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Rare earth garnet (R3Fe5O12, RIG) single crystals are the most ideal magneto-optical medium for optical isolators for wavelength longer than 1.1 μm, which has been commercially used in optical fiber communications. However, it is still a great challenge to grow large size RIG single crystals. In this work, high-quality Y3Fe5O12 (YIG) and Bi0.9Tb2.1Fe5O12 (Bi:TIG) single crystals were successfully grown by the flux–Bridgman method for the first time. The as-grown crystals up to 20 mm in diameter was obtained using the PbO–B2O3 flux. The transmittance of YIG crystals is over 75% in the region of 1100–2500 nm. TIG crystals also have good transmittance in the range of 1100–1700 nm, and show typical Tb absorption from 1700 to 2500 nm. The specific Faraday rotations of YIG and Bi0.9Tb2.1Fe5O12 crystals are 185 (°)/cm and –1250 (°)/cm at 1550 nm, which are comparable to the commercial RIG crystals grown by LPE method. The present results indicate that flux–Bridgman method shows great potential to grow large size and high-quality RIG magneto-optical crystals.

In order to determine the synergistic effects of the mixed additives of Fe and other catalysts on the yields and characteristics of bio-oil products, hydrothermal liquefaction (HTL) of pinewood sawdust (PW) was performed at 300 °C for 30 min (biomass/water mass ratio = 1:10) in the presence of metallic iron (Fe), other homogeneous/heterogeneous catalysts (Na2CO3, NaOH, FeSO4, MgO, Ru/C, FeS), as well as mixed additives. The results indicated that the metallic Fe could increase the yield and promote the degree of hydrodeoxygenation of bio-oil products. Noticeable synergistic effects on improving the bio-oil yields were found in the presence of mixed additives of Fe and an alkali catalyst (Na2CO3/NaOH) or FeS. The maximum bio-oil yield and the most energy recovery from bio-oil (81%) were obtained with Fe + Na2CO3. In addition, the combination of Fe + Ru/C produced bio-oil with the highest carbon and hydrogen contents, the highest HHV (30.93 MJ/kg), as well as the lowest contents of oxygenated compounds and the largest amount of hydrocarbons. In summary, this work demonstrates the synergistic effects of the mixed additives of Fe and several catalysts (Na2CO3, FeS and Ru/C) in HTL of woody biomass, promoting both yields and quality of bio-oil products.

A typical three-dimensional finite element model for a fuel assembly is established, which is composed of 16 monolithic U-10Mo fuel plates and Al alloy frame. The distribution and evolution results of temperature, displacement and stresses/strains in all the parts are numerically obtained and analyzed with a self-developed code of FUELTM. The simulation results indicate that (1) the out-of-plane displacements of Al alloy side plates are mainly attributed to the bending deformations; (2) enhanced out-of-plane displacements appear in fuel plates adjacent to the outside Al plates, which results from the occurred bending deformations due to the applied constraints of outside Al plates; (3) an intense interaction of fuel foil with the cladding occurs near the foil edge, which appears more heavily in the fuel plates adjacent to the outside Al plates. The maximum first principal stresses in the fuel foil are similar for all the fuel plates and appear near the fuel foil edge; while, the through-thickness creep strains of fuel foil in the fuel plate near the central region of fuel assembly are larger, and the induced creep damage might weaken the fuel skeleton strength and raise the fuel failure risk.

This article proposes an ultrawide output range ${LLC}$ resonant converter based on adjustable turns ratio transformer and reconfigurable bridge. Due to the reconfiguration of the transformer by two four ${\bf -}$ quadrant switches, the transformer exhibits three different effective turns ratios, which correspond to three output ranges. Moreover, in case of lower output voltage, the primary side is reconfigured as a half-bridge to further extend the output voltage range. The design of resonant tank parameters is less constrained by the voltage gain requirement. The switching frequency range in each mode can be squeezed close to the resonant frequency, which contributes to an improved soft switch performance. The operational principles, design considerations, and mode transition are analyzed. A 4 A rated prototype that converts 390 V input to a 60–450 V output is designed and tested to validate the concept. A smooth mode transition is achieved without transient issues. The design prototype demonstrates 97.50 $\%$ peak efficiency and good overall efficiency performance over this ultrawide output range.

The results of effective irradiation swelling in a wide range of burnup levels are numerically obtained for an inert matrix fuel, which are verified with DART model. The fission gas swelling of fuel particles is calculated with a mechanistic model, which depends on the external hydrostatic pressure. Additionally, irradiation and thermal creep effects are included in the inert matrix. The effects of matrix creep strains, external hydrostatic pressure and temperature on the effective irradiation swelling are investigated. The research results indicate that (1) the above effects are coupled with each other; (2) the matrix creep effects at high temperatures should be involved; and (3) ranged from 0 to 300MPa, a remarkable dependence of external hydrostatic pressure can be found. Furthermore, an explicit multi-variable mathematic model is established for the effective irradiation swelling, as a function of particle volume fraction, temperature, external hydrostatic pressure and fuel particle fission density, which can well reproduce the finite element results. The mathematic model for the current volume fraction of fuel particles can help establish other effective performance models.

This paper presents a lateral control strategy with kinematic state error model-based predictive control and extended state observer for unmanned ground vehicles. Firstly, we propose a circular arc prediction technique to calculate the state of the reference system. Then, inspired by the idea of active disturbance rejection control, an extended state observer is utilized to estimate the value of the total disturbance caused by modeling uncertainties, external disturbance, and other factors in order to compensate model error. Finally, we propose a lateral controller that combines model-based prediction with extended state observer through state feedback to achieve precise trajectory tracking. The performance of the proposed control strategy is demonstrated by a co-simulation between CarSim and MATLAB/Simulink.

Capillary electrophoresis (CE) is the primary methodology used in forensic DNA typing. Alleles of commonly used types of genetic markers could be separated and detected via CE based on dye color and migration time. Insertion/deletion (InDel) is an ideal genetic marker for forensic DNA analysis due to their abundance in the human genome, low mutation rate, availability of their allele types via CE, and elimination of stutter peaks. Moreover, Indels could be used as ancestry informative markers (AIMs) since allele frequencies of InDels is different among geographically separated populations. Several AI-InDels panels have been established based on CE platform to achieve the inter-continental populations distinction. However, improvements to differentiate intra-continental populations is few. In this study, twenty-one InDels with fixation index (FST ) >0.15 were selected and assembled into one AI-InDels panel. Using well-designed primers, those twenty-one InDels could be amplified successfully and genotyped on the CE platform accurately and completely. The panel showed a large FST distance distinction among the 10 Asian populations. Using clustering analysis, 10 Asian populations were classified into three subgroups: East Asian, Southeast Asian and South Asian subgroups. To evaluate the panel's capability in ancestry inference, a validation experiment was undertaken with 319 individuals from four geographically separated populations in China. Four Chinese populations were classified into different ancestry subgroups and 81.8% test individuals' ancestry could be inferred correctly. Our result showed development high ancestry informative InDels panel based on CE platform is a potential for individual ancestry inference among intra-continental populations. This article is protected by copyright. All rights reserved.

Performance evaluation and maintenance planning are gaining importance with ageing rail infrastructure and increasing demand on track safety and continuous availability. The discrete/point railway assets (e.g. bridges, level crossings) together with extended track sections constitute the main railway network infrastructure. The former has important implications in train safety, riding comfort and operating expenditures due to local intensified degradation and plays a role in effective network capacity due to their large quantity. The heterogeneity in asset features and operating environment also adds difficulties to efficient maintenance planning of multiple discrete assets. The current review screens the issue to level crossings, as little concern has been engaged to this asset type, and draws together different perspectives related to their maintenance management. The systems thinking approach is integrated and two levels of asset management (i.e. micro- and macro-level) are used to structure the synthesis, which are interdependent and synergistic. Two major approaches, namely, the mechanistic and data-driven modelling are synthesised. Both contribute to the maintenance knowledge and their comparisons are elaborated. Limitations in existing studies are identified and directions for future research are provided, aiming to contribute to a more refined ‘inspection and diagnosis’ process to properly capture the local track issues and move towards system-level maintenance approach for multiple level crossings.

Transition zones between railway tracks and bridge decks can cause higher dynamic impacts. A solution is smoothly changing the track stiffness by gradually mixing steel furnace slag into the stone ballast. A nominated bridge transition zone is divided into 5 blocks of 7 meters long, with the mixing percentages of 0%, 25%, 50%, 75% and 100%. The mechanical behaviors of furnace slag-ballast combinations (FS-BCs) were studied using experiments of shear strength test, Los Angles abrasion index and plate load test. Furthermore, the dynamic behavior of bridge transition zone with FS-BCs blocks was investigated using a field validated FEM model. Results show that the 100%, 75%, 50% and 25% furnace slag by weight of ballast can increase the shear strength and ballast layer bending modulus by 13%, 12%, 9% and 7% at speed of 300 km/h compared with those of the stone ballast. The FEM study shows that rail deflections are reduced about 20%, 14%, 21% and 16% at speed of 300 km/h corresponding to 100%, 75%, 50% and 25% FS-BCs and accelerations are significantly reduced as well as increasing FS content of each block in bridge transition zone so that a smooth bridge transition zone can be achieved.

Assembled in series with multistage, Electrical Submersible Pumps (ESP) are widely used in offshore petroleum production due to the high production rate and efficiency. The hydraulic performance of ESPs is subjected to the fluid viscosity. High oil viscosity leads to the degradation of ESP boosting pressure compared to the catalog curves under water flow. In this paper, the influence of fluid viscosity on the performance of a 14-stage radial-type ESP under varying operational conditions, e.g. rotational speeds 1800–3500 r/min, viscosities 25–520 cP, was investigated. Numerical simulations were conducted on the same ESP model using a commercial Computational Fluid Dynamics (CFD) software. The simulated average pump head is comparable to the corresponding experimental data under different viscosities and rotational speeds with less than ±20% prediction error. A mechanistic model accounting for the viscosity effect on ESP boosting pressure is proposed based on the Euler head in a centrifugal pump. A conceptual best-match flowrate QBM is introduced, at which the impeller outlet flow direction matches the designed flow direction. The recirculation losses caused by the mismatch of velocity triangles and other head losses resulted from the flow direction change, friction loss and leakage flow etc., are included in the model. The comparison of model predicted pump head versus experimental measurements under viscous fluid flow conditions demonstrates good agreement. The overall prediction error is less than ±10%.

Malware detection at scale in the Android realm is often carried out using machine learning techniques. State-of-the-art approaches such as DREBIN and MaMaDroid are reported to yield high detection rates when assessed against well-known datasets. Unfortunately, such datasets may include a large portion of duplicated samples, which may bias recorded experimental results and insights. In this article, we perform extensive experiments to measure the performance gap that occurs when datasets are de-duplicated. Our experimental results reveal that duplication in published datasets has a limited impact on supervised malware classification models. This observation contrasts with the finding of Allamanis on the general case of machine learning bias for big code. Our experiments, however, show that sample duplication more substantially affects unsupervised learning models (e.g., malware family clustering). Nevertheless, we argue that our fellow researchers and practitioners should always take sample duplication into consideration when performing machine-learning-based (via either supervised or unsupervised learning) Android malware detections, no matter how significant the impact might be.

The plate-type fuel assembly adopted in nuclear research reactor suffers from complicated effect induced by non-uniform irradiation, which might affect stress conditions, mechanical behaviors and thermal-hydraulic performance of the fuel assembly. This paper is the Part II work of a two-part study devoted to analyzing the complex unique mechanical deformation and thermal-hydraulic characteristics for the typical plate-type fuel assembly under irradiation effect, which is on the basis of developed and verified numerical thermal-fluid-structure coupling methodology under irradiation in Part I of this work. The mechanical deformation, thermal-hydraulic performance and Mises stress have been analyzed for the typical plate-type fuel assembly consisting of support plates under non-uniform irradiation. It was interesting to observe that: the plate-type fuel assembly including the fuel plates and support plates tended to bend towards the location with maximum fission rate; the hot spots in the fuel foil appeared at the location with maximum thickness increment; the maximum Mises stress of fuel foil was located at the adjacent location with the maximum plate thickness increment et al.

The plate-type fuel assembly adopted in nuclear research reactor suffers from complicated effect induced by non-uniform irradiation, which might affect its stress conditions, mechanical behavior and thermal-hydraulic performance. A reliable numerical method is of great importance to reveal the complex evolution of mechanical deformation, flow redistribution and temperature field for the plate-type fuel assembly under non-uniform irradiation. This paper is the first part of a two-part study developing the numerical methodology for the thermal-fluid-structure coupling behaviors of plate-type fuel assembly under irradiation. In this paper, the thermal-fluid-structure coupling methodology has been developed for plate-type fuel assembly under non-uniform irradiation condition by exchanging thermal-hydraulic and mechanical deformation parameters between Finite Element Model (FEM) software and Computational Fluid Dynamic (CFD) software with Mesh-based parallel Code Coupling Interface (MpCCI), which has been validated with experimental results. Based on the established methodology, the effects of non-uniform irradiation and fluid were discussed, which demonstrated that the maximum mechanical deformation with irradiation was dozens of times larger than that without irradiation and the hydraulic load on fuel plates due to differential pressure played a dominant role in the mechanical deformation.

More and more organizations move their data and workload to commercial cloud storage systems. However, the multiplexing and sharing of the resources in a cloud storage system present unpredictable data access latency to tenants, which may make online data-intensive applications unable to satisfy their deadline requirements. Thus, it is important for cloud storage systems to provide deadline guaranteed services. In this paper, to meet a current form of service level objective (SLO) that constrains the percentage of each tenant’s data access requests failing to meet its required deadline below a given threshold, we build a mathematical model to derive the upper bound of acceptable request arrival rate on each server. We then propose a Deadline Guaranteed storage service (called DGCloud ) that incorporates three basic algorithms. Its deadline-aware load balancing scheme redirects requests and creates replicas to release the excess load of each server beyond the derived upper bound. Its workload consolidation algorithm tries to maximally reduce servers while still satisfying the SLO to maximize the resource utilization. Its data placement optimization algorithm re-schedules the data placement to minimize the transmission cost of data replication. We further propose three enhancement methods to further improve the performance of DGCloud . A dynamic load balancing method allows an overloaded server to quickly offload its excess workload. A data request queue improvement method sets different priorities to the data responses in a server’s queue so that more requests can satisfy the SLO requirement. A wakeup server selection method selects a sleeping server that stores more popular data to wake up, which allows it to handle more data requests. Our trace-driven experiments in simulation and Amazon EC2 show the superior performance of DGCloud compared with previous methods in terms of deadline guarantees and system resource utilization, and the effectiveness of its individual algorithms.

Broadband transmitted wavefront measurement is a detection method that uses transmitted wavefronts at a few specific wavelengths though a function of Zernike coefficients and wavelength to predict other transmitted wavefronts at any wavelength within a certain range. This method is used when the designed wavelength of the interferometer and the detection wavelength are different. The function of the Zernike coefficients and wavelength can be expressed by the Conrady formula which can be used to describe a monotonic function curve or a function curve with an inflection point. Two methods, i.e., solving and fitting, can be used to determine the coefficients of the Conrady formula. Owing to the inevitable errors in the actual measurements, the fitting method is preferred to determine the coefficients of the Conrady formula. However, by analyzing the Conrady formula, it was found that the curve obtained by fitting the Conrady formula is a monotonic curve. This method cannot be used to obtain a curve with an inflection point or a slow-changing curve in the long waveband. In this paper, we propose an improved data fitting approach that transforms the Conrady formula into a polynomial formula to fit a given set of data for determining the Conrady formula coefficients. The correctness of the method was verified via simulations. Finally, the feasibility of the proposed method was verified by changing the light source and using the Fizeau interferometer to measure the transmitted wavefront of the doublet lens. To ascertain the feasibility of using visible light to predict the invisible light band, a near-infrared 1064 nm light source was added to the experimental set-up to broaden the range of the transmitted wavefront prediction waveband. Experimental results showed that the conversion polynomial fitting method can be used to obtain monotonic curves and the curve with an inflection point and a slow-changing curve in the long waveband, thereby mitigating the limitation of directly fitting the Conrady formula using a set of data points. Furthermore, using this method, we verified that the visible light can be used to predict the transmitted wavefront at any wavelength in the invisible light band. This observation is highly significant for the practical applications of the broadband transmitted wavefront measurement technique.

In this article, we introduce a vibration-powered sensing node (ViPSN), a programmable Internet-of-Things (IoT) platform for the development of vibration-powered or motion-powered sensing and transmitting systems. It leverages the exploitation and utilization of ambient vibration energy by using a piezoelectric transducer. The roles and relations of six necessary modules, including energy generation unit (EGU), energy transduction unit (ETU), energy enhancement unit (EEU), energy management unit (EMU), energy user unit (EUU), and edge demonstration unit (EDU) are discussed in detail. In particular, an enhanced EMU is proposed by making necessary complements to an extensively used off-the-shelf integrated circuit (IC) solution for piezoelectric transducers. It provides more comprehensive energy storage indicating signals, such that the sensing, computing, and transmitting tasks can be carried out more robustly by keeping a good awareness of the remaining energy. Owing to the enhanced EMU design, vibration energy in various forms, such as intermittent and transient ones, can be more effectively harvested and utilized. The performance of ViPSN is evaluated, in terms of its lifetime and Quality of Service (QoS), under different vibration scenarios. The inclusive design and affiliated opensource project of ViPSN help build a new ecosystem for the research and development of vibration- or motion-powered IoT systems.

As a two-dimensional material, molybdenum disulfide (MoS2) exhibits great potential to replace metal platinum-based catalysts for hydrogen evolution reaction (HER). However, poor electrical conductivity and low intrinsic activity of MoS2 limit its application in electrocatalysis. Herein, we prepare a defective-MoS2/rGO heterostructures material containing 1T phase MoS2 and evaluate its HER performance. The experimental results shown that defective-MoS2/rGO heterostructures exhibits outstanding HER performance with a low overpotential at 154.77 mV affording the current density of 10 mA cm−2 and small Tafel slope of 56.17 mV dec−1. The unique HER performance of as-prepared catalyst can be attributed to the presence of 1T phase MoS2, which has more active sites and higher intrinsic conductivity. While the defects of as-prepared catalyst fully expose the active sites and further improve catalytic activity. Furthermore, the interaction between MoS2 and rGO heterostructures can accelerate electron transfer kinetics, and effectively ensure that the obtained catalyst displays excellent conductivity and structural stability, so the as-prepared catalyst also exhibits outstanding electrochemical cycling stability. This work provides a feasible and effective method for preparation of defective-MoS2/rGO heterostructures, which also supplies a new strategy for designing of highly active and conductive catalysts for HER.

Dual-active-bridge (DAB) converter based on single-phase shift (SPS) modulation is commonly used in energy storage systems. However, if the normalized voltage gain deviates from unity, the zero-voltage-switching (ZVS) feature and efficiency of the DAB converter deteriorate. To overcome this challenge, this article proposes a hybrid-bridge and hybrid modulation-based DAB converter adapted to a wide voltage range. The primary-side hybrid bridge operates in an intermediate state between the full bridge and the half bridge. Asymmetrical pulsewidth modulation (APWM) is introduced to regulate the dc bias across the blocking capacitor in a continuous manner. Due to the synergy between the hybrid-bridge structure and hybrid modulation scheme, a general voltage match between the energy storage unit and the high-voltage bus is always achieved. Moreover, the ZVS range is extended and the circulating current is well suppressed. Therefore, efficiency is optimized over the wide voltage range. The operational principles, circuit modeling, and design considerations are detailed. A 500-W converter prototype, linking a 100–200-V energy storage unit and a 300-V dc bus, is designed and tested to validate the concept. A 97.9% peak efficiency and good overall efficiency over the wide voltage range are reported.

Oblique photogrammetry with multiple cameras onboard unmanned aerial vehicle (UAV) has been widely applied in the construction of photorealistic three-dimensional (3-D) urban models, but how to obtain the optimal building facade texture images (BFTIs) from the abundant oblique images has been a challenging problem. This article presents an optimization method for selection of BFTIs from the image flows acquired by five oblique cameras onboard UAV. The proposed method uses multiobjective functions, which consists of the smallest occlusion of the BFTI and the largest facade texture area, to select the optimal BFTIs. Geometric correction, color equalization, and texture repairment are also considered for correction of BFTI’s distortions, uneven color, and occlusion by other objects such as trees. Visual C++ and OpenGL under the Windows Operating System are used to implement the proposed methods and algorithms. The proposed method is verified using 49 800 oblique images collected by five cameras onboard the Matrice 600 Pro (M600 Pro) UAV system over Dongguan Street, in the City of Ji’nan, Shandong, China. To restore the partially occluded textures, different thresholds and different sizes of windows are experimented, and a template window of $200\times200$ pixels2 is recommended. With the proposed method, 2740 BFTIs are extracted from 49 800 oblique images. As compared with the Pix4Dmapper and Smart 3-D method, it can be concluded that the optimal texture can be selected from the image flow acquired by multiple cameras onboard UAV and the approximately 95% memory occupied by the original BFTIs is reduced.

Conventional frequency modulated LLC topology is unsuitable for ultrawide voltage range applications and suffers from poor voltage regulation performance at light load conditions. To cope with those issues, this article proposes a novel two-phase dual LLC resonant converter. The primary side of the proposed converter is two paralleled half-bridges LLC , and the transformers’ secondary sides are in reverse series with shared full bridge rectifier. Both resonant tanks are driven by two fixed-frequency square waves, whose frequencies are always tuned at the optimal resonant frequency. A phase shift is introduced between those two square waves to regulate the output voltage. The proposed topology demonstrates good voltage regulation performance, which is weakly dependent on the load condition. Zero-voltage switching and zero-current switching are well realized on the power mosfet s and diodes in a wide range. A 1-kW rated laboratory prototype is designed to convert 390 V input to 10–420 V output. The prototype demonstrates a 98.1% peak efficiency and good voltage regulation capability. The experimental results agree well with the theoretical analysis.

With the rapid development of electronic technology, the demand for thermal management materials is increasing continuously. Recent years graphene paper is considered as a potential material to replace the traditional graphitized polyimide film. Although the current route to graphene paper can achieve a high thermal conductivity, the extremely high energy consumption in graphitization procedure and severe heavy metal contamination limit the application of graphene paper. Here we develop a high-efficiency, low-energy cost, and inexpensive technology to produce graphene paper in large quantities. Without graphitization, the thermal conductivity of this graphene laminated film can reach 975 W m−1 K−1 when the thickness of film is 65 μm. Based on this easy-operated technology, we have already completed the pilot plant test, attained capacity of 3 kg graphene per reactor in 8 h and 800 mm × 100 m of graphene film each roll which was continuously and macroscopically assembled on our self-made equipment.

Hyperspectral image (HSI) classification has attracted much attention in the field of remote sensing. However, the lack of sufficient labeled training samples is a huge challenge for HSI classification. To face this challenge, we propose a semisupervised HSI classification method based on graph convolutional broad network (GCBN). First, to avoid the underfitting problem caused by the insufficient linear sparse feature representation ability of broad learning system (BLS), graph convolution operation is applied to extract nonlinear and discriminative spectral-spatial features from the original HSI to replace the linear mapping features in the traditional BLS. Second, to solve the problem of insufficient model classification ability caused by limited labeled samples, the combinatorial average method (CAM) is proposed to use valuable paired samples to generate sample expansion set for GCBN model training. Third, BLS is used to perform broad expansion on spectral-spatial features extracted by GCN and extended by CAM, which further enhances the feature representation ability. Finally, the output weights can be easily calculated by the ridge regression theory. Experimental results on three real HSI datasets demonstrate the effectiveness of our proposed GCBN.

Hydrothermal co-liquefaction of lignite (L) and lignocellulosic biomass represented by cornstalk (CS) and pinewood sawdust (PW) was investigated in this work under various conditions in the presenc...

The production of counterfeit money has a long history. It refers to the creation of imitation currency that is produced without the legal sanction of government. With the growth of the cryptocurrency ecosystem, there is expanding evidence that counterfeit cryptocurrency has also appeared. In this paper, we empirically explore the presence of counterfeit cryptocurrencies on Ethereum and measure their impact. By analyzing over 190K ERC-20 tokens (or cryptocurrencies) on Ethereum, we have identified 2, 117 counterfeit tokens that target 94 of the 100 most popular cryptocurrencies. We perform an end-to-end characterization of the counterfeit token ecosystem, including their popularity, creators and holders, fraudulent behaviors and advertising channels. Through this, we have identified two types of scams related to counterfeit tokens and devised techniques to identify such scams. We observe that over 7,104 victims were deceived in these scams, and the overall financial loss sums to a minimum of $ 17 million (74,271.7 ETH). Our findings demonstrate the urgency to identify counterfeit cryptocurrencies and mitigate this threat., accepted to SIGMETRICS 2021

The rapid pressure swing adsorption (RPSA) technology has been widely used for applications including portable oxygen generators due to high O2 productivities and low bed size factors (BSF, total amount of adsorbent per ton of O2 produced per day, kg/TPDO2). The improvement of RPSA process has been a key issue for efficient O2 production in terms of its generally lower O2 recovery as compared to other processes. In this work, a dual-column RPSA oxygen production system with an intermittent purge step (intermittently switching between purge and interruption) was designed to investigate the effects of interruption frequency (the number of interruptions during a purge step) and times on the O2 recovery, purity, productivity and BSF. Experimental results show the improvement on O2 production performance using the intermittent purge step in comparison to conventional continuous purge step. Under the optimized interruption frequency of 2 and time of 0.3 s, the O2 recovery, purity and productivity were increased from 36 to 39.2%, 89.5 to 93%, and 6.24 to 6.49 mmol/kg/s, respectively, while the BSF was decreased from 57.94 to 55.75 kg/TPDO2.

Development of a functional nerve conduit to replace autografts remains a significant challenge particularly considering the compositional complexity and structural hierarchy of native peripheral nerves. In the present study, a multiscale strategy was adopted to fabricate 3D biomimetic nerve conduit from Antheraea pernyi silk fibroin (ApF)/(Poly(L-lactic acid-co-caprolactone)) (PLCL)/graphene oxide (GO) (ApF/PLCL/GO) nanofibers via nanofiber dispersion, template-molding, freeze-drying and crosslinking. The resultant conduits exhibit parallel multichannels (ϕ = 125 µm) surrounded by biomimetic fibrous fragments with tailored degradation rate and improved mechanical properties in comparison with the scaffold without GO. In vitro studies showed that such 3D biomimetic nerve scaffolds had the ability to offer an effective guiding interface for neuronal cell growth. Furthermore, these conduits showed a similarity to autografts in vivo repairing sciatic nerve defects based on a series of analysis (walking track, triceps weight, morphogenesis, vascularization, axonal regrowth and myelination). The conduits almost completely degraded within 12 weeks. These findings demonstrate that the 3D hierarchical nerve guidance conduit (NGC) with fascicle-like structure have great potential for peripheral nerve repair.

A binary direct Z-scheme LaNiO3/g-C3N4 nanocomposite photocatalyst consisted with LaNiO3 nanoparticles and g-C3N4 nanosheets was successfully synthesized by means of mechanical mixing and solvothermal methods in order to improve the photocatalytic water splitting activity. The as-prepared materials were characterized by powder X-ray diffraction (XRD), Scanning Electron microscope (SEM), Transmission Electron microscope (TEM), X-ray photoelectron spectroscope (XPS), Fourier Transform Infrared Spectroscopy (FT-IR) and N2 adsorption–desorption experiments, respectively, demonstrating the formation of interfacial interaction and heterogeneous structure in LaNiO3/g-C3N4 nanocomposites. Under UV-light irradiation, the LaNiO3/g-C3N4 samples which without the addition of any noble metal as co-catalyst behaved enhanced photocatalytic water splitting activity compared with pure LaNiO3 and g-C3N4, owing to the Z-scheme charge carrier transfer pathway. Especially, the LaNiO3/70%g-C3N4 nanocomposite reach an optimal yield of up to 3392.50 µmol g−1 in 5 h and held a maximum H2 evolution rate of 678.5 µmol h−1 g−1 that was 5 times higher than that of pure LaNiO3.

The effects of Mn content and grain size on the hydrogen embrittlement resistance of face-centered cubic (FCC) CrCoFeMnNi high-entropy alloys were examined using tensile testing at an initial strain rate of 10−4 s−1. The most important finding of this study was that the combined effect of Mn removal and grain refinement provided nearly complete resistance to hydrogen embrittlement with over 800 MPa tensile strength in FCC high-entropy alloys, even after 100 MPa hydrogen gas charging.

The dramatic advances in flexible/wearable electronics have garnered great attention for touch sensors for practical applications in human health monitoring and human–machine interfaces. Self-powered triboelectric tactile sensors with high sensitivity, reduced crosstalk, and simple processing routes are highly desirable. Herein, we introduce a facile and low-cost fabrication approach for a metal-electrode free, fully integrated, flexible, and self-powered triboelectric tactile sensor array with 8-by-8 sensor units. Through the height difference between the sensor units and interconnect electrodes, the crosstalk derived from the electrodes has been successfully suppressed with no additional shielding layers. The tactile sensor array shows a remarkable sensitivity of 0.063 V kPa–1 with a linear range from 5 to 50 kPa, which covers a broad range of testing objects. Furthermore, due to the advanced mechanical design, the flexible sensor array exhibits great capability of pressure sensing even under a curved state. The voltage responses from the pattern mapping by finger touching demonstrate the uniformity of the sensor array. Finally, real-time tactile sensing associated with light-emitting diode (LED) array lighting demonstrates the potential application of the sensor array in position tracking, self-powered touch screens, human–machine interfaces and many others. A fully integrated soft tactile sensor array (ISTSA) that is self-powered and without metal electrodes has been developed using a low-cost, easily performed fabrication process. A sensor array is a group of sensors used for collecting and processing electromagnetic signals, and arrays of tactile sensors have recently attracted substantial attention with the growth of wearable electronics and application in health monitoring and human-machine interfaces. A team headed by Yunlong Zi at The Chinese University of Hong Kong succeeded in developing an ISTSA with remarkable sensitivity. The ISTSA is so flexible that it exhibits excellent pressure sensing even in a curved state. The authors conducted real-time tactile sensing with LED lighting and finger touching, and they believe their ISTSA has considerable potential for application in such areas as position tracking, self-powered touch screens, and wearable electronics.

Purpose Fixed-dose combination glecaprevir (GLE) 300 mg + pibrentasvir (PIB) 120 mg is an orally administered once daily antiviral regimen approved for the treatment of hepatitis C virus (HCV) infection. The objective of this study was to evaluate the potential for cardiac repolarization following GLE + PIB administration in healthy adults. Methods This placebo- and active-controlled, randomized, single-dose, 4-period, 4-sequence crossover study enrolled 48 healthy subjects. The doses of GLE 400 mg + PIB 120 mg were selected to provide exposures comparable to those with the doses that are therapeutic in the HCV-infected population, GLE 300 mg + PIB 120 mg. The doses of GLE 600 mg + PIB 240 mg were selected to provide supratherapeutic exposures without exceeding the exposures of the GLE + PIB maximal tolerated doses. Moxifloxacin 400 mg (active control/open label) was used for confirming the sensitivity of the ECG assay in detecting QTc prolongation. Time-matched plasma concentrations and triplicate ECGs were obtained on treatment days −1 and 1. The primary end point was time-matched, placebo-corrected, baseline-adjusted Fridericia-corrected QT interval (ΔΔQTcF). Pharmacokinetic–pharmacodynamic analyses characterized the relationship between GLE and PIB plasma concentrations and ΔΔQTcF using a linear regression model and linear mixed-effects model. Findings from categorical analyses of ECG-interval data were also summarized. Tolerability was evaluated through adverse-events monitoring, physical examination including vital sign measurements, ECGs, and laboratory tests. Findings A total of 48 subjects (22 women [46%], 26 men [54%]), were enrolled in the study, and 47 subjects completed all 4 periods. None of the subjects had a change from baseline in QTcF interval of >30 msec or an absolute QTcF interval of >450 msec. Peak ΔΔQTcF values observed at 5 h postdose (Tmax) were 2.9 msec (upper 95% confidence limit, 4.9 msec) with the therapeutic dose and 3.1 msec (upper 95% confidence limit, 5.1 msec) with the supratherapeutic dose, with both upper 95% confidence limits well below the 10-msec threshold. Assay sensitivity was confirmed by peak ΔΔQTcF in the positive control (12.8 ms at 2 h postdose). No statistically significant GLE or PIB concentration-dependent effects on ΔΔQTcF were observed. Headache and skin irritation from ECG electrodes were the most commonly reported AEs. No clinically significant vital sign measurements, ECG findings, or laboratory measurements were observed. There were no patterns of T- and U-wave morphologic abnormalities. Implications The fixed-dose combination regimen of GLE/PIB does not prolong the QTc interval. ClinicalTrials.gov identifier.

Multilevel inverter configurations are a suitable candidate for medium and high power applications. This study presents a new one-capacitor-based five-level (2 V dc , V dc , 0, − V dc , − 2 V dc ) boost multilevel inverter. The single-phase version of the proposed formation has one dc-source, eight switches and one capacitor. To provide boosting ability, the inverter is operating based on charge-pump theory, where the capacitor is charging in parallel and discharging in series connections to provide a higher output voltage. The proposed configuration requires simple control tasks, and for this purpose, level-shift pulse width modulation strategy, where the reference signal is compared with four carriers, is implemented to drive the switches and generates the required pulses pattern. The developed inverter has some distinct features like the usage of only one dc-source and one-capacitor, compact size, simple control requirements and boosting ability. The system is simulated with MATLAB/Simulink and a hardware prototype is developed to verify the performance of the developed five-level configuration. The results show that the developed five-level multilevel inverter reaches the expected performance

Cancer immunotherapy as a novel cancer therapeutic strategy has shown enormous promise. However, the immunosuppressive tumor microenvironment (ITM) is a primary obstacle. Tumor-associated macrophages (TAMs) as a major component of immune cells in a tumor microenvironment are generally polarized to the M2 phenotype that not only accelerates tumor growth but also influences the infiltration of lymphocytes and leads to immunosuppression. Thus, rebuilding ITM by re-educating TAMs and increasing infiltration of lymphocytes is a promising strategy. Herein, gadofullerene (GF-Ala) nanoparticles are demonstrated to reprogram TAMs to M1-like and increase the infiltration of cytotoxic T lymphocytes (CTLs), achieving effective inhibition of tumor growth. Notably, the modulation of ITM by GF-Ala promotes the anticancer efficacy of anti-PD-L1 immune checkpoint inhibitor, achieving superior synergistic treatment. Additionally, GF-Ala nanoparticles can be mostly excreted from the body and cause no obvious toxicity. Together, this study provides an effective immunomodulation strategy using gadofullerene nanoparticles by rebuilding ITM and synergizing immune checkpoint blockade therapy.

In battery/ultracapacitor (UC) hybrid energy storage systems (HESS), sizing and energy management strategies are crucial, which determine the system cost and performance. However, research on these two problems in a coupled manner for plug-in electric vehicles is still immature. This article aims at resolving this issue in the perspective of minimizing the average operating cost. Both manufacturing cost and system end-of-life timing are incorporated. A quantitative battery degradation model is employed to evaluate the battery dynamic capacity loss and cycle life. Dynamic programming algorithm is then deployed to achieve optimal power distribution between battery and UC. Furthermore, the power management and HESS optimal sizing strategies are unified into a single cost-minimization problem. Combining those efforts, the optimal size of the HESS with minimized average operating cost is solved by simulated annealing method. Optimization results illustrate that a minimum cost of 15.52 USD is achieved with 72 UC cells and 7100 battery cells. A large set of simulation data has proved the optimality of the optimization results. Compared with the battery-only solution, the proposed solution demonstrates 11.9% cost reduction and 21.7% battery cycle life extension under the Urban Dynamometer Driving Schedule. Moreover, the temperature rise of the battery is reduced by 31.1%. Finally, based on the optimal results, the energy management strategy is extended to fit real-time applications by utilizing Markov chain and stochastic dynamic programming.

Secondary electrocaloric effect (ECE) arising from piezoelectricity combined with crystal thermal expansion was often overlooked in ECE studies of ferroelectric ceramics. This work mainly evaluated the primary ECE (ΔTECE) and secondary ECE (∆T2) of eco-friendly BaSnxTi1-xO3 (BSnT100x, 0

In this paper, an LLC type converter with two interleaved pulsewidth modulation (PWM) rectifiers is proposed. Compared with the conventional LLC converter, it achieves a wide voltage regulation range independent of load. In the proposed structure, each secondary-side PWM rectifier can operate individually. With the interleaving technique and shared primary-side switching network, the circuit secondary-side current stress is halved and the primary-side current stress is largely reduced. Besides, the filter capacitor requirement is reduced. Therefore, the proposed structure is a good option for medium/high power wide output range applications. The symmetrical LLC resonant tanks always operate at the resonant frequency, which marks the optimal operation point of the LLC resonant tank. Therefore, the conduction loss is effectively mitigated. In the proposed converter, zero-voltage turning- on (ZVS) of the primary-side MOSFETs can be ensured and is independent of the load. Moreover, the turning- off currents of the primary-side MOSFETs are small and are also load independent. This brings the benefits of minimized circulating current and negligible turning- off loss and no MOSFET turning- off voltage spike. The secondary-side auxiliary MOSFETs turn- on with ZVS and rectifying diodes turn- off with limited di / dt. Topological analysis and experimental results of a 1.3 kW/100 kHz prototype generating 230–440 V output from 390-V input are presented. The prototype demonstrates 97.31% peak efficiency and good performance over a wide output range.

Liquid crystal (LC), a characteristic substance of biofilms, has been reported to positively affect cell affinity. To better combine and utilize the properties of an LC and the advantages of polyurethane (PU) elastomers, the three-dimensional printing (3DP) molding technology and the simple soaking-swelling blending technology were used to construct PU/LC 3D composite scaffolds, and the compressive strength, porosity, hydrophilicity, and in vitro cell experiments of the scaffolds were initially discussed. The results indicated that the newly developed PU/LC 3D composite scaffolds exhibited an LC state; the addition of an LC did not change the porosity after swelling while maintaining a high porosity; the compressive strength of the composite scaffolds decreased while still maintaining high mechanical properties and enhancing hydrophilicity. At the same time, it could improve the cell affinity on the surface of the material, which was beneficial to increase the cell adhesion rate and cell activity, promote the osteogenic differentiation of human mesenchymal stem cells grown on the materials, and improve the alkaline phosphatase activity, calcium nodules, and the expression of related osteogenic genes and proteins. These results demonstrated potential applications of PU/LC composite scaffolds in repairing or regeneration of bone tissue engineering.

Though deep learning methods in Person Re-ID have increased its performance, the field is still confronted with great challenges such as pedestrian misalignment due to the inferior pedestrian detector. To solve such problems, we propose Curriculum Enhanced Supervised Attention Network (CE-SAN): Firstly, an attention module is trained under supervision, which helps the network further emphasize the key information and associate the local and global branch together, leading to a better exploitation of the discriminative features. Secondly, a curriculum design is adopted to divide the dataset into subsets according to the distribution density of the training samples, enabling the network to learn gradually to increase the capability. Moreover, The CE-SAN is easy to be plugged in most of the backbones with high generalization ability. To prove the CE-SAN's superiority, experiments are conducted on three datasets, CE-SAN achieves competitive performance with the state-of-the-arts on Market-1501 and DukeMTMC-reID. Particularly, on the most challenging MSMT17, it outperforms the state-of-the-art methods by 5.2 $\%$ in Rank-1 and 6.5 $\%$ in mAP.

The high strength and high hard metal materials such as nickel-based superalloy have been widely used because of their excellent properties. If the gradient nanostructures are prepared on their surfaces, their properties will be further improved and their application will be expanded. In this paper, a coupled mechanical ultrasonic-electric pulse (CMUEP) treatment method is presented and its special pulse power source with high instantaneous energy density is developed. The power supply includes main circuit, gate turn-off thyristor (GTO) control circuit, switch control circuit, display circuit, etc. The CMUEP treatment of nickel-based superalloy is carried out by using this power source. The results show that grains with the average diameter of 25.8nm are prepared on Inconel 718 surface, which can further improve the properties of the high strength and high hard metal materials and broaden their application.

Hierarchical linear control scheme is widely used in ac microgrids. However, its transient response is slow and parameter tuning is time-consuming. Finite Control Set-Model Predictive Control (FCS-MPC) strategy has desired dynamic performance. Nevertheless, it requires an additional sensor to measure the inductor current. This article aims to mitigate these problems by introducing an improved FCS-MPC strategy for paralleled Voltage Source Inverters (VSIs). A capacitor current estimator is employed to reduce the extra current sensor in each VSI. The proposed control scheme consists of two loops: voltage reference generation loop and voltage tracking loop. The voltage reference generation loop achieves accurate load power sharing using virtual impedance-based droop control. Thus, communication is unnecessary among parallel VSIs. The voltage tracking loop utilizes a modified FCS-MPC block with capacitor current estimator to regulate the VSI output voltage. In order to verify the concept of the proposed control strategy, an ac microgrid consisting of two paralleled VSIs is implemented in dSPACE DS1202 hardware-in-the-loop platform. Then a single VSI hardware prototype is implemented and tested experimentally. The proposed method has the merits of good extensibility, low system cost and compact structure. Its steady-state performance is competitive with hierarchical linear control, while the transient response is significantly improved.

In this work, (Ba1−xSrx)Zr0.1Ti0.9O3 (BSZTx, x = 0, 0.15, 0.25 and 0.35) thin films were successfully deposited on La0.7Sr0.3MnO3 (LSMO)-coated (001) SrTiO3 (STO) single crystal substrates using laser molecular beam epitaxy. The BSZTx thin films with compositions of x = 0 and 0.15 display an inverse electrocaloric effect (ECE) with a maximum adiabatic temperature change of ΔT ∼ −10 K under 1500 kV cm−1, while a large positive ΔT amounting to ∼13 K is discovered in the strontium rich composition, i.e. x = 0.35. For the composition of x = 0.25 where weak ECE (|ΔT| < 2 K) is discovered, an energy storage density of 15.5 J cm−3 with an efficiency of 69.8% is observed in the temperature range of 303–413 K. The composition-tunable electrocaloric effect and large energy storage density with excellent thermal stability in strontium modified Ba(Zr0.1Ti0.9)O3 thin films are ascribed to the synergistic effects of different dynamics of polar nano-regions (PNRs) and conformed defect dipoles under large electric fields at elevated temperatures. This work will facilitate the development of novel solid-state cooling devices and provide a design route for high energy storage density devices.

Hyperspectral images (HSI) are widely applied in numerous fields for their rich spatial and spectral information. However, in these applications, we always face the situation that the available labeled samples are limited or absent. Therefore, we propose an HSI classification method based on domain adaptation broad learning (DABL). First, according to the importance of the marginal and conditional distributions, the maximum mean discrepancy is used in mapped features to adapt these distributions between source and target domains. Meanwhile the manifold regularization is added to maintain the manifold structure of the input HSI data. Second, to further reduce the distribution difference and maintain manifold structure, the domain adaptation and manifold regularization are added to the output layer of DABL. Finally, the output weights can be easily calculated by the ridge regression theory. Experimental results on three real HSI datasets demonstrate the effectiveness of our proposed DABL.

Exploiting relays in millimeter wave (mmWave) systems is an effective way to extend the communication coverage and overcome the blockage problem. This paper comprehensively studies secure transmissions in mmWave decode-and-forward (DF) relay systems. Depending on the overlapped resolvable paths between the main channel and the wiretap channel in each transmission stage, we consider three eavesdropping scenarios, namely two-stage eavesdropping (TSE), single-stage eavesdropping (SSE) and no eavesdropping (NE). We investigate secrecy performance and optimal parameter design of these eavesdropping scenarios under the same codeword transmission (SCT) scheme and the different codewords transmission (DCT) scheme, where source and relay utilize same codeword or different codewords. Specifically, we derive closed-form expressions for connection probability and secrecy outage probability, and then give solution to the secrecy throughput maximization problem. Furthermore, we investigate the effectiveness of the artificial noise (AN) by evaluating the secrecy performance of AN assisted transmissions. Numerical results are provided to verify our theoretical analysis. Our results give insights into the secure transmission scheme selection and the impact of various parameters, such as number of antennas, power allocation between source and relay, number of overlapped paths, and distances between different nodes, on the secrecy performance of the mmWave relay system.

The rapid growth of cloud computing in cloud datacenters in recent decades greatly increases the brown energy consumption in datacenters, and hence significant increase of carbon emission that negatively impacts on the environment as well as the monetary cost. More and more cloud service providers are adopting renewable energy as the energy supply to offset the consumption of brown energy. Meanwhile, an increasing number of renewable energy generators have been built to meet the needs. However, the instability of the renewable energy cannot guarantee the support to the datacenter and the energy competition of different datacenters may lead to datacenter energy outage. In this paper, we focus on the problem of how to match different renewable energy generators to the datacenters from different cloud providers to minimize the carbon emission, monetary cost, and service level objective (SLO) violation due to renewable energy shortage. The challenges here are that the datacenters may compete in energy requesting, the renewable energy generation is not stable and the decision should be made quickly. There have been no previous efforts devoting to this problem. To solve the problem, we first test several machine learning techniques on long-term prediction accuracy on renewable energy generation and energy demand using real traces and identify SARIMA for the prediction. We then propose a multi-agent reinforcement learning based method (MARL) for each datacenter to determine how much renewable energy to request from each generator based on the predicted results. We also propose a deadline guaranteed job postponement method (DGJP) to postpone executing unurgent jobs upon insufficient renewable energy supply. The trace-driven experiments show that MARL outperforms other methods by increasing up to 35% SLO satisfaction ratio, and reducing up to 19% (0.33 billion dollars in 90 days) total monetary cost and 33% total carbon emission, and DGJP further improves the performance.

Image segmentation plays a significant role in remote sensing image processing. Among numerous segmentation algorithms, the region-merging segmentation algorithm is widely used due to its well-organized structure and outstanding results. Many merging criteria (MC) were designed to improve the accuracy of region-merging segmentation, but each MC has its own shortcomings, which can cause segmentation errors. Segmentation accuracy can be improved by referring to the segmentation results. To achieve this, an approach for detecting and correcting region-merging image segmentation errors is proposed, and then an iterative optimization model is established. The main contributions of this paper are as follows: (1) The conflict types of matching segment pairs are divided into scale-expression conflict (SEC) and region-ownership conflict (ROC), and ROC is more suitable for optimization. (2) An equal-scale local evaluation method was designed to quantify the optimization potential of ROC. (3) A regional anchoring strategy is proposed to preserve the results of the previous iteration optimization. Three QuickBird satellite images of different land-cover types were used for validating the proposed approach. Both unsupervised and supervised evaluation results prove that the proposed approach can effectively improve segmentation accuracy. All explicit and implicit optimization modes are concluded, which further illustrate the stability of the proposed approach.

Aiming at understanding the phase distribution characteristics and developing the transition criterion from wall-peak to core-peak phase distribution in a rod bundle channel, air–water two-phase flow experiments were conducted in 5 × 5 rod bundles in the Interfacial Evolution Research Facility at Chongqing University (IERFC). Based on the experimental data, the influences of gas velocity, liquid velocity, mixing vane spacer grid (MVSG), and geometrical size on phase distribution have been analyzed in detail. With the increasing superficial gas velocity and decreasing liquid velocity, the wall-peak phase distribution turned to core-peak. The wall-peak phase distribution was enhanced by an MVSG, and the transition from the transitional phase distribution to the wall-peak phase distribution appeared when the air–water mixture flowed through the MVSG. The gap size was the key factor for the transition of phase distribution in rod bundles. Moreover, the transition criterion from wall-peak to core-peak phase distribution was developed based on present experimental data and the data in the literature, which was also verified based on the limited data. More experiments were recommended to focus on the detailed phase distribution in the rod bundle channel with different geometrical sizes.

As the COVID-19 pandemic emerged in early 2020, a number of malicious actors have started capitalizing the topic. Although a few media reports mentioned the existence of coronavirus-themed mobile malware, the research community lacks the understanding of the landscape of the coronavirus-themed mobile malware. In this paper, we present the first systematic study of coronavirus-themed Android malware. We first make efforts to create a daily growing COVID-19 themed mobile app dataset, which contains 4,322 COVID-19 themed apk samples (2,500 unique apps) and 611 potential malware samples (370 unique malicious apps) by the time of mid-November, 2020. We then present an analysis of them from multiple perspectives including trends and statistics, installation methods, malicious behaviors and malicious actors behind them. We observe that the COVID-19 themed apps as well as malicious ones began to flourish almost as soon as the pandemic broke out worldwide. Most malicious apps are camouflaged as benign apps using the same app identifiers (e.g., app name, package name and app icon). Their main purposes are either stealing users’ private information or making profit by using tricks like phishing and extortion. Furthermore, only a quarter of the COVID-19 malware creators are habitual developers who have been active for a long time, while 75% of them are newcomers in this pandemic. The malicious developers are mainly located in the US, mostly targeting countries including English-speaking countries, China, Arabic countries and Europe. To facilitate future research, we have publicly released all the well-labelled COVID-19 themed apps (and malware) to the research community. Till now, over 30 research institutes around the world have requested our dataset for COVID-19 themed research.

Elpasolite halides scintillation crystals have been proven to be very important materials for X-ray and γ-ray detector applications. The crystals of Cs2KLaCl6:4% Ce (CKLC) and Cs2KCeCl6 (CKCC) belong to novel scintillation of the Chloro-elpasolite crystal family. In this paper, the crystal growth of CKLC and CKCC crystals using the vertical Bridgman techniques were reported. The PXRD patterns showing both crystals have a cubic crystal structure. Both crystals have similar photoluminescence excitation and emission spectra, the fluorescence decay time of CKLC and CKCC crystals were about 49.7 and 33.8 ns. The energy resolution under the excitation of 662 keV γ-rays from a 137Cs source were found to be 6.6% and 5.2% (FWHM), respectively. The scintillation decay times of CKLC crystal were τ1 = 127 ns (33%) and τ2 = 1617 ns (67%), while that of CKCC crystal were τ1 = 2.86 ns (5%) and τ2 = 81 ns (95%).

In high-voltage bus-based photovoltaic systems, a power electronic interface is required to manage the power flow in between the photovoltaic (PV) panel, battery, and the high-voltage dc bus. In this paper, a novel three-port dc/dc topology is proposed for this application. Pulsewidth and phase-shift offer two degrees of freedom to effectively regulate the power flows. On the primary side, the input current ripple is reduced due to the interleaved structure. This avoids the usage of the bulky electrolytic capacitors on the PV terminal. On the secondary side, a voltage sixfolder rectifier is employed to boost the step-up ratio. This reduces the transformer's secondary-side turns number. Moreover, the voltage stresses of secondary-side mosfet s and diodes are reduced to one-third of the output voltage. Zero-voltage switching and zero-current switching are realized among all power mosfet s and diodes, respectively, and in an extended range. A 500-W converter prototype, linking a battery pack, a PV panel, and a 760 V dc bus, is designed and tested to verify the proof-of-concept. Both the circuit functionality and theoretical analysis are validated by the experimental results.

High-order compensation provides more design freedom for inductive power transfer systems and can help improve output voltage/current controllability. This paper develops a simplified decomposition and synthesis method for high-order-compensated inductive power transfer systems. It can achieve load-independent (LI) output under coupling variation, and easily fulfill the various charging requirements, such as constant voltage or constant current. The coupling independent resonance is ensured by using the induced source model, and the whole resonant tank is effectively decomposed as three parts. The power transfer characteristics are discussed for each part, and the requirements for LI output and zero phase angle (ZPA) operation are combined to generate the compensation candidates for both sides. Two families of topologies are synthesized for four kinds of conversions, i.e., voltage to voltage, voltage to current, current to voltage, and current to current. Meanwhile, the proposed method dramatically simplifies the evaluation for the influence of the coil equivalent series resistors on the transfer function and efficiency. These resistor-caused effects are quite different for two families of topologies. Finally, a 6.78-MHz system with 10-W output is designed to verify the difference between two-family topologies.

Magnetocaloric effects, because of their large entropy change, have been demonstrated to potentially revolutionize the solid-state cooling devices with high energy efficiency and environmental friendliness. However, the requirement of applying large magnetic fields obstructs the minimization of cooling devices. Here, we investigated electric-field-control magnetocaloric effects in magnetoelectric heterostructures by combining thermodynamic modelling and first-principle calculations. Based on strain-mediated mechanism, it is demonstrated that the interface strain of ferroelectric film under the electric field can tune the magnetic transition temperature from ferromagnetic to antiferromagnetic phases with 5 K shift under a small electric field of 0.1 MV/m and a giant entropy change of 14.9 J/(kg·K). In addition, we propose a potential multicaloric device including magnetocaloric and elastocaloric effects with high cooling efficiency based on magnetic-elastic-electric coupling phase transformations. The present study therefore contributes to the understanding of electric-field-control magnetocaloric cooling and provides guidance for experiments to design high efficiency and low-power consumption multicaloric cooling devices using magnetoelectric heterostructures.