published_or_final_version / Civil Engineering / Doctoral / Doctor of Philosophy

published_or_final_version / abstract / Computer Science / Master / Master of Philosophy

published_or_final_version / Physics / Master / Master of Philosophy

No description available.

No description available.

published_or_final_version / abstract / Civil Engineering / Master / Master of Philosophy

published_or_final_version / Civil Engineering / Master / Master of Philosophy

This dissertation reported on the findings of the characteristics of the pedestrian flows in Chinese New Year Eve Fair in Hong Kong and, the recommendations to its crowd control measures. Since most of the pedestrian flow models were developed for general purposes under normal condition, special models developed specifically for major events such as bazaars, fairs and festivals in Hong Kong were required to understand their pedestrian flow patterns. In this dissertation, pedestrian flows in the Fair were videotaped and data was extracted for calibrating several pedestrian flow models. These included the conventional models developed by Greenshields, Greenberg, Pipes-Munjal, Underwood, Drake, Wong et al. and four modifications of these models for simulating isotropic and bi-directional pedestrian flow scenarios. The free flow speed of the pedestrians in the Chinese New Year Eve Fair was found to be around 0.69-0.84 m/s, slower than those identified in other researches. Besides, the results of these models showed the relationships between walking speed, density and flow of the pedestrians in the Fair. Also, the effects of bi-directional flow to pedestrian flows were assessed and quantified. These findings obtained from models were then used as a basis for formulating crowd control strategy of major events in Hong Kong. / published_or_final_version / Transport Policy and Planning / Master / Master of Arts in Transport Policy and Planning

Walking is an environmentally friendly mode of transportation. A better understanding of pedestrian activities and effective planning of walking facilities are particularly important for densely populated Asian cities like Hong Kong. Empirical studies on pedestrian flows can be classified as controlled experiments and observational surveys. Controlled experiments are flexible and can be designed to fulfill the requirements of specific studies and eliminate influence from unrelated factors. Observational surveys provide data for pedestrian movements in different types of walking facilities. This thesis aims to develop a mathematical model for multidirectional pedestrian flows based on knowledge obtained from both a controlled experiment and observational surveys on three different walking facilities. Bayesian inference is adopted for model calibration, as it can combine the prior information from the controlled experiment and the observed data from the observational surveys. The proposed model is based on Drake’s (1967) model of traffic flow. However, multidirectional pedestrian flows are much more complicated than the unidirectional and bidirectional flows. Therefore, instead of relating the speed of a pedestrian stream solely to pedestrian density, the flow ratio and intersecting angles between streams are introduced as factors that may influence stream speed. The proposed model takes the form of a set of structural equations rather than a single deterministic function. By applying Bayesian inference, the proposed model is calibrated with the three sets of observed data respectively, based on the prior distribution specified by the controlled experiment results. Finally, pedestrian movements in three different walking facilities are analyzed based on the properties of the calibrated model. / published_or_final_version / Civil Engineering / Master / Master of Philosophy

An intensive examination was conducted to test the credibility of current traffic signal change interval policies founded on a kinematic equation developed nearly 30 years ago. The investigation involved the review of relevant literature as well as an extensive collection of data. The literature review and data analysis revealed that current change interval policies rely on the disproven assumption that traffic decelerates at a constant rate. The data analysis also demonstrated that traffic approach speed and deceleration distance affect the manner in which deceleration occurs. Based on the data analysis, an alternative treatment of the kinematic equation is proposed using surrogate deceleration rates. The surrogate rates offer a pragmatic set of input for the kinematic equation. Therefore, rather than yielding a change interval based on an inaccurate assumption, agencies can implement change intervals which are responsive to local traffic.