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As a core driver for the high-tech enterprises, green technology innovation is crucial, even with high financial risk. Against this background, this paper empirically examines the impact of risk-taking on green technology innovation of high-tech enterprises, taking Chinese A-share listed companies from 2007 to 2020 as the research sample and considering the moderating effect of financial mismatch. Findings show the following: First, the effect of risk-taking on green technology innovation of high-tech enterprises is insignificant in most cases, and the inhibitory effect of financial mismatch is partly supported. Second, financial mismatch only counter-regulates the inhibitory effect of systematic risk-taking on the number of invention patents granted in the eastern sample. Third, the effect of risk-taking on green technology innovation is significantly heterogeneous in terms of property rights and regional heterogeneity, regardless of considering the moderating effect of financial mismatch or not. Finally, the policy implementations point out that the government should create a favorable investment environment, financial institutions should adjust the way of capital allocation, while high-tech enterprises should broaden the financing channels to enhance their risk-taking ability, and promote green technological innovation to achieve high-quality economic development.

With the rapid development of the current domestic science and technology, the introduction of modern Internet technology into the financial work field of enterprises, Internet technology and enterprise operation, Internet financial enterprises need to pay special attention to accounting problems and financial processing problems in the operation of Internet financial enterprises, this paper conducts in-depth research and analysis on the accounting problems of Internet finance, understands several deficiencies in actual operation, and puts forward a series of suggestions for improving response.

TiO2 is an important component of photoelectric devices. How to broaden the light absorption of TiO2 and accelerate the separation of photo-generated electrons and holes is the focus of the current research. Building heterojunction with narrow band gap semiconductor and TiO2 is one of the important measures to improve its photoelectric performance. We prepared BiVO4/TiO2 binary heterojunction by the simple hydrothermal method and analyzed the effect of BiVO4 precursor solution concentration on the microstructure and photoelectric performance of the heterojunction. BiVO4/TiO2 binary heterojunction can effectively improve the photoelectric performance of TiO2, and the transient current density reaches 85 μA/cm2. To further boost the photocurrent of BiVO4/TiO2, Bi2S3 was in situ grown on the heterojunction to form Bi2S3/BiVO4/TiO2 ternary heterojunction. The results show that the band gap of Bi2S3/BiVO4/TiO2 composites is significantly narrowed compared with that of TiO2. The light absorption has been expanded to the visible range, and the photogenerated current density is also greatly boosted (0.514 mA/cm2). This Bi2S3/BiVO4/TiO2 ternary heterojunction accelerates the separation of photo-carriers and improves the photoelectric performance of the device. The possible transport mechanism of photo-carriers in ternary heterojunction is analyzed. The current study provides an effective strategy for in situ construction of novel multicomponent heterojunction and provides a basis for the application of Bi2S3/BiVO4/TiO2 in the optoelectronic field.

The unique physical structure and abundant surface functional groups of MXene make the grafted organic molecules exhibit specific electrical and optical properties. This work reports the results of first-principles calculations to investigate the composite systems formed by different organic molecular monomers, namely acrylic acid (AA), acrylamide (AM), 1-aziridineethanol (1-AD) and glucose, and Ti3 C2 MXene saturated with different functional groups, namely -OH, -O and -F. The results show that the interaction between organic molecules and the MXene surface depends on the type of functional groups of the organic molecules, while the strength of the interaction is determined by the type of surface functional groups and the number of hydrogen bonds. The bare Ti3 C2 and Ti3 C2 (OH)2 can readily form strong chemical and hydrogen bonds with AA and AM molecules, leading to strong adsorption energy and a large amount of charge transfer, while the interaction between organic molecules and MXene saturated by -F or -O groups mainly exhibits physical interactions, accompanied by low adsorption energy and a small amount of charge transfer. This research provides theoretical guidance for the synthesis of high-performance MXene organic composite systems.

In practical flight process, the time-varying disturbances are often encountered by the space unmanned systems, and the attitude outputs of the space unmanned systems are required to stay in the predefined intervals. Moreover, the convergence process of the space unmanned systems has to be achieved in finite time, to complete the given tasks. However, most of the existing results are difficult to be applied to give consideration to the finite-time-convergence, the constrained outputs and the suppression for the time-varying disturbances simultaneously. To address this problem, in this article, we propose a novel fuzzy adaptive finite-time anti-disturbance control scheme for the space unmanned systems. The super-twisting disturbance observer, which possess the robust and finite-time disturbance estimation ability, has been utilized to suppress the time-varying disturbances. The nonlinear signal transformation technique has been introduced, transforming the constrained outputs into a novel unconstrained auxiliary variable, and the output constrained control issue becomes an equivalent bounded control problem. To achieve the finite-time convenience of the closed-loop space unmanned system, the fractional control laws have been designed, and an important lemma has been utilized to design the update laws of the adaptive parameters. Moreover, the fuzzy logic systems have been used to improve the robustness respect to the uncertainties. The contrastive simulation results have been provided, the finite-time control ability of the proposed method and the satisfactory estimation performance of the super-twisting disturbance observer can be observed.

Increasing nitrogen (N) deposition often tends to negatively impact the functions of belowground ectomycorrhizal networks, although the exact molecular mechanisms underlying this trait are still unclear. Here, we assess how the root-associated fungus Clitopilus hobsonii establishes an ectomycorrhiza-like association with its host tree Populus tomentosa and how this interaction is favored by organic N over mineral N. The establishment of a functional symbiosis in the presence of organic N promotes plant growth and the transfer of

The demand bound function (DBF) is a powerful abstraction to analyze the feasibility/schedulability of real-time tasks. Computing the DBF for expressive system models, such as graph-based tasks, is typically very expensive. In this article, we develop new techniques to drastically improve the DBF computation efficiency for a representative graph-based task model, digraph real-time tasks (DRT). First, we apply the well-known quick processor-demand analysis (QPA) technique, which was originally designed for simple sporadic tasks, to the analysis of DRT. The challenge is that existing analysis techniques of DRT have to compute the demand for each possible interval size, which is contradictory to the idea of QPA that aims to aggressively skip the computation for most interval sizes. To solve this problem, we develop a novel integer linear programming (ILP)-based analysis technique for DRT, to which we can apply QPA to significantly improve the analysis efficiency. Second, we improve the task utilization computation (a major step in DBF computation for DRT) efficiency from pseudo-polynomial complexity to polynomial complexity. Experiments show that our approach can improve the analysis efficiency by dozens of times.

Background Thermal ablation (TA), as an alternative to surgery, has shown some benefits in the treatment of papillary thyroid microcarcinoma (PTMC) patients, especially for those who are at high risk for surgery or refuse surgery. We performed a systematic review and meta-analysis to evaluate the efficiency, safety, and economy of TA, compared with those of routine surgery (RS), for the treatment of PTMC. Methods PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), Wanfang, and VIP databases were retrieved from inception to 10 January 2020 to identify relevant original studies on comparison of TA and RS for treatment of PTMC. The recurrence rate, recurrence-free survival (RFS), complication rate, operation time, postoperative length of stay, and cost during the perioperative period were extracted as main indices. The pooled standardized mean difference (SMD) or odds ratio (OR) with 95% confidence intervals (CI) were calculated and analyzed. Chi-square test and I2 statistic were applied to determine the heterogeneity among studies. The sensitivity analysis was applied to explore the origin of heterogeneity, and the publication bias was evaluated by Egger’s test. Results Seven retrospective studies with a total of 867 patients met the eligibility criteria and were included in the final meta-analysis. Our study demonstrated that TA showed significant reduction in complication with a pooled OR 0.24 (95% CI 0.13 to 0.43), postoperative length of stay with a pooled SMD −3.14 (95% CI −4.77 to −1.51) and cost during the perioperative period with a pooled SMD of −1.69 (95% CI −3.18 to −0.20). It also demonstrated that both TA and RS had similar pooled proportion of recurrence of OR 0.93 (95% CI 0.38 to 2.30) and recurrence-free survive (RFS). The sensitivity analysis showed that each included study had no significant effect on the results and the results were stable and reliable. The Egger’s test demonstrated publication bias was acceptable. Conclusions TA may not be oncologically inferior to RS, and it is a relatively safe and economical alternative for the treatment of PTMC.

Radar sensing will be integrated into the 6G communication system to support various applications. In this integrated sensing and communication system, a radar target may also be a communication channel scatterer. In this case, the radar and communication channels exhibit certain joint burst sparsity. We propose a two-stage joint pilot optimization, target detection and channel estimation scheme to exploit such joint burst sparsity and pilot beamforming gain to enhance detection/estimation performance. In Stage 1, the base station (BS) sends downlink pilots (DP) for initial target search, and the user sends uplink pilots (UP) for channel estimation. Then the BS performs joint target detection and channel estimation based on the reflected DP and received UP signals. In Stage 2, the BS exploits the prior information obtained in Stage 1 to optimize the DP signal to achieve beamforming gain and further refine the performance. A Turbo Sparse Bayesian inference algorithm is proposed for joint target detection and channel estimation in both stages. The pilot optimization problem in Stage 2 is a semi-definite programming with rank-1 constraints. By replacing the rank-1 constraint with a tight and smooth approximation, we propose an efficient pilot optimization algorithm based on the majorization-minimization method. Simulations verify the advantages of the proposed scheme., 30 pages, 8 figures, submitted to IEEE Transactions on Wireless Communications

Pancreatic cancer (PC) is a fatal tumor with high mortality. Pyroptosis plays a tumor suppressor role as a novel cell death. However, the influences of the pyroptosis-related lncRNAs (PRlncRNAs) on the prognosis and tumor microenvironment (TME) infiltration have not been fully studied in PC. Using coexpression analysis and univariate Cox regression analysis, we identified seventeen prognostic PRlncRNAs from The Cancer Genome Atlas (TCGA) dataset, which were all expressed differently in normal and tumor samples. A seven-PRlncRNA risk signature was constructed and validated using the least absolute shrinkage and selection operator (LASSO) regression. Furthermore, we verified its independence and created a nomogram to validate the clinical viability of the risk signature. We then identified its relationship with clinical factors and evaluated its values in TME infiltration, functional enrichment, tumor mutation, and therapeutic responses in PC. Lower ImmuneScore, ESTIMATEScore, and advanced tumor stage were connected with high-risk score. The low-risk group was characterized by better OS, elevated immune activation, and higher susceptibility of pazopanib and sunitinib. The high-risk group possessed a worse immune infiltration and poor survival, with higher tumor mutations and lapatinib and paclitaxel that may be better choices in this group. In conclusion, we developed an original seven-PRlncRNA risk signature to predict prognosis, TME infiltration, tumor mutation, and therapeutic options for PC patients.

Chiral metal-organic frameworks (CMOFs) served as chiral stationary phases (CSPs) show great potential in enantioseparation field. However, their performance improvement are still hindered by the difficult column packed and high back pressure due to the irregular morphology and broad size scope of CMOF particles. Here, the size and morphology of achiral Co-MOF-74 were effectively adjusted by controlling the synthetic route, temperature, the ratio of reactants and the amount of 2-methylimidazole (2-MI) at first. As a result, the uniformly spherical crystals in size of about 5 μm with good dispersion were obtained. Subsequently, a simple, green post-synthetic modification strategy was proposed for the fabrication of l-tyrosine functionalized Co-MOF-74, namely Co-MOF-74-L-Tyr in H

Herein, a rapid approach toward the size/morphology-controlled synthesis of [Cu(L-mal)(bipy)·2H2O] (CuLBH) was developed by adjusting the concentrations of 2-methylimidazole (2-MI) and copper ions. The chiral separation efficiency test indicated that the nano-diameter CuLBH exhibited better selective potential towards (±)-1-(1-naphthyl)ethanol (NE) by providing more fully exposed recognition sites. In order to further improve the selectivity for NE enantiomers and avoid the aggregation of MOF nanoparticles, the nanosized CuLBH-decorated carboxylated cellulose (CC) composite CC–CuLBH was designed by controlling the ratio of the solvent and Cu2+, which exhibited much higher enantioselectivity than those of pristine CC and even nano CuLBH.

As one of the most efficient electrochemical energy storage devices, the energy density of lithium-ion batteries (LIBs) has been extensively improved in the past several decades. However, with increased energy density, the safety risk of LIBs becomes higher too. The frequently occurred battery accidents worldwide remind us that safeness is a crucial requirement for LIBs, especially in environments with high safety concerns like airplanes and military platforms. It is generally recognized that the catastrophic thermal runaway (TR) event is the major cause of LIBs related accidents. Tremendous efforts have been devoted to coping with the TR concerns in LIBs, and thus enhance battery safety. This review first gives an introduction to the fundamentals of LIBs and the origins of safety issues. Then, the authors summarize the recent advances to improve the safety of LIBs with a unique focus on thermal-responsive and fire-resistant materials. Finally, a perspective is proposed to guide future research directions in this field. It is anticipated this review will stimulate inspiration and arouse extensive studies on further improvement in battery safety.

The unique physical structure and abundant surface functional groups of MXene make the grafted organic molecules exhibit specific electrical and optical properties. This work reports the results of first-principles calculations to investigate the composite systems formed by different organic molecular monomers, namely acrylic acid (AA), acrylamide (AM), 1-aziridineethanol (1-AD) and glucose, and Ti

Nowadays, the practical tasks of UAVs are becoming more and more complicated and diversified. In the practical flight process, the large-scale changes of the flight environment, the modeling errors, and the external disturbances may induce the instability of the UAV flight system. Meanwhile, the constraints of the UAV attitudes also have to be guaranteed during the flight process. However, most existing control methods still have limitations in handling the constraints and the multisource disturbances simultaneously. To address this problem, in this paper, we focus on the actual output tracking control for the UAV systems with full-state constraints and multisource disturbances. Firstly, a high-order tan-type barrier Lyapunov function (HOBLF) has been constructed for the UAV to maintain the full-state constraints. Secondly, by combining the adaptive backstepping technique and the fuzzy logic systems, the modeling errors and the unknown nonlinearities of the UAV attitude control system can be handled. Moreover, by properly constructing several adaptive laws, the time-varying disturbances existing in the UAV attitude control system can be suppressed. Finally, the full-state-constrained antidisturbance controller is formed, ensuring that the tracking error approaches arbitrarily to small neighborhood and does not violate the given constraints. The simulation results illustrate the feasibility and the advantages of the proposed method.

In the traditional DV-Hop location algorithm, the number of hops within the communication radius is counted as one hop. However, in the case of uneven distribution of nodes, this method will bring a large error to the calculation of hop distance. In order to solve the above problems, an improved DV-Hop location algorithm with multiple communication radius is proposed in this paper. Based on the multi-communication radius location algorithm, the method uses the cosine theorem to correct the hop number and estimated the average hop distance, and optimizes the estimated distance of the unknown node. The algorithm uses multiple communication radius to broadcast the position to obtain the minimum number of hops between the unknown node and the beacon node and adjusts the estimated hop distance by using the cosine theorem after estimating the good hop distance, and finally uses the trilateration method, or the maximum likelihood estimation method estimates the position coordinates. The experimental results show that compared with the traditional DV-Hop algorithm and DDV-Hop algorithm, the improved DV-Hop algorithm improves the positioning accuracy and reduces the average positioning error of the unknown nodes.

In this paper, a deep learning-based fault diagnosis framework is proposed to improve the fault diagnosis accuracy of system-level equipment such as condenser systems in nuclear power plants. The condenser system signals are non-vibrating, slowly time-varying, and multi-dimensional in nature. Therefore, in this paper, we propose a deep learning-based fault diagnosis framework, which adopts the idea of combining data warehouse modeling and deep learning fault diagnosis, and establishes the data set required for deep learning through accurate simulation modeling of typical condenser faults, so as to make full use of the feature extraction capability of deep learning under large-scale samples. Based on this, an end-to-end deep learning model is developed for accurate diagnosis of multiple condenser faults under multiple system conditions. Through the fault diagnosis experiments on the validation set data under various system conditions, the fault diagnosis accuracy is as high as 0.9584, which verifies the effectiveness of the proposed framework in fault diagnosis of system-level equipment.

The urban agglomeration polders type of flood control pattern is a general flood control pattern in the eastern plain area and some of the secondary river basins in China. A HEC-HMS model of Qinhuai River basin based on the flood control pattern was established for simulating basin runoff, examining the impact of urban agglomeration polders on flood events, and estimating the effects of urbanization on hydrological processes of the urban agglomeration polders in Qinhuai River basin. The results indicate that the urban agglomeration polders could increase the peak flow and flood volume. The smaller the scale of the flood, the more significant the influence of the polder was to the flood volume. The distribution of the city circle polder has no obvious impact on the flood volume, but has effect on the peak flow. The closer the polder is to basin output, the smaller the influence it has on peak flows. As the level of urbanization gradually improving of city circle polder, flood volumes and peak flows gradually increase compared to those with the current level of urbanization (the impervious rate was 20%). The potential change in flood volume and peak flow with increasing impervious rate shows a linear relationship.

In this paper, extreme precipitation spatial analog is examined as an alternative method to adapt extreme precipitation projections for use in urban hydrological studies. The idea for this method is that real climate records from some cities can serve as “analogs” that behave like potential future precipitation for other locations at small spatio-temporal scales. Extreme precipitation frequency quantiles of a 3.16 km 2 catchment in the Chicago area, computed using simulations from North American Regional Climate Change Assessment Program (NARCCAP) Regional Climate Models (RCMs) with L-moment method, were compared to National Oceanic and Atmospheric Administration (NOAA) Atlas 14 (NA14) quantiles at other cities. Variances in raw NARCCAP historical quantiles from different combinations of RCMs, General Circulation Models (GCMs), and remapping methods are much larger than those in NA14. The performance for NARCCAP quantiles tend to depend more on the RCMs than the GCMs, especially at durations less than 24-h. The uncertainties in bias-corrected future quantiles of NARCCAP are still large compared to those of NA14, and increase with rainfall duration. Results show that future 3-h and 30-day rainfall in Chicago will be similar to historical rainfall from Memphis, TN and Springfield, IL, respectively. This indicates that the spatial analog is potentially useful, but highlights the fact that the analogs may depend on the duration of the rainfall of interest.

Resistivity of Plane-film Energy Conversion Components is a key parameter to influence its resistance and explosive performance, and also it has important relations with the preparation of thin film technology, scale, structure and etc. In order to improve the design of Energy Conversion Components for MEMS Initiating Explosive Device, and reduce the design deviation of Energy Conversion Components in microscale, guarantee the design resistance and ignition performance of MEMS Initiating Explosive Device, this paper theoretically analyzed the influence factors of film resistivity in microscale, through the preparation of Al film and Ni-Cr film at different thickness with micro/nano, then obtain the film resistivity parameter of the typical metal under different thickness, and reveals the effect rule of the scale to the resistivity in microscale, at the same time we obtain the corresponding inflection point data.

Diamond-like carbon (DLC) filmare widely used in the infrared protection window, but their ability of anti-laser damage is insufficient. The common methods to improve the anti-laser ability of DLC films were summarized at first, then a new method which use the external electric field was proposed. Based on the standards ISO11254 of laser damage threshold, the damage morphology of DLC films with and without the bias field were compared. The results show that with the bias field, damage morphologies changes obviously under the same laser energy. According to the physical mechanism analysis, the photogenerated electrons of the films under the action of electric field drift speedy, the drift reduce the heat generated from the laser radiation area, then relayed the graphitization of the DLC films. This after-treated method will be a new method to improve DLC films’ anti-laser damage ability.

When detonation cords are used in explosive trains such as explosive circuits, the output performance can be obtained by destructive tests of matching samples from common production lots. In this paper the shockwave pressure testing method for Detonating Cords is studied. Two types of sensors are used to test the shockwave pressure. One is a thin film Mn-Cu sensor which is a standard testing method for output performance of explosive devices. The other sensor is a high pressure sensor with a microcircuit in it; this sensor can be used many times. The testing results are verified in the detonation equation.Copyright © 2008 by ASME