Yaşar University

About: Yaşar University is a education organization based out in Izmir, Turkey. It is known for research contribution in the topics: Exergy & Job shop scheduling. The organization has 760 authors who have published 1436 publications receiving 20813 citations. The organization is also known as: Yaşar Üniversitesi.

Ministers’ statements: a policy implementation instrument for sustainable tourism?

Abstract: Consistent communication of tourism policies by tourism ministers might raise public and industry awareness and promote support for sustainable tourism. The statements made by ministers contain messages that can inform the public and industry stakeholders, and potentially, these statements can draw attention to sensitive issues and bring about changes in practices that encourage sustainability in the tourism industry. Analyzing the statements of the five most recent tourism ministers in Turkey, delivered between 2001 and 2009, this study identifies the ministers’ priorities for tourism and compares them with the tourism policy objectives set out in Turkey's Tourism Strategic Action Plan. Further comparison is undertaken to see whether priorities changed within and between governments. The results of the content analysis indicate that the statements of the Turkish tourism ministers were economically driven and growth-oriented, and that there were inconsistencies between the ministers’ priorities and the co...

An iterated greedy algorithm for the hybrid flowshop problem with makespan criterion

Abstract: The main contribution of this paper is to present some novel constructive heuristics for the the hybrid flowshop scheduling (HFS) problem with the objective of minimizing the makespan for the first time in the literature. We developed the constructive heuristics based the profile fitting heuristic by exploiting the waiting time feature of the HFS problem. In addition, we also developed an IG algorithm with a simple insertion based local search for the first time in the literature, too. The benchmark suite developed for the HFS problem are used to test the performance of the constructive heuristics and the IG algorithm. The computational results show that constructive heuristics developed were able to further improve the traditional NEH heuristics for the HFS problem with makespan criterion. Furthermore, with a very short CPU times of 50nm miliseconds, the performance of the IG algorithm was very competitive to the PSO and AIS algorithms that were run for 1600 seconds.

Multi-Channel Joint Forecasting-Scheduling for the Internet of Things

Abstract: We develop a methodology for Multi-Channel Joint Forecasting-Scheduling (MC-JFS) targeted at solving the Medium Access Control (MAC) layer Massive Access Problem of Machine-to-Machine (M2M) communication in the presence of multiple channels, as found in Orthogonal Frequency Division Multiple Access (OFDMA) systems. In contrast with the existing schemes that merely react to current traffic demand, Joint Forecasting-Scheduling (JFS) forecasts the traffic generation pattern of each Internet of Things (IoT) device in the coverage area of an IoT Gateway and schedules the uplink transmissions of the IoT devices over multiple channels in advance, thus obviating contention, collision and handshaking, which are found in reactive protocols. In this paper, we present the general form of a deterministic scheduling optimization program for MC-JFS that maximizes the total number of bits that are delivered over multiple channels by the delay deadlines of the IoT applications. In order to enable real-time operation of the MC-JFS system, first, we design a heuristic, called Multi-Channel Look Ahead Priority based on Average Load (MC-LAPAL), that solves the general form of the scheduling problem. Second, for the special case of identical channels, we develop a reduction technique by virtue of which an optimal solution of the scheduling problem is computed in real time. We compare the network performance of our MC-JFS scheme against Multi-Channel Reservation-based Access Barring (MC-RAB) and Multi-Channel Enhanced Reservation-based Access Barring (MC-ERAB), both of which serve as benchmark reactive protocols. Our results show that MC-JFS outperforms both MC-RAB and MC-ERAB with respect to uplink cross-layer throughput and transmit energy consumption, and that MC-LAPAL provides high performance as an MC-JFS heuristic. Furthermore, we show that the computation time of MC-LAPAL scales approximately linearly with the number of IoT devices. This work serves as a foundation for building scalable JFS schemes at IoT Gateways in the near future.