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Article Citation - WoS: 45Citation - Scopus: 69Software architecture of the internet of things (IoT) for smart city, healthcare and agriculture: analysis and improvement directions(Springer Heidelberg, 2021) Gavrilovic, Nebojsa; Mishra, AlokInternet of things (IoT) enables organizations to automate the process and improves service delivery through Internet technology and transferring the data at the cloud level. IoT does not allow the use of a universal software architecture for different fields in which it is used, but needs to be adjusted according to the requirements of users. This paper presents an analysis of currently available types of software architectures of the IoT systems in the field of smart cities, healthcare, and agriculture. It provides a proposal for solutions and improvements of different software architecture types, interactions between identified software architecture elements that will provide better performance and simplicity. The novelty of the study is the analysis of different types of IoT software architecture such as: layered, service-oriented and cloud-based software architecture application in these areas of IoT. Based on the analysis, the study proposed the type of software architecture of the IoT system for the relevant area of application (smart city, healthcare, and agriculture). Specific points of research are: analysis of different types of software architecture applied in IoT systems, identification of functionalities available in IoT systems through different types of software architecture, the proposal for enhancement of the above functionalities, and proposal of software architecture that is most relevant to the IoT system of a particular area.Article Citation - WoS: 9Citation - Scopus: 10Influence of Cement Replacement by Calcinated Kaolinitic and Montmorillonite Clays on the Properties of Mortars(Springer Heidelberg, 2023) Al-Noaimat, Yazeed A. A.; Akis, TolgaThis study aims to investigate the decomposition and pozzolanic reactivity of two different clays (kaolinitic and montmorillonite) from different origins and to determine their effects after calcination on the properties of cement mortars when used to replace Portland cement partially. Mineralogical and chemical compositions of the clay samples were determined using XRD (X-ray Diffractometer) and XRF (X-ray Fluorescence) tests, respectively. TG-DTA (Thermogravimetry-Differential Thermal Analyses) was used to determine the temperature profiles and the burning temperatures of the clays. The density and fineness of the burnt clays were also determined. In order to investigate the optimum material properties, different burning temperatures and replacement levels were considered. It was found that for all temperatures, the two burnt clays possess good pozzolanic activity. The highest compressive strength and lowest water absorption capacity were achieved when the clay determined as kaolinitic was burned at 700 & DEG;C and with 10% replacement level. While for the clay determined as montmorillonite, the optimum properties were obtained at 700 & DEG;C with a 20% substitution level. Kaolinite had better pozzolanic reactivity than montmorillonite, achieving higher strength performance with lower water absorption when partially replaced with cement. Moreover, it had compressive strength values even higher than plain cement.Article Citation - WoS: 4Citation - Scopus: 5A Long-Run Convergence Analysis of Aerosol Precursors, Reactive Gases, and Aerosols in the Brics and Indonesia: Is a Global Emissions Abatement Agenda Supported?(Springer Heidelberg, 2023) Romero-Avila, Diego; Omay, TolgaThis article examines the hypothesis of deterministic emissions convergence for a panel of the BRICS and Indonesia to advanced countries' emissions levels as well as to Sweden (which is a country that has clearly gone through decoupling) using a novel dataset with ten series of annual estimates of anthropogenic emissions comprising aerosols, aerosol precursor and reactive compounds, and carbon dioxide from 1820 to 2018. For that purpose, we employ four novel panel unit root tests allowing for several forms of time-dependent and state-dependent nonlinearity. The evidence supports deterministic convergence following a linear process for carbon dioxide, whereas the adjustment is asymmetric and nonlinear for carbon monoxide. Methane and nitrogen oxides exhibit logistic smooth transition converging dynamics. In contrast, black carbon, ammonia, nitrous oxide, non-methane volatile organic compounds, organic carbon, and sulfur dioxide emissions diverge. These results have implications for the abatement of greenhouse gases emissions at the global level, given the high share of emissions of the BRICS.Article Citation - WoS: 159Citation - Scopus: 164Economic Policy Uncertainty, Energy Consumption and Carbon Emissions in G7 Countries: Evidence From a Panel Granger Causality Analysis(Springer Heidelberg, 2020) Pirgaip, Burak; Dincergok, BurcuWe investigate the causal relationship between economic policy uncertainty (EPU) and energy consumption and carbon (CO2) emissions in G7 countries. We employ a bootstrap panel Granger causality test developed by Konya (Econ Model 23:978-992, 2006), using a yearly data set spanning from 1998 to 2018. Our test results provide significant support for a unidirectional causality running from EPU to energy consumption in Japan; from EPU to CO2 emissions in the USA and Germany; and from EPU to both energy consumption and CO2 emissions in Canada. In Italy, causality runs from CO2 emissions to EPU, but a bidirectional causality between EPU and energy consumption exists as well. We also explore a unidirectional causality that runs from energy consumption to CO2 in the USA. Based on the overall findings, we draw important implications for policymakers and we strongly recommend for G7 countries to take into account possible negative effects of EPU on energy conservation policies, which should be embarked upon to reduce energy consumption and CO2 emissions, as committed in their recent climate mandate.Article Citation - WoS: 3Citation - Scopus: 6Experimental Analysis of the Behavior of Composite Column-Reinforced Concrete Beam Joints(Springer Heidelberg, 2021) Tunc, Gokhan; Dakhil, Abdulrrahman; Mertol, Halit CenanThis study assesses the seismic performance of steel-reinforced concrete (SRC) composite columns connected to reinforced concrete (RC) beam joints, and their ability to dissipate seismic energy through inelastic deformations. In this article, experimental aspects regarding the seismic performance of high-ductility and low-ductility steel-concrete composite frame were investigated. The principle design parameter in this study was ductility, which is considered a conceptual framework in Efficiency-Based Seismic Engineering. Thus, attention was focused on assuring various ductility ranges of joints obtained through a detailed study of the Turkish Earthquake Code (TEC 18) [Ministry of Public Works and Housing.: Turkiye Bina Deprem Yonetmeligi (Turkey's Earthquake Code for Buildings). Official Gazette (2018) (in Turkish).]. After identifying deficiencies and the energy dissipation capacity in the newly proposed joints, two half-scaled frames with specific ductility-related designs were constructed, instrumented, tested, and analyzed. The specimens were tested under displacement-controlled lateral cyclic loading that incorporated constant axial loading to create cyclic tension and compression facets across the joint areas. The test results proved that the SRC column-RC beam frames employing an extra column reinforcement ratio exhibit slightly better seismic performance. Due to the presence of structural steel, the shear failure of the joint was effectively prevented, even after the formation of the plastic hinge on the interface of the beam. During the testing, the column rebars, to some extent, made a minor contribution to the joint strength of the specimen compared to the structural steel that absorbed almost all of the load applied to the frame.Article Citation - WoS: 9Citation - Scopus: 10Determination of the Relationship Between Uniaxial and Triaxial Swelling Equations for Clay Bearing Rocks(Springer Heidelberg, 2013) Bilir, M. Erdinc; Sari, Y. Dursun; Ozarslan, Ahmet; Genis, Melih; Sel, IbrahimDesign in swelling mediums is mostly based on uniaxial data since the standards proposed by the International Society for Rock Mechanics Commission on Swelling Rocks for uniaxial tests are in the form of recommendations, triaxial sets are not highly available; and there is no standard developed for triaxial tests. The main purpose of this study is to define the relationship between the uniaxial and the triaxial swelling equations and to predict the triaxial values using the uniaxial data. The other purpose of the study is to contribute to the development of the standards and to expand the data available in the literature about triaxial swelling behavior. Numerous uniaxial and triaxial swelling tests were performed on the samples from seven different locations, in Turkey, in a state of the art swelling laboratory. As a result of the determination of the triaxial swelling behavior of these samples, the relationships between the uniaxial and the triaxial swelling data for the individual samples as well as the whole set of samples are expressed by the equations derived from the statistical analyses.Article Citation - WoS: 12Citation - Scopus: 11Integrated Approach for Determining Spatio-Temporal Variations in the Hydrodynamic Factors as a Contributing Parameter in Landslide Susceptibility Assessments(Springer Heidelberg, 2019) Canoglu, Mustafa Can; Aksoy, Husnu; Ercanoglu, MuratAlthough general approaches to the effect of water on the mechanisms causing landslides have been adopted, the work presented in this paper was carried out to quantify the landslide susceptibility variation in space and time, integrating the soil moisture distribution and routing (SMDR) model and landslide susceptibility concept. The approach proposed in the present study reflects the temporal effects of the saturation degree index (SDI) on landslide susceptibility as a new index to understand the effect of soil saturation. The topographic wetness index (TWI) is a conventional parameter that represents the relative wetness on landsliding. The new proposed landslide susceptibility approach is used in the study area to understand the effect of soil saturation and the emergence of the Dereba landslide in the study area. The comparative results of landslide susceptibility maps obtained from the new approach utilizing the proposed SDI and conventional TWI are remarkable. Accordingly, a new substantial method is proposed using the attainable monthly mean meteorological data to generate monthly landslide susceptibility maps. The results obtained for the Dereba landslide using the proposed method are validated with the other landslide that has occurred in the same watershed. The results revealed that the approach proposed in this study was compatible with the landslide mechanism in the study area and may help to express the water effect in landslide susceptibility analyses.Article Citation - WoS: 7Citation - Scopus: 7Repetition or Alternation of Context Influences Sequential Congruency Effect Depending on the Presence of Contingency(Springer Heidelberg, 2017) Atalay, Nart Bedin; Inan, Asli BaharThe sequential congruency effect (SCE) is defined as the decrease in the congruency effect following incongruent trials compared to congruent trials. The effect of context repetition on the SCE was investigated in four experiments. In all the experiments, dynamic visual white noise was used as the contextual feature, and the number of congruent and incongruent trials was equal. In Experiments 1 and 2, by using eight-value Flanker and Stroop tasks, and excluding stimulus- and response-feature repetitions from the analysis, a SCE was observed in both context repetition and alternation conditions. In Experiment 3, using a two-value Flanker task, all trials consisted of stimulus- and response-feature repetitions, and a SCE was only observed in the context repetition condition. In Experiment 4, we used a four-value Flanker task, which enabled half of the trials to be partial/complete repetitions and the other half to be complete alternations. A SCE was observed in both context repetition and alternation conditions irrespective of the stimulus- and response-feature repetitions. This pattern of results suggested that the effects of context repetition on the SCE are subject to a number of factors including stimulus- and response-feature repetitions and contingency biases. When contingency information exists, the presence of stimulus- and response-feature repetitions was no longer effective in yielding effects of context repetition on the SCE. These findings suggest that the usage of information registered in episodic event representations including stimulus-, response- and contextual-features, control parameters and contingency biases results from interactions of a complex pattern of mechanisms, yet to be further explored.Article Citation - WoS: 6Citation - Scopus: 6Consistency of Spatiotemporal Variability of Modis and Era5-Land Surface Warming Trends Over Complex Topography(Springer Heidelberg, 2023) Yilmaz, MericIn this study, the trend of widely used MODIS MxD11 and MxD21 Land Surface Temperature (LST) and ERA5-Land Skin Temperature (SKT) and 2 m air temperature products were validated using 2 m air temperature trends obtained by ground observations from 266 stations in 2000-2021 over Turkey, known to have complex topography. The results show that colder regions have substantially higher temporal temperature variability than warmer ones. MxD21 and MxD11 products are 4.4 & DEG;C and 2.9 & DEG;C warmer than ERA5-Land products, respectively, while ERA5-Land products (SKT and 2 m) have nearly similar averages (12.5 & DEG;C). The consistency between MODIS and ERA5-Land data is significantly lower over areas with more complex topography and irrigation activities, despite the fact that the products show a high linear relationship over the study area. While February trends are consistently much higher than other months (2.2 and 1.4 & DEG;C/decade for MODIS and ERA5-Land, respectively), overall MODIS skin temperature products (0.7 & DEG;C/decade) generally exhibit smaller trends than ERA5-Land skin and air temperature trends (0.94 & DEG;C/decade). The results suggested that MODIS and ERA5-Land trends, which are highly consistent with observations, might replace observations in the absence of long-term station-based records.Article Citation - WoS: 29Citation - Scopus: 37A Guide for Validation of Fe-Simulations in Bulk Metal Forming(Springer Heidelberg, 2005) Tekkaya, AE; Manufacturing EngineeringNumerical analysis of metal forming processes is an everyday practice in industry. Forming loads, material flow, forming defects such as underfills, laps, and even cracks, stresses in dies and punches, as well as product properties like new hardness distribution, dimensional accuracies, and residual stresses are predicted by numerical analysis and used for technology generation. Most of the numerical analysis is done by the finite element method made available for engineers and technicians by numerous powerful commercial software packages. These software packages act as black-boxes and usually hide the complicated numerical procedures and even their crucial parameters from the applier. Therefore, the question arises during industrial applications: how accurate is the simulation, and how can the results be assessed? The aim of this paper is to provide a guideline to assess the results of metal forming simulations. Although some ideas are valid for any metal forming process, bulk forming is the primary concern. The paper will address firstly the possible sources of error in a finite element analysis of bulk forming processes. Then, some useful elementary knowledge will be summarized. Various levels of validation such as result and ability validation and assessment will be discussed. Finally, interpretation of results will be treated. In this content also some suggestions will be given.
