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Based on the criteria of equal total height and relative density, a series of glass fiber composite multi-layer graded corrugated sandwich panels (MLGCSPs) with different configurations is designed and fabricated by an in-house hot-molding secondary molding method. The effects of arrangement modes, graded corrugated cores and corrugated topologies on the vibration behavior of the present MLGCSPs are comprehensively investigated by the vibration shaker tests. The results reveal that the arrangement modes, graded arrangement and topologies of the corrugated cores all have significant influences on the frequency responses, and vibration reduction of the present MLGCSPs. The arrangement mode II and III generally have significantly higher resonant frequencies and vibration attenuation performance in the low frequency range, but the arrangement mode I shows better vibration reduction and isolation performance in the higher frequency range. It is possible to simultaneously achieve higher fundamental frequency and lower amplitude of the structures by optimizing the arrangement mode and gradient configuration. Subsequently, finite element simulation is carried out to systematically analyze the vibration responses of the composite MLGCSPs with different configurations. The consistency between numerical and experimental results is quite well. Finally, the effects of structural parameters on the vibration characteristics of the present structures are also revealed. Some conclusions are obtained, which can provide some meaningful guidelines for the vibration reduction design of such type of multi-layer structures. [ABSTRACT FROM AUTHOR]

Numerical simulation of the textile composites forming plays an important role in improving the manufacturing quality, reducing the manufacturing cycle, and manufacturing cost. The focus is on the shaping of one or several layers of G1151 interlock reinforcement. Based on the continuous approach at the macroscale, an approach using a hypoelastic behavior is proposed considering the specific interlock textile material behavior. The stress accumulation is carried out in frames defined by the direction of the warp and weft yarns. The approach is implemented in the commercial software Abaqus. By adding inter-layer contact properties, this approach can realize the simulation of multi-layers textile composites with different yarn orientation configurations. Experimental analyses have shown that this approach can correctly trace the specific behavior of interlock textile composites. [ABSTRACT FROM AUTHOR]

With the explosive development of many emerging fields, such as wearable devices, electronic skins, and flexible batteries, it urgently needs advanced polymer films with precisely controlled physical and chemical properties. Microfluidic technology that can be used to generate controllable laminar flow in the microchannels provides new opportunity for one-step fabricating such kind of polymer films. In this review, we summarize the development of advanced polymer films with accurately controlled thickness in micro/nanometer, and heterogeneous structures and compositions, taking advantage of the unique microfluidic laminar flow. We first briefly introduce the unique characteristics of microfluidic laminar flow, and the materials and related fabrication methods of microfluidic devices. Then, emphasis is placed on the preparation strategies of advanced polymer films based on microfluidic laminar flow. Finally, we put forward personal views on future trends of this promising technology and aim to promote the development of advanced polymer films by using the microfluidic laminar flow and potential applications in various fields.

The discussed study presents a new type of opto-electronic color filter designed for optical communication that could revolutionize both the signal processing field and the fiber optic communication industry. The study proposes a precise structure design for three reflective color filters based on a tri-layer configuration. This design includes a titanium dioxide layer on top, a semi-conductor silicon layer in the middle, and a silicon dioxide layer at the bottom, creating a DSD structure. This design presents three different filters for pure hues, namely magenta, yellow, and cyan. One of the significant advantages of this tri-layer design is the thickness of each material layer, which plays a vital role in producing better intensity values and purity of CMY colors. This study presents the design of the new filters that could potentially have a significant impact on the display industry, and life-saving medical equipment where fiber optics with multi-layer opto-electronic color filters are used. The novelty of this study lies in its precise structure design and the potential to generate superior results compared to existing color filters. This innovative design can potentially be implemented in various fields, such as display technology and medical equipment, to enhance their performance and accuracy. Overall, this study’s contribution highlights the potential advantages and usages of the proposed filters in various fields.

Exploring inexpensive and earth-abundant electrocatalysts for hydrogen evolution reactions is crucial in electrochemical sustainable chemistry field. In this work, a high-efficiency and inexpensive non-noble metal catalysts as alternatives to hydrogen evolution reaction (HER) was designed by one-step hydrothermal and two-step electrodeposition method. The as-prepared catalyst is composed of the synergistic MoS 2 –Co 3 S 4 layer decorated by ZnCo layered double hydroxides (ZnCo-LDH), which forms a multi-layer heterostructure (ZnCo/MoS 2 –Co 3 S 4 /NF). The synthesized ZnCo/MoS 2 –Co 3 S 4 /NF exhibits a small overpotential of 31 mV and a low Tafel plot of 53.13 mV dec−1 at a current density of 10 mA cm−2, which is close to the HER performance of the overpotential (26 mV) of Pt/C/NF. The synthesized ZnCo/MoS 2 –Co 3 S 4 /NF also has good stability in alkaline solution. The excellent electrochemical performance of ZnCo/MoS 2 –Co 3 S 4 /NF electrode originates from its abundant active sites and good electronic conductivity brought by the multilayer heterostructure. This work provides a simple and feasible way to design alkaline HER electrocatalysts by growing heterostructures on macroscopic substrates. [Display omitted] • An effective synthetic route for multi-layer heterostructures is proposed. • The multi-layer heterostructures improve electrochemical activity. • ZnCo/MoS 2 –Co 3 S 4 /NF has a good electrochemical performance in an alkaline solution. [ABSTRACT FROM AUTHOR]

The optimization of experimental results has repeatedly posed major challenges for scientist and engineers. In this work, a systematic multi-layer optimization scheme is proposed in conjunction with particle swarm optimization algorithm to locate a global optimum that fits a cost function. The technique utilizes SP-lines to form three-dimensional patches surfaces from experimental data in multi-layer fashion and incorporates a multi-layer search using particle swarm optimization. The novel technique is illustrated and verified over two layers of experimental data to show its effectiveness. [ABSTRACT FROM AUTHOR]

Monolithic three-dimensional (M3D) multi-layer nanoelectromechanical (NEM) memory switches are experimentally demonstrated for reconfigurable multi-path routing. The multi-layer NEM memory switch has moving mechanical beams in different metal layers which operate independently in a nonvolatile manner, including high impedance states. For example, double-layer NEM memory switches implement nine different memory states. It is predicted that our proposed ${n}$ -layer NEM memory switches utilizing ${n}$ metal layers will exhibit $3^{({n}-{1}{)}}\text{x}$ higher routing flexibility and ${n}\text{x}$ higher chip density than conventional single-layer NEM memory switches. [ABSTRACT FROM AUTHOR]

Human skin is a complex multilayered multiscale material that exhibits nonlinear and anisotropic mechanical behavior. It has been reported that its macroscopic behavior in terms of progression of wrinkles induced by aging is strongly dependent on its microscopic composition in terms of collagen fibers in the dermis layer. In the present work, a multiscale four-layer 2D finite element model of the skin was developed and implemented in Matlab code. The focus here was to investigate the effects of dermal collagen on the macroscopic mechanical behavior of the skin. The skin was modeled by a continuum model composed of four layers: the Stratum Corneum, the epidermis, the dermis, and the hypodermis. The geometry of the different layers of the skin was represented in a 2D model with their respective thicknesses and material properties taken from literature data. The macroscopic behavior of the dermis was modeled with a nonlinear multiscale approach based on a multiscale elastic model of collagen structure going from cross-linked molecules to the collagen fiber, combined with a Mori-Tanaka homogenization scheme. The model includes the nonlinear elasticity of the collagen fiber density, the fiber radius, the undulation, and the fiber orientation. An axial tension was applied incrementally to the lateral surfaces of the skin model. A parametric study was performed in order to investigate the effect of the collagen constituents on the macroscopic skin mechanical behavior in terms of the predicted macroscopic stress-strain curve of the skin. The results of the FE computations under uniaxial tension showed that the different layers undergo different strains, leading to a difference in the transversal deformation at the top surface. In addition, the parametric study revealed a strong correlation between macroscopic skin elasticity and its collagen structure. [ABSTRACT FROM AUTHOR]

Despite the potential benefits of family relationships and family events, insufficient studies have been undertaken to address how to overcome their obstacles. So, the main objective of this paper is to present a systematic model for prioritizing family members in response to standing limitations on family relationships. For this, the chosen methodology is conceptual sequence modeling, and the proposed model is optimized to include family membership motives and demotivators. Moreover, multiple criteria for the membership nominations are included to respond to the dynamic scenarios and complexity of decision-making. The feasibility of the proposed model is proven in a numerical case. Thus, the contribution of the proposed model is predictable to be from event planning to relative relationship management.

Non-local Means (NLMs) play essential roles in image denoising, restoration, inpainting, etc., due to its simple theory but effective performance. However, when the noise increases, the denoising accuracy of NLMs decreases significantly. This paper further develop the NLMs-based denoising method to remove noise with less loss of image details. It is realized by embedding an optimal graph edge weights driven NLMs kernel into a multi-layer residual compensation framework. Unlike the patch similarity-based weights in the traditional NLMs filters, the edge weights derived from the optimal graph Laplacian regularization consider (1) the distance between the target pixel and the candidate pixel, (2) the local gradient and (3) the patch similarity. After defining the weights, the graph-based NLMs kernel is then put into a multi-layer framework. The corresponding primal and residual terms at each layer are finally fused with learned weights to recover the image. Experimental results show that our method is effective and robust, especially for piecewise smooth images. [ABSTRACT FROM AUTHOR]

Visual detection of hydrogen is important for hydrogen-powered vehicles and hydrogen fuel stations. However, there are few studies on such the sensing approach, particularly solving challenges about the endurance or reusability of the sensors. Here, our development of superior reversible gasochromic hydrogen sensors based on a novel combination of a multi-layered Pt–Ni catalyst and a mixed-phase MoO 3 active layer is introduced. The mixed α and β phases in the MoO 3 layer can provide more high-energy sites for gasochromic reactions. The Pt–Ni catalyst, where Ni serves as a modifier of surface atoms' diffusivity, successfully converts the mostly irreversible gasochromic sensing mode of MoO 3 to the reversible gasochromic mode. Our hydrogen sensor shows coloration from grey to navy blue within 30 s, and its recovery occurs within 50 s. Furthermore, it can detect H 2 gas (5–1000 ppm) in both optical and electrical modes. Notably, our sensor is all constructed through dry processes, raising its potential for large-scale manufacture and integration. [Display omitted] • Mixed α and β phases of MoO 3 serving a crucial basis for the reversible gasochromism. • Bimodal sensing capabilities of our Pt–Ni/MoO 3 reversible chemochromic material. • Multi-layered Pt–Ni catalyst, where Ni acts as a modifier of surface atoms' diffusivity. • Controlled multi-layering of Pt and Ni boosting the hydrogen detection of MoO 3. [ABSTRACT FROM AUTHOR]

Glass is an ideal material for microfluidic chips because of its pressure resistance, chemical stability, optical transparency, and thermal stability. Two-layer or three-layer microfluidic glass chips, composed of one or two cover layers and one structural layer, have been widely applied to two-dimensional microfluidic systems. Due to the fabrication difficulties in aligning and bonding multiple glass layers, multi-layer glass chips (more than three layers) are underutilized, although they are essential to deliver more complicated microfluidic functionalities and achieve more accurate microfluidic manipulations. This work proposes a fabrication process based on rapid laser cutting of single glass layers and one-time thermocompression bonding of multi-layer chips and demonstrated it with a five-layer microfluidic chip for three-dimensional (3D) hydrodynamic focusing. The pressure and temperature are the key parameters for multi-layer bonding, which are experimentally determined to be 0.4 MPa and 605 ℃. Five-layer glass microfluidic chips could be fabricated within 6 h with a bonding strength of 0.6 MPa. This simple, easy-to-operate fabrication method for the rapid production of multi-layer glass microfluidic chips will be conducive to the wide application of multi-layer microfluidic glass chips. [ABSTRACT FROM AUTHOR]

[Display omitted] • Femtosecond laser processing was applied to a multi-layered, steel on copper substrate. • Self-organized micro/nanostructures formed on the surface of the steel foil and acted as precursor sites for structures to develop on the underlying copper. • Cross-sectional analysis, chemical analysis, and height measurements were performed to understand the formation of the multi-layered material. Femtosecond lasers can be used to create self-organized micro/nanostructures on the surface of most materials. However, on copper, these structures require significantly higher laser fluence when compared to other metals. We report a method to create self-organized structures on copper by clamping a foil of stainless steel on the copper surface prior to laser processing. All samples reported are processed using a peak fluence of 2.71 J/cm2, which is below the fluence threshold for self-organized micro/nanostructure formation on copper. When stainless steel is layered on copper, structures are created that consist of both stainless steel and copper at pulse counts of 998 and 1,197. With increased pulse count, the thickness of the stainless steel layer decreases. For pulse counts of 1,497 and higher, the permanent structures are completely composed of copper. Using these same parameters, but without the stainless steel foil on the copper, the laser processing formed agglomerations of nanoparticles on the surface regardless of pulse count. The structure morphology and chemistry of the surface features are characterized with surface and subsurface analysis to study the material make-up of the structures and investigate the pulse count necessary to fully remove the stainless steel, leaving a structured copper surface. [ABSTRACT FROM AUTHOR]

Effective water management in agriculture requires a comprehensive understanding of the distribution of water content throughout the soil profile to the root zone. This knowledge empowers farmers and water managers to make informed decisions regarding irrigation timing and quantity for optimizing crop growth. To estimate the soil moisture profile, this study utilized combined L- and P-band radiometry with four incoherent radiative transfer models, including three multi-layer models based on a zero-order (IZ), first order (IF) and incoherent solution (IS) approximation, and a uniform model (UM) model, as well as the stratified coherent Njoku model (NM). The impact of vegetation was considered through the conventional tau-omega model. Linear (Li) and second-order polynomial (Pn2) functions were used to represent the shape of the soil moisture profile. Observations from a tower-based experiment under various land cover conditions, including bare, bare-weed, grass, wheat and corn, were used. The root mean square error (RMSE) was calculated between the observed and estimated soil moisture profiles. The results revealed comparable RMSE values for all five radiative transfer models, with the Pn2 function outperforming the Li function in estimating the soil moisture of deeper layers. Regardless of the employed radiative transfer model, utilizing combined L- and P-band radiometry and employing the Pn2 function yielded RMSEs of 0.03 m3/m3, 0.08 m3/m3, and 0.1 m3/m3 over depths of 0–5 cm, 0–30 cm, and 0–60 cm, respectively. A comparison between the incoherent and stratified coherent Njoku radiative transfer models indicated that the latter slightly outperformed the former under the dry bare soil conditions, exhibiting a 0.003 m3/m3 lower RMSE at the surface while nearly equal performance at the bottom of the profile. Furthermore, the multi-layer incoherent radiative transfer models provided only a slightly better estimate than the UM model, especially for shallow layers, with the average RMSE over the entire profile being 0.002 m3/m3 lower. Consequently, the complexity of the multi-layer incoherent and coherent radiative transfer models is not justified for this small gain in performance. The depth for which the UM model provided a reasonable soil moisture estimate ranged from 1 cm (under wet corn) to 39 cm (under dry bare), and depended on the soil moisture profile gradient and soil moisture content values in the shallow layers. These important findings pave the way for estimating soil moisture profile on a global scale using combined L- and P-band radiometry from future satellite missions. • Combined L-band and P-band radiometry was used to estimate soil moisture profiles. • Second-order polynomial surpassed linear function in estimating deep soil moisture. • Multilayer coherent models slightly outperformed uniform model for shallow layers. • Differences between models were minor, particularly for second-order polynomial. • The uniform model estimates: 1 cm (wet corn) to 39 cm (dry bare). [ABSTRACT FROM AUTHOR]

This paper presents an accurate procedure to design, characterize and test a radome for millimeter-wave applications. In this procedure, an accurate analytical model is presented to design a radome structure that takes into consideration the bandwidth, losses, reflections and depolarization factor as a function of frequency and incident angle. To guarantee a good operational electrical performance, the proposed procedure includes a material characterization and accurate test procedure based on the free-space Gaussian beam method and time gating filtering technique. Four radomes (two-monolithic and two A-sandwich) at 82 GHz and 94 GHz are designed, characterized and tested to validate the proposed technique. Results obtained with this procedure are compared with numerical simulations and experimental results. This method is shown to be accurate and versatile for radomes in mm-Wave applications.

This paper presents a new design technique to develop a multi-layer radome for ultra-wide-band, dual-polarized radar and communication systems. In the proposed technique, a multi-layer radome is designed using a combination of A-sandwich structures, which are not used in conventional multi-layer radomes. In contrast with conventional radomes, this technique enables a substantial increase of bandwidth with a negligible change in the overall radome thickness. In addition, it provides excellent RF performance, thermal isolation, and mechanical strength. Three different multi-layer radomes for different bandwidths are designed. Parameters such as co-polarization mismatch and depolarization ratio are used to evaluate the proposed dual-polarized radome as a function of incident angle and frequency. To validate this new technique, a 5A-sandwich radome is designed to operate from 1 GHz to 14 GHz and its RF performance is evaluated by measuring S-parameters. The proposed radome is further investigated by measuring the radiation patterns of horn antennas at different bands (S-, C-, X- and Ku-bands) with and without the radomes. The measured losses recorded are below 0.5 dB with an absolute error less than 0.05 dB between the calculations and measurements. An S-band electronically scanned active phased array antenna is also used to evaluate the radome as a function of incident angles. In this case, the maximum recorded losses are below 0.4 dB and the absolute errors between the calculations and measurements are below 0.1 dB. The proposed technique and radome can be used in different applications such as surveillance systems, earth exploration satellite, aeronautical radio-navigation, and especially in dual-polarized weather radars that require a high polarization performance.

Abstract The pulse thermography (PT) technique was applied to the detection of the delamination of a multi-layered coating system composed of mullite/Si onto a reaction-bonded SiC substrate. The potential evaluation was carried out in order to detect internal delamination in multi-layered material system. Moreover, the observation of the cross sections and 3D views obtained by X-ray computed tomography (CT) indicated that the delamination occurred at the interface between the top coat and the bond coat layers. The changes in the temperature distribution obtained by PT indicated the existence of a delamination area in the top coat layer of the mullite. In particular, the lower temperature region corresponded to the delamination area. The experimental results confirmed that the PT technique is effective with respect to the internal delamination of multi-layered coating system.

This study stacked a thin, dense BCuP-5 (Cu-Ag-P based filler metal) on a Cu-plate using the laser cladding (L.C) process to develop a method to manufacture Ag reducing multilayer clad electrical contact material with an Ag-M(O)/Ag/Cu/BCuP-5 structure. Then, the microstructure and macroscopic properties of the manufactured BCuP-5 coating layer were analyzed. The thickness of the manufactured coating layer was approximately 1.7 mm (maximum). Microstructural observation of the coating layer identified Cu, Ag and Cu-Ag-Cu3P ternary eutectic phases like those in the initial BcuP-5 powder. To evaluate the properties of the manufactured coating layer, hardness and adhesion strength tests were performed. The average hardness of the laser cladded coating layer was 183.2 Hv, which is 2.6 times greater than conventional brazed BcuP-5. The average pull-off strength measured using the stud pull test was 341.6 kg/cm2. Cross-sectional observation of the pulled-off material confirmed that the coating layer and substrate maintained a firm adhesion after pull-off. Thus, the actual adhesion strength of Cu/BcuP-5 was inferred to be greater than 341.6 kg/cm2. Based on the above findings, it was confirmed that it is possible to manufacture a sound Ag reducing multilayer clad electrical contact material using the laser cladding process.

Multispectral remote sensing images have shown unique advantages in many fields, including military and civilian use. Facing the difficulty in processing cloud contaminated remote sensing images, this paper proposes a multispectral remote sensing image enhancement algorithm. A model is constructed from the aspects of cloud detection and image enhancement. In the cloud detection stage, clouds are divided into thick clouds and thin clouds according to the cloud transmitability in multi-spectral images, and a multi-layer cloud detection model is established. From the perspective of traditional image processing, a bimodal pre-detection algorithm is constructed to achieve thick cloud extraction. From the perspective of deep learning, the MobileNet algorithm structure is improved to achieve thin cloud extraction. Faced with the problem of insufficient training samples, a self-supervised network is constructed to achieve training, so as to meet the requirements of high precision and high efficiency cloud detection under the condition of small samples. In the image enhancement stage, the area where the ground objects are located is determined first. Then, from the perspective of compressed sensing, the signal is analyzed from the perspective of time and frequency domains. Specifically, the inter-frame information of hyperspectral images is analyzed to construct a sparse representation model based on the principle of compressed sensing. Finally, image enhancement is achieved. The experimental comparison between our algorithm and other algorithms shows that the average Area Overlap Measure (AOM) of the proposed algorithm reaches 0.83 and the Average Gradient (AG) of the proposed algorithm reaches 12.7, which is better than the other seven algorithms by average AG 2.

Completion systems are important components of hydrocarbon field development. As the link between the reservoir and surface facilities, completions need to be designed to maximize hydrocarbon recovery and withstand consistently changing conditions for years, within the safety requirements. However, designing completion for a well comprising a multi-layer and multi-fluid reservoir is quite challenging. The completion design must use the right materials and be able to safely produce single, as well as commingle products, and add any artificial lifts, depending on the method with the most optimum value. This paper, therefore, discusses the model development of completion design for an offshore well AA-01, one of the offshore wells with multi-layer and multi-fluid reservoir systems in Indonesia. Well AA-01 penetrates two productive layers, the upper layer AA-U1, and the lower layer AA-L2. The upper layer is a gas reservoir with initial gas in place of 1440 MMSCF, while the lower layer is an oil reservoir with initial oil in place of 6.1 MMSTB. In addition, the model design used available field data, for instance, PVT and DST, from well X. The base well completion was also used to model the completion design in software. Meanwhile, commercial software was utilized to estimate the well hydrocarbon recovery. Subsequently, several designs were tested, and the design with maximum production as well as hydrocarbon recovery was selected. The completion design selected comprises 9⅝ inch 47 ppf L-80 production casing, as well as 7⅝ inch 29.7 ppf L-80 liner, and produced commingle with oil and gas recovery of about 50.16% and 92.3%, respectively, in 5 years production

The terahertz frequency band becomes a growth platform of various applications from medical imaging to indoor communications. Emerging new materials such as graphene and developing reliable models paved the design way for graphene-based microstructures. This paper proposes a relatively comprehensive design methodology for graphene-based multi-layers structures. The procedure includes forming device geometry, finding graphene patterns, material types, and optimizing control parameters. In this way, a reconfigurable THz wave absorber is introduced. Exploiting a multi bias scheme for a single graphene layer provide opportunity to affect device reaction via bias itself and patterns period simultaneously which increase adjustability of device response. Also using two different graphene patterns turns the device complex regarding design optimizations and simulations. So a well-known and simple circuit representation is used to design the proposed methodology and the proposed device. Knowing equivalent circuit models for the device elements triggers developing an evolutionary algorithm to search for a desirable response. In this context, the paper suggests using a weighted binary matrix in the design process. The matrix determines bias schemes for each layer. Then an evolutionary algorithm optimizes whole biases values. The expectation is more in-depth control over the device behavior via biases values. This is verified by exploited circuit model formulations and Finite Element Method (FEM) as numerical simulation for a unique three layers device.

In this report, we have clarified the cause of damage to the bellows exhaust pipe installed in the hydraulic excavator, and the influence of the seam welded part of the bellows on the damage to ensure the strength reliability of the bellows. First, the fracture surface of the damaged bellows was observed which was installed in the prototype machine of the hydraulic excavator, and it was clarified that the damage cause was the fatigue fracture starting from the seam welded part. Next, the natural frequencies of the engine exhaust system with bellows were derived by eigenvalue analysis, and the main stress frequencies were obtained by the frequency analysis of the stress time waveform measured in the actual machine test. By comparing the natural frequencies and the main stress frequencies, it was confirmed that the repeated shear deformation of the bellows due to the 2nd vibration mode was the main cause of the bellows breakage. Finally, a fatigue test simulating the shear deformation of the bellows was carried out, and it was confirmed that the damage of bellows could be reproduced by the fatigue test and that both inner and outer layers were fatigue-fractured at the seam welded parts. From the above, it can be judged that the seam welded part is the weakest part of the bellows, and the strength reliability can be improved by removing the seam welded part from the high stress part of the bellows.

Purpose: The aim of this study was to analyze the clinical results provided by multi-layer cell-free scaffolds for the treatment of knee osteochondral defects. Methods: A systematic review was performed on PubMed, Web of Science, and Cochrane to identify studies evaluating the clinical efficacy of cell-free osteochondral scaffolds for knee lesions. A meta-analysis was performed on articles reporting results of the International Knee Documentation Committee (IKDC) and Tegner scores. The scores were analyzed as improvement from baseline to 1, 2, and ≥ 3 years of follow-up. The modified Coleman Methodology Score was used to assess the study methodology. Results: A total of 34 studies (1022 patients) with a mean follow-up of 35 months was included. Only three osteochondral scaffolds have been investigated in clinical trials: while TruFit® has been withdrawn from the market for the questionable results, the analysis of MaioRegen and Agili-C™ provided clinical improvements at 1, 2, and ≥ 3 years of follow-up (all significantly higher than the baseline, p < 0.05), although with a limited recovery of the sport-activity level. A low rate of adverse events and an overall failure rate of 7.0% were observed, but the overall evidence level of the available studies is limited. Conclusions: Multi-layer scaffolds may provide clinical benefits for the treatment of knee osteochondral lesions at short- and mid-term follow-up and with a low number of failures, although the sport-activity level obtained seems to be limited. Further research with high-level studies is needed to confirm the role of multi-layer scaffold for the treatment of knee osteochondral lesions. [ABSTRACT FROM AUTHOR]

To reduce loss of hydrogen in storage vessels with high energy-to-weight-ratio, new materials, especially polymers, have to be developed as barrier materials. Very established methods for characterization of barrier materials with permeation measurements are the time-lag and flow rate method along with the differential pressure method, which resembles the nature of hydrogen vessel systems very well. Long measurement durations are necessary to gain suitable measurement data for these evaluation methods, and often restrictive conditions have to be fullfilled. For these reasons, common models for hydrogen permeation through single-layer and multi-layer membranes, as well as models for hydrogen gas properties were collected and reviewed. Using current computer power together with these models can reduce measurement time for characterization of the barrier properties of materials, while additional information about the quality of the measurement results is obtained. • Review of models for single- and multi-layered membrane permeation. • Recommendation of curve fitting instead of time lag or flow rate measurements. • Empirical equations of state for viscosity and density of hydrogen. • Discussion of the influence of porous plates on permeation measurements. [ABSTRACT FROM AUTHOR]

Background: Single liquid biopsy analytes (LBAs) have been utilized for therapy selection in metastatic breast cancer (MBC). We performed integrative statistical analyses to examine the clinical relevance of using multiple LBAs: matched circulating tumor cell (CTC) mRNA, CTC genomic DNA (gDNA), extracellular vesicle (EV) mRNA, and cell-free DNA (cfDNA). Methods: Blood was drawn from 26 hormone receptor-positive, HER2-negative MBC patients. CTC mRNA and EV mRNA were analyzed using a multi-marker qPCR. Plasma from CTC-depleted blood was utilized for cfDNA isolation. gDNA from CTCs was isolated from mRNA-depleted CTC lysates. CTC gDNA and cfDNA were analyzed by targeted sequencing. Hierarchical clustering was performed within each analyte, and its results were combined into a score termed Evaluation of multiple Liquid biopsy analytes In Metastatic breast cancer patients All from one blood sample (ELIMA.score), which calculates the contribution of each analyte to the overall survival prediction. Singular value decomposition (SVD), mutual information calculation, k-means clustering, and graph-theoretic analysis were conducted to elucidate the dependence between individual analytes. Results: A combination of two/three/four LBAs increased the prevalence of patients with actionable signals. Aggregating the results of hierarchical clustering of individual LBAs into the ELIMA.score resulted in a highly significant correlation with overall survival, thereby bolstering evidence for the additive value of using multiple LBAs. Computation of mutual information indicated that none of the LBAs is independent of the others, but the ability of a single LBA to describe the others is rather limited—only CTC gDNA could partially describe the other three LBAs. SVD revealed that the strongest singular vectors originate from all four LBAs, but a majority originated from CTC gDNA. After k-means clustering of patients based on parameters of all four LBAs, the graph-theoretic analysis revealed CTC ERBB2 variants only in patients belonging to one particular cluster. Conclusions: The additional benefits of using all four LBAs were objectively demonstrated in this pilot study, which also indicated a relative dominance of CTC gDNA over the other LBAs. Consequently, a multi-parametric liquid biopsy approach deconvolutes the genomic and transcriptomic complexity and should be considered in clinical practice. [ABSTRACT FROM AUTHOR]

Wire arc additive manufacturing (WAAM) is a direct energy deposition (DED) process with high deposition rates, but deformation and distortion can occur due to the high energy input and resulting strains. Despite great efforts, the prediction of distortion and resulting geometry in additive manufacturing processes using WAAM remains challenging. In this work, an artificial neural network (ANN) is established to predict welding distortion and geometric accuracy for multilayer WAAM structures. For demonstration purposes, the ANN creation process is presented on a smaller scale for multilayer beads on plate welds on a thin substrate sheet. Multiple concepts for the creation of ANNs and the handling of outliers are developed, implemented, and compared. Good results have been achieved by applying an enhanced ANN using deformation and geometry from the previously deposited layer. With further adaptions to this method, a prediction of additive welded structures, geometries, and shapes in defined segments is conceivable, which would enable a multitude of applications for ANNs in the WAAM-Process, especially for applications closer to industrial use cases. It would be feasible to use them as preparatory measures for multi-segmented structures as well as an application during the welding process to continuously adapt parameters for a higher resulting component quality. [ABSTRACT FROM AUTHOR]

The dense (working) and porous (insulation) refractories are generally used for the lining of any kind of furnaces or kilns. The present investigation provides a new designed spinel (MgAl 2 O 4) light weight refractory, which retains both working and insulation parts in a single specimen. The multi-layered refractories are fabricated by varying the amount of pore-forming agent (rice powder) and sintering aids (waste rice husk ash (RHA)) in the different layers. A porosity gradient is developed by the incorporation of intermediate layers in between the insulation and working layer. At 1550 °C with 3 h soaking sample retains good compressive strength (92.43 MPa), low apparent porosity (8.72%), good cement clinker corrosion resistance in the working layer along with reasonable strength (31.72 MPa), and low thermal conductivity (0.146 W/m·k) in the insulation layer. These promising results may encourage the refractory industries in developing the light weight multi-layered refractory for cement kiln. • A refractory contains a combination of dense and porous layers for cement kilns. • Utilize of multi-layered refractory for cutting down the total mass of kilns. • A porosity gradient is developed through the slight changing of the composition. • Rice husk ash is used as sintering aid and rice powder as pore-forming agent. [ABSTRACT FROM AUTHOR]

Person re-identification(Re-ID) has attracted increasing attention in the field of computer vision due to its great significance for the potential real-world applications. Profited from the success of convolutional neural networks(CNNs), existing multi-layer approaches leverage different scales of convolutional layers to learn more discriminative features, improving the Re-ID performance to some extent. However, these methods do not further explore whether all the scales of convolutional layers are positive for person re-identification. In this work, we propose a novel non-full multi-layer(NFML) network, which can jointly learn discriminative feature embeddings from positive multiple layers with the manner of combining global and local cues. Moreover, considering few works focus on how to effectively handle the feature maps, a simple yet effective feature progressing module named Pooling Batch Normalization(PBN), consisting of pooling, reduction and batch normalization operations, is introduced to optimize the model structure and further improve the Re-ID performance. Results on three mainstream benchmark datasets Market-1501, DukeMTMC-reID and CUHK03 demonstrate that our method can significantly boost the performances, outperforming the state-of-the-art methods. [ABSTRACT FROM AUTHOR]

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Pure oxygen is mainly produced by separating oxygen from the air. Oxygen separation membranes using mixed oxide ionic-electronic conductor (MIEC) selectively separate high-purity oxygen via oxide ions using the oxygen partial pressure difference on both sides of the membrane as a driving force. It is expected to be industrially put into practical use as a device suitable for on-site oxygen production. In order to improve the oxygen separation efficiency, it is important to increase the surface reaction area and reduce the thickness of the membrane. A multilayered structure composed of "porous layer / dense thin layer / porous support layer" is suitable for the purpose. Electrophoretic deposition (EPD) is a very suitable method for forming such a multilayered structure. This review introduces the processing viewpoints to optimize various conditions such as suspension preparation conditions, EPD conditions, and co-sintering conditions. Finally, the oxygen separation performance is tested for the obtained membrane and the importance of microstructural design and process selection in improving oxygen separation performance is discussed. [ABSTRACT FROM AUTHOR]

Artificial neural networks (ANNs) are one of the hottest topics in computer science and artificial intelligence due to their potential and advantages in analyzing real-world problems in various disciplines, including but not limited to physics, biology, chemistry, and engineering. However, ANNs lack several key characteristics of biological neural networks, such as sparsity, scale-freeness, and small-worldness. The concept of sparse and scale-free neural networks has been introduced to fill this gap. Network sparsity is implemented by removing weak weights between neurons during the learning process and replacing them with random weights. When the network is initialized, the neural network is fully connected, which means the number of weights is four times the number of neurons. In this study, considering that a biological neural network has some degree of initial sparsity, we design an ANN with a prescribed level of initial sparsity. The neural network is tested on handwritten digits, Arabic characters, CIFAR-10, and Reuters newswire topics. Simulations show that it is possible to reduce the number of weights by up to 50% without losing prediction accuracy. Moreover, in both cases, the testing time is dramatically reduced compared with fully connected ANNs. [ABSTRACT FROM AUTHOR]

Humans can detect outliers just by using only observations of normal samples. Similarly, one-class classification (OCC) uses only normal samples to train a classification model which can be used for outlier detection. This paper proposes a multi-layer architecture for OCC by stacking various graph-embedded kernel ridge regression (KRR)-based autoencoders in a hierarchical fashion. We formulate the autoencoders under the graph-embedding framework to exploit local and global variance criteria. The use of multiple autoencoder layers allows us to project the input features into a new feature space on which we apply a graph-embedded regression-based one-class classifier. We build the proposed hierarchical OCC architecture in a progressive manner and optimize the parameters of each of the successive layers based on closed-form solutions. The performance of the proposed method is evaluated on 21 balanced and 20 imbalanced datasets. The effectiveness of the proposed method is indicated by the experimental results over 11 existing state-of-the-art kernel-based one-class classifiers. Friedman test is also performed to verify the statistical significance of the obtained results. By using two types of graph-embedding, 4 variants of graph-embedded multi-layer KRR-based one-class classification methods are presented in this paper. All 4 variants have performed better than the existing one-class classifiers in terms of the various performance metrics. Hence, they can be a viable alternative for OCC for a wide range of one-class classification tasks. As a future extension, various other autoencoder variants can be applied within the proposed architecture to increase efficiency and performance. [ABSTRACT FROM AUTHOR]

This paper reports an integration of dual band microstrip antenna with thin film amorphous silicon solar cell which creates a wearable system to harvest microwave energy. The multiple layers in the encapsulation of the thin film solar cell are used as a substrate for microstrip antenna. The rectifier and matching circuit are designed on cotton jeans material and the whole system is mechanically supported by the foam of 5 mm thick. The performance of the antenna is studied for the mechanical bending condition. The device has maintained good power conversion efficiency. The efficiency of the voltage doubler is tested by varying radio frequency power levels from −30 to10 dBm. The voltage doubler conversion efficiency at 1.85 and 2.45 GHz are 58 and 43%, respectively, for a load of 7.5 kΩ for an input power level of −5 dBm. [ABSTRACT FROM AUTHOR]

A design method for a compact multilayered stepped impedance resonator (SIR) filter is proposed. The size of the implemented filter was reduced by 37 % compared with that of conventional SIR filter structures. Interdigital coupled lines were used to obtain broadband characteristics, and the proposed filter exhibits high frequency selectivity by implementing transmission zeros at the lower and upper stopband frequencies. The implemented filter provides excellent filter characteristics, exhibiting an insertion loss of <1.2 dB with >10 dB return loss in the frequency range of 3.8～12.8 GHz. [ABSTRACT FROM AUTHOR]

In order to understand the fracture resistance of nanocrystalline thin films, it is necessary to assess nanoscopic multiaxial stress fields accompanying crack growth during irreversible deformation. Here, a clamped cantilever with dimensions of 200 × 23.7 × 40 μm3 was machined by focused ion beam milling from a thin film composed of four alternating CrN and Cr layers. The cantilever was loaded to 460 mN in two steps and multiaxial strain distributions were determined by in situ cross-sectional X-ray nanodiffraction. Characterization in as-deposited state revealed the depth variation of fibre texture and residual stress across the layers. The in situ experiment indicated a strong influence of the residual stresses on the cross-sectional stress fields evolution and crack arrest capability at the CrN-Cr interface. In detail, an effective negative stress intensity of −5.9 ± 0.4 MPa m½ arose as a consequence of the residual stress state. Crack growth in the notched Cr layer occurred at a critical stress intensity of 2.8 ± 0.5 MPa m½. The results were complemented by two-dimensional numerical simulation to gain further insight into the elastic-plastic deformation evolution. The quantitative experimental and modelling results elucidate the stepwise nature of fracture advancement across the alternating brittle and ductile layers and their interfaces.

Abstract Purpose The aim of this study was to analyze the clinical results provided by multi‐layer cell‐free scaffolds for the treatment of knee osteochondral defects. Methods A systematic review was performed on PubMed, Web of Science, and Cochrane to identify studies evaluating the clinical efficacy of cell‐free osteochondral scaffolds for knee lesions. A meta‐analysis was performed on articles reporting results of the International Knee Documentation Committee (IKDC) and Tegner scores. The scores were analyzed as improvement from baseline to 1, 2, and ≥ 3 years of follow‐up. The modified Coleman Methodology Score was used to assess the study methodology. Results A total of 34 studies (1022 patients) with a mean follow‐up of 35 months was included. Only three osteochondral scaffolds have been investigated in clinical trials: while TruFit® has been withdrawn from the market for the questionable results, the analysis of MaioRegen and Agili‐C™ provided clinical improvements at 1, 2, and ≥ 3 years of follow‐up (all significantly higher than the baseline, p

Quality of CPL fluorophore is defined by the vectors of electric dipole transition moment and imaginary magnetic dipole transition moment. The aim of this review is to introduce readers to a chiral moiety applicable to CPL studies focusing on chiral cyclophanes because the rigid cyclophanes are able to hold the vector directions of electric dipole transition moment and imaginary magnetic dipole transition moment.

With the development of computer technology and artificial intelligence (AI), service robots are widely used in our daily life. While the manufacturing cost of the robots is too expensive for most small technology companies. The biggest technical limitations are the design of the robot service and the resources sharing of the robot groups. As far as we know, there is no complete and open-source service robot cloud service platform. To solve the above problems, in this paper, a novel robot cloud platform called cloud robotics intelligent cloud platform (CRICP) is designed, which consists of gateway layer, an interface layer, service pool, and algorithm layer. Gateway layer mainly solves the problem of robot access control and service invocation requests scheduling. In addition, a standardized access method is proposed to overcome the problem that heterogeneous service robots cannot access the cloud platform. Interface layer is responsible for protocol injection, including motoring protocol, a management protocol, and other algorithms invocation protocol or service invocation interfaces protocol. Service Pool consists of different kinds of robot services which could scale based on the historical data analysis. In Algorithm layer, we can implement machine learning (ML) algorithm, deep learning (DL) algorithm, distributed algorithm, and so on. Finally, voice recognition service invocation experiment and cloud service dynamic scaling test are taken as an example to verify the availability and accuracy of our platform. Moreover, the compared results with a local framework and SOA also verifies the superiority of our platform.

This paper reports design of a very low-cost (less than 2000 USD) chemical vapour deposition (CVD) reactor for graphene synthesis, based on readily available off-the-shelf components. The reactor is intended for in-house graphene synthesis in metamaterial research. The reactor was manufactured and tested, and synthesized graphene samples were characterized by Raman spectroscopy. Measurement results revealed high quality of synthesized single and multi-layer graphene samples.

This paper conducts a one-dimensional theoretical study on the electrochemical phenomenon in the dual-layer cathode electrode of polymer electrolyte fuel cells (PEFCs) with varying sub-layer thicknesses, and further extends the analysis to a triple-layer configuration. We obtain the explicit solution for a general dual-layer configuration with different layer thicknesses. Distributions of the key quantities such as the local reaction current and electrolyte overpotential are exhibited at different ratios of the ionic conductivities, electrochemical kinetics, and layer thicknesses. Based on the dual-layer approach, we further derive the explicit solutions for a triple-layer electrode. Sub-layer performances are plotted and compared. The results indicate that the layer adjacent to the electrolyte membrane may contribute a major part of the electrode faradic current production. The theoretical analysis presented in this paper can be applied to assist electrode development through complicated multi-layer configuration for cost-effective high performance electrodes. © 2010 Elsevier Ltd.