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The mechanical status of the cervix is a key physiological element during pregnancy. By considering a successful induction when the active phase of labor is achieved, mapping the mechanical properties of the cervix could have predictive potential for the management of induction protocols. In this sense, we performed a preliminary assessment of the diagnostic value of using shear wave elastography before labor induction in 54 women, considering the pregnancy outcome and Cesarean indications. Three anatomical cervix regions and standard methods, such as cervical length and Bishop score, were compared. To study the discriminatory power of each diagnostic method, a receiver operating characteristic curve was generated. Differences were observed using the external os region and cervical length in the failure to enter the active phase group compared to the vaginal delivery group (p < 0.05). The area under the ROC curve resulted in 68.9%, 65.2% and 67.2% for external os, internal os and cervix box using elastography, respectively, compared to 69.5% for cervical length and 62.2% for Bishop score. External os elastography values have shown promise in predicting induction success. This a priori information could be used to prepare a study with a larger sample size, which would reduce the effect of any bias selection and increase the predictive power of elastography compared to other classical techniques., Ministerio de Educacion, Cultura y Deporte grant DPI2017-83859-R DPI2014-51870-R UNGR15-CE-3664 EQC2018-004508-P, Spanish Government DTS15/00093 PI16/00339, Instituto de Salud Carlos III, Spanish Government, European Commission PID2020-115372RB-I00 PYC20 RE 072 UGR, Instituto de Salud Carlos III y Fondos Feder, Junta de Andalucia PI-0107-2017 PIN-0030-2017 IE2017-5537 B-TEP-026-UGR18 P18-RT-1653, MCIN/AEI (European Social Fund "Investing in your future") PRE2018-086085, European Commission P18-RT-1653 SOMM17/6109/UGR

WOS: 000467349000044, In this study, single lap joints were formed by adding nano-Al2O3, nano-TiO2 and nano-Al2O3 powders in various proportions to the epoxy adhesive and using the additive-free epoxy adhesive; and also the mechanical properties of the connections were experimentally investigated at 20, 25, 30, 50 and 70 mm overlap lengths under shear load. In the experimental work, DP460 epoxy adhesive was used as adhesive and AISI 304 stainless steel plate as adherent material. When the results obtained from the experiments were examined, it was revealed that the average damage load in connection with the use of nanoparticle-added adhesives increased considerably in general. As a result of the experiments, the most effective nanoparticle in increasing the failure strength of the adhesive joints with nano-Al2O3 particles and the maximum failure strength increase rate was 20 mm in overlap length and 97% in 4 wt% nano-Al2O3 reinforced specimens. It was also found that the nanoparticle strain was an important parameter in the tensile strength of the adhesive joints. In addition, it has been found that the addition of nanoparticles into the adhesive increases the elongation of the joints. When the adhesion surfaces of the samples were examined as in the case of plain adhesives, damage was observed as adhesion separation while nanoparticle reinforcement was observed as a mixture of adhesion and cohesion., Batman University Scientific Research Projects (BAP) [BTUBAP-2016-PhD-2], We are grateful to Batman University Scientific Research Projects (BAP) Coordinator for providing financial support for the realization of our work (Project number: BTUBAP-2016-PhD-2).

Materials with fluid and matrix phases present different acoustic responses in each phase. While longitudinal waves propagate in both phases, shear waves do it only through the solid matrix. Longitudinal waves are mainly described by volumetric propagation and shear waves by deviatoric processes. In the case of nonlinear propagation cross effects occur between both components. This paper presents a new classical nonlinear model proposing a constitutive equation that separates volumetric and deviatoric effects. Four nonlinear constants of third order are defined. The formulation is compared to constitutive equations with Landau constants for weakly elasticity and both types of nonlinear constants related. Some reinterpretation of the Landau's constants arises in terms of parallel or cross nonlinear effects between volumetric and deviatoric components., Ministry of Education [Grant nos. DPI2014-51870-R, DPI2017-85359-R, and UNGR15-CE-3664], Ministry of Health [DTS15/00093 and PI16/00339], Junta de Andalucía [PIN-0030-2017 and PI0107-2017 projects], University of Granada [PP2017- PIP2019]

WOS: 000433239500015, The influence of alumina (Al2O3) nanoparticles addition upon low-velocity impact behaviors of carbon fiber (CF) reinforced laminated epoxy nanocomposites have been investigated. For this purpose, different amounts of Al2O3 nanoparticles ranging from 1 to 5 wt% were added to the epoxy resin in order to observe the effect of nanoparticle loadings. CF reinforced epoxy based laminated nanocomposites were produced using Vacuum Assisted Resin Infusion Method (VARIM). The low velocity impact (LVI) tests performed according to the ASTM-D-7136 standard under 2, 2.5 and 3 m/s impact velocities. After LVI testing, the damage formations within composites were examined by using scanning electron microscopy (SEM). The results of this study showed that addition of Al2O3 nanoparticles provided a significant improvement in impact damage resistance. The highest damage resistance and minimum energy absorption were observed for 2 wt% Al2O3 nanoparticles loadings. As a result, we can confidently claim that the addition of the Al2O3 nanoparticles in CF/epoxy composites has considerably affected the dynamic response of the nanocomposites. (C) 2018 Karabuk University. Publishing services by Elsevier B.V.

WOS: 000431972300004 Effective cooling of electronic components plays an important role in system design and efficiency. In this study, the effects of using the flow routing plate in cooling printed circuit boards have been investigated. For this purpose, effects of the flow routing plate on the laminar mixed convection heat transfer from protruded heat sources at the side walls of the horizontal channel, were investigated numerically. The air was used as cooling fluid, and protruded heat sources were equipped as rows into the rectangular channel with insulated walls. Numerical investigations were carried out for different plate inclination angles at different Reynolds and modified Grashof numbers. It is observed that the using of flow routing plate increases the heat transfer at different ratios by comparison to the case without plate and enhances the cooling conditions for all values of parameters in the analyses. The highest heat transfer enhancement occurred at values where Reynolds number (Re) was Re = 1000 and plate inclination angle (alpha) was alpha = 60 degrees. The results obtained during the numerical analyses are presented in detail in the form of graphics for the row averaged Nusselt number, heater temperatures, velocity vectors, and temperature contours.

WOS: 000418289300012 The determination of the cutting-parameter values that cause increases in vibration values is important to minimize the errors that can occur. Thus, the first aim of this study was to investigate the optimum cutting-parameter values and tool-path strategies in ball-end milling of the EN X40CrMoV5-1 tool steel with three coated cutters using the Taguchi method. The parameters taken into consideration are the cutting speed, feed rate, step over and tool-path strategies. The second aim of the study, a model for the tool acceleration as a function of the cutting parameters, was obtained using the response-surface methodology (RSM). As a result, the most effective parameter within the selected cutting parameters and cutting strategies for both inclined surfaces and different coatings was the step over. In terms of tool coatings, the most deteriorating coating for the tool acceleration on both inclined surfaces was the TiC coating. In addition, the response-surface methodology is employed to predict the tool-vibration values depending on the cutting parameters and tool-path strategy. The model generated gives highly accurate results.

WOS: 000423970000010, The study compares the microstructure of three commercial dental cobalt matrix alloys with related chemical composition declared by the manufacturer. Casts were produced with lost wax method, then melted and caged with centrifugal induction casting machine. The Co-Cr-Mo alloys were casted according to the manufacturers procedure. The samples chemical composition and phase composition. respectively. using WD-XRF (Wavelength Dispersive X-Ray Fluorescence) and XRD (X-ray Diffarction) methods were analysed. Casts microstructure by mean of LOM (Light Optical Microscopy). SEM (Scanning Electron Microscopy) and EDS (Energy Dispersive X-ray Spectroscopy) were investigated. Vickers hardness HV10 was measured. Quantitative microstructure evaluation was performed by means of computer image processing. The results of the chemical composition indicate the high stability of the chemical composition for alloy A. In case of alloys B and C. there was a significant difference in carbon content. Quantitative differences in image of microstructure between of castings A and B, C were noticed. The greater amount of precipitates was recorded for castings with higher carbon content. In all investigated castings, the presence of matrix solution and M23C6 carbide precipitations was found.

Parameters to measure nonlinearity in polymethylmethacrylate (PMMA) and carbon fiber reinforced polymer (CFRP) materials have been determined with nonlinear ultrasound (NLUS). The nonlinear parameter &beta, has been determined using the variation of the Finite Amplitude Method (FAM) with harmonic generation. Using this as a reference, the first contribution of this work consists of deducting the experimental configuration necessary to measure this nonlinear parameter in a correct and feasible way. Excitation level, frequency of the wave generated, number of cycles analysed and the distances transducer-specimen and specimen-hydrophone have been determined in both materials. The second contribution is a semi-analytical model that allows to obtain the nonlinear parameter in materials by removing water contribution and considering geometric and viscous attenuation, using the data obtained in an immersion tank. Finally, an application of this model has been carried out in PMMA in order to determinate the nonlinear parameter in this material. From the results, we confirm that the configuration determined in this paper to obtain the parameter &beta, decreases the noise in the measurements.

WOS: 000466262700040, Effect of jet flow structures impinged on a heated cylinder has been investigated experimentally and numerically in this study. The FLUENT 6.3.26 was used to simulate this numerical problem. In the numerical section, the influence of some variables such as the distance between cylinder and jet on the fluid flow characteristics has been analyzed. The distance between the cylinders and jet has been varied as H/S = 4, 6, and 10. The flow characteristics around the heated cylinder with a diameter of 30 mm were obtained in the range of 5000, Firat University Scientific and research fund [TEKF.12.01], Authors thank Firat University Scientific and research fund for their valuable financial support with a project number TEKF.12.01.

Pregnancy involves a gradual change in tissue consistency, where, as gestational age increases a drop in stiffness is noticeable. The extracellularmatrix (ECM) of the cervixwhose behavior is controlled by the collagen structure is reconfigured, due to hormonal and protein related factors that degraded it. There is an increase in cellular andwater content.Thecollagenmaintains a stable percentage, although the synthesis-solubility interaction causes a transformation in the network increasing its diameter and waviness, which destabilizes themechanical integrity. Further understanding of the remodeling of the cervix becomes a key element in the progress against preterm birth. However, since the woman is in a very delicate state, the available information is scattered.The aim is to provide a framework where the variation of the histological properties is linked with the individual biomechanical evolution of the constituents; therefore a multiscale approach to the problem can be made. The results of different authors were reviewed to obtain values of each component depending on the gestational age, and then they were combined with the mechanical development of each variable obtained from the outputs of numerical simulations of another author. An additive function is proposed, in which the mechanical contribution of each constituent is added to a reference value established for a nonpregnant state. Results show how biochemistry models the mechanical behavior of the tissue through the histology and morphology of the ECM., This research was supported by the Ministry of Education [DPI2017-83859-R, DPI2014-51870-R, DPI2010-17065, and UNGR15-CE-3664], Ministry of Health [DTS15/00093 and PI16/00339, PI-0107-2017, PIN-0030-2017], Junta de Andalucía [P11-CTS-8089], and the European Social Fund (youth employment initiative) projects.

WOS: 000384843200007, Heat transfer enhancement in the annular fins with uniform profile is investigated in the present study. Conventional fin materials are replaced with the functionally graded materials in order to increase the rate of heat transfer and corresponding fin efficiency. Here, the fin material properties, such as conductivity, are assumed to be graded along the annular fin radius, R, as a linear function. The governing equation of the annular fin is computed with an approximate analytical method using the mean value theorem. It is revealed that the in-homogeneity index, beta, of the fin material plays an important role on the thermal characteristics of the annular fins. Alternatively, heat dissipation between the fin surface and surrounding fluid in the annular fins increases with increasing the inhomogeneity indices, beta. Finally, it is stated that application of the functionally graded material in the annular fins enhances the fin efficiency in comparison to the annular fins with homogeneous material. It is hoped that the results obtained from this study arouse interest among thermal designers and heat exchanger industries.

1st International Symposium on Materials for Energy Storage and Conversion (ESC-IS) -- SEP 07-09, 2015 -- Middle E Tech Univ, Ankara, TURKEY, WOS: 000378359400040, Extrusion is one of the most effective and inexpensive methods used in the production of ceramic tubes for tubular or micro-tubular solid oxide fuel cell (SOFC) applications. In this method, the parameters such as the viscosity of the ceramic slurry, the extrusion speed and the die temperature need to be optimized for a high performance. In this study, anode supported micro-tubular solid oxide fuel cells are successfully fabricated via a specially designed vertical-type piston extruder machine. The die design enables the production of micro-tubular SOFCs with outer diameters from 3 to 4.5 mm. The die temperature is determined to be the most important process parameter and the suitable die temperature is ranging 40-70 degrees C depending on the slurry content. The electrolyte layer is coated on the anode support tube by vacuum assist dip coating technique and co-sintering is applied with a home-made porous sintering apparatus to avoid dimensional anomalies. The effects of the parameters such as the composition of the electrolyte solution, the vacuum pressure and the immersion time on the electrolyte thickness are investigated. It is found that the electrolyte thickness decreases when the immersion time and vacuum pressure are reduced. Moreover, the thickness of the electrolyte is found to be depended on the content of the electrolyte solution. The effect of the pre-sintering temperature on the electrolyte quality is also investigated. The sintering temperatures of 1000 degrees C and 1100 degrees C provide a similar and desired electrolyte microstructure. A peak power density of 140 mW cm(-2) is obtained at 700 degrees C from the final cell. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

1st International Symposium on Materials for Energy Storage and Conversion (ESC-IS) -- SEP 07-09, 2015 -- Middle E Tech Univ, Ankara, TURKEY, WOS: 000378359400033, Solid oxide fuel cells (SOFCs) are ceramic based electrochemical devices operating at high temperatures and generates electricity and useful heat energy utilizing various fuels at a high efficiency. The main structure of the cell comprises a dense electrolyte coated with two porous anode and cathode electrodes. The electrolyte is responsible for the transfer of oxide ion while the electrochemical reactions take place in the electrodes. The cell performance is limited by the number of reaction zones known as triple/three phase boundaries (TPBs). Therefore, the electrodes play a crucial role in achieving high power as well as long service life. When the requirements that SOFC electrodes should meet are considered, the most successful electrode materials seem to be composite ones, including ionic and electronic conductive phases with pores for the gas transport. However, this combination is not enough alone since the contiguous contact of these three phases within the electrodes is also necessary to obtain electrochemically active reaction zones. The number of these areas can be a useful metric for predicting the cell performance or provide a relationship between the performance and microstructure. The determination of the electrochemical reaction zones at the micro-scale and the microstructural parameters influencing their density are required to link the microstructure to the performance. Therefore, in this paper, micro-modeling studies of SOFC electrodes through advanced microstructural characterization are reviewed. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

WOS: 000363345800042, In the numerical study, it was mainly intended to test the capability of a control rod to reduce the drag and to suppress the fluctuating forces acting on the rod-square (total) system for various angles of incidence (alpha) and center-to-center spacing ratios (L/D). The Reynolds numbers (Re) based upon the diameter of control rod and the side length of the square prism are 50 and 200, respectively, for the control rod and the square prism. Seven distinct flow patterns were observed and it was demonstrated that the cavity flow pattern is the most effective in terms of simultaneous reduction of the time-averaged and RMS values of fluctuating force coefficients for both control rod and square prism. As the control rod located 2D or 3D upstream of the square prism at zero angle of incidence, the time-averaged drag coefficient of the total system i.e. the sum of the time-averaged drag coefficients of the control rod and the square prism is about 74% that of the square prism alone. Furthermore, the maximum reductions in RMS values of the fluctuating lift acting on the total system are 53% and 60%, respectively, for 2D and 3D. On the other hand, the effectiveness of control rod in reducing the time-averaged drag coefficient of the total system was generally diminished with increasing a. Instantaneous and time-averaged flow fields were also presented in order to identify the flow patterns around the rod-square system. (C) 2015 Elsevier Ltd. All rights reserved., Scientific and Technological Research Council of Turkey (TUBITAK) [105M241], The authors gratefully acknowledge the financial support from the Scientific and Technological Research Council of Turkey (TUBITAK) for this study through grant number of 105M241.

Optimizing an experimental design is a complex task when a model is required for indirect reconstruction of physical parameters from the sensor readings. In this work, a formulation is proposed to unify the probabilistic reconstruction of mechanical parameters and an optimization problem. An information-theoretic framework combined with a new metric of information density is formulated providing several comparative advantages: (i) a straightforward way to extend the formulation to incorporate additional concurrent models, as well as new unknowns such as experimental design parameters in a probabilistic way, (ii) the model causality required by Bayes’ theorem is overridden, allowing generalization of contingent models, and (iii) a simpler formulation that avoids the characteristic complex denominator of Bayes’ theorem when reconstructing model parameters. The first step allows the solving of multiple-model reconstructions. Further extensions could be easily extracted, such as robust model reconstruction, or adding alternative dimensions to the problem to accommodate future needs.

WOS: 000429178800003, This study presents a case study of energy management in a sugar factory in Turkey. The main idea of the study is to analyse energy consumption, the quantity of material production, and figure out a suitable energy efficiency for the case study of a sugar factory subsequently. Firstly, a material production and energy consumption audit were performed for the sugar factory. Secondly, energy efficiency was calculated from the energy data. The SPSS (Statistical Package for the Social Sciences) statistical software was used to ensure the accuracy of the data. The factory's energy consumption was calculated as 43,590.25 toe (tons of oil equivalent) over the last year. These results were used for CUSUM (Cumulative Sum Deviation Method) graphics. This research poses the consumption of energy, cost of energy and the relationship between energy usage and material production of sugar. The unit of energy cost was 688.22 [$/toe] for the last year. This result showed that the factory decreased the unit of energy by optimisation. The results indicated that the investigated sugar factory should pay attention to the energy management issue in order to comply with the Energy Efficiency of Turkish Law and Directives.

WOS: 000432736400010, Flow boiling researches in enhanced geometries practiced recently have been summarized in this review. Classical approximations in macroscale flows have not applied to the flows with small hydraulic diameters, so, this subject has been paid attention by the researchers. Application areas of these structures are increasing continuously due to cooling need in small confined spaces. The related studies have been reviewed in a chronological manner and their parameters have been given in a table in order for the researchers to observe the scientific duration regarding the progresses on this subject. Almost all papers on this subject have been produced after 2000, therefore, this subject is considered as an actual one to improve and worth to study in the literature. This study can not only be evaluated as the beginning argument for the researchers involved in flow boiling process in mini and microchannel, but it also consists of new works on the investigated subject., Department of Mechanical Engineering, King Mongkut's University of Technology Thonburi; "Research Chair Grant" National Science and Technology Development Agency; Thailand Research Fund; National Research University Project, All authors would like to thank the Department of Mechanical Engineering, King Mongkut's University of Technology Thonburi for the support during this research in Thailand The authors would like to thank the "Research Chair Grant" National Science and Technology Development Agency, the Thailand Research Fund and the National Research University Project for the support.

There is a challenge in characterizing the soft tissue mechanical functionality in cylindrical geometries by current elastography techniques applied to small organs. Torsional waves are a type of shear elastic waves that propagate through soft tissue radially and in depth in a curled geometry, ideally suited to explore structures such as the cervix. Here, a sensor based on a novel arrangement of concentric sandwiches of piezo- and electromechanical elements is prototyped and tested to quantitatively assess stiffness in human cervix. The purpose is to determine the robustness of a torsional wave elastography (TWE) sensor prototype to quantify cervical stiffness, as a first step to validate a reliable measurement protocol using TWE. An array of tests designed to validate a set of hypothesis about the contact conditions were performed on up to 3 different nonpregnant voluntary women. The mechanical properties were reconstructed from the recorded TWE signals, and the outcomes were statistically analyzed to validate the contact condition hypothesis. The results suggest that, although future tests need to be performed to fully assess the repeatability and quality of the measurements, some characteristics of the measurement protocol become clear; in particular: (1) the use of speculum is recommended since it not only stabilizes the measurements, but also corrects and stabilizes the orientation of the cervical neck, and allows to visually verify the positioning and alignment of the probe, while not significantly increasing discomfort to women during this test; (2) the use of lubricant gel has no significant effect on the measurement quality; (3) 1cm off-centering from external cervical os is not acceptable; (4) a range of applied force between 500-2000 N does not significantly vary measurement signal quality, but the reconstructed value of the shear modulus does vary, probably due to its constitutive nonlinearity; (5) breathing movements affects measurements, but short duration of TWE pulse (0.3 s) allows to take measurements in apnea.

Temporomandibular joint replacement (TMJR) is a complex surgical procedure in which the artificial joints available must assure the anatomical reconstruction and guarantee a good range of the natural temporomandibular joint (TMJ) movements. With this aim, different types of TMJ prostheses, including the stock prosthetic system and custom-made prostheses, are being currently implanted. Although temporomandibular joint replacements (TMJRs) are expected to accomplish their function during a number of years, they might actually fail and need to be replaced. This paper analyzes different design factors affecting the contact stress distributions within the TMJ prosthesis interface, which are consequently involved in their deterioration and final failure of the prosthetic device. With this purpose, a numerical model based on finite elements has been carried out in order to evaluate the stress states attained in different prosthesis configurations corresponding to general types of TMJ prostheses. On the other hand, the actual degradation of resected implants has been evaluated via optical microscopy. The linkage between the numerical simulations performed and experimental evidence allowed the authors to establish the different wear and damage mechanisms involved in the failure of stock TMJ prostheses. Indeed, the results obtained show that the contact stresses at the interface between the mandible and the glenoid fossa components play a key role in the failure process of the TMJR devices.

WOS: 000356549100082, Glass ceramic composites are among the favorable candidates as a sealing material for solid oxide fuel cells (SOFC). In order to obtain a reliable, robust and hermetic sealing, the glass ceramics must chemically bond to both the metallic interconnector and the ceramic electrolyte. A high-bonding strength and good wetting, which strongly depend on the thermal treatment, are always preferred to ensure gas-tight sealing. The thermal treatment involves three stages: binder burnout (stage-I), sintering (stage-II), and cooling (stage-III). This study investigates effects of various parameters on the sealing quality at the sintering stage. The effects of sintering temperature, clamping pressure and sealant thickness are considered. The glass ceramic laminates are produced employing a tape casting method. The sealing quality is evaluated by measuring leakage and final macro-structure of the sealing region. It is suggested that a 900-930 degrees C sintering temperature and 1.5-7.6 N cm(-2) clamping pressure ranges are better for successful sealing. The initial thickness of glass ceramic laminates is also desired to be between 0.25-0.5 mm thickness range for both a cost-effective and reliable sealing. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

WOS: 000358560800002, In this study, the effects of the artificial-aging temperature and time on the mechanical properties and springback behavior of AA6061 are investigated. The results reveal that the yield strength, the tensile strength and the elongations decreased with the increasing artificial-aging temperature, but increased with the increasing artificial-aging time up to the peak age. The springback of the alloy increased significantly with the increasing artificial-aging time at the artificial-aging temperature ranging from 160 degrees C to 180 degrees C and decreased with the artificial-aging time at 200 degrees C. The springback angle in the as-received condition is lower than in all the aged conditions.

A novel torsional wave sensor designed to characterize mechanical properties of soft tissues is presented in this work. Elastography is a widely used technique since the 1990s to map tissue stiffness. Moreover, quantitative elastography uses the velocity of shear waves to achieve the shear stiffness. This technique exhibits significant limitations caused by the difficulty of the separation between longitudinal and shear waves and the pressure applied while measuring. To overcome these drawbacks, the proposed torsional wave sensor can isolate a pure shear wave, avoiding the possibility of multiple wave interference. It comprises a rotational actuator disk and a piezoceramic receiver ring circumferentially aligned. Both allow the transmission of shear waves that interact with the tissue before being received. Experimental tests are performed using tissue mimicking phantoms and cervical tissues. One contribution is a sensor sensitivity study that has been conducted to evaluate the robustness of the new proposed torsional wave elastography (TWE) technique. The variables object of the study are both the applied pressure and the angle of incidence sensor–phantom. The other contribution consists of a cervical tissue characterization. To this end, three rheological models have fit the experimental data and a static independent testing method has been performed. The proposed methodology permits the reconstruction of the mechanical constants from the propagated shear wave, providing a proof of principle and warranting further studies to confirm the validity of the results., This research was supported by the Ministry of Education DPI2014-51870-R, DPI2010-17065 and UNGR15-CE-3664, Ministry of Health DTS15/00093 and PI16/00339, and Junta de Andalucía P11-CTS-8089 projects. Modesto T. López-López acknowledges financial support by the project FIS2013-41821-R (Ministry of Economy and Competitiveness, co-funded by the ERDF, European Union). We acknowledge the collaboration of the members of the Anatomical Pathology Unit of the University Hospital Complex of Granada. Finally, Antonio Callejas is grateful to the University of Granada for the award of an PhD fellowship.

Copper direct bonding technology is considered to be one of the most promising approaches for matching the miniaturization needs in future tridimensional integrated high performance circuits (3D-IC). However, the bonding mechanism of copper surfaces with an initial dishing effect, induced by the polishing step, must be investigated in order to optimize the adhesion process and prevent further reliability issues. In this study, we present thermomechanical finite element simulations of Cu–SiO 2 hybrid bonding with account for the annealing step and various amplitudes of the initial dishing. A cohesive model that mimics nonlinear interactions between Cu/Cu and SiO 2 /SiO 2 interfaces and related bonding mechanism is implemented within a nonlinear contact mechanics strategy. The bonding process along with the influence of the annealing conditions and the copper plastic response on the closure of the Cu/Cu interface are investigated.

WOS: 000395600700002, Observations are reported on a carbon black reinforced thermoplastic elastomer in multistep uniaxial tensile cyclic tests with a mixed deformation program (oscillations between maximum elongation ratios k(max) and various minimum stresses Amin with km, monotonically increasing with number of cycles n). Fading memory of deformation history is demonstrated: when specimens are subjected to two loading programs that differ along the first n 1 cycles of deformation and coincide afterwards, their stress strain diagrams become identical starting from the nth cycle. A constitutive model is developed in cyclic viscoplasticity with finite deformations, and its adjustable parameters are found by fitting the observations. Ability of the stress strain relations to describe the fading memory phenomenon and to predict the mechanical response of polymer composites in multi-step cyclic tests with large strains is confirmed by numerical simulation. (C) 2016 Elsevier Ltd. All rights reserved.

WOS: 000415695400013, This contribution presents an approach for the modeling and prediction of surface roughness in the turning of AZ91D magnesium alloys using an artificial neural network. The experiments were conducted with CCGT, DCGT and VCGT cutting tools under minimum quantity lubrication and dry machining conditions. AZ91D alloys were machined at different cutting speeds and feed rates, and the depth of cut was kept constant. 15 out of 18 experimental data points were used for the training of the artificial neural network model and the remaining 3 were used for the testing process. The average percentage error was calculated as 0.000815 % and 0.663 % for training and testing, respectively. The model and target results were found to have extremely low error rates.

WOS: 000397033700001, Experimental data are reported on poly(lactic acid) (PLA) in tensile loading-unloading tests and relaxation tests under stretching and retraction at temperatures ranging from room temperature up to 508C. Two characteristic features of the time-dependent response of PLA are revealed: (i) with a decrease in minimum stress under retraction at a fixed temperature, relaxation curves change their shape from monotonically decaying with time (simple relaxation), to non-monotonic (mixed relaxation) to monotonically increasing (inverse relaxation) and (ii) with an increase in temperature, inverse relaxation after unloading down to the zero stress evolves into mixed relaxation with a pronounced shift of the peak position to smaller relaxation times. Constitutive equations are derived for the mechanical behavior of PLA, and adjustable parameters in the stress-strain relations are found by fitting the observations. Ability of the model to predict the time-dependent response under cyclic deformation is confirmed by numerical simulation. (C) 2016 Society of Plastics Engineers, European Research Council [314744], Contract grant sponsor: European Research Council through FP7-NMP Programme; contract grant number: 314744.

WOS: 000397548700004, In this study, for active control of flow, the effect of the Dielectric Barrier Discharge (DBD) plasma actuator consisting of intermittent electrodes in the lengthwise direction of circular cylinder is investigated. The experiments were conducted in the wind tunnel at the Reynolds numbers between 6000 and 12,500. In three different cases, the lengths of the actuators and gaps between them are chosen as 20 mm, 25 mm, and 50 mm, respectively. The applied voltage is in the range of 4.5-7.5 kVpp and the constantly applied frequency is 3.5 kHz for producing the plasma. By using the equally placed DBD plasma actuators for the circular cylinder, 2 dimensional flow structure in the wake region is converted into 3-dimensional flow structure that leads to reduce in the mean and fluctuating forces acting on the cylinder. The wake region is narrower than the plain cylinder at the middle point of the electrode spanwise position and the width of the wake region increases at the end point of the electrode spanwise position., Scientific and Technological Research Council of Turkey (TUBITAK) [110M056], The authors would like to acknowledge the financial support of this work by the Scientific and Technological Research Council of Turkey (TUBITAK) under the Contract number of 110M056.

11th International Conference on Technology of Plasticity (ICTP) -- OCT 19-24, 2014 -- Nagoya, JAPAN, WOS: 000358994000125, In recent years, numerous researchers have reported that the predicted forming limit diagrams strongly depend on the method of determining the material parameters used in the yield functions and the corresponding the shape of the yield surface. In this study, the capability of different yield functions to predict the forming limit diagram of DP600 advanced high strength steel sheet is investigated. Additionally, the effects of determination method of the anisotropic parameters on the forming limit diagram are studied. The yield functions proposed by Hill-48, Barlat-89, and YLD2000-2d are considered and the forming limit diagrams are constructed using the Marciniak Kuczynski model. Results reveal that predictions using different yield functions are lower than the experimental forming limits. In terms of shape and tendency, the YLD2000-2d curve is best suited for representing experimental curve. (C) 2014 Published by Elsevier Ltd.

Conference on High Temperature Experimental Techniques and Measurements at the 224th Electrochemical-Society Meeting (ECS) -- OCT 27-NOV 01, 2013 -- San Francisco, CA, WOS: 000329694100013, In this study, thermodynamic and heat transfer concepts were combined to understanding correlation of heat, power and temperature gradient on the cell. All of heat sources and amounts has been determined for electrolyte supported SOFC having 81 cm(2) active area and thus temperature gradient due to each heat source can computed and total temperature distribution clearly has been shown. For this, electrochemical, ohmic, activation and concentration polarization heat sources have been computed by using the boundary conditions taken from the experimental data such as current-voltage-power and mol fraction. Then 80% of the heat generated at 0.7 V and 700 degrees C was removed by the heat transfer and then the maximum temperature difference is found less than 6 degrees C. Also, it was found that the electrical and the heat generations are 25.41 and 23.03 W, respectively., Electrochem Soc, Electrochem Soc, High Temp Mat Div, Electrochem Soc, Energy Technol Div, Electrochem Soc, Phys & Analyt Electrochemistry Div

WOS: 000320831300012, The mechanical properties of commercial dual phase (DP), transformation induced plasticity (TRIP), and high strength low alloy (HSLA-340) steel sheets are investigated and compared at various strain rates ranging from 0.0017 to 0.17 s(-1) at ambient temperature. TRIP steel outperforms the other two materials, having comparable ductility and twice as large strength relative to DP steel. TRIP has larger strength and much larger ductility than HSLA-340. The exceuent ductility of TRIP800 is due to its high strain hardening capability, which promotes stable plastic deformation. It is observed that the strain hardening rate in TRIP800 does not decrease to zero at failure, as common in most materials in which failure is preceded by necking.

WOS: 000319271200007, In the present study, the potential of rectangular fins with 30A degrees and 90A degrees angle and 10 mm offset from the horizontal direction for heat transfer enhancement in a plate fin heat exchanger is numerically evaluated with conjugated heat transfer approach. The rectangular fins are mounted on the flat plate channel. The numerical computations are performed by solving a steady, three-dimensional Navier-Stokes equation and an energy equation by using Fluent software program. Air is taken as working fluid. The study is carried out at Re = 400 and inlet temperatures, velocities of cold and hot air are fixed as 300, 600 K and 1.338, 0.69 m/s, respectively. Colburn factor j versus Re design data is presented by using Fluent. The results show that the heat transfer is increased by 10 % at the exit of channel with fin angle of 30A degrees when compared to channel without fin for counter flow. The heat transfer enhancement with fins of 30A degrees and 90A degrees for different values of Reynolds number with 300, 500 and 800 and for varying fin heights, fin intervals and also temperature distributions of fluids on the top and bottom surface of the channel are investigated for parallel and counter flow.

WOS: 000371948400092, In this study, the effects of operation conditions on the performance of a polymer electrolyte membrane fuel cell are investigated and the results are presented together with a comprehensive literature review on the related topics. The cells with 25 cm(2) active area are tested for different inlet gas humidification levels and inlet temperatures, operating temperatures and oxidant type. The cells are characterized by the performance curves together with the cell resistance measurements. The results indicate that the humidification of the inlet gases positively affect the cell performance. However, the improvement in the cell performance is higher when the cathode gas is humidified. In addition, the operating temperature and the inlet gas temperatures are found to be the most significant parameters. The cell performance tends to increase significantly with increasing the operating and inlet gas temperatures. The effect of the oxidant type is also considered and the cell tested with pure oxygen shows slightly higher performance. (C) 2016 Elsevier Ltd. All rights reserved.

WOS: 000369462100085, Besides the general advantages of fuel cells, including clean and quiet operation, solid oxide fuel cells (SOFCs) as being one of the high-temperature fuel cells also provide a relatively high efficiency due to enhanced reaction kinetics at high operating temperatures, The high operation temperature of SOFC also enables internal reforming of most hydrocarbons and can tolerate small quantities of impurities in the fuel. However, a high operation temperature limits the SOFC application areas to stationary applications because of a long start-up period and also is not desirable from the viewpoint of cost reduction and longterm stability especially for the cell materials. Therefore, the lowering the operation temperature of SOFCs is crucial for the cost reduction and the long term operation without degradation as well as the commercialization of the SOFC systems. The reduced operating temperature also helps to reduce the time and to save the energy required for the system start-up enabling SOFCs to have wider application areas including mobile/portable ones. Apart from the low operating temperature, the high performance along with a small volume is another requirement for SOFC to be used in mobile applications. Both can be achieved by fabricating novel SOFCs generating a high power output at low operating temperatures. Therefore, this paper reviews the current status and related research on the development of these high performance-SOFC cell/stack designs. (C) 2015 Elsevier Ltd. All rights reserved.

WOS: 000391292400007, In this study, a Taguchi model was formed for the three point bending test behaviors of aluminum honeycomb composite structures. Effect of the three independent variables (cell width, cell height and adhesive) on the dependent variable (bending forces) was determined using mix design L16(4*1 2*2) orthogonal series. As a result of the experiments, bending force values were measured. As a result of Taguchi analysis according to ' better than most' solution approach, bending force value was concluded to be optimum with the use of 58.59 S/N ratio A1 B2 C1 level namely, primary 6.78 mm for cell width and secondary 30 mm for cell height and primary epoxy adhesive. Order of importance according to S/N answer table for force factor was ordered as cell width, cell height and adhesive. 95% was significant for the force values of the factor and levels selected in ANOVA results., Coordinatorship of Selcuk University's Scientific Research ProjectsSelcuk University [13201066, 15401026, 15401128], This work was supported Coordinatorship of Selcuk University's Scientific Research Projects (Project number: 13201066, 15401026 and 15401128).

1st International Symposium on Materials for Energy Storage and Conversion (ESC-IS) -- SEP 07-09, 2015 -- Middle E Tech Univ, Ankara, TURKEY, WOS: 000378359400039, Solid oxide fuel cells (SOFCs) generate clean energy via electrochemical reactions at high operating temperatures. The distribution of the electrochemical reactions in the cell depends on the flow field design of the interconnectors. The non-uniform distribution of the reactions due to the flow field design may cause the development of thermal stresses which may lead to micro or macro cracks in the cell and thus a significant performance loss even a cell failure. In this study, the effects of operating current densities and fuel flow rates on the temperature profile within the cell and the cell performance are experimentally investigated for two different flow-field designs with Crofer 22 APU interconnectors, i.e. Design I and Design II. Design I, which mimics the conventional interconnector structure, has machined gas channels and porous nickel mesh at the anode side for the distribution of hydrogen and the collection of the current generated in the cell while at the anode side of Design II, only wire woven nickel mesh is employed. The experimental results indicate that Design II provides much more uniform temperature distributions under 20-40 A current loads and 1-2 NL/min H-2 flow rates when compared to those of Design I. Furthermore, Design II exhibits a higher peak power density than Design I at an operation temperature of 800 degrees C. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

WOS: 000376483000009, Laser beam welding is an indispensable and preferable method which is widely used in the automotive industry. It satisfies the requirements of low cost, short processing time, and high quality. Although laser welding finds applications in different industries, its application in the automotive industry requires further investigation. In this paper, the current status of laser beam welding applications in automotive industry is reviewed and recent developments are discussed. This review study reveals that LASER BEAM WELDING is an important process for automotive industry, therefore it will become a more prominent method in upcoming years., Nigde University in Turkey; Petroleum Institute in Abu Dhabi; King Fahd University of Petroleum and Minerals Dhahran, Saudi Arabia, The authors acknowledge the support of Nigde University in Turkey and The Petroleum Institute in Abu Dhabi during the course of this work. The authors also acknowledge the support of King Fahd University of Petroleum and Minerals Dhahran, Saudi Arabia.

10th Anniversary International Conference on Experimental Fluid Mechanics -- NOV 17-20, 2015 -- Prague, CZECH REPUBLIC, WOS: 000400395300106, A promising novel actuator called Spark-Plug Plasma Synthetic Jet (SPSJ) has been developed in Atmospheric Plasma Research Laboratory at Nigde University. It generates electrothermally high synthetic jet velocity by using high voltage. SPSJ actuator can be utilized to be an active flow control device having some advantages such as no moving parts, low energy consumption and easy to integrate the system. This actuator consists of two main components: semi-surface spark plug (NGK BUHW) as an anode electrode and a cap having an orifice as a cathode electrode. The cap, having a jet exit orifice diameter of 2 mm, has diameter of 4.4 mm and height of 4.65 mm. This study presents the characteristics of SPSJ actuator by using the hot wire anemometer in order to approximately determine jet velocity in quiescent air. Peak velocity as high as 180 m/s was obtained for f(e) = 100 and duty cycle 50%. The flow visualization indicated that the actuator's jet velocity is enough to penetrate the developed boundary layer., DANTEC Dynam GmbH, LAVISION, LENAM, MECAS ESI s r o, MIT s r o, TSI GmbH, Scientific and Technological Research Council of Turkey (TUBITAK) [213M179], The authors would like to acknowledge the financial support of this work by the Scientific and Technological Research Council of Turkey (TUBITAK) under the Contract Number of 213M179.

ASME International Mechanical Engineering Congress and Exposition (IMECE2015) -- NOV 13-19, 2015 -- Houston, TX, WOS: 000379702900036, In recent years, the use of optimization methods in sheet metal forming has been increased remarkably. In the finite element simulation of the sheet metal stamping operations, the model parameters are determined from the several tests like tensile, compression, and biaxial stretching tests (bulge test). In this study, Yld2000-2d anisotropic yield function parameters are determined for DP800 advanced high strength steel using a 60 degrees V-shaped die bending process. The difference between the simulation and experiment is found to be 1 degree using the classical determination method of the anisotropy parameters. The difference is 0.1 degree using the optimization method., ASME

WOS: 000374803100005, Recently, nanofluids have been studied extensively by the researchers as a result of the developments in nano technology. It is essential for researchers to know nanofluids' physical properties in order to make calculations regarding their specific research topics. Determination of viscosity issue is an actual one due to its common usage in heat transfer and thermodynamics. In this study, graphite particles are selected to have nanofluid mixture with its base fluid of pure water. Their volumetric concentrations are varied from 0 to 2% in pure water. Once the stabilized nanofluid is prepared by a sonicator and ultrasonic bath, viscosity is measured by a viscosity meter for the temperatures ranging from 20 degrees C to 60 degrees C. Validation of the experiments have been done by means of the comparison of them with the 32 empirical correlations in the literature. Then, Artificial Neural Network (ANN) analyses have been performed in order to have better empirical correlation than those in the literature. Furthermore, detailed information on the preparation nanofluids, measurement of viscosity, a list of measured data, numerical model by Matiab software, and alteration of viscosity with temperature and concentration have been given in the paper. It was concluded that viscosity correlations in the literature can predict different types of nanofluids' viscosity although they have been derived using specific type and diameter of nano particles and their base fluids. (C) 2016 Elsevier Ltd. All rights reserved., King Mongkut's University of Technology Thonburi; "Research Chair Grant" National Science and Technology Development Agency; Thailand Research Fund; National Research University Project, All authors would like to thank King Mongkut's University of Technology Thonburi for the support during this research in Thailand. In addition, all authors would like to thank the "Research Chair Grant" National Science and Technology Development Agency, the Thailand Research Fund and the National Research University Project for the support.

WOS: 000307027300044, In order to enhance the electrochemical performance and reduce the operation temperature of a conventional electrolyte supported solid oxide fuel cell (SOFC), a three layered electrolyte with various geometry is designed and fabricated. Novel three layered electrolytes comprise a dense and thin scandia alumina stabilized zirconia (ScAlSZ) electrolyte layer sandwiched between two hallow ScAlSZ electrolyte layers each having the same thickness as the support but machined into a filter like architecture in the active region with circular, rectangular and triangular cut off patterns. The percent of thin electrolyte layer in the active region is kept constant as 30% for all designs in order to investigate the effect of pattern geometry on the mechanical properties and the performance of the electrolytes. Single cells based on novel electrolytes are manufactured and electrochemical properties are evaluated. A standard electrolyte and electrolyte supported cell are also fabricated as a base case for comparison. Although the electrolyte having triangular patterns has the highest peak power at all operation temperatures considered, it exhibits the lowest flexural strength. (c) 2012 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

WOS: 000303122900009, A numerical analysis of the process of jet drying of a moist cylinder was conducted. The drying jet was a laminar 2D jet stationed at three different distances (D/H = 0.22, 0.25, and 0.33) from the moist cylinder to investigate the jet effectiveness on heat and mass transfer. The diameter of the object and initial jet height were fixed in all cases. Temperature and mass distributions were obtained inside the object for different jet velocities. A finite volume method was used to solve the governing equations for momentum and energy with a commercial code. Calculations were performed for three different Reynolds numbers, namely, Re = 100, 200, and 300. It was found that heat and mass transfer increased with decreasing the distance, D/H, between the jet and the cylinder. In addition, increasing Reynolds number showed a positive effect on heat and mass transfer. Locally, jet drying was found to be most effective near the stagnation point on the leading side of the cylinder.