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Fe[Fe(CN)6] (FeHCF) is considered a promising material for capacitive deionization–desalination of saline wastewater due to its excellent structure. However, additives are usually introduced during the synthesis of FeHCF in order to avoid [Fe(CN)6]3–vacancy defects filled by ligand water, which can result in the appearance of harmful byproducts and additional water treatment costs. In this study, an additive-free in situ vacancy repair strategy is proposed for the rapid synthesis of high-quality FeHCF in a saturated K3Fe(CN)6solution. During the process of synthesizing FeHCF in solution, a high concentration of [Fe(CN)6]3–is found to facilitate the binding of Fe3+to [Fe(CN)6]3–and hinder the hydrolysis and coordination reaction of Fe3+. After undergoing repair, FeHCF4 demonstrates an increased capacity and highly reversible electrochemical performance due to the robust structure. When utilized as Faraday cathodes in hybrid capacitive deionization (HCDI) systems, FeHCF4 exhibits a higher salt removal capacity (65.67 mg g–1) and lower energy consumption (0.68 kWh kg–1-NaCl) compared to unrepaired FeHCF1, while still maintaining excellent cycling performance. This environmentally friendly approach of repairing vacancies serves as a source of inspiration for the advancement of high-performance Prussian Blue analogues as capacitive sodium-removing materials.

Acute aortic syndrome is a life-threatening emergency condition. Previous systematic reviews of D-dimer diagnostic accuracy for acute aortic syndrome have been contradictory and based on limited data, but recently published studies offer potential for a more definitive overview. We aimed to perform a systematic review and meta-analysis to determine the diagnostic accuracy of D-dimer for diagnosing acute aortic syndrome.

Optimum grinding parameters are crucial for achieving high-quality grinding of helical tooth surfaces for worm drives. The complex coupling motion relationship and formation mechanism between the worm blank and the grinding head make it difficult to predict the effect of grinding parameters on tooth surface roughness. Therefore, we developed a prediction model for the worm tooth surface roughness under conjugate grinding and applied it to the Roller Enveloping Worm Reducer (REWR). The forming process of the theoretical worm tooth surface during the grinding process was modeled by using the conjugate meshing principle. Considering the plowing and cutting effects of grinding particles on the tooth surface at different design parameters, feed speeds, and rotational speeds of the grinding head, the roughness prediction equation was established based on the theory of the maximum depth of valley bottom. Through the coupling analysis of the theoretical tooth surface model and the roughness prediction model, the prediction of the worm tooth surface roughness is realized. Based on the validated model, the influences of grinding parameters on the worm tooth surface roughness of REWR were quantitatively discussed. This study is of great significance for optimizing process parameters in the grinding of complex spatial surface transmissions.

A five-element medium-entropy filler alloy with composition of Ti-(18 ~ 24)Mn-(12 ~ 18)Fe-(3 ~ 8)Ni-(3 ~ 8)Zr (wt.%) was proposed for vacuum brazing of TiAl-based alloy. The filler alloy was mainly composed of Ti-based solid solution and Ti-(Fe, Mn) compound dissolved with elements of Ni and Zr. The filler alloy ingot was ground into powder and then the filler powder was preset into the V-shaped groove butt joint with a gap of 50 μm. The Ti-Mn-Fe-Ni-Zr brazing alloy showed the liquidus temperature of 1060.1 °C, and also presented excellent wettability on TiAl substrate at 1110 °C for 10 min. The brazed joint mainly consisted of γ-TiAl, α2-Ti3Al, and residual brazing filler reaction phase. The brazing condition of 1210 °C/45 min exhibited the maximum joint thickness of 308 μm and the maximum area percentage of γ-TiAl phase of 33.77%, with almost elimination of residual brazing filler reaction phase within the joint, and meanwhile offered the maximum room-temperature tensile strength of 418 MPa, 70.85% of the base alloy. The joint fracture showed a mixed mode of intergranular and transgranular fracture.

Gliomas are aggressive CNS tumors where the epithelial–mesenchymal transition (EMT) is crucial for prognosis. We developed an EMT-based score predicting overall survival (OS) and conducted pathway analyses, revealing functions such as cell proliferation and immune response in glioma progression. The EMT score, correlated with immune functions and cell infiltration, shows potential as an immune response indicator. We identified two promising compounds, BIX02189 and QL-XI-92, as potential glioma treatments based on candidate gene analysis.

Single-beam/multibeam scanning is a key technology in modern wireless communications, where extensive works have been devoted to improving the performance of devices, such as the coverage capability. In this letter, a 2-bit single-polarization reconfigurable intelligent surface (RIS) for single-beam and multibeam radiation in the far field is proposed. Two diodes are loaded onto a trapezoidal patch, utilizing a four-layer printed circuit board (PCB) structure to construct independent control of 2-bit phase discretization, easy to manufacture. To enlarge the beam scanning range of the RIS, the cell period is designed as 0.41λ. Each p-i-n diode is independently controlled by the field-programmable gate array (FPGA), enabling real-time 2-D beam scanning. For demonstration, the prototype of the RIS is fabricated and measured, which is formed of 16 × 16 units and operates at 3.5 GHz. The far-field radiation patterns corresponding to single-beam and multibeam radiation are measured in the microwave chamber and the scanning beams with range of ±60° are also measured. In the direction of θ = 0°, ϕ = 0 °, the RIS has a gain as high as 21.3 dBi, the sidelobe level is less than −11 dB, and the cross polarization is lower than −30 dB.

Uncertainty exists about whether lowering systolic blood pressure to less than 120 mm Hg is superior to that of less than 140 mm Hg, particularly in patients with diabetes and patients with previous stroke.

Considering carbon emission in inventory management model is a hot topic in current academic circles. Studying inventory pricing can provide managers with better managerial insights. Economic order quantity model mainly solves the inventory management problem of demand determination. However, due to the complex market environment in real life, it is difficult to meet the conditions of constant demand. In addition, with the enhancement of low-carbon awareness of enterprises, the study of pricing model based on low-carbon policies has also attracted the attention of a large number of scholars. The robust optimization theory is applied, the inventory pricing model of demand fluctuation under carbon cap, carbon tax and carbon cap-and-trade policies is considered, the robust equivalence form of the problem is studied. The profit comparison under different policies is given. Numerical experiments show that the carbon cap-and-trade policy can better control the carbon emission of enterprises.

This study aims to develop a magnetorheological (MR) damper for semi-active knee prostheses to restore the walking ability of transfemoral amputees. The core dimensions of the MR damper were determined via theoretical magnetic field calculations, and the theoretical relationship between current and joint torque was derived through electromagnetic simulation. Then, a physical prototype of the semi-active prosthetic knee equipped with the MR damper was manufactured. Based on the data obtained from angle sensor, pressure sensor (loadcell), and inertial measurement unit (IMU) on the prosthesis, a matching control algorithm is developed. The joint torque of the MR damper can be adaptively adjusted according to the walking speed of the amputee, allowing the amputee to realize a natural gait. The effectiveness of the control program was verified by the ADAMS and MATLAB co-simulation. The results of the test and simulation show that the MR damper can provide sufficient torque needed for normal human activities.

To overcome the inaccuracy problem of the traditional wedge evaluation of steel plates and strips caused by the randomness of the thicknesses of two local points and improve the reliability of the wedge index, the double-centroid method for the wedge evaluation was proposed, and a model based on the centroid theory was established. Meanwhile, an integral model for the discrete thickness values of the cross-section profiles was derived. The discussion focused on the distinct characteristics of the two-point method, asymmetric method, and double-centroid method in evaluating the asymmetric distribution of cross-sections. The three methods were employed to evaluate the wedge values of both the theoretical and measured cross-sections of steel plates and strips, and the accuracies of three wedge evaluation models were analyzed and discussed. The results showed that the double-centroid method objectively reflects the degree and variation characteristics of the wedge values of the cross-sections of steel plates and strips, and this method is feasible, reliable, and outstanding.

Controlling the growth direction of one-dimensional (1D) nanostructures is crucial for their resulting applications. In this work, the growth of MoO2nanobelts was directed into three directions on a flat C-plane sapphire and one direction on an annealed M-plane sapphire, respectively. Structural characterizations show that these MoO2nanobelts have high crystal quality and grow epitaxially along a consistent [010] crystallographic orientation. UV–visible absorption spectra indicate that these self-oriented MoO2nanobelts have a large intrinsic band gap of 3.9 eV. Angle-resolved polarized Raman spectra confirm that these nanobelts exhibit remarkable anisotropic properties. In situconductivity measurements show that these MoO2nanobelts have a high conductivity of 1.6 × 103S/cm. Last, two self-assembly models are proposed for the horizontally oriented growth of these MoO2nanobelts. These horizontally oriented MoO2nanobelts are promising for potential applications in various new micro/nanophotonic and electronic devices.

Accurate in vivo imaging of G-quadruplexes (G4) is critical for understanding the emergence and progression of G4-associated diseases like cancer. However, existing in vivo G4 fluorescent probes primarily operate within the near-infrared region (NIR-I), which limits their application accuracy due to the short emission wavelength. The transition to second near-infrared (NIR-II) fluorescent imaging has been of significant interest, as it offers reduced autofluorescence and deeper tissue penetration, thereby facilitating more accurate in vivo imaging. Nonetheless, the advancement of NIR-II G4 probes has been impeded by the absence of effective probe design strategies. Herein, through a “step-by-step” rational design approach, we have successfully developed NIRG-2, the first small-molecule fluorescent probe with NIR-II emission tailored for in vivo G4 detection. Molecular docking calculations reveal that NIRG-2 forms stable hydrogen bonds and strong p–p interactions with G4 structures, which effectively inhibit twisted intramolecular charge transfer (TICT) and, thereby, selectively illuminate G4 structures. Due to its NIR-II emission (940 nm), large Stokes shift (90 nm), and high selectivity, NIRG-2 offers up to 47-fold fluorescence enhancement and a tissue imaging depth of 5 mm for in vivo G4 detection, significantly outperforming existing G4 probes. Utilizing NIRG-2, we have, for the first time, achieved high-contrast visualization of tumor metastasis through lymph nodes and precise tumor resection. Furthermore, NIRG-2 proves to be highly effective and reliable in evaluating surgical and drug treatment efficacy in cancer lymphatic metastasis models. We are optimistic that this study not only provides a crucial molecular tool for an in-depth understanding of G4-related diseases in vivo but also marks a promising strategy for the development of clinical NIR-II G4-activated probes.

This paper proposes two algorithms for dual sourcing inventory systems with Tailored Base-Surge policies. The first algorithm solves a system of linear equations to calculate inventory positions, performance measures and their derivatives, and the second algorithm then uses them in the gradient-based type of method to find the optimal Tailored Base-Surge policy. Numerical experiments show that the two algorithms work well.

This paper aims to tackle the issues of evaluating the dynamic performance of fiscal poverty alleviation in 22 Chinese provinces (regions) over 2016–2019. First, we open up the internal structure of the fiscal poverty alleviation system (FPAS) and clarify its input-output process as a two-stage series system consisting of the public investment process and poverty reduction process. On this basis, we construct dynamic network DEA models with and without carryover activities for measuring the period efficiency and overall efficiency of FPASs (i.e., FPAS efficiency) and the period efficiency and overall efficiency of evaluation indicators (i.e., indicator efficiency), and also prove the relationship between the two proposed models. Second, we combine the proposed dynamic network DEA models and Bootstrap resampling method to assess the robustness of FPAS efficiency for exploring the risk of returning to poverty for each FPAS. The results show that: (i) the carryover activities have some impact on the FPAS efficiency and indicator efficiency; (ii) the period efficiency shows an upward trend, and most of FPASs or evaluation indicators have been at high efficiency in the sample period, but there is still regional heterogeneity; (iii) there are some differences between the indicator efficiency and there are some inconsistencies between them and the FPAS efficiency; (iv) bootstrap resampling results indicate that several FPASs have a great risk of returning to poverty.

Robotic belt grinding serves as a pivotal method for achieving precision machining in re-manufacturing of aeroengine components made of Inconel 718. During grinding, the heat partition ratio (Rw) significantly influences the quality of the machined workpiece, which is affected by many grinding parameters. Belt wear, which is an unavoidable phenomenon during grinding, can substantially impact Rw. However, previous research works have paid little attention to the effect of belt wear. In this study, the variation of Rwwith belt wear is comprehensively investigated by observing heat generation and heat input. Firstly, the belt wear behaviors are qualitatively and quantitatively described. Then, the impact mechanism of belt wear on force-related characteristics is analyzed to clarify the change rule of heat generation. Following this, the variations of temperature-related characteristics during belt wear are examined. Meanwhile, the heat input is obtained by the combination of finite element analysis and the inverse heat method. Finally, a rapid growth followed by a gradual decrease pattern of Rwwith belt wear is derived and analyzed. The findings in this paper lay a crucial foundation for controlling the grinding quality during robotic belt grinding Inconel 718.

A Cu(I)-catalyzed highly regioselective synthesis of 2-acetamidequinoline N-oxides using dioxazolones with quinoline N-oxides has been reported. The reaction possesses mild reaction conditions and excellent functional group compatibility. Furthermore, the addition of hydrochloric acid promotes the decomposition of copper complexes, which is beneficial for postprocessing.

Idiopathic pulmonary fibrosis (IPF) is a progressive and lethal lung disease with an elusive etiology. Aberrant activation of c-Jun N-terminal kinase 1 (JNK1) has been implicated in its pathogenesis. Through a combination of structure-based drug design and structure–activity relationship (SAR) optimization, a series of pyrimidine-2,4-diamine scaffold derivatives have been developed as potent JNK1 inhibitors. Compound E1was identified with low nanomolar JNK1 inhibitory potency (IC50= 2.7 nM). The introduction of a dimethylamine side chain has significantly enhanced the ability of E1to inhibit c-Jun phosphorylation, surpassing the clinical candidate CC-90001. Molecular dynamics simulations revealed a binding free energy of −50.46 kcal/mol for E1. Moreover, E1displayed satisfactory pharmacokinetic properties, with a bioavailability of 69% in rats. Furthermore, compound E1exerted significant antifibrotic effects in a bleomycin-induced IPF mouse model and prevented a TGF-β-induced epithelial-to-mesenchymal transition in vitro. These findings position E1as a promising lead for further drug development targeting IPF.

• (ZrO 2 -SiO 2) f /ZrB 2 -SiOC composites with a continuous multilayer structure have been prepared. • The continous multilayer structure design allows impedance matching and multiple electromagnetic wave attenuation within multi-period layers. • The composites have excellent electromagnetic wave absorption performance, radar cross-section reduction and thermal insulation in dynamic heating environment. • The composites exhibit an effective absorbing bandwidth of 4.2 GHz, covering the entire X-band. To simultaneously improve the microwave absorption and thermal insulation properties of the ceramic materials for stealth high-speed vehicles, layered composites made of polymer-derived SiOC/ZrB 2 reinforced by ZrO 2 /SiO 2 fibers were reported in this work. The composites possess a continuous multilayer structure, which was fabricated via the precursor impregnation assisted by hot press curing and pyrolysis using the transparent ZrO 2 /SiO 2 fibers and polymer-derived SiOC and nano ZrB 2. The layered composites show an effective absorption band (EAB) of 4.2 GHz at a thickness of 2.9 mm and a minimum reflection loss of –59.34 dB. The exceptional electromagnetic (EM) wave attenuation capability is ascribed to the impedance matching as well as massive EM wave loss caused by the multilayers in which the nano ZrB 2 provides interfacial polarization and electrical conduction loss. With a design of the multi-curvature arch structure, a remarkable reduction of radar cross section can be achieved. Besides, the layered composites exhibit good oxidation resistance and thermal insulation when exposed to the dynamic heating environment, demonstrating the potential application in harsh environments used for multifunctional electromagnetic absorbing materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Defect engineering is an extremely effective strategy for modifying metal–organic frameworks (MOFs), which can break through the application limitations of traditional MOFs and enhance their functionality. Herein, we report a highly robust nanoporous thulium(III)–organic framework, {[Tm2(BDCP)(H2O)5](NO3)·3DMF·2H2O}n(NUC-105), with [Tm(COO)2(H2O)]nchains and [Tm2(COO)4(H2O)8] dinuclears as metal nodes and 2,6-bis(2,4-dicarboxylphenyl)-4-(4-carboxylphenyl)pyridine (BDCP) linkers. In NUC-105, each of the four chains of [Tm(COO)2]nand the two rows of [Tm2(COO)4(H2O)8] units is unified by the organic skeleton, resulting in a rectangular nanochannel with dimensions of 15.35 Å × 11.29 Å, which leads to a void volume of 50%. It is worth mentioning that the [Tm2(COO)4(H2O)8] cluster is very rare in terms of its higher level of associated water molecules, implying that the activated host framework can serve as a strong Lewis acid. NUC-105aexhibited great heterogeneous catalytic performance for CO2cycloaddition with epoxides under the reaction conditions (0.60 mol % NUC-105a, 5.0 mol % n-Bu4NBr, 65 °C, 5 h), ensuring exclusive selectivity and high conversion rates. In addition, NUC-105a’s strong catalytic impact on the Knoevenagel condensation of aldehydes and malononitrile can be attributed to the collaboration between the drastically unsaturated Lewis acidic Tm3+centers and Lewis basic pyridine groups.

In this paper, to tackle the blockage issue in massive multiple-input-multiple-output (mMIMO) systems, a reconfigurable intelligent surface (RIS) is seamlessly deployed to support devices with ultra-reliable and low-latency communications (URLLC). The transmission power of the base station and the phase shifts of the RIS are jointly devised to maximize the weighted sum rate while considering the spatially correlation and channel estimation errors. Firstly, the relationship between the channel estimation error and spatially correlated RIS’s elements is revealed by using the linear minimum mean square error. Secondly, based on the maximum-ratio transmission precoding, a tight lower bound of the rate under short packet transmission is derived. Finally, the NP-hard problem is decomposed into two optimization problems, where the transmission power is obtained by geometric programming and phase shifts are designed by using gradient ascent method. Besides, we have rigorously proved that the proposed algorithm can rapidly converge to a sub-optimal solution with low complexity. Simulation results confirm the tightness between the analytic results and Monte Carlo simulations. Furthermore, the two-timescale scheme provides a practical solution for the short packet transmission.

Joint detection and communication (JDC) systems can implement both functionalities simultaneously using the same hardware and software resources. This feature proves advantageous in reducing the size and power consumption of underwater vehicles. This paper develops a JDC system based on multi-input multi-output sonar by using orthogonal linear frequency modulation (OLFM) waveforms. Here, the proposed OLFM-based JDC system (OLFM-JDC) considers the detection functionality as the primary task. Therefore, OLFM-JDC exploits the mainlobe of transmit beam to detect targets and the sidelobes to communicate with the remote receivers. To enhance the information embedding capacity, the waveform diversity and the combination of index and phase modulations are utilized. Particularly, we propose a low-complexity two-step decoder to simplify the information decoding. Furthermore, the two-step decoder effectively utilizes multipath information to improve the performance of index decoding, and it can even outperform the maximum likelihood scheme when assessed within a simulated South China Sea acoustic channel. The numerical results demonstrate that OLFM-JDC achieves higher data rates and lower error rates compared to the JDC systems that only utilize phase modulation. Additionally, the simultaneous transmission of multiple waveforms facilitates target detection by utilizing the generalized high-resolution range profile synthesis technique. Performance analysis indicates that OLFM-JDC exhibits similar resolution performance to systems implementing a wideband waveform.

In the simultaneous localization and mapping (SLAM) technique, the presence of cumulative errors in laser odometry positions leads to localization bias or even map-building failure. To address this problem, a laser SLAM method called PA-SLAM based on ground plane constraints and two-step accurate identification of loopback frames is proposed. In the point cloud preprocessing process, the Patchwork++ method is introduced to obtain the ground plane constraints to reduce the localization error caused by invalid feature point matching. Then, accurate six-degree-of-freedom bit positions of the carrier are obtained from Lidar orientation and map construction (LOAM), candidate loopback frames are obtained by searching within a certain radius according to the k-dimensional (K-D) tree data structure, and a Lidar Iris descriptor is introduced to calculate the similarity scores among the candidate frames. Finally, the fast generalized iterative closest point (FasterGICP) algorithm is introduced to obtain the loopback position constraints to correct the global pose, so as to obtain more accurate localization information. The proposed method is compared with the LeGO-LOAM and SC-LeGO-LOAM algorithms on the KITTI dataset. The experimental results show that the absolute position root-mean-square error (RMSE) of this method is reduced by 45.7$\%$ and 48.3$\%$ on average relative to the above two algorithms, which plays a significant role in eliminating the cumulative error of the position, and realizes a more robust and accurate localization and 3-D map construction.

Cooperative guidance problems with impact time consensus and time-varying line-of-sight (LOS) formation for the fixed-wing unmanned aerial vehicle (UAV) swarm under actuator faults are studied. First, an axial and normal controllable guidance model is established along with an expression of the actuator fault model. Second, an observer-based fixed-time cooperative guidance law is proposed to achieve impact time consensus and LOS formation within a predetermined time. Third, the adaptive gains are proposed to deal with the coupling effect of the target maneuver and unknown actuator faults. In addition, the convergence of the proposed cooperative guidance law is analyzed using Lyapunov theories. Finally, a multiple fixed-wing UAV guidance experimental platform consisting of three fixed-wing UAVs is constructed. The adaptive fixed-time fault-tolerant cooperative guidance law is applied on the experimental platform and well verified in the practical application.

As high-voltage and high-power electronic devices, such as insulated gate bipolar transistors (IGBTs) develop toward higher levels, the generated heat and operating temperature rise rapidly, causing the problem of insulation packaging failure to become more serious. In this article, to study the gas production mechanism of the high-temperature thermal cracking reaction of silicone gel material, the thermogravimetric–infrared spectroscopy (TG–IR), thermogravimetric–mass spectrometry (TG–MS), pyrolysis–gas chromatography–mass spectrometry (Py–GC–MS), and molecular dynamics simulation are used to test and simulate the changes of functional groups, thermal cleavage products, and minor molecule gases during the high-temperature thermal cleavage of silicone gel with temperature in an argon atmosphere. Research indicates that under the action of high temperature, the thermal cracking reaction of silicone gel begins at about 330 °C, and the degree of reaction reaches its maximum at about 561 °C. The main products of high-temperature thermal cracking of silicone gel contain two parts. First, H2, CH4, C2H6, C2H4, CO2, $\text{H}_{{2}}\text{O}$ , H4Si, CH $_{{2}}\text{O}$ , and other small molecular gases. From the microscopic level analysis, CH $_{{2}}\text{O}$ is the first to be produced in the thermal cracking process of silicone gel than other oxygen-containing gases, and the source of oxygen comes from independent chain breakage. Therefore, the generation of CH $_{{2}}\text{O}$ means that the structural quality of the silicone gel has changed, which will lead to the failure of the insulation package. If $\text{H}_{{2}}\text{O}$ , CO2, and other oxygen-containing gases are generated, it means that the failure of the insulation package will be aggravated. Second, the macromolecular products are mainly cyclosiloxanes, esters, aldehydes, alcohols, acids, and other functional organics. The generation of minor molecular gases during thermal decomposition primarily originates from reactions within the side chain groups. Therefore, changes in the side chain structure can enhance the thermal resistance of silicone gel. The conclusions drawn in this article can offer a specific theoretical basis for monitoring insulation fault gases in silicone gel to encapsulate high-voltage and high-power semiconductor devices.

Privacy-preserving federated learning, as one of the privacy-preserving computation techniques, is a promising distributed and privacy-preserving machine learning (ML) approach for Internet of Medical Things (IoMT), due to its ability to train a regression model without collecting raw data of data owners (DOs). However, traditional interactive federated regression training (IFRT) schemes rely on multiple rounds of communication to train a global model and are still under various privacy and security threats. To overcome these problems, several noninteractive federated regression training (NFRT) schemes have been proposed and applied in a variety of scenarios. However, there are still several challenges: 1) how to protect the privacy of DOs’ local dataset; 2) how to realize highly scalable regression training without linear dependence on sample dimension; 3) how to tolerate DOs’ dropout; and 4) how to enable DOs to verify the correctness of aggregated results returned from the cloud service provider (CSP). In this article, we propose two practical noninteractive federated learning schemes with privacy-preserving for IoMT, named homomorphic encryption based NFRT (HE-NFRT) and double-masking protocol based NFRT (Mask-NFRT), respectively, which are based on a comprehensive consideration of NFRT, privacy concerns, high-efficiency, robustness, and verification mechanism. The security analyses display that our proposed schemes are able to protect the privacy of DOs’ local training data, resist collusion attack, and support strong verification to each DO. The performance evaluation results demonstrate that our proposed HE-NFRT scheme is desirable for a high-dimensional and high-security IoMT application while Mask-NFRT scheme is desirable for a high-dimensional and large-scale IoMT application.

With the continuous development of educational informatization, more and more emerging technologies are applied in teaching activities. These technologies provide massive and multidimensional information for teaching research, but at the same time, the information obtained by teachers and students presents an explosive increase. Extracting the core content of the class record text through text summarization technology to generate concise class minutes can significantly improve the efficiency of teachers and students to obtain information. This article proposes a hybrid-view class minutes automatic generation model (HVCMM). The HVCMM model uses a multilevel encoding strategy to encode the long text of the input class records to avoid memory overflow in the calculation after the long text is input into the single-level encoder. The HVCMM model uses the method of coreference resolution and adds role vectors to solve the problem that the excessive number of participants in the class may lead to confusion about the referential logic. Machine learning algorithms are used to analyze the topic and Section of the sentence to capture structural information. We test the HVCMM model on the Chinese class minutes dataset (CCM) and the augmented multiparty interaction (AMI) dataset, and the results show that the HVCMM model outperforms other baseline models on the ROUGE metric. With the help of the HVCMM model, teachers can improve the efficiency of reflection after class and improve the teaching level. Students can review the key content to strengthen their understanding of what they have learned with the help of the class minutes automatically generated by the model.

In this letter, we investigate the hybrid precoding design problem for the near-field wideband terahertz (THz) systems. Due to the large physical size of the whole array, the extremely large-scale antenna array (ELAA) exhibits spatial non-stationarity across the array. Users only effectively communicate with a portion of the antenna elements of ELAA called visibility regions (VRs). To leverage this characteristic for reducing the computational complexity in hybrid precoding design, we initially develop a VR detection algorithm to identify the corresponding VRs for different users. Subsequently, we employ the acquired VR information for true-time delayer (TTD)-based hybrid precoding design to mitigate the beam split effect. Simulation results validate that the proposed algorithm significantly reduces the computational complexity compared to other benchmark schemes while maintaining negligible performance loss.

X-ray detection is a promising visualization method for internal defects’ diagnosis within the power equipment, while its impact on partial discharge (PD) should be clarified due to the strong ionizing ability. In this work, the discharge dynamics under different X-ray irradiation doses in gas insulated switchgear (GIS) are numerically investigated by coupling the Monte Carlo N-Particle (MCNP) and 2-D particle-in-cell/Monte Carlo collision (PIC/MCC) model, taking into account the conversion from irradiation dose to preionization in space. It is observed that the increment in irradiation dose results in a faster propagating discharge with a significantly expanded volume, weakening the insulating performance of the gap against overvoltage. This is correlated with the insignificant difference in electron energy both in the channel and at the discharge front, which accelerates the synchronized development of electron avalanches and thus promotes diffuse discharge formation. The discrete seed electrons caused by X-ray irradiation can guide the discharge propagating path with a larger dose. The results in this work demonstrate the essential relationship between X-ray irradiation and discharge dynamics, providing a reference for X-ray detection applied in electrical equipment.

In high-voltage cables, the buffer layer (BFL), commonly composed of polyethylene terephthalate (PET) and sodium polyacrylate (NaPA) covered by carbon black, can undergo severe deterioration of electrical conductivity under electrohumid stress, which can easily induce serious ablation faults. However, the deterioration process of BFL conductivity is still lack of comprehension, hindering the condition assessment of cables and boosting the risk of faults. This article investigates the deterioration of BFL conductivity under electrohumid stress. Accelerated deteriorating experiments are carried out on dry and humid BFL specimens for 6 h under the ac voltage of 30 V. The current density of BFL first upsurges and then decreases exponentially with time under the electrohumid stress. Simultaneously, gas products of hydrocarbons, carbon oxide, and hydrogen (H2) are generated, the concentrations of which follow exponential evolution trends as well. Under electrohumid stress, the alkoxy groups in PET fibers of BFL are heavily damaged, and phenolic hydroxyl groups are generated as verified by X-ray photoelectron spectroscopy. Furthermore, electrochemical reactions occur in the BFL-Al system under electrohumid stress as verified by Tafel curves. It is proposed that the conductivity deterioration of BFL originates from the damage to conductive networks, which is mainly induced by the thermal decomposition of PET fibers in BFL through the current heating effect and the electrical barrier by high-resistive solids from electrochemical reactions.

This article mainly explores the fixed-time control problem of fuzzy semi-Markov systems with uncertainties and unknown transition rates. Firstly, the T-S fuzzy semi-Markov system is established by using the membership relation of fuzzy logic and Markov probability property. Then, unlike the existing fixed-time control strategies, this work uses a hyperbolic sine function to replace the traditional multiple powers fixed-time control method and construct a novel fixed-time adaptive integral sliding mode control strategy, which reduces the complexity of the controller and adaptive law while optimizing the sliding mode surface and improving the fixed-time convergence performance of the system. Moreover, compared with current methods that require the assumption that the unknown function satisfies the Lipschitz condition or is bounded, the fully connected neural network is introduced to approximate the unknown nonlinear function in the system, improving the intelligence and practicality of the controller. Finally, the theoretical results are verified through numerical simulation, showing the superior performance of achieving fixed-time stability through the proposed control scheme, the gap in the study of fixed-time control using hyperbolic sine functions and fully connected neural networks is filled.

Multiagent reinforcement learning (MARL) promises outstanding performance for multiintersection traffic signal control systems (TSCS), enabling intelligent administration of cities. However, the vulnerability of MARL algorithms to adversarial attacks has raised concerns about the security of TSCS. In this article, we explore the robustness of MARL-based TSCS against adversarial attacks, propose a black-box multiobject attack strategy, and assign an attack budget to ensure stealthiness. We design a dynamic threshold-based selection of critical states to minimize the cumulative reward with a limited number of attacks. In addition, we present a lightweight agnostic dynamic threshold-based defense mechanism by enhancing the worst-case performance of the policy. We formulate it as a min-max optimization problem, i.e., minimizing the quantity of training sample alterations while maximizing the cumulative discount reward of policy against the perturbed states. Extensive experiments on simulation of urban mobility (SUMO) demonstrate that the proposed attack policy can significantly reduce the performance of TSCS.

The complexity of the structure and operating process of the large-scale petrochemical equipment makes it difficult to realize effective health management. In this article, a natural gas dehydration process digital twin (DT) is proposed for condition evaluation. The framework and detailed DT models are introduced. The geometric, process, behavioral, and rule models in DT map physical entities geometric information, working process, control process, and hidden condition evolution process, respectively. A triethylene glycol dehydration DT application system is developed and the overall reality-virtual mapping process of DT for equipment condition evaluation is demonstrated. The ability of the DT to represent the petrochemical processes is verified with real monitoring data. The condition evaluation ability of the DT application system is validated by failure event and typical process parameters. The methodology proposed in this article can be applied to petrochemical fields to improve the safety of the operational process.

This letter presents an active frequency-selective rasorber (AFSR) with switchable dual operating modes at L-band. The proposed frequency-selective rasorber (FSR) comprises of a resistive layer and a frequency-selective surface layer loaded with PIN diodes, separated by an air spacer. The operating mechanism is elaborated by analyzing the equivalent circuit model. By controlling the states of the PIN diodes, the AFSR can be switched from the absorption–transmission–absorption (A-T-A) to absorption–reflection–absorption (A-R-A) modes. In the A-T-A mode, the transmission peak is 0.21 dB at 1.89 GHz, while the absorption band is 0.87 GHz to 3.42 GHz. In the A-R-A mode, the reflection peak is 0.15 dB at 1.91 GHz, while the absorption bands are (0.95 to 1.34) GHz to (2.1 to 3.51) GHz. A prototype of the proposed FSR was fabricated and measured to verify the design concept.

In this letter, a leaky-wave antenna (LWA) based on corrugated offset parallel striplines (COPS), featuring completely backfire-to-endfire scanning capacity, is investigated. The LWA is composed of the COPS consisting of two rows of “U-shaped” units and periodically loaded open-ended stubs at the outer side. The stubs create a longitudinal current distribution, realizing omnidirectional radiation components of element factor in the scanning plane. The COPS provides the larger value and more rapid growth rate of phase shift in the fast-wave region of n = −1 space harmonic (SH) compared with stripline, achieving pure n = −1 SH radiation and improving scanning rate. Moreover, the open stopband at the broadside is suppressed by loading extra relatively shorter stubs at the location of a quarter of the period length from the existing stubs. To verify the performance of the LWA, a prototype is simulated, fabricated and measured, showing a continuous beam scanning from the backfire to endifre direction in the frequency band from 7.85 GHz to 11.15 GHz. The measured results indicate that the LWA achieves a peak gain of 12.4 dBi and a peak efficiency of 73% in the working band.

A novel mixed-potential integral equation (MPIE)-based sub-structure generalized eigenvalue equation (SSGEE) for multilayer structure is proposed in this letter. Compared to state-of-the-art sub-structure characteristic mode (CM) formulations based on electromagnetic field integral formulation, the proposed MPIE-based SSGEE significantly reduces computation time and computer memory required. In addition, the proposed MPIE-based SSGEE can also be applied on different parts of a single object, which is well suited for obtaining the radiation characteristic of every radiator in the multiradiator system.

In this letter, a broadband compact dual-polarized solar cell phased array antenna is proposed. The proposed dual-polarized dipoles are arranged in a “T” shape, which not only makes the antenna compact and easy to fabricate, but also expands the working bandwidth by utilizing the coupling between the tightly arranged dipoles. Moreover, metal split-rings are introduced to further improve the impedance match and finally achieve a broad bandwidth of 1.1 GHz to –2.5 GHz and a large-angle two-dimensional phase scanning ability of ±45° under a low profile of 0.08λ0 (λ0 is the free-space wavelength at the center frequency). The measured maximum realized gain is 10.86 dBi for a horizontally polarized antenna, and the measured radiation efficiency is 61%–88.3% in the working frequency band. Moreover, the solar cells can achieve 100% insolation with an expected solar cell coverage ratio of 77.8%. This compact dual-polarized solar cell phased array antenna is scalable and exhibits promising usage in green wireless communication systems.

Fiber optic surface plasmon resonance (SPR) sensors have achieved a large number of solutions for sensing physical quantities such as refractive index, micro displacement, curvature, strain, etc. However, there are few schemes for sensing torsional physical quantities. This article proposes an optical fiber SPR torsion sensor based on a threaded structure. A threaded structure that is prone to deformation during torsion is etched on the optical fiber. After the threaded area, an SPR sensing area is created. Clockwise rotation causes compression deformation in the threaded area, while counterclockwise rotation causes tensile deformation in the threaded area, resulting in a change in the optical transmission mode of the threaded area, changing the SPR incidence angle, causing the corresponding SPR resonance valley to move. Torsion sensing is achieved through the shift of the SPR resonance wavelength, and the torsion direction is determined by the shift direction of wavelength. The experiment indicates that the sensing probe has a clockwise twist sensitivity of 0.9088 nm/(rad/m) and a counterclockwise twist sensitivity of −0.8291 nm/(rad/m) within the detection range of −47.10 rad/nm to 47.10 rad/nm, providing a new scheme for directional detection of torsional physical quantities.

Delta-sigma modulation (DSM) has been considered as an effective means to replace the common public radio interface (CPRI) for the implementation of novel mobile fronthaul (MFH) architectures. However, the recent studies paid great attention on the performance optimizations of the delta-sigma modulators, which could help to enhance signal-to-noise ratio (SNR). Few of them focus on the improvement of noise immunity. In this paper, we apply three-dimensional (3D) constellations to DSM, thereby improving the noise immunity performance of the ultra-high order quadrature amplitude modulation (QAM) constellations. Moreover, addressing the huge number of constellation points in the ultra-high order constellations, we propose a novel constellation approach based on 3D-constellation partition. This approach significantly simplifies the transmission system, leading to an 8-fold improvement in processing efficiency. The experimental demonstrations were realized in a 100 GHz photonics-assisted W-band transmission system, indicating that the transmission scheme based on 3D-constellation could obtain an approximate 0.5 dB gain in receiver sensitivity compared to that using 2D-constellation. Verified by the transmission of ultra-high order DSM signals in the 15-km single-mode fiber (SMF) and 2.6-m W-band wireless link, we could achieve 262144-QAM at a rate of 17.5 Gb/s under a simple digital signal processing (DSP).

This article is concerned with resilient formation tracking problems for general linear multiagent systems, where the leader’s control input is unavailable to all the followers and partial followers’ behaviors are malicious due to the node attacks. Despite the presence of the nonautonomous leader and the adversarial followers, the remaining benign followers are still expected to track the leader’s trajectory with the prescribed time-varying formation. To this end, a resilient scheme comprising an attack detection and isolation strategy and a formation tracking protocol is proposed. The detection strategy enables every benign follower to identify its adversarial neighbors with two-hop communication information, as long as the underlying topology meets given conditions. Then, the detected adversarial agents are directly removed to avoid the spread of their influence, which induces a new problem called node loss. To accommodate possible node loss events, the designed tracking protocol is independent of certain global knowledge, and its convergence is demonstrated by means of the impulsive Lyapunov functions. Finally, the proposed resilient scheme is verified by two simulation examples.

To enable distributed multiple mobile manipulator systems to complete collaborative tasks safely and stably, this article investigates and presents a motion generation scheme that considers both orientation and position coordination based on a distributed recurrent neural network. Moreover, physical limits are also considered. Specifically, the orientation and position coordination constraints and physical limits are modeled separately as equality and inequality constraints with coupled variables. Subsequently, a motion generation scheme for multiple mobile manipulators based on quadratic programming is established. Finally, a distributed linear variational inequality-based primal-dual neural network is constructed to solve the motion generation scheme and obtain the motion trajectories of all the mobile manipulators. The simulation results demonstrate that the hybrid orientation and position collaboration motion generation scheme effectively addresses the position and orientation coordination problem for multiple mobile manipulator systems. Compared to other schemes, the proposed scheme based on a distributed computing structure greatly enhances the stability of the system. Additionally, the proposed approach introduces orientation coordination and physical limits, which increases the practicality of the system.

Hydrogen sulfide (H2S), the third gasotransmitter discovered, regulates a variety of physiological functions. Whether H2S alleviates skeletal muscle ageing by regulating autophagy has not been reported. Mice were administered 150 mg/kg/day of D‐galactose (D‐gal), and C2C12 myotubes were cultured in 20 g/L D‐gal to induce ageing. Sodium hydrosulfide (NaHS) was employed as an exogenous donor in the treatment group. The intracellular concentration of H2S was quantified by the 7‐azido‐4‐methylcoumarin fluorescence probe. The proteins involved in the ubiquitin‐mediated degradation of AMPKα1 were detected by liquid chromatography tandem mass spectrometry (LC–MS/MS) and co‐immunoprecipitation (Co‐IP). S‐sulfhydration of USP5 was tested by a biotin‐switch assay. Associated proteins were analysed by western blot. NaHS was found to effectively restore the H2S content in both ageing gastrocnemius (+91.89%, P< 0.001) and C2C12 myotubes (+27.55%, P< 0.001). In comparison to the D‐gal group, NaHS was observed to increase the mean cross‐sectional area of muscle fibres (+44.91%, P< 0.001), to decrease the collagen volume fraction of gastrocnemius (−81.32%, P= 0.001) and to reduce the β‐galactosidase‐positive area of C2C12 myotubes (−28.74%, P< 0.001). NaHS was also found to reverse the expression of muscle atrophy F box protein (MAFbx), muscle‐specific RING finger protein 1 (MuRF1), Cyclin D1 and p21 in the ageing gastrocnemius tissue (MAFbx: −31.73%, P= 0.008; MuRF1: −32.37%, P= 0.003; Cyclin D1: +45.34%, P= 0.010; p21: −25.53%, P= 0.022) and C2C12 myotubes (MAFbx: −16.38%, P< 0.001; MuRF1: −16.45%, P= 0.003; Cyclin D1: +40.23%, P< 0.001; p21: −35.85%, P= 0.026). The AMPKα1–ULK1 pathway was activated and autophagy was up‐regulated in NaHS‐treated gastrocnemius tissue (p‐AMPKα1: +61.61%, P= 0.018; AMPKα1: +30.64%, P= 0.010; p‐ULK1/ULK1: +85.87%, P= 0.005; p62: −29.07%, P< 0.001; Beclin1: +24.75%, P= 0.007; light chain 3 II/I [LC3 II/I]: +55.78%, P= 0.004) and C2C12 myotubes (p‐AMPKα1: +77.49%, P= 0.018; AMPKα1: +26.18%, P= 0.022; p‐ULK1/ULK1: +38.34%, P= 0.012; p62: −9.02%, P= 0.014; Beclin1: +13.36%, P< 0.001; LC3 II/I: +79.38%, P= 0.017; autophagy flux: +24.88%, P= 0.034) compared with the D‐gal group. The effects of NaHS on autophagy were comparable to those of acadesine and LYN‐1604, and chloroquine could reverse its effects on ageing. LC–MS/MS and Co‐IP experiments demonstrated that USP5 is a deubiquitinating enzyme of AMPKα1. Following the knockdown of USP5, the activation of AMPKα1 was decreased (p‐AMPKα1: −42.10%, P< 0.001; AMPKα1: −43.93%, P< 0.001), autophagy was inhibited (p‐ULK1/ULK1: −27.51, P= 0.001; p62: +36.00, P< 0.001; Beclin1: −22.15%, P< 0.001) and NaHS lost its ability to up‐regulate autophagy. NaHS was observed to restore the expression (gastrocnemius: +62.17%, P< 0.001; C2C12 myotubes: +37.51%, P= 0.003) and S‐sulfhydration (+53.07%, P= 0.009) of USP5 and reduce the ubiquitination of AMPKα1. H2S promotes the deubiquitination of AMPKα1 by increasing the expression and S‐sulfhydration of USP5, thereby up‐regulating autophagy and alleviating skeletal muscle ageing.

This study aimed to investigate whether changes in presepsin, procalcitonin, high-sensitivity C-reactive protein, and interleukin 6 levels predict mortality in septic patients in the intensive care unit. This study enrolled septic patients between November 2020 and December 2021. Levels of presepsin, procalcitonin, high-sensitivity C-reactive protein, and interleukin 6 were measured on the first (PSEP_0, PCT_0, hsCRP_0, IL-6_0) and third days (PSEP_3, PCT_3, hsCRP_3, IL-6_3). Follow-up was performed on days 3, 7, 14, 21, and 28 after enrollment. The outcome was all-cause death. The study included 119 participants, and the mortality was 18.5%. In univariable Cox proportional hazards regression analysis, ΔPSEP (= PSEP_3 – PSEP_0) > 211.49 pg/mL (hazard ratio, 2.70; 95% confidence interval, 1.17–6.22), ΔPCT (= PCT_3 – PCT_0) > –0.13 ng/mL (hazard ratio, 7.31; 95% confidence interval, 2.68–19.80), ΔhsCRP (= hsCRP_3 – hsCRP_0) > −19.29 mg/L (hazard ratio, 6.89; 95% confidence interval, 1.61–29.40), and ΔIL-6 (= IL-6_3 – IL-6_0) > 1.00 pg/mL (hazard ratio, 3.13; 95% confidence interval, 1.35–7.24) indicated an increased risk of mortality. The composite concordance index for alterations in all 4 distinct biomarkers was highest (concordance index, 0.83; 95% confidence interval, 0.76–0.91), suggesting the optimal performance of this panel in mortality prediction. In decision curve analysis, compared with the Acute Physiology and Chronic Health Evaluation II and Sequential (sepsis-related) Organ Failure Assessment scores, the combination of the 4 biomarkers had a larger net benefit. Interestingly, interleukin 6 was predominantly produced by monocytes upon lipopolysaccharide stimulation in peripheral blood mononuclear cells. ΔPSEP, ΔPCT, ΔhsCRP, and ΔIL-6 are reliable biomarkers for predicting mortality in septic patients in the intensive care unit, and their combination has the best performance.Changes in PSEP, PCT, hsCRP, and IL-6 levels in septic patients on the third and first days of intensive care unit admission are reliable biomarkers for predicting mortality, and their combination has the best performance.

The cubic BN (c-BN)/diamond heterostructure proposed recently to possess 2-D electron gas (2DEG) could be a solution to diamond n-type field-effect transistors (FETs). However, the growth of c-BN/diamond system is still challenging. This work theoretically investigates the electronic transport property of c-BN/diamond heterostructure and explores its potential in electronic devices fields. The 2DEG sheet density in the heterointerface is calculated considering the effects of Schottky barrier height and modulation doping (MD) in c-BN barrier layer. The 2DEG mobility is the sum of five possible scattering mechanisms. The results show that the 2DEG mobility of c-BN/diamond heterostructure could be higher than 3000 cm2/ $\text {V}\cdot \text { s}$ at room temperature for 2DEG sheet density of $\sim 10^{{12}}$ cm−2 with a Schottky barrier of 1.1 eV and the undoped c-BN barrier thickness of 20 nm. Acoustic phonon (AC) scattering is the main scattering mechanism of the 2DEG for relatively large range of the c-BN layer thickness at room temperature. Remote surface roughness (RSR) scattering could dominate with very thin c-BN layer (<6 nm) if dense 2DEG was available even without MD, or otherwise, the MD scattering could dominate for thin c-BN layer if 2DEG mainly originated from the doping ionization. The temperature-dependent 2DEG mobility is determined by the phonon scatterings for temperature higher than ~100 K.

In this article, the origin of severe drain–source current kink effect in $\beta $ -Ga2O3 MOSFETs has been exploited by means of temperature- and pulse-dependent current–voltage (I–V) analysis. By reducing the pulse biasing widths, whereby the self-heating effect was negligible, the output characteristics were free of kink but with a rather low drain–source current density ( ${I}_{\text {DS}}$ ) at a high drain voltage ( ${V}_{\text {DS}}$ ) of 30 V. The current kink effect started to occur with a direct-current power consumption of approximately 850 mW/mm. The elimination of kink features was also observed together with a large ${I}_{\text {DS}}$ at elevated temperatures over 100 °C. These observations indicate that the kink effect is strongly related to thermal activation of incomplete ionized donors by either the self-heating effect or external intentional heating stress rather than high electric field. In terms of temperature-dependent current output characteristics, the thermal activation energy is determined to be 136 meV, which is consistent with the reported unintentional donors with a high activation energy of 110 meV. It implies that additional electrons are thermally activated and emitted from the incomplete ionized donors in $\beta $ -Ga2O3 channel or buffer layers through the self-heating effect, contributing to the channel conductivity modulation and the consequent current kink effect. These findings may bridge the knowledge gap between charge transport mechanisms and the reliability degradation of $\beta $ -Ga2O3 power switches.

The poor interface of silicon carbide (SiC)/SiO2 combined with the short channel effects (SCEs) and source contact resistance, collectively impacts the effective threshold voltage in SiC MOSFETs. In this work, a physical discrete channel model was proposed to analyze the influence of the combined effects of varying channel lengths, as well as applied drain and gate voltages. The proposed model was validated through TCAD simulation and by the fabricated SiC power MOSFETs. This model was applicable to MOSFETs with both symmetric and asymmetric channels considering various interface state density distributions. The influence of these factors on effective threshold voltage was also discussed considering variations in source contact resistance and channel doping concentration. Through the analysis of the model results, it was found that the interface states significantly impact the effective threshold voltage through different mechanisms while the SCEs are mitigated by the unsaturated interface states.

In a multiuser multiple-input multiple-output (MU-MIMO) downlink system, users are susceptible to interuser interference (IUI) because of data being simultaneously transmitted over the same time-frequency resources. Conventionally, precoding algorithms aim to eliminate the IUI. However, constructive interference (CI) precoding can achieve better error performance by exploiting the IUI. This article presents a high-throughput CI precoder. Design optimization across the algorithm and the architecture layers is conducted, reducing the complexity for multiplications by 81.6%. As the number of iterations for convergence varies, dynamic resource allocation is utilized to support each modulation mode with maximized utilization: time-multiplexing for the 4-QAM mode and parallel-processing for the 16-QAM mode. The proposed symbol updater also allows more efficient scheduling. As a proof of concept, a CI precoder chip that supports up to $16 \times $ MU-MIMO systems is designed based in a 40-nm CMOS technology. The performance gains at a bit error rate (BER) $= 10^{-4}$ are 10.7 and 12.5 dB for 4-QAM and 16-QAM, respectively, compared with conventional regularized zero-forcing (RZF) schemes. The precoder delivers a maximum throughput of 3.2 Gb/s at a clock frequency of 200 MHz for the $16 \times $ MU-MIMO configuration.

In this article, we study the performance of the gradient play algorithm for stochastic games (SGs), where each agent tries to maximize its own total discounted reward by making decisions independently based on current state information, which is shared between agents. Policies are directly parameterized by the probability of choosing a certain action at a given state. We show that Nash equilibria (NEs) and first-order stationary policies are equivalent in this setting, and give a local convergence rate around strict NEs. Furthermore, for a subclass of SGs called Markov potential games (which includes the setting with identical rewards as an important special case), we design a sample-based reinforcement learning algorithm and give a nonasymptotic global convergence rate analysis for both exact gradient play and our sample-based learning algorithm. Our result shows that the number of iterations to reach an $\epsilon$-NE scales linearly, instead of exponentially, with the number of agents. Local geometry and local stability are also considered, where we prove that strict NEs are local maxima of the total potential function and fully mixed NEs are saddle points.

Red phosphorus (RP) with a high theoretical specific capacity (2596 mA h g–1) and a moderate lithiation potential (∼0.7 V vs Li+/Li) holds promise as an anode material for lithium-ion batteries (LIBs), which still confronts discernible challenges, including low electrical conductivity, substantial volumetric expansion of 300%, and the shuttle effect induced by soluble lithium polyphosphide (LixPPs). Here, S-NRP@Ti3C2Txcomposites were in situ prepared through a phosphorus-amine-based method, wherein S-doped red phosphorus nanoparticles (S-NRP) grew and anchored on the crumpled Ti3C2Txnanosheets via Ti–O–P bonds, constructing a three-dimensional porous structure which provides fast channels for ion and electron transport and effectively buffers the volume expansion of RP. Interestingly, based on the results of adsorption experiments of polyphosphate and DFT calculation, Ti3C2Txwith abundant oxygen functional groups delivers a strong chemical adsorption effect on LixPPs, thus suppressing the shuttle effect and reducing irreversible capacity loss. Furthermore, S-doping improved the conductivity of red phosphorus nanoparticles, facilitating Li–P redox kinetics. Hence, the S-NRP@Ti3C2Txanode demonstrates outstanding rate performance (1824 and 1090 mA h g–1at 0.2 and 4.0 A g–1, respectively) and superior cycling performance (1401 mAh g–1after 500 cycles at 2.0 A g–1).

The construction of p–n heterojunctions is expected to be one of the effective means to improve gas sensitivity. In this research, p–n heterojunctions are successfully constructed by metal oxides derived from metal–organic frameworks (MOFs). MOFs-derived bimetallic Co3O4/SnO2microspheres are prepared by precipitation. Gas-sensing performance shows that the Co3O4/SnO2sensor exhibits an extremely high response (Ra/Rg= 641) to 20 ppm of n-butanol at 200 °C, which is 19 times that of pristine SnO2. It can detect n-butanol gas at low concentrations, has good selectivity to alcohol gas, and reduces the interference of benzene gas. The improved gas sensitivity can be attributed to the formation of a stable heterojunction between Co3O4and SnO2, resulting in a greater resistance change of Co3O4/SnO2. Co3O4/SnO2inherits the characteristic of high specific surface area of MOFs, which provides abundant sites for the reaction of the target gas and oxygen molecules. Finally, the gas-sensing mechanism of the Co3O4/SnO2-based sensor is discussed in detail.