)-equipped diesel buses in Beijing. The delay and the emission factors of each trajectory are estimated. Then, by using baseline emission factors for two types of intersections, e.g. the Arterial @ Arterial Intersection and the Arterial @ Collector, delay correction factors are calculated for the two types of intersections at different congestion levels. Finally, delay correction models are established for adjusting emission factors for each type of intersections and different numbers of stops. A comparative analysis between estimated and field emission factors demonstrates that the delay correction model is reliable. Copyright © 2015 Elsevier B.V. All rights reserved.

The Problem With the Phrase Women and Minorities: Intersectionality—an Important Theoretical Framework for Public Health

PubMed Central

2012-01-01

Intersectionality is a theoretical framework that posits that multiple social categories (e.g., race, ethnicity, gender, sexual orientation, socioeconomic status) intersect at the micro level of individual experience to reflect multiple interlocking systems of privilege and oppression at the macro, social-structural level (e.g., racism, sexism, heterosexism). Public health’s commitment to social justice makes it a natural fit with intersectionality’s focus on multiple historically oppressed populations. Yet despite a plethora of research focused on these populations, public health studies that reflect intersectionality in their theoretical frameworks, designs, analyses, or interpretations are rare. Accordingly, I describe the history and central tenets of intersectionality, address some theoretical and methodological challenges, and highlight the benefits of intersectionality for public health theory, research, and policy. PMID:22594719

Why the 2002 Denali fault rupture propagated onto the Totschunda fault: implications for fault branching and seismic hazards

USGS Publications Warehouse

Schwartz, David P.; Haeussler, Peter J.; Seitz, Gordon G.; Dawson, Timothy E.

2012-01-01

The propagation of the rupture of the Mw7.9 Denali fault earthquake from the central Denali fault onto the Totschunda fault has provided a basis for dynamic models of fault branching in which the angle of the regional or local prestress relative to the orientation of the main fault and branch plays a principal role in determining which fault branch is taken. GeoEarthScope LiDAR and paleoseismic data allow us to map the structure of the Denali-Totschunda fault intersection and evaluate controls of fault branching from a geological perspective. LiDAR data reveal the Denali-Totschunda fault intersection is structurally simple with the two faults directly connected. At the branch point, 227.2 km east of the 2002 epicenter, the 2002 rupture diverges southeast to become the Totschunda fault. We use paleoseismic data to propose that differences in the accumulated strain on each fault segment, which express differences in the elapsed time since the most recent event, was one important control of the branching direction. We suggest that data on event history, slip rate, paleo offsets, fault geometry and structure, and connectivity, especially on high slip rate-short recurrence interval faults, can be used to assess the likelihood of branching and its direction. Analysis of the Denali-Totschunda fault intersection has implications for evaluating the potential for a rupture to propagate across other types of fault intersections and for characterizing sources of future large earthquakes.

Intersection assistance: a safe solution for older drivers?

PubMed

Dotzauer, Mandy; Caljouw, Simone R; de Waard, Dick; Brouwer, Wiebo H

2013-10-01

Within the next few decades, the number of older drivers operating a vehicle will increase rapidly (Eurostat, 2011). As age increases so does physical vulnerability, age-related impairments, and the risk of being involved in a fatal crashes. Older drivers experience problems in driving situations that require divided attention and decision making under time pressure as reflected by their overrepresentation in at-fault crashes on intersections. Advanced Driver Assistance Systems (ADAS) especially designed to support older drivers crossing intersections might counteract these difficulties. In a longer-term driving simulator study, the effects of an intersection assistant on driving were evaluated. 18 older drivers (M=71.44 years) returned repeatedly completing a ride either with or without a support system in a driving simulator. In order to test the intersection assistance, eight intersections were depicted for further analyses. Results show that ADAS affects driving. Equipped with ADAS, drivers allocated more attention to the road center rather than the left and right, crossed intersections in shorter time, engaged in higher speeds, and crossed more often with a critical time-to-collision (TTC) value. The implications of results are discussed in terms of behavioral adaptation and safety. Copyright © 2013 Elsevier Ltd. All rights reserved.

Understanding the micro and macro politics of health: Inequalities, intersectionality & institutions - A research agenda.

PubMed

Gkiouleka, Anna; Huijts, Tim; Beckfield, Jason; Bambra, Clare

2018-03-01

This essay brings together intersectionality and institutional approaches to health inequalities, suggesting an integrative analytical framework that accounts for the complexity of the intertwined influence of both individual social positioning and institutional stratification on health. This essay therefore advances the emerging scholarship on the relevance of intersectionality to health inequalities research. We argue that intersectionality provides a strong analytical tool for an integrated understanding of health inequalities beyond the purely socioeconomic by addressing the multiple layers of privilege and disadvantage, including race, migration and ethnicity, gender and sexuality. We further demonstrate how integrating intersectionality with institutional approaches allows for the study of institutions as heterogeneous entities that impact on the production of social privilege and disadvantage beyond just socioeconomic (re)distribution. This leads to an understanding of the interaction of the macro and the micro facets of the politics of health. Finally, we set out a research agenda considering the interplay/intersections between individuals and institutions and involving a series of methodological implications for research - arguing that quantitative designs can incorporate an intersectional institutional approach. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Complicating Counterspaces: Intersectionality and the Michigan Womyn's Music Festival.

PubMed

McConnell, Elizabeth A; Todd, Nathan R; Odahl-Ruan, Charlynn; Shattell, Mona

2016-06-01

The counterspaces framework articulated by Case and Hunter (2012), follows from community psychology's long-standing interest in the potential for settings to promote well-being and liberatory responses to oppression. This framework proposes that certain settings (i.e., "counterspaces") facilitate a specific set of processes that promote the well-being of marginalized groups. We argue that an intersectional analysis is crucial to understand whether and how counterspaces achieve these goals. We draw from literature on safe spaces and present a case study of the Michigan Womyn's Music Festival (Michfest) to illustrate the value of an intersectional analysis and explore how these processes operate. Based on 20 in-person interviews, 23 responses to an online survey, and ethnographic field notes, we show how Michfest was characterized by a particular intersection of identities at the setting level, and intersectional diversity complicated experiences at the individual level. Moreover, intersectional identities provided opportunities for dialogue and change at the setting level, including the creation of counterspaces within counterspaces. Overall, we demonstrate the need to attend to intersectionality in counterspaces, and more broadly in how we conceptualize settings in community psychology. © Society for Community Research and Action 2016.

RHODES-ITMS Tempe field test project : implementation and field testing of RHODES, a real-time traffic adaptive control system

DOT National Transportation Integrated Search

2001-09-01

RHODES is a traffic-adaptive signal control system that optimally controls the traffic that is observed in real time. The RHODES-ITMS Program is the application of the RHODES strategy for the two intersections of a freeway-arterial diamond interchang...

Evaluation of adaptive signal control technology--volume 1 : before-conditions data collection and analysis.

DOT National Transportation Integrated Search

2017-04-01

Field evaluation of adaptive signal control technologies (ASCT) is very important in understanding the systems contribution to safety : and operational efficiency. Data were collected at six intersections along the Neil Street corridor in Champaig...

10 Best resources on… intersectionality with an emphasis on low- and middle-income countries.

PubMed

Larson, Elizabeth; George, Asha; Morgan, Rosemary; Poteat, Tonia

2016-10-01

Intersectionality has emerged as an important framework for understanding and responding to health inequities by making visible the fluid and interconnected structures of power that create them. It promotes an understanding of the dynamic nature of the privileges and disadvantages that permeate health systems and affect health. It considers the interaction of different social stratifiers (e.g. 'race'/ethnicity, indigeneity, gender, class, sexuality, geography, age, disability/ability, migration status, religion) and the power structures that underpin them at multiple levels. In doing so, it is a departure from previous health inequalities research that looked at these forms of social stratification in isolation from one another or in an additive manner. Despite its potential use and long history in other disciplines, intersectionality is uncommonly used in health systems research in low- and middle-income countries (LMICs). To orient readers to intersectionality theory and research, we first define intersectionality and describe its role in public health, and then we review resources on intersectionality. We found that applications in public health mostly increased after 2009, with only 14 out of 86 articles focused on LMICs. To arrive at 10 best resources, we selected articles based on the proportion of the article that was devoted to intersectionality, the strength of the intersectionality analysis, and its relevance to LMICs. The first four resources explain intersectionality as a methodology. The subsequent six articles apply intersectionality to research in LMIC with quantitative and qualitative analysis. We provide examples from India, Swaziland, Uganda and Mexico. Topics for the studies range from HIV, violence and sexual abuse to immunization and the use of health entitlements. Through these 10 resources, we hope to spark interest and open a needed conversation on the importance and use of intersectional analysis in LMICs as part of understanding people-centred health systems. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Thumb-actuated two-axis controller

NASA Technical Reports Server (NTRS)

Hollow, R. H. (Inventor)

1986-01-01

A two axis joystick controller is described. It produces at least one output signal in relation to pivotal displacement of a member with respect to an intersection of the two axes. The member is pivotally movable on a support with respect to the two axes. The support has a centrally disposed aperture. A light source is mounted on the pivotally movable member above the aperture to direct light through the aperture. A light sensor is mounted below the aperture in the support at the intersection of the two axes to receive the light from the light source directed through the aperture. The light sensor produces at least one output signal related to a location on the sensor at which the light from the light source strikes the sensor.

Traffic flow collection wireless sensor network node for intersection light control

NASA Astrophysics Data System (ADS)

Li, Xu; Li, Xue

2011-10-01

Wireless sensor network (WSN) is expected to be deployed in intersection to monitor the traffic flow continuously, and the monitoring datum can be used as the foundation of traffic light control. In this paper, a WSN based on ZigBee protocol for monitoring traffic flow is proposed. Structure, hardware and work flow of WSN nodes are designed. CC2431 from Texas Instrument is chosen as the main computational and transmission unit, and CC2591 as the amplification unit. The stability experiment and the actual environment experiment are carried out in the last of the paper. The results of experiments show that WSN has the ability to collect traffic flow information quickly and transmit the datum to the processing center in real time.

Vehicle Transponder for Preemption of Traffic Lights

NASA Technical Reports Server (NTRS)

Foster, Conrad; Bachelder, Aaron

2006-01-01

The purpose of this article is to describe, in more detail, the transponder installed in each vehicle that participates in the emergency traffic-light-preemption system described in the immediately preceding article. The transponder (see figure) is a fully autonomous data--collection, data-processing, information-display, and communication subsystem that performs robustly in preemption of traffic lights and monitoring of the statuses of street intersections. This transponder monitors the condition of the emergency vehicle in which it is installed and determines when the vehicle has been placed in an emergency-response condition with its siren and/or warning lights activated. Upon detection of such a condition, the transponder collects real-time velocity and acceleration data from the onboard diagnostic (OBD) computer of the vehicle. For this purpose, the transponder contains an OBD interface circuit, including a microprocessor that determines the manufacturer and model of the vehicle and then sends the appropriate commands to the OBD computer requesting the speed and acceleration data. At the same time, data from an onboard navigation system are collected to determine the location and the heading of the vehicle. Then acceleration, speed, position, and heading data are processed and combined with a vehicle-identification number and the resulting set of data is transmitted to monitoring and control units located at all intersections within communication range. When the unit at an intersection determines that this vehicle is approaching and has priority to preempt the intersection, it transmits a signal declaring the priority and the preemption to all participating vehicles (including this one) in the vicinity. If the unit at the intersection has determined that other participating vehicles are also approaching the intersection, then this unit also transmits, to the vehicle that has priority, a message that the other vehicles are approaching the same intersection. The texts of these messages, plus graphical symbols that show the directions and numbers of the approaching vehicles, are presented on the display panel of a computer that is part of the transponder.

Intertwined effects of gender and migration status on persistence in SET study programmes

NASA Astrophysics Data System (ADS)

Guenther, Elisabeth Anna; Koeszegi, Sabine Theresia

2017-11-01

This paper explores the intersectional interference of gender and migration status on students' persistence at an Austrian University of Technology. While controlling for the pre-university education and performance indicators, we estimate the odds for the persistence of male and female students, as well as of students with diverse migration statuses. We use the enrolment data of students from 1998 to 2010. The analysis reveals remarkable and significant effects of gender and migration status, as well as intersectional interference effects from both social categories on persistence. Female and students with immigration status are less likely to persist, even if performance and previous relevant experiences are controlled. A segregated analysis of the student population sheds further light on the interlocked and entangled effects of the social ascriptions underlying gender and migration status. The analysis supports the proposition of the accumulation of (dis-)advantages along students' careers. The profound quantification of gender and migration status effects can be utilised as basis for further research and purposeful policy measures to increase persistence in Science, Engineering and Technology for students with diverse backgrounds.

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

NASA Astrophysics Data System (ADS)

Yu, Shao-Wei; Shi, Zhong-Ke

2015-01-01

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

Evidence-based medicine at the intersection of research interests between academic health sciences librarians and medical educators: a review of the literature.

PubMed

Dorsch, Josephine L; Perry, Gerald Jerry

2012-10-01

In 2008, the Association of Academic Health Sciences Libraries established an Education Research Task Force (ERTF) to plan research addressing research priorities outlined in key Association of American Medical Colleges reports. ERTF members conducted a literature review to describe the state of collaborative research at the intersection of medical education and health sciences librarianship. Analysis of initial results revealed instruction in evidence-based medicine (EBM) was a shared interest and is thus the focus of this review. Searches on EBM teaching programs were conducted, and results were posted to a shared online citation management service. Individual articles were assessed and assigned metadata describing subject matter, scope, and format. Article analysis identified key themes. Most papers were descriptive narratives of curricular development. Evaluation studies were also prominent and often based on student satisfaction or self-reported competency. A smaller number of controlled studies provide evidence of impacts of librarian involvement in EBM instruction. Scholarship of EBM instruction is of common interest between medical educators and health sciences librarians. Coauthorship between the groups and distribution of literature points to a productive collaboration. An emerging literature of controlled studies measuring the impact of cross-disciplinary efforts signals continued progress in the arena of EBM instruction.

Evidence-based medicine at the intersection of research interests between academic health sciences librarians and medical educators: a review of the literature

PubMed Central

Dorsch, Josephine L.; Perry, Gerald (Jerry)

2012-01-01

Objectives: In 2008, the Association of Academic Health Sciences Libraries established an Education Research Task Force (ERTF) to plan research addressing research priorities outlined in key Association of American Medical Colleges reports. ERTF members conducted a literature review to describe the state of collaborative research at the intersection of medical education and health sciences librarianship. Analysis of initial results revealed instruction in evidence-based medicine (EBM) was a shared interest and is thus the focus of this review. Methods: Searches on EBM teaching programs were conducted, and results were posted to a shared online citation management service. Individual articles were assessed and assigned metadata describing subject matter, scope, and format. Results: Article analysis identified key themes. Most papers were descriptive narratives of curricular development. Evaluation studies were also prominent and often based on student satisfaction or self-reported competency. A smaller number of controlled studies provide evidence of impacts of librarian involvement in EBM instruction. Conclusions: Scholarship of EBM instruction is of common interest between medical educators and health sciences librarians. Coauthorship between the groups and distribution of literature points to a productive collaboration. An emerging literature of controlled studies measuring the impact of cross-disciplinary efforts signals continued progress in the arena of EBM instruction. PMID:23133324

Computer Generated Pictorial Stores Management Displays for Fighter Aircraft.

DTIC Science & Technology

1983-05-01

questionnaire rating-scale data. KRISHNAIAH FINITE INTERSECTION TESTS (FITs) - A set of tests conducted after significant MANOVA results are found to...the Social Sciences (SPSS) (Reference 2). To further examine significant performance differences, the Krishnaiah Finite Intersection Test (FIT), a...New York: McGraw-Hill Book Company, 1975. 3. C. M. Cox, P. R. Krishnaiah , J. C. Lee, J. M. Reising, and F. J. Schuurman, A study on Finite Intersection

Heat Sink Welding for Preventing Hot Cracking in Alloy 2195 Intersection Welds: A Feasibility Study

NASA Technical Reports Server (NTRS)

Yang, Yu-Ping; Dong, Pingsha; Rogers, Patrick

2000-01-01

Two concepts, stationary cooling and trailing cooling, were proposed to prevent weld intersection cracking. Finite element analysis was used to demonstrate the potential effectiveness of those two concepts. Both stationary and trailing heat sink setups were proposed for preventing intersection cracking. The cooling media could be liquid nitrogen, or pressured air knife. Welding experiments on the small test panel with the localized heat sink confirmed the feasibility of using such a stationary cooling technique. The required cooling was achieved in this test panel. Systematic welding experiments should be conducted in the future to validate and refine the heat sink technique for preventing intersection cracking.

The role of intersection and street design on severity of bicycle-motor vehicle crashes

PubMed Central

Verma, Santosh; Mekary, Rania A; Courtney, Theodore K; Christiani, David C

2017-01-01

Background Safety concerns are a major barrier to cycling. Intersection and street design variables such as intersection angles and street width might contribute to the severity of crashes and the safety concerns. In this study we examined whether these design variables were associated with bicycle-motor vehicle crashes (BMVC) severity. Methods Using the geographical information system and latitudes/longitudes recorded by the police using a global positioning device, we extracted intersection angles, street width, bicycle facilities, posted speed limits and annual average daily traffic from 3266 BMVC data from New York City police records. Additional variables about BMVC, including age and sex of the bicyclist, time of the day, road surface conditions, road character, vehicle type and injury severity, were obtained from police reports. Injury severity was classified as severe (incapacitating or killed) or non-severe (non-incapacitating, possible injury). The associations between injury severity and environment design variables were examined using multivariate log-binomial regression model. Findings Compared with crashes at orthogonal intersections, crashes at non-orthogonal intersections had 1.37 times (95% CI 1.05 to 1.80) and non-intersection street segments had 1.31 times (95% CI 1.01 to 1.70) higher risk of a severe injury. Crashes that involved a truck or a bus were twice as likely to result in a severe injury outcome; street width was not significantly associated with injury severity. Conclusion Crashes at non-orthogonal intersections and non-intersection segments are more likely to result in higher injury severity. The findings can be used to improve road design and develop effective safety interventions. PMID:27881469

Examining the Intersection of Bullying and Physical Relationship Violence Among New York City High School Students.

PubMed

Peters, Zachary J; Hatzenbuehler, Mark L; Davidson, Leslie L

2017-01-01

Research is just beginning to explore the intersection of bullying and relationship violence. The relationship between these forms of youth aggression has yet to be examined in diverse urban centers, including New York City (NYC). This study seeks to identify intersections of joint victimization from bullying and electronic bullying (e-bullying) with physical relationship violence (pRV). This study examines data from the NYC Youth Risk Behavior Survey (YRBS), a representative sample of NYC public high school students, to assess the concurrent victimization from bullying at school and e-bullying with pRV, operationalized as physical violence by a dating partner in the past 12 months. Students who reported being bullied at school and e-bullied had increased odds (bullied: OR = 2.5, 95% CI [2.1, 2.9]; e-bullied: OR = 3.0, 95% CI [2.6, 3.5]) of also being victimized by pRV compared with those who did not report being bullied or e-bullied. In logistic regression models, being bullied at school and being e-bullied remained significant predictors of students' odds of reporting pRV (bullied: AOR = 2.6, 95% CI [2.2, 3.1]; e-bullied: AOR = 3.0, 95% CI [2.5, 3.6]) while controlling for race, gender, sexual orientation, and age. This research is the first to assess the intersection of victimization from bullying and e-bullying with pRV in a large, diverse, random sample of urban high school students. In this sample, students who report being bullied or e-bullied are more likely also to report pRV than students who have not been bullied or e-bullied. This research has potential implications for educators, adolescent health and social service providers, and policy makers to tailor programs and enact policies that jointly address bullying and pRV. Future studies are needed to longitudinally assess both victimization from and perpetration of bullying and pRV. © The Author(s) 2015.

Investigating the Intersection of Race and Histories in the Classroom

ERIC Educational Resources Information Center

Martell, Christopher C.

2012-01-01

In this practitioner research study, a social studies teacher examined the intersection between his students' race/ethnicity and their experiences learning history. Using the theory of culturally relevant pedagogy as a lens, this study employed mixed methods, analyzing teacher journaling, classroom artifacts, and student reflections, as well as…

Development of pedestrian safety based warrants for permissive left-turn control

DOT National Transportation Integrated Search

2010-12-01

At the intersections with permissive only signal control, pedestrians will move at the permissive phase with the parallel through vehicular movement and left-turn vehicles, the left-turn vehicles have to yield to both opposing through vehicles and pe...

3-Dimensional Geologic Modeling Applied to the Structural Characterization of Geothermal Systems: Astor Pass, Nevada, USA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Siler, Drew L; Faulds, James E; Mayhew, Brett

2013-04-16

Geothermal systems in the Great Basin, USA, are controlled by a variety of fault intersection and fault interaction areas. Understanding the specific geometry of the structures most conducive to broad-scale geothermal circulation is crucial to both the mitigation of the costs of geothermal exploration (especially drilling) and to the identification of geothermal systems that have no surface expression (blind systems). 3-dimensional geologic modeling is a tool that can elucidate the specific stratigraphic intervals and structural geometries that host geothermal reservoirs. Astor Pass, NV USA lies just beyond the northern extent of the dextral Pyramid Lake fault zone near the boundarymore » between two distinct structural domains, the Walker Lane and the Basin and Range, and exhibits characteristics of each setting. Both northwest-striking, left-stepping dextral faults of the Walker Lane and kinematically linked northerly striking normal faults associated with the Basin and Range are present. Previous studies at Astor Pass identified a blind geothermal system controlled by the intersection of west-northwest and north-northwest striking dextral-normal faults. Wells drilled into the southwestern quadrant of the fault intersection yielded 94°C fluids, with geothermometers suggesting a maximum reservoir temperature of 130°C. A 3-dimensional model was constructed based on detailed geologic maps and cross-sections, 2-dimensional seismic data, and petrologic analysis of the cuttings from three wells in order to further constrain the structural setting. The model reveals the specific geometry of the fault interaction area at a level of detail beyond what geologic maps and cross-sections can provide.« less

Beyond dichotomies: Gender and intersecting inequalities in climate change studies.

PubMed

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.

Wind tunnel measurements of pollutant turbulent fluxes in urban intersections

NASA Astrophysics Data System (ADS)

Carpentieri, Matteo; Hayden, Paul; Robins, Alan G.

2012-01-01

Wind tunnel experiments have been carried out at the EnFlo laboratory to measure mean and turbulent tracer fluxes in geometries of real street canyon intersections. The work was part of the major DAPPLE project, focussing on the area surrounding the intersection between Marylebone Road and Gloucester Place in Central London, UK. Understanding flow and dispersion in urban streets is a very important issue for air quality management and planning, and turbulent mass exchange processes are important phenomena that are very often neglected in urban modelling studies. The adopted methodology involved the combined use of laser Doppler anemometry and tracer concentration measurements. This methodology was applied to quantify the mean and turbulent flow and dispersion fields within several street canyon intersections. Vertical profiles of turbulent tracer flux were also measured. The technique, despite a number of limitations, proved reliable and allowed tracer balance calculations to be undertaken in the selected street canyon intersections. The experience gained in this work will enable much more precise studies in the future as issues affecting the accuracy of the experimental technique have been identified and resolved.

The fully actuated traffic control problem solved by global optimization and complementarity

NASA Astrophysics Data System (ADS)

Ribeiro, Isabel M.; de Lurdes de Oliveira Simões, Maria

2016-02-01

Global optimization and complementarity are used to determine the signal timing for fully actuated traffic control, regarding effective green and red times on each cycle. The average values of these parameters can be used to estimate the control delay of vehicles. In this article, a two-phase queuing system for a signalized intersection is outlined, based on the principle of minimization of the total waiting time for the vehicles. The underlying model results in a linear program with linear complementarity constraints, solved by a sequential complementarity algorithm. Departure rates of vehicles during green and yellow periods were treated as deterministic, while arrival rates of vehicles were assumed to follow a Poisson distribution. Several traffic scenarios were created and solved. The numerical results reveal that it is possible to use global optimization and complementarity over a reasonable number of cycles and determine with efficiency effective green and red times for a signalized intersection.

The development and evaluation of accident predictive models

NASA Astrophysics Data System (ADS)

Maleck, T. L.

1980-12-01

A mathematical model that will predict the incremental change in the dependent variables (accident types) resulting from changes in the independent variables is developed. The end product is a tool for estimating the expected number and type of accidents for a given highway segment. The data segments (accidents) are separated in exclusive groups via a branching process and variance is further reduced using stepwise multiple regression. The standard error of the estimate is calculated for each model. The dependent variables are the frequency, density, and rate of 18 types of accidents among the independent variables are: district, county, highway geometry, land use, type of zone, speed limit, signal code, type of intersection, number of intersection legs, number of turn lanes, left-turn control, all-red interval, average daily traffic, and outlier code. Models for nonintersectional accidents did not fit nor validate as well as models for intersectional accidents.

Multiphase flow in geometrically simple fracture intersections

USGS Publications Warehouse

Basagaoglu, H.; Meakin, P.; Green, C.T.; Mathew, M.; ,

2006-01-01

A two-dimensional lattice Boltzmann (LB) model with fluid-fluid and solid-fluid interaction potentials was used to study gravity-driven flow in geometrically simple fracture intersections. Simulated scenarios included fluid dripping from a fracture aperture, two-phase flow through intersecting fractures and thin-film flow on smooth and undulating solid surfaces. Qualitative comparisons with recently published experimental findings indicate that for these scenarios the LB model captured the underlying physics reasonably well.

Estimation of fuel loss due to idling of vehicles at a signalized intersection in Chennai, India

NASA Astrophysics Data System (ADS)

Vasantha Kumar, S.; Gulati, Himanshu; Arora, Shivam

2017-11-01

The vehicles while waiting at signalized intersections are generally found to be in idling condition, i.e., not switching off their vehicles during red times. This phenomenon of idling of vehicles during red times at signalized intersections may lead to huge economic loss as lot of fuel is consumed by vehicles when they are in idling condition. The situation may even be worse in countries like India as different vehicle types consume varying amount of fuel. Only limited studies have been reported on estimation of fuel loss due to idling of vehicles in India. In the present study, one of the busy intersections in Chennai, namely, Tidel Park Junction in Rajiv Gandhi salai was considered. Data collection was carried out in one approach road of the intersection during morning and evening peak hours on a typical working day by manually noting down the red timings of each cycle and the corresponding number of two-wheelers, three-wheelers, passenger cars, light commercial vehicles (LCV) and heavy motorized vehicles (HMV) that were in idling mode. Using the fuel consumption values of various vehicles types suggested by Central Road Research Institute (CRRI), the total fuel loss during the study period was found to be Rs. 4,93,849/-. The installation of red timers, synchronization of signals, use of non-motorized transport for short trips and public awareness are some of the measures which government need to focus to save the fuel wasted at signalized intersections in major cities of India.

Safety surrogate histograms (SSH): A novel real-time safety assessment of dilemma zone related conflicts at signalized intersections.

PubMed

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. Copyright © 2015 Elsevier Ltd. All rights reserved.

Traffic signal design and simulation for vulnerable road users safety and bus preemption

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lo, Shih-Ching; Huang, Hsieh-Chu

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 publicmore » 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.« less

Safety effects of exclusive and concurrent signal phasing for pedestrian crossing.

PubMed

Zhang, Yaohua; Mamun, Sha A; Ivan, John N; Ravishanker, Nalini; Haque, Khademul

2015-10-01

This paper describes the estimation of pedestrian crash count and vehicle interaction severity prediction models for a sample of signalized intersections in Connecticut with either concurrent or exclusive pedestrian phasing. With concurrent phasing, pedestrians cross at the same time as motor vehicle traffic in the same direction receives a green phase, while with exclusive phasing, pedestrians cross during their own phase when all motor vehicle traffic on all approaches is stopped. Pedestrians crossing at each intersection were observed and classified according to the severity of interactions with motor vehicles. Observation intersections were selected to represent both types of signal phasing while controlling for other physical characteristics. In the nonlinear mixed models for interaction severity, pedestrians crossing on the walk signal at an exclusive signal experienced lower interaction severity compared to those crossing on the green light with concurrent phasing; however, pedestrians crossing on a green light where an exclusive phase was available experienced higher interaction severity. Intersections with concurrent phasing have fewer total pedestrian crashes than those with exclusive phasing but more crashes at higher severity levels. It is recommended that exclusive pedestrian phasing only be used at locations where pedestrians are more likely to comply. Copyright © 2015. Published by Elsevier Ltd.

Management challenges at the intersection of public policy environments and strategic decision making in public hospitals.

PubMed

Longest, Beaufort B

2012-01-01

Hospitals in the United States are heavily impacted by public policies that affect them. For example, Medicare and Medicaid programs account for more than half the revenue in most of the nation's almost 5,000 community hospitals, including the almost 1,100 public hospitals controlled by state and local governments (American Hospital Association, 2012). The public hospitals are especially closely aligned with and controlled by governmental entities compared with hospitals with other kinds of sponsorship. This article addresses the management challenges at the intersection of the strategic management of public hospitals and their public policy environments. Public hospitals are complicated entities designed not only to provide health services but also in many cases to play key roles in health-related research and education and to play important general economic development roles in their communities. The multi-faceted strategic decision making in these organizations is as heavily affected by their public policy environments as by their business, demographic, technological or other external environments. Effectively managing the intersection of their public policy environments and their strategic management is indeed vital for contemporary public hospitals. This article is intended to clarify certain aspects of this intersection through a description and model of the strategic activity in public hospitals and the connection between this activity and their external environments. Specific attention is focused on the concept of public policy environments and their features. Attention is also given to how managers can assess public policy environments and incorporate the results into strategic activities.

Empowered Intersectionality among Black Female K-12 Leaders: A Transcendental Phenomenological Study

ERIC Educational Resources Information Center

McNeal, Carla

2017-01-01

Black female school leaders remain underrepresented as educational leaders in the K-12 context as marginalizing factors persist in the field. The purpose of this transcendental phenomenological study was to explore the lived experiences of Black female school leaders through the lens of intersectionality. For this research study, intersectionality…

Re-Seeing Race in a Post-Obama Age: Asian American Studies, Comparative Ethnic Studies, and Intersectional Pedagogies

ERIC Educational Resources Information Center

Schlund-Vials, Cathy J.

2011-01-01

Focused on comparative ethnic studies and intersectionality, the author commences with a discussion about Barack Obama's historic inauguration and the Asian American literature classroom. This essay argues that courses, programs, and departments focused on ethnicity, race, gender, class, and sexuality remain important precisely because they…

Intersectionality and risk for ischemic heart disease in Sweden: Categorical and anti-categorical approaches.

PubMed

Wemrell, Maria; Mulinari, Shai; Merlo, Juan

2017-03-01

Intersectionality theory can contribute to epidemiology and public health by furthering understanding of power dynamics driving production of health disparities, and increasing knowledge about heterogeneities within, and overlap between, social categories. Drawing on McCall, we relate the first of these potential contributions to categorical intersectionality and the second to anti-categorical intersectionality. Both approaches are used in study of risk of ischemic heart disease (IHD), based on register data on 3.6 million adults residing in Sweden by 2010, followed for three years. Categorical intersectionality is here coupled with between-group differences in average risk calculation, as we use intersectional categorizations while estimating odds ratios through logistic regressions. The anti-categorical approach is operationalized through measurement of discriminatory accuracy (DA), i.e., capacity to accurately categorize individuals with or without a certain outcome, through computation of the area under the curve (AUC). Our results show substantial differences in average risk between intersectional groupings. The DA of social categorizations is found to be low, however, due to outcome variability within and overlap between categories. We argue that measures of DA should be used for proper interpretation of differences in average risk between social (or any other) categories. Tension between average between-group risk and the DA of categorizations, which can be related to categorical and anti-categorical intersectional analyses, should be made explicit and discussed to a larger degree in epidemiology and public health. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Re-entry experiences of Black men living with HIV/AIDS after release from prison: Intersectionality and implications for care.

PubMed

Sun, Shufang; Crooks, Natasha; Kemnitz, Rebecca; Westergaard, Ryan P

2018-06-12

Both the HIV epidemic and incarceration disproportionately affect Black men in the United States. A critical period for incarcerated Black men living with HIV/AIDS is re-entry into the community, which is often associated with adverse health outcomes. Additionally, Black men living with HIV/AIDS involved in the criminal justice system are burdened by multiple, intersecting disadvantaged identities and social positions. This study aimed to examine community re-entry experiences among Black men living with HIV/AIDS from an intersectional perspective. In-depth, semi-structured interviews were conducted with 16 incarcerated Black men in Wisconsin, at pre-release from prison and six months after re-entry. Thematic analysis guided by intersectionality theory was used to analyze interview transcripts. Seven emerged themes included Intersectional Identities and Social Positions, Family Support, Neighborhood Violence, Relationship with Law Enforcement, Employment, Mental Health Concerns, and Medical Care and Medication Management. Intersecting identities and social positions interact with factors at multiple levels to inform health and HIV care. A conceptual framework was developed to illustrate relationships among themes. Findings demonstrate the relevance of intersectionality theory in HIV care with Black men involved in criminal justice system. Incorporating a social-ecological perspective into intersectionality framework could be useful in theoretical and empirical research. Disenfranchised communities may particularly benefit from interventions that address community- and systemic-level issues. Copyright © 2018 Elsevier Ltd. All rights reserved.

Evaluation of Adaptive Signal Control Technology—Volume 2 : Comparison of Base Condition to the First Year After Implementation

DOT National Transportation Integrated Search

2018-05-01

Field evaluation of adaptive signal control technologies (ASCT) is very important in understanding the systems contribution to safety and operational efficiency. Data were collected at six intersections along the Neil Street corridor in Champaign,...

Learning-based traffic signal control algorithms with neighborhood information sharing: An application for sustainable mobility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aziz, H. M. Abdul; Zhu, Feng; Ukkusuri, Satish V.

Here, this research applies R-Markov Average Reward Technique based reinforcement learning (RL) algorithm, namely RMART, for vehicular signal control problem leveraging information sharing among signal controllers in connected vehicle environment. We implemented the algorithm in a network of 18 signalized intersections and compare the performance of RMART with fixed, adaptive, and variants of the RL schemes. Results show significant improvement in system performance for RMART algorithm with information sharing over both traditional fixed signal timing plans and real time adaptive control schemes. Additionally, the comparison with reinforcement learning algorithms including Q learning and SARSA indicate that RMART performs better atmore » higher congestion levels. Further, a multi-reward structure is proposed that dynamically adjusts the reward function with varying congestion states at the intersection. Finally, the results from test networks show significant reduction in emissions (CO, CO 2, NO x, VOC, PM 10) when RL algorithms are implemented compared to fixed signal timings and adaptive schemes.« less

New perspectives on occupational health and safety in immigrant populations: studying the intersection between immigrant background and gender.

PubMed

Mousaid, Sarah; De Moortel, Deborah; Malmusi, Davide; Vanroelen, Christophe

2016-01-01

Few studies investigating health inequalities pay attention to the intersection between several social determinants of health. The purpose of this article is to examine the relation between perceptions of work-related health and safety risk (WHSR) and (1) immigrant background and (2) gender in the EU-15. The effects are controlled for educational attainment, the quality of work (QOW) and occupation. Pooled data from the European Social Survey 2004 and 2010 are used in this study. The sample is restricted to respondents of working age (16-65 years) (N = 17,468). The immigrants are divided into two groups according to their country of origin: (semi-)periphery and core countries. Both groups of immigrants are compared to natives. Additionally, the research population is stratified by gender. Descriptive statistics and logistic regression analyses are used. Core immigrants (both men and women) do not differ from natives in terms of QOW. (Semi-)periphery immigrants (both men and women) are employed in jobs with lower QOW. While no differences in WHSR are found among men, female immigrants (both (semi-)periphery and core) have significantly more WHSR compared to native women. Although WHSR is generally lower in women, (semi-)periphery women have a similar prevalence of WHSR as men. (Semi-)periphery immigrants are employed in lower quality jobs, while core immigrants do not differ from natives in that regard. Female immigrant workers--especially those from (semi-)periphery countries--have higher WHSR compared to native women. Our findings highlight the importance of an intersectional approach in the study of work-related health inequalities.

An intelligent IoT emergency vehicle warning system using RFID and Wi-Fi technologies for emergency medical services.

PubMed

Lai, Yeong-Lin; Chou, Yung-Hua; Chang, Li-Chih

2018-01-01

Collisions between emergency vehicles for emergency medical services (EMS) and public road users have been a serious problem, impacting on the safety of road users, emergency medical technicians (EMTs), and the patients on board. The aim of this study is to develop a novel intelligent emergency vehicle warning system for EMS applications. The intelligent emergency vehicle warning system is developed by Internet of Things (IoT), radio-frequency identification (RFID), and Wi-Fi technologies. The system consists of three major parts: a system trigger tag, an RFID system in an emergency vehicle, and an RFID system at an intersection. The RFID system either in an emergency vehicle or at an intersection contains a controller, an ultrahigh-frequency (UHF) RFID reader module, a Wi-Fi module, and a 2.4-GHz antenna. In addition, a UHF ID antenna is especially designed for the RFID system in an emergency vehicle. The IoT system provides real-time visual warning at an intersection and siren warning from an emergency vehicle in order to effectively inform road users about an emergency vehicle approaching. The developed intelligent IoT emergency vehicle warning system demonstrates the capabilities of real-time visual and siren warnings for EMS safety.

Conical intersection in a bilirubin model A possible pathway for phototherapy of neonatal jaundice

NASA Astrophysics Data System (ADS)

Zietz, Burkhard; Blomgren, Fredrik

2006-03-01

Phototherapy of neonatal jaundice involves Z- E-isomerisation around an exocyclic double bond in bilirubin. Our results of a CASSCF study on dipyrrinone, a bilirubin model, show a conical intersection between the ground and first excited singlet states associated with the Z- E-isomerisation. The conical intersection, located ca. 50 kJ/mol below the Franck-Condon-point, together with the S 1 minimum, ca. 50 kJ/mol below the conical intersection, are able to explain the available time-resolved spectroscopic data (the very short lifetime of the initially excited state and transient 'dark state' intermediate) as well as bilirubin's very low fluorescence quantum yield and the medium-efficient photoisomerisation reaction.

Design, analysis, and testing of a metal matrix composite web/flange intersection

NASA Technical Reports Server (NTRS)

Biggers, S. B.; Knight, N. F., Jr.; Moran, S. G.; Olliffe, R.

1992-01-01

An experimental and analytical program to study the local design details of a typical T-shaped web/flange intersection made from a metal matrix composite is described. Loads creating flange bending were applied to specimens having different designs and boundary conditions. Finite element analyses were conducted on models of the test specimens to predict the structural response. The analyses correctly predict failure load, mode, and location in the fillet material in the intersection region of the web and the flange when specimen quality is good. The test program shows the importance of fabrication quality in the intersection region. The full-scale test program that led to the investigation of this local detail is also described.

Research notes : safety at high-speed intersections.

DOT National Transportation Integrated Search

2010-04-01

A 2010 study for ODOT by researchers at the Oregon State University School of Civil and Construction Engineering titled, Evaluating Safety and Operations of High-Speed Signalized Intersections, examined effective means for improving safety at isolate...

Quad City Intersection Traffic Accident Study: 1993 Data

DOT National Transportation Integrated Search

1996-03-01

Accident information is an important factor from which to work towards the : regional Transportation System Management (TSM) objective of improving the : safety of the local transportation system. The 1993 Quad City Intersection : Traffic Accident Re...

Stepfamilies: The Intersection of Culture, Context, and Biology.

ERIC Educational Resources Information Center

Bray, James

1999-01-01

Discusses five areas concerning Heatherington et al.'s study: nature and nurture issues; deviance versus normative behavior in stepfamilies; context and meaning in different types of families; intersecting developmental trajectories; and gender differences. (JPB)

The impact of transportation infrastructure on bicycling injuries and crashes: a review of the literature

PubMed Central

2009-01-01

Background Bicycling has the potential to improve fitness, diminish obesity, and reduce noise, air pollution, and greenhouse gases associated with travel. However, bicyclists incur a higher risk of injuries requiring hospitalization than motor vehicle occupants. Therefore, understanding ways of making bicycling safer and increasing rates of bicycling are important to improving population health. There is a growing body of research examining transportation infrastructure and the risk of injury to bicyclists. Methods We reviewed studies of the impact of transportation infrastructure on bicyclist safety. The results were tabulated within two categories of infrastructure, namely that at intersections (e.g. roundabouts, traffic lights) or between intersections on "straightaways" (e.g. bike lanes or paths). To assess safety, studies examining the following outcomes were included: injuries; injury severity; and crashes (collisions and/or falls). Results The literature to date on transportation infrastructure and cyclist safety is limited by the incomplete range of facilities studied and difficulties in controlling for exposure to risk. However, evidence from the 23 papers reviewed (eight that examined intersections and 15 that examined straightaways) suggests that infrastructure influences injury and crash risk. Intersection studies focused mainly on roundabouts. They found that multi-lane roundabouts can significantly increase risk to bicyclists unless a separated cycle track is included in the design. Studies of straightaways grouped facilities into few categories, such that facilities with potentially different risks may have been classified within a single category. Results to date suggest that sidewalks and multi-use trails pose the highest risk, major roads are more hazardous than minor roads, and the presence of bicycle facilities (e.g. on-road bike routes, on-road marked bike lanes, and off-road bike paths) was associated with the lowest risk. Conclusion Evidence is beginning to accumulate that purpose-built bicycle-specific facilities reduce crashes and injuries among cyclists, providing the basis for initial transportation engineering guidelines for cyclist safety. Street lighting, paved surfaces, and low-angled grades are additional factors that appear to improve cyclist safety. Future research examining a greater variety of infrastructure would allow development of more detailed guidelines. PMID:19845962

Effects of countdown timers on driver behavior after the yellow onset at Chinese intersections.

PubMed

Long, Kejun; Han, Lee D; Yang, Qiang

2011-10-01

Few studies have focused on the effect of countdown timers at signalized intersections in China, where such timers are widely deployed for their perceived benefits of increased safety and capacity. This study examines the effect of countdown timers on driver behavior during the yellow interval. Signal phasing and traffic operations were videotaped at 4 comparable signalized intersections under normal conditions. Microscopic details were extracted manually at 25 Hz to yield 24 h of data on onset time of the yellow, onset time of the red, driver location and actions after the onset of the yellow, red light-running violations, etc. For comparable intersections with and without countdown timers, driver behavior measured by driver decision (stop or go) and vehicle entry time (when the vehicle crosses the stop line) were analyzed using binary logistical regression (BLR) and a nonparametric test, respectively. The results suggest that countdown timers can indeed influence driver behaviors, in terms of decisions to stop or cross the intersection as well as the distribution of vehicle entry times. There was a strong correlation between the presence of countdown timers and an increase in red light violations. Countdown timers may lead to increased entrance into the intersection during the later portions of the yellow and even the red. This alarming finding calls for further research as well as for serious consideration before the field deployment of countdown timers.

How Student Teachers (Don't) Talk about Race: An Intersectional Analysis

ERIC Educational Resources Information Center

Young, Kathryn S.

2016-01-01

This study explores how student teacher talk about their students illuminates the identities ascribed to these same students. It uses a hybrid intersectional framework based on Disability Studies, Critical Race Theory, and Latino Critical Theory and methodologies (like examining majoritarian stories, counter-storytelling, coded talk, and…

"Two Totally Different People": Dissonance of Intersecting Identities in White College Women

ERIC Educational Resources Information Center

Dalpra, Abby; Vianden, Jörg

2017-01-01

This phenomenological study explored the intersecting privileged (racial) and oppressed (gender) identities of eight White college women. Through three interviews, this study aimed to understand how the participants experience socially conflicting identities. Findings indicated that the participants felt more connected to their gender than their…

Cooperative Intersection Collision Avoidance System - Stop Sign Assist : experiments to validate use of an in-vehicle interface design.

DOT National Transportation Integrated Search

2012-04-01

The three studies included in the current report examine the transition from an infrastructure-based rural : intersection crossing assist system to one located inside a vehicle. The primary goals of the first study, conducted in : a simulator, were t...

Evolving norms at the intersection of health and trade.

PubMed

Drope, Jeffrey; Lencucha, Raphael

2014-06-01

There has been growing tension at the intersection of health and economic policy making as global governance has increased across sectors. This tension has been particularly evident between tobacco control and trade policy, as the international norms that frame them -- particularly the Framework Convention on Tobacco Control and the World Trade Organization (WTO) -- have continued to institutionalize. Using five case studies of major tobacco-related trade disputes from the principal multilateral system of trade governance -- the WTO/General Agreement on Tariffs and Trade -- we trace the evolution of these interacting norms over nearly twenty-five years. Our analytic framework focuses on the actors that advance, defend, and challenge these norms. We find that an increasingly broad network, which includes governments, intergovernmental organizations, nongovernmental organizations, and members of the epistemic community, is playing a more active role in seeking to resolve these tensions. Moreover, key economic actors are beginning to incorporate health more actively into their messaging and activities. We also demonstrate that the most recent resonant messages reflect a more nuanced integration of the two norms. The tobacco control example has direct relevance to related policy areas, including environment, safety, access to medicines, diet, and alcohol. Copyright © 2014 by Duke University Press.

Traffic signal synchronization in the saturated high-density grid road network.

PubMed

Hu, Xiaojian; Lu, Jian; Wang, Wei; Zhirui, Ye

2015-01-01

Most existing traffic signal synchronization strategies do not perform well in the saturated high-density grid road network (HGRN). Traffic congestion often occurs in the saturated HGRN, and the mobility of the network is difficult to restore. In order to alleviate traffic congestion and to improve traffic efficiency in the network, the study proposes a regional traffic signal synchronization strategy, named the long green and long red (LGLR) traffic signal synchronization strategy. The essence of the strategy is to control the formation and dissipation of queues and to maximize the efficiency of traffic flows at signalized intersections in the saturated HGRN. With this strategy, the same signal control timing plan is used at all signalized intersections in the HGRN, and the straight phase of the control timing plan has a long green time and a long red time. Therefore, continuous traffic flows can be maintained when vehicles travel, and traffic congestion can be alleviated when vehicles stop. Using the strategy, the LGLR traffic signal synchronization model is developed, with the objective of minimizing the number of stops. Finally, the simulation is executed to analyze the performance of the model by comparing it to other models, and the superiority of the LGLR model is evident in terms of delay, number of stops, queue length, and overall performance in the saturated HGRN.

Development of minimum standards for event-based data collection loggers and performance measure definitions for signalized intersections [summary].

DOT National Transportation Integrated Search

2017-01-01

New traffic signal controllers, which have advanced data collection abilities, offer better information about the response of traffic signal timings to traffic flows. However, traffic engineers need more than raw data. The controllers must be set up ...

U-Turns at signalized intersections.

DOT National Transportation Integrated Search

2004-06-01

The objectives of the study were to examine the safety consequences from the installation of U-turns at signalized intersections in Kentucky and to develop a set of guidelines for using this alternative in the future. The literature review indicated ...

Intersection negotiation problems of older drivers. Volume 1

DOT National Transportation Integrated Search

1998-09-01

This project included a background literature synthesis and observational field study. The research goals were to document driving problems and errors at intersections, for older drivers using their own cars to travel familiar and unfamiliar routes, ...

[When and where motorcyclists have accidents and die in Belo Horizonte, Minas Gerais State, Brazil].

PubMed

Diniz, Eugênio Paceli Hatem; Pinheiro, Letícia Cavalari; Proietti, Fernando Augusto

2015-12-01

The objective of this study was to analyze traffic accidents involving motorcycles in Belo Horizonte, Minas Gerais State, Brazil, from 2007 to 2011 and to identify clusters of high-risk and hazardous intersections in and around the city. Data were provided by the Military Police Brigade and the Emergency Medical Service (SAMU). Accident severity rates were used to identify critical intersections. Two techniques were used: kernel analysis and scan statistics (continuous Poisson model). High-risk clusters were located in the downtown area and on major thoroughfares. Surprisingly, the highest risk of accidents and death occurred not at intersections, but between them. Hazardous intersections are part of routes used to access regions around Greater Metropolitan Belo Horizonte. Two distinct trends in mortality rates and accidents were identified. Most motorcycle deaths occurred after 7:00 PM. The study concludes that there is an urgent need to improve motorcycle and public transportation routes.

Estimating rear-end accident probabilities at signalized intersections: a comparison study of intersections with and without green signal countdown devices.

PubMed

Ni, Ying; Li, Keping

2014-01-01

Rear-end accidents are the most common accident type at signalized intersections, because the diversity of actions taken increases due to signal change. Green signal countdown devices (GSCDs), which have been widely installed in Asia, are thought to have the potential of improving capacity and reducing accidents, but some negative effects on intersection safety have been observed in practice; for example, an increase in rear-end accidents. A microscopic modeling approach was applied to estimate rear-end accident probability during the phase transition interval in the study. The rear-end accident probability is determined by the following probabilities: (1) a leading vehicle makes a "stop" decision, which was formulated by using a binary logistic model, and (2) the following vehicle fails to stop in the available stopping distance, which is closely related to the critical deceleration used by the leading vehicle. Based on the field observation carried out at 2 GSCD intersections and 2 NGSCD intersections (i.e., intersections without GSCD devices) along an arterial in Suzhou, the rear-end probabilities at GSCD and NGSCD intersections were calculated using Monte Carlo simulation. The results suggested that, on the one hand, GSCDs caused significantly negative safety effects during the flashing green interval, especially for vehicles in a zone ranging from 15 to 70 m; on the other hand, GSCD devices were helpful in reducing rear-end accidents during the yellow interval, especially in a zone from 0 to 50 m. GSCDs helped shorten indecision zones and reduce rear-end collisions near the stop line during the yellow interval, but they easily resulted in risky car following behavior and much higher rear-end collision probabilities at indecision zones during both flashing green and yellow intervals. GSCDs are recommended to be cautiously installed and education on safe driving behavior should be available.

"It's an Uphill Battle Everyday": Intersectionality, Low-Income Black Heterosexual Men, and Implications for HIV Prevention Research and Interventions.

PubMed

Bowleg, Lisa; Teti, Michelle; Malebranche, David J; Tschann, Jeanne M

2013-01-01

This interview study, the initial qualitative phase of a larger mixed methods HIV prevention study focused on Black heterosexual men, used intersectionality as a theoretical framework to explore: (1) How a sample of Black heterosexual men describe and experience the multiple intersections of race, gender, and SES; and (2) How these descriptions reflected interlocking systems of social inequality for Black men at the social-structural level. Participants were 30 predominantly low-income self-identified Black heterosexual men between the ages of 18 and 44. Analyses highlighted four themes that demonstrate how participants' individual-level experiences as Black men reflect macro social-structural inequality: (1) racial discrimination and microaggressions; (2) unemployment; (3) incarceration; and (4) police surveillance and harassment. We discuss the study's findings within the context of social-structural factors that disproportionately and adversely impact Black men. We also highlight the implications of the intersectionality perspective for HIV prevention research and interventions for Black heterosexual men.

Impact of eliminating fracture intersection nodes in multiphase compositional flow simulation

NASA Astrophysics Data System (ADS)

Walton, Kenneth M.; Unger, Andre J. A.; Ioannidis, Marios A.; Parker, Beth L.

2017-04-01

Algebraic elimination of nodes at discrete fracture intersections via the star-delta technique has proven to be a valuable tool for making multiphase numerical simulations more tractable and efficient. This study examines the assumptions of the star-delta technique and exposes its effects in a 3-D, multiphase context for advective and dispersive/diffusive fluxes. Key issues of relative permeability-saturation-capillary pressure (kr-S-Pc) and capillary barriers at fracture-fracture intersections are discussed. This study uses a multiphase compositional, finite difference numerical model in discrete fracture network (DFN) and discrete fracture-matrix (DFM) modes. It verifies that the numerical model replicates analytical solutions and performs adequately in convergence exercises (conservative and decaying tracer, one and two-phase flow, DFM and DFN domains). The study culminates in simulations of a two-phase laboratory experiment in which a fluid invades a simple fracture intersection. The experiment and simulations evoke different invading fluid flow paths by varying fracture apertures as oil invades water-filled fractures and as water invades air-filled fractures. Results indicate that the node elimination technique as implemented in numerical model correctly reproduces the long-term flow path of the invading fluid, but that short-term temporal effects of the capillary traps and barriers arising from the intersection node are lost.

A Phenomenological Study on the Leadership Development of African American Women Executives in Academia and Business

ERIC Educational Resources Information Center

Davis, Deanna Rachelle

2012-01-01

The purpose of this qualitative phenomenological study was to explore the intersectionality of race and gender for African American women through their lived experiences of how they developed into leaders. This research study was designed to determine how the intersection of race and gender identities contributed to the elements of leadership…

Analysis of Driver Evasive Maneuvering Prior to Intersection Crashes Using Event Data Recorders.

PubMed

Scanlon, John M; Kusano, Kristofer D; Gabler, Hampton C

2015-01-01

Intersection crashes account for over 4,500 fatalities in the United States each year. Intersection Advanced Driver Assistance Systems (I-ADAS) are emerging vehicle-based active safety systems that have the potential to help drivers safely navigate across intersections and prevent intersection crashes and injuries. The performance of an I-ADAS is expected to be highly dependent upon driver evasive maneuvering prior to an intersection crash. Little has been published, however, on the detailed evasive kinematics followed by drivers prior to real-world intersection crashes. The objective of this study was to characterize the frequency, timing, and kinematics of driver evasive maneuvers prior to intersection crashes. Event data recorders (EDRs) downloaded from vehicles involved in intersection crashes were investigated as part of NASS-CDS years 2001 to 2013. A total of 135 EDRs with precrash vehicle speed and braking application were downloaded to investigate evasive braking. A smaller subset of 59 EDRs that collected vehicle yaw rate was additionally analyzed to investigate evasive steering. Each vehicle was assigned to one of 3 precrash movement classifiers (traveling through the intersection, completely stopped, or rolling stop) based on the vehicle's calculated acceleration and observed velocity profile. To ensure that any significant steering input observed was an attempted evasive maneuver, the analysis excluded vehicles at intersections that were turning, driving on a curved road, or performing a lane change. Braking application at the last EDR-recorded time point was assumed to indicate evasive braking. A vehicle yaw rate greater than 4° per second was assumed to indicate an evasive steering maneuver. Drivers executed crash avoidance maneuvers in four-fifths of intersection crashes. A more detailed analysis of evasive braking frequency by precrash maneuver revealed that drivers performing complete or rolling stops (61.3%) braked less often than drivers traveling through the intersection without yielding (79.0%). After accounting for uncertainty in the timing of braking and steering data, the median evasive braking time was found to be between 0.5 to 1.5 s prior to impact, and the median initial evasive steering time was found to occur between 0.5 and 0.9 s prior to impact. The median average evasive braking deceleration for all cases was found to be 0.58 g. The median of the maximum evasive vehicle yaw rates was found to be 8.2° per second. Evasive steering direction was found to be most frequently in the direction of travel of the approaching vehicle. The majority of drivers involved in intersection crashes were alert enough to perform an evasive action. Most drivers used a combination of steering and braking to avoid a crash. The average driver attempted to steer and brake at approximately the same time prior to the crash.

Determining of the Parking Manoeuvre and the Taxi Blockage Adjustment Factor for the Saturation Flow Rate at the Outlet Legs of Signalized Intersections: Case Study from Rasht City (Iran)

NASA Astrophysics Data System (ADS)

Behbahani, Hamid; Jahangir Samet, Mehdi; Najafi Moghaddam Gilani, Vahid; Amini, Amir

2017-10-01

The presence of taxi stops within the area of signalized intersections at the outlet legs due to unnatural behaviour of the taxis, sudden change of lanes, parking manoeuvres activities and stopping the vehicle to discharge or pick up the passengers have led to reduction of saturation flow rate at the outlet leg of signalized intersections and increased delay as well as affecting the performance of a crossing lane. So far, in term of evaluating effective adjustment factors on saturation flow rate at the inlet legs of the signalized intersections, various studies have been carried out, however; there has not been any studies on effective adjustment factors on saturation flow rate at the inlet legs. Hence, the evaluating of the traffic effects of unique behaviours on the saturation flow rate of the outlet leg is very important. In this research the parking manoeuvre time and taxi blockage time were evaluated and analyzed based on the available lane width as well as determining the effective adjustment factors on the saturation flow rate using recording related data at four signalized intersections in Rasht city. The results show that the average parking manoeuvre time is a function of the lane width and is increased as the lane width is reduced. Also, it is suggested to use the values of 7.37 and 11.31 seconds, respectively for the average parking manoeuvre time and the average blockage time of taxies at the outlet legs of signalized intersections for the traffic designing in Rasht city.

Computational Geometry and Computer-Aided Design

NASA Technical Reports Server (NTRS)

Fay, T. H. (Compiler); Shoosmith, J. N. (Compiler)

1985-01-01

Extended abstracts of papers addressing the analysis, representation, and synthesis of shape information are presented. Curves and shape control, grid generation and contouring, solid modelling, surfaces, and curve intersection are specifically addressed.

Analysis on influencing factors and decision-making of pedestrian crossing at intersections

NASA Astrophysics Data System (ADS)

Liu, Likun; Wang, Ziyang

2017-10-01

The city signal intersection always has complex traffic flow and many traffic accidents. As vulnerable participants, the proportion of traffic accidents involving pedestrians remain high. And a lot of insecure crossing behavior seriously reduce the safety of the intersection. Therefore, it is necessary to carry out in-depth study on the traversing characteristics of pedestrians, reveal the inherent laws of pedestrian crossing, and then put forward targeted measures to improve pedestrian traffic environment, protect pedestrian crossing safety and improve traffic efficiency.

Matrix Models and A Proof of the Open Analog of Witten's Conjecture

NASA Astrophysics Data System (ADS)

Buryak, Alexandr; Tessler, Ran J.

2017-08-01

In a recent work, R. Pandharipande, J. P. Solomon and the second author have initiated a study of the intersection theory on the moduli space of Riemann surfaces with boundary. They conjectured that the generating series of the intersection numbers satisfies the open KdV equations. In this paper we prove this conjecture. Our proof goes through a matrix model and is based on a Kontsevich type combinatorial formula for the intersection numbers that was found by the second author.

Intersectional health-related stigma in persons living with HIV and chronic pain: implications for depressive symptoms.

PubMed

Goodin, Burel R; Owens, Michael A; White, Dyan M; Strath, Larissa J; Gonzalez, Cesar; Rainey, Rachael L; Okunbor, Jennifer I; Heath, Sonya L; Turan, Janet M; Merlin, Jessica S

2018-05-30

"Intersectional health-related stigma" (IHRS) refers to stigma that arises at the convergence of multiple health conditions. People living with HIV (PLWH) and chronic pain have two highly stigmatized health conditions, and thus may be at especially high risk for internalizing these stigmas and consequently experiencing depression. This study examined the intersectionality of internalized HIV and chronic pain stigma in relation to depressive symptoms in a sample of PLWH and chronic pain. Sixty participants were recruited from an HIV clinic in the Southeastern United States. Chronic pain was defined as pain that has been present for at least three consecutive months, and that has been an ongoing problem for at least half the days in the past six months. All participants completed the HIV Stigma Mechanisms Scale, Internalized Stigma in Chronic Pain Scale, the Short-Form Brief Pain Inventory, and the Center for Epidemiological Studies - Depression Scale. Clinical data was collected from medical records. An intersectional HIV and chronic pain composite variable was created and participants were categorized as either high (28%), moderate (32%), or low (40%). Results revealed that intersectional HIV and chronic pain stigma was significantly associated with severity of depressive symptoms (p = .023). Pairwise contrasts revealed that participants with high (p = .009) and moderate (p = .033) intersectional stigma reported significantly greater mean depressive symptom severity than those with low intersectional stigma. Participants who reported the highest levels of internalized HIV and chronic pain stigma also reported the greatest severity of depressive symptoms. This suggests that the experience of both HIV and chronic pain stigma (i.e., IHRS) among PLWH and chronic pain may synergistically perpetuate negative mood in a more profound manner than experiencing either one stigma alone.

Influential factors of red-light running at signalized intersection and prediction using a rare events logistic regression model.

PubMed

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. Copyright © 2016 Elsevier Ltd. All rights reserved.

Differences in passenger car and large truck involved crash frequencies at urban signalized intersections: an exploratory analysis.

PubMed

Dong, Chunjiao; Clarke, David B; Richards, Stephen H; Huang, Baoshan

2014-01-01

The influence of intersection features on safety has been examined extensively because intersections experience a relatively large proportion of motor vehicle conflicts and crashes. Although there are distinct differences between passenger cars and large trucks-size, operating characteristics, dimensions, and weight-modeling crash counts across vehicle types is rarely addressed. This paper develops and presents a multivariate regression model of crash frequencies by collision vehicle type using crash data for urban signalized intersections in Tennessee. In addition, the performance of univariate Poisson-lognormal (UVPLN), multivariate Poisson (MVP), and multivariate Poisson-lognormal (MVPLN) regression models in establishing the relationship between crashes, traffic factors, and geometric design of roadway intersections is investigated. Bayesian methods are used to estimate the unknown parameters of these models. The evaluation results suggest that the MVPLN model possesses most of the desirable statistical properties in developing the relationships. Compared to the UVPLN and MVP models, the MVPLN model better identifies significant factors and predicts crash frequencies. The findings suggest that traffic volume, truck percentage, lighting condition, and intersection angle significantly affect intersection safety. Important differences in car, car-truck, and truck crash frequencies with respect to various risk factors were found to exist between models. The paper provides some new or more comprehensive observations that have not been covered in previous studies. Copyright © 2013 Elsevier Ltd. All rights reserved.

Integrating intersection traffic signal data into a traffic monitoring program.

DOT National Transportation Integrated Search

2014-09-01

The objective of this study was to provide the Georgia Department of Transportation with : an evaluation of the feasibility of integrating intersection traffic signal data into a traffic : monitoring program. Some of the pertinent conclusions from th...

Statistical Models of At-Grade Intersection Accidents. Addendum.

DOT National Transportation Integrated Search

2000-03-01

This report is an addendum to the work published in FHWA-RD-96-125 titled Statistical Models of At-Grade Intersection Accidents. The objective of both research studies was to develop statistical models of the relationship between traffic accide...

Evaluation of bike boxes at signalized intersections.

DOT National Transportation Integrated Search

2011-01-01

This report presents a before-after study of bike boxes at 10 signalized intersections in Portland, Oregon. The bike boxes, also known as advanced stop lines or advanced stop boxes, were installed to increase visibility of cyclists and reduce conflic...

Street Intersection Characteristics and Their Impacts on Perceived Bicycling Safety

DOT National Transportation Integrated Search

2018-01-01

Safety concern is one of the core issues that deter people from bicycling in the US. Earlier studies have explored the associations between intersection design characteristics and bicyclist safety perceptions. Research shows that there are significan...

Safety evaluation of intersection conflict warning system.

DOT National Transportation Integrated Search

2016-06-01

FHWA organized a pooled fund study of 40 States to evaluate low-cost safety strategies as part of its strategic highway safety effort. One of the strategies selected for evaluation was intersection conflict warning systems (ICWSs). This strategy is i...

Impact of Microorganisms on the Dynamics of Unsaturated Flow Within Fractures

NASA Astrophysics Data System (ADS)

Stoner, D. L.; Stedtfeld, R. D.; Tyler, T. L.; White, F. J.; McJunkin, T. R.

2002-12-01

Understanding the impact of microorganisms on fluid flow in groundwater and subsurface environments is of significance because of the importance of natural water resources, contaminant transport, and in situ bioprocesses such as mineral dissolution and recovery, enhanced oil recovery, and remediation. In this study, the impact of microorganisms and nutrient amendments on the behavior of water within a fracture system was evaluated using an experimental system comprised of limestone blocks and a groundwater isolate, {\\ it Sphingomonas} sp. Four blocks (25 cm x 6.6 cm x 5 cm) were configured to make a vertical fracture (50.2 x 5 x 0.07 cm) that was intersected by a horizontal fracture (13.4 x 5 x 0.1 cm). To monitor the behavior of water within the fracture, 5 optical sensors each consisting of a light emitting diode and photocell were installed external to the vertical fracture. Two were installed above the fracture intersection, two below and one at the intersection. The presence of fluid in the fracture was detected as a decrease in light transmission as the fluid passed by each detector. Drop interval (the period of time between succeeding drops at the same detector) and drop width (the period of time it took for a water drop or stream to pass by each detector) data were collected for each of the five detectors. Liquids were introduced via a single needle at the top of the fracture at a rate of 0.5 ml/min. Deionized water, which had been chemically equilibrated with the limestone rock, was the control medium to which 1) cells; 2) cells with 0.01% yeast extract; 3) cells with 0.1% yeast extract; and 4) cells with 0.1% yeast extract and 30 mM urea were added. For the equilibrated water, drop intervals and drop widths above the fracture intersection were ~1 s and <0.1 s, respectively. Drop intervals and drop widths at and below the intersection were ~100 s and ~10 s, respectively. Above the fracture intersection, the addition of cells or cells with 0.01% yeast extract had little effect on drop intervals and drop widths. At and below the intersection, however, drop intervals increased to ~500 s and drop widths to ~10 s. Later with the addition of 0.1% yeast extract or 0.1% yeast extract with urea, drop interval and drop width immediately increased at locations above the fracture intersection and within 24 hours, continuous streaming was observed. For the lower sensors, drop interval and drop width initially decreased, followed by continuous streaming the day after the 0.1% yeast extract and urea was added to the system. In conclusion, the dynamics of drop behavior in fracture systems is a complex process that is impacted by the presence of bacteria and nutrient amendments as well as the fracture configuration.

Modeling Driver Behavior near Intersections in Hidden Markov Model

PubMed Central

Li, Juan; He, Qinglian; Zhou, Hang; Guan, Yunlin; Dai, Wei

2016-01-01

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. PMID:28009838

The Intersectionality of Stigmas among Key Populations of Older Adults Affected by HIV: a Thematic Analysis.

PubMed

Johnson Shen, Megan; Freeman, Ryann; Karpiak, Stephen; Brennan-Ing, Mark; Seidel, Liz; Siegler, Eugenia L

2018-03-26

The present study examined the intersectionality of stigma across varying groups of older persons living with HIV (PWH). Four focus groups of older PWH (gay/bisexual men, heterosexual men, heterosexual and bisexualwomen, and Spanish-speaking) were audio-recorded and transcribed. Inductive thematic text analysis was used to identify qualitative themes. Five major themes emerged from the data: 1) disclosure of HIV status; 2) types of stigma experienced; 3) discrimination experienced; 4) other outcomes associated with experiencing stigma; and 5) influence of aging on social isolation experienced due to stigma. Findings indicate women did not suffer from the intersection of stigmas. Other groups suffered from the intersection of stigma due to HIV status and age (gay/bisexual males); HIV status and perceived stigma of sexual orientation or drug use (heterosexual males); and HIV status and culture/ethnicity (Spanish-speaking). Results indicate that many at-risk groups, including heterosexual men, homosexual men, and Spanish-speaking individuals, experience an intersection of stigma between aging and their sexuality, HIV status, or real or perceived drug use. Results highlight the need for HIV support, especially social support, to address intersection of stigmas for unique groups of individuals disproportionately affected by HIV.

The Safety of Older Pedestrians at Signal-Controlled Crossings.

ERIC Educational Resources Information Center

Harrell, W. Andrew

1996-01-01

Observes the extent to which pedestrians checked for oncoming traffic before crossing signal-controlled intersections on busy city streets. Pedestrians over the age of 50 were the most cautious, especially under dangerous traffic conditions. Older pedestrians were least likely to use other pedestrians as "guides" to safety, instead…

Continuation of the interoperable coordinated signal system deployment in White Plains, New York.

DOT National Transportation Integrated Search

2015-12-01

The City of White Plains, NY owns and operates an advanced traffic control system (TCS) that monitors : and controls over 130 intersections in real time. Its Traffic Department facility is not staffed 24 hours a : day, 7 days a week, but two other ce...

Pedestrian Choice Behavior at Shopping Mall Intersections in China and the United States

ERIC Educational Resources Information Center

Bitgood, Stephen; Davey, Gareth; Huang, Xiaoyi; Fung, Holly

2013-01-01

Pedestrian navigation through public spaces reflects the nature of interaction between behavior and environment. This study compared pedestrian choice behavior at shopping mall intersections in China and the United States. The study found that in both countries (a) pedestrians chose movement patterns that involved the fewest steps and (b) there…

The odd couple: using biomedical and intersectional approaches to address health inequities

PubMed Central

Hankivsky, Olena; Doyal, Lesley; Einstein, Gillian; Kelly, Ursula; Shim, Janet; Weber, Lynn; Repta, Robin

2017-01-01

ABSTRACT Background: Better understanding and addressing health inequities is a growing global priority. Objective: In this paper, we contribute to the literature examining complex relationships between biological and social dimensions in the field of health inequalities. Specifically, we explore the potential of intersectionality to advance current approaches to socio-biological entwinements. Design: We provide a brief overview of current approaches to combining both biological and social factors in a single study, and then investigate the contributions of an intersectional framework to such work. Results: We offer a number of concrete examples of how intersectionality has been used empirically to bring both biological and social factors together in the areas of HIV, post-traumatic stress disorder, female genital circumcision/mutilation/cutting, and cardiovascular disease. Conclusion: We argue that an intersectional approach can further research that integrates biological and social aspects of human lives and human health and ultimately generate better and more precise evidence for effective policies and practices aimed at tackling health inequities. PMID:28641056

The odd couple: using biomedical and intersectional approaches to address health inequities.

PubMed

Hankivsky, Olena; Doyal, Lesley; Einstein, Gillian; Kelly, Ursula; Shim, Janet; Weber, Lynn; Repta, Robin

Better understanding and addressing health inequities is a growing global priority. In this paper, we contribute to the literature examining complex relationships between biological and social dimensions in the field of health inequalities. Specifically, we explore the potential of intersectionality to advance current approaches to socio-biological entwinements. We provide a brief overview of current approaches to combining both biological and social factors in a single study, and then investigate the contributions of an intersectional framework to such work. We offer a number of concrete examples of how intersectionality has been used empirically to bring both biological and social factors together in the areas of HIV, post-traumatic stress disorder, female genital circumcision/mutilation/cutting, and cardiovascular disease. We argue that an intersectional approach can further research that integrates biological and social aspects of human lives and human health and ultimately generate better and more precise evidence for effective policies and practices aimed at tackling health inequities.

Driver attitudes and behaviors at intersections and potential effectiveness of engineering countermeasures

DOT National Transportation Integrated Search

2005-11-01

The objective of this focus group study was to identify driver attitudes and behaviors related to intersection safety and to assess the likely impacts of new or existing infrastructure-based technologies/countermeasures. Four focus groups were conduc...

Implementation of a real-time intersection accident detection system (Phase 1).

DOT National Transportation Integrated Search

2004-10-01

The focus of this research is the feasibility study for the implementation of a real-time accident : detection system at intersections. After reviewing accident detection algorithms investigated in the prior : phase of the research, we explored schem...

Low-cost safety measures at signalized intersections.

DOT National Transportation Integrated Search

2008-05-01

The objectives of this study were to: a) identify intersections with a high number of crashes involving a driver disregarding the traffic signal, b) identify types of low-cost safety measures which may be used as a countermeasure for red light runnin...

The Intersectionality of African American Mothers in Counselor Education: A Phenomenological Examination

ERIC Educational Resources Information Center

Haskins, Natoya H.; Ziomek-Daigle, Jolie; Sewell, Cheryl; Crumb, Lonika; Appling, Brandee; Trepal, Heather

2016-01-01

Using phenomenological inquiry, this study explored the lived experiences and intersecting identities of 8 African American counselor educators who are mothers. Six themes were identified: race, professional strain, work-life balance, support, internalized success, and mothering pedagogy.

Development of data measurement techniques for traffic operations analysis at intersections

DOT National Transportation Integrated Search

1985-06-01

This study was undertaken for the purpose of developing intersection data collection methods and approaches which reflect the current needs of engineers and the state-of-the-art capabilities of available equipment. A literature review summarizes perv...

Driver attitudes and behaviors at intersections and potential effectiveness of engineering countermeasures

DOT National Transportation Integrated Search

2006-03-01

This document is an executive summary of the report "Driver attitudes and behaviors at intersections and potential effectiveness of engineering countermeasures", FHWA-HRT-05-078. The objective of the focus group study was to identify driver attitudes...

Abnormal motor patterns in the framework of the equilibrium-point hypothesis: a cause for dystonic movements?

PubMed

Latash, M L; Gutman, S R

1994-01-01

Until now, the equilibrium-point hypothesis (lambda model) of motor control has assumed nonintersecting force-length characteristics of the tonic stretch reflex for individual muscles. Limited data from animal experiments suggest, however, that such intersections may occur. We have assumed the possibility of intersection of the characteristics of the tonic stretch reflex and performed a computer simulation of movement trajectories and electromyographic patterns. The simulation has demonstrated, in particular, that a transient change in the slope of the characteristic of an agonist muscle may lead to temporary movement reversals, hesitations, oscillations, and multiple electromyographic bursts that are typical of movements of patients with dystonia. The movement patterns of three patients with idiopathic dystonia during attempts at fast single-joint movements (in the elbow, wrist, and ankle) were recorded and compared with the results of the computer simulation. This approach considers that motor disorders in dystonia result from faulty control patterns that may not correlate with any morphological or neurophysiological changes. It provides a basis for the high variability of dystonic movements. The uniqueness of abnormal motor patterns in dystonia, that precludes statistical analysis across patients, may result from subtle differences in the patterns of intersecting characteristics of the tonic stretch reflex. The applicability of our analysis to disordered multijoint movement patterns is discussed.

Tool time: Gender and students' use of tools, control, and authority

NASA Astrophysics Data System (ADS)

Jones, M. Gail; Brader-Araje, Laura; Carboni, Lisa Wilson; Carter, Glenda; Rua, Melissa J.; Banilower, Eric; Hatch, Holly

2000-10-01

In this study, we examined how students used science equipment and tools in constructing knowledge during science instruction. Within a geographical metaphor, we focused on how students use tools when constructing new knowledge, how control of tools is actualized from pedagogical perspectives, how language and tool accessibility intersect, how gender intersects with tool use, and how competition for resources impacts access to tools. Sixteen targeted students from five elementary science classes were observed for 3 days of instruction. Results showed gender differences in students' use of exclusive language and commands, as well as in the ways students played and tinkered with tools. Girls tended to carefully follow the teacher's directions during the laboratory and did little playing or tinkering with science tools. Male students tended to use tools in inventive and exploratory ways. Results also showed that whether or not a student had access to his or her own materials became indicative of the type of verbal interactions that took place during the science investigation. Gender-related patterns in how tools are shared, how dyads relate to the materials and each other, and how materials are used to build knowledge are described.

SOUTHWEST FACADE AS SEEN FROM FLIGHTLINE, VIEW FACING NORTHEAST ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

SOUTHWEST FACADE AS SEEN FROM FLIGHTLINE, VIEW FACING NORTHEAST - Naval Air Station Barbers Point, Control Tower & Aviation Operations Building, Near intersection of runways between Hangar 110 & Building 115, Ewa, Honolulu County, HI

Field Evaluation of Detection-Control System

DOT National Transportation Integrated Search

2014-10-01

High-speed signalized intersections present unique challenges to improving highway safety. Techniques for achieving safety often have an adverse effect on efficiency, and techniques for achieving efficiency sometimes have an adverse effect on safety....

Waiting endurance time estimation of electric two-wheelers at signalized intersections.

PubMed

Huan, Mei; Yang, Xiao-bao

2014-01-01

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.

Traffic signal phasing at intersections to improve safety for alcohol-affected pedestrians.

PubMed

Lenné, Michael G; Corben, Bruce F; Stephan, Karen

2007-07-01

Alcohol-affected pedestrians are among the highest-risk groups involved in pedestrian casualty crashes. This paper investigates the opportunities to use a modified form of traffic signal operation during high-risk periods and at high-risk locations to reduce alcohol-affected pedestrian crashes and the severity of injuries that might otherwise occur. The 'Dwell-on-Red' treatment involves displaying a red traffic signal to all vehicle directions during periods when no vehicular traffic is detected, so that drivers approach high-risk intersections at a lower speed than if a green signal were displayed. Vehicle speed data were collected before and after treatment activation at both a control and treatment site. Speed data were collected both 30 m prior to and at the intersection stop line. The treatment was associated with a reduction in mean vehicle speeds of 3.9 kph (9%) and 11.0 kph (28%) at 30 m and stop line collection points, respectively, and substantial reductions in the proportion of vehicles travelling at threatening speeds with regard to the severity of pedestrian injury. Other important road safety concerns may also benefit from this form of traffic signal modification, and it is recommended that other areas of application be explored, including the other severe trauma categories typically concentrated around signalised intersections.

Waiting Endurance Time Estimation of Electric Two-Wheelers at Signalized Intersections

PubMed Central

Huan, Mei; Yang, Xiao-bao

2014-01-01

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. PMID:24895659

Tasks of research in forensic medicine - different study types in clinical research and forensic medicine.

PubMed

Madea, Burkhard; Saukko, Pekka; Musshoff, Frank

2007-01-17

In the last years the research output of forensic medicine has sometimes been regarded as insufficient and as of poor quality, especially when parameters as impact factors and external funding were taken into account. However, forensic medicine has different tasks compared to clinical medicine. The main difference between basic subjects, clinical and forensic medicine is not a lack of scientific efficiency in forensic medicine but is a result of the questions asked, the available methods and specific aims. In contrast to natural-scientific research, forensic science has furthermore important intersections with arts and socio-scientific disciplines. Etiologic and pathogenetic research is of only limited relevance in forensic medicine. Thus, forensic medicine is excluded from these research fields, which are mainly supported by external funding. In forensic medicine research mainly means applied research regarding findings, the probative value and reconstruction as well as examination at different points of intersection between medicine and law. Clinical types of research such as controlled randomised, prospective cross-sectional, cohort or case-control studies can only rarely be applied in forensic medicine due to the area specific research fields (e.g. thantatology, violent death, vitality, traffic medicine, analytical toxicology, hemogenetics and stain analysis). The types of studies which are successfully established in forensic medicine are comparison of methods, sensitivity studies, validation of methods, kinetic examinations etc. Tasks of research in forensic medicine and study types, which may be applied will be addressed.

Understanding the Influence of Race/Ethnicity, Gender, and Class on Inequalities in Academic and Non-Academic Outcomes among Eighth-Grade Students: Findings from an Intersectionality Approach

PubMed Central

Bécares, Laia; Priest, Naomi

2015-01-01

Socioeconomic, racial/ethnic, and gender inequalities in academic achievement have been widely reported in the US, but how these three axes of inequality intersect to determine academic and non-academic outcomes among school-aged children is not well understood. Using data from the US Early Childhood Longitudinal Study—Kindergarten (ECLS-K; N = 10,115), we apply an intersectionality approach to examine inequalities across eighth-grade outcomes at the intersection of six racial/ethnic and gender groups (Latino girls and boys, Black girls and boys, and White girls and boys) and four classes of socioeconomic advantage/disadvantage. Results of mixture models show large inequalities in socioemotional outcomes (internalizing behavior, locus of control, and self-concept) across classes of advantage/disadvantage. Within classes of advantage/disadvantage, racial/ethnic and gender inequalities are predominantly found in the most advantaged class, where Black boys and girls, and Latina girls, underperform White boys in academic assessments, but not in socioemotional outcomes. In these latter outcomes, Black boys and girls perform better than White boys. Latino boys show small differences as compared to White boys, mainly in science assessments. The contrasting outcomes between racial/ethnic and gender minorities in self-assessment and socioemotional outcomes, as compared to standardized assessments, highlight the detrimental effect that intersecting racial/ethnic and gender discrimination have in patterning academic outcomes that predict success in adult life. Interventions to eliminate achievement gaps cannot fully succeed as long as social stratification caused by gender and racial discrimination is not addressed. PMID:26505623

Multiuse trail intersection safety analysis: A crowdsourced data perspective.

PubMed

Jestico, Ben; Nelson, Trisalyn A; Potter, Jason; Winters, Meghan

2017-06-01

Real and perceived concerns about cycling safety are a barrier to increased ridership in many cities. Many people prefer to bike on facilities separated from motor vehicles, such as multiuse trails. However, due to underreporting, cities lack data on bike collisions, especially along greenways and multiuse paths. We used a crowdsourced cycling incident dataset (2005-2016) from BikeMaps.org for the Capital Regional District (CRD), BC, Canada. Our goal was to identify design characteristics associated with unsafe intersections between multiuse trails and roads. 92.8% of mapped incidents occurred between 2014 and 2016. We extracted both collision and near miss incidents at intersections from BikeMaps.org. We conducted site observations at 32 intersections where a major multiuse trail intersected with roads. We compared attributes of reported incidents at multiuse trail-road intersections to those at road-road intersections. We then used negative binomial regression to model the relationship between the number of incidents and the infrastructure characteristics at multiuse trail-road intersections. We found a higher proportion of collisions (38%, or 17/45 total reports) at multiuse trail-road intersections compared to road-road intersections (23%, or 62/268 total reports). A higher proportion of incidents resulted in an injury at multiuse trail-road intersections compared to road-road intersections (33% versus 15%). Cycling volumes, vehicle volumes, and trail sight distance were all associated with incident frequency at multiuse trail-road intersections. Supplementing traditional crash records with crowdsourced cycling incident data provides valuable evidence on cycling safety at intersections between multiuse trails and roads, and more generally, when conflicts occur between diverse transportation modes. Copyright © 2017. Published by Elsevier Ltd.

2. VIEW OF THE EXPERIMENT CONTROL PANEL IN 1970. THE ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. VIEW OF THE EXPERIMENT CONTROL PANEL IN 1970. THE NUCLEAR SAFETY GROUP CONDUCTED ABOUT 1,700 CRITICAL MASS EXPERIMENTS USING URANIUM AND PLUTONIUM IN SOLUTIONS (900 TESTS), COMPACTED POWDER (300), AND METALLIC FORMS (500). ALL 1,700 CRITICALITY ASSEMBLIES WERE CONTROLLED FROM THIS PANEL. - Rocky Flats Plant, Critical Mass Laboratory, Intersection of Central Avenue & 86 Drive, Golden, Jefferson County, CO

Eliminating sun glare disturbance at signalized intersections by a vehicle to infrastructure wireless communication : final report.

DOT National Transportation Integrated Search

2016-05-01

Due to sun glare disturbances, drivers may encounter fatal threats on roadways, particularly at signalized intersections. Many studies have attempted to develop applicable solutions, such as avoiding sun positions, road geometric redirections, and we...

Characterize dynamic dilemma zone and minimize its effect at signalized intersections : December 26, 2008.

DOT National Transportation Integrated Search

2008-12-26

Dilemma zone at signalized intersection has been recognized as a major potential causing rearend : crashes, and has been widely studied by researches since it was initially proposed as the : GHM model in 1960. However, concepts conventionally defined...

Characterize dynamic dilemma zone and minimize its effect at signalized intersections.

DOT National Transportation Integrated Search

2008-12-26

Dilemma zone at signalized intersection has been recognized as a major potential causing rearend : and right-angle crashes, and has been widely studied by researches since it was initially : proposed as the GHM model in 1960. However, concepts conven...

A Study of the Traffic Safety at Reduced Conflict Intersections In Minnesota

DOT National Transportation Integrated Search

2017-05-23

In 2010, the Minnesota Department of Transportation installed the first Reduced Conflict Intersection (RCI) in the City of Willmar. Since 2010, seven more were constructed, with more planned. The RCI concept is gaining popularity in several states, i...

Repeated Challenge Studies: A Comparison of Union-Intersection Testing with Linear Modeling.

ERIC Educational Resources Information Center

Levine, Richard A.; Ohman, Pamela A.

1997-01-01

Challenge studies can be used to see whether there is a causal relationship between an agent of interest and a response. An approach based on union-intersection testing is presented that allows researchers to examine observations on a single subject and test the hypothesis of interest. An application using psychological data is presented. (SLD)

The Intersection of Imagery Ability, Imagery Use, and Learning Style: An Exploratory Study

ERIC Educational Resources Information Center

Bolles, Gina; Chatfield, Steven J.

2009-01-01

This study explores the intersection of the individual's imagery ability, imagery use in dance training and performance, and learning style. Thirty-four intermediate-level ballet and modern dance students at the University of Oregon completed the Movement Imagery Questionnaire-Revised (MIQ-R) and Kolb's Learning Style Inventory-3 (LSI-3). The four…

A Monte Carlo Study Investigating the Influence of Item Discrimination, Category Intersection Parameters, and Differential Item Functioning Patterns on the Detection of Differential Item Functioning in Polytomous Items

ERIC Educational Resources Information Center

Thurman, Carol

2009-01-01

The increased use of polytomous item formats has led assessment developers to pay greater attention to the detection of differential item functioning (DIF) in these items. DIF occurs when an item performs differently for two contrasting groups of respondents (e.g., males versus females) after controlling for differences in the abilities of the…

Neutron transport analysis for nuclear reactor design

DOEpatents

Vujic, Jasmina L.

1993-01-01

Replacing regular mesh-dependent ray tracing modules in a collision/transfer probability (CTP) code with a ray tracing module based upon combinatorial geometry of a modified geometrical module (GMC) provides a general geometry transfer theory code in two dimensions (2D) for analyzing nuclear reactor design and control. The primary modification of the GMC module involves generation of a fixed inner frame and a rotating outer frame, where the inner frame contains all reactor regions of interest, e.g., part of a reactor assembly, an assembly, or several assemblies, and the outer frame, with a set of parallel equidistant rays (lines) attached to it, rotates around the inner frame. The modified GMC module allows for determining for each parallel ray (line), the intersections with zone boundaries, the path length between the intersections, the total number of zones on a track, the zone and medium numbers, and the intersections with the outer surface, which parameters may be used in the CTP code to calculate collision/transfer probability and cross-section values.

Neutron transport analysis for nuclear reactor design

DOEpatents

Vujic, J.L.

1993-11-30

Replacing regular mesh-dependent ray tracing modules in a collision/transfer probability (CTP) code with a ray tracing module based upon combinatorial geometry of a modified geometrical module (GMC) provides a general geometry transfer theory code in two dimensions (2D) for analyzing nuclear reactor design and control. The primary modification of the GMC module involves generation of a fixed inner frame and a rotating outer frame, where the inner frame contains all reactor regions of interest, e.g., part of a reactor assembly, an assembly, or several assemblies, and the outer frame, with a set of parallel equidistant rays (lines) attached to it, rotates around the inner frame. The modified GMC module allows for determining for each parallel ray (line), the intersections with zone boundaries, the path length between the intersections, the total number of zones on a track, the zone and medium numbers, and the intersections with the outer surface, which parameters may be used in the CTP code to calculate collision/transfer probability and cross-section values. 28 figures.

An electronic beam splitter realized with crossed graphene nanoribbons

NASA Astrophysics Data System (ADS)

Frederiksen, Thomas; Brandimarte, Pedro; Engelund, Mads; Papior, Nick; Garcia-Lekue, Aran; Sanchez-Portal, Daniel

Graphene nanoribbons (GNRs) are promising components in future nanoelectronics. We have explored a prototype 4-terminal semiconducting device formed by two crossed armchair GNRs (AGNRs) using state-of-the-art first-principles transport methods. We analyze in detail the roles of intersection angle, stacking order, inter-GNR separation, and finite voltages on the transport characteristics. Interestingly, when the AGNRs intersect at θ =60° , electrons injected from one terminal can be split into two outgoing waves with a tunable ratio around 50 % and with almost negligible back-reflection. The splitted electron wave is found to propagate partly straight across the intersection region in one ribbon and partly in one direction of the other ribbon, i.e., in analogy of an optical beam splitter. Our simulations further identify realistic conditions for which this semiconducting device can act as a mechanically controllable electronic beam splitter with possible applications in carbon-based quantum electronic circuits and electron optics. FP7-FET-ICT PAMS (610446), MAT2013-46593-C6-2-P, IT-756-13.

Exploring stop-go decision zones at rural high-speed intersections with flashing green signal and insufficient yellow time in China.

PubMed

Tang, Keshuang; Xu, Yanqing; Wang, Fen; Oguchi, Takashi

2016-10-01

The objective of this study is to empirically analyze and model the stop-go decision behavior of drivers at rural high-speed intersections in China, where a flashing green signal of 3s followed by a yellow signal of 3s is commonly applied to end a green phase. 1, 186 high-resolution vehicle trajectories were collected at four typical high-speed intersection approaches in Shanghai and used for the identification of actual stop-go decision zones and the modeling of stop-go decision behavior. Results indicate that the presence of flashing green significantly changed the theoretical decision zones based on the conventional Dilemma Zone theory. The actual stop-go decision zones at the study intersections were thus formulated and identified based on the empirical data. Binary Logistic model and Fuzzy Logic model were then developed to further explore the impacts of flashing green on the stop-go behavior of drivers. It was found that the Fuzzy Logic model could produce comparably good estimation results as compared to the traditional Binary Logistic models. The findings of this study could contribute the development of effective dilemma zone protection strategies, the improvement of stop-go decision model embedded in the microscopic traffic simulation software and the proper design of signal change and clearance intervals at high-speed intersections in China. Copyright © 2016 Elsevier Ltd. All rights reserved.

Safety analysis of urban arterials at the meso level.

PubMed

Li, Jia; Wang, Xuesong

2017-11-01

Urban arterials form the main structure of street networks. They typically have multiple lanes, high traffic volume, and high crash frequency. Classical crash prediction models investigate the relationship between arterial characteristics and traffic safety by treating road segments and intersections as isolated units. This micro-level analysis does not work when examining urban arterial crashes because signal spacing is typically short for urban arterials, and there are interactions between intersections and road segments that classical models do not accommodate. Signal spacing also has safety effects on both intersections and road segments that classical models cannot fully account for because they allocate crashes separately to intersections and road segments. In addition, classical models do not consider the impact on arterial safety of the immediately surrounding street network pattern. This study proposes a new modeling methodology that will offer an integrated treatment of intersections and road segments by combining signalized intersections and their adjacent road segments into a single unit based on road geometric design characteristics and operational conditions. These are called meso-level units because they offer an analytical approach between micro and macro. The safety effects of signal spacing and street network pattern were estimated for this study based on 118 meso-level units obtained from 21 urban arterials in Shanghai, and were examined using CAR (conditional auto regressive) models that corrected for spatial correlation among the units within individual arterials. Results showed shorter arterial signal spacing was associated with higher total and PDO (property damage only) crashes, while arterials with a greater number of parallel roads were associated with lower total, PDO, and injury crashes. The findings from this study can be used in the traffic safety planning, design, and management of urban arterials. Copyright © 2017 Elsevier Ltd. All rights reserved.

Remotely Accessed Vehicle Traffic Management System

NASA Astrophysics Data System (ADS)

Al-Alawi, Raida

2010-06-01

The ever increasing number of vehicles in most metropolitan cities around the world and the limitation in altering the transportation infrastructure, led to serious traffic congestion and an increase in the travelling time. In this work we exploit the emergence of novel technologies such as the internet, to design an intelligent Traffic Management System (TMS) that can remotely monitor and control a network of traffic light controllers located at different sites. The system is based on utilizing Embedded Web Servers (EWS) technology to design a web-based TMS. The EWS located at each intersection uses IP technology for communicating remotely with a Central Traffic Management Unit (CTMU) located at the traffic department authority. Friendly GUI software installed at the CTMU will be able to monitor the sequence of operation of the traffic lights and the presence of traffic at each intersection as well as remotely controlling the operation of the signals. The system has been validated by constructing a prototype that resembles the real application.

An analysis on intersectional collaboration on non-communicable chronic disease prevention and control in China: a cross-sectional survey on main officials of community health service institutions.

PubMed

Li, Xing-Ming; Rasooly, Alon; Peng, Bo; JianWang; Xiong, Shu-Yu

2017-11-10

Our study aimed to design a tool of evaluating intersectional collaboration on Non-communicable Chronic Disease (NCD) prevention and control, and further to understand the current status of intersectional collaboration in community health service institutions of China. We surveyed 444 main officials of community health service institutions in Beijing, Tianjin, Hubei and Ningxia regions of China in 2014 by using a questionnaire. A model of collaboration measurement, including four relational dimensions of governance, shared goals and vision, formalization and internalization, was used to compare the scores of evaluation scale in NCD management procedures across community healthcare institutions and other ones. Reliability and validity of the evaluation tool on inter-organizational collaboration on NCD prevention and control were verified. The test on tool evaluating inter-organizational collaboration in community NCD management revealed a good reliability and validity (Cronbach's Alpha = 0.89,split-half reliability = 0.84, the variance contribution rate of an extracted principal component = 49.70%). The results of inter-organizational collaboration of different departments and management segments showed there were statistically significant differences in formalization dimension for physical examination (p = 0.01).There was statistically significant difference in governance dimension, formalization dimension and total score of the collaboration scale for health record sector (p = 0.01,0.00,0.00). Statistical differences were found in the formalization dimension for exercise and nutrition health education segment (p = 0.01). There were no statistically significant difference in formalization dimension of medication guidance for psychological consultation, medical referral service and rehabilitation guidance (all p > 0.05). The multi-department collaboration mechanism of NCD prevention and control has been rudimentarily established. Community management institutions and general hospitals are more active in participating in community NCD management with better collaboration score, whereas the CDC shows relatively poor collaboration in China. Xing-ming Li and Alon Rasooly have the same contribution to the paper. Xing-ming Li and Alon Rasooly listed as the same first author.

Safety evaluation of intersections with dynamic use of exit-lanes for left-turn using field data.

PubMed

Zhao, Jing; Liu, Yue

2017-05-01

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. Copyright © 2017 Elsevier Ltd. All rights reserved.

Intersecting surface defects and instanton partition functions

NASA Astrophysics Data System (ADS)

Pan, Yiwen; Peelaers, Wolfger

2017-07-01

We analyze intersecting surface defects inserted in interacting four-dimensional N=2 supersymmetric quantum field theories. We employ the realization of a class of such systems as the infrared fixed points of renormalization group flows from larger theories, triggered by perturbed Seiberg-Witten monopole-like configurations, to compute their partition functions. These results are cast into the form of a partition function of 4d/2d/0d coupled systems. Our computations provide concrete expressions for the instanton partition function in the presence of intersecting defects and we study the corresponding ADHM model.

Taking an intersectional approach to define latent classes of socioeconomic status, ethnicity and migration status for psychiatric epidemiological research.

PubMed

Goodwin, L; Gazard, B; Aschan, L; MacCrimmon, S; Hotopf, M; Hatch, S L

2017-04-09

Inequalities in mental health are well documented using individual social statuses such as socioeconomic status (SES), ethnicity and migration status. However, few studies have taken an intersectional approach to investigate inequalities in mental health using latent class analysis (LCA). This study will examine the association between multiple indicator classes of social identity with common mental disorder (CMD). Data on CMD symptoms were assessed in a diverse inner London sample of 1052 participants in the second wave of the South East London Community Health study. LCA was used to define classes of social identity using multiple indicators of SES, ethnicity and migration status. Adjusted associations between CMD and both individual indicators and multiple indicators of social identity are presented. LCA identified six groups that were differentiated by varying levels of privilege and disadvantage based on multiple SES indicators. This intersectional approach highlighted nuanced differences in odds of CMD, with the economically inactive group with multiple levels of disadvantage most likely to have a CMD. Adding ethnicity and migration status further differentiated between groups. The migrant, economically inactive and White British, economically inactive classes both had increased odds of CMD. This is the first study to examine the intersections of SES, ethnicity and migration status with CMD using LCA. Results showed that both the migrant, economically inactive and the White British, economically inactive classes had a similarly high prevalence of CMD. Findings suggest that LCA is a useful methodology for investigating health inequalities by intersectional identities.

C'est La Vie! The Game of Social Life: Using an Intersectionality Approach to Teach About Privilege and Structural Inequality

ERIC Educational Resources Information Center

Bramesfeld, Kosha D.; Good, Arla

2016-01-01

In this article, we present the results of two studies that evaluated an experiential intersectionality awareness activity, "C'est La Vie: The Game of Social Life." For Study 1 (N = 55), we content analyzed students' short answer responses about inequality written before and after playing "C'est La Vie." Study 2 compared a…

Neighborhood design and walking trips in ten U.S. metropolitan areas.

PubMed

Boer, Rob; Zheng, Yuhui; Overton, Adrian; Ridgeway, Gregory K; Cohen, Deborah A

2007-04-01

Despite substantial evidence for neighborhood characteristics correlating with walking, so far there has been limited attention to possible practical implications for neighborhood design. This study investigates to what extent design guidelines are likely to stimulate walking. Four of the New Urbanism Smart Scorecard criteria and two other measures were tested for their influence on walking. Data were obtained from the 1995 National Personal Transportation Survey, U.S. Census 2000, and InfoUSA. Propensity-score methodology was used to control for potential confounders. Higher levels of business diversity and higher percentages of four-way intersections were associated with more walking. For example, the odds ratio (OR) for walking in a neighborhood with four business types present compared to three business types was 1.24 (confidence interval [CI] 1.07-1.44) and neighborhoods with 50%-74% four-way intersections had an OR for walking of 1.4 (CI 1.09-1.78) relative to those with 25%-49% four-way intersections. The effects of housing density on walking are mixed. Higher parking pressure and older median housing age did not significantly affect walking after covariate adjustment. Block length did not appear to be associated with walking. When considering the New Urbanism Smart Scorecard from the perspective walking, some, but not all, of its criteria that appear to have a correlation with walking are likely to be useful for designing walkable communities.

Remote infrared signage evaluation for transit stations and intersections.

PubMed

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.

Non-airborne conflicts: The causes and effects of runway transgressions

NASA Technical Reports Server (NTRS)

Tarrel, Richard J.

1985-01-01

The 1210 ASRS runway transgression reports are studied and expanded to yield descriptive statistics. Additionally, a one of three subset was studied in detail for purposes of evaluating the causes, risks, and consequences behind trangression events. Occurrences are subdivided by enabling factor and flight phase designations. It is concluded that a larger risk of collision is associated with controller enabled departure transgressions over all other categories. The influence of this type is especially evident during the period following the air traffic controllers' strike of 1981. Causal analysis indicates that, coincidentally, controller enabled departure transgressions also, show the strongest correlations between causal factors. It shows that departure errors occur more often when visibility is reduced, and when multiple takeoff runways or intersection takeoffs are employed. In general, runway transgressions attributable to both pilot and controller errors arise from three problem areas: information transfer, awareness, and spatial judgement. Enhanced awareness by controllers will probably reduce controller enabled incidents.

6. COMPRESSOR CONTROL PANELS: AT LEFT, 6,000 P.S.I. PANEL, CIRCA ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. COMPRESSOR CONTROL PANELS: AT LEFT, 6,000 P.S.I. PANEL, CIRCA 1957; AT RIGHT, FACING CAMERA, 10,000 P.S.I. PANEL. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Helium Compression Plant, Test Area 1-115, intersection of Altair & Saturn Boulevards, Boron, Kern County, CA

Caring labour, intersectionality and worker satisfaction: an analysis of the National Nursing Assistant Study (NNAS).

PubMed

Rakovski, Carter C; Price-Glynn, Kim

2010-03-01

Caring labour in long-term care settings is increasingly important as the US population ages. Ethnographic research on nursing assistants (NAs) portrays nursing home care as routine and fast paced in facilities that emphasise life maintenance more than care. Recent interview-based and small quantitative studies describe a mix of positive and negative aspects of NA work, including the rewards of caring, despite shortcomings in working conditions and pay. The current study continues this research but, for the first time, using national data. The 2004 Centers for Disease Control and Prevention's National Nursing Assistant Study (NNAS) provides survey data from 3,017 NAs working in long-term care facilities across the US. The NNAS results confirm the importance and centrality of caring to NAs' work. NAs motivated by caring for others were significantly more satisfied with their jobs than those motivated by other reasons, such as convenience or salary. Overall, NAs report surprisingly high job satisfaction, particularly with learning new skills, doing challenging work, and organisational support for caring labour. Areas of dissatisfaction were salary, time for reproductive labour, and turnover. Intersectional analysis revealed race and citizenship played a stronger role than gender in worker satisfaction.

Force sensor

DOEpatents

Grahn, A.R.

1993-05-11

A force sensor and related method for determining force components is described. The force sensor includes a deformable medium having a contact surface against which a force can be applied, a signal generator for generating signals that travel through the deformable medium to the contact surface, a signal receptor for receiving the signal reflected from the contact surface, a generation controller, a reception controller, and a force determination apparatus. The signal generator has one or more signal generation regions for generating the signals. The generation controller selects and activates the signal generation regions. The signal receptor has one or more signal reception regions for receiving signals and for generating detections signals in response thereto. The reception controller selects signal reception regions and detects the detection signals. The force determination apparatus measures signal transit time by timing activation and detection and, optionally, determines force components for selected cross-field intersections. The timer which times by activation and detection can be any means for measuring signal transit time. A cross-field intersection is defined by the overlap of a signal generation region and a signal reception region.

Force sensor

DOEpatents

Grahn, Allen R.

1993-01-01

A force sensor and related method for determining force components. The force sensor includes a deformable medium having a contact surface against which a force can be applied, a signal generator for generating signals that travel through the deformable medium to the contact surface, a signal receptor for receiving the signal reflected from the contact surface, a generation controller, a reception controller, and a force determination apparatus. The signal generator has one or more signal generation regions for generating the signals. The generation controller selects and activates the signal generation regions. The signal receptor has one or more signal reception regions for receiving signals and for generating detections signals in response thereto. The reception controller selects signal reception regions and detects the detection signals. The force determination apparatus measures signal transit time by timing activation and detection and, optionally, determines force components for selected cross-field intersections. The timer which times by activation and detection can be any means for measuring signal transit time. A cross-field intersection is defined by the overlap of a signal generation region and a signal reception region.

Traffic signal operations handbook : second edition.

DOT National Transportation Integrated Search

2011-10-01

"This handbook provides guidelines for timing traffic control signals at intersections that operate in isolation : or as part of a coordinated signal system. The guidelines are intended to describe best practices, as identified : through interviews w...

NORTHEAST FACADE AND ONESTORY WING, VIEW FACING SOUTHSOUTHWEST. Naval ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

NORTHEAST FACADE AND ONE-STORY WING, VIEW FACING SOUTH-SOUTHWEST. - Naval Air Station Barbers Point, Control Tower & Aviation Operations Building, Near intersection of runways between Hangar 110 & Building 115, Ewa, Honolulu County, HI

Evaluation of signal timing and coordination procedures.

DOT National Transportation Integrated Search

1985-01-01

Based on a review of available literature, recommended procedures for timing the various types of signals are provided. Specifically, procedures are included for both pretimed and vehicle-actuated controllers located at isolated intersections and at ...

Characteristics of traffic flow at a non-signalized intersection in the framework of game theory

NASA Astrophysics Data System (ADS)

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.

Safety Effectiveness of Stop-Sign Beacons : A Cross-Sectional Study

DOT National Transportation Integrated Search

2018-02-02

Rural intersections account for 16% of fatalities in rural areas (IIHS 2016). Rural intersection crashes are frequently a result of drivers failing to yield to the right of way. Failure to yield right-of-way (FTYROW) may be due to speeding, which ...

The impact of general permissive right and left turn on red legislation in Virginia.

DOT National Transportation Integrated Search

1978-01-01

Right turn on red (RTOR) maneuvers have been permitted at signalized intersections in Virginia since 1972. However, until January 1, 1977, following a study requested by the General Assembly, the maneuver was restricted to intersections at which a si...

The effects of pedestrian countdown timers on safety and efficiency of operations at signalized intersections.

DOT National Transportation Integrated Search

2011-12-01

Pedestrian countdown timers are becoming common at urban and suburban intersections. The added information that : pedestrian countdown timers provide to pedestrians can also be used by approaching drivers. A before-and-after case study : on the effec...

“It’s an Uphill Battle Everyday”: Intersectionality, Low-Income Black Heterosexual Men, and Implications for HIV Prevention Research and Interventions

PubMed Central

Bowleg, Lisa; Teti, Michelle; Malebranche, David J.; Tschann, Jeanne M.

2012-01-01

This interview study, the initial qualitative phase of a larger mixed methods HIV prevention study focused on Black heterosexual men, used intersectionality as a theoretical framework to explore: (1) How a sample of Black heterosexual men describe and experience the multiple intersections of race, gender, and SES; and (2) How these descriptions reflected interlocking systems of social inequality for Black men at the social-structural level. Participants were 30 predominantly low-income self-identified Black heterosexual men between the ages of 18 and 44. Analyses highlighted four themes that demonstrate how participants’ individual-level experiences as Black men reflect macro social-structural inequality: (1) racial discrimination and microaggressions; (2) unemployment; (3) incarceration; and (4) police surveillance and harassment. We discuss the study’s findings within the context of social-structural factors that disproportionately and adversely impact Black men. We also highlight the implications of the intersectionality perspective for HIV prevention research and interventions for Black heterosexual men. PMID:23482810

Failure at Frame-Stringer Intersections in PRSEUS Panels

NASA Technical Reports Server (NTRS)

Jegley, Dawn C.

2012-01-01

NASA, the Air Force Research Laboratory and The Boeing Company have worked to develop new low-cost, light-weight composite structures for aircraft. A Pultruded Rod Stitched Efficient Unitized Structure (PRSEUS) concept has been developed which offers advantages over traditional metallic structures. In this concept a stitched carbon-epoxy material system has been developed with the potential for reducing the weight and cost of transport aircraft structure by eliminating fasteners, thereby reducing part count and labor. By adding unidirectional carbon rods to the top of stiffeners, the panel becomes more structurally efficient. This combination produces a more damage tolerant design. This study focuses on the intersection between the rod-stiffener and the foam-filled frame in a PRSEUS specimen. Compression loading is considered, which induces stress concentrations at the intersection point that can lead to failures. An experiment with accompanying analysis for a single-frame specimen is described, followed by a parametric study of simple reinforcements to reduce strains in the intersection region.

Vehicular headways on signalized intersections: theory, models, and reality

NASA Astrophysics Data System (ADS)

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.

Transcriptional control of Sost in bone [Transcriptional control of Sclerostin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sebastian, Aimy; Loots, Gabriela G.

Sclerostin is an osteocyte derived negative regulator of bone formation. A highly specific expression pattern and the exclusive bone phenotype have made Sclerostin an attractive target for therapeutic intervention in treating metabolic bone diseases such as osteoporosis and in facilitating fracture repair. Understanding the molecular mechanisms that regulate Sclerostin transcription is of great interest as it may unveil new avenues for therapeutic approaches. Such studies may also elucidate how various signaling pathways intersect to modulate bone metabolism. Furthermore we review the current understanding of the upstream molecular mechanisms that regulate Sost/SOST transcription, in bone.

Transcriptional control of Sost in bone [Transcriptional control of Sclerostin

DOE PAGES

Sebastian, Aimy; Loots, Gabriela G.

2016-10-19

Sclerostin is an osteocyte derived negative regulator of bone formation. A highly specific expression pattern and the exclusive bone phenotype have made Sclerostin an attractive target for therapeutic intervention in treating metabolic bone diseases such as osteoporosis and in facilitating fracture repair. Understanding the molecular mechanisms that regulate Sclerostin transcription is of great interest as it may unveil new avenues for therapeutic approaches. Such studies may also elucidate how various signaling pathways intersect to modulate bone metabolism. Furthermore we review the current understanding of the upstream molecular mechanisms that regulate Sost/SOST transcription, in bone.

Longitudinal vortex control - Techniques and applications (The 32nd Lanchester Lecture)

NASA Technical Reports Server (NTRS)

Bushnell, D. M.

1992-01-01

A summary is presented of vortex control applications and current techniques for the control of longitudinal vortices produced by bodies, leading edges, tips and intersections. Vortex control has up till now been performed by many approaches in an empirical fashion, assisted by the essentially inviscid nature of much of longitudinal vortex behavior. Attention is given to Reynolds number sensitivities, vortex breakdown and interactions, vortex control on highly swept wings, and vortex control in juncture flows.

Study on Performance of Intersection Around The Underpass Using Micro Simulation Program

NASA Astrophysics Data System (ADS)

Arliansyah, J.; Bawono, R. T.

2018-03-01

In order to overcome the problems of congestion at the major intersections in Palembang City, there have been grade separation constructions in the form of flyover or underpass. One of them is the intersection of Patal Pusri Underpass. The smooth traffic due to the underpass construction needs to be balanced by the arrangement management at the intersections located close to the underpass to get the best network performance since both affect each other performance. The Taman Kenten and Seduduk Putih junctions which are just 569 and 226 meters from the underpass of Patal Pusri has to be analyzed for its needs of management and traffic arrangements to reduce its impact on the performance of the intersection of Patal Pusri or vice versa. Some alternatives of management and traffic arrangements were developed to get the best solutions and the Vissim 8.00 microsimulation program was used to evaluate the performance of intersections in the network where the compared parameters are the value of the queue length and average delay. The results of the analysis and the conducted modeling show that the best solution to optimize the performance of the two junctions are to make geometric changes and diversion of traffic flow at Seduduk Putih Junction and making geometric changes at Taman Kenten Junction.

Kinematics at the Intersection of the Garlock and Death Valley Fault Zones, California: Integration of TM Data and Field Studies

NASA Technical Reports Server (NTRS)

Verosub, Kenneth L.; Brady, Roland H., III; Abrams, Michael

1989-01-01

Kinematic relationships at the intersection of the southern Death Valley and Garlock fault zones were examined to identify and delineate the eastern structural boundary between the Mojave and the Basin and Range geologic terrains, and to construct a model for the evolution of this boundary through time. In order to accomplish this, satellite imagery was combined with field investigations to study six areas in the vicinity of the intersection, or possible extensions, of the fault zones. The information gathered from these areas allows the test of various hypotheses that were proposed to explain the interaction between the Death Valley and Garlock fault zones.

Traffic condition with road upgrading during construction and operation stages based on level-of-service (LOS)

NASA Astrophysics Data System (ADS)

Tay, A. C.; Lee, H. H.

2018-04-01

In this study, traffic survey was done at signalized intersection of both ends of an upgrading road during morning and afternoon peak hours throughout construction period. The intersections of Tudan Road located at Miri City in Sarawak State, Malaysia were chosen as study sites. The aim of this research was to investigate the traffic condition for the signalized intersections of a R3 secondary road that being upgrading to standard U5 dual carriageway during peak hours for construction and operation stages. Data collected from these sites were analyzed according to Highway Capacity Manual (HCM) 2010. From the results, the level-of-services (LOS) of Kuala Baram By Pass Road intersection improved from Level F to Level E at operation stage for weekday during peak hours in the morning. LOS of Lutong-Kuala Baram Road intersection at construction stage were Level C during peak hours in the morning and Level D during peak hours in the afternoon for weekends. However, the LOS during both peak hours for weekends were projected to improve to Level B at the operation stage. It proved that the road construction has affected LOS, and this temporary issue can be solved after the upgraded road is in operation.

Particle tracking approach for transport in three-dimensional discrete fracture networks: Particle tracking in 3-D DFNs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Makedonska, Nataliia; Painter, Scott L.; Bui, Quan M.

The discrete fracture network (DFN) model is a method to mimic discrete pathways for fluid flow through a fractured low-permeable rock mass, and may be combined with particle tracking simulations to address solute transport. However, experience has shown that it is challenging to obtain accurate transport results in three-dimensional DFNs because of the high computational burden and difficulty in constructing a high-quality unstructured computational mesh on simulated fractures. We present a new particle tracking capability, which is adapted to control volume (Voronoi polygons) flow solutions on unstructured grids (Delaunay triangulations) on three-dimensional DFNs. The locally mass-conserving finite-volume approach eliminates massmore » balance-related problems during particle tracking. The scalar fluxes calculated for each control volume face by the flow solver are used to reconstruct a Darcy velocity at each control volume centroid. The groundwater velocities can then be continuously interpolated to any point in the domain of interest. The control volumes at fracture intersections are split into four pieces, and the velocity is reconstructed independently on each piece, which results in multiple groundwater velocities at the intersection, one for each fracture on each side of the intersection line. This technique enables detailed particle transport representation through a complex DFN structure. Verified for small DFNs, the new simulation capability enables numerical experiments on advective transport in large DFNs to be performed. As a result, we demonstrate this particle transport approach on a DFN model using parameters similar to those of crystalline rock at a proposed geologic repository for spent nuclear fuel in Forsmark, Sweden.« less

Comparing the role of fuel breaks across southern California national forests

USGS Publications Warehouse

Syphard, Alexandra D.; Keeley, Jon E.; Brennan, Teresa J.

2011-01-01

Fuel treatment of wildland vegetation is the primary approach advocated for mitigating fire risk at the wildland-urban interface (WUI), but little systematic research has been conducted to understand what role fuel treatments play in controlling large fires, which factors influence this role, or how the role of fuel treatments may vary over space and time. We assembled a spatial database of fuel breaks and fires from the last 30 years in four southern California national forests to better understand which factors are consistently important for fuel breaks in the control of large fires. We also explored which landscape features influence where fires and fuel breaks are most likely to intersect. The relative importance of significant factors explaining fuel break outcome and number of fire and fuel break intersections varied among the forests, which reflects high levels of regional landscape diversity. Nevertheless, several factors were consistently important across all the forests. In general, fuel breaks played an important role in controlling large fires only when they facilitated fire management, primarily by providing access for firefighting activities. Fire weather and fuel break maintenance were also consistently important. Models and maps predicting where fuel breaks and fires are most likely to intersect performed well in the regions where the models were developed, but these models did not extend well to other regions, reflecting how the environmental controls of fire regimes vary even within a single ecoregion. Nevertheless, similar mapping methods could be adopted in different landscapes to help with strategic location of fuel breaks. Strategic location of fuel breaks should also account for access points near communities, where fire protection is most important.

Particle tracking approach for transport in three-dimensional discrete fracture networks: Particle tracking in 3-D DFNs

DOE PAGES

Makedonska, Nataliia; Painter, Scott L.; Bui, Quan M.; ...

2015-09-16

The discrete fracture network (DFN) model is a method to mimic discrete pathways for fluid flow through a fractured low-permeable rock mass, and may be combined with particle tracking simulations to address solute transport. However, experience has shown that it is challenging to obtain accurate transport results in three-dimensional DFNs because of the high computational burden and difficulty in constructing a high-quality unstructured computational mesh on simulated fractures. We present a new particle tracking capability, which is adapted to control volume (Voronoi polygons) flow solutions on unstructured grids (Delaunay triangulations) on three-dimensional DFNs. The locally mass-conserving finite-volume approach eliminates massmore » balance-related problems during particle tracking. The scalar fluxes calculated for each control volume face by the flow solver are used to reconstruct a Darcy velocity at each control volume centroid. The groundwater velocities can then be continuously interpolated to any point in the domain of interest. The control volumes at fracture intersections are split into four pieces, and the velocity is reconstructed independently on each piece, which results in multiple groundwater velocities at the intersection, one for each fracture on each side of the intersection line. This technique enables detailed particle transport representation through a complex DFN structure. Verified for small DFNs, the new simulation capability enables numerical experiments on advective transport in large DFNs to be performed. As a result, we demonstrate this particle transport approach on a DFN model using parameters similar to those of crystalline rock at a proposed geologic repository for spent nuclear fuel in Forsmark, Sweden.« less

Evaluating the relationship between the driver and roadway to address rural intersection safety using the SHRP 2 naturalistic driving study data.

DOT National Transportation Integrated Search

2016-02-01

Rural intersections account for 30% of crashes in rural areas and 6% of all fatal crashes, representing a significant but poorly : understood safety problem. Transportation agencies have traditionally implemented countermeasures to address rural inte...

Field testing and implementation of dilemma zone protection and signal coordination at closely-spaced high-speed intersections : final report, May 19, 2005.

DOT National Transportation Integrated Search

2005-05-01

The report presents the details of a study carried out to test and implement a dilemma zone protection technique at three high-speed closely-spaced intersections on Roosevelt Blvd in Middletown, Ohio.

Places and networks : the changing landscape of transportation and technology, final summary report of the STAR-TEA 21 project.

DOT National Transportation Integrated Search

2008-12-01

Over the past six years, researchers from the University of Minnesota have studied the many ways in which transportation and technology intersect. Their work has explored these intersections from many perspectives, from ways intelligent transportatio...

Teaching Science from Cultural Points of Intersection

ERIC Educational Resources Information Center

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…

Redefining Intersectionality Theory through the Lens of African American Young Adolescent Girls' Racialized Experiences

ERIC Educational Resources Information Center

Harrison, Lisa

2017-01-01

The research presented uses intersectionality theory as a lens to study the racial identity construction of four African American young adolescent girls. The findings suggest that race was largely situated in a Black-White discourse for the girls in the study. When limited information was provided in home, school, and community settings, the…

Forging Paths through Hostile Territory: Intersections of Women's Identities Pursuing Post-Secondary Computing Education

ERIC Educational Resources Information Center

Ratnabalasuriar, Sheruni

2012-01-01

This study explores experiences of women as they pursue post-secondary computing education in various contexts. Using in-depth interviews, the current study employs qualitative methods and draws from an intersectional approach to focus on how the various barriers emerge for women in different types of computing cultures. In-depth interviews with…

The Unequal Burden of Weight Gain: An Intersectional Approach to Understanding Social Disparities in BMI Trajectories from 1986 to 2001/2002

ERIC Educational Resources Information Center

Ailshire, Jennifer A.; House, James S.

2011-01-01

The implications of recent weight gain trends for widening social disparities in body weight in the United States are unclear. Using an intersectional approach to studying inequality, and the longitudinal and nationally representative American's Changing Lives study (1986-2001/2002), we examine social disparities in body mass index trajectories…

Traffic Signal Synchronization in the Saturated High-Density Grid Road Network

PubMed Central

Hu, Xiaojian; Lu, Jian; Wang, Wei; Zhirui, Ye

2015-01-01

Most existing traffic signal synchronization strategies do not perform well in the saturated high-density grid road network (HGRN). Traffic congestion often occurs in the saturated HGRN, and the mobility of the network is difficult to restore. In order to alleviate traffic congestion and to improve traffic efficiency in the network, the study proposes a regional traffic signal synchronization strategy, named the long green and long red (LGLR) traffic signal synchronization strategy. The essence of the strategy is to control the formation and dissipation of queues and to maximize the efficiency of traffic flows at signalized intersections in the saturated HGRN. With this strategy, the same signal control timing plan is used at all signalized intersections in the HGRN, and the straight phase of the control timing plan has a long green time and a long red time. Therefore, continuous traffic flows can be maintained when vehicles travel, and traffic congestion can be alleviated when vehicles stop. Using the strategy, the LGLR traffic signal synchronization model is developed, with the objective of minimizing the number of stops. Finally, the simulation is executed to analyze the performance of the model by comparing it to other models, and the superiority of the LGLR model is evident in terms of delay, number of stops, queue length, and overall performance in the saturated HGRN. PMID:25663835

Guidelines for signal operations at intersections with wide medians.

DOT National Transportation Integrated Search

2010-03-01

The objective of this project is to evaluate the operations at signalized intersections with wide medians in : order to improve safety and efficiency. Intersections with wide medians are characterized by two : intersections and operate differently co...

Self organized spatio-temporal structure within the fractured Vadose Zone: The influence of dynamic overloading at fracture intersections

NASA Astrophysics Data System (ADS)

LaViolette, Randall A.; Glass, Robert J.

2004-09-01

Under low flow conditions (where gravity and capillary forces dominate) within an unsaturated fracture network, fracture intersections act as capillary barriers to integrate flow from above and then release it as a pulse below. Water exiting a fracture intersection is often thought to enter the single connected fracture with the lowest invasion pressure. When the accumulated volume varies between intersections, the smaller volume intersections can be overloaded to cause all of the available fractures exiting an intersection to flow. We included the dynamic overloading process at fracture intersections within our previously discussed model where intersections were modeled as tipping buckets connected within a two-dimensional diamond lattice. With dynamic overloading, the flow behavior transitioned smoothly from diverging to converging flow with increasing overload parameter, as a consequence of a heterogeneous field, and they impose a dynamic structure where additional pathways activate or deactivate in time.

Evasion in the plane

NASA Technical Reports Server (NTRS)

Leitmann, G.; Liu, H. S.

1977-01-01

Dynamic systems were considered subject to control by two agents, one of whom desires that no trajectory of the system emanating from outside a given set, intersects that set no matter what the admissible actions of the other agent. Constructive conditions sufficient to yield a feedback control for the agent seeking avoidance were employed to deduce an evader control for the planar pursuit-evasion problem with bounded normal accelerations.

Evaluation of the dispersion effect in through movement bicycles at signalized intersection via cellular automata simulation

NASA Astrophysics Data System (ADS)

Jiang, Hang; Ma, Yongjian; Jiang, Lin; Chen, Guozhou; Wang, Dongwei

2018-05-01

At signalized intersection areas, bicycle traffic presents a dispersion feature which may influence the movements of vehicles during peak period. The primary objective of this study is to simulate the dispersion effect in through-movement bicycle traffic at intersection areas and evaluate its influence on through-movement traffic. A cellular automata (CA) model is developed and validated to simulate the operations of through-movement bicycle traffic departing from two types of intersection approaches. Simulation results show that bicycles benefit from the dispersion effect when they depart from the approach with an exclusive right-turn vehicle lane. But when bicycles travel from the approach with a shared right-turn and through vehicle lane, the dispersion effect will result in friction interference and block interference on through-movement vehicles. Bicycle interferences reduce the vehicle speed and increase the delay of through-movement vehicles. The policy implications in regard to the dispersion effect from two types of approaches are discussed to improve the performance of through-movement traffic operations at signalized intersections.

(En)gendering Racial Disparities in Health Trajectories: A Life Course and Intersectional Analysis.

PubMed

Richardson, Liana J; Brown, Tyson H

2016-12-01

Historically, intersectionality has been an underutilized framework in sociological research on racial/ethnic and gender inequalities in health. To demonstrate its utility and importance, we conduct an intersectional analysis of the social stratification of health using the exemplar of hypertension-a health condition in which racial/ethnic and gender differences have been well-documented. Previous research has tended to examine these differences separately and ignore how the interaction of social status dimensions may influence health over time. Using seven waves of data from the Health and Retirement Study and multilevel logistic regression models, we found a multiplicative effect of race/ethnicity and gender on hypertension risk trajectories, consistent with both an intersectionality perspective and persistent inequality hypothesis. Group differences in past and contemporaneous socioeconomic and behavioral factors did not explain this effect.

Diversity, social justice, and intersectionality trends in C/MFT: a content analysis of three family therapy journals, 2004-2011.

PubMed

Seedall, Ryan B; Holtrop, Kendal; Parra-Cardona, José Ruben

2014-04-01

In this study, we analyzed the amount of attention given to diversity, social justice, and an intersectional approach to social inequalities over an 8-year period (769 articles) in three family therapy journals. Overall, 28.1% of articles addressed at least one diversity issue, and a social justice framework was utilized in 48.1% of diversity articles. A systemic, intersectional approach to conceptualizing and analyzing multiple social inequalities was utilized in 17.6% of diversity articles. The most common goals addressed in diversity articles, articles using a social justice framework, and articles using an intersectional approach are also identified. Findings indicate that, despite important work being carried out, more work remains to further identify how addressing diversity issues can improve client outcomes. © 2013 American Association for Marriage and Family Therapy.

NORTHEAST FACADE AND ONESTORY WING FROM ENTRY DRIVE, VIEW FACING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

NORTHEAST FACADE AND ONE-STORY WING FROM ENTRY DRIVE, VIEW FACING SOUTHWEST. - Naval Air Station Barbers Point, Control Tower & Aviation Operations Building, Near intersection of runways between Hangar 110 & Building 115, Ewa, Honolulu County, HI

Bicycle and Pedestrian Considerations at Roundabouts

DOT National Transportation Integrated Search

2000-09-01

A roundabout was defined by the Florida Department of Transportation as "any intersection of two or more streets that is designed around a central island." Roundabouts are designed as an effective traffic control measure to resolve conflicts between ...

Signal timing under saturated conditions

DOT National Transportation Integrated Search

2008-11-01

This report provides guidance to practitioners for strategies and tactics that will help mitigate the effects of congestion at traffic signals. The focus was on methods that made use of settings wtihin the local intersection controller rather than on...

Portable Runway Intersection Display and Monitoring System

NASA Technical Reports Server (NTRS)

Elrod, Susan Vinz (Inventor); Dabney, Richard W. (Inventor)

2011-01-01

Systems, methods and apparatus are provided through which an apparatus located on an airfield provides information to pilots in aircraft on the ground and simultaneously gathers information on the motion and position of the aircraft for controllers.

Development of guidelines for the installation of marked crosswalks.

DOT National Transportation Integrated Search

2004-01-01

The Manual on Uniform Traffic Control Devices (MUTCD) provides little guidance on the installation of marked crosswalks, especially at locations other than intersections, i.e., mid-block locations. Crosswalks have typically been installed and designe...

Dynamically SUSY breaking SQCD on F-theory seven-branes

NASA Astrophysics Data System (ADS)

Buchbinder, Evgeny I.

2008-09-01

We study how dynamically breaking SQCD can be obtained on two intersecting seven-branes in F-theory. In the mechanism which we present in this paper one of the seven-branes is responsible for producing the low-energy gauge group and the other one is for generating vector bundle moduli. The fundamental matter charged under the gauge group is localized on the intersection. The mass of the matter fields is controlled by the vector bundle moduli. The analysis of under what conditions a sufficient number of the fundamental flavors becomes light turns out to be equivalent to the analysis of non-perturbative superpotentials for vector bundle moduli in Heterotic M-theory. We give an example in which we present an explicit equation in the moduli space whose zero locus corresponds to the fundamental fields becoming light. This allows us to provide a local F-theory realization of massive Script N = 1, SU(Nc) SQCD in the free magnetic range which dynamically breaks supersymmetry.

Simulation of the effect of a magnetically insulated anode on a low-power cylindrical Hall thruster

NASA Astrophysics Data System (ADS)

Yongjie, DING; Hong, LI; Boyang, JIA; Peng, LI; Liqiu, WEI; Yu, XU; Wuji, PENG; Hezhi, SUN; Yong, CAO; Daren, YU

2018-03-01

The intersection point of the characteristic magnetic field line (CMFL) crossing the anode boundary with the discharge channel wall, and its influence on thruster performance and the energy and flux of ions bombarding the channel wall, have been studied numerically. The simulation results demonstrate that with the increase in distance from the crossover point of the CMFL with the channel wall to the bottom of the thruster channel, the ionization rate in the discharge channel gradually increases; meanwhile, the ion energy and ion current density bombarding the channel wall decreases. When the point of the CMFL with the channel wall is at the channel outlet, the thrust, specific impulse, and efficiency are at a maximum, while the ion energy and ion current density bombarding the channel wall are at a minimum. Therefore, to improve the performance and lifetime of the thruster, it is important to control the point of intersection of the CMFL with the channel wall.

Effects of turning and through lane sharing on traffic performance at intersections

NASA Astrophysics Data System (ADS)

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.

Gendered mental disorders: masculine and feminine stereotypes about mental disorders and their relation to stigma.

PubMed

Boysen, Guy; Ebersole, Ashley; Casner, Robert; Coston, Nykhala

2014-01-01

Research indicates that stereotypes can intersect. For example, the intersection of stereotypes about gender and mental disorders could result in perceptions of gendered mental disorders. In the current research, Studies 1 and 2 showed that people view specific disorders as being masculine or feminine. The masculine stereotype included antisocial personality disorder, addictions, and paraphilias. The feminine stereotype included eating disorders, histrionic personality disorder, body dysmorphia, and orgasmic disorder. In both studies, the perception of disorders as masculine was positively correlated with stigma. Study 3 showed that the positive correlation between masculinity and stigma also occurred when examining specific symptoms rather than full mental disorders. The findings provide further evidence for the intersection of stereotypes and indicate a novel factor in the understanding of stigma.

Privileges and penalties in the legal profession: an intersectional analysis of career progression.

PubMed

Tomlinson, Jennifer; Valizade, Danat; Muzio, Daniel; Charlwood, Andy; Aulakh, Sundeep

2018-04-26

Intersectionality theory is concerned with integrating social characteristics to better understanding complex human relations and inequalities in organizations and societies (McCall ). Recently, intersectionality research has taken a categorical and quantitative turn as scholars critically adopt but retain existing social categories to explain differences in labour market outcomes. A key contention is that social categories carry penalties or privileges and their intersection promotes or hinders the life chances of particular groups and individuals. An emergent debate is whether the intersection of disadvantaged characteristics (such as female gender or minority ethnic status) produce penalties that are additive, multiplicative or ameliorative. Research is inconclusive and as yet pays little attention to moderating factors such as employer type, size, geographic location or work profile. Drawing on administrative records for individuals qualified as solicitors in England and Wales, collected by the Solicitors Regulation Authority (SRA), combined with aggregated workforce data and firm characteristics of their law firms, we undertake a statistical analysis of the intersection of gender and ethnicity in the profession with a degree of precision and nuance not previously possible. In response to calls to broaden studies of inequalities and intersectionality beyond their effect on pay or income (Castilla ) we focus on career progression to partnership as our key measure of success. The original contribution of our study is twofold. First, we establish statistically different profiles of law firms, showing how the solicitors' profession is stratified by gender, ethnicity and socio-economic background, as well as the type of legal work undertaken by developing a model of socio-economic stratification in the profession. Second, we demonstrate that while penalties tend to be additive (i.e. the sum of the individual ethnic and gender penalties) this varies significantly by law firm profile and in some situations the effect is ameliorative. © London School of Economics and Political Science 2018.

Intersectionality: An Arts-Based Approach to Student Awareness

ERIC Educational Resources Information Center

Edmonds, Leonard

2017-01-01

This study was designed to introduce specific activities/lessons to students in an online university gender and communication course. It was also designed to determine how participants made meaning of and felt about learning about intersectionality of gender and cultural identities, using arts-based data collection. Previous research on the…

Dilemma zone protection and signal coordination at closely-spaced high-speed intersections : final report, November 2001.

DOT National Transportation Integrated Search

2001-11-01

A feasibility study of dilemma zone problems, performed by collecting and analyzing traffic flow data at a high-speed signalized intersection, showed that the maximum green extension or cutback needed to get a vehicle out of the dilemma zone is gener...

Operation, analysis, and design of signalized intersections : a module for the introductory course in transportation engineering.

DOT National Transportation Integrated Search

2014-02-01

This report presents materials that can be used as the basis for a module on signalized intersections in the introductory : course in transportation engineering. The materials were developed based on studies of the work of students who took : this in...

Intersectional Identity Negotiation: The Case of Young Immigrant Children

ERIC Educational Resources Information Center

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…

Ethnic, Gender and Class Intersections in British Women's Leadership Experiences

ERIC Educational Resources Information Center

Showunmi, Victoria; Atewologun, Doyin; Bebbington, Diane

2016-01-01

A qualitative study was conducted to examine how gender and ethnicity influenced leadership experiences of a mixed ethnic sample of British women. An intersectional framework was used which took the viewpoint that socio-demographic identities should be considered simultaneously in order to challenge universalist, gender and ethnic neutral…

Guaranteed LiDAR-aided multi-object tracking at road intersections : USDOT Region V Regional University Transportation Center final report.

DOT National Transportation Integrated Search

2016-12-21

The ability to accurately measure and cost-effectively collect traffic data at road intersections is needed to improve their safety and operations. This study investigates the feasibility of using laser ranging technology (LiDAR) for this purpose. Th...

Design and Evaluation of a Dynamic Dilemma Zone System for a High Speed Rural Intersection

DOT National Transportation Integrated Search

2012-08-01

The goal of this research was to develop a system that utilizes the dynamic detection technology and : to evaluate the performance of this system. The first step of this study was to select an intersection : experiencing a high frequency of crashes t...

Evaluation of low-cost intersection countermeasures to reduce red-light-running violations : retro-reflective signal back plates.

DOT National Transportation Integrated Search

2013-11-01

Red light running has become a serious safety issue at signalized intersections throughout the : United States. One objective of this study was to identify the characteristics of red-light-running (RLR) : crashes and the drivers involved in those cra...

Dilemma zone protection and signal coordination at closely-spaced high-speed intersections : executive summary, November 2001.

DOT National Transportation Integrated Search

2001-11-01

A feasibility study of dilemma zone problems, performed by collecting and analyzing traffic flow data at a high-speed signalized intersection, showed that the maximum green extension or cutback needed to get a vehicle out of the dilemma zone is gener...

Complicating Hetero-Femininities: Young Women, Sexualities and "Girl Power" at School

ERIC Educational Resources Information Center

Charles, Claire Elizabeth

2010-01-01

This paper is concerned with expanding knowledge of how femininity/sexuality intersections are constituted in secondary schools. Existing studies have drawn upon Judith Butler's notion of a "heterosexual matrix" in order to understand how intersections of femininity/sexuality are produced in schools through normative discourses of…

Six-Mile Corridor Economic Impact Study, Interstate 44 and Interstate 70 Corridor Summary

DOT National Transportation Integrated Search

2007-08-02

You've come a long way baby: Imagine an 89-percent drop in the number of accidents at your most dangerous intersections; a 100 percent decrease in the number of serious injuries at those same intersections, and 40- plus hours a year trimmed from the ...

Differential arrest and adhesion of tumor cells and microbeads in the microvasculature

PubMed Central

Guo, Peng; Cai, Bin; Lei, Ming; Liu, Yang

2013-01-01

To investigate the mechanical mechanisms behind tumor cell arrest in the microvasculature, we injected fluorescently labeled human breast carcinoma cells or similarly sized rigid beads into the systemic circulation of a rat. Their arrest patterns in the microvasculature of mesentery were recorded and quantified. We found that 93% of rigid beads were arrested either at arteriole–capillary intersections or in capillaries. Only 3% were at the capillary–postcapillary venule intersections and in postcapillary venules. In contrast, most of the flexible tumor cells were either entrapped in capillaries or arrested at capillary or postcapillary venule–postcapillary venule intersections and in postcapillary venules. Only 12% of tumor cells were arrested at the arteriole–capillary intersections. The differential arrest and adhesion of tumor cells and microbeads in the microvasculature was confirmed by a χ2 test (p < 0.001). These results demonstrate that mechanical trapping was responsible for almost all the arrest of beads and half the arrest of tumor cells. Based on the measured geometry and blood flow velocities at the intersections, we also performed a numerical simulation using commercial software (ANSYS CFX 12.01) to depict the detailed distribution profiles of the velocity, shear rate, and vorticity at the intersections where tumor cells preferred to arrest and adhere. Simulation results reveal the presence of localized vorticity and shear rate regions at the turning points of the microvessel intersections, implying that hemodynamic factors play an important role in tumor cell arrest in the microcirculation. Our study helps elucidate long-debated issues related to the dominant factors in early-stage tumor hematogenous metastasis. PMID:23880911

Differential arrest and adhesion of tumor cells and microbeads in the microvasculature.

PubMed

Guo, Peng; Cai, Bin; Lei, Ming; Liu, Yang; Fu, Bingmei M

2014-06-01

To investigate the mechanical mechanisms behind tumor cell arrest in the microvasculature, we injected fluorescently labeled human breast carcinoma cells or similarly sized rigid beads into the systemic circulation of a rat. Their arrest patterns in the microvasculature of mesentery were recorded and quantified. We found that 93% of rigid beads were arrested either at arteriole-capillary intersections or in capillaries. Only 3% were at the capillary-postcapillary venule intersections and in postcapillary venules. In contrast, most of the flexible tumor cells were either entrapped in capillaries or arrested at capillary or postcapillary venule-postcapillary venule intersections and in postcapillary venules. Only 12% of tumor cells were arrested at the arteriole-capillary intersections. The differential arrest and adhesion of tumor cells and microbeads in the microvasculature was confirmed by a χ(2) test (p < 0.001). These results demonstrate that mechanical trapping was responsible for almost all the arrest of beads and half the arrest of tumor cells. Based on the measured geometry and blood flow velocities at the intersections, we also performed a numerical simulation using commercial software (ANSYS CFX 12.01) to depict the detailed distribution profiles of the velocity, shear rate, and vorticity at the intersections where tumor cells preferred to arrest and adhere. Simulation results reveal the presence of localized vorticity and shear rate regions at the turning points of the microvessel intersections, implying that hemodynamic factors play an important role in tumor cell arrest in the microcirculation. Our study helps elucidate long-debated issues related to the dominant factors in early-stage tumor hematogenous metastasis.

Driving with hemianopia: IV. Head scanning and detection at intersections in a simulator.

PubMed

Bowers, Alex R; Ananyev, Egor; Mandel, Aaron J; Goldstein, Robert B; Peli, Eli

2014-03-13

Using a driving simulator, we examined the effects of homonymous hemianopia (HH) on head scanning behaviors at intersections and evaluated the role of inadequate head scanning in detection failures. Fourteen people with complete HH and without cognitive decline or visual neglect and 12 normally sighted (NV) current drivers participated. They drove in an urban environment following predetermined routes, which included multiple intersections. Head scanning behaviors were quantified at T-intersections (n = 32) with a stop or yield sign. Participants also performed a pedestrian detection task. The relationship between head scanning and detection was examined at 10 intersections. For HH drivers, the first scan was more likely to be toward the blind than the seeing hemifield. They also made a greater proportion of head scans overall to the blind side than did the NV drivers to the corresponding side (P = 0.003). However, head scan magnitudes of HH drivers were smaller than those of the NV group (P < 0.001). Drivers with HH had impaired detection of blind-side pedestrians due either to not scanning in the direction of the pedestrian or to an insufficient scan magnitude (left HH detected only 46% and right HH 8% at the extreme left and right of the intersection, respectively). Drivers with HH demonstrated compensatory head scan patterns, but not scan magnitudes. Inadequate scanning resulted in blind-side detection failures, which might place HH drivers at increased risk for collisions at intersections. Scanning training tailored to specific problem areas identified in this study might be beneficial.

Intersection collision avoidance using ITS countermeasures. Task 9, Intersection collision avoidance system performance guidelines

DOT National Transportation Integrated Search

2000-09-01

Phase III of the Intersection Collision Avoidance Using ITS Countermeasures program developed testbed systems, implemented the systems on a vehicle, and performed testing to determine the potential effectiveness of this system in preventing intersect...

Intersecting surface defects and instanton partition functions

DOE PAGES

Pan, Yiwen; Peelaers, Wolfger

2017-07-14

We analyze intersecting surface defects inserted in interacting four-dimensional N = 2 supersymmetric quantum field theories. We employ the realization of a class of such systems as the infrared xed points of renormalization group flows from larger theories, triggered by perturbed Seiberg-Witten monopole-like con gurations, to compute their partition functions. These results are cast into the form of a partition function of 4d/2d/0d coupled systems. In conclusion, our computations provide concrete expressions for the instanton partition function in the presence of intersecting defects and we study the corresponding ADHM model.

Viewing equitable practices through the lens of intersecting identities

NASA Astrophysics Data System (ADS)

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.

Intersecting surface defects and instanton partition functions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pan, Yiwen; Peelaers, Wolfger

We analyze intersecting surface defects inserted in interacting four-dimensional N = 2 supersymmetric quantum field theories. We employ the realization of a class of such systems as the infrared xed points of renormalization group flows from larger theories, triggered by perturbed Seiberg-Witten monopole-like con gurations, to compute their partition functions. These results are cast into the form of a partition function of 4d/2d/0d coupled systems. In conclusion, our computations provide concrete expressions for the instanton partition function in the presence of intersecting defects and we study the corresponding ADHM model.

Hip Hop Culture's OGs: A Narrative Inquiry into the Intersection of Hip Hop Culture, Black Males and Their Schooling Experiences

ERIC Educational Resources Information Center

Buchanan, Ian P.

2013-01-01

Using a critical race lens, this narrative study employs a focus group design to explore the intersections between black males, hip hop culture and schooling experiences. To provide a sociocultural grounding, this study first reviews the research literature around hip hop culture.s sociocultural development and its impact as a culture force that…

Intersection decision support : evaluation of a violation warning system to mitigate straight crossing path collisions.

DOT National Transportation Integrated Search

2006-01-01

This project entailed the design, development, testing, and evaluation of intersection decision support (IDS) systems to address straight crossing path (SCP) intersection crashes. This type of intersection crash is responsible for more than 100,000 c...

NORTHEAST FACADE AND ONESTORY WING FROM PARKING LOT SIDE, VIEW ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

NORTHEAST FACADE AND ONE-STORY WING FROM PARKING LOT SIDE, VIEW FACING SOUTH-SOUTHEAST. - Naval Air Station Barbers Point, Control Tower & Aviation Operations Building, Near intersection of runways between Hangar 110 & Building 115, Ewa, Honolulu County, HI

NORTHEAST FACADE AND ONESTORY WING, VIEW FACING SOUTHSOUTHWEST (with scale ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

NORTHEAST FACADE AND ONE-STORY WING, VIEW FACING SOUTH-SOUTHWEST (with scale stick). - Naval Air Station Barbers Point, Control Tower & Aviation Operations Building, Near intersection of runways between Hangar 110 & Building 115, Ewa, Honolulu County, HI

INTERIOR VIEW OF HALLWAY LOOKING TOWARD LOBBY, SHOWING WINDOW DETAILS, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

INTERIOR VIEW OF HALLWAY LOOKING TOWARD LOBBY, SHOWING WINDOW DETAILS, VIEW FACING WEST-SOUTHWEST. - Naval Air Station Barbers Point, Control Tower & Aviation Operations Building, Near intersection of runways between Hangar 110 & Building 115, Ewa, Honolulu County, HI

Traffic Operations Control For Older Drivers And Pedestrians: Summary Report

DOT National Transportation Integrated Search

1996-07-01

The purpose of this investigation was to determine which intersection operational characteristics could be altered to accommodate age-related changes. Two key drivers issues were examined in order to identify the specific older driver problems and th...

Sealing intersecting vane machines

DOEpatents

Martin, Jedd N.; Chomyszak, Stephen M.

2005-06-07

The invention provides a toroidal intersecting vane machine incorporating intersecting rotors to form primary and secondary chambers whose porting configurations minimize friction and maximize efficiency. Specifically, it is an object of the invention to provide a toroidal intersecting vane machine that greatly reduces the frictional losses through intersecting surfaces without the need for external gearing by modifying the width of one or both tracks at the point of intermeshing. The inventions described herein relate to these improvements.

Sealing intersecting vane machines

DOEpatents

Martin, Jedd N [Providence, RI; Chomyszak, Stephen M [Attleboro, MA

2007-06-05

The invention provides a toroidal intersecting vane machine incorporating intersecting rotors to form primary and secondary chambers whose porting configurations minimize friction and maximize efficiency. Specifically, it is an object of the invention to provide a toroidal intersecting vane machine that greatly reduces the frictional losses through intersecting surfaces without the need for external gearing by modifying the width of one or both tracks at the point of intermeshing. The inventions described herein relate to these improvements.

Justification of the Expediency of Creating Circular Intersections in Modern Cities

NASA Astrophysics Data System (ADS)

Vasilyeva, Elena; Sazonova, Tatiana

2017-10-01

The article resumes the principles of driving on Circular Intersections, which causes difficulties for some road users. Referring to certain foreign Traffic regulations, the author points out that such intersections are still stated imprecisely in Traffic regulations. Advantages and disadvantages of circular intersections as well as the expediency of their creation in the cities are considered in the article. The author offers to distinguish several types of circular intersections and claims that the most part of disadvantages listed in the article belong to circular intersections of the old type. On the contrary, the author presumes that creation of modern circular intersections will allow to regulate the planning of cities, make heavy traffic of transport possible while increasing the traffic safety at the same time, to improve the ecological situation of the city as well as its appearance, to carry out energy saving in the transport infrastructure of the city. All these aims could be feasible due to the creation of modern intersections of the Roundabout type.

Ethnic variation in gender-STEM stereotypes and STEM participation: an intersectional approach.

PubMed

O'Brien, Laurie T; Blodorn, Alison; Adams, Glenn; Garcia, Donna M; Hammer, Elliott

2015-04-01

Stereotypes associating men and masculine traits with science, technology, engineering, and mathematics (STEM) fields are ubiquitous, but the relative strength of these stereotypes varies considerably across cultures. The present research applies an intersectional approach to understanding ethnic variation in gender-STEM stereotypes and STEM participation within an American university context. African American college women participated in STEM majors at higher rates than European American college women (Study 1, Study 2, and Study 4). Furthermore, African American women had weaker implicit gender-STEM stereotypes than European American women (Studies 2-4), and ethnic differences in implicit gender-STEM stereotypes partially mediated ethnic differences in STEM participation (Study 2 and Study 4). Although African American men had weaker implicit gender-STEM stereotypes than European American men (Study 4), ethnic differences between men in STEM participation were generally small (Study 1) or nonsignificant (Study 4). We discuss the implications of an intersectional approach for understanding the relationship between gender and STEM participation. (c) 2015 APA, all rights reserved).

An analysis of urban collisions using an artificial intelligence model.

PubMed

Mussone, L; Ferrari, A; Oneta, M

1999-11-01

Traditional studies on road accidents estimate the effect of variables (such as vehicular flows, road geometry, vehicular characteristics), and the calculation of the number of accidents. A descriptive statistical analysis of the accidents (those used in the model) over the period 1992-1995 is proposed. The paper describes an alternative method based on the use of artificial neural networks (ANN) in order to work out a model that relates to the analysis of vehicular accidents in Milan. The degree of danger of urban intersections using different scenarios is quantified by the ANN model. Methodology is the first result, which allows us to tackle the modelling of urban vehicular accidents by the innovative use of ANN. Other results deal with model outputs: intersection complexity may determine a higher accident index depending on the regulation of intersection. The highest index for running over of pedestrian occurs at non-signalised intersections at night-time.

On classical de Sitter and Minkowski solutions with intersecting branes

NASA Astrophysics Data System (ADS)

Andriot, David

2018-03-01

Motivated by the connection of string theory to cosmology or particle physics, we study solutions of type II supergravities having a four-dimensional de Sitter or Minkowski space-time, with intersecting D p -branes and orientifold O p -planes. Only few such solutions are known, and we aim at a better characterisation. Modulo a few restrictions, we prove that there exists no classical de Sitter solution for any combination of D 3/ O 3 and D 7/ O 7, while we derive interesting constraints for intersecting D 5/ O 5 or D 6/ O 6, or combinations of D 4/ O 4 and D 8/ O 8. Concerning classical Minkowski solutions, we understand some typical features, and propose a solution ansatz. Overall, a central information appears to be the way intersecting D p / O p overlap each other, a point we focus on.

Women's health, men's health, and gender and health: implications of intersectionality.

PubMed

Hankivsky, Olena

2012-06-01

Although intersectionality is now recognized in the context of women's health, men's health, and gender and health, its full implications for research, policy, and practice have not yet been interrogated. This paper investigates, from an intersectionality perspective, the common struggles within each field to confront the complex interplay of factors that shape health inequities. Drawing on developments within intersectionality scholarship and various sources of research and policy evidence (including examples from the field of HIV/AIDS), the paper demonstrates the methodological feasibility of intersectionality and in particular, the wide-ranging benefits of de-centering gender through intersectional analyses. Copyright © 2012 Elsevier Ltd. All rights reserved.

The Intersection Challenge

ERIC Educational Resources Information Center

Roman, Harry T.

2011-01-01

Street intersections are a source of accidents--for both automobiles and pedestrians. This article presents an intersection challenge that allows students to explore some possible ways to change the traditional intersection. In this challenge, teachers open up the boundaries and allow students to redesign their world. The first step is to help…

The Challenges and Triumphs in Addressing Students' Intersectional Identities for Black Culture Centers

ERIC Educational Resources Information Center

Harris, Jessica C.; Patton, Lori D.

2017-01-01

This study examines how directors of Black culture centers (BCCs) address Black students' intersectional identities. We highlight the challenges that directors of BCCs face as they attempt to preserve a race salient agenda, while accounting for other critical facets of students' social identities. Findings explore how directors hold differing…

Constructing Identities at the Intersections: An Autoethnographic Exploration of Multiple Dimensions of Identity

ERIC Educational Resources Information Center

Jones, Susan R.

2009-01-01

The purpose of this article is to present the results of an autoethnographic study designed to investigate the complexities of identity development among a diverse group of eight participants and to use results to explore potential relationships between self-authorship and intersecting identities. Data was collected via personal autoethnographic…

Socioeconomic Impact Analysis Study. Disposal and Reuse of Norton Air Force Base, California

DTIC Science & Technology

1993-06-01

area and on C Street west of Tp •pecanoe. The two busiest intersections on base are signalized; that is, intersection Sixth Street/E Street, and...Ohio Years of Experience: 20 Craig M. Congdon , Environmental Planner, Robert D. Niehaus, Inc. B.S., 1986, Geography/Geology, University of

Suicidality and Intersectionality among Students Identifying as Nonheterosexual and with a Disability

ERIC Educational Resources Information Center

King, Matthew T.; Merrin, Gabriel J.; Espelage, Dorothy L.; Grant, Nickholas J.; Bub, Kristen L.

2018-01-01

Research about students with disabilities and students identifying as LGBQ (lesbian, gay, bisexual, or questioning) reveals that both populations report more suicidality and peer victimization and less school connectedness than do their peers. No study has previously examined the intersection of these identities with regard to peer victimization,…

Voices Unheard: Using Intersectionality to Understand Identity among Sexually Marginalized Undergraduate College Students of Color

ERIC Educational Resources Information Center

Russell, Elizabeth Irene Ann Annie

2012-01-01

This study used intersectionality as a framework and methodology to understand identity among sexually marginalized undergraduate college students of color. The research questions were as follows: (1) What are the experiences of QLGBTSGL (Queer, Lesbian, Gay, Bisexual, Transgender, Same Gender Loving) undergraduate students of color on a college…

Examining the Intersections of Music Making and Teaching for Four String Teachers

ERIC Educational Resources Information Center

Pellegrino, Kristen

2014-01-01

The purpose of this phenomenological case study was to examine the intersections of music making and teaching for four string teachers. Data included background surveys, three interviews per participant, videotaped classroom observations (jointly viewed during the second interview), and a focus group interview that included music making. Findings…

Tuberculosis stigma as a social determinant of health: a systematic mapping review of research in low incidence countries.

PubMed

Craig, G M; Daftary, A; Engel, N; O'Driscoll, S; Ioannaki, A

2017-03-01

Tuberculosis (TB)-related stigma is an important social determinant of health. Research generally highlights how stigma can have a considerable impact on individuals and communities, including delays in seeking health care and adherence to treatment. There is scant research into the assessment of TB-related stigma in low incidence countries. This study aimed to systematically map out the research into stigma. A particular emphasis was placed on the methods employed to measure stigma, the conceptual frameworks used to understand stigma, and whether structural factors were theorized. Twenty-two studies were identified; the majority adopted a qualitative approach and aimed to assess knowledge, attitudes, and beliefs about TB. Few studies included stigma as a substantive topic. Only one study aimed to reduce stigma. A number of studies suggested that TB control measures and representations of migrants in the media reporting of TB were implicated in the production of stigma. The paucity of conceptual models and theories about how the social and structural determinants intersect with stigma was apparent. Future interventions to reduce stigma, and measurements of effectiveness, would benefit from a stronger theoretical underpinning in relation to TB stigma and the intersection between the social and structural determinants of health. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Characterizing Containment and Related Classes of Graphs,

DTIC Science & Technology

1985-01-01

Math . to appear. [G2] Golumbic,. Martin C., D. Rotem and J. Urrutia. "Comparability graphs and intersection graphs" Discrete Math . 43 (1983) 37-40. [G3...intersection classes of graphs" Discrete Math . to appear. [S2] Scheinerman, Edward R. Intersection Classes and Multiple Intersection Parameters of Graphs...graphs and of interval graphs" Canad. Jour. of blath. 16 (1964) 539-548. [G1] Golumbic, Martin C. "Containment graphs: and. intersection graphs" Discrete

Wind Tunnel Measurement of Turbulent and Advective Scalar Fluxes: A Case Study on Intersection Ventilation

PubMed Central

Kukačka, Libor; Nosek, Štĕpán; Kellnerová, Radka; Jurčáková, Klára; Jaňour, Zbyněk

2012-01-01

The objective of this study is to determine processes of pollution ventilation in the X-shaped street intersection in an idealized symmetric urban area for the changing approach flow direction. A unique experimental setup for simultaneous wind tunnel measurement of the flow velocity and the tracer gas concentration in a high temporal resolution is assembled. Advective horizontal and vertical scalar fluxes are computed from averaged measured velocity and concentration data within the street intersection. Vertical advective and turbulent scalar fluxes are computed from synchronized velocity and concentration signals measured in the plane above the intersection. All the results are obtained for five approach flow directions. The influence of the approach flow on the advective and turbulent fluxes is determined. The contribution of the advective and turbulent flux to the ventilation is discussed. Wind direction with the best dispersive conditions in the area is found. The quadrant analysis is applied to the synchronized signals of velocity and concentration fluctuation to determine events with the dominant contribution to the momentum flux and turbulent scalar flux. PMID:22649290

Wind tunnel measurement of turbulent and advective scalar fluxes: a case study on intersection ventilation.

PubMed

Kukačka, Libor; Nosek, Štĕpán; Kellnerová, Radka; Jurčáková, Klára; Jaňour, Zbyněk

2012-01-01

The objective of this study is to determine processes of pollution ventilation in the X-shaped street intersection in an idealized symmetric urban area for the changing approach flow direction. A unique experimental setup for simultaneous wind tunnel measurement of the flow velocity and the tracer gas concentration in a high temporal resolution is assembled. Advective horizontal and vertical scalar fluxes are computed from averaged measured velocity and concentration data within the street intersection. Vertical advective and turbulent scalar fluxes are computed from synchronized velocity and concentration signals measured in the plane above the intersection. All the results are obtained for five approach flow directions. The influence of the approach flow on the advective and turbulent fluxes is determined. The contribution of the advective and turbulent flux to the ventilation is discussed. Wind direction with the best dispersive conditions in the area is found. The quadrant analysis is applied to the synchronized signals of velocity and concentration fluctuation to determine events with the dominant contribution to the momentum flux and turbulent scalar flux.

Novel Intersection Type Recognition for Autonomous Vehicles Using a Multi-Layer Laser Scanner.

PubMed

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.

Novel Intersection Type Recognition for Autonomous Vehicles Using a Multi-Layer Laser Scanner

PubMed Central

An, Jhonghyun; Choi, Baehoon; Sim, Kwee-Bo; Kim, Euntai

2016-01-01

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. PMID:27447640

30 CFR 56.7055 - Intersecting holes.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Intersecting holes. 56.7055 Section 56.7055... Piercing Drilling § 56.7055 Intersecting holes. Holes shall not be drilled where there is a danger of intersecting a misfired hole or a hole containing explosives blasting agents, or detonators. [56 FR 46508, Sept...

30 CFR 56.7055 - Intersecting holes.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Intersecting holes. 56.7055 Section 56.7055... Piercing Drilling § 56.7055 Intersecting holes. Holes shall not be drilled where there is a danger of intersecting a misfired hole or a hole containing explosives blasting agents, or detonators. [56 FR 46508, Sept...

30 CFR 57.7055 - Intersecting holes.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Intersecting holes. 57.7055 Section 57.7055... Jet Piercing Drilling-Surface and Underground § 57.7055 Intersecting holes. Holes shall not be drilled where there is a danger of intersecting a misfired hole or a hole containing explosives, blasting agents...

30 CFR 57.7055 - Intersecting holes.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Intersecting holes. 57.7055 Section 57.7055... Jet Piercing Drilling-Surface and Underground § 57.7055 Intersecting holes. Holes shall not be drilled where there is a danger of intersecting a misfired hole or a hole containing explosives, blasting agents...

30 CFR 56.7055 - Intersecting holes.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Intersecting holes. 56.7055 Section 56.7055... Piercing Drilling § 56.7055 Intersecting holes. Holes shall not be drilled where there is a danger of intersecting a misfired hole or a hole containing explosives blasting agents, or detonators. [56 FR 46508, Sept...

30 CFR 57.7055 - Intersecting holes.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Intersecting holes. 57.7055 Section 57.7055... Jet Piercing Drilling-Surface and Underground § 57.7055 Intersecting holes. Holes shall not be drilled where there is a danger of intersecting a misfired hole or a hole containing explosives, blasting agents...

30 CFR 57.7055 - Intersecting holes.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Intersecting holes. 57.7055 Section 57.7055... Jet Piercing Drilling-Surface and Underground § 57.7055 Intersecting holes. Holes shall not be drilled where there is a danger of intersecting a misfired hole or a hole containing explosives, blasting agents...

30 CFR 56.7055 - Intersecting holes.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Intersecting holes. 56.7055 Section 56.7055... Piercing Drilling § 56.7055 Intersecting holes. Holes shall not be drilled where there is a danger of intersecting a misfired hole or a hole containing explosives blasting agents, or detonators. [56 FR 46508, Sept...

30 CFR 57.7055 - Intersecting holes.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Intersecting holes. 57.7055 Section 57.7055... Jet Piercing Drilling-Surface and Underground § 57.7055 Intersecting holes. Holes shall not be drilled where there is a danger of intersecting a misfired hole or a hole containing explosives, blasting agents...

30 CFR 56.7055 - Intersecting holes.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Intersecting holes. 56.7055 Section 56.7055... Piercing Drilling § 56.7055 Intersecting holes. Holes shall not be drilled where there is a danger of intersecting a misfired hole or a hole containing explosives blasting agents, or detonators. [56 FR 46508, Sept...

INTERIOR SHOWING STAIRCASE TO SECOND FLOOR FROM MAIN LOBBY/RECEPTION AREA, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

INTERIOR SHOWING STAIRCASE TO SECOND FLOOR FROM MAIN LOBBY/RECEPTION AREA, VIEW FACING WEST-SOUTHWEST. - Naval Air Station Barbers Point, Control Tower & Aviation Operations Building, Near intersection of runways between Hangar 110 & Building 115, Ewa, Honolulu County, HI

State of the art in the management of through traffic in residential subdivisions.

DOT National Transportation Integrated Search

1977-01-01

Through traffic in residential subdivisions results from motorists seeking shortcuts between two arterial roads, or trying to avoid saturated intersections of two arterial roads. Control techniques to reduce through traffic could be classified into i...

PIA installation and user guide : 2009 update.

DOT National Transportation Integrated Search

2010-04-01

A significant number of TxDOTs signalized intersections operate under isolated control. : At many of these signals, it is not uncommon for an approaching platoon of vehicles to : face a red signal when it arrives at the stopbar. Often, these plato...

Recording devices for interconnected grade crossing and intersection signal systems : an informational report.

DOT National Transportation Integrated Search

2012-10-01

Over 15 years ago, the National Transportation Safety Board (NTSB) issued 29 recommendations : to improve safety at active controlled highway-rail grade crossings following the school buscommuter : train collision in Fox River Grove, Illinois. The ob...

Paving the Way for Greener Highways : Extending Concrete's Service Life Through Multiscale Crack Control

DOT National Transportation Integrated Search

2013-10-21

Today many intersections are operated based on data input from nonintrusive video detection systems. With those systems the video detectors can be easily deployed/modified for different application requirements. This research project is initiated to ...

Addressing dilemma zone issues with control solutions : final report.

DOT National Transportation Integrated Search

2017-04-01

Rural, high-speed signalized intersections are associated with vehicle crashes attributable to problems in dilemma zones : (DZs). DZs are areas where at the onset of yellow, some drivers may decide to proceed and some may decide to stop. This : disag...

Improved traffic control measures to prevent incorrect turns at highway-rail grade crossings.

DOT National Transportation Integrated Search

2013-11-01

A number of injuries and fatal collisions have occurred at certain highway-rail grade crossings that are located immediately adjacent to highway intersections, driveways or interstate ramps. Some guide signage, pavement markings, and other traffic co...

State-of-the-art literature review on permissive/protected left-turn control.

DOT National Transportation Integrated Search

2013-06-01

In spring 2010, the Illinois Department of Transportation initiated an areawide implementation to integrate the : flashing yellow arrow as the display for the left-turn permissive interval at more than 100 intersections operating : with protected/per...

Comparison of proposed countermeasures for dilemma zone at signalized intersections based on cellular automata simulations.

PubMed

Wu, Yina; Abdel-Aty, Mohamed; Ding, Yaoxian; Jia, Bin; Shi, Qi; Yan, Xuedong

2018-07-01

The Type II dilemma zone describes the road segment to a signalized intersection where drivers have difficulties to decide either stop or go at the onset of yellow signal. Such phenomenon can result in an increased crash risk at signalized intersections. Different types of warning systems have been proposed to help drivers make decisions. Although the warning systems help to improve drivers' behavior, they also have several disadvantages such as increasing rear-end crashes or red-light running (RLR) violations. In this study, a new warning system called pavement marking with auxiliary countermeasure (PMAIC) is proposed to reduce the dilemma zone and enhance the traffic safety at signalized intersections. The proposed warning system integrates the pavement marking and flashing yellow system which can provide drivers with better suggestions about stop/go decisions based on their arriving time and speed. In order to evaluate the performance of the proposed warning system, this paper presents a cellular automata (CA) simulation study. The CA simulations are conducted for four different scenarios in total, including the typical intersection without warning system, the intersection with flashing green countermeasure, the intersection with pavement marking, and the intersection with the PMAIC warning system. Before the specific CA simulation analysis, a logistic regression model is calibrated based on field video data to predict drivers' general stop/go decisions. Also, the rules of vehicle movements in the CA models under the influence by different warning systems are proposed. The proxy indicators of rear-end crash and potential RLR violations were estimated and used to evaluate safety levels for the different scenarios. The simulation results showed that the PMAIC countermeasure consistently offered best performance to reduce rear-end crash and RLR violation. Meanwhile, the results indicate that the flashing-green countermeasure could not effectively reduce either rear-end crash risk or RLR violations. Also, it is found that the pavement-marking countermeasure has positive effects on reducing the rear-end risk while it may increase the probability of RLR violation. Lastly, the implementation of the proposed warning system is discussed with the consideration of connected-vehicle technology. It is expected that the dilemma zone issues can be efficiently addressed if the proposed countermeasure can be employed within connected vehicle technology. Copyright © 2017 Elsevier Ltd. All rights reserved.

Matching shapes with self-intersections: application to leaf classification.

PubMed

Mokhtarian, Farzin; Abbasi, Sadegh

2004-05-01

We address the problem of two-dimensional (2-D) shape representation and matching in presence of self-intersection for large image databases. This may occur when part of an object is hidden behind another part and results in a darker section in the gray level image of the object. The boundary contour of the object must include the boundary of this part which is entirely inside the outline of the object. The Curvature Scale Space (CSS) image of a shape is a multiscale organization of its inflection points as it is smoothed. The CSS-based shape representation method has been selected for MPEG-7 standardization. We study the effects of contour self-intersection on the Curvature Scale Space image. When there is no self-intersection, the CSS image contains several arch shape contours, each related to a concavity or a convexity of the shape. Self intersections create contours with minima as well as maxima in the CSS image. An efficient shape representation method has been introduced in this paper which describes a shape using the maxima as well as the minima of its CSS contours. This is a natural generalization of the conventional method which only includes the maxima of the CSS image contours. The conventional matching algorithm has also been modified to accommodate the new information about the minima. The method has been successfully used in a real world application to find, for an unknown leaf, similar classes from a database of classified leaf images representing different varieties of chrysanthemum. For many classes of leaves, self-intersection is inevitable during the scanning of the image. Therefore the original contributions of this paper is the generalization of the Curvature Scale Space representation to the class of 2-D contours with self-intersection, and its application to the classification of Chrysanthemum leaves.

Comparison of intersecting pedestrian flows based on experiments

NASA Astrophysics Data System (ADS)

Zhang, J.; Seyfried, A.

2014-07-01

Intersections of pedestrian flows feature multiple types, varying in the numbers of flow directions as well as intersecting angles. In this article results from intersecting flow experiments with two different intersecting angles are compared. To analyze the transport capabilities the Voronoi method is used to resolve the fine structure of the resulting velocity-density relations and spatial dependence of the measurements. The fundamental diagrams of various flow types are compared and show no apparent difference with respect to the intersecting angle 90° and 180°. This result indicates that head-on conflicts of different types of flow have the same influence on the transport properties of the system, which demonstrates the high self-organization capabilities of pedestrians.

Analytical Investigation of Elastic Thin-Walled Cylinder and Truncated Cone Shell Intersection Under Internal Pressure.

PubMed

Zamani, J; Soltani, B; Aghaei, M

2014-10-01

An elastic solution of cylinder-truncated cone shell intersection under internal pressure is presented. The edge solution theory that has been used in this study takes bending moments and shearing forces into account in the thin-walled shell of revolution element. The general solution of the cone equations is based on power series method. The effect of cone apex angle on the stress distribution in conical and cylindrical parts of structure is investigated. In addition, the effect of the intersection and boundary locations on the circumferential and longitudinal stresses is evaluated and it is shown that how quantitatively they are essential.

Finite temperature corrections to tachyon mass in intersecting D-branes

NASA Astrophysics Data System (ADS)

Sethi, Varun; Chowdhury, Sudipto Paul; Sarkar, Swarnendu

2017-04-01

We continue with the analysis of finite temperature corrections to the Tachyon mass in intersecting branes which was initiated in [1]. 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 [2]. 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 [1] as well as those for intersecting D2 branes.

Judging arrival times of incoming traffic vehicles is not a prerequisite for safely crossing an intersection: Differential effects of vehicle size and type in passive judgment and active driving tasks.

PubMed

Mathieu, Julie; Bootsma, Reinoud J; Berthelon, Catherine; Montagne, Gilles

2017-02-01

Using a fixed-base driving simulator we compared the effects of the size and type of traffic vehicles (i.e., normal-sized or double-sized cars or motorcycles) approaching an intersection in two different tasks. In the perceptual judgment task, passively moving participants estimated when a traffic vehicle would reach the intersection for actual arrival times (ATs) of 1, 2, or 3s. In line with earlier findings, ATs were generally underestimated, the more so the longer the actual AT. Results revealed that vehicle size affected judgments in particular for the larger actual ATs (2 and 3s), with double-sized vehicles then being judged as arriving earlier than normal-sized vehicles. Vehicle type, on the other hand, affected judgments at the smaller actual ATs (1 and 2s), with cars then being judged as arriving earlier than motorcycles. In the behavioral task participants actively drove the simulator to cross the intersection by passing through a gap in a train of traffic. Analyses of the speed variations observed during the active intersection-crossing task revealed that the size and type of vehicles in the traffic train did not affect driving behavior in the same way as in the AT judgment task. First, effects were considerably smaller, affecting driving behavior only marginally. Second, effects were opposite to expectations based on AT judgments: driver approach speeds were smaller (rather than larger) when confronted with double-sized vehicles as compared to their normal-sized counterparts and when confronted with cars as compared to motorcycles. Finally, the temporality of the effects was different on the two tasks: vehicle size affected driver approach speed in the final stages of approach rather than early on, while vehicle type affected driver approach speed early on rather than later. Overall, we conclude that the active control of approach to the intersection is not based on successive judgments of traffic vehicle arrival times. These results thereby question the general belief that arrival time estimates are crucial for safe interaction with traffic. Copyright © 2016 Elsevier B.V. All rights reserved.

The design of a minimal sensor configuration for a Cooperative Intersection Collision Avoidance System - Stop Sign Assist : (CICAS-SSA report #2).

DOT National Transportation Integrated Search

2010-08-01

The deployment of a Cooperative Intersection Collision Avoidance System Stop Sign Assist (CICAS-SSA) can save lives by addressing the causal factor of crashes at rural thru-Stop intersection: drivers who stop on the minor leg of the intersection,...

Intersection of three-dimensional geometric surfaces

NASA Technical Reports Server (NTRS)

Crisp, V. K.; Rehder, J. J.; Schwing, J. L.

1985-01-01

Calculating the line of intersection between two three-dimensional objects and using the information to generate a third object is a key element in a geometry development system. Techniques are presented for the generation of three-dimensional objects, the calculation of a line of intersection between two objects, and the construction of a resultant third object. The objects are closed surfaces consisting of adjacent bicubic parametric patches using Bezier basis functions. The intersection determination involves subdividing the patches that make up the objects until they are approximately planar and then calculating the intersection between planes. The resulting straight-line segments are connected to form the curve of intersection. The polygons in the neighborhood of the intersection are reconstructed and put back into the Bezier representation. A third object can be generated using various combinations of the original two. Several examples are presented. Special cases and problems were encountered, and the method for handling them is discussed. The special cases and problems included intersection of patch edges, gaps between adjacent patches because of unequal subdivision, holes, or islands within patches, and computer round-off error.

Changes in crash risk following re-timing of traffic signal change intervals.

PubMed

Retting, Richard A; Chapline, Janella F; Williams, Allan F

2002-03-01

More than I million motor vehicle crashes occur annually at signalized intersections in the USA. The principal method used to prevent crashes associated with routine changes in signal indications is employment of a traffic signal change interval--a brief yellow and all-red period that follows the green indication. No universal practice exists for selecting the duration of change intervals, and little is known about the influence of the duration of the change interval on crash risk. The purpose of this study was to estimate potential crash effects of modifying the duration of traffic signal change intervals to conform with values associated with a proposed recommended practice published by the Institute of Transportation Engineers. A sample of 122 intersections was identified and randomly assigned to experimental and control groups. Of 51 eligible experimental sites, 40 (78%) needed signal timing changes. For the 3-year period following implementation of signal timing changes, there was an 8% reduction in reportable crashes at experimental sites relative to those occurring at control sites (P = 0.08). For injury crashes, a 12% reduction at experimental sites relative to those occurring at control sites was found (P = 0.03). Pedestrian and bicycle crashes at experimental sites decreased 37% (P = 0.03) relative to controls. Given these results and the relatively low cost of re-timing traffic signals, modifying the duration of traffic signal change intervals to conform with values associated with the Institute of Transportation Engineers' proposed recommended practice should be strongly considered by transportation agencies to reduce the frequency of urban motor vehicle crashes.

Intersections: A Professional Development Project in Multicultural and Global Education, Asian and Asian American Studies.

ERIC Educational Resources Information Center

Swartz, Leslie, Ed.; Warner, Linda, Ed.; Grossman, David L., Ed.

This publication presents a sampling of the writings of participants in the Intersections Project, a professional development program to bridge gap between multicultural and global education for urban schools that involved four participating entities, each with a local project that focused on Asia and Asian Americans. The project was specifically…

Interdisciplinary Research at the Intersection of CALL, NLP, and SLA: Methodological Implications from an Input Enhancement Project

ERIC Educational Resources Information Center

Ziegler, Nicole; Meurers, Detmar; Rebuschat, Patrick; Ruiz, Simón; Moreno-Vega, José L.; Chinkina, Maria; Li, Wenjing; Grey, Sarah

2017-01-01

Despite the promise of research conducted at the intersection of computer-assisted language learning (CALL), natural language processing, and second language acquisition, few studies have explored the potential benefits of using intelligent CALL systems to deepen our understanding of the process and products of second language (L2) learning. The…

Towards a Theory of Distributed Instruction in Creative Arts Education

ERIC Educational Resources Information Center

Rosenfeld Halverson, Erica; Lowenhaupt, Rebecca; Kalaitzidis, T. J.

2015-01-01

This article examines how arts-based informal learning spaces engage young people at the intersection of creativity and technology. We conducted case studies of four youth media arts organizations to understand how teaching is defined and realized in these contexts. We find that teaching is a distributed act that sits at the intersection of…

Tough or Tender: (Dis)Similarities in White College Students' Perceptions of Black and White Women

ERIC Educational Resources Information Center

Donovan, Roxanne A.

2011-01-01

Although intersectional theory and empirical evidence suggest that race impacts how women are perceived, there is a dearth of research on how the dominant culture stereotypes Black women compared to White women. The current study addresses this gap using an intersectional framework to investigate White college students' stereotypes of Black and…

Lost in the Margins? Intersections between Disability and Other Nondominant Statuses with Regard to Peer Victimization

ERIC Educational Resources Information Center

McGee, Marjorie G.

2014-01-01

This study examined the extent to which disability status, alone and in combination with other social identities, was associated with differential levels of exposure to peer victimization. Logistic analyses of survey responses from eleventh graders completing the 2008 Oregon Healthy Teen survey (N = 7,091) utilized an intersectional,…

Video library for video imaging detection at intersection stop lines.

DOT National Transportation Integrated Search

2010-04-01

The objective of this activity was to record video that could be used for controlled : evaluation of video image vehicle detection system (VIVDS) products and software upgrades to : existing products based on a list of conditions that might be diffic...

Assessing the risk of crash for trucks on onset yellow.

DOT National Transportation Integrated Search

2012-06-01

Each day, millions of signal changes to the yellow phase occur at isolated high speed intersections, when erroneous : driver decisions to stop or go may often lead to a crash. Dilemma zone protection systems are typically used to control : these inte...

A Field and Simulator Evaluation of All-Red Clearance Intervals for Use in Left-Turn Applications

DOT National Transportation Integrated Search

2018-03-01

As the implementation of the novel flashing yellow arrow (FYA) traffic control device advances throughout the country, agencies continually seek ways to improve intersection operations and safety, especially on left turns. For example, permissive lef...

Study on robot motion control for intelligent welding processes based on the laser tracking sensor

NASA Astrophysics Data System (ADS)

Zhang, Bin; Wang, Qian; Tang, Chen; Wang, Ju

2017-06-01

A robot motion control method is presented for intelligent welding processes of complex spatial free-form curve seams based on the laser tracking sensor. First, calculate the tip position of the welding torch according to the velocity of the torch and the seam trajectory detected by the sensor. Then, search the optimal pose of the torch under constraints using genetic algorithms. As a result, the intersection point of the weld seam and the laser plane of the sensor is within the detectable range of the sensor. Meanwhile, the angle between the axis of the welding torch and the tangent of the weld seam meets the requirements. The feasibility of the control method is proved by simulation.

Control of chemical dynamics by lasers: theoretical considerations.

PubMed

Kondorskiy, Alexey; Nanbu, Shinkoh; Teranishi, Yoshiaki; Nakamura, Hiroki

2010-06-03

Theoretical ideas are proposed for laser control of chemical dynamics. There are the following three elementary processes in chemical dynamics: (i) motion of the wave packet on a single adiabatic potential energy surface, (ii) excitation/de-excitation or pump/dump of wave packet, and (iii) nonadiabatic transitions at conical intersections of potential energy surfaces. A variety of chemical dynamics can be controlled, if we can control these three elementary processes as we desire. For (i) we have formulated the semiclassical guided optimal control theory, which can be applied to multidimensional real systems. The quadratic or periodic frequency chirping method can achieve process (ii) with high efficiency close to 100%. Concerning process (iii) mentioned above, the directed momentum method, in which a predetermined momentum vector is given to the initial wave packet, makes it possible to enhance the desired transitions at conical intersections. In addition to these three processes, the intriguing phenomenon of complete reflection in the nonadiabatic-tunneling-type of potential curve crossing can also be used to control a certain class of chemical dynamics. The basic ideas and theoretical formulations are provided for the above-mentioned processes. To demonstrate the effectiveness of these controlling methods, numerical examples are shown by taking the following processes: (a) vibrational photoisomerization of HCN, (b) selective and complete excitation of the fine structure levels of K and Cs atoms, (c) photoconversion of cyclohexadiene to hexatriene, and (d) photodissociation of OHCl to O + HCl.

Changes in Drivers’ Visual Performance during the Collision Avoidance Process as a Function of Different Field of Views at Intersections

PubMed Central

Yan, Xuedong; Zhang, Xinran; Zhang, Yuting; Li, Xiaomeng; Yang, Zhuo

2016-01-01

The intersection field of view (IFOV) indicates an extent that the visual information can be observed by drivers. It has been found that further enhancing IFOV can significantly improve emergent collision avoidance performance at intersections, such as faster brake reaction time, smaller deceleration rate, and lower traffic crash involvement risk. However, it is not known how IFOV affects drivers’ eye movements, visual attention and the relationship between visual searching and traffic safety. In this study, a driving simulation experiment was conducted to uncover the changes in drivers’ visual performance during the collision avoidance process as a function of different field of views at an intersection by using an eye tracking system. The experimental results showed that drivers’ ability in identifying the potential hazard in terms of visual searching was significantly affected by different IFOV conditions. As the IFOVs increased, drivers had longer gaze duration (GD) and more number of gazes (NG) in the intersection surrounding areas and paid more visual attention to capture critical visual information on the emerging conflict vehicle, thus leading to a better collision avoidance performance and a lower crash risk. It was also found that female drivers had a better visual performance and a lower crash rate than male drivers. From the perspective of drivers’ visual performance, the results strengthened the evidence that further increasing intersection sight distance standards should be encouraged for enhancing traffic safety. PMID:27716824

A robust and efficient polyhedron subdivision and intersection algorithm for three-dimensional MMALE remapping

NASA Astrophysics Data System (ADS)

Chen, Xiang; Zhang, Xiong; Jia, Zupeng

2017-06-01

The Multi-Material Arbitrary Lagrangian Eulerian (MMALE) method is an effective way to simulate the multi-material flow with severe surface deformation. Comparing with the traditional Arbitrary Lagrangian Eulerian (ALE) method, the MMALE method allows for multiple materials in a single cell which overcomes the difficulties in grid refinement process. In recent decades, many researches have been conducted for the Lagrangian, rezoning and surface reconstruction phases, but less attention has been paid to the multi-material remapping phase especially for the three-dimensional problems due to two complex geometric problems: the polyhedron subdivision and the polyhedron intersection. In this paper, we propose a ;Clipping and Projecting; algorithm for polyhedron intersection whose basic idea comes from the commonly used method by Grandy (1999) [29] and Jia et al. (2013) [34]. Our new algorithm solves the geometric problem by an incremental modification of the topology based on segment-plane intersections. A comparison with Jia et al. (2013) [34] shows our new method improves the efficiency by 55% to 65% when calculating polyhedron intersections. Moreover, the instability caused by the geometric degeneracy can be thoroughly avoided because the geometry integrity is preserved in the new algorithm. We also focus on the polyhedron subdivision process and describe an algorithm which could automatically and precisely tackle the various situations including convex, non-convex and multiple subdivisions. Numerical studies indicate that by using our polyhedron subdivision and intersection algorithm, the volume conversation of the remapping phase can be exactly preserved in the MMALE simulation.

Numerical Experiments on Advective Transport in Large Three-Dimensional Discrete Fracture Networks

NASA Astrophysics Data System (ADS)

Makedonska, N.; Painter, S. L.; Karra, S.; Gable, C. W.

2013-12-01

Modeling of flow and solute transport in discrete fracture networks is an important approach for understanding the migration of contaminants in impermeable hard rocks such as granite, where fractures provide dominant flow and transport pathways. The discrete fracture network (DFN) model attempts to mimic discrete pathways for fluid flow through a fractured low-permeable rock mass, and may be combined with particle tracking simulations to address solute transport. However, experience has shown that it is challenging to obtain accurate transport results in three-dimensional DFNs because of the high computational burden and difficulty in constructing a high-quality unstructured computational mesh on simulated fractures. An integrated DFN meshing [1], flow, and particle tracking [2] simulation capability that enables accurate flow and particle tracking simulation on large DFNs has recently been developed. The new capability has been used in numerical experiments on advective transport in large DFNs with tens of thousands of fractures and millions of computational cells. The modeling procedure starts from the fracture network generation using a stochastic model derived from site data. A high-quality computational mesh is then generated [1]. Flow is then solved using the highly parallel PFLOTRAN [3] code. PFLOTRAN uses the finite volume approach, which is locally mass conserving and thus eliminates mass balance problems during particle tracking. The flow solver provides the scalar fluxes on each control volume face. From the obtained fluxes the Darcy velocity is reconstructed for each node in the network [4]. Velocities can then be continuously interpolated to any point in the domain of interest, thus enabling random walk particle tracking. In order to describe the flow field on fractures intersections, the control volume cells on intersections are split into four planar polygons, where each polygon corresponds to a piece of a fracture near the intersection line. Thus, computational nodes lying on fracture intersections have four associated velocities, one on each side of the intersection in each fracture plane [2]. This information is used to route particles arriving at the fracture intersection to the appropriate downstream fracture segment. Verified for small DFNs, the new simulation capability allows accurate particle tracking on more realistic representations of fractured rock sites. In the current work we focus on travel time statistics and spatial dispersion and show numerical results in DFNs of different sizes, fracture densities, and transmissivity distributions. [1] Hyman J.D., Gable C.W., Painter S.L., Automated meshing of stochastically generated discrete fracture networks, Abstract H33G-1403, 2011 AGU, San Francisco, CA, 5-9 Dec. [2] N. Makedonska, S. L. Painter, T.-L. Hsieh, Q.M. Bui, and C. W. Gable., Development and verification of a new particle tracking capability for modeling radionuclide transport in discrete fracture networks, Abstract, 2013 IHLRWM, Albuquerque, NM, Apr. 28 - May 3. [3] Lichtner, P.C., Hammond, G.E., Bisht, G., Karra, S., Mills, R.T., and Kumar, J. (2013) PFLOTRAN User's Manual: A Massively Parallel Reactive Flow Code. [4] Painter S.L., Gable C.W., Kelkar S., Pathline tracing on fully unstructured control-volume grids, Computational Geosciences, 16 (4), 2012, 1125-1134.

Intersections of a Circle and a Square: An Investigation

ERIC Educational Resources Information Center

Canada, Dan; Blair, Stephen

2007-01-01

The investigation of how a circle and square lying in the same plane could intersect each other is an excellent example of geometric problem-solving. This paper explores three facets of the investigation: (1) finding out how many points of intersection are possible, (2) classifying the different ways of intersection, and (3) determining which ways…

Dissipative dynamics at conical intersections: simulations with the hierarchy equations of motion method.

PubMed

Chen, Lipeng; Gelin, Maxim F; Chernyak, Vladimir Y; Domcke, Wolfgang; Zhao, Yang

2016-12-16

The effect of a dissipative environment on the ultrafast nonadiabatic dynamics at conical intersections is analyzed for a two-state two-mode model chosen to represent the S 2 (ππ*)-S 1 (nπ*) conical intersection in pyrazine (the system) which is bilinearly coupled to infinitely many harmonic oscillators in thermal equilibrium (the bath). The system-bath coupling is modeled by the Drude spectral function. The equation of motion for the reduced density matrix of the system is solved numerically exactly with the hierarchy equation of motion method using graphics-processor-unit (GPU) technology. The simulations are valid for arbitrary strength of the system-bath coupling and arbitrary bath memory relaxation time. The present computational studies overcome the limitations of weak system-bath coupling and short memory relaxation time inherent in previous simulations based on multi-level Redfield theory [A. Kühl and W. Domcke, J. Chem. Phys. 2002, 116, 263]. Time evolutions of electronic state populations and time-dependent reduced probability densities of the coupling and tuning modes of the conical intersection have been obtained. It is found that even weak coupling to the bath effectively suppresses the irregular fluctuations of the electronic populations of the isolated two-mode conical intersection. While the population of the upper adiabatic electronic state (S 2 ) is very efficiently quenched by the system-bath coupling, the population of the diabatic ππ* electronic state exhibits long-lived oscillations driven by coherent motion of the tuning mode. Counterintuitively, the coupling to the bath can lead to an enhanced lifetime of the coherence of the tuning mode as a result of effective damping of the highly excited coupling mode, which reduces the strong mode-mode coupling inherent to the conical intersection. The present results extend previous studies of the dissipative dynamics at conical intersections to the nonperturbative regime of system-bath coupling. They pave the way for future first-principles simulations of femtosecond time-resolved four-wave-mixing spectra of chromophores in condensed phases which are nonperturbative in the system dynamics, the system-bath coupling as well as the field-matter coupling.

Exploring the Intersectionality of Bisexual, Religious/Spiritual, and Political Identities from a Feminist Perspective

PubMed Central

Rodriguez, Eric M.; Lytle, Megan C.; Vaughan, Michelle D.

2014-01-01

While there is a small but growing body of work that examines the religious and spiritual lives of bisexuals, there is a strong need for additional research that further explores the intersectionality of these distinct identities. Motivated by the feminist notions that the personal is political and that individuals are the experts of their own experiences (Unger, 2001), the specific aim of this study is to better understand the intersection of multiple identities experienced by bisexual individuals. Relying upon data collected by Herek, Glunt, and colleagues during their Northern California Health Study, in this exploratory study we examine the intersection of bisexual, religious/spiritual, and political identities by conducting an archival secondary analysis of 120 self-identified bisexual individuals. Among the significant findings, results suggest that higher LGB self-esteem scores and openness about sexual orientation correlated with higher levels of spirituality. Further, attraction to same sex partners was associated with perceiving sexual orientation as a choice, identifying as bisexual at a younger age, more likely to disclose one's sexual orientation, less likely to view religion as being socially important, and a higher score on the belief statement. We discuss the implications of these results and make suggestions for future research on the role of religion and spirituality in bisexual lives. PMID:25477767

Exploring the Intersectionality of Bisexual, Religious/Spiritual, and Political Identities from a Feminist Perspective.

PubMed

Rodriguez, Eric M; Lytle, Megan C; Vaughan, Michelle D

2013-07-01

While there is a small but growing body of work that examines the religious and spiritual lives of bisexuals, there is a strong need for additional research that further explores the intersectionality of these distinct identities. Motivated by the feminist notions that the personal is political and that individuals are the experts of their own experiences (Unger, 2001), the specific aim of this study is to better understand the intersection of multiple identities experienced by bisexual individuals. Relying upon data collected by Herek, Glunt, and colleagues during their Northern California Health Study, in this exploratory study we examine the intersection of bisexual, religious/spiritual, and political identities by conducting an archival secondary analysis of 120 self-identified bisexual individuals. Among the significant findings, results suggest that higher LGB self-esteem scores and openness about sexual orientation correlated with higher levels of spirituality. Further, attraction to same sex partners was associated with perceiving sexual orientation as a choice, identifying as bisexual at a younger age, more likely to disclose one's sexual orientation, less likely to view religion as being socially important, and a higher score on the belief statement. We discuss the implications of these results and make suggestions for future research on the role of religion and spirituality in bisexual lives.

SO(32) heterotic line bundle models

NASA Astrophysics Data System (ADS)

Otsuka, Hajime

2018-05-01

We search for the three-generation standard-like and/or Pati-Salam models from the SO(32) heterotic string theory on smooth, quotient complete intersection Calabi-Yau threefolds with multiple line bundles, each with structure group U(1). These models are S- and T-dual to intersecting D-brane models in type IIA string theory. We find that the stable line bundles and Wilson lines lead to the standard model gauge group with an extra U(1) B-L via a Pati-Salam-like symmetry and the obtained spectrum consists of three chiral generations of quarks and leptons, and vector-like particles. Green-Schwarz anomalous U(1) symmetries control not only the Yukawa couplings of the quarks and leptons but also the higher-dimensional operators causing the proton decay.

How to Best Name a Place? Facilitation and Inhibition of Route Learning Due to Descriptive and Arbitrary Location Labels.

PubMed

Meilinger, Tobias; Schulte-Pelkum, Jörg; Frankenstein, Julia; Hardiess, Gregor; Laharnar, Naima; Mallot, Hanspeter A; Bülthoff, Heinrich H

2016-01-01

Establishing verbal memory traces for non-verbal stimuli was reported to facilitate or inhibit memory for the non-verbal stimuli. We show that these effects are also observed in a domain not indicated before-wayfinding. Fifty-three participants followed a guided route in a virtual environment. They were asked to remember half of the intersections by relying on the visual impression only. At the other 50% of the intersections, participants additionally heard a place name, which they were asked to memorize. For testing, participants were teleported to the intersections and were asked to indicate the subsequent direction of the learned route. In Experiment 1, intersections' names were arbitrary (i.e., not related to the visual impression). Here, participants performed more accurately at unnamed intersections. In Experiment 2, intersections' names were descriptive and participants' route memory was more accurate at named intersections. Results have implications for naming places in a city and for wayfinding aids.

How to Best Name a Place? Facilitation and Inhibition of Route Learning Due to Descriptive and Arbitrary Location Labels

PubMed Central

Meilinger, Tobias; Schulte-Pelkum, Jörg; Frankenstein, Julia; Hardiess, Gregor; Laharnar, Naima; Mallot, Hanspeter A.; Bülthoff, Heinrich H.

2016-01-01

Establishing verbal memory traces for non-verbal stimuli was reported to facilitate or inhibit memory for the non-verbal stimuli. We show that these effects are also observed in a domain not indicated before—wayfinding. Fifty-three participants followed a guided route in a virtual environment. They were asked to remember half of the intersections by relying on the visual impression only. At the other 50% of the intersections, participants additionally heard a place name, which they were asked to memorize. For testing, participants were teleported to the intersections and were asked to indicate the subsequent direction of the learned route. In Experiment 1, intersections' names were arbitrary (i.e., not related to the visual impression). Here, participants performed more accurately at unnamed intersections. In Experiment 2, intersections' names were descriptive and participants' route memory was more accurate at named intersections. Results have implications for naming places in a city and for wayfinding aids. PMID:26869975

9-1529 : low-cost safety solutions, pavement preservation, and maintenance practices for rural highways.

DOT National Transportation Integrated Search

2014-08-01

Task 1 : The objective of this project was to develop and : demonstrate innovative low-cost solutions to : improve safety at stop-controlled intersections. : Preliminary directives from the project panel : were to focus on treatments on the minor str...

Passive roadside reflectors and communications systems for improvement of radar reliability

DOT National Transportation Integrated Search

2006-06-01

The use of radar in automotive applications such as adaptive cruise control is limited to detecting : target vehicles directly in front of the host vehicle. Vehicles around a curve on a highway and : cross traffic vehicles at an intersection cannot b...

Searching LOGIN, the Local Government Information Network.

ERIC Educational Resources Information Center

Jack, Robert F.

1984-01-01

Describes a computer-based information retrieval and electronic messaging system produced by Control Data Corporation now being used by government agencies and other organizations. Background of Local Government Information Network (LOGIN), database structure, types of LOGIN units, searching LOGIN (intersect, display, and list commands), and how…

Authenticity in Leadership: Intersectionality of Identities.

PubMed

Jones, Susan R

2016-12-01

This chapter situates leadership and the process of becoming a leader within an understanding of identity, particularly intersecting social identities and intersectionality. © 2016 Wiley Periodicals, Inc., A Wiley Company.

The intersectionality framework and identity intersections in the Journal of Counseling Psychology and The Counseling Psychologist: A content analysis.

PubMed

Shin, Richard Q; Welch, Jamie C; Kaya, Aylin E; Yeung, Jeffrey G; Obana, Chynna; Sharma, Rajni; Vernay, Collin N; Yee, Stephanie

2017-10-01

The framework of intersectionality is a powerful analytical tool for making sense of how interlocking systems of privilege and oppression are experienced by individuals and groups. Despite the long history of the concept, intersectionality has only recently gained attention in psychology. We conducted a content analysis to assess counseling psychology's engagement with an intersectional perspective. All articles published in the Journal of Counseling Psychology (n = 4,800) and The Counseling Psychologist (n = 1,915) from their first issues until July 2016 were reviewed to identify conceptual and empirical work focused on intersectionality. A total of 40 articles were identified and examined for themes. Limitations and future directions are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Children's Perception of Gap Affordances: Bicycling Across Traffic-Filled Intersections in an Immersive Virtual Environment

ERIC Educational Resources Information Center

Plumert, Jodie M.; Kearney, Joseph K.; Cremer, James F.

2004-01-01

This study examined gap choices and crossing behavior in children and adults using an immersive, interactive bicycling simulator. Ten- and 12-year-olds and adults rode a bicycle mounted on a stationary trainer through a virtual environment consisting of a street with 6 intersections. Participants faced continuous cross traffic traveling at 25mph…

The Effects of General and Homophobic Victimization on Adolescents' Psychosocial and Educational Concerns: The Importance of Intersecting Identities and Parent Support

ERIC Educational Resources Information Center

Poteat, V. Paul; Mereish, Ethan H.; DiGiovanni, Craig D.; Koenig, Brian W.

2011-01-01

Many adolescents experience peer victimization, which often can be homophobic. Applying the minority stress model with attention to intersecting social identities, this study tested the effects of general and homophobic victimization on several educational outcomes through suicidality and school belonging among 15,923 adolescents in Grades 7…

Traffic & rural intersection monitoring with a solar-based infrared wireless system : phase 2 final report, long term effect and justification for further analysis, May 2008 [summary].

DOT National Transportation Integrated Search

2008-05-01

This study concerns the development and evaluation of a dynamic speed monitoring (DSM) system for use at rural intersections. The purpose of the DSM system is to give traffic speed feedback to drivers via an advisory sign, with the goals of improving...

Educational Software for Interactive Training of Students on the Theme "Mutual Intersecting of Pyramids and Prisms in Axonometry"

ERIC Educational Resources Information Center

Karaibryamov, Samet; Tsareva, Bistra; Zlatanov, Boyan

2012-01-01

This work acquaints with the program Sam for interactive computer training of students on the theme "Mutual intersecting of pyramids and prisms in axonometry". The program containing three modules--teacher, student and autopilot--allows for briefest time to teach and study the whole variety of the tasks on this theme. A classification of…