Browsing by Author "Erdogan, N."

Now showing 1 - 5 of 5

Open Access
Beyond tradition and modernity: digital shadow theater
(M I T Press, 2000) Güdükbay, Uğur; Erol, F.; Erdogan, N.
Open Access
Defining innovation literacy: do robotics programs help students develop innovation literacy skills?
(Yıldız Technical University, 2013-04-10) Erdogan, N.; Corlu, M. S.; Capraro, R. M.
There has been an invalidated belief among educators that the robotics activities would improve the innovation capacities of students. The current study addressed the need to conceptualize the innovation literacy idea while the specific purpose of the study was to determine the effectiveness of a robotics program designed for improving the innovation literacy skills of economically disadvantaged students from underrepresented groups. Participants of the study were 11th grade students from an inner city charter school in Texas (N = 31; 15 female, 23 African American, and 8 Hispanic). In this quantitative study, the paired sample t-test showed statistically significant improvement in science literacy skills of Hispanic students and mathematics and science literacy skills of African American students. The findings implied that more controlled learning environments for students from underrepresented groups would be beneficial.
Open Access
Distributed Control of PEV Charging Based on Energy Demand Forecast
(IEEE Computer Society, 2018) Kisacikoglu, M. C.; Erden, F.; Erdogan, N.
This paper presents a new distributed smart charging strategy for grid integration of plug-in electric vehicles (PEVs). The main goal is to smooth the daily grid load profile while ensuring that each PEV has a desired state of charge level at the time of departure. Communication and computational overhead, and PEV user privacy are also considered during the development of the proposed strategy. It consists of two stages: 1) an offline process to estimate a reference operating power level based on the forecasted mobility energy demand and base loading profile, and 2) a real-time process to determine the charging power for each PEV so that the aggregated load tracks the reference loading level. Tests are carried out both on primary and secondary distribution networks for different heuristic charging scenarios and PEV penetration levels. Results are compared to that of the optimal solution and other state-of-the-art techniques in terms of variance and peak values, and shown to be competitive. Finally, a real vehicle test implementation is done using a commercial-of-the-shelf charging station and an electric vehicle.
Open Access
A fast and efficient coordinated vehicle-to-grid discharging control scheme for peak shaving in power distribution system
(Springer Heidelberg, 2018) Erdogan, N.; Erden, F.; Kisacikoglu, M.
This study focuses on the potential role of plug-in electric vehicles (PEVs) as a distributed energy storage unit to provide peak demand minimization in power distribution systems. Vehicle-to-grid (V2G) power and currently available information transfer technology enables utility companies to use this stored energy. The V2G process is first formulated as an optimal control problem. Then, a two-stage V2G discharging control scheme is proposed. In the first stage, a desired level for peak shaving and duration for V2G service are determined off-line based on forecasted loading profile and PEV mobility model. In the second stage, the discharging rates of PEVs are dynamically adjusted in real time by considering the actual grid load and the characteristics of PEVs connected to the grid. The optimal and proposed V2G algorithms are tested using a real residential distribution transformer and PEV mobility data collected from field with different battery and charger ratings for heuristic user case scenarios. The peak shaving performance is assessed in terms of peak shaving index and peak load reduction. Proposed solution is shown to be competitive with the optimal solution while avoiding high computational loads. The impact of the V2G management strategy on the system loading at night is also analyzed by implementing an off-line charging scheduling algorithm.
Open Access
High transparent, low surface resistance ZTO/Ag/ZTO multilayer thin film electrodes on glass and polymer substrates
(Elsevier, 2021-02-02) Ekmekcioglu, M.; Erdogan, N.; Astarlıoğlu, Aziz Taner; Yigen, S.; Aygun, G.; Ozyuzer, L.; Ozdemir, M.
Zinc tin oxide (ZTO)/Ag/ZTO multilayer thin films were grown by direct current (DC) magnetron sputtering technique at room temperature on soda lime glass (SLG) and different polymer substrates such as polycarbonate (PC) and polyethylene terephthalate (PET) for transparent conductive electrode (TCE) applications. The effect of substrate on the structural, optical and electrical characteristics of ZTO/Ag/ZTO multilayers was investigated. All prepared ZTO/Ag/ZTO films presented amorphous structure as expected from room temperature deposition process and smooth surface quality with very low surface roughness. We found that ZTO/Ag/ZTO multilayer films grown on SLG, PET and PC substrates have very high optical transmission and low surface resistance. Moreover, after ZTO/Ag/ZTO multilayer thin film deposition on polymer substrates, the optical transmission was found to be enhanced because the higher absorption due to Ag layer is compensated by lower reflectance. Our results suggest that ZTO/Ag/ZTO multilayer thin films on any substrate can be a promising alternative to indium tin oxide (ITO) films as a cost-effective, indium-free, flexible and transparent electrode for various applications.