Methodologies For The Analysis Of Checked Baggage Inspection Systems

To enhance the security of the aviation system it is necessary to have a Checked Baggage Inspection System (CBIS) that is effective (that is, the highest possible detection probability or minimum false clear probability) yet efficient (that is, minimize the false alarm probability that causes inconvenience to passengers). The first objective of this thesis is to review passenger, carry-on and checked baggage inspection procedures at airports The second objective of this thesis is to develop a methodology using the optimization approach to set the optimal values of the sensitivity of the screening devices to minimize the total cost of inspecting each baggage. The methodology is developed for the two-device screening system. The sensitivity threshold is given by the value of µ1 and µ2, for the primary and secondary screening machine, respectively. The output signal of each screening device is modeled by the Beta distribution. The outputs are compared to µ1 and µ2 Another important aspect which has to be considered for an efficient baggage screening system is the system capacity. A badly designed CBIS can cause delays in baggage screening which could in worst case lead to the delay of the aircraft departure or in need of using another flight to deliver the baggage to the requested destination. The third objective of this thesis is to calculate of the average waiting times, average queue length and number of devices needed for the baggage screening using the M/G/m queuing model. The probabilities obtained in the precedent work are used for the calculation of the number of baggage sent to the secondary screening. First the equations of the M/G/m queuing model are described. Then two different examples are created to help to illustrate the calculations. The queuing theory does not allow an analyst to consider higher arrival rate than the system can handle even for a short duration. The arrival rate at the airport varies according to the number of departing flights. The number of baggage that has to be screened sometimes exceeds the capacity of the system which can create a queue. This queue may not last long but can occasionally cause significant delay. This scenario can be analyzed by simulation. The fourth objective of this thesis is to evaluate how well the VISSIM microscopic traffic simulation software may be used to model CBISs. The arrangement of four screening devices in primary screening and two devices in secondary screening is modeled using the VISSIM software. The output data were compared with the results from queuing theory: the number of bags, the delay of bags, the queue length, and travel times