Security at major locations of economic or political importance is a key concern around the world, particularly given the threat of terrorism. Limited security resources prevent full security coverage at all times, which allows adversaries to observe and exploit patterns in selective patrolling or monitoring, e.g. they can plan an attack avoiding existing patrols. Hence, randomized patrolling o...

Aviation industry is highly dynamic and demanding in nature that time and safety are the two most important factors while one of the major sources of delay is aircraft on ground because of it complexity, a lot of machinery like vehicles are involved and lots of communication are involved. As one of the aircraft ground services providers in Hong Kong International Airport, China Aircraft Service...

In 1986, the total profits of the U.S. airline industry were of the order of $800 million, while its total delay costs due to congestion approached the figure of $2 billion. Motivated by this important problem of congestion costs and observing that ground delays are far more preferable than airborne delays, we have formulated and studied generic integer programming models in order to assign opt...

The problem of assigning gates to arriving and departing flights is one of the most important problems in airport operations. We take into account the real multi-criteria nature of the problem by optimizing a total of nine gate allocation objectives that are oriented both on convenience for airport/airline services and passenger comfort. As far as we are aware, this is the largest number of obj...

Large cities with multi-modal traffic systems are complex that need to be understood to help analyze and make policy decisions. Understanding such complex systems requires simulation, experimentation and observation. We have built a MUST system to simulate big cities with multi-modal traffic system with large number of agents (humans), each participating in many movement activities. Building su...

Forecasts of departure demand are one of the driving inputs to tactical decision-support tools (DSTs) for airport surface traffic. While there are well-known results on averageor worst-case forecast uncertainty, it is the forecast errors which occur under best-case minimum-uncertainty conditions which constrain robust DST design and the achievable traffic benefits. These best-case errors have n...

Limousine Services Ltd. (Airport Limousine), a subsidiary of Swire Travel, one of the largest and oldest travel management companies in Hong Kong and widely recognized as the leader in service quality in the local travel industry. Swire Travel has more than 50 years of history and is part of the 145-year old worldwide Swire group. The main business of Airport Limousine is a 24-hour luxury limou...

Multi-server queuing analysis can be used to estimate average wait times and queue lengths at toll and parking exit plazas given arrival rates, number of servers, and service rates. These queuing models approximate the performance of queuing systems with multiple queues. While the queuing equations are useful where there are multiple servers, they do not fully reflect the operation of a toll pl...

This article presents a control approach that enables an autonomous operation of fleets of unmanned snow ploughs at large airports. The proposed method is suited for the special demands of tasks of the airport snow shovelling. The robots have to keep a compact formation of variable shapes during moving into the locations of their deployment and for the autonomous sweeping of runways surfaces. T...