The city of Van is located to the Eastern Region of Turkey and has experienced two large earthquakes recently. Van earthquakes have caused big damages and demolitions in the city center, districts and in villages. As ...The city of Van is located to the Eastern Region of Turkey and has experienced two large earthquakes recently. Van earthquakes have caused big damages and demolitions in the city center, districts and in villages. As a result of precautions works have been realized to remove its effects shortly. However, it can be seen that the either urban or rural areas of the city carry the earthquake’s traces. Damages that the eartquake left on the buildings formed the most apparent and standing ones of the traces. Mud-brick buildings are the primary of those damaged buildings both in the centre of Van and in villages. Especially roofs’ collapsing and then walls’ demolition for mud-brick houses which were abandoned, and therefore were not maintained properly for a long time, are quite familiar situations after the earthquake. However, inhabited and maintained houses have been survived sturdily by contrast of other houses with modern materials and they helpt life to continue after the earthquake. In this study, mud-brick houses which were survived after earthquakes in Van and in the villages will be discussed. Reasons for demolition of those demolished and the qualities of those surviving ones will be scrutinized. It is going to be discussed how the mud-brick material which is distinguishing and struggling to gain it deserves as an ecological material today to resist against natural disasters sturdily when it is applied in decent way in scope with examples in the city of Van. Purpose of this study is to document right and wrong usage of the mud-brick materials with examples.展开更多
The early collapse of habitats in the spontaneous neighborhoods of the South-East of N’Djamena city pushed us to carry out investigations on the soil characteristics of the Ambatta 1 (Z1), Ambatta 2 (Z2), and Sigu...The early collapse of habitats in the spontaneous neighborhoods of the South-East of N’Djamena city pushed us to carry out investigations on the soil characteristics of the Ambatta 1 (Z1), Ambatta 2 (Z2), and Siguété (Z3) neighborhoods in this city. XRF (X-Ray Fluorescence), XRD (X-Ray Diffraction), FTIR (Fourier Transform InfraRed), SEM (Scanning Electron Microscopy), and ATG/DTA (Thermogravimetry Analysis/Differential Thermal Analysis) were conducted for microstructural and thermal identification. The geochemistry of the three soils studied revealed the presence of SiO2 (49.03% - 73.80%), Al2O3 (08.35% - 17.34%), and Fe2O3 (03.79% - 10.90%) as major elements. The alkalines and alkaline earth elements include potassium K2O (02.57% - 03.07%), magnesium MgO (0.47% - 01.21%), titanium TiO2 (0.81% - 01.41%), sodium Na2O (01.01% - 01.13%) and calcium CaO (01.28% - 03.28%). The fire loss of 09.90% on average remains low. XRD revealed the presence of quartz (~64.28%), feldspar (~07.14%), which are non-clay minerals, and clay minerals like kaolinite (~14.85%), illite (~07.14%) and some traces of smectite and amphibite on all three sites. These oxides were confirmed by FTIR analysis through peaks illustrating the vibrational movements specific to these oxides. SEM shows particles in the increasingly shaped, rounded, shiny sand grains. This is the presence of quartz. These quartz micro textures of abrasive surfaces and topography with conchoidal fractures predict promising mechanical results. Smectite appears in wavy clusters, kaolinite in the form of shiny crystals, and illite materializes by the irregularity of the crystalline shape. These constituents are represented by the presence of their oxides specified by geochemistry. Thermally, the three samples overall retain more than 94% of their constituent on average for a temperature range reaching 950˚C, which predestines them for specific applications. Thus, this study aims to stabilize constructions using local materials after having mastered their constituents.展开更多
The drilling process in orthopedic surgery can sometimes lead to an undesired increase in temperature,which can cause serious damage to bones and soft tissues.This overheating is typically identified as a temperature ...The drilling process in orthopedic surgery can sometimes lead to an undesired increase in temperature,which can cause serious damage to bones and soft tissues.This overheating is typically identified as a temperature above 47℃,known as the critical limit,and can result in the condition known as osteonecrosis.This study aims to develop a new control system,using a proportional-integral-derivative(PID)controller,to prevent overheating and the resulting osteonecrosis.The bone temperature is constantly measured using a thermocouple and,when it reaches the critical temperature of 47℃,the cooling device is activated by the PID-controlled system.This new control system makes the drill machine with cooling device more user-friendly and allows surgeons to set a desired temperature level manually.展开更多
Cross-shore sediment transport rate exposed to waves is very important for coastal morphology, the design of marine structures such as seawalls, jetties, breakwaters etc, and the prevention of coastal erosion and accr...Cross-shore sediment transport rate exposed to waves is very important for coastal morphology, the design of marine structures such as seawalls, jetties, breakwaters etc, and the prevention of coastal erosion and accretion due to onoff shore sediment transportation. In the present study, the experiments on cross-shore sediment transport are carried out in a laboratory wave channel with initial beach slopes of 1/8, 1/10 and 1/15. By using the regular waves with different deep-water wave steepnesses generated by a pedal-type wave generator, the geometrical characteristics of beach profiles under storm conditions and the parameters affecting on-off shore sediment transport are investigated for the beach materials with medium diameters of d50=0.25, 0.32, 0.45, 0.62 and 0.80 mm. The offshore bar geometric characteristics are the horizontal distances from the shoreline to the bar beginning (Xb), crest (Xt), and ending (Xs) points, the depth from the bar crest to the still water level (ht), and the bar volume (Vbar). The experimental results have indicated that when the deep-water steepness (Ha/L0) increased, the net movement to seaside increased. With the increasing wave steepness, the bars moved to widen herewith the vertical distances from still water level to the bar beginning (Xb), crest (Xt) and ending (Xs) points and the horizontal distances from the coast line to the bar beginning, crest and ending points increased. It was also shown from experimental results that the horizontal distances from the bar beginning and ending points to the coast line increased with the decrease of the beach slope. The experimental results obtained from this study are compared with previous experimental work and found to be of the same magnitude as the experimental measurements and followed the expected basic trend.展开更多
The attenuation of seismic waves reflects the elastic nature of the media within which the waves propagate.In this study,we calculate the Coda-Q(Qc),frequency dependence(η),Vp/Vs and Poisson's(υ)ratios by using ...The attenuation of seismic waves reflects the elastic nature of the media within which the waves propagate.In this study,we calculate the Coda-Q(Qc),frequency dependence(η),Vp/Vs and Poisson's(υ)ratios by using 2621 vertical component seismograms generated by 987 earthquakes recorded by 13 seismic stations in Eastern Anatolia,and creat a 2-D seismic tomographic Qc model for the region.The obtained model provides significant information for exploring the boundaries of adjacent tectonic units within the upper crust and interpreting their dynamic characteristics.The 2-D Qc model and the other parameters are consistent with the seismotectonic features of Eastern Anatolia.Highly heterogeneous Qc values are observed in the study area dividing it into north-south directed bands of low and high attenuation.The highestηvalues were obtained beneath the northwestern and eastern parts of the study region.Clear,high and lowυvalues are obtained in the western and eastern parts of the study area,respectively.The spatial variations in the measured parameters are consistent with many geophysical observations including low Pn velocities,efficient Sn blockage,high heat flow,and widespread volcanism.Different upper crustal thicknesses and inhomogeneous stress distribution along the East and North Anatolian Fault Zones may also contribute to the observed heterogeneities.展开更多
Increasing global energy consumption has become an urgent problem as natural energy sources such as oil,gas,and uranium are rapidly running out.Research into renewable energy sources such as solar energy is being purs...Increasing global energy consumption has become an urgent problem as natural energy sources such as oil,gas,and uranium are rapidly running out.Research into renewable energy sources such as solar energy is being pursued to counter this.Solar energy is one of the most promising renewable energy sources,as it has the potential to meet the world’s energy needs indefinitely.This study aims to develop and evaluate artificial intelligence(AI)models for predicting hourly global irradiation.The hyperparameters were optimized using the Broyden-FletcherGoldfarb-Shanno(BFGS)quasi-Newton training algorithm and STATISTICA software.Data from two stations in Algeria with different climatic zones were used to develop the model.Various error measurements were used to determine the accuracy of the prediction models,including the correlation coefficient,the mean absolute error,and the root mean square error(RMSE).The optimal support vector machine(SVM)model showed exceptional efficiency during the training phase,with a high correlation coefficient(R=0.99)and a low mean absolute error(MAE=26.5741 Wh/m^(2)),as well as an RMSE of 38.7045 Wh/m^(2) across all phases.Overall,this study highlights the importance of accurate prediction models in the renewable energy,which can contribute to better energy management and planning.展开更多
This paper investigates the effects of tool holder materials on chatter vibration in turning operations.The study uses a complex dynamic turning model with two degrees of freedom for the orthogonal cutting system.Tool...This paper investigates the effects of tool holder materials on chatter vibration in turning operations.The study uses a complex dynamic turning model with two degrees of freedom for the orthogonal cutting system.Tool holders made from different materials,including Al 5083,Al 6082,Al 7012,and a standard 4140 material,were subjected to chatter vibration to investigate their process damping capabilities.The study found that the standard tool holder 4140 allows for higher stable depths of cut and produces similar process damping values compared to the other tool holders.Finite element analyses(FEA)were performed to verify the experimental results,and the modal and FEA analyses produced very similar results.The study concludes that future research should investigate the effects of tool holders made from high alloy steel alloys on process damping.Overall,this paper provides important insights into the effects of tool hold-er materials on chatter vibration and process damping in turning operations,which can help in the design of more effi-cient and effective cutting systems.展开更多
In this study,the reason for erosion-corrosion of drinking or mains water in the faucet was investigated by computational fluid dynamics.Pipes used in homes,the service sector,and industry are responsible for transpor...In this study,the reason for erosion-corrosion of drinking or mains water in the faucet was investigated by computational fluid dynamics.Pipes used in homes,the service sector,and industry are responsible for transporting different types of fluids from one place to another.Considering the faucet design,the SolidWorks program was used for 3D studies.In-faucet flow analyses were performed using Ansys Fluent,a computational fluid dynamics program based on the finite volume method.In the analyses,lime particles were chosen.At the end of the analysis,the amount of erosion in the faucet was obtained.展开更多
In 2018,1.76 million people worldwide died of lung cancer.Most of these deaths are due to late diagnosis,and early-stage diagnosis significantly increases the likelihood of a successful treatment for lung cancer.Machi...In 2018,1.76 million people worldwide died of lung cancer.Most of these deaths are due to late diagnosis,and early-stage diagnosis significantly increases the likelihood of a successful treatment for lung cancer.Machine learning is a branch of artificial intelligence that allows computers to quickly identify patterns within complex and large datasets by learning from existing data.Machine-learning techniques have been improving rapidly and are increasingly used by medical professionals for the successful classification and diagnosis of early-stage disease.They are widely used in cancer diagnosis.In particular,machine learning has been used in the diagnosis of lung cancer due to the benefits it offers doctors and patients.In this context,we performed a study on machine-learning techniques to increase the classification accuracy of lung cancer with 32×56 sized numerical data from the Machine Learning Repository web site of the University of California,Irvine.In this study,the precision of the classification model was increased by the effective employment of pre-processing methods instead of direct use of classification algorithms.Nine datasets were derived with pre-processing methods and six machine-learning classification methods were used to achieve this improvement.The study results suggest that the accuracy of the k-nearest neighbors algorithm is superior to random forest,naïve Bayes,logistic regression,decision tree,and support vector machines.The performance of pre-processing methods was assessed on the lung cancer dataset.The most successful preprocessing methods were Z-score(83%accuracy)for normalization methods,principal component analysis(87%accuracy)for dimensionality reduction methods,and information gain(71%accuracy)for feature selection methods.展开更多
Calcareous nannoplankton biostratigraphy has been performed on five sedimentary sections through the marine Akveren Formation from the Bartin region of northern Turkey, on the southern Black Sea coast. This new biostr...Calcareous nannoplankton biostratigraphy has been performed on five sedimentary sections through the marine Akveren Formation from the Bartin region of northern Turkey, on the southern Black Sea coast. This new biostratigraphy provides an age for the formation of the Early Campanian (nannofossil zone UC15aTp) to Early Selandian (nannofossil zone NPS), and highlights the presence of the Campanian/Maastrichtian, Cretaceous/Tertiary (K/T), and Danian/Selandian boundaries in this intermediate palaeolatitude location. Micula murus was identified below the K/T boundary, but Micula prinsii and Nephrolithus frequens were not, which implies that the K/T boundary interval is not complete in the study area. These dates are in agreement with previous micropaleontological studies.展开更多
In this study, effective atomic numbers(Zeff) of materials determined at different experimental conditions by measuring the elastic-to-inelastic γ-ray scattering ratios are compared to ZXCOM predictions. It also pres...In this study, effective atomic numbers(Zeff) of materials determined at different experimental conditions by measuring the elastic-to-inelastic γ-ray scattering ratios are compared to ZXCOM predictions. It also presents the experimental data obtained via the transmission technique The agreement and disagreement between ZXCOM and experimental values are investigated. The theoretical basics of determining Zeffby scattering mode are outlined. The study shows that choosing appropriate experimental conditions can provide a good compatibility between the experimental results and theoretical ZXCOM展开更多
In this research it is aimed to predict fabrics’air permeability properties by ANNs(artificial neural networks)before production with using inputs like some fabric parameters and finishing treatments.For this aim 27 ...In this research it is aimed to predict fabrics’air permeability properties by ANNs(artificial neural networks)before production with using inputs like some fabric parameters and finishing treatments.For this aim 27 various fabrics were weaved.After dyeing finishing treatments for antipilling were applied to fabrics in 3 concentrations.ANN models were established to predict fabrics’air permeability values with the selected 6 inputs such as weft yarn number,weft density,weaving pattern,fabric weight,fabric thickness and finishing treatment concentrations.The best results whose regression degree is R=0.99366,were obtained with two hidden layer networks with 5 neurons.展开更多
This article focuses on a technique for shallow mechanical improvement of soil which deals with the utilization of crushed granite mixed in a certain percentage with lateritic soils during road construction in Burkina...This article focuses on a technique for shallow mechanical improvement of soil which deals with the utilization of crushed granite mixed in a certain percentage with lateritic soils during road construction in Burkina Faso.Lithostab is the simplified name for litho-stabilization,a technique for improving laterite by adding crushed granite that increases the CBR(California bearing ratio)of that material for being used in road construction.Class 0/25 of crushed granite added to a laterite in our case gives good performance in terms of CBR.Indeed,the CBR index which was initially 48 at 98%of the OMP(optimum modified Proctor)goes to 88.And from 84 at 98%of the OMP,it goes to 128 for 30%of class 0/25 of crushed granite added.This means that class 0/25 of crushed granite provides better CBR index to that material when it is incorporated at 30%.So,lithostab is an easy to implement eco-friendly material for road construction because of the utilization of local materials.Then,it contributes to the protection of the environment in the sense that its production does not require a lot of energy and does not release large quantities of carbon dioxide into the atmosphere.展开更多
In this study, CoCrMo alloy was oxidized in plasma environment at the temperatures of 600 ℃ to 800 ℃ for 1 h to 5 h with 100% 02 gas and its tribological behavior was investigated. After the plasma oxidizing process...In this study, CoCrMo alloy was oxidized in plasma environment at the temperatures of 600 ℃ to 800 ℃ for 1 h to 5 h with 100% 02 gas and its tribological behavior was investigated. After the plasma oxidizing process, the compound and diffusion layers were formed on the surface. XRD results show that Cr203, a-Co and ε-Co phases diffracted from the modified layers after plasma oxidizing. The untreated and treated CoCrMo samples were subjected to wear tests both in dry and simulated body fluid conditions, and normal loads of 2 N and 10 N were used. For the sliding wear test, alumina balls were used as counter materials. It was observed that the wear resistance of CoCrMo alloy was increased after the plasma oxidizing process. The lowest wear rate was obtained from the samples that were oxidized at 800 ℃ for 5 h. It was detected that both wear environment and load have significant effects on the wear behavior of this alloy, and the wear resistance of oxidized CoCrMo alloy is higher when oxide-based counterface is used. The wear rates of both untreated and plasma oxidized samples increase under high loads.展开更多
The structural,morphological,optical,and nonlinear optical properties of a lead sulfde(PbS) thin film grown by chemical bath deposition(CBD) are investigated by X-ray difraction(XRD),scanning electron microscope(SEM),...The structural,morphological,optical,and nonlinear optical properties of a lead sulfde(PbS) thin film grown by chemical bath deposition(CBD) are investigated by X-ray difraction(XRD),scanning electron microscope(SEM),ultraviolet-visible(UV-Vis),and open aperture Z-scan experiments.The band gap energy of the PbS nanocrystalline film is 1.82 eV,higher than that of bulk PbS at 300 K.The nonlinear absorption properties of the film are investigated using the open aperture Z-scan technique at 1064 nm and pulse durations of 4 ns and 65 ps.Intensity-dependent switching of the film from nonlinear absorption to saturable absorption is observed.The nonlinear absorption coefficient increases monotonically with increasing pulse duration from 65 ps to 4 ns.展开更多
The structural, morphological, optical, and nonlinear optical properties of a lead sulfide (PbS) thin film grown by chemical bath deposition (CBD) are investigated by X-ray diffraction (XRD), scanning electron m...The structural, morphological, optical, and nonlinear optical properties of a lead sulfide (PbS) thin film grown by chemical bath deposition (CBD) are investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), ultraviolet-visible (UV-Vis), and open aperture Z-scan experiments. The band gap energy of the PbS nanocrystalline film is 1.82 eV~ higher than that of bulk PbS at 300 K. The nonlinear absorption properties of the film are investigated using the open aperture Z-scan technique at 1064 nm and pulse durations of 4 ns and 65 ps. Intensity-dependent switching of the film from nonlinear absorption to saturable absorption is observed. The nonlinear absorption coefficient increases monotonically with increasing pulse duration from 65 ps to 4 ns.展开更多
The current work aims to present abundant families of the exact solutions of Mikhailov-Novikov-Wang equation via three different techniques.The adopted methods are generalized Kudryashov method(GKM),exponential ration...The current work aims to present abundant families of the exact solutions of Mikhailov-Novikov-Wang equation via three different techniques.The adopted methods are generalized Kudryashov method(GKM),exponential rational function method(ERFM),and modified extended tanh-function method(METFM).Some plots of some presented new solutions are represented to exhibit wave characteristics.All results in this work are essential to understand the physical meaning and behavior of the investigated equation that sheds light on the importance of investigating various nonlinear wave phenomena in ocean engineering and physics.This equation provides new insights to understand the relationship between the integrability and water waves’phenomena.展开更多
文摘The city of Van is located to the Eastern Region of Turkey and has experienced two large earthquakes recently. Van earthquakes have caused big damages and demolitions in the city center, districts and in villages. As a result of precautions works have been realized to remove its effects shortly. However, it can be seen that the either urban or rural areas of the city carry the earthquake’s traces. Damages that the eartquake left on the buildings formed the most apparent and standing ones of the traces. Mud-brick buildings are the primary of those damaged buildings both in the centre of Van and in villages. Especially roofs’ collapsing and then walls’ demolition for mud-brick houses which were abandoned, and therefore were not maintained properly for a long time, are quite familiar situations after the earthquake. However, inhabited and maintained houses have been survived sturdily by contrast of other houses with modern materials and they helpt life to continue after the earthquake. In this study, mud-brick houses which were survived after earthquakes in Van and in the villages will be discussed. Reasons for demolition of those demolished and the qualities of those surviving ones will be scrutinized. It is going to be discussed how the mud-brick material which is distinguishing and struggling to gain it deserves as an ecological material today to resist against natural disasters sturdily when it is applied in decent way in scope with examples in the city of Van. Purpose of this study is to document right and wrong usage of the mud-brick materials with examples.
文摘The early collapse of habitats in the spontaneous neighborhoods of the South-East of N’Djamena city pushed us to carry out investigations on the soil characteristics of the Ambatta 1 (Z1), Ambatta 2 (Z2), and Siguété (Z3) neighborhoods in this city. XRF (X-Ray Fluorescence), XRD (X-Ray Diffraction), FTIR (Fourier Transform InfraRed), SEM (Scanning Electron Microscopy), and ATG/DTA (Thermogravimetry Analysis/Differential Thermal Analysis) were conducted for microstructural and thermal identification. The geochemistry of the three soils studied revealed the presence of SiO2 (49.03% - 73.80%), Al2O3 (08.35% - 17.34%), and Fe2O3 (03.79% - 10.90%) as major elements. The alkalines and alkaline earth elements include potassium K2O (02.57% - 03.07%), magnesium MgO (0.47% - 01.21%), titanium TiO2 (0.81% - 01.41%), sodium Na2O (01.01% - 01.13%) and calcium CaO (01.28% - 03.28%). The fire loss of 09.90% on average remains low. XRD revealed the presence of quartz (~64.28%), feldspar (~07.14%), which are non-clay minerals, and clay minerals like kaolinite (~14.85%), illite (~07.14%) and some traces of smectite and amphibite on all three sites. These oxides were confirmed by FTIR analysis through peaks illustrating the vibrational movements specific to these oxides. SEM shows particles in the increasingly shaped, rounded, shiny sand grains. This is the presence of quartz. These quartz micro textures of abrasive surfaces and topography with conchoidal fractures predict promising mechanical results. Smectite appears in wavy clusters, kaolinite in the form of shiny crystals, and illite materializes by the irregularity of the crystalline shape. These constituents are represented by the presence of their oxides specified by geochemistry. Thermally, the three samples overall retain more than 94% of their constituent on average for a temperature range reaching 950˚C, which predestines them for specific applications. Thus, this study aims to stabilize constructions using local materials after having mastered their constituents.
基金supported by the Department of Scientific Research Project Unit at Kocaeli University under the project number of 2012/44.
文摘The drilling process in orthopedic surgery can sometimes lead to an undesired increase in temperature,which can cause serious damage to bones and soft tissues.This overheating is typically identified as a temperature above 47℃,known as the critical limit,and can result in the condition known as osteonecrosis.This study aims to develop a new control system,using a proportional-integral-derivative(PID)controller,to prevent overheating and the resulting osteonecrosis.The bone temperature is constantly measured using a thermocouple and,when it reaches the critical temperature of 47℃,the cooling device is activated by the PID-controlled system.This new control system makes the drill machine with cooling device more user-friendly and allows surgeons to set a desired temperature level manually.
基金supported by ukurova University Research Fund under the Project No. CUMMF2004D5
文摘Cross-shore sediment transport rate exposed to waves is very important for coastal morphology, the design of marine structures such as seawalls, jetties, breakwaters etc, and the prevention of coastal erosion and accretion due to onoff shore sediment transportation. In the present study, the experiments on cross-shore sediment transport are carried out in a laboratory wave channel with initial beach slopes of 1/8, 1/10 and 1/15. By using the regular waves with different deep-water wave steepnesses generated by a pedal-type wave generator, the geometrical characteristics of beach profiles under storm conditions and the parameters affecting on-off shore sediment transport are investigated for the beach materials with medium diameters of d50=0.25, 0.32, 0.45, 0.62 and 0.80 mm. The offshore bar geometric characteristics are the horizontal distances from the shoreline to the bar beginning (Xb), crest (Xt), and ending (Xs) points, the depth from the bar crest to the still water level (ht), and the bar volume (Vbar). The experimental results have indicated that when the deep-water steepness (Ha/L0) increased, the net movement to seaside increased. With the increasing wave steepness, the bars moved to widen herewith the vertical distances from still water level to the bar beginning (Xb), crest (Xt) and ending (Xs) points and the horizontal distances from the coast line to the bar beginning, crest and ending points increased. It was also shown from experimental results that the horizontal distances from the bar beginning and ending points to the coast line increased with the decrease of the beach slope. The experimental results obtained from this study are compared with previous experimental work and found to be of the same magnitude as the experimental measurements and followed the expected basic trend.
文摘The attenuation of seismic waves reflects the elastic nature of the media within which the waves propagate.In this study,we calculate the Coda-Q(Qc),frequency dependence(η),Vp/Vs and Poisson's(υ)ratios by using 2621 vertical component seismograms generated by 987 earthquakes recorded by 13 seismic stations in Eastern Anatolia,and creat a 2-D seismic tomographic Qc model for the region.The obtained model provides significant information for exploring the boundaries of adjacent tectonic units within the upper crust and interpreting their dynamic characteristics.The 2-D Qc model and the other parameters are consistent with the seismotectonic features of Eastern Anatolia.Highly heterogeneous Qc values are observed in the study area dividing it into north-south directed bands of low and high attenuation.The highestηvalues were obtained beneath the northwestern and eastern parts of the study region.Clear,high and lowυvalues are obtained in the western and eastern parts of the study area,respectively.The spatial variations in the measured parameters are consistent with many geophysical observations including low Pn velocities,efficient Sn blockage,high heat flow,and widespread volcanism.Different upper crustal thicknesses and inhomogeneous stress distribution along the East and North Anatolian Fault Zones may also contribute to the observed heterogeneities.
文摘Increasing global energy consumption has become an urgent problem as natural energy sources such as oil,gas,and uranium are rapidly running out.Research into renewable energy sources such as solar energy is being pursued to counter this.Solar energy is one of the most promising renewable energy sources,as it has the potential to meet the world’s energy needs indefinitely.This study aims to develop and evaluate artificial intelligence(AI)models for predicting hourly global irradiation.The hyperparameters were optimized using the Broyden-FletcherGoldfarb-Shanno(BFGS)quasi-Newton training algorithm and STATISTICA software.Data from two stations in Algeria with different climatic zones were used to develop the model.Various error measurements were used to determine the accuracy of the prediction models,including the correlation coefficient,the mean absolute error,and the root mean square error(RMSE).The optimal support vector machine(SVM)model showed exceptional efficiency during the training phase,with a high correlation coefficient(R=0.99)and a low mean absolute error(MAE=26.5741 Wh/m^(2)),as well as an RMSE of 38.7045 Wh/m^(2) across all phases.Overall,this study highlights the importance of accurate prediction models in the renewable energy,which can contribute to better energy management and planning.
基金This study was supported by the Scientific Research Coordination Unit of Pamukkale University under the project number 2011BSP020.
文摘This paper investigates the effects of tool holder materials on chatter vibration in turning operations.The study uses a complex dynamic turning model with two degrees of freedom for the orthogonal cutting system.Tool holders made from different materials,including Al 5083,Al 6082,Al 7012,and a standard 4140 material,were subjected to chatter vibration to investigate their process damping capabilities.The study found that the standard tool holder 4140 allows for higher stable depths of cut and produces similar process damping values compared to the other tool holders.Finite element analyses(FEA)were performed to verify the experimental results,and the modal and FEA analyses produced very similar results.The study concludes that future research should investigate the effects of tool holders made from high alloy steel alloys on process damping.Overall,this paper provides important insights into the effects of tool hold-er materials on chatter vibration and process damping in turning operations,which can help in the design of more effi-cient and effective cutting systems.
文摘In this study,the reason for erosion-corrosion of drinking or mains water in the faucet was investigated by computational fluid dynamics.Pipes used in homes,the service sector,and industry are responsible for transporting different types of fluids from one place to another.Considering the faucet design,the SolidWorks program was used for 3D studies.In-faucet flow analyses were performed using Ansys Fluent,a computational fluid dynamics program based on the finite volume method.In the analyses,lime particles were chosen.At the end of the analysis,the amount of erosion in the faucet was obtained.
基金This study was funded by TÜB˙ITAK(The Scientific and Technological Research Council of Turkey)(https://www.tubitak.gov.tr/tr/burslar/lisans/burs-programlari/icerik2209-a-universite-ogrencileri-arastirma-projeleri-destekleme-programi).The grant name and number are“Machine Learning-Based Lung Cancer Detection”and“2209/A-2018”,respectively。
文摘In 2018,1.76 million people worldwide died of lung cancer.Most of these deaths are due to late diagnosis,and early-stage diagnosis significantly increases the likelihood of a successful treatment for lung cancer.Machine learning is a branch of artificial intelligence that allows computers to quickly identify patterns within complex and large datasets by learning from existing data.Machine-learning techniques have been improving rapidly and are increasingly used by medical professionals for the successful classification and diagnosis of early-stage disease.They are widely used in cancer diagnosis.In particular,machine learning has been used in the diagnosis of lung cancer due to the benefits it offers doctors and patients.In this context,we performed a study on machine-learning techniques to increase the classification accuracy of lung cancer with 32×56 sized numerical data from the Machine Learning Repository web site of the University of California,Irvine.In this study,the precision of the classification model was increased by the effective employment of pre-processing methods instead of direct use of classification algorithms.Nine datasets were derived with pre-processing methods and six machine-learning classification methods were used to achieve this improvement.The study results suggest that the accuracy of the k-nearest neighbors algorithm is superior to random forest,naïve Bayes,logistic regression,decision tree,and support vector machines.The performance of pre-processing methods was assessed on the lung cancer dataset.The most successful preprocessing methods were Z-score(83%accuracy)for normalization methods,principal component analysis(87%accuracy)for dimensionality reduction methods,and information gain(71%accuracy)for feature selection methods.
基金The Erciyes University provided financial support for this study (Project No.FBT-06-24)
文摘Calcareous nannoplankton biostratigraphy has been performed on five sedimentary sections through the marine Akveren Formation from the Bartin region of northern Turkey, on the southern Black Sea coast. This new biostratigraphy provides an age for the formation of the Early Campanian (nannofossil zone UC15aTp) to Early Selandian (nannofossil zone NPS), and highlights the presence of the Campanian/Maastrichtian, Cretaceous/Tertiary (K/T), and Danian/Selandian boundaries in this intermediate palaeolatitude location. Micula murus was identified below the K/T boundary, but Micula prinsii and Nephrolithus frequens were not, which implies that the K/T boundary interval is not complete in the study area. These dates are in agreement with previous micropaleontological studies.
基金supported by the Yildiz Technical University(No.2015-01-01-KAP06)the Scientific and Technological Research Council of Turkey(TUBITAK)(No.2015-115F311)
文摘In this study, effective atomic numbers(Zeff) of materials determined at different experimental conditions by measuring the elastic-to-inelastic γ-ray scattering ratios are compared to ZXCOM predictions. It also presents the experimental data obtained via the transmission technique The agreement and disagreement between ZXCOM and experimental values are investigated. The theoretical basics of determining Zeffby scattering mode are outlined. The study shows that choosing appropriate experimental conditions can provide a good compatibility between the experimental results and theoretical ZXCOM
文摘In this research it is aimed to predict fabrics’air permeability properties by ANNs(artificial neural networks)before production with using inputs like some fabric parameters and finishing treatments.For this aim 27 various fabrics were weaved.After dyeing finishing treatments for antipilling were applied to fabrics in 3 concentrations.ANN models were established to predict fabrics’air permeability values with the selected 6 inputs such as weft yarn number,weft density,weaving pattern,fabric weight,fabric thickness and finishing treatment concentrations.The best results whose regression degree is R=0.99366,were obtained with two hidden layer networks with 5 neurons.
文摘This article focuses on a technique for shallow mechanical improvement of soil which deals with the utilization of crushed granite mixed in a certain percentage with lateritic soils during road construction in Burkina Faso.Lithostab is the simplified name for litho-stabilization,a technique for improving laterite by adding crushed granite that increases the CBR(California bearing ratio)of that material for being used in road construction.Class 0/25 of crushed granite added to a laterite in our case gives good performance in terms of CBR.Indeed,the CBR index which was initially 48 at 98%of the OMP(optimum modified Proctor)goes to 88.And from 84 at 98%of the OMP,it goes to 128 for 30%of class 0/25 of crushed granite added.This means that class 0/25 of crushed granite provides better CBR index to that material when it is incorporated at 30%.So,lithostab is an easy to implement eco-friendly material for road construction because of the utilization of local materials.Then,it contributes to the protection of the environment in the sense that its production does not require a lot of energy and does not release large quantities of carbon dioxide into the atmosphere.
文摘In this study, CoCrMo alloy was oxidized in plasma environment at the temperatures of 600 ℃ to 800 ℃ for 1 h to 5 h with 100% 02 gas and its tribological behavior was investigated. After the plasma oxidizing process, the compound and diffusion layers were formed on the surface. XRD results show that Cr203, a-Co and ε-Co phases diffracted from the modified layers after plasma oxidizing. The untreated and treated CoCrMo samples were subjected to wear tests both in dry and simulated body fluid conditions, and normal loads of 2 N and 10 N were used. For the sliding wear test, alumina balls were used as counter materials. It was observed that the wear resistance of CoCrMo alloy was increased after the plasma oxidizing process. The lowest wear rate was obtained from the samples that were oxidized at 800 ℃ for 5 h. It was detected that both wear environment and load have significant effects on the wear behavior of this alloy, and the wear resistance of oxidized CoCrMo alloy is higher when oxide-based counterface is used. The wear rates of both untreated and plasma oxidized samples increase under high loads.
文摘The structural,morphological,optical,and nonlinear optical properties of a lead sulfde(PbS) thin film grown by chemical bath deposition(CBD) are investigated by X-ray difraction(XRD),scanning electron microscope(SEM),ultraviolet-visible(UV-Vis),and open aperture Z-scan experiments.The band gap energy of the PbS nanocrystalline film is 1.82 eV,higher than that of bulk PbS at 300 K.The nonlinear absorption properties of the film are investigated using the open aperture Z-scan technique at 1064 nm and pulse durations of 4 ns and 65 ps.Intensity-dependent switching of the film from nonlinear absorption to saturable absorption is observed.The nonlinear absorption coefficient increases monotonically with increasing pulse duration from 65 ps to 4 ns.
文摘The structural, morphological, optical, and nonlinear optical properties of a lead sulfide (PbS) thin film grown by chemical bath deposition (CBD) are investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), ultraviolet-visible (UV-Vis), and open aperture Z-scan experiments. The band gap energy of the PbS nanocrystalline film is 1.82 eV~ higher than that of bulk PbS at 300 K. The nonlinear absorption properties of the film are investigated using the open aperture Z-scan technique at 1064 nm and pulse durations of 4 ns and 65 ps. Intensity-dependent switching of the film from nonlinear absorption to saturable absorption is observed. The nonlinear absorption coefficient increases monotonically with increasing pulse duration from 65 ps to 4 ns.
文摘The current work aims to present abundant families of the exact solutions of Mikhailov-Novikov-Wang equation via three different techniques.The adopted methods are generalized Kudryashov method(GKM),exponential rational function method(ERFM),and modified extended tanh-function method(METFM).Some plots of some presented new solutions are represented to exhibit wave characteristics.All results in this work are essential to understand the physical meaning and behavior of the investigated equation that sheds light on the importance of investigating various nonlinear wave phenomena in ocean engineering and physics.This equation provides new insights to understand the relationship between the integrability and water waves’phenomena.