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The use of green roofs, a low-impact development practice, can be an effective means of reducing direct runoff in urban centers. Green roof modeling can enable efficient design by preliminarily grasping the behavior of the green roof system according to specific configurations. In this study, we aimed to find appropriate evapotranspiration and parameter optimization schemes for HYDRUS-1D, a commonly used modeling tool for green roofs. Comparative studies of this sort in the context of green roof runoff modeling have not been conducted previously and are important in guiding users to overcome the difficulties of choosing the right numerical schemes for an accurate prediction of runoff from a green roof. As a study site, the Portland Building Ecoroof in Portland, Oregon, USA, was chosen, as green roof configurations and observed data for climate and runoff were available. From the simulation results of the runoff volume, the Blaney–Criddle method, which was considered an alternative, was found to be appropriate for calculating evapotranspiration from a green roof (R2 = 0.82) relative to the Hargreaves method built in HYDRUS-1D (R2 = 0.46). In addition, this study showed that the optimization method using the harmony search algorithm, which was proposed as an alternative optimizer, was better (R2 = 0.95) than that of the HYDRUS-1D's own optimization module (R2 = 0.82) in calibrating HYDRUS-1D for green roof runoff. The findings are thought to be useful in guiding modelers who are considering using HYDRUS-1D for green roof runoff simulations. [ABSTRACT FROM AUTHOR]

Ultrasound B-scan images are traditionally formed from the envelope of the received radiofrequency echoes, but the image texture is dominated by granular speckle patterns. Longstanding efforts at speckle reduction and deconvolution have been developed to lessen the detrimental aspects of speckle. However, we now propose an alternative approach to estimation (and image rendering) of the underlying fine grain scattering density of tissues based on power law constraints. The key steps are a whitening of the spectrum of the received signal while conforming to the original envelope shape and statistics, followed by a power law filtering in accordance with the known scattering behavior of tissues. This multiple step approach results in a high-spatial-resolution map of scattering density that is constrained by the most important properties of scattering from tissues. Examples from in vivo liver scans are shown to illustrate the change in image properties from this framework.

Ultrasound B-scan images are traditionally formed from the envelope of the received radiofrequency echoes, but the image texture is dominated by granular speckle patterns. Longstanding efforts at speckle reduction and deconvolution have been developed to lessen the detrimental aspects of speckle. However, we now propose an alternative approach to estimation (and image rendering) of the underlying fine grain scattering density of tissues based on power law constraints. The key steps are a whitening of the spectrum of the received signal while conforming to the original envelope shape and statistics, followed by a power law filtering in accordance with the known scattering behavior of tissues. This multiple step approach results in a high-spatial-resolution map of scattering density that is constrained by the most important properties of scattering from tissues. Examples from in vivo liver scans are shown to illustrate the change in image properties from this framework. [ABSTRACT FROM AUTHOR]

Laser drilling cooling holes into turbine components is well established in industries. However, there are drawbacks related to setting and maintaining the appropriate manufacturing conditions, which can be formulated as an inverse problem. The inverse solution of a physical model describing long-pulse laser drilling of sheet metal is learned through an artificial algorithm. The trained feed-forward neural network predicts process parameters of desirable production outcomes. Here, the trained network predicts beam radius and pulse power to drill through getting a hole with specified conicity. The hyperparameters of the neural network are trained using algorithmic differentiation. Using a physical model improves the solvability of the inverse problem, since all trials during training belong to the applicable range of laser drilling and improves the training procedure going in a physically informed direction. [ABSTRACT FROM AUTHOR]

In this study, a hybrid type (2-PUR/UPS) &R cervical vertebra rehabilitation machine is proposed for the cervical traction rehabilitation training of patients with cervical spondylosis. The machine has 3R1T four degrees of freedom and meets the requirement of the range of motion of human cervical vertebra. The kinematic performance of the machine is analyzed to verify whether it can be applied in the field of human cervical vertebra rehabilitation. Firstly, the degrees of freedom of the mechanism are solved and verified by using the spiral theory and the modified Kutzbach-Grvble formula. Secondly, by solving the inverse solution of the position of the mechanism, the rod length of the mechanism is deduced, the program of solving the workspace is written, and the workspace of the mechanism is obtained by the numerical search method. Finally, the mechanism is simulated and analyzed by Adams software. The results show that the mechanism could reach the range required for cervical spine movement, including -55° to 35° for forward and backward leaning. Left-handed and right-handed is -52° to 52°; the left and right lateral flexion is -45° to 45°, which can provide traction treatment for patients with cervical spondylosis.

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This high density EEG report dissects the neural processing in the visual perspective taking using four experimental comparisons (Arrow, Avatar and Self, Other). Early activation differences occurred between the Avatar and the Arrow condition in primary visual pathways concomitantly with alpha and beta phase locked responses predominant in the Avatar condition. In later time points, brain activation was stronger for the Avatar condition in paracentral lobule of frontal lobe. When taking the other's perspective, there was an increased recruitment of generators in the occipital and temporal lobes and later on in mentalizing and salience networks bilaterally before spreading to right frontal lobe subdivisions. Microstate analysis further supported late recruitment of the medial frontal gyrus and precentral lobule in this condition. Other perspective for the Avatar only showed a strong beta response located first in left occipito-temporal and right parietal areas, and later on in frontal lobes. Our EEG data support distinct brain processes for the Avatar condition with an increased recruitment of brain generators that progresses from primary visual areas to the anterior brain. Taking the other's perspective needs an early recruitment of neural processors in posterior areas involved in theory of mind with later involvement of additional frontal generators. [ABSTRACT FROM AUTHOR]

In this study, the inverse solution with a single dipole was computed to localize the premature ventricular contraction (PVC) origin from long term multiple leads ECG measurements on fourteen patients. The stability of the obtained results was studied with respect to the preprocessing of signals used as an input to the inverse solution and the complexity of the torso model. Two methods were used for the baseline drift removal. After an averaging of the heartbeats, the influence of the retention or elimination of the remaining offset at the beginning of the PVC signal was examined. The inverse computations were performed using both homogeneous and inhomogeneous patient-specific torso models. It was shown that the remaining offset in the averaged signals at the beginning of the PVC signal had the most significant impact on the stability of the resulting position within the ventricles. Its elimination stabilizes the location of the results, decreases the sensitivity to the torso model complexity and decreases the sensitivity to the primary baseline drift removal method. The additional offset correction decreased the mean distance between the results for all patients from 17-18 mm to 1-2 mm, regardless of the baseline drift removal method or the torso model complexity.

The inverse problem of electrocardiography or electrocardiographic imaging (ECGI) is a technique for reconstructing electrical information about cardiac surfaces from noninvasive or non-contact recordings. ECGI has been used to characterize atrial and ventricular arrhythmias. Although it is a technology with years of progress, its development to characterize atrial arrhythmias is challenging. Complications can arise when trying to describe the atrial mechanisms that lead to abnormal propagation patterns, premature or tachycardic beats, and reentrant arrhythmias. This review addresses the various ECGI methodologies, regularization methods, and post-processing techniques used in the atria, as well as the context in which they are used. The current advantages and limitations of ECGI in the fields of research and clinical diagnosis of atrial arrhythmias are outlined. In addition, areas where ECGI efforts should be concentrated to address the associated unsatisfied needs from the atrial perspective are discussed. [ABSTRACT FROM AUTHOR]

This high density EEG report dissects the neural processing in the visual perspective taking using four experimental comparisons (Arrow, Avatar and Self, Other). Early activation differences occurred between the Avatar and the Arrow condition in primary visual pathways concomitantly with alpha and beta phase locked responses predominant in the Avatar condition. In later time points, brain activation was stronger for the Avatar condition in paracentral lobule of frontal lobe. When taking the other’s perspective, there was an increased recruitment of generators in the occipital and temporal lobes and later on in mentalizing and salience networks bilaterally before spreading to right frontal lobe subdivisions. Microstate analysis further supported late recruitment of the medial frontal gyrus and precentral lobule in this condition. Other perspective for the Avatar only showed a strong beta response located first in left occipito-temporal and right parietal areas, and later on in frontal lobes. Our EEG data support distinct brain processes for the Avatar condition with an increased recruitment of brain generators that progresses from primary visual areas to the anterior brain. Taking the other’s perspective needs an early recruitment of neural processors in posterior areas involved in theory of mind with later involvement of additional frontal generators.

Ultrasound measurements are a widely used instrument in clinical practice. For later traceability of the images, the position (and orientation) of the ultrasound probe must be recorded during the measurement. Until now this has to be done manually by the physician. An easier and more accurate approach would be the automatic tracking of the ultrasound probe. This contribution shows a first approach for automatically localizing the ultrasonic head during measurement. The proposed method is based on coils surrounding the patient bed and a 3D magnetic sensor placed on the ultrasound head. Besides some pre- and postprocessing steps, the proposed localization algorithm is based on trilateration followed by a least mean squares approach for refinement of the estimation. In a first proof-of-concept measurement with fixed positions and orientations of the ultrasound head a mean accuracy of 2.85 cm and 8.94 ◦was achieved. Additionally, a measurement with a moving ultrasound head is presented to demonstrate the real-time capability of the system. Finally, future steps for improving the automatic measurement are discussed, including a graphical user interface for the physician and the use of magnetoelectric sensors for measurement.

Heat transport when two surfaces of solids come into contact is an important phenomenon in many metallurgical processes. Determining the boundary conditions of heat transfer allows to obtain the correct solutions of the heat conduction equation. The paper presents models for determining the heat transfer coefficient between steel materials in contact. Experimental tests were carried out to measure the temperature changes of the contacting samples made of steel S235 (1.0038) and steel 15HM (1.7335) under the pressure of 10, 15 and 20 MPa. There was a large temperature difference between the samples. The results of the experiment were compared with numerically calculated temperatures and the value of the heat transfer coefficient was determined at different pressure values depending on the time.

Along with the study of brain activity evoked by external stimuli, the past two decades witnessed an increased interest in characterizing the spontaneous brain activity occurring during resting conditions. The identification of connectivity patterns in this so-called ''resting-state'' has been the subject of a great number of electrophysiology-based studies, using the Electro/Magneto-Encephalography (EEG/MEG) source connectivity method. However, no consensus has been reached yet regarding a unified (if possible) analysis pipeline, and several involved parameters and methods require cautious tuning. This is particularly challenging when different analytical choices induce significant discrepancies in results and drawn conclusions, thereby hindering the reproducibility of neuroimaging research. Hence, our objective in this study was to shed light on the effect of analytical variability on outcome consistency by evaluating the implications of parameters involved in the EEG source connectivity analysis on the accuracy of resting-state networks (RSNs) reconstruction. We simulated, using neural mass models, EEG data corresponding to two RSNs, namely the default mode network (DMN) and dorsal attentional network (DAN). We investigated the impact of five channel densities (19, 32, 64, 128, 256), three inverse solutions (weighted minimum norm estimate (wMNE), exact low-resolution brain electromagnetic tomography (eLORETA), and linearly constrained minimum variance (LCMV) beamforming) and four functional connectivity measures (phase-locking value (PLV), phase-lag index (PLI), and amplitude envelope correlation (AEC) with and without source leakage correction), on the correspondence between reconstructed and reference networks. We showed that, with different analytical choices related to the number of electrodes, source reconstruction algorithm, and functional connectivity measure, high variability is present in the results. More specifically, our results show that a higher number of EEG channels significantly increased the accuracy of the reconstructed networks. Additionally, our results showed significant variability in the performance of the tested inverse solutions and connectivity measures. Such methodological variability and absence of analysis standardization represent a critical issue for neuroimaging studies that should be prioritized. We believe that this work could be useful for the field of electrophysiology connectomics, by increasing awareness regarding the challenge of variability in methodological approaches and its implications on reported results.

In the present study, the three-parameter one-dimensional vertical infiltration equation recently proposed by Poulovassilis and Argyrokastritis is examined. The equation includes the saturated hydraulic conductivity (Ks), soil sorptivity (S), and an additional parameter c; it is valid for all infiltration times. The c parameter is a fitting parameter that depends on the type of porous medium. The equation is characterized by the incorporation of the exact contribution of the pressure head gradient to flow during the vertical infiltration process. The application of the equation in eight porous media showed that it approaches to the known two-parameter Green–Ampt infiltration equation for parameter c = 0.300, while it approaches to the two-parameter infiltration equation of Talsma–Parlange for c = 0.750, which are the two extreme limits of the cumulative infiltration of soils. The c parameter value of 0.500 can be representative of the infiltration behavior of many soils for non-ponded conditions, and consequently, the equation can be converted into a two-parameter one. The determination of Ks, S, and c using one-dimensional vertical infiltration data from eight soils was also investigated with the help of the Excel Solver application. The results showed that when all three parameters are considered as adjustment parameters, accurate predictions of S and Ks are not achieved, while if the parameter c is fixed at 0.500, the prediction of S and Ks is very satisfactory. Specifically, in the first case, the maximum relative error values were 33.29% and 39.53% for S and Ks, respectively, while for the second case, the corresponding values were 13.25% and 17.42%. [ABSTRACT FROM AUTHOR]

Excessive exploitation of groundwater has hitherto led to a significant land subsidence in a considerable number of plains in Iran. The compaction of aquifer layers ends up with changes in aquifer parameters, including hydraulic conductivity (Kx), specific yield (Sy), and compressibility (α). Accordingly, a precise estimation of aquifer parameters, Kx, Sy, and α seems essential for future water resources planning and management. In this study, an innovative inversion solution based on the combination of lattice Boltzmann method (LBM) and genetic algorithm (GA) was developed to determine the aquifer parameters, Kx, Sy, and α in Darab plain (in Fars province, Iran), which is highly subject to land subsidence. Herein, a newly developed LBM for unconfined groundwater flow was employed by incorporating the amount of subsidence measured by synthetic aperture radar interferometry (InSAR) spanning from 2010 to 2016. In order to optimize the aquifer parameters, the whole process of inverse modeling is replicated on the annual basis from 2010 to 2016 which leads to the temporal estimation of the aquifer parameters. Due to the compaction occurring in the aquifer system, a declining temporal trend is observed in the aquifer parameters in most parts of the plain. By fitting a function to time-dependent aquifer parameters, Kx, Sy, and α, their corresponding values and consequently the amount of subsidence in the near future, i.e., 2017, are predicted. The small average relative error (~ 3.5%) between the predicted land subsidence and the InSAR measurements demonstrates the high performance of the proposed inverse modeling approach. [ABSTRACT FROM AUTHOR]

Diffuse optical tomography (DOT) is promising to investigate functional and structural information in biological tissue by involving the forward problem and inverse solution. The work within this study develops an image reconstruction algorithm based on frequency-domain DOT using multi-frequency. In the forward problem, numerical simulation performs a diffusion equation to compute the light radiance distribution inside the model geometry with the assumed light intensity and optical properties. While in inverse solution, the absorption and reduced scattering coefficients are reconstructed utilizing light boundary data. To test the algorithm, several simulation cases, such as different contrast ratios between background and inclusion, inclusion size, as well as single and multi-frequency using one to three frequencies each and simultaneously are implemented. For verifying the image reconstruction results of multi-frequency, an objective numerical assessment, namely contrast and size detail is applied with a threshold value to specify the visible inclusion inside the geometry. Reconstructed images indicate that the effectivity of two frequencies in multi-frequency with 100 and 150 MHz has similar results as in single-frequency with 200 MHz. Therefore, the more number of frequencies may not enhance the contrast and image quality.

In order to solve the problem in master-slave heterogeneous teleoperation systems, which is that the inverse solution of robot cannot be achieved when the mapped wrist joint exceeds the reachable space of robot wrist joint, a master-slave heterogeneous mapping method based on link pose constraint is proposed. The link pose constraint means that the position and orientation of robot hand link are the same or similar to that of exoskeleton hand link. In the proposed method, the link pose constraint is used in an exoskeleton-based heterogeneous teleoperation system to realize consistent mapping between the exoskeleton and robot hand link inside wrist joint reachable space, and to realize effective inverse solution and consistent mapping of the end effector (EE) outside the reachable space. A simulation was performed by using the proposed method. The simulation results show that the proposed method can effectively realize the mapping between the exoskeleton and robot in the reachable space of robot EE. The teleoperation experimental setup was constructed by using the developed exoskeleton and an industrial robot, and the verification experiments of the proposed mapping method were performed. The experimental results indicate that the position error of the proposed heterogeneous mapping method is 0.48 mm. The experimental results demonstrate that the proposed mapping method can effectively realize master-slave heterogeneous mapping and realize continuous motion control of the teleoperation system, which satisfies the application requirements of human-robot integration, robot skill enhancement, and robot skill learning.

Today, mechanical tracking systems are becoming increasingly compact, enabling a new range of civil and military applications. These include aerial laser scanning, for which Risley prisms are used. In Risley systems, the so-called inverse problem, which focuses on obtaining the angles of the prisms for a given target coordinate, has not yet been solved mathematically. As a consequence, approximate approaches have been used, but the solutions obtained have significant errors and a lack of precision. To improve accuracy, iterative methods, which are computationally intensive, have also been implemented. In this paper, an analytical process which we call the geometric method is presented, and we verified that this strategy highly improves accuracy and computational speed. Using this method in an iterative process gives accuracies of up to 1 pm in only three iterations. This high accuracy would allow the geometric method to be applied in fields such as lithography, stereolithography, or 3D printing. [ABSTRACT FROM AUTHOR]

Patients with early Alzheimer's disease (AD) have difficulty in learning new information and in detecting novel stimuli. The underlying physiological mechanisms are not well known. We investigated the electrophysiological correlates of the early (< 400 ms), automatic phase of novelty detection and encoding in AD. We used high-density EEG Queryin patients with early AD and healthy age-matched controls who performed a continuous recognition task (CRT) involving new stimuli (New), thought to provoke novelty detection and encoding, which were then repeated up to 4 consecutive times to produce over-familiarity with the stimuli. Stimuli then reappeared after 9–15 intervening items (N-back) to be re-encoded. AD patients had substantial difficulty in detecting novel stimuli and recognizing repeated ones. Main evoked potential differences between repeated and new stimuli emerged at 180–260 ms: neural source estimations in controls revealed more extended MTL activation for N-back stimuli and anterior temporal lobe activations for New stimuli compared to highly familiar repetitions. In contrast, AD patients exhibited no activation differences between the three stimulus types. In direct comparison, healthy subjects had significantly stronger MTL activation in response to New and N-back stimuli than AD patients. These results point to abnormally weak early MTL activity as a correlate of deficient novelty detection and encoding in early AD. [ABSTRACT FROM AUTHOR]

In order to realize the multi-axis linkage machining of large slender integral structural parts，the new （（3-RPR+R） & UPS） + P hybrid machine tool mechanism with five degrees of freedom is proposed. The inverse kinematics model of the hybrid machine tool mechanism is established by using analytic vector method，and on this basis，the first-order and second-order kinematic influence coefficient matrices are obtained according to the kinematic influence coefficient method，and a more complete inverse kinematics model is established. Finally，the inverse kinematics model of the hybrid machine tool mechanism is solved by Matlab and simulated by Adams，and the results are basically consistent，which verifies the correctness of the inverse kinematics model of the hybrid machine tool mechanism.

Heat transport when two surfaces of solids come into contact is an important phenomenon in many metallurgical processes. Determining the boundary conditions of heat transfer allows to obtain the correct solutions of the heat conduction equation. The paper presents models for determining the heat transfer coefficient between steel materials in contact. Experimental tests were carried out to measure the temperature changes of the contacting samples made of steel S235 (1.0038) and steel 15HM (1.7335) under the pressure of 10, 15 and 20 MPa. There was a large temperature difference between the samples. The results of the experiment were compared with numerically calculated temperatures and the value of the heat transfer coefficient was determined at different pressure values depending on the time. [ABSTRACT FROM AUTHOR]

• Recent improvements in the design of magnetocardiographic measurement systems make it possible to implement small, relatively nonexpensive MCG scanners in ordinary, unshielded, medium-sized rooms directly inside clinical departments, • Magnetocardiographic examination in the real clinical situation is expected to answer the following fundamental questions: (1) Are chest pain and other related symptoms associated with heart pathology, i.e., cardiogenic? (2) If yes, how severe is this pathology? (3) If these symptoms are cardiogenic, are they associated only with coronary artery disease or other heart diseases? • Both visual evaluation of sets of CDV maps and automatic decision rules based on linear discriminant analysis are applied for assessing the degree of abnormality. • The pattern recognition method based on the k-nearest neighbor rule is applied for differential diagnosis of the MCG results. • The techniques are described for localizing the pathological changes in the myocardium based on three-dimensional visualization of the inverse problem solution. Magnetocardiography undoubtedly has exceptionally high sensitivity to electrophysiological changes in the myocardium. This is an absolutely non-invasivemethod with no contraindications. However, several barriers exist to the widespread adoption of this technique into clinical routine. One of the most important is the lack of a clear and consistent medical algorithm for interpreting magnetocardiographic data, leading to a clinically significant decision. The article outlines the main clinical questions clinicians pose using the magnetocardiography method. Methods for assessing the degree of abnormality of the results of a magnetocardiographic study and differential diagnosis based on the analysis of CDV maps are described in detail. Both methods for visual evaluation of sets of these maps and automatic decision rules based on linear discriminant analysis and pattern recognition are characterized. Also, techniques are described for localizing the pathological changes in the myocardium. As an example of using the developed system for interpreting magnetocardiographic data, the results of two multicenter studies in which this system of interpretation of MCG studies was used are presented. The magnetocardiographic examination is reliable for diagnosing chronic coronary heart disease, including in difficult-to-diagnose cases. A consistent system for interpreting of magnetocardiographic data allows medical practitioners to easily master the MCG technology and obtain the correct examination result. [ABSTRACT FROM AUTHOR]

We present expressions to compute the inverse of a Cauchy-type singular integral equation representing the relation between a double-peaked Coulomb stress in a fault or fracture and the resulting slip gradient in two distinct collinear slip patches. In particular we consider a situation where the patches are close enough to account for the influence of the slip gradient in one patch on the slip-induced shear stress in the other patch and vice versa. This situation can occur during depletion-induced or injection-induced fault slip in subsurface reservoirs for, e.g., natural gas production, hydrogen or CO 2 storage, or geothermal operations. The theory for a single slip patch is well-developed but the situation is less clear for a configuration with two patches although the monographs of Muskhelishvili (1953) and Weertman (1996) provide earlier results. We show that the general inverse solution for the coupled two-patch problem requires six auxiliary conditions to ensure six physical requirements: boundedness of the slip gradient at the four end points of the slip patches and vanishing of the integrals of the slip gradient over the patches. Mathematically, the presence of two additional conditions, as compared to earlier formulations, corresponds to two undetermined coefficients in the general solution of the governing integral equation. Numerical simulation confirms that at least one of these is always non-zero in the coupled situation. For a coupled double-patch case with a symmetric pre-slip Coulomb stress pattern, the general inverse solution requires three auxiliary conditions. Moreover the conditions for the asymmetric case may be reduced to a set of four again, but these are different from the sets of four obtained earlier by Muskhelishvili (1953) and Weertman (1996). We illustrate the theory with a numerical example in which the evaluation of the Cauchy integrals is performed with a modified version of augmented Gauss–Chebyshev quadrature that relies on analytical inversion. • We clarify the interaction between neighboring collinear slip patches in geological faults during induced fault slip in subsurface reservoirs. • We derive a physically consistent inverse solution of the singular integral equation that governs the slip gradient in two interacting patches. • We explain the origin of inconsistent results for slip with interacting patches as obtained from earlier published solutions. [ABSTRACT FROM AUTHOR]

Diffuse optical tomography (DOT) is promising to investigate functional and structural information in biological tissue by involving the forward problem and inverse solution. The work within this study develops an image reconstruction algorithm based on frequency-domain DOT using multi-frequency. In the forward problem, numerical simulation performs a diffusion equation to compute the light radiance distribution inside the model geometry with the assumed light intensity and optical properties. While in inverse solution, the absorption and reduced scattering coefficients are reconstructed utilizing light boundary data. To test the algorithm, several simulation cases, such as different contrast ratios between background and inclusion, inclusion size, as well as single and multi-frequency using one to three frequencies each and simultaneously are implemented. For verifying the image reconstruction results of multi-frequency, an objective numerical assessment, namely contrast and size detail is applied with a threshold value to specify the visible inclusion inside the geometry. Reconstructed images indicate that the effectivity of two frequencies in multi-frequency with 100 and 150 MHz has similar results as in single-frequency with 200 MHz. Therefore, the more number of frequencies may not enhance the contrast and image quality. [ABSTRACT FROM AUTHOR]

This study investigates a nonlinear model-based feature extraction approach for the accurate classification of four types of heartbeats. The features are the morphological parameters of ECG signal derived from the nonlinear ECG model using an optimization-based inverse problem solution. In the model-based methods, high feature extraction time is a crucial issue. In order to reduce the feature extraction time, a new structure was employed in the optimization algorithms. Using the proposed structure has considerably increased the speed of feature extraction. In the following, the effectiveness of two types of optimization methods (genetic algorithm and particle swarm optimization) and the McSharry ECG model has been studied and compared in terms of speed and accuracy of diagnosis. In the classification section, the adaptive neuro-fuzzy inference system and fuzzy c-mean clustering methods, along with the principal component analysis data reduction method, have been utilized. The obtained results reveal that using an adaptive neuro-fuzzy inference system with data obtained from particle swarm optimization will have the shortest process time and the best diagnosis, with a mean accuracy of 99% and a mean sensitivity of 99.11%. [ABSTRACT FROM AUTHOR]

To investigate the crustal structure of the Bitlis–Pötürge Suture Zone and its vicinity, gravity complete Bouguer anomaly data obtained from the World Gravity Map (WGM2012) were analyzed using Spectral Depth Estimation, Frequency Filtering, Total Horizontal Derivative (THD) and Parker-Oldenburg inversion techniques. The THD method was applied to the data after band-pass filtering of Bouguer gravity data in order to image the discontinuities in the basement levels which are determined by the critical wave numbers determined from the amplitude spectrum of gravity complete Bouguer anomaly data. The maximum amplitude values of the THD were used to reveal the discontinuities caused by the density difference in the BPSZ and its vicinity. In addition, the basement upper surface topography of the region was calculated and mapped with the inverse solution. The presence of an uplift area that is an antiroot in the south of the study area, as well as the subsidence that is a root of the BPSZ was determined. As a result of the inverse solution, it was determined that the depth of the sedimentary basement in the south approximately reaches 6 km and was detected the presence of approximately 7 km thick sedimentary deposit on the BPSZ. Basement upper surface depth is calculated as 8 km in average under the Eastern Anatolian High Plateau. [ABSTRACT FROM AUTHOR]

The pointing accuracy of the Risley prisms beam-steering system mainly depends on the accuracy of the solution method and the impact of the error on the solution. To improve pointing accuracy, the impact of systematic errors on the inverse solution precision is investigated and a correction method is proposed. First, a more accurate error model for Risley prisms is established, and the errors are obtained by the parameter identification method, which corrects the forward solution error. Second, we explain the reason for the error generated by the inverse solution and analyze the variation of the inverse solution error magnitude with the beam deflection angle. A correction method based on pointing-field transformation is proposed. Finally, simulations and experiments are performed to verify the feasibility of the method. Experimental results show that when the beam deflection angle is equal to 0.1°, the maximum and RMS values of the pointing error are reduced by 94.08% and 95.18%, respectively. [ABSTRACT FROM AUTHOR]

Emotion plays a significant role in perceiving external events or situations in daily life. Due to ease of use and relative accuracy, Electroencephalography (EEG)-based emotion recognition has become a hot topic in the affective computing field. However, scalp EEG is a mixed-signal and cannot directly indicate the exact information about active cortex sources of different emotions. In this paper, we analyze the significant differences of active source regions and frequency bands for pairs of emotions-based reconstructed EEG sources using sLORETA, and 26 Brodmann areas are selected as the regions of interest (ROI). And then, six kinds of time- and frequency-domain features from significant active regions and frequency bands are extracted to classify different emotions using support vector machines. Furthermore, we compare the classification performances of emotion features extracted from active source regions and EEG sensors. We have demonstrated that the features from selected source regions can improve the classification accuracy by extensive experiments on the DEAP and TYUT 2.0 EEG-based datasets.

In the present study, the three-parameter one-dimensional vertical infiltration equation recently proposed by Poulovassilis and Argyrokastritis is examined. The equation includes the saturated hydraulic conductivity (Ks), soil sorptivity (S), and an additional parameter c; it is valid for all infiltration times. The c parameter is a fitting parameter that depends on the type of porous medium. The equation is characterized by the incorporation of the exact contribution of the pressure head gradient to flow during the vertical infiltration process. The application of the equation in eight porous media showed that it approaches to the known two-parameter Green–Ampt infiltration equation for parameter c = 0.300, while it approaches to the two-parameter infiltration equation of Talsma–Parlange for c = 0.750, which are the two extreme limits of the cumulative infiltration of soils. The c parameter value of 0.500 can be representative of the infiltration behavior of many soils for non-ponded conditions, and consequently, the equation can be converted into a two-parameter one. The determination of Ks, S, and c using one-dimensional vertical infiltration data from eight soils was also investigated with the help of the Excel Solver application. The results showed that when all three parameters are considered as adjustment parameters, accurate predictions of S and Ks are not achieved, while if the parameter c is fixed at 0.500, the prediction of S and Ks is very satisfactory. Specifically, in the first case, the maximum relative error values were 33.29% and 39.53% for S and Ks, respectively, while for the second case, the corresponding values were 13.25% and 17.42%.

Using inverse modeling to determine soil hydraulic properties has become increasingly popular in the last few decades, enabling investigators to obtain more accurate estimates of soil hydraulic parameters compared to laboratory methods. A field experiment study was conducted to estimate the soil hydraulic parameters and investigate some scenarios during the optimization process using an inverse solution in HYDRUS-ID software to simulate the water flow in bare soil. Twelve scenarios were studied at four depths of the simulation domain and three simulation periods. Statistical indices were used to judge the optimization process accuracy for all scenarios. The results showed that the use of field experiments (internal drainage method) to determine soil hydraulic parameters via an inverse solution in HYDRUS software is rather easy, low-cost, and accurate enough for non-academic purposes, such as irrigation water management that does not require a high accuracy. However, the inverse solution method had a better performance than the ROSETTA method in terms of the soil hydraulic parameter estimation. The optimization period of 25 days at a soil depth of 1 m or so is appropriate to obtain a better accuracy of the estimated soil hydraulic parameters. [ABSTRACT FROM AUTHOR]

The medial temporal lobe (MTL) is crucial for memory encoding and recognition. The time course of these processes is unknown. The present study juxtaposed encoding and recognition in a single paradigm. Twenty healthy subjects performed a continuous recognition task as brain activity was monitored with a high-density electroencephalography. The task presented New pictures thought to evoke encoding. The stimuli were then repeated up to 4 consecutive times to produce over-familiarity. These repeated stimuli served as "baseline" for comparison with the other stimuli. Stimuli later reappeared after 9–15 intervening items, presumably associated with new encoding and recognition. Encoding-related differences in evoked response potential amplitudes and in spatiotemporal analysis were observed at 145–300 ms, whereby source estimation indicated MTL and orbitofrontal activity from 145 to 205 ms. Recognition-related activity evoked by late repetitions occurred at 405–470 ms, implicating the MTL and neocortical structures. These findings indicate that encoding of information is initiated before it is recognized. The result helps to explain modifications of memories over time, including false memories, confabulation, and consolidation. [ABSTRACT FROM AUTHOR]

To study the crustal structure of the Eastern Pontides, gravity data obtained from the World Gravity Map (WGM2012) were analyzed using total horizontal derivative (THD), Parker–Oldenburg (PO) inversion, and normalized full gradient (NFG) techniques. The THD method was applied to the data after bandpass filtering of the Bouguer gravity data in order to image the discontinuities in the basement levels. The maximum amplitude values of the THD were used to reveal the discontinuities caused by the density difference in the Eastern Pontides and its vicinity. In addition, the basement upper surface topography of the region was calculated and mapped with the inverse solution, and the presence of uplift areas in the Eastern Pontides was determined. As a result of the inverse solution, it was found that the depth of the basement in the Eastern Pontides belt reached approximately 5.5 km. An average basement upper surface depth of 3 km was calculated for the area under the Black Sea coastline. Finally, depth values were calculated using the NFG method under the determined profiles, and the depth values found by the inverse solution were tested. For the basement upper surface topography, the results obtained from the two depth calculations were found to be compatible, within error limits of ±0.2 km. [ABSTRACT FROM AUTHOR]

The medial temporal lobe (MTL) is crucial for memory encoding and recognition. The time course of these processes is unknown. The present study juxtaposed encoding and recognition in a single paradigm. Twenty healthy subjects performed a continuous recognition task as brain activity was monitored with a high-density electroencephalography. The task presented New pictures thought to evoke encoding. The stimuli were then repeated up to 4 consecutive times to produce over-familiarity. These repeated stimuli served as “baseline” for comparison with the other stimuli. Stimuli later reappeared after 9–15 intervening items, presumably associated with new encoding and recognition. Encoding-related differences in evoked response potential amplitudes and in spatiotemporal analysis were observed at 145–300 ms, whereby source estimation indicated MTL and orbitofrontal activity from 145 to 205 ms. Recognition-related activity evoked by late repetitions occurred at 405–470 ms, implicating the MTL and neocortical structures. These findings indicate that encoding of information is initiated before it is recognized. The result helps to explain modifications of memories over time, including false memories, confabulation, and consolidation.

Today, mechanical tracking systems are becoming increasingly compact, enabling a new range of civil and military applications. These include aerial laser scanning, for which Risley prisms are used. In Risley systems, the so-called inverse problem, which focuses on obtaining the angles of the prisms for a given target coordinate, has not yet been solved mathematically. As a consequence, approximate approaches have been used, but the solutions obtained have significant errors and a lack of precision. To improve accuracy, iterative methods, which are computationally intensive, have also been implemented. In this paper, an analytical process which we call the geometric method is presented, and we verified that this strategy highly improves accuracy and computational speed. Using this method in an iterative process gives accuracies of up to 1 pm in only three iterations. This high accuracy would allow the geometric method to be applied in fields such as lithography, stereolithography, or 3D printing.

To investigate the crustal structure of the Archangelsky Ridge, gravity data obtained from the World Gravity Map (WGM2012) were analyzed using Total Horizontal Derivative (THD), Parker-Oldenburg (PO) inversion and Normalized Full Gradient (NFG) techniques. The THD method was applied to the Bouguer gravity after band-pass filtering in order to image the discontinuities. The maximum amplitude values ​​of the THD were used to reveal the discontinuities caused by the density difference in the Archangelsky Ridge and its vicinity. In addition, the basement upper surface topography of the region was calculated and mapped with the inverse solution. Moreover, the presence of an uplift area in the northeast of the study area, as well as the elevation of the Archangelsky Ridge was determined. The depth to the Cretaceous aged sedimentary basement in the Sinop basin and on the Archangelsky Ridge approximately reaches 4 km and 1.6 km, respectively. The average upper surface depth of the basement is calculated as 5 km under the Eastern Black Sea Basin (EBSB). Finally, depth calculations were made using NFG method for the selected profiles and correlated with gravity inversion results. The depth results of the basement upper surface topography obtained from NFG and inversion methods are compatible with each other within ± 0.1 km error limits. [ABSTRACT FROM AUTHOR]

Electrocardiographic imaging (ECGI) is a technique to reconstruct non-invasively the electrical activity on the heart surface from body-surface potential recordings and geometric information of the torso and the heart. ECGI has shown scientific and clinical value when used to characterize and treat both atrial and ventricular arrhythmias. Regarding atrial fibrillation (AF), the characterization of the electrical propagation and the underlying substrate favoring AF is inherently more challenging than for ventricular arrhythmias, due to the progressive and heterogeneous nature of the disease and its manifestation, the small volume and wall thickness of the atria, and the relatively large role of microstructural abnormalities in AF. At the same time, ECGI has the advantage over other mapping technologies of allowing a global characterization of atrial electrical activity at every atrial beat and non-invasively. However, since ECGI is time-consuming and costly and the use of electrical mapping to guide AF ablation is still not fully established, the clinical value of ECGI for AF is still under assessment. Nonetheless, AF is known to be the manifestation of a complex interaction between electrical and structural abnormalities and therefore, true electro-anatomical-structural imaging may elucidate important key factors of AF development, progression, and treatment. Therefore, it is paramount to identify which clinical questions could be successfully addressed by ECGI when it comes to AF characterization and treatment, and which questions may be beyond its technical limitations. In this manuscript we review the questions that researchers have tried to address on the use of ECGI for AF characterization and treatment guidance (for example, localization of AF triggers and sustaining mechanisms), and we discuss the technological requirements and validation. We address experimental and clinical results, limitations, and future challenges for fruitful application of ECGI for AF understanding and management. We pay attention to existing techniques and clinical application, to computer models and (animal or human) experiments, to challenges of methodological and clinical validation. The overall objective of the study is to provide a consensus on valuable directions that ECGI research may take to provide future improvements in AF characterization and treatment guidance.

Electrocardiographic imaging (ECGI) is a technique to reconstruct non-invasively the electrical activity on the heart surface from body-surface potential recordings and geometric information of the torso and the heart. ECGI has shown scientific and clinical value when used to characterize and treat both atrial and ventricular arrhythmias. Regarding atrial fibrillation (AF), the characterization of the electrical propagation and the underlying substrate favoring AF is inherently more challenging than for ventricular arrhythmias, due to the progressive and heterogeneous nature of the disease and its manifestation, the small volume and wall thickness of the atria, and the relatively large role of microstructural abnormalities in AF. At the same time, ECGI has the advantage over other mapping technologies of allowing a global characterization of atrial electrical activity at every atrial beat and non-invasively. However, since ECGI is time-consuming and costly and the use of electrical mapping to guide AF ablation is still not fully established, the clinical value of ECGI for AF is still under assessment. Nonetheless, AF is known to be the manifestation of a complex interaction between electrical and structural abnormalities and therefore, true electro-anatomical-structural imaging may elucidate important key factors of AF development, progression, and treatment. Therefore, it is paramount to identify which clinical questions could be successfully addressed by ECGI when it comes to AF characterization and treatment, and which questions may be beyond its technical limitations. In this manuscript we review the questions that researchers have tried to address on the use of ECGI for AF characterization and treatment guidance (for example, localization of AF triggers and sustaining mechanisms), and we discuss the technological requirements and validation. We address experimental and clinical results, limitations, and future challenges for fruitful application of ECGI for AF understanding and management. We pay attention to existing techniques and clinical application, to computer models and (animal or human) experiments, to challenges of methodological and clinical validation. The overall objective of the study is to provide a consensus on valuable directions that ECGI research may take to provide future improvements in AF characterization and treatment guidance. [ABSTRACT FROM AUTHOR]

The kinetics of heat transfer in hardening concrete is a key issue in engineering practice for erecting massive concrete structures. Prediction of the temperature fields in early age concrete should allow for proper control of the construction process to minimize temperature gradients and the peak temperatures, which is of particular importance for concrete durability. The paper presents a method of identification of the thermophysical parameters of early age concrete such as the thermal conductivity, the specific heat, and the heat generated by cement hydration in time. Proper numerical models of transient heat conduction problems were formulated by means of finite-element method, including two types of heat losses. The developed experimental–numerical approach included the transient temperature measurements in an isolated tube device and an in-house implementation of an evolutionary algorithm to solve the parameter identification task. Parametric Bezier curves were proposed to model heat source function, which allowed for identifying such function as a smooth curve utilizing a small number of parameters. Numerical identification tasks were solved for experimental data acquired on hardening concrete mixes differing in the type of cement and type of mineral aggregate, demonstrating the effectiveness of the proposed method (the mean-squared error less than 1 °C). The proposed approach allows for the identification of thermophysical parameters of early age concrete even for mixtures containing non-standard components while omitting drawbacks typical for classical optimization methods. [ABSTRACT FROM AUTHOR]

The pointing accuracy of the Risley prisms beam-steering system mainly depends on the accuracy of the solution method and the impact of the error on the solution. To improve pointing accuracy, the impact of systematic errors on the inverse solution precision is investigated and a correction method is proposed. First, a more accurate error model for Risley prisms is established, and the errors are obtained by the parameter identification method, which corrects the forward solution error. Second, we explain the reason for the error generated by the inverse solution and analyze the variation of the inverse solution error magnitude with the beam deflection angle. A correction method based on pointing-field transformation is proposed. Finally, simulations and experiments are performed to verify the feasibility of the method. Experimental results show that when the beam deflection angle is equal to 0.1°, the maximum and RMS values of the pointing error are reduced by 94.08% and 95.18%, respectively.

Inverse modeling is a relatively complex procedure that allows quick estimation of soil hydraulic properties, yielding parameters for both soil water retention and unsaturated hydraulic conductivity function from a single experiment. The purpose of this research was to evaluate saline water effect on unsaturated hydraulic properties of clay loamy nonsaline-sodic soil layers and estimate these properties inversely from infiltration data using a double-ring infiltrometer.Three levels of water salinity (EC) 1.1, 2.2 and 5.8 dS/m were used for each treatment (T1, T2, and T3, respectively). Soil samples at three depths (0–20, 20–40 and 40–60 cm) were taken to measure Mualem–van Genuchten (MVG) hydraulic parameters (θr, residual water content, θs, saturated water content, α and n, shape parameters, and Ks, lab saturated hydraulic conductivity). Soil hydraulic parameters were estimated with an inverse solution using HYDRUS-1D model and infiltration data. Besides, the most sensitive MVG parameters to infiltration data (n, θs, and Ks) were inversely estimated due to difficulty in estimating several parameters simultaneously. Results showed that salinity had no significant effect on soil water infiltration and soil hydraulic conductivity changes in the specified salinity range according to the variance analyses (ANOVA).The Nash–Sutcliffe coefficient of efficiency (Ce) between simulated (HYDRUS) and measured values of cumulative infiltration data was about 0.998, indicating an excellent match. Soil water retention, as well as unsaturated soil hydraulic conductivity, were optimized with reasonable accuracy when the soil profile was assumed to be homogenous. In addition, simulated soil-water contents were quite similar to the measured values in which the values of Nash–Sutcliffe efficiency (Ce) for T1, T2, and T3 were 0.83, 0.85, and 0.85, respectively. In conclusion, the soil hydraulic parameters can be inversely estimated using the measured infiltration data through the double ring method if the soil is homogeneous. [ABSTRACT FROM AUTHOR]

This study proposes the use of artificial neural network (ANN) based surrogate framework along with simulated annealing (SA) approach to inversely estimate the optimum values of heat source control parameters in a heat treatment furnace. In particular, a two-dimensional radiant furnace with gas fired heaters has been considered and the heat source control parameters for a general gaussian heating profile are estimated to achieve better heat flux uniformity at the specimen. To expedite the forward radiative transfer calculations, ANN based surrogate is developed and coupled with SA. The maximum difference in radiative transfer solution and ANN is found to be less than 6%. Results indicate that the uniformity of fluxes is largely dependent on the emissivity of the specimen and its overall length, the dependence on specimen temperature and gas concentration is minimal. Cross validation of optimum heating profiles with radiative transfer solver shows an excellent match in local heat flux predictions. Overall, combined ANN-SA based algorithm proves to be an accurate and fast tool in heat source control parameter optimization problem. [ABSTRACT FROM AUTHOR]

Introduction: Electric source imaging (ESI) refers to the estimation of the cerebral sources of electric signals recorded at the head surface using electroencephalography (EEG). Thanks to the availability of EEG systems with high numbers of electrodes and to progress in software to analyze the signals they collect, ESI can be applied to epilepsy-related pathological EEG signals like interictal spikes and seizures. Areas covered: In this narrative review, we discuss selected original research articles on the use of ESI in epilepsy patients considered for surgery. Epilepsy-related activity can be localized accurately using ESI, as established by comparison to the gold standards of intracranial EEG and seizure control following epilepsy surgery. The information brought by ESI complements successfully that of other techniques like magnetic resonance imaging and positron-emission tomography, and is clinically relevant to patient management. Expert opinion: EEG is a readily available technique to measure brain activity in real time. Given its accuracy and usefulness, ESI should become part of the routine practice of clinical neurophysiology laboratories and epilepsy centers in the presurgical management of epilepsy patients. [ABSTRACT FROM AUTHOR]