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Background: Surgical procedures for proximal gastric cancer remain a highly debated topic. Total gastrectomy (TG) is widely accepted as a standard radical surgery. However, subtotal esophagectomy, proximal gastrectomy (PG) or even subtotal gastrectomy, when a small upper portion of the stomach can technically be preserved, are alternatives in current clinical practice. Methods: Using a cohort of the PGSAS NEXT trial, consisting of 1909 patients responding to a questionnaire sent to 70 institutions between July 2018 and December 2019, gastrectomy type, reconstruction method, and furthermore the remnant stomach size and the anti-reflux procedures for PG were evaluated. Results: TG was the procedure most commonly performed (63.0%), followed by PG (33.4%). Roux-en-Y was preferentially employed following TG irrespective of esophageal tumor invasion, while jejunal pouch was adopted in 8.5% of cases with an abdominal esophageal stump. Esophagogastrostomy was most commonly selected after PG, followed by the double-tract method. The former was preferentially employed for larger remnant stomachs (≧3/4), while being used slightly less often for tumors with as compared to those without esophageal invasion in cases with a remnant stomach 2/3 the size of the original stomach. Application of the double-tract method gradually increased as the remnant stomach size decreased. Anti-reflux procedures following esophagogastrostomy varied markedly. Conclusions: TG is the mainstream and PG remains an alternative in current Japanese clinical practice for proximal gastric cancer. Remnant stomach size and esophageal stump location appear to influence the choice of reconstruction method following PG.

As global warming intensifies, the damage caused by drought cannot be disregarded. Traditional drought monitoring is often carried out with monthly resolution, which fails to monitor the sub-monthly climatic event. The GRACE-based drought severity index (DSI) is a drought index based on terrestrial water storage anomalies (TWSA) observed by the gravity recovery and climate experiment (GRACE) satellite. DSI has the ability to monitor drought effectively, and it is in good consistency with other drought monitoring methods. However, the temporal resolution of DSI is limited by that of GRACE observations, so it is necessary to obtain TWSA with a higher temporal resolution to calculate DSI. We use a statistical method to reconstruct the TWSA, which adopts precipitation and temperature to obtain TWSA on a daily resolution. This statistical method needs to be combined with the time series decomposition method, and then the parameters are simulated by the Markov chain Monte Carlo (MCMC) procedure. In this study, we use this TWSA reconstruction method to obtain high-quality TWSA at daily time resolution. The correlation coefficient between CSR–TWSA and the reconstructed TWSA is 0.97, the Nash–Sutcliffe efficiency is 0.93, and the root mean square error is 16.57. The quality of the reconstructed daily TWSA is evaluated, and the DSI on a daily resolution is calculated to analyze the drought phenomenon in the Pearl River basin (PRB). The results show that the TWSA reconstructed by this method has high consistency with other daily publicly available TWSA products and TWSA provided by the Center for Space Research (CSR), which proves the feasibility of this method. The correlation between DSI based on reconstructed daily TWSA, SPI, and SPEI is greater than 0.65, which is feasible for drought monitoring. From 2003 to 2021, the DSI recorded six drought events in the PRB, and the recorded drought is more consistent with SPI-6 and SPEI-6. There was a drought event from 27 May 2011 to 12 October 2011, and this drought event had the lowest DSI minimum (minimum DSI = −1.76) recorded among the six drought events. The drought monitored by the DSI is in line with government announcements. This study provides a method to analyze drought events at a higher temporal resolution, and this method is also applicable in other areas. [ABSTRACT FROM AUTHOR]

Surgical procedures for proximal gastric cancer remain a highly debated topic. Total gastrectomy (TG) is widely accepted as a standard radical surgery. However, subtotal esophagectomy, proximal gastrectomy (PG) or even subtotal gastrectomy, when a small upper portion of the stomach can technically be preserved, are alternatives in current clinical practice. Using a cohort of the PGSAS NEXT trial, consisting of 1909 patients responding to a questionnaire sent to 70 institutions between July 2018 and December 2019, gastrectomy type, reconstruction method, and furthermore the remnant stomach size and the anti-reflux procedures for PG were evaluated. TG was the procedure most commonly performed (63.0%), followed by PG (33.4%). Roux-en-Y was preferentially employed following TG irrespective of esophageal tumor invasion, while jejunal pouch was adopted in 8.5% of cases with an abdominal esophageal stump. Esophagogastrostomy was most commonly selected after PG, followed by the double-tract method. The former was preferentially employed for larger remnant stomachs (≧3/4), while being used slightly less often for tumors with as compared to those without esophageal invasion in cases with a remnant stomach 2/3 the size of the original stomach. Application of the double-tract method gradually increased as the remnant stomach size decreased. Anti-reflux procedures following esophagogastrostomy varied markedly. TG is the mainstream and PG remains an alternative in current Japanese clinical practice for proximal gastric cancer. Remnant stomach size and esophageal stump location appear to influence the choice of reconstruction method following PG. [ABSTRACT FROM AUTHOR]

Recently, Proton Exchange Membrane Fuel Cell (PEMFC) with metal foam flow field has attracted extensive attention from scholars. In the present work, the full morphological reconstruction method of metal foam is improved and is successfully applied to a three-dimensional simulation of a metal foam PEMFC. The numerical predictions of metal foam PEMFC before and after reconstruction improvement are compared. The numerical results of the traditional channel flow field and two metal foam flow fields with pore sizes (40PPI and 100PPI) are compared. It is found that the application of metal foam can greatly improve the performance of PEMFC at higher current densities, and the smaller pore size (100PPI) of the metal foam makes the performance better. In addition, the numerical results of the oxygen concentration, ohmic loss, intra-membrane ionic current density and pressure drop of the cathode component are elaborated to explain the phenomenon. • 3D numerical simulation of flow field improvement for PEMFC. • Improved method for full morphological reconstruction of metal foam. • Build sufficient metal foam-GDL contact area. • Denser metal foam PEMFC offers better performance at high current densities. [ABSTRACT FROM AUTHOR]

Variations in graft arterial anatomy can increase the risk of postoperative hepatic arterial thrombosis (HAT), especially in presence of a replaced or accessory right hepatic artery (RHA). We retrospectively analyzed 223 cases of liver transplantations with the presence of an RHA on the graft. Patient outcomes were compared according to the four different reconstruction methods used: (i) the re‐implantation of the RHA into the splenic or gastroduodenal artery (n = 106); (ii) the interposition of the superior mesenteric artery (SMA) (n = 83); (iii) dual anastomosis (n = 24); (iv) use of an aortic patch including the origins of both the SMA and the coeliac trunk (n = 10). A competing risk analysis and Inverse Probability Weighting (IPW) were used. We found that the interposition of the SMA method was associated with a significantly lower incidence of HAT, at 4.8% compared to the re‐implantation method at 17.9%, dual anastomosis at 12.5%, and aortic patch at 20%, p =.03. In the competing risk analysis with IPW, the only risk factor for RHA thrombosis was the type of reconstruction. Taking the SMA interposition group as the reference, the sub‐hazard ratio (sHR) was 5.05 (CI 95 [1.72; 14.78], p <.01) for the re‐implantation group, sHR = 2.37 (CI 95 [0.51; 11.09], p =.27) for the dual anastomosis group and sHR = 2.24 (CI 95 [0.35; 14.33], p =.40) for the aortic patch group. There were no differences for intraoperative transfusion, hospitalization duration (p =.37) or incidence of severe complications (p =.1). The long‐term graft (p =.69) and patient (p =.52) survival was not different. In conclusion, the SMA interposition method was associated with a lower incidence of RHA thrombosis. [ABSTRACT FROM AUTHOR]

Catalyst utilization is an important determinant of proton exchange membrane fuel cell performance, and increasing the catalyst utilization is one of the most critical approaches to reducing the catalyst loading in PEMFC. 4-phase stochastic reconstruction method based on the variable-resolution Quartet Structure Generation Set (QSGS) algorithm is utilized to elucidate the influence of different parameters of electrode preparation, including the porosity, the dispersion degree of carbon agglomerate, ionomer content, and carbon support size, on the catalyst utilization in the catalyst layer. It was found that there exist optimal values for the porosity, dispersion degree of carbon agglomerate, ionomer content, and carbon support sizes in CLs and any deviations from these optimal values would lead to transport issues of electron, proton and mass within CLs. Taking electron, proton and mass transport into consideration simultaneously, the optimal Pt utilization is 46.55% among 48 cases in this investigation, taken at the carbon support diameter of 40 nm, the porosity of 0.4, the agglomerate spatial density of 25 μm−3 and I/C at 0.7. The selection of porosity, ultrasonic dispersion technique and ionomer content for conventional electrode preparation requires compromises on mass, electron and proton transport, leading to catalyst utilization in CLs hardly exceeding 50%. Therefore, the next generation of catalyst layer design and preparation technology is desired.

Introduction: This paper proposes a five-layer fully connected neural network for predicting radiation parameters in a radiation space based on detector readings.Methods: The network is trained and tested using gamma flux values from individual detector positions as input, and is used to predict the gamma radiation field in 3D space under different source term distributions. The method is evaluated using the mean percentage change error (PCT) for the test set under different source term distributions.Results: The results show that the neural network method can accurately predict radiation parameters with an average PCT error range of 0.53% to 3.11%, within the given measurement input error range of ± 10%. The method also demonstrates its ability to directly reconstruct the 3D radiation field with some simple source terms.Discussion: The proposed method has practical value in real operations within radiation spaces, and can be used to improve the accuracy and efficiency of predicting radiation parameters. Further research could explore the use of more complex source term distributions and the integration of other types of sensors for improved accuracy.

• A novel model combining variate-centric Transformer with large kernel temporal convolution was proposed. • Variate-centric Transformer was proposed to make self-attention acts on variables. • Large kernel temporal convolution was used to learn causal temporal information. • Experiments of microreactor process were conducted, which made algorithms be tested in real-world data. Fault detection and diagnosis (FDD) is an essential tool to ensure safety in chemical industries, and nowadays, many reconstruction-based deep learning methods are active in fault detection. However, many algorithms still suffer from not ideal actual performance. Inspired by the core mechanism of Transformer and large kernel convolution, this paper proposes a novel model combining variate-centric Transformer with large kernel temporal convolution. Variate-centric Transformer depends on self-attention to capture the multivariate correlations of input data, and large kernel temporal convolution collects period information to summarize temporal features. A benchmark dataset Tennessee Eastman process (TEP) and experiment data from the microreactor process are used to test the performance of fault detection. Compared with other reconstruction-based methods, results demonstrate that our model achieves a higher fault detection rate and a lower detection latency, and shows a significant potential for process safety. [ABSTRACT FROM AUTHOR]

To analyze the hazard-causing modes of landslides, this paper proposes a three-dimensional discrete element model reconstruction method that employs an unmanned aerial vehicle survey and multi-electrode resistivity tomography method. To convert the resistivity profile into a material profile, we adopt the peak of the probability density method for material classification and utilize the Haar wavelet transform for image denoising. Subsequently, inverse distance weighting interpolation and the curtain-point method are used to transform two-dimensional profiles into a 3D visualization model. Similarly, the triangular mesh boundary can be extracted from the 3D visualization model using the curtain-point method. A mapping function f including the macroscopic parameters, was defined to populate the particles within the boundaries. Using the iterative method and defining the loss function L for parameter calibration, the targeted 3D discrete element model was constructed after setting the velocity threshold. This method was applied to the Changhe landslide (September 14, 2019) in Gansu Province, China, which had a typical damaged soil layer due to earthquake and rainfall factors. The results indicate that the lower part first exhibits significant displacement, followed by the upper and middle parts, which is consistent with the on-site inspections and UAV findings. • Peak of probability density method for material threshold division of resistivity is proposed. • Using weak attribute inheritance method to define boundary particle attributes. • Given a complete modeling process for discrete elements. • Apply the method to practical applications and verify the results. [ABSTRACT FROM AUTHOR]

As global warming intensifies, the damage caused by drought cannot be disregarded. Traditional drought monitoring is often carried out with monthly resolution, which fails to monitor the sub-monthly climatic event. The GRACE-based drought severity index (DSI) is a drought index based on terrestrial water storage anomalies (TWSA) observed by the gravity recovery and climate experiment (GRACE) satellite. DSI has the ability to monitor drought effectively, and it is in good consistency with other drought monitoring methods. However, the temporal resolution of DSI is limited by that of GRACE observations, so it is necessary to obtain TWSA with a higher temporal resolution to calculate DSI. We use a statistical method to reconstruct the TWSA, which adopts precipitation and temperature to obtain TWSA on a daily resolution. This statistical method needs to be combined with the time series decomposition method, and then the parameters are simulated by the Markov chain Monte Carlo (MCMC) procedure. In this study, we use this TWSA reconstruction method to obtain high-quality TWSA at daily time resolution. The correlation coefficient between CSR–TWSA and the reconstructed TWSA is 0.97, the Nash–Sutcliffe efficiency is 0.93, and the root mean square error is 16.57. The quality of the reconstructed daily TWSA is evaluated, and the DSI on a daily resolution is calculated to analyze the drought phenomenon in the Pearl River basin (PRB). The results show that the TWSA reconstructed by this method has high consistency with other daily publicly available TWSA products and TWSA provided by the Center for Space Research (CSR), which proves the feasibility of this method. The correlation between DSI based on reconstructed daily TWSA, SPI, and SPEI is greater than 0.65, which is feasible for drought monitoring. From 2003 to 2021, the DSI recorded six drought events in the PRB, and the recorded drought is more consistent with SPI-6 and SPEI-6. There was a drought event from 27 May 2011 to 12 October 2011, and this drought event had the lowest DSI minimum (minimum DSI = −1.76) recorded among the six drought events. The drought monitored by the DSI is in line with government announcements. This study provides a method to analyze drought events at a higher temporal resolution, and this method is also applicable in other areas.

The brightness temperature reconstruction of synthetic aperture interferometric radiometers (SAIRs) is an underdetermined and ill-posed inverse problem. The classical Hilbert-space regularization methods have often the disadvantages of the oversmoothness effects and the oscillations. In this article, an adaptive Lp reconstruction method in Lebesgue spaces is introduced to obtain the accurate brightness temperature map in SAIRs. The proposed approach can adaptively adjust the exponent p between 1.2 and 2 according to the region of the map to be reconstructed. The experimental results show that the Lp reconstruction method can effectively reduce oversmoothness and Gibbs oscillations, and better improve the accuracy of the inverse results, compared to the traditional minimum-norm and band-limited regularization methods.

Objective. Fluorescence molecular tomography (FMT) is a promising non-invasive optical molecular imaging technology with strong specificity and sensitivity that has great potential for preclinical and clinical studies in tumor diagnosis, drug development and therapeutic evaluation. However, the strong scattering of photons and insufficient surface measurements make it very challenging to improve the quality of FMT image reconstruction and its practical application for early tumor detection. Therefore, continuous efforts have been made to explore more effective approaches or solutions in the pursuit of high-quality FMT reconstructions. Approach. This review takes a comprehensive overview of advances in imaging methodology for FMT, mainly focusing on two critical issues in FMT reconstructions: improving the accuracy of solving the forward physical model and mitigating the ill-posed nature of the inverse problem from a methodological point of view. More importantly, numerous impressive and practical strategies and methods for improving the quality of FMT reconstruction are summarized. Notably, deep learning methods are discussed in detail to illustrate their advantages in promoting the imaging performance of FMT thanks to large datasets, the emergence of optimized algorithms and the application of innovative networks. Main results. The results demonstrate that the imaging quality of FMT can be effectively promoted by improving the accuracy of optical parameter modeling, combined with prior knowledge, and reducing dimensionality. In addition, the traditional regularization-based methods and deep neural network-based methods, especially end-to-end deep networks, can enormously alleviate the ill-posedness of the inverse problem and improve the quality of FMT image reconstruction. Significance. This review aims to illustrate a variety of effective and practical methods for the reconstruction of FMT images that may benefit future research. Furthermore, it may provide some valuable research ideas and directions for FMT in the future, and could promote, to a certain extent, the development of FMT and other methods of optical tomography. [ABSTRACT FROM AUTHOR]

This paper presents the application of the edge reversal method for a further accurate evaluation of the three-dimensional tool geometry of a single-point diamond tool with an atomic force microscope (AFM). In the edge reversal method, the tip radius of an AFM probe, which ranges from a few nm to several-ten nm, can be evaluated quantitatively by using measured AFM profile data of a tool cutting edge and an indentation mark generated by the tool cutting edge. The AFM tip radius obtained by the edge reversal method is utilized in this paper to reconstruct the three-dimensional profile of the cutting edge of a single-point diamond tool from the AFM data, which is obtained in measurement as the convolution of the tool edge profile and the shape of AFM tool tip. The validity of the obtained AFM tip radius in the edge reversal method is verified by employing it for the compensation of the AFM image of a two-dimensional (2D) grating artifact. Finally, the reconstruction of the three-dimensional profile of the cutting edge of a single-point diamond tool is carried out, and the cutting edge radius and the nose radius of the tool are evaluated quantitatively based on the reconstructed three-dimensional (3D) profile of the cutting tool. [ABSTRACT FROM AUTHOR]

Abstract Proximal gastrectomy (PG) is one of the function‐preserving surgical methods for the treatment of upper gastric cancer. Favorable postoperative results have been reported in comparison with total gastrectomy. However, because there are challenges, such as postoperative reflux esophagitis, anastomotic stenosis, and residual food, appropriate selection of a reconstruction method is crucial. Some methods include esophagogastric anastomosis, including simple esophagogastrostomy, tube‐like stomach esophagogastrostomy, side overlap with fundoplication by Yamashita, and double‐flap technique, and reconstruction using the small intestine, including double‐tract methods, jejunal interposition, and jejunal pouch interposition. However, standard reconstruction methods are yet to be established. PG has also been employed in early gastric cancer of the upper third of the stomach, and indications have also been extended to esophagogastric junction cancer, which has shown an increase in recent years. Although many retrospective studies have revealed the functional benefits or oncological safety of PG, the characteristics of each surgical procedure should be understood so that an appropriate reconstruction method, with a reflux prevention mechanism and minimal postoperative injury, can be selected.

A reconstruction algorithm for flame 3D temperature distribution based on deep leaning and light field imaging was proposed. The deep feature of flame light field image was extracted by the convolutional neural network, and then the mapping between light field imaging and 3D temperature field is established to achieve the rapid reconstruction of flame 3D temperature distribution. Through the data set of flame light field image and 3D temperature distribution obtained by line-of-sight, the convolutional neural network was trained, and the test set was used to verify and evaluate the training results. The reconstruction results by the convolutional neural network algorithm and the traditional non-negative last squares (NNLS) algorithm were compared. The results show that the flame 3D temperature distribution reconstruction algorithm based on deep leaning and light field imaging can accurately reconstruct the flame temperature distribution with the average relative error of 0.14% and has high computational efficiency(when the flame grid is 10 x8 x15, the reconstruction time by NNLS algorithm is 4 759 s, and that by the deep leaning algorithm is 830 ^s). Also, the proposed algorithm is robust to image noise. [ABSTRACT FROM AUTHOR]

As a mesoscale phenomenon of the ocean, the ocean front can directly affect the structural characteristics of sound speed profiles and further affect the acoustic propagation characteristics of the sea area. In this paper, we use the fuzzy C-means (FCM) algorithm to cluster the surface sound speed in the sea area of the Kuroshio Extension (KE) and detect the frontal zone of Kuroshio Extension (KEF). At the same time, the sound speed profile (SSP) is used instead of the temperature profile to establish the model of the sound speed field in the front area of the Kuroshio Extension and to improve the theoretical model of the ocean front. Compared with the actual ocean front calculated by reanalysis data, the root means square error (RSME) of the transmission loss (TL) calculated by the model is controlled below 6 dB, which proves the validity of the model. Finally, we propose the melt function in the model to forecast the depth change of the acoustic convergence area. Compared with the actual calculation result based on reanalysis data, the root means square error (RSME) of the depth forecasting after the frontal zone is 43.3 m. This reconstruction method does not rely on the high spatial resolution data of the whole sea depth and can be of referential significance to acoustic detection in the ocean front environment. [ABSTRACT FROM AUTHOR]

Safety assessments of conventional coal mining under aquifers mainly use the height of the water-conducting zone (HWCZ) above the mining panel as the empirical safety criterion. However, this criterion alone fails to account for mining-induced permeability and porosity variations of key aquiclude strata (KAS) in backfill mining. Backfilling can compact and close developed fractures in the KAS, making it less permeable. In this paper, based on an analysis of KAS's regional geological and hydrogeological patterns, new concepts and methods of KAS reconstruction by backfill mining technology are introduced to provide safe mining of coal resources and protect water resources. The nature, reconstruction techniques, primary mode, and principle of KAS reconstruction by backfill mining are discussed in detail. The coupling deformation mechanism of single KAS and composite layered KAS in backfill mining are theoretically analyzed and numerically simulated. The results will aid theoretical analysis of safe coal mining design and water protection under surface water bodies and aquifers. [ABSTRACT FROM AUTHOR]

We identify two issues with the reverse regression approach as implemented in several classic reconstructions of past climate fluctuations from dendroclimatologcical data series. First, instead of estimating the causal relationship between the proxy, which is measured with significant error, as function of climate and formally inverting the relationship, most papers estimate the inverted relationship directly. This leads to biased coefficients and reconstructions with artificially low variance. Second, we show that inversion of the relationship is often done incorrectly when the underlying causal relationship is dynamic in nature. We show analytically as well as using Monte Carlo experiments and actual tree ring data, that the reverse regression method results in biased coefficients, reconstructions with artificially low variance and overly smooth reconstructions. We further demonstrate that correct application of the inverse regression method is preferred. However, if the measurement error in the tree ring index is significant, neither method provides reliable reconstructions.

Ion-exchange, reconstruction, and coprecipitation approaches were used to examine the composite formation of layered double hydroxides (LDHs) and glycyrrhizic acid. The use of reconstruction and coprecipitation approaches successfully intercalated the glycyrrhizic acid dipotassium salt into the LDH interlayer space, which enhanced moisturization. Furthermore, the uptake of glycyrrhizic acid in the composite synthesized using the coprecipitation approach was higher than that of the composite by the reconstruction approach. Additionally, the moisture content of the coprecipitated composite to skin was found to be higher than that of the pristine glycyrrhizic acid dipotassium salt, thereby strongly demonstrating the advantages of using LDHs for the generation of composites with higher moisture content. [ABSTRACT FROM AUTHOR]

Accurately reconstructing cropland cover in topographically complex areas has long been challenging for historical anthropogenic land cover change (ALCC) datasets. Sichuan Province, one of the most topographically complex areas in China, was chosen as a case study. This study integrated historical gazetteers and modern cropland statistics and survey data to examine and correct the prefecture-level cropland area of Sichuan Province. Subsequently, a novel cropland reconstruction model was proposed based on the order of cropland reclamation. Using this model, cropland changes in Sichuan Province from 1671 to 2019 were reconstructed with a spatial resolution of 5′ × 5′. The main findings were as follows: (1) The cropland reconstruction model designed in this study can well reproduce with the cropland cover in Sichuan Province. Compared with the prevailing ALCC datasets, our reconstructions were more consistent with descriptions of cropland changes in Sichuan Province in the literature. (2) The cropland cover in Sichuan Province expanded from northeastern and southern Sichuan to the Chengdu Plain and the hills north of the Yangtze River and then to the mountainous areas in the center and periphery of the basin from 1671 to 1985, after which it shrank in mountainous and urban areas. (3) The changes in cropland cover in Sichuan Province over the past 350 years were shaped by multiple factors such as war, famine, migration, agricultural policies and urbanization. The reconstructions in this study captured the spatial differences in cropland distribution in Sichuan Province, but their accuracy was limited by the cropland estimation method and the satellite-based cropland data used in the reconstruction model. • A new cropland reconstruction model based on the order of cropland reclamation was designed. • The 5′ × 5′ cropland cover change in Sichuan province over the past 350 years was reconstructed. • The cropland cover in Sichuan Province changed dramatically over the past 350 years. • Obvious differences in cropland cover from other datasets were observed in our reconstructions. • Our reconstructions were consistent with literature-based descriptions of agricultural reclamation in Sichuan Province. [ABSTRACT FROM AUTHOR]

Fatigue cracking in welded joints is a critical problem in bridge engineering, especially for aging long-span steel bridges. The crack size and density are increasing gradually with the bridge aging process, where the crack interaction will accelerate the crack propagation or even short cracks merging into a long crack. However, the mechanism underlying the coupled propagation behavior of multiple cracks remains unclear. In this study, the coupling effect of multiple cracks was investigated based on numerical simulations. Subsequently, the numerical result was verified by a full-scale segmental fatigue experiment. In order to overcome the time-consuming iterative computations, the back propagation (BP) neural network was utilized to predict the effective coupling spacing between multiple cracks. Finally, a new crack reconstruction method was proposed to simplify crack merging processes. Results indicate that the coupled propagation behavior is significantly impacted by the effective crack spacing. The coupling effect is more significant at the near-end point compared to other feature points. In addition, the cracks with similar sizes have greater coupled effect, which is the worst-case scenario for the multiple fatigue crack problem. The experimental study demonstrates that the growth rate of the near-end point is 1.53 times that of the far-end point and pre-made cracks merge together successfully. By utilizing the BP neural network, the relative error of predicted effective spacing of two cracks is 3.52%. Compared to existing design specifications, the new reconstruction method provides a more reliable result for the fatigue life prediction of the welding seam with multiple fatigue cracks. • Sensitive parameters for multiple crack coupling effects were investigated. • The coupling effect has a significant effect on the near-end point of the crack. • The coupling effect and effective spacing increase with crack shape ratio and size. • A crack reconstruction method is proposed based on the BP neural network. [ABSTRACT FROM AUTHOR]

The developed and tested methods of dynamic control of micro-objects (MOs) of nuclear fuel, based on the reconstruction of spatial geometric characteristics of MOs along the contours of two-dimensional shadow projections, are considered. To describe the dimensions of the MOs, the overall dimensions and the average projected diameter are chosen, and their shape is described using the nonsphericity coefficient, which is defined as the ratio of the maximum overall size of the object to its minimum overall size. Metrological characteristics of control methods are given. [ABSTRACT FROM AUTHOR]

Among many parameters characterizing atmospheric aerosols, aerosol mass extinction efficiency (MEE) is important for understanding the optical properties of aerosols. MEE is expressed as a function of the refractive indices (i.e., composition) and size distributions of aerosol particles. Aerosol MEE is often considered as a size-independent constant that depends only on the chemical composition of aerosol particles. The famous Malm's reconstruction equation and subsequent revised methods express the extinction coefficient as a function of aerosol mass concentration and MEE. However, the used constant MEE does not take into account the effect of the size distribution of polydispersed chemical composition. Thus, a simplified expression of size-dependent MEE is required for accurate and conventional calculations of the aerosol extinction coefficient and also other optical properties. In this study, a simple parameterization of MEE of polydispersed aerosol particles was developed. The geometric volume–mean diameters of up to 10 µm with lognormal size distributions and varying geometric standard deviations were used to represent the sizes of various aerosol particles (i.e., ammonium sulfate and nitrate, elemental carbon, and sea salt). Integrating representations of separate small mode and large mode particles using a harmonic mean-type approximation generated the flexible and convenient parameterizations of MEE that can be readily used to process in situ observations and adopted in large-scale numerical models. The calculated MEE and the simple forcing efficiency using the method developed in this study showed high correlations with those calculated using the Mie theory without losing accuracy. [ABSTRACT FROM AUTHOR]

Driven by sintering kinetics, stochastically distributed voids exist inevitably in nano‑silver sintered joints to affect their electrical, mechanical and thermal properties, reliability, etc. In this paper, a holistic approach including both void morphology characterization and reconstruction stages is developed for the reconstruction of Stochastically Distributed Void Morphologies (SDVMs) in nano‑silver sintered joints. A set of dispersion parameters, including area A, distance l, angle α, and aspect ratio δ, are firstly proposed for quantitatively characterizing the voids dispersion features of the SDVMs. Then on the basis of the characterization results, a reconstruction approach is developed based on the random medium theory and similarity comparison algorithm. The applicability and validity of the proposed voids dispersion characterization and SDVM reconstruction methods are verified through numerical and experimental case studies, respectively. And effects on the dispersion features of the SDVMs by such as autocorrelation function parameters and the sintering pressure are also investigated via the comparative discussions on the cumulative distribution function (cdf) curves of all dispersion parameters.

Proximal gastrectomy (PG) is one of the function‐preserving surgical methods for the treatment of upper gastric cancer. Favorable postoperative results have been reported in comparison with total gastrectomy. However, because there are challenges, such as postoperative reflux esophagitis, anastomotic stenosis, and residual food, appropriate selection of a reconstruction method is crucial. Some methods include esophagogastric anastomosis, including simple esophagogastrostomy, tube‐like stomach esophagogastrostomy, side overlap with fundoplication by Yamashita, and double‐flap technique, and reconstruction using the small intestine, including double‐tract methods, jejunal interposition, and jejunal pouch interposition. However, standard reconstruction methods are yet to be established. PG has also been employed in early gastric cancer of the upper third of the stomach, and indications have also been extended to esophagogastric junction cancer, which has shown an increase in recent years. Although many retrospective studies have revealed the functional benefits or oncological safety of PG, the characteristics of each surgical procedure should be understood so that an appropriate reconstruction method, with a reflux prevention mechanism and minimal postoperative injury, can be selected. [ABSTRACT FROM AUTHOR]

Hadamard coding spectral imaging technology is a computational spectral imaging technology, which modulates the target's spectral information and recovers the original spectrum by inverse transformation. Because it has the advantage of multichannel detection, it is being studied by more researchers. For the engineering realization of push-broom coding spectral imaging instrument, it will inevitably be subjected to push-broom error, template error and detection noise, the redundant sampling problem caused by detector. Therefore, three restoration methods are presented in this paper: firstly, the one is the least squares solution, the two is the zero-filling inverse solution by extending the coding matrix in the redundant coding state to a complete higher order Hadamard matrix, the three is sparse method. Secondly, the numerical and principle analysis shows that the inverse solution of zero-compensation has better robustness and is more suitable for engineering application; its conditional number, error expectation and covariance are better and more stable because it directly uses Hadamard matrix, which has good generalized orthogonality. Then, a real-time spectral reconstruction method is presented, which is based on inverse solution of zero-compensation. Finally, simulation analysis shows that spectral data could be destructed relative accuracy in the error condition; however, the effect of template noise and push error on reconstruction is much greater than that of detection error. Therefore, in addition to reducing the detection noise as much as possible, lower template noise and more accurate push controlling should be guaranteed specifically in engineering realization. [ABSTRACT FROM AUTHOR]

In this study, a tomography reconstruction problem of binary images is considered on the isometric grid. On this grid, the triangle pixels have two types of orientations, accordingly, the authors call them delta or nabla shape pixels. The proposed reconstruction method uses data of projections of three natural directions. They are the lane directions of the triangular tessellation (these directions are somewhat analogous to row/column directions on the rectangular grids). The projection ray, penetrating through a grid lane, now not passing through the middle of pixels (i.e. through the middle line of triangle shape pixels), as usually taken, but little bit shifted from the middle parallel to the lane. This method provides the exact information about the number of nabla and delta shape triangle pixels in each lane of the image. This additional information is included in the reconstruction process to improve the quality of reconstruction. They formulate the suggested model into an energy‐minimisation problem and apply a gradient‐based approach for its minimisation. They show and analyse various experimental results on test images. The presented approach shows both better quality reconstructions and shorter running time than the earlier approaches. [ABSTRACT FROM AUTHOR]

Local magnetic structures in space environments, in particular, those in the diffusion region such as magnetic nulls or separators, are very difficult to identify by satellite measurements but important for understanding of magnetic reconnection. Multi‐spacecraft missions such as Cluster or MMS, however, provide an opportunity to reconstruct the fine structures using vector data of space magnetometers. In this paper, we introduce a method for such a local reconstruction, based on the modified radial basis functions (Andreeva & Tsyganenko, 2016, https://doi.org/10.1002/2016JA023217), used previously for the global magnetic field modeling. A principal advantage of this method is its freedom from a priori assumptions on the magnetic field topology. The method has been tested on 21/2 and 3D reconnection geometries and provided a good agreement with preset models. The relative errors of null positions, γ‐line directions, and ∑‐surface normal directions are found to be below 6% even with 20% random errors added to the target magnetic field vectors in reconstruction of 3D separator model geometry. Applications of the method to the field reconstruction based on Cluster measurements are also presented and discussed. Key Points: A new method based on radial basis function expanding is developed to reconstruct magnetic structures utilizing multi‐spacecraft dataWithout prior imposed current sheet, the method can reconstruct the separator reconnection geometry comprised of two opposite polarity nulls [ABSTRACT FROM AUTHOR]

As a mesoscale phenomenon of the ocean, the ocean front can directly affect the structural characteristics of sound speed profiles and further affect the acoustic propagation characteristics of the sea area. In this paper, we use the fuzzy C-means (FCM) algorithm to cluster the surface sound speed in the sea area of the Kuroshio Extension (KE) and detect the frontal zone of Kuroshio Extension (KEF). At the same time, the sound speed profile (SSP) is used instead of the temperature profile to establish the model of the sound speed field in the front area of the Kuroshio Extension and to improve the theoretical model of the ocean front. Compared with the actual ocean front calculated by reanalysis data, the root means square error (RSME) of the transmission loss (TL) calculated by the model is controlled below 6 dB, which proves the validity of the model. Finally, we propose the melt function in the model to forecast the depth change of the acoustic convergence area. Compared with the actual calculation result based on reanalysis data, the root means square error (RSME) of the depth forecasting after the frontal zone is 43.3 m. This reconstruction method does not rely on the high spatial resolution data of the whole sea depth and can be of referential significance to acoustic detection in the ocean front environment.

Polyamide 6 (PA6) is able to absorb water from the surrounding air and bond to it by forming hydrogen bonds between the carbonamide groups of its molecular chains. Diffusion processes cause locally different water concentrations in the (component) cross-section during the sorption process, resulting in locally different mechanical properties due to the water-induced plasticisation effect. However, the water content of PA6 is usually specified as an integral value, so no information about a local water distribution within a component is provided. This paper shows a method to characterise moisture distributions within PA6 samples using low-energy computer tomography (CT) techniques and comparing the reconstructed results with a developed finite elements (FE) modelling method based on Fick’s diffusion laws with concentration-dependent diffusion coefficients. For this purpose, the ageing of the samples at two different water bath temperatures as well as at different integral water contents are considered. The results obtained by CT reconstruction and FE modelling are in very good agreement, so that the concentration distributions by water sorption of PA6 calculated by FEM can be regarded as validated.

Ultrasound computed tomography (USCT) systems based on capacitive micromachined ultrasonic transducer (CMUT) arrays have a wide range of application prospects. For this paper, a high-precision image reconstruction method based on the propagation path of ultrasound in breast tissue are designed for the CMUT ring array; that is, time-reversal algorithms and FBP algorithms are respectively used to reconstruct sound speed distribution and acoustic attenuation distribution. The feasibility of this reconstruction method is verified by numerical simulation and breast model experiments. According to reconstruction results, sound speed distribution reconstruction deviation can be reduced by 53.15% through a time-reversal algorithm based on wave propagation theory. The attenuation coefficient distribution reconstruction deviation can be reduced by 61.53% through FBP based on ray propagation theory. The research results in this paper will provide key technological support for a new generation of ultrasound computed tomography systems.

This paper presents a systematic structure and a control strategy for the electric vehicle charging station. The system uses a three-phase three-level neutral point clamped (NPC) rectifier to drive multiple three-phase three-level NPC converters to provide electric energy for electric vehicles. This topology can realize the single-phase AC mode, three-phase AC mode, and DC mode by adding some switches to meet different charging requirements. In the case of multiple electric vehicles charging simultaneously, a system optimization control algorithm is adopted to minimize DC-bus current fluctuation by analyzing and reconstructing the DC-bus current in various charging modes. This algorithm uses the genetic algorithm (ga) as the core of computing and reduces the number of change parameter variables within a limited range. The DC-bus current fluctuation is still minimal. The charging station system structure and the proposed system-level optimization control algorithm can improve the DC-side current stability through model calculation and simulation verification.

When mining coal below aquifers, the height of the water-conducting zone above the mine panel is widely used as one of the main criteria in assessing mine safety. However, its direct application to backfill mining is quite problematic, and alternative approaches have to be used to more accurately reflect the relevant processes. The compaction characteristics and seepage behavior in crushed key aquiclude strata were experimentally investigated by analyzing the hydrogeological characters of aquiclude strata and aquifers in the Wugou coal mine. The results explained the mechanism of the backfill mining-induced seepage and indicated the feasibility of reconstructing the key aquiclude strata to protect regional water resources. Based on the regional geology and hydrogeological characteristics of the aquiclude strata, various reconstruction forms were analyzed, with the approbation of structural and seepage stability criteria of aquiclude strata. The research results were corroborated by field measurements and provide new theoretical guidance for protecting water resources during mining in China. [ABSTRACT FROM AUTHOR]

• Propose a methodology to reconstruct structured clays like its natural intact clays. • The developed method is based on natural structural process of marine clays. • Applicability of method is verified by macro and micro evaluation. Quantitative laboratory studies on the structural behavior of natural intact marine clays require a large number of identical natural samples leading to an expensive and challenging task. This study proposes a simple method to reconstruct an artificial structured marine clay as the state of its natural intact clay at both macro and micro levels. For this purpose, the Shanghai marine clay is selected and mixed with low cement contents (1–6%). The clay-cement slurry is mixed in a container with the ice-covered sides at a low temperature about 0 ± 2 °C to postpone the hydration reactions until consolidation began. The purpose of adding cement is to generate the inter-particle bonding and structure in reconstituted samples. Initially, the reconstituted samples are consolidated under the in situ stress of 98 kPa and then under the pre-consolidation pressure of 50 kPa. Mechanical characteristics such as compression index, yield stress, unconfined compression strength, shear strength ratio, and the stress paths from triaxial tests are compared with natural intact clay accordingly. Scanning electron microscope and mercury intrusion porosimetry analyses are also performed to analyze the microstructure of clays for comparison. Furthermore, the proposed method is also examined by using natural intact marine clays of different locations and characteristics. [ABSTRACT FROM AUTHOR]

This paper proposed a new reconstruction method for the reconstruction of the support of the CCS water tunnel in Ecuador. This method avoided the traditional method of adding maintenance gates, reduced the construction difficulty and engineering investment and shortened the schedule. During the maintenance support tunnel could not only retain water during the operation period, but also repair the main tunnel of water conveyance tunnel under the condition that the main tunnel of the water conveyance tunnel was emptied during the maintenance period, and could also serve as a ventilation tunnel for the open water tunnel. The finite unstructured calculation was used for analysis and research, and a set of maintenance channel structure design method was explored, which finally formed a complete set of new methods for reconstruction and repair of the support tunnel. [ABSTRACT FROM AUTHOR]

In this paper, a noniterative reconstruction method for solving the inverse potential problem is proposed. The forward problem is governed by a modified Helmholtz equation. The inverse problem consists in the reconstruction of a set of anomalies embedded into a geometrical domain from partial or total boundary measurements of the associated potential. Since the inverse problem is written in the form of an ill‐posed boundary value problem, the idea is to rewrite it as a topology optimization problem. In particular, a shape functional measuring the misfit between the solution obtained from the model and the data taken from the boundary measurements is minimized with respect to a set of ball‐shaped anomalies by using the concept of topological derivatives. It means that the shape functional is expanded asymptotically and then truncated up to the desired order term. The resulting truncated expansion is trivially minimized with respect to the parameters under consideration that leads to a noniterative second order reconstruction algorithm. As a result, the reconstruction process becomes very robust with respect to the noisy data and independent of any initial guess. Finally, some numerical experiments are presented showing the capability of the proposed method in reconstructing multiple anomalies of different sizes and shapes by taking into account complete or partial boundary measurements. [ABSTRACT FROM AUTHOR]

We present in this paper a novel numerical reconstruction method for solving a three-dimensional inverse scattering problem with scattering data generated by a single direction of the incident plane wave. This problem is well known to be a highly nonlinear and ill-posed problem. Therefore, optimization-based reconstruction methods for solving this problem would typically suffer from the local-minima trapping and require strong a priori information of the solution. To avoid these problems, in our numerical method, we aim to construct a cost functional with a globally strictly convex property, whose minimizer can provide a good approximation for the exact solution of the inverse problem. The key ingredients for the construction of such a functional are an integro-differential formulation of the inverse problem and a Carleman weight function. Under a (partial) finite difference approximation, the global strict convexity is proven using the tool of Carleman estimates. The global convergence of the gradient projection method to the exact solution is proven as well. We demonstrate the efficiency of our reconstruction method via a numerical study of experimental backscatter data for buried objects. [ABSTRACT FROM AUTHOR]

We present a reconstruction method for solving a 3D coefficient inverse problem with a single measurement of phaseless scattering data. These are multifrequency data generated by a single direction of the incident plane wave. Our method consists of two stages, each of which is challenging in its own right. The first stage is the problem of the reconstruction of the wave field itself on the measurement plane from the measured intensity. In this stage, we prove a uniqueness result and study a numerical method for this reconstruction. After obtaining the approximate scattered field on the measurement plane, in the second stage, we exploit our newly developed globally convergent numerical method to solve the coefficient inverse problem with the phased scattering data. Our twostage method does not require any advanced information about the true solution of the phaseless coefficient inverse problem. Numerical examples are presented to demonstrate the performance of the method. [ABSTRACT FROM AUTHOR]

Synthetic aperture imaging radiometers (SAIRs) are powerful passive microwave systems for high-resolution imaging by use of synthetic aperture technique. However, the ill-posed inverse problem for SAIRs makes it difficult to reconstruct the high-precision brightness temperature map. The traditional regularization methods add a unique penalty to all the frequency bands of the solution, which may cause the reconstructed result to be too smooth to retain certain features of the original brightness temperature map such as the edge information. In this paper, a multi-parameter regularization method is proposed to reconstruct SAIR brightness temperature distribution. Different from classical single-parameter regularization, the multi-parameter regularization adds multiple different penalties which can exhibit multi-scale characteristics of the original distribution. Multiple regularization parameters are selected by use of the simplified multi-dimensional generalized cross-validation method. The experimental results show that, compared with the conventional total variation, Tikhonov, and band-limited regularization methods, the multi-parameter regularization method can retain more detailed information and better improve the accuracy of the reconstructed brightness temperature distribution, and exhibit superior noise suppression, demonstrating the effectiveness and the robustness of the proposed method.

Among many parameters characterizing atmospheric aerosols, aerosol mass extinction efficiency (MEE) is important for understanding the optical properties of aerosols. MEE is expressed as a function of the refractive indices (i.e., composition) and size distributions of aerosol particles. Aerosol MEE is often considered as a size-independent constant that depends only on the chemical composition of aerosol particles. The famous Malm’s reconstruction equation and subsequent revised methods express the extinction coefficient as a function of aerosol mass concentration and MEE. However, the used constant MEE does not take into account the effect of the size distribution of polydispersed chemical composition. Thus, a simplified expression of size-dependent MEE is required for accurate and conventional calculations of the aerosol extinction coefficient and also other optical properties. In this study, a simple parameterization of MEE of polydispersed aerosol particles was developed. The geometric volume–mean diameters of up to 10 µm with lognormal size distributions and varying geometric standard deviations were used to represent the sizes of various aerosol particles (i.e., ammonium sulfate and nitrate, elemental carbon, and sea salt). Integrating representations of separate small mode and large mode particles using a harmonic mean-type approximation generated the flexible and convenient parameterizations of MEE that can be readily used to process in situ observations and adopted in large-scale numerical models. The calculated MEE and the simple forcing efficiency using the method developed in this study showed high correlations with those calculated using the Mie theory without losing accuracy.