The invention of automobile brings some demerits. Among them, the most perilous and aching is traffic accidents. The extremely high costs associated with traffic accidents cause safety improvements to be an important objective of transportation engineering. However, the problem of traffic accident in Japan is still serious and far from the satisfactory level because total accident cost is still high because of the total number of traffic accident is about 98 times and injuries are 121 times higher (in 1999) than fatal accidents although the fatal accidents decreasing in recent years.

About 58.4% accident of total and 45.2% fatality at intersection elevate the importance of intersection accident where most frequent accident type is right-turn (AG1) accounting 25% to total followed by rear-end types (24%). Right -angle accident suffers the worst records having 33% fatality and 45% of left-turn accident was involved with motorcycle accident. These two striking features invigorate to enliven the microscopic model for these types of accident.

Opting the arm-base approach, this study lucratively developed logic for two new types of uninvestigated right-angle and left-turn angle accident. For right-angle accident vehicle invading the red or yellow signal l was identified as an ‘obstacle vehicle ’ and vehicle following the traffic signal properly coming from cross-street approach was identified as ‘following vehicle’. For left-turn accident, the first vehicle arriving at the left -turn lane intend to turn left is referred as ‘obstacle vehicle’ and the vehicle tried to flee away from the congested trunk road arriving in left lane which it already misses is referred as ‘following vehicle’. Based on the relationship between the disturbance, obstacle vehicle maneuvering and following vehicle reactions this study developed models for both of the accident and modifies right -turn model to enumerate the liaison between accident frequency and some explanatory variables which covered both flow and design characteristics of the intersection using Negative Binomial to counter the overdispersion issue usually discerned in accident data through maximum likelihood estimation of the parameters. The upshots of the models exhibits the influence of certain variables on angle accident which fruitfully explain the mechanism accident and assists to take certain meticulous countermeasures against that type of accident at intersection.

Implementation of GIS using existing risk model reveals some important characteristics about angle accident such as high-risk accident intersection lied along the ring road or national highways. Investigation of transferability reveals that outside of Tokyo metropolitan area the accident model accuracy was not good enough compared to that of in inside. The common trends and existence of blackspots and understanding the cause of accidents at black spots are also investigated. Most of the black spots are situated along the ring roads and more than 50% of intersection’s accident was accurately estimated by the model, which indicates that the developed model could be easily applicable for black spots too. Exploration of possible reasons and countermeasure reveals that blackspots tended to have poor visibility and inadequate sight distance. Finally, application of GIS using existing accident risk models allows the management to handle the high-risk as well as normal intersection successfully to lessen the accident frequency and continuously monitoring of this urban malaise.

During the last two decades, air transport world has witnessed dramatic changes. Air travel demand is expected to increase further with the introduction of large and faster aircraft. Continued traffic growth creates a need for effective longer range advance planning and requires a coordinated approach for design, development and operation of future of air transport network. Air transportation plays a very important role in the development of a country. Its importance in Bangladesh has increased with the privatization of domestic air transportation market. For the planning and management of air transport operators and improvement of the facilities and services, it is needed to understand the demand and cost structure under present and future conditions.

The special characteristics of air mode impose limitations on the application of various theories. Rapid changes in aviation system are continuously analyzed in abroad. The objective of this is to develop and analyze the domestic air transportation in Bangladesh.

This study addresses the present condition of air transportation in Bangladesh by analyzing the operation and level of service of the system, demand and supply structure and its related parameters of domestic air transport in Bangladesh. For the planning of infrastructure development and service improvement, several demand and cost models have been developed as well as their application to understand the effects of demand and supply side input variables on the performance indicators such as change in socio-economic, technological and transportation system with the air travel demand, change in profit and reduction of supply costs. The demand models have been calibrated using cross-sectional as well as time series data of the variables and it can predict the air travel demand quite satisfactorily. Successful application of the effect of Jamuna Bridge in air travel demand proves the validity of the models. Calculation of Biman’s loss of revenue demonstrates the successful application of the cost function. The study also highlights the difference of management efficiency between private sector and government sector (Biman) airline companies operating in the country. An equilibrium analysis converges dynamically towards the equality of factor affecting the quantity demanded and the factors that determine the quantity supplied. Calculation of consumer’s surplus reveals the users benefit.

International air transport is one of the most dynamic and fast-changing industries in the world. In order to compete with the international system, effectiveness of new ‘Hub-and-Spoke’ aviation system is also developed in the study.

The findings of this study can be used to improve the air transport system with an effective use of limited facilities, to aid the management of various airlines in developing the guidelines for operating in domestic routes and to help the planning and design of future infrastructure development of air transportation system in Bangladesh.