Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

Browse

Search Results

Now showing 1 - 10 of 18
  • Article
    Citation - WoS: 1
    Citation - Scopus: 2
    Integration of Daylight Use and Analysis in Double Skin Facades: a Literature Review
    (Gazi Universitesi, 2024) Kazanasmaz, Tugce; Ünlütürk, Mustafa Serhan
    Double skin facades (DSF) aim to save energy reducing the heat losses in buildings. They are visually appeal while allowing to use daylight efficiently. Such facade systems can reduce glare and distribute daylight evenly in the interior when compared to conventional facade systems. That is a result of cavities between two glass facades and locating sun shading elements in them, although this system provides a high level of transparency. As their primary purpose of application is to ensure thermal performance and ventilation, most studies in literature have focused on these. This study started with the hypothesis that studies examining daylight performance in DSFs are more limited than studies examining thermal performance and that daylight optimization methods are not used sufficiently in DSFs. In this context, the study aims to analyze studies focusing on daylight performance of DSFs. The review targets results of such current studies to guide future ones providing feedback knowledge. This may help to better technical developments in such facades and make them prevail in constructions or in retrofitting So, it contributes to literature in this sense. Recent studies are shown in tabulated form and interpreted in detail with graphics. considering their methodologies, daylight parameters and findings. Results show that the daylight parameter is one of the most important issues that architects or designers should consider from the moment they start the design, and they should make their designs based on the optimum penetration of daylight into the building. Consequently, this review presents that the use of daylight optimization has started to be used in recent studies dealing with DSFs. A DSF design can optimally get daylight into the interior can be made by using this method more frequently.
  • Article
    Citation - Scopus: 5
    Event Distortion-Based Clustering Algorithm for Energy Harvesting Wireless Sensor Networks
    (Springer, 2022) Al-Qamaji, A.; Atakan, B.
    Wireless sensor networks (WSNs) consist of compact deployed sensor nodes which collectively report their sensed readings about an event to the Base Station (BS). In WSNs, due to the dense deployment, sensor readings can be spatially correlated and it is nonessential to transmit all their readings to the BS. Therefore, for more energy efficient, it is vital to choose which sensor node should report their sensed readings to the BS. In this paper, the event distortion-based clustering (EDC) algorithm is proposed for the spatially correlated sensor nodes. Here, the sensor nodes are assumed to harvest energy from ambient electromagnetic radiation source. The EDC algorithm allows the energy-harvesting sensor nodes to select and eliminate nonessential nodes while maintain an acceptable level of distortion at the BS. To measure the reliability, a theoretical framework of the distortion function is first derived for both single-hop and two-hop communication scenarios. Then, based on the derived theoretical framework, the EDC algorithm is introduced. Through extensive simulations, the performance of the EDC algorithm is evaluated in terms of achievable distortion level, number of alive nodes and harvested energy levels. As a result, EDC algorithm can successfully exploit both the spatial correlation and energy harvesting to improve the energy efficiency while preserving an acceptable level of distortion. Furthermore, the performance comparisons reveal that the two-hop communication model outperforms the single-hop model in terms of the distortion and energy-efficiency. © 2021, The Author(s).
  • Conference Object
    Citation - Scopus: 1
    Daylight Performance and Lighting Energy Savings of Amorphous and Crystalline Silicon Solar Cells in an Architecture Studio
    (IEEE, 2023) Taşer, Aybüke; Kazanasmaz, Zehra Tuğçe
    Semi-transparent photovoltaic (PV) glass increased its popularity due to its energy and environmental advantages, which can generate electricity on-site and utilize natural daylight. They use thin-film solar cells to allow daylight to enter space and generate electrical energy. Crystalline and amorphous silicon (a-Si) solar cells are the most prominent in literature and industry due to their high efficiency and sufficient transparency. This study aims to assess the daylight and lighting energy-saving potential of thin-film crystalline and a-Si photovoltaic glass in an architecture studio in Izmir, Turkey. The simulation engine applied two types of solar cells on existing windows to evaluate the advantage of such glass for daylight performance and lighting energy consumption. Spatial Daylight Autonomy (sDA), a climate-based annual daylight performance metric, evaluates the daylight performance of the studio. Research findings note that such solar cells enhance the visual comfort of occupants and the daylight performance of the studio. In addition, crystalline silicon solar cells can cover the studio's whole lighting loads in the summer and fall seasons and balance them up to 66% and 23% in the spring and winter seasons, respectively. These have higher transmittance and peak power, thus; resulting in higher energy and daylight performance. © 2023 IEEE.
  • Conference Object
    Citation - Scopus: 1
    A Lightweight and Energy Efficient Secrecy Outage Probability-Based Friendly Jamming
    (IEEE, 2023) Yaman, Okan; Ayav, Tolga; Erten, Yusuf Murat
    Third parties and legitimate entities can reach and process users' private data through most wireless networks. However, attackers such as intruders and eavesdroppers may also try to exploit this property in communication. Hence, wireless networks are intrinsically more vulnerable to threats, unlike their wired alternatives. Cryptographic techniques are the conventional approaches to deal with that weakness. Nevertheless, they still need to meet the requirements of contemporary technologies, including IoT nodes with energy and processing power constraints. In that respect, friendly jamming (FJ) is one of the encouraging countermeasures to overcome the mentioned susceptibility since it has an energy-efficient and computation-friendly nature. However, that promising approach brings another challenge, applicability. Although various models exist against this issue, a lightweight scheme compliant with novel technologies is needed. Hence, we propose a more straightforward FJ model evaluated on cellular network-based simulations in this study. Moreover, introducing a lightweight secrecy outage probability definition increases robustness and energy efficiency. © 2023 IEEE.
  • Article
    Citation - WoS: 77
    Citation - Scopus: 95
    Thermal, Daylight, and Energy Potential of Building-Integrated Photovoltaic (bipv) Systems: a Comprehensive Review of Effects and Developments
    (Elsevier, 2023) Taşer, Aybüke; Kundakçı Koyunbaba, Başak; Kazanasmaz, Zehra Tuğçe
    According to energy consumption data of the European Union, buildings account for 40 % of overall energy consumption in all sectors. The rise in building energy demand seriously affects global warming. To reduce demand, buildings must be designed to be energy-efficient. As part of energy-efficiency initiatives, unique systems that employ renewable energy sources should be implemented in buildings. As a new technology, building-integrated photovoltaics is considered an essential technology to achieve this target. Several variables affect the thermal, daylight, and energy performance of building-integrated photovoltaic systems; related to environmental and photovoltaic-related parameters. Thus, the challenges and effects of these variables on the overall performance of these systems should be investigated. This research analyzes building-integrated photovoltaic implemented studies and presents a state-of-art review of recent developments. The study not only summarizes the existing studies developed in this field so far but also analyzes the variables and makes concrete generalizations and inferences. It enables finding gaps and deficiencies in the literature and provides a better understanding of all the variables that affect the performance of building-integrated photovoltaic systems by interpreting the results in detail and representing them graphically instead of only through textual analysis. Results show that building-integrated photovoltaics contribute to constructing a sustainable future for cities. Developments in this industry motivate researchers in this field, whose work will make it easier to cope with future ecological challenges. It helps to build a more sustainable future for society. With new developments, it will be possible to mitigate the effects of future environmental problems.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    EXPERIMENTAL AND ANALYTICAL EXAMINATION OF THE EFFECT OF DOUBLE SKIN FAÇADE SYSTEM ON BUILDING THERMAL PERFORMANCE;
    (Turk Isi Bilimi ve Teknigi Dernegi, 2021) Hülagü,S.; Göksal Özbalta,T.; Başaran,T.
    In this study, heat transfer in conventional single skin façade and double skin façade system was studied experimentally and numerically by using one dimensional time dependent approach and the effects of the façade systems on building energy performance especially heating energy was investigated. In this context, a mathematical model considering user behavior and window aluminum frame element effect was build by zonal analysis method to calculate the heat transfer in single and box type closed cavity double skin façade systems, and build model was experimentally verified. Experimental study was conducted in office spaces having single and double skin façade systems in Ege University, Civil Engineering Building’s south façade in January 2017. Next, verified model was used to study the heat transfer in the façade systems for İzmir’s climatic condition by using monthly average daily data. The change in thermal performance of single and double skin façade systems due to the climatic condition during a year was investigated by using the 10 year average climate data of İzmir (Mediterranean climate). It was found that double skin façade system acts as an insulator preventing extreme indoor temperature values, thus contributing to the indoor comfort level against changing outdoor conditions. ©2021 TIBTD Printed in Turkey.
  • Article
    Citation - WoS: 34
    Citation - Scopus: 41
    Assessment of Geothermal Energy Use With Thermoelectric Generator for Hydrogen Production
    (Pergamon-Elsevier Science LTD, 2021) Hadjiat, M. M.; Hancıoğlu, Ebru; Mraoui, A.; Ouali, S.; Hancıoğlu Kuzgunkaya, Ebru; Salhi, K.; Ouali, A. Ait; Benaouda, N.
    In this work, a new model for producing hydrogen from a low enthalpy geothermal source was presented. Thermal energy from geothermal sources can be converted into electric power by using thermoelectric modules instead of Organic Rankine Cycle (ORC) machines, especially for low geothermal temperatures. This electrical energy uses the water electrolysis process to produce hydrogen. Simulation and experiments for the thermoelectric module in this system were undertaken to assess the efficiency of these models. TRNSYS software is used to simulate the system in Hammam Righa spa, the temperature of this spring is 70 degrees C. Obtained results reveal that in hammam righa spa in Algeria, 0.5652 Kg hydrogen per square meter of thermoelectric generator (TEG) can be produced in one year. (C) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
  • Article
    Citation - WoS: 33
    Citation - Scopus: 41
    Development of a Personalized Thermal Comfort Driven Controller for Hvac Systems
    (Elsevier Ltd., 2021) Turhan, Cihan; Simani, Silvio; Gökçen Akkurt, Gülden
    Increasing thermal comfort and reducing energy consumption are two main objectives of advanced HVAC control systems. In this study, a thermal comfort driven control (PTC-DC) algorithm was developed to improve HVAC control systems with no need of retrofitting HVAC system components. A case building located in Izmir Institute of Technology Campus-Izmir-Turkey was selected to test the developed system. First, wireless sensors were installed to the building and a mobile application was developed to monitor/collect temperature, relative humidity and thermal comfort data of an occupant. Then, the PTC-DC algorithm was developed to meet the highest occupant thermal comfort as well as saving energy. The prototypes of the controller were tested on the case building from July 3rd, 2017 to November 1st, 2018 and compared with a conventional PID controller. The results showed that the developed control algorithm and conventional controller satisfy neutral thermal comfort for 92 % and 6 % of total measurement days, respectively. From energy consumption point of view, the PTC-DC decreased energy consumption by 13.2 % compared to the conventional controller. Consequently, the PTC-DC differs from other works in the literature that the prototype of PTC-DC can be easily deployed in real environments. Moreover, the PTC-DC is low-cost and user-friendly.
  • Conference Object
    Energy-Efficient Resource Allocation for Multiuser Ofdm Wireless Networks
    (Institute of Electrical and Electronics Engineers Inc., 2015) Durbaş, Şükrü; Özbek, Berna
    In the last decades, the energy consumption in wireless communication systems is increasing and becoming a major problem for cellular operators. As a result of that, solutions to increase energy-efficiency (EE) in wireless networks are becoming more popular. Therefore, the resource allocation algorithms that provides EE for multiuser OFDM based wireless networks is presented in this paper. Then, the conventional spectrum-efficient (SE) designs are compared with EE based schemes and EE characteristics of the system has been analyzed. The simulation results show the advantages of EE scheme especially on high channel-gain-to-noise ratio and low number of users cases.
  • Article
    Citation - WoS: 14
    Citation - Scopus: 14
    Thermal Simulation of Retrofits To Existing Mass Housing in Turkey for Energy Efficiency
    (Sila Science, 2011) Yıldız, Yusuf; Durmuş Arsan, Zeynep
    Energy consumption in the existing residential building stock in Turkey is currently excessive. Mass housing, comprising a major portion of the officially-registered residential stock, carries enormous potential for energy savings even in the short run. This paper describes a case study in a mass housing area in Izmir, Turkey, in order to demonstrate the possibility of significant energy savings by implementing case-specific energy-efficient retrofitting scenarios and relating them with the payback periods. Building energy analysis software was used to examine thirteen scenarios consisting of various combinations of four main retrofitting options: addition of extra insulation for building envelope, replacement of existing glazing, regulation of air infiltration rate and indoor set point temperature. These scenarios revealed that annual energy savings of up to 62% are achievable and that the customer payback period for the best retrofitting scenario is 34 years.