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Carbon and other volatiles are transported from Earth’s surface into the mantle at subduction margins. The efficiency of this transfer has profound implications for the nature and scale of geochemical heterogeneities in Earth’s deep (mantle) and shallow (crustal) reservoirs, as well as Earth’s oxidation state. However, the proportion of volatiles released in the forearc and backarc are not well constrained compared to fluxes from the volcanic front. Here, we use helium and carbon isotope data from deeply sourced springs along two cross-arc transects to show that ~91% of carbon released from the slab/mantle beneath the Costa Rica forearc is sequestered within the crust by calcite deposition, and an additional ~3% is incorporated into biomass through microbial chemolithoautotrophy. We estimate that ~1.2 × 10(exp 8) to 1.3 × 10(exp 10) mol CO2/yr are released from the slab beneath the forearc, resulting in up to ~19% less carbon being transferred to Earth’s deep mantle than previously estimated.

Smart retail stores are becoming the fact of our lives. Several computer vision and sensor based systems are working together to achieve such a complex and automated operation. Besides, the retail sector already has several open and challenging problems which can be solved with the help of pattern recognition and computer vision methods. One important problem to be tackled is the planogram compliance control. In this study, we propose a novel method to solve it. The proposed method is based on object detection, planogram compliance control, and focused and iterative search steps. The object detection step is formed by local feature extraction and implicit shape model formation. The planogram compliance control step is formed by sequence alignment via the modified Needleman-Wunsch algorithm. The focused and iterative search step aims to improve the performance of the object detection and planogram compliance control steps. We tested all these steps on two different datasets. The results show that our proposed method achieves a 0.992 F1 score in object detection and a 0.935 F1 score in planogram compliance control. We further analyzed the strengths and weaknesses of the proposed method from different perspectives. We finally summarized possible extensions to our work.

Requirements to understand and forecast the behavior of complex macroeconomic interactions mandate the use of high-dimensional macroeconometric models. The Global Vector Autoregressive (GVAR) modeling technique is very popular among them and it allows researchers and policymakers to take into account both the complex interdependencies that exist between various economic entities and the global economy through the world’s trade and financial channels. However, determining the cross-section unit size while using this approach is not a trivial task. In order to address this issue, we suggest an objective procedure for the detection of the size of the cross-country aggregation in GVAR models. While doing so, we depart from the Akaike Information Criterion (AIC) and propose an analytical modification to it, mainly employing an ad hoc approach without violating Akaike’s main principles. To supplement the theoretical results, small sample performances of those procedures are studied in Monte Carlo experiments as well as implementing our approach on real data. The numerical results suggest that our ad hoc modification of AIC can be used to determine the structure of the cross-section unit dimension in GVAR models, allowing the researchers and policymakers to build parsimonious models.

The present study investigates the effects of external fields, including magnetic, electric, and non-resonant high-frequency intense laser fields, on the binding energies of the heavy hole excitons and the (hh1-e1) interband transitions from the ground state energy level of the heavy hole to the ground state energy level of the electron in GaAs / Al x Ga 1 - x As Gaussian type single quantum well. The study also considers the roles of the well width and the structure parameter. The results obtained show that the geometrical shape of the structure and the applied external fields are very effective tools on the excitonic binding and excitonic absorption spectra. From the results obtained, it was observed that the bandgap of semiconductor materials can be tuned by changing the structural parameters along with the applied external fields according to the purpose. This tunability enables the development of devices with optimized performance and new functionalities, thus driving innovation in various fields of technology.

Malaysia Airlines Flight 370, which was flying from Kuala Lumpur, Malaysia, to Beijing, China, lost communication with air traffic control shortly after take-off on March 8, 2014, and vanished. While the rest of the world awaited news of the missing plane and the 239 people on board, officials and experts began to look into the limited information available concerning the airliner’s real activities. The disappearance of a Malaysia Airline flight, carrying 239 passengers and crew, is one of the world’s biggest aviation mysteries. Despite all the efforts and evidence obtained so far, the crash site of Malaysia Airlines Flight MH370 could not be determined exactly. In this study, which we have done, the crash zone of the aircraft has been determined approximately by using the data in the previously prepared reports. In addition, the average ocean current speeds, directions and the parts of the debris of the aircraft were investigated on the satellite images, and the estimation of the area where the plane crashed was tried to be strengthened.

In this study, we considered the electronic and optical properties of quantum wells with the exponential and hyperbolic Rosen–Morse potentials under an applied magnetic field. Calculations are made within the framework of effective mass and parabolic band approximations. We have used the diagonalization method by choosing a wave function based on the trigonometric orthonormal function to find eigenvalues and eigenfunctions of the confined electron. Our results show that the magnetic field, asymmetry, and confinement parameters cause a significant increase in electron energies and energy differences between the electron states and the blue shift in the absorption peaks. These results can be used to probe materials’ electronic and structural properties and develop new materials with tailored optical properties.

In this paper, we investigate theoretically the effects of a spatially varying effective mass distribution on the electronic and optical properties of octic anharmonic oscillators. Calculations to determine eigenvalues and eigenfunctions of the electron are performed within the effective mass approximation by using the diagonalization method. Optical absorption coefficients are obtained from the two-level approach in the density matrix expansion. Numerical results show that the position-dependent effective mass has a significant effect on the electronic energies and transitions between the subbands in single and double octic anharmonic oscillators. Furthermore, it was found that the optical properties of the system can be tailored in accordance with the desired purpose by changing the structural parameters of the system determining the size and the shape and with a proper choice of effective mass distribution.

Galileo is Europe’s Global Navigation Satellite System (GNSS), which provides improved positioning and timing data with significant benefits for many European services and users. Galileo enables users to know their exact location with greater precision than other available systems. Access to the Galileo signal in the obstructed and unobstructed environment provides benefits and opportunities for work, thanks to the improved performance and accuracy. The use of a Galileo-enabled receiver increases the number of satellites in view significantly. When compared to the performance of single-constellation receivers, this significantly reduces the time required to obtain a position with centimetre-level accuracy. The results indicate the current Galileo constellation’s suitability for high-precision RTK applications, as well as improved availability, accuracy, reliability, and time-to-fix in the obstructed and unobstructed environments. The results of RTK GPS and RTK GPS/Galileo obtained at different times of the same day by using two reference points were compared. The results of this study illustrate that integrating RTK GPS system with Galileo is favorable for surveying applications (cm accuracy). This study shows that in surveying applications requiring centimetre accuracy, the RTK GPS/Galileo method can replace other survey methods (Total Station).

Smart retail stores started to take place in our lives. Several computer vision and sensor-based systems are working together to achieve such a complex and automated operation. Besides, the retail sector has several open and challenging problems which can be solved by embedded computer vision systems. One important problem to be tackled is shelf control or stock out detection. Here, shelves in a store should be controlled regularly such that no item is missing in the shelf. In this study, we propose an embedded computer vision system to solve this problem. To do so, we frame the shelf control operation as change detection. Due to the constraints posed by the retail sector, we formed the system by an ultra-low or low power microcontroller with an embedded camera attached to it. We provided all the implementation details of the system both from software and hardware perspectives. We also tested the proposed shelf control system from different perspectives. Hence, the reader can form such a system for retail sector or for a broad class of change detection problems in which stand-alone embedded system usage is mandatory.

Within the framework of effective mass theory, we investigate the effects of spin–orbit interaction (SOI) and Zeeman splitting on the electronic properties of an electron confined in GaAs single quantum rings. Energies and envelope wavefunctions in the system are determined by solving the Schrödinger equation via the finite element method. First, we consider an inversely quadratic model potential to describe electron confining profiles in a single quantum ring. The study also analyzes the influence of applied electric and magnetic fields. Solutions for eigenstates are then used to evaluate the linear inter-state light absorption coefficient through the corresponding resonant transition energies and electric dipole matrix moment elements, assuming circular polarization for the incident radiation. Results show that both SOI effects and Zeeman splitting reduce the absorption intensity for the considered transitions compared to the case when these interactions are absent. In addition, the magnitude and position of the resonant peaks have non-monotonic behavior with external magnetic fields. Secondly, we investigate the electronic and optical properties of the electron confined in the quantum ring with a topological defect in the structure; the results show that the crossings in the energy curves as a function of the magnetic field are eliminated, and, therefore, an improvement in transition energies occurs. In addition, the dipole matrix moments present a non-oscillatory behavior compared to the case when a topological defect is not considered.