13 resultados para pedestrians
em Deakin Research Online - Australia
Resumo:
Modelling and prediction of pedestrian routing behaviours within known built environments has recently attracted the attention of researchers across multiple disciplines, owing to the growing demand on urban resources and requirements for efficient use of public facilities. This study presents an investigation into pedestrians' routing behaviours within an indoor environment under normal, non-panic situations. A network-based method using constrained Delaunay triangulation is adopted, and a utility-based model employing dynamic programming is developed. The main contribution of this study is the formulation of an appropriate utility function that allows an effective application of dynamic programming to predict a series of consecutive waypoints within a built environment. The aim is to generate accurate sequence waypoints for the pedestrian walking path using only structural definitions of the environment as defined in a standard CAD format. The simulation results are benchmarked against those from the A* algorithm, and the outcome positively indicates the usefulness of the proposed method in predicting pedestrians' route selection activities. © 2014 Elsevier Ltd. All rights reserved.
Resumo:
This paper describes the procedure for detection and tracking of a vehicle from an on-road image sequence taken by a monocular video capturing device in real time. The main objective of such a visual tracking system is to closely follow objects in each frame of a video stream, such that the object position as well as other geometric information are always known. In the tracking system described, the video capturing device is also moving. It is a challenge to detect and track a moving vehicle under a constantly changing environment coupled to real time video processing. The system suggested is robust to implement under different illuminating conditions by using the monocular video capturing device. The vehicle tracking algorithm is one of the most important modules in an autonomous vehicle system, not only it should be very accurate but also must have the safety of other vehicles, pedestrians, and the moving vehicle itself. In order to achieve this an algorithm of multi resolution technique based on Haar basis functions were used for the wavelet transform, where a combination of classification was carried out with the multilayer feed forward neural network. The classification is done in a reduced dimensional space, where principle component analysis (PCA) dimensional reduction technique has been applied to make the classification process much more efficient. The results show the effectiveness of the proposed methodology.
Resumo:
The city and the urban environment became extremely important in the daily lives of the increasing number of urban populations across the world. Urban research acknowledges that planning urban places should be responsive to the diversity of population. The aim of this paper is to analyse the results of thermal comfort study in the outdoor urban places. The location has been monitored regarding standard comfort variables: air temperature, humidity, wind speed, and globe temperature. The quantitative assessment of comfort conditions was combined with a questionnaire of pedestrians’ thermal comfort perception. In this paper, the analysis of observed thermal sensation with regard to gender and cultural background concerning the sensitivity of different groups to heat and cold is presented.
Resumo:
We present a comparative evaluation of the state-of-art algorithms for detecting pedestrians in low frame rate and low resolution footage acquired by mobile sensors. Four approaches are compared: a) The Histogram of Oriented Gradient (HoG) approach [1]; b) A new histogram feature that is formed by the weighted sum of both the gradient magnitude and the filter responses from a set of elongated Gaussian filters [2] corresponding to the quantised orientation, called Histogram of Oriented Gradient Banks (HoGB) approach; c) The codebook based HoG feature with branch-and-bound (efficient subwindow search) algorithm [3] and; d) The codebook based HoGB approach. Results show that the HoG based detector achieves the highest performance in terms of the true positive detection, the HoGB approach has the lowest false positives whilst maintaining a comparable true positive rate to the HoG, and the codebook approaches allow computationally efficient detection.
Resumo:
In this paper, we present a system for pedestrian detection involving scenes captured by mobile bus surveillance cameras in busy city streets. Our approach integrates scene localization, foreground and background separation, and pedestrian detection modules into a unified detection framework. The scene localization module performs a two stage clustering of the video data. In the first stage, SIFT Homography is applied to cluster frames in terms of their structural similarities and second stage further clusters these aligned frames in terms of lighting. This produces clusters of images which are differential in viewpoint and lighting. A kernel density estimation (KDE) method for colour and gradient foreground-background separation are then used to construct background model for each image cluster which is subsequently used to detect all foreground pixels. Finally, using a hierarchical template matching approach, pedestrians can be identified. We have tested our system on a set of real bus video datasets and the experimental results verify that our system works well in practice.
Resumo:
Previous research has suggested that angry drivers may respond differently to potential hazards. This study replicates and extends these findings. Under simulated driving conditions, two groups of drivers experienced conditions that would either increase angry mood (N=12; men =6) or not (control group, N =12; men=6). All drivers then performed a neutral drive, during which they encountered a number of traffic events not experienced in the initial drive. These included vehicles emerging from driveways into their path and jaywalking pedestrians. Subjective anger, eye-movement behaviour and driving behaviours (speed and reaction times) were measured as drivers drove. Subjective moods (Profile of Mood States) were assessed before and after each drive. Anger-provoked drivers reported reliably higher increases in angry mood when compared with the control group after the initial drive, and these increases remained stable across the subsequent neutral drive. During the neutral drive, anger provoked drivers demonstrated evidence of more heuristic style processing of potential hazards, with shorter initial gazes at less apparent hazards and longer latencies to look back at jaywalking pedestrians obscured by parked vehicles. Anger-provoked drivers also took longer to make corrective actions to avoid potential collisions. It is concluded that anger-provoked drivers may initially make more superficial assessments of certain driving situations and consequently underestimate the inherent risk.
Resumo:
Prediction of pedestrians’ steering behaviours within the built environments under normal and non-panic situations is useful for a wide range of applications, which include social science, psychology, architecture, and computer graphics. The main focus is on prediction of the pedestrian walking paths and the influences from the surrounding environment from the engineering point of view.
Resumo:
A study on the pedestrian's steering behaviour through a built environment in normal circumstances is presented in this paper. The study focuses on the relationship between the environment and the pedestrian's walking trajectory. Owing to the ambiguity and vagueness of the relationship between the pedestrians and the surrounding environment, a genetic fuzzy system is proposed for modelling and simulation of the pedestrian's walking trajectory confronting the environmental stimuli. We apply the genetic algorithm to search for the optimum membership function parameters of the fuzzy model. The proposed system receives the pedestrian's perceived stimuli from the environment as the inputs, and provides the angular change of direction in each step as the output. The environmental stimuli are quantified using the Helbing social force model. Attractive and repulsive forces within the environment represent various environmental stimuli that influence the pedestrian's walking trajectory at each point of the space. To evaluate the effectiveness of the proposed model, three experiments are conducted. The first experimental results are validated against real walking trajectories of participants within a corridor. The second and third experimental results are validated against simulated walking trajectories collected from the AnyLogic® software. Analysis and statistical measurement of the results indicate that the genetic fuzzy system with optimised membership functions produces more accurate and stable prediction of heterogeneous pedestrians' walking trajectories than those from the original fuzzy model. © 2014 Elsevier B.V. All rights reserved.
Resumo:
Introduction The number of drivers with dementia is expected to increase exponentially over the coming decades. Most individuals with moderate-to-severe dementia (table 1) are unfit to drive.1 Drivers with moderate-to-severe dementia have higher rates of MVCs than age-matched controls.2 Identifying and preventing these individuals from driving is crucial, particularly in urban areas. The density of cars and pedestrians, and the complexity of traffic typically place greater demands on drivers in urban areas, and, therefore, require greater reactivity and forward planning than in rural environments.3 ,4 The ability to drive is a critical means of maintaining one's social inclusion, and is commonly a practical necessity. Therefore, decisions about the entitlement to drive should not unfairly restrict mobility or unnecessarily compound the disadvantages experienced by older people with mild cognitive impairment and early dementia (table 1), particularly as diagnoses are now being made earlier.1 This paper describes the difficulties inherent in addressing the question of when and in what circumstances a diagnosis of dementia might render a person unfit to drive and focuses on those who live in rural areas. We examine the consequences of dementia diagnosis on driving, driver testing requirements and licensing procedures, and the impacts of driving cessation. We then discuss how living in rural areas may alter the level of risk of drivers with dementia and practical implications for licensing policies.
Resumo:
Pedestrians movements have a major impact on the dynamics of cities and provide valuable guidance to city planners. In this paper we model the normal behaviours of pedestrian flows and detect anomalous events from pedestrian counting data of the City of Melbourne. Since the data spans an extended period, and pedestrian activities can change intermittently (e.g., activities in winter vs. summer), we applied an Ensemble Switching Model, which is a dynamic anomaly detection technique that can accommodate systems that switch between different states. The results are compared with those produced by a static clustering model (Hy-CARCE) and also cross-validated with known events. We found that the results from the Ensemble Switching Model are valid and more accurate than HyCARCE.
Resumo:
An important challenge for brick-and-mortar retail businesses is how to monitor the interest of customers in displays and products in a store. We investigate the effectiveness of the Microsoft Kinect as a sensor to monitor the behaviour of pedestrians, which may reflect their interest in a store display or advertisement. In a controlled environment, participants acting as pedestrians are requested to show different levels of interest as they pass an object that is being monitored by a Kinect sensor. The sensor collected measurements such as the positions and orientation of the pedestrian's body and head, which were analysed to detect the movements of the pedestrians and thus infer the behaviour they exhibited. Our results demonstrate that when the Kinect is able to detect a behaviour that indicates a pedestrian's interest in an object, then the classification of the level of interest in terms of the type of behaviour is reasonably accurate under varying light conditions and numbers of pedestrians.
Resumo:
This paper proposes a novel application of Visual Assessment of Tendency (VAT)-based hierarchical clustering algorithms (VAT, iVAT, and clusiVAT) for trajectory analysis. We introduce a new clustering based anomaly detection framework named iVAT+ and clusiVAT+ and use it for trajectory anomaly detection. This approach is based on partitioning the VAT-generated Minimum Spanning Tree based on an efficient thresholding scheme. The trajectories are classified as normal or anomalous based on the number of paths in the clusters. On synthetic datasets with fixed and variable numbers of clusters and anomalies, we achieve 98 % classification accuracy. Our two-stage clusiVAT method is applied to 26,039 trajectories of vehicles and pedestrians from a parking lot scene from the real life MIT trajectories dataset. The first stage clusters the trajectories ignoring directionality. The second stage divides the clusters obtained from the first stage by considering trajectory direction. We show that our novel two-stage clusiVAT approach can produce natural and informative trajectory clusters on this real life dataset while finding representative anomalies.
Resumo:
Martin Rumsby’s Eye I Aye (2007) appears a straightforward, almost naive film. A camera is zoomed into a flat image of a community bench in front of a shop, with cars and some pedestrians passing by. It could be any suburban street. At times the de-facto main characters Dida and Erana or their surrogates are seated there, both are of mixed race from Māori and Pākehā parents and the soundtrack frames their ‘history’. This meditation is interrupted by the weather, with sheets of raindrops caught by the camera’s autofocus, patterning the window, wiping out the outside scene. Later Rumsby also inserts his body and face between the camera and window, his eyes in shot re-securing the camera’s position. This technical tampering registers as unsettling and suspicious.