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The performance of resultant topological structure of Kohonen Self Organizing Map SOM is highly dependent of the learning rate and neighborhood parameters. In literature there are plenty many different types of approaches to and proposals for those parameters. It has been investigated that in general the learning rate and neighborhood parameters are data independent and predefined before the training period. Here in this paper a novel approach has been proposed to change the learning rate parameter according to the interaction of neurons with data. During training, the worst matching neuron also tracked and used to trace the formation of topological structure of SOM. A slight modification on conventional learning rate with proposed method has a considerable influence on resultant topologies in a positive way. The effects of this approach have been tested with the real world problem and different synthetic data.

The role of air transport in transportation system is increasing every year. However, there can be difficulties to meet this increase. Therefore, efforts to resolve the problems in air transport become important. Delays and congestions are seen in the air transport system are among these problems. Airports are one of the most critical points of air transportation system facing these problems. One of the measures to be taken to resolve this problem is improving the existing system. Istanbul Ataturk Airport, the busiest airport in Turkey, often experiences delay and congestion problems. To propose a solution to these problems and to reduce runway occupancy time in Istanbul Ataturk Airport, additional fast-exit taxiways to the runway 05 were constructed. In this study, the impact of infrastructure changes made in Istanbul Ataturk Airport is examined, and traffic flow and capacity analysis is carried out comparing three different runway configurations. In consequence of the construction of additional fast-exit taxiways to the runway 05, airport capacity has increased 1.9 per cent. It is also shown that the high average delay time reduces airport capacity.

The scope of this study is to determine the effectiveness of using rivets in the adhesive joints in order to combine plastic-based composite materials which are often used in today's engineering structures, to the joint strength. For this purpose, double lap joints are prepared in 3 different types of configuration included adhesive, pinned and both adhesive and pinned and also prepared in 3 different overlap lengths as 30, 45 and 60 mm. Stress-strain diagrams were derived by exposing the joints obtained, to the axial tensile test and then the most appropriate joint type was determined by comparing each of the results obtained. The evaluation of the results pointed out that the hybrid joints where adhesive and rivet are used together can carry much more load than the joints where the only adhesive was used or the joints which are combined with a rivet in terms of joint strength.