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The optimum insulation thickness of the external wall for four various cities from four climate zones of Turkey, energy savings over a lifetime of 10 years and payback periods are calculated for the five different energy types and four different insulation materials. Foamboard 3500, Foamboard 1500, extruded polystyrene and fiberglass as insulation material are selected. In this study, it is calculated the value of the amount of the net energy savings using the P1–P2 method. The results show that optimum insulation thicknesses vary between 1.06 and 7.64 cm, energy savings vary between 19 $/m2 and 47 $/m2, and payback periods vary between 1.8 and 3.7 years depending on the city and the type of fuel. The highest value of energy savings is reached in A?r? for LPG fuel type, while the lowest value is obtained in Ayd?n for natural gas.  相似文献   
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In this study, an exergoeconomic model was developed for analysis and optimization of solar heating systems with residential buildings. The optimum collector area (AcAc) and storage volume (VV) for solar-assisted heating system in the Elaz??, Turkey (38.7°N)(38.7°N), weather conditions were obtained using MATLAB optimization toolbox. The energy and exergy losses in each of the components of a solar heating system with seasonal storage were also determined. The results showed that the exergy loss and total cost increased with increasing per house collector area for the trapeze and cylindirical tanks. It was found that the total cost of the cylindrical tank system was higher than that of the other trapeze tank system. The exergy loss at the cylindrical tank was 19.8%, while the exergy loss at the trapeze tank was 8.3%.  相似文献   
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The optimum insulation thickness of the external wall for four cities from four climate zones of Turkey, energy savings over a lifetime of 10 years and payback periods are calculated for the five different energy types and four different insulation materials applied externally on walls. Extruded polystyrene, expanded polystyrene, nil siding and rock wool as wall insulation material are selected. In this study, the net energy cost savings are calculated using the P1P2 method. The results show that energy cost savings vary between 4.2 $/m2 and 9.5 $/m2 depending on the city and insulation materials. The highest payback period value with 2.25 years in Mersin found by using natural gas as an energy source for heating, while the lowest value is reached by using LPG as an energy source in Bitlis.  相似文献   
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This exploratory experimental study investigates the impact of motivational strategies based on the Attention, Relevance, Confidence, Satisfaction, and Volition (ARCS-V) model on online learners' academic performance, motivation, volition, and course interest. The research was conducted over an 11-week semester with 122 undergraduate online learners within two groups. One group received a traditional e-course, while the other group was offered the course with extra motivational strategies derived from the ARCS-V model. The results revealed that the group who used motivational strategies showed significantly higher gains in motivation, academic performance, and course interest scores. However, there were no significant differences between the groups regarding the volition. Furthermore, the motivation and interest variables were measured with Attention, Relevance, Confidence, and Satisfaction subscales of the ARCS-V model. In terms of interest variable, there was only a statistically significant difference on the Attention subscale. Regarding motivation variable, the results also showed a statistically significant difference on the attention, confidence, and satisfaction subsections of the ARCS-V model. The findings of the present study offer insights into ARCSV model-based research by examining the effects of the model as a valid and reliable framework for online learning environments. The implications and directions for future research are then discussed.  相似文献   
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