06. İYTE Araştırma Merkezleri / IZTECH Research Centers

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Citation - Scopus: 19
Application of Geothermal Energy and Its Environmental Problems in Turkey
(Inderscience Enterprises Ltd., 2015-09) Baba, Alper; Baba, Alper; 03.03. Department of Civil Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
Human beings have been benefiting from geothermal energy for different uses since the dawn of the civilisation in many parts of the world. One of the earliest uses of geothermal energy was for heating and it was used extensively by Romans in Turkey. The Aegean region is favoured by a large number of thermal springs known since ancient times. However, it was first in the 20th century that geothermal energy was used on a large scale for direct use and electricity generation. The country's installed heat capacity is 2,705 MWt for direct use and 322.39 MWe for power production. In parallel to developing geothermal energy applications in Turkey, many sites are now experiencing problems such as water contamination associated with geothermal fluid. Especially, the high temperature solution of elements and compounds, causes operational limitations in geothermal power plants. These limitations are due to the severe scaling and corrosion of geothermal fluid. Copyright © 2015 Inderscience Enterprises Ltd.
Citation - WoS: 4
Citation - Scopus: 4
Are Soil and Geology Characteristics Considered in Urban Planning? an Empirical Study in Izmir (turkiye)
(MDPI, 2023) Salata, Stefano; Uzelli, Taygun; Uzelli, Taygun; Salata, Stefano; 02.03. Department of City and Regional Planning; 01.01. Units Affiliated to the Rectorate; 01. Izmir Institute of Technology; 02. Faculty of Architecture
It is well acknowledged that sustainable soil management can play a crucial role in reducing the vulnerability of urban areas, but are soil characteristics properly evaluated in the decision-making process concerning urbanization? Within this work, we conducted an analysis of the land-use change trends in the city of Izmir (Turkey). We made an extended and detailed analysis of the urbanization processes between 2012 and 2018 in a geographic information system environment (Esri ArcGIS 10.8.1 and ArcGIS Pro 3.0). Then, we superimposed by spatial overlay different soil characteristics: land capability, hydraulic conductibility, soil groups, and fault lines. We discovered that although there is a joint agreement on soil and its geological importance in reducing urban vulnerabilities to flooding, urban heat islands, agricultural production, or earthquakes, there is scarce knowledge of its characteristics to inform land-use planning. This work sheds some light on how newly developed areas are planned without proper consideration of soil properties, following a fuzzy and irrational logic in their distribution. Results encourage the utilization and inclusion of soil knowledge to support the decision-making process concerning urban transformation to achieve more resilient and less vulnerable urban systems.
Citation - WoS: 50
Citation - Scopus: 54
Assessment of Different Nanofiltration and Reverse Osmosis Membranes for Simultaneous Removal of Arsenic and Boron From Spent Geothermal Water
(Elsevier, 2021) Jarma, Yakubu A.; Baba, Alper; Karaoğlu, Aslı; Tekin, Özge; Baba, Alper; Ökten, H.Eser; Tomaszewska, Barbara; Kabay, Nalan; 03.03. Department of Civil Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
One of the factors that determine agricultural crops’ yield is the quality of water used during irrigation. In this study, we assessed the usability of spent geothermal water for agricultural irrigation after membrane treatment. Preliminary membrane tests were conducted on a laboratory-scale set up followed by mini-pilot scale tests in a geothermal heating center. In part I, three commercially available membranes (XLE BWRO, NF90, and Osmonics CK- NF) were tested using a cross-flow flat-sheet membrane testing unit (Sepa CF II, GE-Osmonics) under constant applied pressure of 20 bar. In part II, different spiral wound membranes (TR-NE90-NF, TR-BE-BW, and BW30) other than the ones used in laboratory tests were employed for the mini-pilot scale studies in a continuous mode. Water recovery and applied pressure were maintained constant at 60% and 12 bar, respectively. Performances of the membranes were assessed in terms of the permeate flux, boron and arsenic removals. In laboratory tests, the permeate fluxes were measured as 94.3, 87.9, and 64.3 L m?2 h?1 for XLE BWRO, CK-NF and NF90 membranes, respectively. The arsenic removals were found as 99.0%, 87.5% and 83.6% while the boron removals were 56.8%, 54.2%, and 26.1% for XLE BWRO, NF90 and CK-NF membranes, respectively. In field tests, permeate fluxes were 49.9, 26.8 and 24.0 L m?2 h?1 for TR-NE90-NF, BW30-RO and TR-BE-BW membranes, respectively. Boron removals were calculated as 49.9%, 44.1% and 40.7% for TR-BE-BW, TR-NE90-NF and BW30-RO membranes, respectively. Removal efficiencies of arsenic in mini-pilot scale membrane tests were all over 90%. Quality of the permeate water produced was suitable for irrigation in terms of the electrical conductivity (EC) and the total dissolved solids (TDS) for all tested membranes with respect to guidelines set by the Turkish Ministry of Environment and Urbanisation (TMEU). However, XLE BWRO, CK-NF and NF90 membranes failed to meet the required limits for irrigation in terms of boron and arsenic concentrations in the product water. The permeate streams of TR-BE-BW, TR-NE90-NF and BW30-RO membranes complied with the irrigation water standards in terms of EC, TDS and arsenic concentration while boron concentration remained above the allowable limit. © 2020 Elsevier B.V.
Citation - WoS: 30
Citation - Scopus: 35
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.; 01. Izmir Institute of Technology
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.
Citation - WoS: 4
Citation - Scopus: 4
Breakthrough Curve Analysis of Phosphorylated Hazelnut Shell Waste in Column Operation for Continuous Harvesting of Lithium From Water
(Elsevier, 2024) Recepoğlu, Yaşar Kemal; Recepoğlu, Yaşar Kemal; Arar, Ozguer; Yüksel Özşen, Aslı; Yuksel, Asli; 03.02. Department of Chemical Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
In batch-scale operations, biosorption employing phosphorylated hazelnut shell waste (FHS) revealed excellent lithium removal and recovery efficiency. Scaling up and implementing packed bed column systems necessitates further design and performance optimization. Lithium biosorption via FHS was investigated utilizing a continuous-flow packed-bed column operated under various flow rates and bed heights to remove Li to ultra-low levels and recover it. The Li biosorption capacity of the FHS column was unaffected by the bed height, however, when the flow rate was increased, the capacity of the FHS column decreased. The breakthrough time, exhaustion time, and uptake capacity of the column bed increased with increasing column bed height, whereas they decreased with increasing influent flow rate. At flow rates of 0.25, 0.5, and 1.0 mL/min, bed volumes (BVs, mL solution/mL biosorbent) at the breakthrough point were found to be 477, 369, and 347, respectively, with the required BVs for total saturation point of 941, 911, and 829, while the total capacity was calculated as 22.29, 20.07, and 17.69 mg Li/g sorbent. In the 1.0, 1.5, and 2.0 cm height columns filled with FHS, the breakthrough times were 282, 366, and 433 min, respectively, whereas the periods required for saturation were 781, 897, and 1033 min. The three conventional breakthrough models of the Thomas, Yoon-Nelson, and Modified Dose-Response (MDR) were used to properly estimate the whole breakthrough behavior of the FHS column and the characteristic model parameters. Li's extremely favorable separation utilizing FHS was evidenced by the steep S-shape of the breakthrough curves for both parameters flow rate and bed height. The reusability of FHS was demonstrated by operating the packed bed column in multi-cycle mode, with no appreciable loss in column performance.
Citation - WoS: 11
Citation - Scopus: 10
Cfd Characteristics of Refrigerated Trailers and Improvement of Airflow for Preserving Perishable Foods
(MDPI, 2019) Yildiz,T.
When preserving perishable goods, maintaining a constant temperature over the cold supply chain is essential. Therefore, refrigerated vehicles are an important part of the cold supply chain system. However, many traditional refrigerated cargo systems are not designed to support the homogeneity of the temperature inside cargo trailers. Indeed, refrigerating equipment is usually placed on one side of transportation systems as this is considered to be more practical. Such a configuration thus leads to significant temperature differences in the two distinct parts of a refrigerated cargo trailer, which might affect the quality, safety, and shelf life of perishable foods. This research aims to improve the temperature distribution of refrigerated trailers. In this study, it is highlighted that in the most commonly used traditional refrigerated trailer models, lower air velocity and higher product temperature are observed at the rear. There is also a partial product chilling risk at the front of the refrigerated trailer. This study investigates and reports significant differences among the three airflow design models of refrigerated cargo systems by applying turbulence flow, heat, and mass transfer models. The analyses of these three models reveal that significant improvement could be achieved by applying the proper arrangements of inlets on the ceiling of the trailer body. © 2019 by the author.
Citation - WoS: 4
Citation - Scopus: 10
Characterization of Sb Scaling and Fluids in Saline Geothermal Power Plants: a Case Study for Germencik Region (büyük Menderes Graben, Turkey)
(Pergamon-Elsevier Science Ltd, 2021) Tonkul, Serhat; Demir, Mustafa Muammer; Baba, Alper; Tonkul, Serhat; Demir, Mustafa M.; Baba, Alper; Regenspurg, Simona; 03.06. Department of Energy Systems Engineering; 03.03. Department of Civil Engineering; 03.09. Department of Materials Science and Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
Turkey is located on the seismically active Alpine-Himalayan belt. Although tectonic activity causes seismicity in the Anatolian plate, it also constitutes an important geothermal energy resource. Today, geothermal energy production is heavily concentrated in Turkey's Western Anatolia region. Graben systems in this region are very suitable for geothermal resources. The Buyuk Menderes Graben (BMG) is an area of complex geology with active tectonics and high geothermal potential power. Germencik (Aydin) is located in the BMG, where the geothermal waters include mainly Na-Cl-HCO3 water types. This study examined the stibnite scaling formed in the preheater system of the Germencik Geothermal Field (GGF). The formation of the stibnite scaling on the preheater system dramatically reduces the energy harvesting of the GGF. Considering the stibnite scaling in the surface equipment, the optimum reinjection temperature was determined as 95 degrees C to prevent stibnite scaling in the GGF.
Citation - WoS: 71
Citation - Scopus: 77
A Comparative Study on Exergetic Performance Assessment for Drying of Broccoli Florets in Three Different Drying Systems
(Taylor and Francis Ltd., 2010-02) İçier, Filiz; Hancıoğlu, Ebru; Çolak, Neslihan; Erbay, Zafer; Hancıoğlu Kuzgunkaya, Ebru; Hepbaşlı, Arif; 01. Izmir Institute of Technology
This article deals with the exergy analysis and evaluation of broccoli in three different drying systems. The effects of drying air temperature on the exergy destruction, exergy efficiency, and exergetic improvement potential of the drying process were investigated. The exergy destruction rate for the drying chamber increased with the rise in the drying air temperature at 1.5 m/s, both in the tray and the heat pump dryer. The highest exergy efficiency value was obtained as 90.86% in the fluid bed dryer in comparison to the other two drying systems and the improvement potential rate was the highest in the heat pump dryer during drying of broccoli at the drying air temperature of 45°C and the drying air velocity of 1.0 m/s. © 2010 Taylor & Francis Group, LLC.
Citation - WoS: 41
Citation - Scopus: 58
Current Status and Perspectives of Protease Inhibitors and Their Combination With Nanosized Drug Delivery Systems for Targeted Cancer Therapy
(Dove Medical Press Ltd, 2021) Rudzinska, Magdalena; Dağlıoğlu, Cenk; Dağlıoğlu, Cenk; Savvateeva, Lyudmila, V; Kaci, Fatma Necmiye; Antoine, Rodolphe; Zamyatnin, Andrey A., Jr.; 04.03. Department of Molecular Biology and Genetics; 04. Faculty of Science; 01. Izmir Institute of Technology
In cancer treatments, many natural and synthetic products have been examined; among them, protease inhibitors are promising candidates for anti-cancer agents. Since dysregulated proteolytic activities can contribute to tumor development and metastasis, antagonization of proteases with tailored inhibitors is an encouraging approach. Although adverse effects of early designs of these inhibitors disappeared after the introduction of next-generation agents, most of the proposed inhibitors did not pass the early stages of clinical trials due to their nonspecific toxicity and lack of pharmacological effects. Therefore, new applications that modulate proteases more specifically and serve their programmed way of administration are highly appreciated. In this context, nanosized drug delivery systems have attracted much attention because preliminary studies have demonstrated that the therapeutic capacity of inhibitors has been improved significantly with encapsulated formulation as compared to their free forms. Here, we address this issue and discuss the current application and future clinical prospects of this potential combination towards targeted protease-based cancer therapy.
Citation - WoS: 51
Citation - Scopus: 60
Desalination: From Ancient To Present and Future
(MDPI, 2021) Angelakis, Andreas N.; Baba, Alper; Valipour, Mohammad; Choo, Kwang-Ho; Ahmed, Abdelkader T.; Baba, Alper; Kumar, Rohitashw; Toor, Gurpal S.; 03.03. Department of Civil Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
Water is life, and without water, there would be no civilizations and a vacant Earth. Water is considered an abundant natural resource on the earth. Water covers 3/4 of the surface. However, 97% of the available water on the earth is salty oceanic water, and only a tiny fraction (3%) is freshwater. This small portion of the available water supplies the needs of humans and animals. However, freshwater exists in underground, rivers, and lakes and is insufficient to cover all the world's water demands. Thus, water saving, water reuse, rainwater harvesting, stormwater utilization, and desalination are critical for maintaining water supplies for the future of humanity. Desalination has a long history spanning centuries from ancient times to the present. In the last two decades, desalination has been rapidly expanding to meet water needs in stressed water regions of the world. Yet, there are still some problems with its implementation in several areas of the world. This review provides a comprehensive assessment of the history of desalination for wiser and smarter water extraction and uses to sustain and support the water needs of the earth's inhabitants.
Citation - WoS: 10
Citation - Scopus: 15
Design and Analysis of a Lightweight Composite Shipping Container Made of Carbon Fiber Laminates
(MDPI, 2019) Yildiz,T.
The literature indicates that a 20% reduction in the weight of empty 40-foot shipping containers would result in $28 billion of fuel savings, along with a 3.6 exajoule reduction in the energy demand over containers’ 15-year lifetime. Decreasing the energy demand and thereby greenhouse gas emissions by utilizing lightweight shipping containers has been an unexplored strategy. In this regard, this study investigates the possibility of further reducing the weight of an empty container without compromising the structural integrity, strength, and function of a traditional steel container. This research finds that up to an 80% reduction in weight is possible by producing shipping containers with composite materials. This research presents the new design of a 40-foot container made of carbon fiber laminates. The tare weight of a traditional 40-foot shipping container is around 3750 kg. On the contrary, in this research, the weight of a composite design of the same container is calculated to be around 822 kg. Additional tests with various loads, such as lifting the container and stacking loads onto the composite container, are performed to explore the strength and buckling issues of the design presented in this study. The analyses reveal that the composite shipping container is a highly promising candidate for reducing greenhouse gas emissions, providing fuel savings and thus reducing the operational costs of transportation. © 2019 by the author.
Citation - WoS: 31
Citation - Scopus: 35
Distribution of Geothermal Arsenic in Relation To Geothermal Play Types: a Global Review and Case Study From the Anatolian Plate (turkey)
(Elsevier, 2021) Baba, Alper; Uzelli, Taygun; Uzelli, Taygun; Baba, Alper; Sözbilir, Hasan; 03.03. Department of Civil Engineering; 01.01. Units Affiliated to the Rectorate; 01. Izmir Institute of Technology; 03. Faculty of Engineering
Arsenic has a natural cycle as it travels underground. It can mix with geothermal fluid in different ways under the control of magmatic and tectonic processes. Geogenic arsenic is present in many geothermal fields in the world at concentrations above the limits set for human health. The arsenic content of geothermal fluids is also related to the concept of geothermal play type, which forms geothermal systems, because the natural processes that form the geothermal system also control the arsenic cycle. In this study, an attempt is made to explain the relationship between the geothermal play type concept and geothermal arsenic circulation. For this purpose, geothermal field examples are given from around the world and Turkey. The result shows that arsenic concentrations can reach significant levels along with plate tectonic boundaries in the world. When arsenic concentrations were evaluated, the effect of major faults on the Anatolian Plate was clearly seen. Also, in the Anatolian plate where volcanosedimentary units are common, geothermal fluids caused more effective alteration along with structural control and increased arsenic concentrations in geothermal systems. This interaction between structural elements, geothermal fluid, and the arsenic cycle shows that the concept of play type in geothermal systems should also be taken into consideration. It was determined that the places with high arsenic values are located within the convective-non-magmatic extensional geothermal play types such as Western Anatolian Extensional System and the North Anatolian Fault. The concept of play type in geothermal systems includes all systematic and external factors that make up these processes. For this reason, it is very important to evaluate the play type classification together with the arsenic cycle.
Citation - WoS: 3
Citation - Scopus: 6
Effect of High Salinity and Temperature on Water-Volcanic Rock Interaction
(Springer, 2021) Gören, Ayşegül Yağmur; Gören, Ayşegül Yağmur; Topçu, Gökhan; Demir, Mustafa Muammer; Demir, Mustafa M.; Baba, Alper; Baba, Alper; 03.07. Department of Environmental Engineering; 03.03. Department of Civil Engineering; 03.09. Department of Materials Science and Engineering; 03. Faculty of Engineering; 01. Izmir Institute of Technology
In order to understand the processes occurring in natural hydrothermal systems, it was carried out a series of water-volcanic rock interaction studies in the laboratory and an intermediate volcanic rock samples from geothermal production wells in Tuzla geothermal field (TGF) in western Turkey. A high-pressure autoclave was used to conduct water-rock interaction experiments under similar conditions of the field. Rainwater and seawater were treated with volcanic rocks at 140 degrees C (reservoir temperature) and 4.5 bar pressure. The change in the ionic content of the resulting fluids was examined in terms of the type of volcanic rocks and mineral saturation index. The results indicate that talc and diopside minerals in geothermal systems may cause scaling at high temperatures depending on the geothermal fluid and pH.
Citation - WoS: 1
Effect of Ultraviolet B Radiation on the Absorption Characteristics of Various Intraocular Lenses
(S. Karger AG, 2006-12) Koçak, Nilüfer; Kaynak, Süleyman; İlknur, Turna; Özkan, Şebnem; Erdoğan, Gökhan; Çıngıl, Güray
Background: The aim of this study was to determine the effect of ultraviolet B (UVB) exposure on UV filters of various intraocular lenses (IOLs). Methods: Eight samples each of the hydrophobic acrylic, hydrophilic acrylic and silicone IOLs were used. Four IOLs of each type was selected randomly as the control group while the remaining four IOLs of each type were exposed to a UVB dose of 1.4 J/cm2 (2.40 mW/cm2) for 9.45 min, two times with a 4-week interval. IOLs were evaluated for any sign of opacification under microscope weekly. After a follow-up period of 16 weeks, spectrometry for UV filter absorption rates, scanning electron microscopy for deposit formation and energy dispersive X-ray analysis for elemental composition were performed for all IOLs, and findings of the control group IOLs were compared with those of the UVB-exposed IOLs. All these procedures were done at the Department of Ophthalmology, Faculty of Medicine, Dokuz Eylul University. Results: All the IOLs were free of any opacification during the follow-up period. Spectrometric analysis of their UV filters revealed a change in absorption rates in the hydrophilic acrylic and silicone IOLs compared to the control IOLs of the same type. Only the hydrophobic acrylic IOLs preserved the same UV absorption curve after UVB exposure. Conclusion: The pathogenesis of IOL opacification is still undetermined. Some reports claimed that the UV light was the responsible factor. Our experimental study revealed that high doses of UVB did not cause any opacification though they impaired the function of UV filters of the hydrophilic acrylic and silicone IOLs. Copyright © 2007 S. Karger AG.
Citation - WoS: 3
Citation - Scopus: 3
Effects of Different Lipopolysaccharide Preparations on Neutrophil Function in the Fathead Minnow, Pimephales Promelas Rafinesque
(John Wiley and Sons Inc., 2011-11) Jovanovic, B.; Baran, Ezgi; Goetz, F. W.; Palic, D.
The fish innate immune response to pathogensrelies on the adequate function of neu trophilicgranulocytes (Palic´, Andreasen, Herolt, Menzel &Roth 2006). The ability of neutrophils to phago-cytose microor ganisms and cellular debris is essen-tial for normal development an d survival of animalpopulations (Segal 2005). The evaluation of neu-trophil function is valuable for assessing the healthstatus of individuals and fish populations (Smith &Lumsden 1983). Resistance of fishes to septic shockand tolerance to high concentrations of lipopoly-saccharide (LPS) was observed as a major differencebetween mammalian and fish innate immuneresponses (Berczi, Bertok & Bereznai 1966). Thisfunctional difference could be attri buted to severalcostimulatory molecules and intracellular mediatorsbeing absent in fish, but active in mammals duringresponse to LPS stimulation (Iliev, Roach, Mac-kenzie, Planas & Goetz 2005). Most fish do notpossess a Toll-like receptor (TLR) with sequencesimilarity to mammalian TLR4 (Leulier & Lemai-tre 2008) and the ones that do have no ability forTLR4 downstream signalling (Sepulcre, Alcaraz-Perez, Lopez-Munoz, Roca, Meseguer, Cayuela &Mulero 2009). Regardless of the absence andfunctionality of TLR4 and costimulatory molecules,bacterial LPS can induce a robus t inflammatorygene response in innate immune fish cells, but atconcentrations 1000-fold higher than is commonlyobserved in mammalian species ( lgmL)1vs.ng mL)1) (Palic´, Ostojic, Andreasen & Roth2007; Mackenzie, Roher, Boltan˜a & Goetz 2010).In contrast, ultrapure LPS preparations are rela-tively inactive in fish (Iliev et al. 2005).
Citation - WoS: 4
Citation - Scopus: 13
Effects of Seismic Activity on Groundwater Level and Geothermal Systems in İzmir, Western Anatolia, Turkey: the Case Study From October 30, 2020 Samos Earthquake
(TÜBİTAK - Türkiye Bilimsel ve Teknolojik Araştırma Kurumu, 2021) Uzelli, Taygun; Baba, Alper; Bilgiç, Esra; Bilgiç, Esra; Öztürk, Bahadır; Uzelli, Taygun; Baba, Alper; Öztürk, Bahadır; Sözbilir, Hasan; Tatar, Orhan; 01. Izmir Institute of Technology; 03.03. Department of Civil Engineering; 01.01. Units Affiliated to the Rectorate; 03. Faculty of Engineering
The October 30, 2020 Samos earthquake (Mw 6.6) affected the Aegean Sea and environs, caused destruction and loss of life in the city of İzmir located 70 km away from the earthquake epicenter. Before this earthquake, water resources were monitored in the areas of Bayraklı, Gülbahçe, and Seferihisar. For this purpose, 10 groundwater monitoring wells were drilled in the Bayraklı area, where groundwater level, temperature, and electrical conductivity changes were monitored at 1-h intervals in 5 wells. Besides physical parameters such as groundwater levels, temperatures and electrical conductivities, hydrogeochemical cations, and anions measured in the study area. Change in the groundwater levels was observed before, during, and after the Samos earthquake. A trend of rising groundwater level was observed two days before the mainshock, to a height of 10 cm, and the level was maintained till the end of the earthquake. The water levels returned to its original height after about 7 to 10 days of the earthquake. Moreover, electrical conductivity (EC) values were changed because of the interaction with the surrounding rocks and well walls, mixing with different waters during the earthquake shaking. The essential anomalies were observed in the geothermal fields of Gülbahçe and Seferihisar. Due to this earthquake, new geothermal springs emerged along the NE-SW trending Gülbahçe and Tuzla faults, located about 50 to 20 km from the Samos earthquake epicenter, respectively. The new geothermal waters are in Na-Cl composition and similar to other geothermal springs in the region. While the recorded water temperatures in the new geothermal springs vary from 40 to 45 °C in Seferihisar, it was measured between 35 and 40 °C in Gülbahçe. Due to these anomalies, it is found essential to monitor the effect of the earthquake on the physical and chemical characteristics of the groundwater and its usefulness in earthquake predictions.
Citation - WoS: 3
Citation - Scopus: 6
Elemental Analysis of Galium Incanum Sm Subsp Centrale Ehrend by X-Ray Fluorescence Spectroscopy
(Pharmacotherapy Group, 2013-12) Kayalar, Hüsniye; Durmuşkahya, Cenk; Hortooğlu, Zehra Sinem
Purpose: To evaluate the content of trace elements in Galium incanum SM. subsp. centrale Ehrend. Methods: The air-dried aerial parts of the plant material were used and its water extract (2 % w/v infusion) was analysed for trace elements using x-ray fluorescence (XRF) spectrometry. Results: The aqueous extract depicted significant concentrations of macro- and micro-nutrients with heavy metal and metal oxide content of 4.07 - 6.02 and 3.19 - 4.01 % for powdered plant material and water extract, respectively. The contents of Ca (22840 ppm) and K (8204 ppm) were the highest among all the elements while Zn (45.9 ppm) and Fe (328 ppm) were also detected in significant amounts. Zn, Mn and Cu showed the highest content while those of Mg, Al, K, Ca, Fe and P lowest in the water extract. Conclusion: The presence of significant levels of Ca, K, Na, Fe, Zn, Mg, Mn and Cu in G. incanum subsp. centrale showed that this plant has notable nutrient elements. The traditional use of Gallium species as a diuretic may be attributed to its rich content of potassium.
Citation - Scopus: 9
An Empirical Analysis on Logistics Performance and the Global Competitiveness
(Vilnius Gedminas Technical University, 2017) Yıldız, Türkay
Logistics has been identified as an area to build cost and service advantages. Therefore, companies are more focused on customer needs and trying to find ways to reduce costs, improve quality and meet the growing expectations of their clients. Indeed, the global competition has led managers to begin to address the issue of providing more efficient logistics services. In this regard, this paper presents an empirical study on logistics performance and global competitiveness. This paper also identifies the associations between logistics performances and global competitiveness. The results indicate that some variables in global competitiveness scores contribute much higher to the logistics performances than the other variables through analysis. The variables that contribute much higher than the other variables to the logistics performances are shown.
Citation - WoS: 8
Citation - Scopus: 14
An End-To Trainable Feature Selection-Forecasting Architecture Targeted at the Internet of Things
(IEEE, 2021) Nakıp, Mert; Karakayalı, Kubilay; Güzeliş, Cüneyt; Rodoplu, Volkan
We develop a novel end-to-end trainable feature selection-forecasting (FSF) architecture for predictive networks targeted at the Internet of Things (IoT). In contrast with the existing filter-based, wrapper-based and embedded feature selection methods, our architecture enables the automatic selection of features dynamically based on feature importance score calculation and gamma-gated feature selection units that are trained jointly and end-to-end with the forecaster. We compare the performance of our FSF architecture on the problem of forecasting IoT device traffic against the following existing (feature selection, forecasting) technique pairs: Autocorrelation Function (ACF), Analysis of Variance (ANOVA), Recurrent Feature Elimination (RFE) and Ridge Regression methods for feature selection, and Linear Regression, Multi-Layer Perceptron (MLP), Long Short Term Memory (LSTM), 1 Dimensional Convolutional Neural Network (1D CNN), Autoregressive Integrated Moving Average (ARIMA), and Logistic Regression for forecasting. We show that our FSF architecture achieves either the best or close to the best performance among all of the competing techniques by virtue of its dynamic, automatic feature selection capability. In addition, we demonstrate that both the training time and the execution time of FSF are reasonable for IoT applications. This work represents a milestone for the development of predictive networks for IoT in smart cities of the near future.
Citation - WoS: 2
Citation - Scopus: 2
Energy Performance Assessment in Terms of Primary Energy and Exergy Analyses of the Nursing Home and Rehabilitation Center
(SAGE Publications Inc., 2019-12) Hancıoğlu Kuzgunkaya, Ebru; Hancıoğlu, Ebru; 01. Izmir Institute of Technology
This paper concerns with the energy analysis (based on primary energy) and exergy analysis of Narlıdere Nursing Home and Rehabilitation Center (NNHRC) in İzmir, Turkey that was chosen as a sample public building. The Center services as a nursing and rehabilitation center for the aged and it also includes a geriatric division operating as a hospital. The Center was analyzed using the actual energy consumption data derived from several energy audits. Energy efficiency (according to the primary energy ratio) and exergy efficiency of the facility were calculated to be 59% and 14%, respectively. The results have indicated that the exergy efficiencies of space heating and cooling have the lowest values compared with the other units of facility. Specific primary energy consumption and specific exergy consumption of the facility were found to be 271.91 kWh/m2 year and 290.23 kWh/m2 year, respectively. Sustainability index value of the overall NNHRC was found to be 1.621.

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