Theses supervised by Mustafa (Co-Supervisor) İlkan
10 theses · Eastern Mediterranean University
Do eReferral, eWOM, Familiarity, and Cultural Distance Predict Enrollment Intention among Educational Tourists? Application of Artificial Intelligence Technique
The extant literature has demonstrated the benefits of electronic word-of-mouth (eWOM), electronic referral (eReferral), familiarity, and cultural distance on behavioral outcomes separately. Research efforts have overlooked their collective effects from educational tourism perspective. This dissertation fecundates the concept of eWOM, eReferral, familiarity, and cultural distance with social network theory to explore their influence on enrollment intention. Cross-sectional data garnered from educational tourists based on a judgmental sampling technique were subjected to linear modeling and artificial neural network modeling in training and testing phases. Empirical analysis based on a single-sourced data of n=931 educational tourists confirmed the influence of eReferral, eWOM, familiarity, and cultural distance on enrollment intentions symmetrically (linear modeling) and asymmetrically (artificial neural network). The artificial neural network technique exerted higher predictive relevance and validity. This dissertation provides meaningful theoretical, practical, and methodological insights into the collective and contributive effects of eReferral, eWOM, familiarity, and cultural distance on ed-tourist enrollment intentions. Practically, implications for university administrators and marketers are prescribed. Methodologically, the research provides incremental insights from orthodox (i.e., linear) and contemporary analytical (i.e., artificial neural network) techniques, which are relevant to the wider management and tourism literature. The results suggest that eReferral, eWOM, familiarity and cultural distance can predict intention to enroll in both symmetrically (linear modelling) and asymmetrically (Artificial Neural Network) manner. The asymmetric modeling possesses greater predictive validity and relevance. This study contributes theoretically and methodologically to the management literature by validating the proposed relationships and deploying contemporary method such as Artificial Neural Network.
Experimental Investigation of an Inclined Combined Solar Hot Water and Desalination System
The main aim of this research is to design a new solar collector for heating the water and use it in water desalination. This study gives information about the inclined solar water desalination and heating system design, construction and the results of the system. The performance of the inclined solar water desalination and heating system was studied with different mass flow rates and systems. Different systems and mass flow rates were compared. In this study 6 different mass flow rates and 2 different systems were tested. In the first system, two different storage tanks were used. In the first system one storage tank sends the water to the solar collector and then hot water goes to second storage tank. There is no circulation in this system. This system was tested with 3 different mass flow rates and the average efficiency of the system is 65% and average daily water production is 2134,1 ⁄. In the second system one storage tank was used. The second system has circulation and because of this the inlet temperature of the water increases. The same water circulates in this system and this reduces the water quality. This system was tested with 3 different mass flow rates. The average efficiency of the system is 72% and daily average water production is 2833.17 ⁄. The cost of the collection and payback analysis of the system are shown in the economic analysis section. Keywords: Solar energy, inclined water desalination and heater, efficiency, daily water production
Improving Route Stability of the AODV Routing Protocol Using Fuzzy Approach
There are many studies that focus on improving source–destination route stability and lifetime by modifying the existing wireless mobile Ad Hoc networks (MANETs) routing protocols. In this study, a fuzzy based approach is proposed to enhance the Ad Hoc on-demand distance vector (AODV) routing protocol’s performance by selecting the most trusted nodes to construct a route between the source and the final destination nodes. In this scheme, the nodes’ parameters, like residual energy, node mobility, and hop count are fed through a fuzzy logic inference system to compute the value of the node trust level, which can be used as a metric to construct an optimal path from source to destination. The simulation results show that the proposed Fuzzy AODV approach performs better than the classical AODV routing protocol. The average routing load and average end to end delay metrics were improved in all cases of different network parameter changes as node speed, number of nodes, and pause times for both of classical AODV and Fuzzy AODV routing protocols. Whereas the Packet Delivery Ratio (PDR) and average network throughput were slightly varied in different network parameter changes. As shown in simulation results, the effects of fuzzy logic inference modifications that have improved the route selection procedure of classical AODV. This route selection scheme reduces the rebroadcasting of overhead route control (RREQ) packets at each intermediate node which receives more than one copy of the same RREQ packets. This will reduce the number of overhead route control packets flooding throughout the network in route discovery stages of classical AODV routing protocol. As a result, it decreases the network congestion and helps the network to retain their limited network resources. Keywords: AODV, routing protocol, MANET, fuzzy logic, trusted nodes.
Experimental Investigation of Perforated Glazed Transpired Solar Air Heaters
In this experimental study, performances of a novel type solar air heater, perforated glazed solar air heater (PGSAH), and a black coloured unglazed transpired solar air heater (UTSAH) was surveyed. The current study involves two series of experiments. The first series of experiments are accomplished on single pass perforated glazed solar air heaters (SPGSAHs) with different inner colours which have no absorber plates inside the collectors. The second series of experiments have been carried out on double pass perforated glazed solar air heater with packed beds (DPGSAHPB) which are used as absorber plates. The thermal performances of SPGSAH having different inner collector colours, DPGSAH with packed beds and UTSAH were investigated experimentally in this study. Moreover, in order to compare the performances of the PGSAHs and UTSAH, two PGSAHs having perforated plexiglas glazing were constructed and a UTSAH with black coloured perforated sheet metal utilized as an absorber plate was constructed. The diameters of the holes of plexiglas covers and sheet metal cover were 3 mm and the pitch distance was 30 mm. The fans sucked ambient air into the collectors through the perforated plexi glass in the PGSAHs. The thermal efficiency and outlet temperature of collectors were obtained between various mass flow rates of 0.014 and 0.036 kg/s. It was inferred from results that highest value of thermal efficiency and temperature differences were obtained using green and black PGSAHs in first series of experiments and DPGSAH which utilizes iron wools as packing material in second series of experiments. The results indicated that the thermal efficiencies of UTSAHs were lower than the PGSAHs thermal efficiencies. The maximum values of thermal efficiencies for black, green, blue, red, violet, light yellow and white SPGSAHs are found 85%, 84%, 76%, 65%, 61%, 54% and 55% respectively, at same mass flow rate, the highest thermal efficiency for UTSAH was 50%. Moreover, the average thermal efficiency for DPGSAH with iron wools and DPGSAH with mesh layers are 81.9 %, 75% respectively for air mass flow rate 0.036 kg/s. The highest temperature differences (ΔT) observed were 17.9℃, 17.3℃, 15.4℃ for black, green and blue SPGSAHs respectively for air mass flow rate of 0.024 kg/s. Furthermore, the maximum ΔT for DPGSAH with iron wools is obtained around 29.1℃ at a minimum mass flow rate of 0.014 kg/s. Within specified range of air mass flow rates from 0.014 to 0.036 kg/s, the thermal efficiency of PGSAH enhanced when the air flow rate was increased. As expected, the results demonstrate that thermal efficiencies of PGSAHs were increased if packed bed materials were employed or the collectors were painted by dark colours. The thermal efficiency and outlet air temperature of the DPGSAHPB was greater than the SPGSAH for the same mass flow rates. The DPGSAHPB which utilizes iron wools as packing material had better thermal performance than the DPGSAHPB with mesh layers used as packing material. Keywords: Renewable energy, perforated glazed solar air heater, transpired solar air heater, double pass, thermal efficiency, collector colours
Motivational Factors for eLancing: Evidence From Turkey
This study aims to explore the motivational factors for Turkish internet freelancers (eLancers) to engage in internet freelancing (eLancing). eLancing is a new phenomenon which has started in the 21st century. It is a networked online platform used for distributive problem-solving, economic production and service delivery. eLancing includes websites where eLancers are interested in being employed, and employers looking for eLancers to perform some types of work on the web. Forty eight semi-structured interviews conducted online with Turkish eLancers on elance.com. As a result, ten (10) primary motivations for participation have emerged. They are namely: (1) Work-family balance, flexibility and autonomy, (2) Economic incentives, (3) Skills development, (4) Trust and transparency, (5) Geographical location, (6) Unemployment, equality and disability, (7) Higher returns, (8) Reputation, (9) Passion and enjoyment of problem-solving, and (10) Revenge. The current study has added rich qualitative data to the scanty eLancing literature. Implications for policy makers, limitations and future studies are discussed. Keywords: eLancers, eLancing, motivations, Turkey.
Experimental Investigation of the Effect of Absorber Plate Temperature on Double Slope Inclined Solar Water Desalination Still
Solar energy can be used for potable water production from brackish water. In this study the effect of the absorber plate temperature on the inclined solar water desalination having double sloped cover (DS-ISWD) performance was experimentally studied. The DS-ISWD system with net cavity area of 1.5 m2 was constructed and it has two slope glazing; each inclined 250 and four spray jet nozzles were installed at equal intervals within the DS-ISWD. The experience gained form the operation of spray jet solar desalination at the Eastern Mediterranean University, N. Cyprus has revealed the importance of feeding water volume on the system performance. The DS-ISWD system with four jet sprays was tested with different on set temperatures of 40, 45, 50, 55, 60o C in spring (April). The maximum daily yield achieved was 3.85 kg/day m2 when the absorber plate temperature was kept at 55oC. The fresh water yield at 40, 45, 50, 55, and 60oC absorber plate temperatures were 3.6, 3.71, 3.72, 3.85 and 3.68 kg/day m2 respectively. It was observed that when the onset temperature was set 65oC the pump was not in operation after 14:00 hrs. This indicates that the absorber plate temperature was less than 65oC so the system stops generating fresh water after 14:00 hrs. Therefore, the 65 oC plate temperature was ignored in spring tests. The daily average efficiency of DS-ISWD system was observed to be 33.8% for 55oC set-point temperature. The effect of continuous water spraying on the DS-ISWD productivity was also examined. When the absorber plate was at 40oC the pump operated continuously i.e., the feedwater was continuous. The experiments were also conducted in July and the optimum absorber temperature was found to be 65oC with 4.2 kg/day m2 of fresh water production. At 60oC the pump operated continuously and the fresh water production was 5% less than the optimum whereas, the production was decreased by 5% when the absorber plate was at 70oC. From the obtained results it can be concluded that the performance of the DS-ISWD depends on the absorber plate temperature. The DS-ISWD performance also depends on the solar insolation, feedwater temperature, sprayed water size and other climatic parameters. Keywords: Potable water, inclined solar water desalination, absorber plate temperature, thermal efficiency
360-Degree Video Marketing: The Role of Emerging Technologies in Tourism Destination Choice
The use of 360-degree videos in marketing plans allows destination marketers to give a virtual adventure to their customers before their actual trip. Combining the motivation theory and Technology Acceptance Model (TAM), a research approach was developed to examine whether 360-degree videos are influential in creating a more positive attitude and influencing users' behavioral intentions towards a destination. To evaluate the relationships between the proposed constructs, structural equation modeling (SEM) was used. An online survey collected data from European participants (n = 598) regarding Hong Kong as a tourism destination. The results revealed that both intrinsic and extrinsic motivators influence tourists’ satisfaction with a 360-degree experience of the destination that indirectly affects their visit and electronic word of mouth (eWOM) intentions through behavioral involvement. Overall, the findings indicate that a 360-degree video effectively attracts customers and influences their attitudes and behaviors. The research includes theoretical, managerial implications, and guidelines for future studies relying on these results.
Nepotism and Tolerance to Workplace Incivility in the Hospitality Sector: Moderating Role of Authentic Leadership
[Abstract Not Available]
An Experimental Investigation of a Concentrating PVT Systems
Solar Photovoltaic (PV) systems harness the solar energy from the sun and converts it into electrical energy. The electrical efficiency of a PV system depends on the type of cells, and the working temperature of the system. The efficiency of a PV module decreases as its temperature increases due to incoming solar radiation. Even with the decreasing cost of the PV modules, the efficiency is still low due to the above mentioned factors (ideal conversion efficiency is about 15%) and most of the radiation reaching to the PV modules is wasted as heat. Therefore, there is a need to remove or better still utilize this waste energy. The Photovoltaic- thermal system (PV/T) is a hybrid system that produces thermal energy as well as electrical energy. This thesis experimentally investigates the use of solar concentrated photovoltaic-thermal system (CPV/T) to boost the overall productivity of the solar PV module. In CPV systems mirrors or lenses are used to concentrate sunlight onto solar cells. High-efficiency solar cells are used in CPV systems where concentration ratios are high but conventional solar cells can be used at low concentration ratios (i.e., less than 10). The studied CPV/T system uses mirrors to intensify the solar radiation on the PV module of about 3 times. The performance of the CPV/T collector was analyzed and compared to that of the reference PV module working under the same weather conditions of the Northern Cyprus in the month of June. The CPV/T system was established by attaching a set of 4 mirrors to the module frame and a glass duct mounted on the top of the module for cooling purpose. With Water used as the coolant and heat carrier. The inlet temperature of the coolant was varied between 14 oC and the ambient temperature (i.e., 14°C, 18°C, 22°C and ambient temperature). In this experimental work, it was found that the CPV/T collector performed better using an inlet cooling water temperature of 14°C. The maximum electrical power output from the CPV/T system was 49.06 W yielding a 3.3 times the rated power of the PV ( 15 W at STC), and its maximum thermal output was 920 Wh/m2. Keywords: Photovoltaic, CPV/T collector, Electrical power, Thermal energy.
Concentrated Photovoltaic (PV) Cogeneration Systems
Solar photovoltaic (PV) technology systems utilize solar energy to generate electricity. The increment in PV cell's operating temperature causes a significant reduction in the electrical efficiency. In this thesis, a water cooling system was combined with a PV module to construct a type of collectors known as hybrid photovoltaic/thermal (PV/T) collector. PV/T collector operates as a cogeneration system by converting solar energy into electrical energy and thermal energy simultaneously. A concentrating photovoltaic/thermal (CPV/T) collector was then formed by concentrating sunlight onto the collector surface using a set of ordinary flat mirrors to generate more electricity and thermal output at minimal costs. Performance of the CPV/T collector was investigated experimentally and compared with a PV module used as reference. The reference PV module was an ordinary i.e. it was neither concentrated nor cooled. The experimental investigation was conducted in January under climatic conditions of Northern Cyprus. By using two mirrors, the CPV/T collector produced a maximum electrical power output of 32.55 W which is 2.17 times the 15 W rated power of the PV module under standard test conditions (STC) and maximum thermal energy output of 126.23 Wh. When three mirrors were used, the maximum electrical power output was found to be 49.74 W which is 3.3 times the PV rated power and maximum thermal energy output of 189.35 Wh. Keywords: Photovoltaic, CPV/T collector, Electrical power, Thermal energy.