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Robust And Efficient Ebg-Backed Wearable Antenna For Ism Applications, Ayesha Saeed, Asma Ejaz, Humayun Shahid, Yasar Amin, Hannu Tenhunen Jan 2021

Robust And Efficient Ebg-Backed Wearable Antenna For Ism Applications, Ayesha Saeed, Asma Ejaz, Humayun Shahid, Yasar Amin, Hannu Tenhunen

Turkish Journal of Electrical Engineering and Computer Sciences

A structurally compact, semiflexible wearable antenna composed of a distinctively miniaturized electromagnetic band gap (EBG) structure is presented in this work. Designed for body-centric applications in the 5.8 GHz band, the design draws heavily from a novel planar geometry realized on Rogers RT/duroid 5880 laminate with a compact physical footprint spanning lateral dimensions of $0.6$$\lambda$$_0$$\times$$0.06$$\lambda$$_0$. Incorporating a 2$\times$2 EBG structure at the rear of the proposed design ensures sufficient isolation between the body and the antenna, doing away with the performance degradation associated with high permittivity of the tissue layer. The peculiar antenna geometry allows for reduced backward radiation and …


Attention Augmented Residual Network For Tomato Disease Detection Andclassification, Getinet Yilma Abawatew, Seid Belay, Kumie Gedamu, Maregu Assefa, Melese Ayalew, Ariyo Oluwasanmi, Zhiguang Qin Jan 2021

Attention Augmented Residual Network For Tomato Disease Detection Andclassification, Getinet Yilma Abawatew, Seid Belay, Kumie Gedamu, Maregu Assefa, Melese Ayalew, Ariyo Oluwasanmi, Zhiguang Qin

Turkish Journal of Electrical Engineering and Computer Sciences

Deep learning techniques help agronomists efficiently identify, analyze, and monitor tomato health. CNN (convolutional neural network) locality constraint and existing small train sample adversely influenced disease recognition performance. To alleviate these challenges, we proposed a discriminative feature learning attention augmented residual (AAR) network. The AAR network contains a stacked pre-activated residual block that learns deep coarse level features with locality context, whereas the attention block captures salient feature sets while maintaining the global relationship in data points, attention features augment the learning of the residual block. We used conditional variational generative adversarial network (CVGAN) image reconstruction network and augmentation techniques …


A Novel Design Of Current Differencing Transconductance Amplifier With Hightransconductance Gain And Enhanced Bandwidth, Shireesh Kumar Rai, Rishikesh Pandey, Bharat Garg, Sujit Patel Jan 2021

A Novel Design Of Current Differencing Transconductance Amplifier With Hightransconductance Gain And Enhanced Bandwidth, Shireesh Kumar Rai, Rishikesh Pandey, Bharat Garg, Sujit Patel

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, transconductance gain of current differencing transconductance amplifier (CDTA) has been boosted by using a novel approach. Transconductance is generally varied by two well-known techniques. In the first technique, bias current of differential pair MOSFETs is varied whereas in the second technique, aspect ratios of differential pair MOSFETs are changed. The drawbacks of first technique are limited range of transconductance and higher power dissipation whereas second technique restricts dynamic range, output swing and bandwidth of CDTA. To overcome these drawbacks, 2 new structures of CDTA, namely high transconductance gain CDTAs (HTG-CDTA-I & HTG-CDTA-II) have been proposed. HTG-CDTA-I utilizes …


Mismatch Error Shaping Of Dac Unit Elements In Multibit $\Delta$$\Sigma$ Modulators Using A Novel Unified Adc/Dac, Leila Sharifi, Omid Hashemipour Jan 2021

Mismatch Error Shaping Of Dac Unit Elements In Multibit $\Delta$$\Sigma$ Modulators Using A Novel Unified Adc/Dac, Leila Sharifi, Omid Hashemipour

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a unified analog to digital converter (ADC) and digital to analog converter (DAC) for multibit $\Delta\Sigma$ modulators. The unified ADC/DAC circuit provides error shaping for mismatches between DAC unit elements. Hence, the dynamic element matching (DEM) circuit or digital calibration is not required resulting in the area and power saving as well as the elimination of the excess loop delay introduced by DEM circuit. Incorporating a 6-bit unified ADC/DAC, the $\Delta\Sigma$ modulator achieves 16.15-bit resolution utilizing only a second order loop filter and oversampling ratio of 40. The proposed modulator is simulated in a 65-nm CMOS process. …


Bioassessment Of Water Quality Of Surface Waters Using Diatom Metrics, Abuzer Çelekli̇, Haciömer Lekesi̇z, Mehmet Yavuzatmaca Jan 2021

Bioassessment Of Water Quality Of Surface Waters Using Diatom Metrics, Abuzer Çelekli̇, Haciömer Lekesi̇z, Mehmet Yavuzatmaca

Turkish Journal of Botany

Bioassessment of surface waters is one of the most important approaches to predict the deterioration of ecosystems and achieve environmental sustainability according to the application of the European Water Framework Directive. The present review emphasizes the importance of the bioassessment of freshwater quality especially running waters based on diatom metrics. Nutrient enrichment and hydromorphological alternation driven by human activities are the main factors for the ecological compromise of freshwater ecosystems. Currently, the bioassessment of the ecological condition of inland water bodies is adopted worldwide. Bioassessment is complementary to physicochemical and hydromorphological data for evaluating the ecological conditions of rivers; however, …


Bioerosional Structures From The Late Pleistocene Coral Reef, Red Sea Coast, Northwest Saudi Arabia, Huri̇ye Demi̇rcan, Abdelbaset El Sorogy, Talal Alharbi Jan 2021

Bioerosional Structures From The Late Pleistocene Coral Reef, Red Sea Coast, Northwest Saudi Arabia, Huri̇ye Demi̇rcan, Abdelbaset El Sorogy, Talal Alharbi

Turkish Journal of Earth Sciences

Herein, 20 ichnospecies belonging to 8 ichnogenera were identified in bivalves, gastropods, and corals (n = 701) from the Late Pleistocene coral reef along the Red Sea coast, northwest Saudi Arabia. The trace fossils were produced by clionid sponges (47.39%), endolithic bivalves (42.17%), polychaete annelids (5.42%), vermetid gastropods (3.81%), and acrothoracican barnacles (1.21%). The recognized ichnotaxa were Entobia geometrica, E. ovula, E. cf. goniodes, E. cf. retiformis, E. cretacea, Entobia isp., Gastrochaenolites torpedo, G. lapidicus, G. cf. dijugus, Gastrochaenolites isp., Oichnus paraboloides, O. simplex, Oichnus isp., Caulostrepsis taeniola, Caulostrepsis isp., Maeandropolydora cf. sulcans, Maeandropolydora isp., Renichnus isp., Centrichnus isp., and …


Interpretation Of Aeromagnetic Data Of The Sivas Basin In The Central Eastern Turkey, Funda Bi̇li̇m, Atti̇la Aydemi̇r Jan 2021

Interpretation Of Aeromagnetic Data Of The Sivas Basin In The Central Eastern Turkey, Funda Bi̇li̇m, Atti̇la Aydemi̇r

Turkish Journal of Earth Sciences

The Sivas Basin is located in the eastern part of the central Anatolia. In this study, aeromagnetic data in the basin and surrounding area are processed and anomalies are interpreted to determine the approximate locations of the causative bodies and reveal their relationship with the tectonic trends. The sedimentary basin is surrounded by strong magnetic anomalies from the south, east, and northeast. The most apparent anomalies are observed in the E-NE of Zara, SW of Divriği, and north of Kangal. These anomalies do not present significant directional change when they are reduced to the pole process. Causative bodies of the …


Formation Of Ti-Rich Bauxite From Alkali Basalt In Continental Margin Carbonates, Payas Region, Se Turkey: Implications For Sea Level Change In The Upper Cretaceous, Hüseyi̇n Öztürk, Nurullah Hani̇lçi̇, Zeynep Cansu, Cem Kasapçi Jan 2021

Formation Of Ti-Rich Bauxite From Alkali Basalt In Continental Margin Carbonates, Payas Region, Se Turkey: Implications For Sea Level Change In The Upper Cretaceous, Hüseyi̇n Öztürk, Nurullah Hani̇lçi̇, Zeynep Cansu, Cem Kasapçi

Turkish Journal of Earth Sciences

The Payas region bauxite deposits occur as a sandwiched layer that is a few kilometers long and an average of 10 m thick between the lower and upper Cretaceous carbonates of the Arabian Platform. The bauxites occur as 2 types, comprising blanket and pocket, are chemically and texturally homogeneous, and have a thrust structure with ophiolitic mélange formations. The bauxite varies in color, from reddish-brown to grayish-green to black, and has a massive, patchy, and very rare oolitic-pisolitic texture. The bauxite mainly consists of diaspore, hematite, rutile, anatase, rare kaolinite, boehmite, and pyrite minerals.The prismatic and lath-shaped euhedral rutile within …


Multiple Fluid-Mineral Equilibria Approach To Constrain The Evolution Of Thermal Watersin The Hisaralan Geothermal Field, Simav Graben, Western Turkey, Ali̇ Gökgöz, Hali̇m Mutlu, Mehmet Özkul, Ali̇ Kami̇l Yüksel Jan 2021

Multiple Fluid-Mineral Equilibria Approach To Constrain The Evolution Of Thermal Watersin The Hisaralan Geothermal Field, Simav Graben, Western Turkey, Ali̇ Gökgöz, Hali̇m Mutlu, Mehmet Özkul, Ali̇ Kami̇l Yüksel

Turkish Journal of Earth Sciences

In this study seasonal changes in the geochemical and stable isotope compositions of Hisaralan thermal waters in Simav Graben, western Turkey, were investigated with regards to a variety of mineral-water interactions and mixing processes. The Hisaralan and Emendere geothermal waters, with temperatures of up to 99 °C, were mostly of Na-HCO3 and Ca-HCO3 types. The δ18O and δ2H values of the Hisaralan waters ranged from -9.32‰ to -8.73‰ and -65.02‰ to -61.10‰, with maximum seasonal differences of 0.3‰ and 1.8‰. The Emendere waters were represented by a more positive range of δ2H values (-54.95‰ to -54.61‰), while their δ18O compositions …


Time Frame For Future Large Earthquakes Near İstanbul Based On East-To-West Deceleratingfailure Of The North Anatolian Fault, Fati̇h Bulut, Asli Doğru Jan 2021

Time Frame For Future Large Earthquakes Near İstanbul Based On East-To-West Deceleratingfailure Of The North Anatolian Fault, Fati̇h Bulut, Asli Doğru

Turkish Journal of Earth Sciences

Large earthquakes that have occurred along the North Anatolian Fault (NAF) were analysed to elaborate the time frame of future large earthquakes near İstanbul. The historical earthquake catalog that was compiled covered 1 nearly complete and 2 fully complete failures of the NAF between 1250 and 2000 AD. These data were used to investigate the space-time systematics of M ≥ 7.0 earthquakes. The catalogue identified an east-to-west decelerating domino-like failure of the NAF. The deceleration starts around the western tip of the 1944 Gerede rupture. This suggested that failure of the remaining unruptured ~250-km section in the west (İstanbul to …


First Report Of Myalinid Bivalves In The Lower Carboniferous Of The Hakkari Basin, Se Turkey: Paleoecologic And Paleogeographic Implications, İzzet Hoşgör Jan 2021

First Report Of Myalinid Bivalves In The Lower Carboniferous Of The Hakkari Basin, Se Turkey: Paleoecologic And Paleogeographic Implications, İzzet Hoşgör

Turkish Journal of Earth Sciences

Knowledge of the Late Paleozoic sedimentary history of the northern Gondwana shelf is advanced by new data from the Şort Dere section (Hakkari Basin). Early Carboniferous myalinid bivalves from the Middle East are reported here for the first time. The pre-Permian basement of the Hakkari Basin consists of a Lower Carboniferous sedimentary sequence including the Köprülü and Belek formations. The Köprülü Formation has yielded rich assemblages of vertebrates and invertebrates. Hitherto myalinid bivalves were unknown from this formation; this paper reports the discovery of small and poorly calcified myaliniform shells from two thin beds in the middle part of the …


Tectonic Geomorphology Of The Yatağan Fault (Muğla, Sw Turkey): Implications For Quantifying Vertical Slip Rates Along Active Normal Faults, Mehran Basmenji, Taylan Sançar, Aynur Di̇kbaş, Sarah Jean Boulton, Hüsnü Serdar Akyüz Jan 2021

Tectonic Geomorphology Of The Yatağan Fault (Muğla, Sw Turkey): Implications For Quantifying Vertical Slip Rates Along Active Normal Faults, Mehran Basmenji, Taylan Sançar, Aynur Di̇kbaş, Sarah Jean Boulton, Hüsnü Serdar Akyüz

Turkish Journal of Earth Sciences

South Western Anatolia is dominated by E-W and NW-SE trending active faults. The dip-slip Yatağan Fault is one of these active structures that trends in a NW direction for ~30 km. To assess the relative tectonic activity of the Yatağan Fault, two geomorphic segments were defined along the fault: the FS-1 (northern segment) and the FS-2 (southern segment). The vertical slip rate pattern of the fault was analyzed using steepness indexes, chi (χ) plots, and log-log slope area graphs. Results of the analyses indicate that the steepness of the streams draining the footwall reveal increasingly higher values downstream along the …


Interpretation Of Magnetic Data Using Boundary Analysis And Inversion Techniques: A Case Study From Gölcük/Isparta (Turkey) Region, Coşkun Sari, Emre Ti̇mur Jan 2021

Interpretation Of Magnetic Data Using Boundary Analysis And Inversion Techniques: A Case Study From Gölcük/Isparta (Turkey) Region, Coşkun Sari, Emre Ti̇mur

Turkish Journal of Earth Sciences

The Gölcük (Isparta) is on the southern side of the city of Isparta in the Mediterranean region of Turkey. The investigation of magnetic field strength variations over subterranean layers may reveal their locations on Earth?s surface and provide physical and geometrical characteristics. Magnetic studies were carried out around Gölcük caldera lake using proton magnetometers to identify subsurface volcanic structures. The acquired data were inverted using four different edge detection algorithms such as analytic signal, tilt angle, theta map, horizontal gradient. Afterwards, the results were used to determine the locations of the anomalous structures. We also used pseudo-gravity and reduction-to-pole techniques …


Recent Earthquake Activity Of March 2021 In Northern Thessaly Unlocks New Scepticism On Faults, Spyros Pavlides, Sotiris Sboras Jan 2021

Recent Earthquake Activity Of March 2021 In Northern Thessaly Unlocks New Scepticism On Faults, Spyros Pavlides, Sotiris Sboras

Turkish Journal of Earth Sciences

This short opinion article presents and highlights new and old problems related to active geological faults, as seismic sources, after the experience of the last March 3 and 4, 2021 (Mw6.3 and Mw6.0, respectively) Tyrnavos-Elassona earthquakes in northern Thessaly, Greece. Although the active faults in the area are very well studied, demonstrating typical geomorphic features that intensely affect the morphological relief, it seems that the earthquakes were produced by unknown faults emerging in the mountainous area (alpine basement). Primary (?) coseismic ruptures, however, were also observed northwards along the Titarissios valley. A geological interpretation of the faulting mechanism is also …


Geothermal Reservoir Rocks Of The Büyük Menderes Graben (Turkey): Stratigraphiccorrelation By A Multiproxy Approach, Dorothee Siefert, Markus Wolfgramm, Thomas Koelbel, Johannes Glodny, Jochen Kolb, Elisabeth Eiche Jan 2021

Geothermal Reservoir Rocks Of The Büyük Menderes Graben (Turkey): Stratigraphiccorrelation By A Multiproxy Approach, Dorothee Siefert, Markus Wolfgramm, Thomas Koelbel, Johannes Glodny, Jochen Kolb, Elisabeth Eiche

Turkish Journal of Earth Sciences

This paper focuses on the correlation of two different marble units from an approximately 3,900 m deep geothermal exploration well (GP-1) in western Turkey by petrographical and geochemical data. Future geothermal exploration drilling in that area will benefit from a better (tectono) stratigraphic correlation and a better definition of the reservoir geometry in the basin. It is an innovative approximation in many settings to correctly correlate marble units without clear stratigraphic markers or fossil record, in particular, when sample material is restricted to cuttings. The most distinctive petrographical and geochemical properties in this study are colour, light transmission along with …


High Heat Generating Granites Of Kestanbol: Future Enhanced Geothermal System (Egs)Province In Western Anatolia, Dornadula Chandrasekharam, Alper Baba Jan 2021

High Heat Generating Granites Of Kestanbol: Future Enhanced Geothermal System (Egs)Province In Western Anatolia, Dornadula Chandrasekharam, Alper Baba

Turkish Journal of Earth Sciences

Although the western Anatolian region is a foci for hydrothermal systems, this region has several high heat-generating granitic intrusive bodies that qualify to be candidates for enhanced geothermal systems (EGS). Considering the future energy requirement, carbon dioxide emissions reduction strategies, food, and water security issues, these granites appear to be the future clean energy source for the country. One such granite intrusive is located in the Kestanbol area in the western Anatolian region. The radioactive heat generation of this 28 Ma old granite varies from 5.25 to 10.38 μW/m3 with a heat flow of 92.47 to 128.61 mW/m 2. These …


Seismic Velocity Characterisation And Survey Design To Assess Co2 Injection Performanceat Kızıldere Geothermal Field, Mahmut Parlaktuna, Şevket Durucan, Burak Parlaktuna, Çağlar Sinayuç, Martijn T.G. Janssen, Erdi̇nç Şentürk, Eri̇nç Tonğiç, Öncü Demi̇rci̇oğlu, Flavio Poletto, Gualtiero Bohm, Cinzia Bellezza, Biancamaria Farina Jan 2021

Seismic Velocity Characterisation And Survey Design To Assess Co2 Injection Performanceat Kızıldere Geothermal Field, Mahmut Parlaktuna, Şevket Durucan, Burak Parlaktuna, Çağlar Sinayuç, Martijn T.G. Janssen, Erdi̇nç Şentürk, Eri̇nç Tonğiç, Öncü Demi̇rci̇oğlu, Flavio Poletto, Gualtiero Bohm, Cinzia Bellezza, Biancamaria Farina

Turkish Journal of Earth Sciences

The noncondensable gases in most geothermal resources include CO2 and smaller amounts of other gases. Currently, the worldwide geothermal power is a small sector within the energy industry, and CO2 emissions related to the utilisation of geothermal resources are consequently small. In some countries, however, such as Turkey and Iceland, geothermal energy production contributes significantly to their energy budget, and their CO2 emissions are relatively significant. SUCCEED is a targeted innovation and research project, which aims to investigate the reinjection of CO2 produced at geothermal power production sites and develop, test, and demonstrate at field scale innovative measurement, monitoring and …


Harcourt Granite Scco2 Water Interaction: A Laboratory Study Of Reactivity Andmodelling Of Hydrogeochemical Processes, Badulla Liyanage Avanthi Isaka, Ranjith Pathegama Gamage Jan 2021

Harcourt Granite Scco2 Water Interaction: A Laboratory Study Of Reactivity Andmodelling Of Hydrogeochemical Processes, Badulla Liyanage Avanthi Isaka, Ranjith Pathegama Gamage

Turkish Journal of Earth Sciences

Batch-type laboratory reactivity experiments and modelling of hydrogeochemical interactions of a granite-scCO2-water system were conducted at 100 °C and 10 MPa in order to evaluate the geochemical and mineralogical responses of the granite to long-term reaction. The laboratory reactivity tests were conducted for a total duration of 70 days, and the continued hydrogeochemical interactions for up to 210 days were determined by geochemical simulations. The reacted granite powder and the residual solutions were subjected to several analytical techniques, including inductively-coupled plasma optical emission spectrometry (ICP-OES), X-ray diffraction (XRD), scanning electron microscopy (SEM) and pH measurements, in order to characterise the …


Numerical Modeling Of Fluid Flow And Heat Transfer In Kurşunlu Geothermal Field-Kgf(Salihli, Manisa / Turkey), Ali̇ Toygar Akar, Ünsal Gemi̇ci̇, Adi̇le Meli̇s Somay Altaş, Gülteki̇n Tarcan Jan 2021

Numerical Modeling Of Fluid Flow And Heat Transfer In Kurşunlu Geothermal Field-Kgf(Salihli, Manisa / Turkey), Ali̇ Toygar Akar, Ünsal Gemi̇ci̇, Adi̇le Meli̇s Somay Altaş, Gülteki̇n Tarcan

Turkish Journal of Earth Sciences

Nowadays, the need for energy is increasing more and more. It is more difficult to acquire new resources in various fields than to preserve existing energy resources. Although Turkey is a very rich state in terms of various energy resources, misuse of these resources can even lead to conflicts that may occur between the states in forthcoming years. In today's economic conditions, we can only protect our energy resources with the correct way of management. In this context, it is very important to reveal the mechanisms that make up the geothermal systems, which are very common in Western Anatolia. In …


Simulation And Parametric Study On A Novel Modified Kalina Cycle, Guobin Lei, Jun Zhou, Shengchao Shi, Fuzhi Qi, Jiawei Xu, Jie Peng, Jiaqi Zhang, Dongxi Liu, Qingyao Meng Jan 2021

Simulation And Parametric Study On A Novel Modified Kalina Cycle, Guobin Lei, Jun Zhou, Shengchao Shi, Fuzhi Qi, Jiawei Xu, Jie Peng, Jiaqi Zhang, Dongxi Liu, Qingyao Meng

Turkish Journal of Earth Sciences

To improve the utilization rate of hot dry rock resources, it is necessary to recover the energy of geothermal tailwater and improve the net output work. An improved ammonia-water power cycle is proposed based on the Kalina cycle. Taking the geothermal parameters of the Husavik Power Plant in Iceland as the prototype (the water temperature of the geothermal well is 122 °C, and the tailwater temperature is 80 °C), the numerical simulation of the modified Kalina cycle is carried out by using Engineering Equation Solver software. The result shows that the net power output of the modified Kalina cycle increases …


Use Of Geothermal Resources In Konya Plain Project (Kop) Region For Tourism, Healthpurposes, Agricultural, Industrial And Distict Heating, Bariş Çarikci, Merve Sefa, Kevser Akmaz, Ayşe Kandemi̇r, Feza Şen, Hasan Hüseyi̇n Öztürk Jan 2021

Use Of Geothermal Resources In Konya Plain Project (Kop) Region For Tourism, Healthpurposes, Agricultural, Industrial And Distict Heating, Bariş Çarikci, Merve Sefa, Kevser Akmaz, Ayşe Kandemi̇r, Feza Şen, Hasan Hüseyi̇n Öztürk

Turkish Journal of Earth Sciences

This study has been prepared in accordance with the objectives of evaluating and developing geothermal resources in order to bring the geothermal resources in the Konya Plain Project (KOP) Region, which includes Aksaray, Kırşehir, Konya, Nevşehir, Niğde and Yozgat provinces, to the country?s economy with maximum capacity, and to develop proposals for investments to be made. The number of overnight stays and the number of tourists outside the region should be increased by utilizing alternative tourism opportunities in the region. Their use in terms of geothermal energy, tourism and health has an important investment and income potential for the region. …


Grey Water Footprint Assessment Of Geothermal Water Resources In The Southeasternanatolia Region, Peli̇n Yapicioğlu, Mehmet İrfan Yeşi̇lnacar Jan 2021

Grey Water Footprint Assessment Of Geothermal Water Resources In The Southeasternanatolia Region, Peli̇n Yapicioğlu, Mehmet İrfan Yeşi̇lnacar

Turkish Journal of Earth Sciences

This paper aimed to determine the grey water footprint (GWF) of geothermal water resources and to investigate the effect of biochar adsorption on grey water footprint in Southeastern Turkey. In this paper, GWF has been calculated in terms of iron (Fe), arsenic (As), manganese (Mn), boron (B), and chrome (Cr) concentrations for fifteen observation geothermal resources located in Southeastern Anatolia Region. In this study, a new approach based on the GWF was developed in order to determine the geothermal water pollution. Grey water footprints related to fifteen geothermal resources were investigated. In the second stage of the study, the effect …


Lithium Extraction From Geothermal Waters; A Case Study Of Ömer-Gecek(Afyonkarahisar) Geothermal Area, Muhammed Fati̇h Can, Can Başaran, Ahmet Yildiz, Müfi̇t Demi̇rkapi Jan 2021

Lithium Extraction From Geothermal Waters; A Case Study Of Ömer-Gecek(Afyonkarahisar) Geothermal Area, Muhammed Fati̇h Can, Can Başaran, Ahmet Yildiz, Müfi̇t Demi̇rkapi

Turkish Journal of Earth Sciences

Lithium (Li) is the lightest metal, has unique physicochemical properties and is the main component of lithium-ion batteries. Rechargeable lithium-ion batteries play a very important role in maximizing the performance of electric devices and vehicles. It is predicted that the metal and mineral demand for lithium-ion batteries will increase 56 times by 2050. In order to meet the increasing demand, in addition to known methods, lithium recovery from geothermal waters has become a very popular research subject. There are abundant geothermal water resources in the world, especially in Turkey and in Afyonkarahisar. The aim of this study is to produce …


Cover And Contents Jan 2021

Cover And Contents

Turkish Journal of Physics

No abstract provided.


Vacuum Polarization Energy Of The Kinks In The Sinh-Deformed Models, Ishmael Takyi, Benedict Barnes, Joseph Ackora-Prah Jan 2021

Vacuum Polarization Energy Of The Kinks In The Sinh-Deformed Models, Ishmael Takyi, Benedict Barnes, Joseph Ackora-Prah

Turkish Journal of Physics

We compute the one-loop quantum corrections to the kink energies of the sinh-deformed $\phi^{4}$ and $\varphi^{6}$ models in one space and one time dimensions. These models are constructed from the well-known polynomial $\phi^{4}$ and $\varphi^{6}$ models by a deformation procedure. We also compute the vacuum polarization energy to the non-polynomial function $U(\phi)=\frac{1}{4}(1-\sinh^{2}\phi)^{2}$. This potential approaches the $\phi^{4}$ model in the limit of small values of the scalar function. These energies are extracted from scattering data for fluctuations about the kink solutions. We show that for certain topological sectors with nonequivalent vacua the kink solutions of the sinh-deformed models are destabilized.


Deriving Weak Deflection Angle By Black Holes Or Wormholes Usinggauss-Bonnet Theorem, Yashmitha Kumaran, Ali̇ Övgün Jan 2021

Deriving Weak Deflection Angle By Black Holes Or Wormholes Usinggauss-Bonnet Theorem, Yashmitha Kumaran, Ali̇ Övgün

Turkish Journal of Physics

In this review, various researches on finding the bending angle of light deflected by a massive gravitating object which regard the Gauss-Bonnet theorem as the premise have been revised. Primarily, the Gibbons and Werner method is studied apropos of the gravitational lensing phenomenon in the weak field limits. Some exclusive instances are deliberated while calculating the deflection angle, beginning with the finite-distance corrections on nonasymptotically flat spacetimes. Effects of plasma medium is then inspected to observe its contribution to the deflection angle. Finally, the Jacobi metric is explored as an alternative method, only to arrive at similar results. All of …


Thermal Sensitivity From Current-Voltage-Measurement Temperaturecharacteristics In Au/N-Gaas Schottky Contacts, Abdulmeci̇t Turut Jan 2021

Thermal Sensitivity From Current-Voltage-Measurement Temperaturecharacteristics In Au/N-Gaas Schottky Contacts, Abdulmeci̇t Turut

Turkish Journal of Physics

We have measured the current?voltage-temperature (I-V-T) characteristics of the Au/n-GaAs/In Schottky barrier diodes (SBDs) to introduce their thermal sensitivity mechanism. The forward bias voltage variation with temperature (thermal sensitivity) of this SBDs has been studied at different constant current levels. The diode showed high and decisive thermal sensitivity up to a current level of 0.10 pA. The bias voltage-temperature (V-T) curves of the SBD have showed an excellent linear behavior at all current levels. The slope dV/dT = ? or the thermal sensitivity coefficient ? from the V-T curves decreased from 3.42 mV/K at 0.10 pA to 1.31 mV/K at …


Distributed Denial Of Service Attack Detection In Cloud Computing Using Hybridextreme Learning Machine, Gopal Singh Kushwah, Virender Ranga Jan 2021

Distributed Denial Of Service Attack Detection In Cloud Computing Using Hybridextreme Learning Machine, Gopal Singh Kushwah, Virender Ranga

Turkish Journal of Electrical Engineering and Computer Sciences

One of the major security challenges in cloud computing is distributed denial of service (DDoS) attacks. In these attacks, multiple nodes are used to attack the cloud by sending huge traffic. This results in the unavailability of cloud services to legitimate users. In this research paper, a hybrid machine learning-based technique has been proposed to detect these attacks. The proposed technique is implemented by combining the extreme learning machine (ELM) model and the blackhole optimization algorithm. Various experiments have been performed with the help of four benchmark datasets namely, NSL KDD, ISCX IDS 2012, CICIDS2017, and CICDDoS2019, to evaluate the …


A Novel Hybrid Global Optimization Algorithm Having Training Strategy: Hybridtaguchi-Vortex Search Algorithm, Mustafa Saka, Meli̇h Çoban, İbrahi̇m Eke, Suleyman Sungur Tezcan, Müslüm Cengi̇z Taplamacioğlu Jan 2021

A Novel Hybrid Global Optimization Algorithm Having Training Strategy: Hybridtaguchi-Vortex Search Algorithm, Mustafa Saka, Meli̇h Çoban, İbrahi̇m Eke, Suleyman Sungur Tezcan, Müslüm Cengi̇z Taplamacioğlu

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a novel hybrid Taguchi-vortex search algorithm (HTVS) is proposed for solving global optimization problems. Taguchi orthogonal approximation and vortex search algorithm (VS) are hybridized in presenting method. In HTVS, orthogonal arrays in the Taguchi method are trained and obtained better solutions are used to find global optima in VS. Thus, HTVS has better relation between exploration and exploitation, and it exhibits more powerful approximation to find global optimum value. Proposed HTVS algorithm is applied to sixteen well-known benchmark optimization test functions with different dimensions. The results are compared with the Taguchi orthogonal array approximation (TOAA), vortex search …


A Novel Approach For Intrusion Detection Systems: V-Ids, Kenan İnce Jan 2021

A Novel Approach For Intrusion Detection Systems: V-Ids, Kenan İnce

Turkish Journal of Electrical Engineering and Computer Sciences

An intrusion detection system (IDS) is a security mechanism that detects abnormal activities in a network. An ideal IDS must detect intrusion attempts and maybe categorize them for further research and keep false-positive analysis at a very low level. IDSs are used in the analysis of network traffic data at all sizes. Studies on this subject focused on machine learning techniques. Even though the performance rates are high, it is seen that processes such as data understanding, preprocessing, and consistency tests are time-consuming and laborious. For this reason, the use of deep learning (DL) models that automatically perform the mentioned …