Turkish Electro Technology (Turkey)

Abstract Studies for the prevention of bird-induced malfunctions have been examined in the literature. In studies in the literature, some precautions have been taken to prevent birds from being placed in undesirable dangerous spots on conductors and poles. It has been observed that some of the measures are efficient and some are inefficient. In this direction, a number of measures have been taken to Turkish Transmission Network.When evaluated in terms of the number of individuals and wing spans in Türkiye, storks and seagulls are expected to cause the most malfunctions in OHLs. However, it has been observed that the habitats of seagulls are generally near the sea. It has been observed that storks use OHLs and poles on their migration routes, nesting and resting. It has been determined to the degree that storks are mostly responsible for bird-related malfunctions. Turkish Electricity Transmission Corporation has taken various measures to reduce bird-related faults in OHLs. Sheet galvanized metal assembly was carried out in May 2019. Sheet plates are mounted horizontally (flat) on the middle phase console of the poles. As a result of the studies, it was observed that although horizontally mounted galvanized sheets did not prevent nesting, the number of openings of bird-borne OHLs decreased by a minimum of 63 percent and a maximum of 100 percent.

Crew fatigue management is a critical aspect of airline operations, and layover scheduling plays a key role in ensuring the well-being of flight crew members. The increasing complexity of airline networks and availability of multiple hotels at stations necessitates the development of a framework leveraging efficient assignment of crew to the hotels. Besides efficiency, there are pre-defined rules that should be considered such as group-based assignment and maximum quota. In order to efficiently handle the assignment process, this study proposes a novel optimization framework with Mixed Integer Programming (MIP) formulation that ensures compliance with the associated rules. Meanwhile, the proposed optimization model prioritizes fairness among the hotels at the same station. To validate the effectiveness of the proposed approach, an extensive set of experiments are conducted using real-world airline data and the results are analyzed thoroughly. The experiments depict that the proposed optimization model can be solved efficiently within a short time frame, making it suitable for large-scale airline operations.

Abstract As renewable energy integration grows, managing its intermittent nature has become a key challenge for system operators. Energy storage, especially Battery Energy Storage Systems (BESS), helps address this but adds complexity—particularly in hybrid facilities. Clear grid codes are essential to ensure stability and smooth integration. While Türkiye’s Transmission System Operator (TEİAŞ) had established Low Voltage Ride Through (LVRT) requirements for wind and solar, BESS-specific criteria were only introduced in late 2024. Since introduced criteria demanded real-time testing to validate BESS performance during faults, this study explores new LVRT and fault response requirements for standalone and hybrid BESS in Türkiye’s transmission grid. Through the simulations regions were selected based on short-circuit power variability, and using DigSILENT PowerFactory software, BESS responses under different fault scenarios are analyzed. The results inform a nationwide framework for BESS fault ride-through capabilities.

Cavitation wear and hydraulic efficiency decrease in hydroelectric power plants have frequently been the subject of various research and studies. A hydroelectric power plant built on the Kızılırmak River in Türkiye started operating in 1960 and has not been subjected to any large-scale rehabilitation work other than general maintenance until today. The power plant has 4 Francis-type turbines, each with a power of 32 MW. Due to cavitation wear of turbine runners over the years, performance loss, vibration, and noise problems have arisen. Moreover, the maximum turbine hydraulic efficiency, which was 92% in 1960, the year the power plant was commissioned, decreased to 87.9% according to the efficiency measurements carried out at the power plant in 2020. In this study, Computational Fluid Dynamics (CFD) analyses were accomplished with Reynolds averaged Navier Stokes (RANS) calculations for the redesign of the Francis-type turbine runner and finally checked by a model test according to IEC 60193. It was observed that the model test and CFD results were close to each other, especially at the best efficiency point. The maximum turbine hydraulic efficiency, which was calculated as 94.95% as a result of CFD analysis at the nominal head, was calculated as 95.19% by the model test. The x-blade shape created in the redesigned turbine runner blades ensured homogeneous pressure distribution and increased the hydraulic efficiency significantly.

Abstract Ground motion intensity measures (IMs) possess a significant role in earthquake engineering, especially during ground motion selection for nonlinear response history analyses and dynamic shake table tests as well as for probabilistic seismic engineering. Conventional IMs are not capable of accounting for the duration-related cumulative plastic damage, the frequency content of the ground motions, and the hysteretic behavior of the structural members which can be considered inherently by seismic energy-based IMs. However, many efforts have been paid for conventional IMs to relate them to the structural response. To benefit from these efforts, an empirical correlation study between energy-based and conventional IMs is required. To this end, constant ductility seismic input energy and hysteretic energy imparted to diverse single-degree-of-freedom (SDoF) systems were calculated for near-field earthquake records. The empirical correlations of the energy-based IMs with conventional spectrum-based, peak amplitude-based and cumulative-based IMs have been investigated based on the response history analyses. Further, predictive models between energy parameters and spectral acceleration were suggested considering different constant ductility levels. Hence, ground motion characteristics reflected by the input and hysteretic energy can be explicitly considered in performance-based earthquake engineering applications.

The purpose of this study is to examine the school administrators and Generation Z’s perspectives towards each other. The conflict between school administrators and the emerging generation has always been a hot-debate research topic, and it is undeniable that each generation with new defining characteristics make this subject to be worthwhile to re-consider and re-discuss. For this research, from various schools in Istanbul, Kadikoy province, 15 different school administrators and 20 different students of Z generation which were born 2000 and after were volunteered to participate to the research group. This study employed phenomenology pattern and semi- structured negotiation for data collection, and the analysis of the data has been done by using NVIVO 10 program. The study revealed that there are numerous factors that affect the school administrator’s lives: new demands and challenges emerging with new generation, the adaptation problem to the modern instructional technologies and computer-aided teaching system, the role ambiguity, parent’s approach and outside relations influence quality and school management adversely. On the other hand, the analysis of Generation Z student’s perspective brings up a new perspective to the issue of generation gap. From their perspective, the school administrators fail to act in accordance with the changing time and its demands. Most important of all, the generation gap causes the problem of communication, empathy and identification, and this has a decisive, particularly negative influence on their perspective of school life and school administrators. In this study, expectations, responses and critical insights are examined from the lenses of school administrators and students in a way to provide recommendations that could be remedy for the concerns of the school administrators and Generation Z students not only in theory but also in practice.