分子筛催化剂Ce-Cu-SSZ-13在与工业炉排烟温度一致的条件下具有卓越的选择性催化还原(Selective Catalytic Reduction,SCR)脱硝性能,将其涂覆于内含扩缩通道的蜂窝陶瓷表面制作高温复合SCR蓄热体,可实现烟气脱硝与余热回收设备一体化。...分子筛催化剂Ce-Cu-SSZ-13在与工业炉排烟温度一致的条件下具有卓越的选择性催化还原(Selective Catalytic Reduction,SCR)脱硝性能,将其涂覆于内含扩缩通道的蜂窝陶瓷表面制作高温复合SCR蓄热体,可实现烟气脱硝与余热回收设备一体化。为优化新型SCR蓄热体综合性能,以蓄热体长度(L)、扩张/收缩角(θ)和烟气流速(V)为设计变量,能量回收率(ERR)、脱硝效率(η)和烟气压力损失(ΔP)为目标函数,开展耦合蓄热式传热的SCR烟气脱硝Fluent数值模拟研究。根据模拟结果,采用响应面方法建立目标函数回归模型。在此基础上,采用多目标优化遗传算法NSGA-Ⅱ求得帕累托最优解集,使用基于熵权法(Entropy Weight Method,EWM)的熵权TOPSIS(Technique for Order Preference by Similarity to an Ideal Solution)法计算其与负理想解的相对接进度并以此确定最优解。方差分析验证回归模型的显著性,响应曲面分析则揭示了不同设计变量对目标函数的协同影响规律。结果表明,新型复合SCR蓄热体最佳设计变量为:L=717.57 mm,θ=12.19°和V=4.03 m/s,对应目标函数为ERR=68.13%,η=99.38%和ΔP=52.57 Pa。此时烟气出口温度约150℃,NO质量浓度为4.3 mg/m^(3)。另外,将烟气速度约束至5和6 m/s后发现最优解减小了扩张/收缩角,以防止蓄热体压力损失大幅增加。展开更多
In order to overcome the existing disadvantages of offline laser shock peening detection methods, an online detection method based on acoustic wave signals energy is provided. During the laser shock peening, an acoust...In order to overcome the existing disadvantages of offline laser shock peening detection methods, an online detection method based on acoustic wave signals energy is provided. During the laser shock peening, an acoustic emission sen- sor at a defined position is used to collect the acoustic wave signals that propagate in the air. The acoustic wave signal is sampled, stored, digitally filtered and analyzed by the online laser shock peening detection system. Then the system gets the acoustic wave signal energy to measure the quality of the laser shock peening by establishing the correspondence between the acoustic wave signal energy and the laser pulse energy. The surface residual stresses of the samples are measured by X-ray stress analysis instrument to verify the reliability. The results show that both the surface residual stress and acoustic wave signal energy are increased with the laser pulse energy, and their growth trends are consistent. Finally, the empirical formula between the surface residual stress and the acoustic wave signal energy is established by the cubic equation fitting, which will provide a theoretical basis for the real-time online detection of laser shock peening.展开更多
In response to the capabilities presented by the High-Intensity Heavy Ion Accelerator Facility(HIAF) and the Accelerator-Driven Subcritical System(Ci ADS), as well as the proposed Chinese Advanced Nuclear Physics Rese...In response to the capabilities presented by the High-Intensity Heavy Ion Accelerator Facility(HIAF) and the Accelerator-Driven Subcritical System(Ci ADS), as well as the proposed Chinese Advanced Nuclear Physics Research Facility(CNUF), we are assembling a consortium of experts in relevant disciplines, both domestically and internationally,to delineate high-precision physics experiments that leverage the state-of-the-art research environment afforded by CNUF.Our focus encompasses six primary domains of inquiry: hadron physics—including endeavors such as the super eta factory and investigations into light hadron structures;muon physics;neutrino physics;neutron physics;the testing of fundamental symmetries;and the exploration of quantum effects within nuclear physics, along with the utilization of vortex accelerators.We aim to foster a well-rounded portfolio of large, medium, and small-scale projects, thus unlocking new scientific avenues and optimizing the potential of the Huizhou large scientific facility. The aspiration for international leadership in scientific research will be a guiding principle in our strategic planning. This initiative will serve as a foundational reference for the Institute of Modern Physics in its strategic planning and goal-setting, ensuring alignment with its developmental objectives while striving to secure a competitive edge in technological advancement. Our ambition is to engage in substantive research within these realms of high-precision physics, to pursue groundbreaking discoveries, and to stimulate progress in China's nuclear physics landscape, positioning Huizhou as a preeminent global hub for advanced nuclear physics research.展开更多
This study systematically investigated the coupling effects of confiningpressure and strain rate on the dynamic strength of granite through dynamic triaxial compression tests.A dynamic strength criterion was developed...This study systematically investigated the coupling effects of confiningpressure and strain rate on the dynamic strength of granite through dynamic triaxial compression tests.A dynamic strength criterion was developed to incorporate these coupling effects for further analysis.Moreover,the research thoroughly revealed the underlying mechanism by which these coupling effects influencethe rock strength.The results revealed that both confiningpressure and strain rate significantly enhanced the dynamic strength of rock;however,a mutual inhibition effect emerged under their coupling.Specifically,as the confiningpressure increased,the strengthening effect of strain rate gradually diminished.Conversely,increasing the strain rate weakened the strengthening effect of confiningpressure.The proposed strength criterion successfully predicted rock strength under various confiningpressures(0-225 MPa)and strain rates(10^(-6)-600 s^(-1)).It achieved an average prediction error of only 8.3%,which represents a 65%improvement in accuracy compared to models that consider confiningpressure and strain rate effects independently.At the micro-mechanism level,increasing confiningpressure and strain rate promoted crack propagation in a transgranular(TG)mode,thereby enhancing the overall rock strength.However,under the coupling effects,the interference and interaction of TG cracks weakened the overall strengthening effect.This indicated that the competitive interaction between confiningpressure and strain rate during crack propagation constitutes the intrinsic mechanism underlying their mutual inhibitory effect on rock strength.This study provides a more accurate theoretical basis for understanding the dynamic responses of rocks and contributes valuable insights for disaster prevention and control in deep rock engineering projects.展开更多
Government credibility is an important asset of contemporary national governance, an important criterion for evaluating government legitimacy, and a key factor in measuring the effectiveness of government governance. ...Government credibility is an important asset of contemporary national governance, an important criterion for evaluating government legitimacy, and a key factor in measuring the effectiveness of government governance. In recent years, researchers’ research on government credibility has mostly focused on exploring theories and mechanisms, with little empirical research on this topic. This article intends to apply variable selection models in the field of social statistics to the issue of government credibility, in order to achieve empirical research on government credibility and explore its core influencing factors from a statistical perspective. Specifically, this article intends to use four regression-analysis-based methods and three random-forest-based methods to study the influencing factors of government credibility in various provinces in China, and compare the performance of these seven variable selection methods in different dimensions. The research results show that there are certain differences in simplicity, accuracy, and variable importance ranking among different variable selection methods, which present different importance in the study of government credibility issues. This study provides a methodological reference for variable selection models in the field of social science research, and also offers a multidimensional comparative perspective for analyzing the influencing factors of government credibility.展开更多
Microbiologically influenced corrosion(MIC) is an unavoidable problem in several industries. Copper(Cu)and its alloys are widely used engineering materials. However, MIC of Cu remains a persistent challenge to their p...Microbiologically influenced corrosion(MIC) is an unavoidable problem in several industries. Copper(Cu)and its alloys are widely used engineering materials. However, MIC of Cu remains a persistent challenge to their performance and functional lifetime under aggressive environments. This study investigated nanosecond pulsed laser processing(LP), which may enhance the corrosion resistance of Cu. The microstructural evolution and corrosion behavior of LP-Cu in the presence of sulfate-reducing bacteria(SRB) were evaluated. Typical deformation-induced microstructural features of high-density dislocations were analyzed on the top surface of LP-Cu coupon. Electrochemical measurements suggested that LP-Cu coupons exhibited better corrosion resistance in SRB-inoculated solution compared with their original counterpart. The enhanced corrosion resistance by LP primarily resulted from the combined influences of compressive residual stress and work hardening in the surface. However, overlap percentage played a key role in improving corrosion resistance. LP produced optimal corrosion resistance at 50% overlap. Therefore, this study introduces a unique and an option for anticorrosion control in manufacturing processes and potentially implements it onto other materials to improve its microbial corrosion resistance through LP.展开更多
Anther dehiscence controls optimal interaction between pollen and stigma,thereby determining the successful sexual reproduction.The regulators or mechanisms of this process remain elusive.Here,two CRISPR/Cas9 mutants ...Anther dehiscence controls optimal interaction between pollen and stigma,thereby determining the successful sexual reproduction.The regulators or mechanisms of this process remain elusive.Here,two CRISPR/Cas9 mutants of a rice exocyst subunit gene SEC3A,sec3a-1 and sec3a-2,showed anther indehiscence at anthesis and male sterility at maturity.Pollen viability and germination in the mutants were partly defective,whereas their female gametes undergone a normal development.Hybrid or self-pollinated seeds could be produced by artificial pollination,suggesting potential use of a weak sec3a mutant as a female line during hybrid breeding.SEC3A is widely expressed in various tissues,including anther walls.Further results showed an excessive IAA accumulation and no endothecium lignification in sec3a-1/2 anthers.Our findings suggest that SEC3A appears to regulate anther dehiscence by modulating auxin signaling,providing insights into regulation of anther dehiscence and function of exocyst in plants.展开更多
A dynamic plant architecture is the basis of plant adaptation to changing environments.Although many genes regulating leaf rolling have been identified,genes directly associated with water homeostasis are largely unkn...A dynamic plant architecture is the basis of plant adaptation to changing environments.Although many genes regulating leaf rolling have been identified,genes directly associated with water homeostasis are largely unknown.Here,we isolated a rice mutant,dynamic leaf rolling 1(dlr1),characterized by‘leaf unfolding in the morning-leaf rolling at noon-leaf unfolding in the evening’during a sunny day.Water content was decreased in rolled leaves and water sprayed on leaves caused reopening,indicating that in vivo water deficiency induced the leaf rolling.Map-based cloning and expression tests demonstrated that an A1400G single base mutation in Oryza sativa Polygalacturonase 1(OsPG1)/PHOTO-SENSITIVE LEAF ROLLING 1(PSL1)was responsible for the dynamic leaf rolling phenotype in the dlr1 mutant.OsPG1 encodes a polygalacturonase,one of the main enzymes that degrade demethylesterified homogalacturonans in plant cell walls.OsPG1 was constitutively expressed in various tissues and was enriched in stomata.Mutants of the OsPG1 gene exhibited defects in stomatal closure and decreased stomatal density,leading to reduced transpiration and excessive water loss under specific conditions,but had normal root development.Further analysis revealed that mutation of OsPG1 led to reduced pectinase activity in the leaves and increased demethylesterified homogalacturonans in guard cells.Our findings reveal a mechanism by which OsPG1 modulates water homeostasis to control dynamic leaf rolling,providing insights for plants to adapt to environmental variation.展开更多
Alzheimer's disease(AD)is a chronic and progressive neurodegenerative disorder with long preclinical and prodromal phases in older people.Molecular imaging is a promising approach for noninvasive in vivo identific...Alzheimer's disease(AD)is a chronic and progressive neurodegenerative disorder with long preclinical and prodromal phases in older people.Molecular imaging is a promising approach for noninvasive in vivo identification and tracking pathophysiological changes.In particular,nuclear neuroimaging in AD has extended beyond traditional evaluation of brain perfusion and glucose metabolism,and has achieved substantial progress over the past 2 decades.To gain a comprehensive understanding of nuclear neuroimaging with different targets in the brain,this review provides an overview of the literature on the current status and recent progress of the development of radioligands for definitive and differential diagnosis of AD.展开更多
In basketball, each player’s skill level is the key to a team’s success or failure, the skill level is affected by many personal and environmental factors. A physics-informed AI statistics has become extremely impor...In basketball, each player’s skill level is the key to a team’s success or failure, the skill level is affected by many personal and environmental factors. A physics-informed AI statistics has become extremely important. In this article, a complex non-linear process is considered by taking into account the average points per game of each player, playing time, shooting percentage, and others. This physics-informed statistics is to construct a multiple linear regression model with physics-informed neural networks. Based on the official data provided by the American Basketball League, and combined with specific methods of R program analysis, the regression model affecting the player’s average points per game is verified, and the key factors affecting the player’s average points per game are finally elucidated. The paper provides a novel window for coaches to make meaningful in-game adjustments to team members.展开更多
The sixth-generation(6G)mobile network implements the social vision of digital twins and ubiquitous intelligence.Contrary to the fifth-generation(5G)mobile network that focuses only on communications,6G mobile network...The sixth-generation(6G)mobile network implements the social vision of digital twins and ubiquitous intelligence.Contrary to the fifth-generation(5G)mobile network that focuses only on communications,6G mobile networks must natively support new capabilities such as sensing,computing,artificial intelligence(AI),big data,and security while facilitating Everything as a Service.Although 5G mobile network deployment has demonstrated that network automation and intelligence can simplify network operation and maintenance(O&M),the addition of external functionalities has resulted in low service efficiency and high operational costs.In this study,a technology framework for a 6G autonomous radio access network(RAN)is proposed to achieve a high-level network autonomy that embraces the design of native cloud,native AI,and network digital twin(NDT).First,a service-based architecture is proposed to re-architect the protocol stack of RAN,which flexibly orchestrates the services and functions on demand as well as customizes them into cloud-native services.Second,a native AI framework is structured to provide AI support for the diverse use cases of network O&M by orchestrating communications,AI models,data,and computing power demanded by AI use cases.Third,a digital twin network is developed as a virtual environment for the training,pre-validation,and tuning of AI algorithms and neural networks,avoiding possible unexpected losses of the network O&M caused by AI applications.The combination of native AI and NDT can facilitate network autonomy by building closed-loop management and optimization for RAN.展开更多
We present the first lattice result of the near threshold Λ_(c)Λ_(c)scattering with I(J^(P)) = 0(0^(+)). The calculation is performed on two N_(f)= 2 + 1 Wilson-Clover ensembles with pion mass m_(π)~ 303 MeV and la...We present the first lattice result of the near threshold Λ_(c)Λ_(c)scattering with I(J^(P)) = 0(0^(+)). The calculation is performed on two N_(f)= 2 + 1 Wilson-Clover ensembles with pion mass m_(π)~ 303 MeV and lattice spacing a = 0.07746 fm. Lüscher's finite volume method is utilized to extract the scattering parameters from the finitevolume spectrum. The coupled channel Ξ_(cc)N is ignored in the scattering analysis based on the observation that the energy levels computed from the Λ_(c)Λ_(c)and Ξ_(cc) N operators do not mix. The Σ_(c)Σ_(c) channel is not included either since the energy range explored in this study is well below its threshold. Our results indicate that the interaction in the Λ_(c)Λ_(c)single channel is repulsive, and the scattering length is determined to be a_(0)=-0.21(4)(8) fm, where the first error is statistical and the second is systematic.展开更多
Lepton scattering is an established ideal tool for studying inner structure of small particles such as nucleons as well as nuclei.As a future high energy nuclear physics project,an Electron-ion collider in China(EicC)...Lepton scattering is an established ideal tool for studying inner structure of small particles such as nucleons as well as nuclei.As a future high energy nuclear physics project,an Electron-ion collider in China(EicC)has been proposed.It will be constructed based on an upgraded heavy-ion accelerator,High Intensity heavy-ion Accelerator Facility(HIAF)which is currently under construction,together with a new electron ring.The proposed collider will provide highly polarized electrons(with a po-larization of 80%)and protons(with a polarization of 70%)with variable center of mass energies from 15 to 20 GeV and the luminosity of(2–3)×1033 cm^(−2)·s^(−1).Polarized deuterons and Helium-3,as well as unpolarized ion beams from Carbon to Uranium,will be also available at the EicC.The main foci of the EicC will be precision measurements of the structure of the nucleon in the sea quark region,including 3D tomography of nucleon;the partonic structure of nuclei and the parton interaction with the nuclear environment;the exotic states,especially those with heavy flavor quark contents.In addition,issues fundamental to understanding the origin of mass could be addressed by measurements of heavy quarkonia near-threshold production at the EicC.In order to achieve the above-mentioned physics goals,a hermetical detector system will be constructed with cutting-edge technologies.This document is the result of collective contributions and valuable inputs from experts across the globe.The EicC physics program complements the ongoing scientific programs at the Jefferson Laboratory and the future EIC project in the United States.The success of this project will also advance both nuclear and particle physics as well as accelerator and detector technology in China.展开更多
We explain the W-boson mass anomaly by introducing an SU(2)_(L)scalar multiplet with general isospin and hypercharge{in the case without its vacuum expectation value}.It is shown that the dominant contribution from th...We explain the W-boson mass anomaly by introducing an SU(2)_(L)scalar multiplet with general isospin and hypercharge{in the case without its vacuum expectation value}.It is shown that the dominant contribution from the scalar multiplet to the W-boson mass arises at the one-loop level,which can be expressed in terms of the electroweak(EW)oblique parameters T and S at leading order.We first rederive the general formulae of T and S induced by a scalar multiplet of EW charges,confirming the results in literature.We then study several specific examples of great phenomenological interest by applying these general expressions.As a result,it is found that the model with a scalar multiplet in an SU(2)_(L)real representation with Y=0 cannot generate the required M_(W)correction because it leads to vanishing values of T and S.However,the cases with scalars in a complex representation under SU(2)_(L)with a general hypercharge can explain the M_(W)excess observed by CDF-Ⅱowing to nonzero T and S.We further consider the strong constraints from the perturbativity and EW global fit of the precision data and vary the isospin representation and hypercharge of the additional scalar multiplet to assess the extent of the model to solve the W-boson mass anomaly.It turns out that these constraints play important roles in setting limits on the model parameter space.We also briefly describe the collider signatures of the extra scalar multiplet,especially when it contains long-lived,heavy,highly charged states.展开更多
Deep learning enables real-time resource allocation for ultra-reliable and low-latency communications(URLLC),one of the major use cases in the next-generation cellular networks.Yet the high training complexity and wea...Deep learning enables real-time resource allocation for ultra-reliable and low-latency communications(URLLC),one of the major use cases in the next-generation cellular networks.Yet the high training complexity and weak generalization ability of neural networks impede the practical use of the learning-based methods in dynamic wireless environments.To overcome these obstacles,we propose a parameter generation network(PGN)to efficiently learn bandwidth and power allocation policies in URLLC.The PGN consists of two types of fully-connected neural networks(FNNs).One is a policy network,which is used to learn a resource allocation policy or a Lagrangian multiplier function.The other type of FNNs are hypernetworks,which are designed to learn the weight matrices and bias vectors of the policy network.Only the hypernetworks require training.Using the well-trained hypernetworks,the policy network is generated through forward propagation in the test phase.By introducing a simple data processing,the hypernetworks can well learn the weight matrices and bias vectors by inputting their indices,resulting in low training cost.Simulation results demonstrate that the learned bandwidth and power allocation policies by the PGNs perform very close to a numerical algorithm.Moreover,the PGNs can be well generalized to the number of users and wireless channels,and are with significantly lower memory costs,fewer training samples,and shorter training time than the traditional learning-based methods.展开更多
文摘分子筛催化剂Ce-Cu-SSZ-13在与工业炉排烟温度一致的条件下具有卓越的选择性催化还原(Selective Catalytic Reduction,SCR)脱硝性能,将其涂覆于内含扩缩通道的蜂窝陶瓷表面制作高温复合SCR蓄热体,可实现烟气脱硝与余热回收设备一体化。为优化新型SCR蓄热体综合性能,以蓄热体长度(L)、扩张/收缩角(θ)和烟气流速(V)为设计变量,能量回收率(ERR)、脱硝效率(η)和烟气压力损失(ΔP)为目标函数,开展耦合蓄热式传热的SCR烟气脱硝Fluent数值模拟研究。根据模拟结果,采用响应面方法建立目标函数回归模型。在此基础上,采用多目标优化遗传算法NSGA-Ⅱ求得帕累托最优解集,使用基于熵权法(Entropy Weight Method,EWM)的熵权TOPSIS(Technique for Order Preference by Similarity to an Ideal Solution)法计算其与负理想解的相对接进度并以此确定最优解。方差分析验证回归模型的显著性,响应曲面分析则揭示了不同设计变量对目标函数的协同影响规律。结果表明,新型复合SCR蓄热体最佳设计变量为:L=717.57 mm,θ=12.19°和V=4.03 m/s,对应目标函数为ERR=68.13%,η=99.38%和ΔP=52.57 Pa。此时烟气出口温度约150℃,NO质量浓度为4.3 mg/m^(3)。另外,将烟气速度约束至5和6 m/s后发现最优解减小了扩张/收缩角,以防止蓄热体压力损失大幅增加。
基金This study was co-supported by National Natural Science Foundation of China （51501219）, National Key Development Program of China （2016YFB 1192704）, NSFC -Liaoning Province United Foundation （U 1608259） and National Key Technology Research and Development Program of the Ministry of Science and Technology of China （2015BAFOBBO 1-01）.
文摘In order to overcome the existing disadvantages of offline laser shock peening detection methods, an online detection method based on acoustic wave signals energy is provided. During the laser shock peening, an acoustic emission sen- sor at a defined position is used to collect the acoustic wave signals that propagate in the air. The acoustic wave signal is sampled, stored, digitally filtered and analyzed by the online laser shock peening detection system. Then the system gets the acoustic wave signal energy to measure the quality of the laser shock peening by establishing the correspondence between the acoustic wave signal energy and the laser pulse energy. The surface residual stresses of the samples are measured by X-ray stress analysis instrument to verify the reliability. The results show that both the surface residual stress and acoustic wave signal energy are increased with the laser pulse energy, and their growth trends are consistent. Finally, the empirical formula between the surface residual stress and the acoustic wave signal energy is established by the cubic equation fitting, which will provide a theoretical basis for the real-time online detection of laser shock peening.
基金supported by the National Natural Science Foundation of China (Grant No.12075326)the Guangdong Basic and Applied Basic Research Foundation (Grant No.2025A1515010669)+2 种基金the Natural Science Foundation of Guangzhou (Grant No.2024A04J6243)the Fundamental Research Funds for the Central Universities in Sun Yat-sen University (No.23xkjc017)the Innovation Training Program for bachelor students in Sun Yat-sen University。
文摘In response to the capabilities presented by the High-Intensity Heavy Ion Accelerator Facility(HIAF) and the Accelerator-Driven Subcritical System(Ci ADS), as well as the proposed Chinese Advanced Nuclear Physics Research Facility(CNUF), we are assembling a consortium of experts in relevant disciplines, both domestically and internationally,to delineate high-precision physics experiments that leverage the state-of-the-art research environment afforded by CNUF.Our focus encompasses six primary domains of inquiry: hadron physics—including endeavors such as the super eta factory and investigations into light hadron structures;muon physics;neutrino physics;neutron physics;the testing of fundamental symmetries;and the exploration of quantum effects within nuclear physics, along with the utilization of vortex accelerators.We aim to foster a well-rounded portfolio of large, medium, and small-scale projects, thus unlocking new scientific avenues and optimizing the potential of the Huizhou large scientific facility. The aspiration for international leadership in scientific research will be a guiding principle in our strategic planning. This initiative will serve as a foundational reference for the Institute of Modern Physics in its strategic planning and goal-setting, ensuring alignment with its developmental objectives while striving to secure a competitive edge in technological advancement. Our ambition is to engage in substantive research within these realms of high-precision physics, to pursue groundbreaking discoveries, and to stimulate progress in China's nuclear physics landscape, positioning Huizhou as a preeminent global hub for advanced nuclear physics research.
基金financiallysupported by the National Natural Science Foundation of China(Grant No.42577209)the Natural Science Foundation of Jiangsu Province(Grant No.BK20241489)the Open Research Fund of State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences(Grant No.SKLGME023009).
文摘This study systematically investigated the coupling effects of confiningpressure and strain rate on the dynamic strength of granite through dynamic triaxial compression tests.A dynamic strength criterion was developed to incorporate these coupling effects for further analysis.Moreover,the research thoroughly revealed the underlying mechanism by which these coupling effects influencethe rock strength.The results revealed that both confiningpressure and strain rate significantly enhanced the dynamic strength of rock;however,a mutual inhibition effect emerged under their coupling.Specifically,as the confiningpressure increased,the strengthening effect of strain rate gradually diminished.Conversely,increasing the strain rate weakened the strengthening effect of confiningpressure.The proposed strength criterion successfully predicted rock strength under various confiningpressures(0-225 MPa)and strain rates(10^(-6)-600 s^(-1)).It achieved an average prediction error of only 8.3%,which represents a 65%improvement in accuracy compared to models that consider confiningpressure and strain rate effects independently.At the micro-mechanism level,increasing confiningpressure and strain rate promoted crack propagation in a transgranular(TG)mode,thereby enhancing the overall rock strength.However,under the coupling effects,the interference and interaction of TG cracks weakened the overall strengthening effect.This indicated that the competitive interaction between confiningpressure and strain rate during crack propagation constitutes the intrinsic mechanism underlying their mutual inhibitory effect on rock strength.This study provides a more accurate theoretical basis for understanding the dynamic responses of rocks and contributes valuable insights for disaster prevention and control in deep rock engineering projects.
文摘Government credibility is an important asset of contemporary national governance, an important criterion for evaluating government legitimacy, and a key factor in measuring the effectiveness of government governance. In recent years, researchers’ research on government credibility has mostly focused on exploring theories and mechanisms, with little empirical research on this topic. This article intends to apply variable selection models in the field of social statistics to the issue of government credibility, in order to achieve empirical research on government credibility and explore its core influencing factors from a statistical perspective. Specifically, this article intends to use four regression-analysis-based methods and three random-forest-based methods to study the influencing factors of government credibility in various provinces in China, and compare the performance of these seven variable selection methods in different dimensions. The research results show that there are certain differences in simplicity, accuracy, and variable importance ranking among different variable selection methods, which present different importance in the study of government credibility issues. This study provides a methodological reference for variable selection models in the field of social science research, and also offers a multidimensional comparative perspective for analyzing the influencing factors of government credibility.
基金financially supported by the National Science Foundation of China (Nos. 51871228, 51771213 and 51471176)。
文摘Microbiologically influenced corrosion(MIC) is an unavoidable problem in several industries. Copper(Cu)and its alloys are widely used engineering materials. However, MIC of Cu remains a persistent challenge to their performance and functional lifetime under aggressive environments. This study investigated nanosecond pulsed laser processing(LP), which may enhance the corrosion resistance of Cu. The microstructural evolution and corrosion behavior of LP-Cu in the presence of sulfate-reducing bacteria(SRB) were evaluated. Typical deformation-induced microstructural features of high-density dislocations were analyzed on the top surface of LP-Cu coupon. Electrochemical measurements suggested that LP-Cu coupons exhibited better corrosion resistance in SRB-inoculated solution compared with their original counterpart. The enhanced corrosion resistance by LP primarily resulted from the combined influences of compressive residual stress and work hardening in the surface. However, overlap percentage played a key role in improving corrosion resistance. LP produced optimal corrosion resistance at 50% overlap. Therefore, this study introduces a unique and an option for anticorrosion control in manufacturing processes and potentially implements it onto other materials to improve its microbial corrosion resistance through LP.
基金supported by the Science Fund for Creative Research Groups of the National Natural Science Foundation of China(32171970)the Chongqing Outstanding Scientists Project(cstc2022ycjh-bgzxm0073)the Natural Science Foundation of Chongqing,China(cstc2021jcyj-cxttX0004)。
文摘Anther dehiscence controls optimal interaction between pollen and stigma,thereby determining the successful sexual reproduction.The regulators or mechanisms of this process remain elusive.Here,two CRISPR/Cas9 mutants of a rice exocyst subunit gene SEC3A,sec3a-1 and sec3a-2,showed anther indehiscence at anthesis and male sterility at maturity.Pollen viability and germination in the mutants were partly defective,whereas their female gametes undergone a normal development.Hybrid or self-pollinated seeds could be produced by artificial pollination,suggesting potential use of a weak sec3a mutant as a female line during hybrid breeding.SEC3A is widely expressed in various tissues,including anther walls.Further results showed an excessive IAA accumulation and no endothecium lignification in sec3a-1/2 anthers.Our findings suggest that SEC3A appears to regulate anther dehiscence by modulating auxin signaling,providing insights into regulation of anther dehiscence and function of exocyst in plants.
基金This work was supported by the Postgraduate Research Innovation Project of Chongqing(CYS23217)Chongqing Modern Agricultural Industry Technology System(CQMAITS202301)+1 种基金the Science Fund for Creative Research Groups of the Natural Science Foundation of Chongqing,China(cstc2021jcyj-cxttX0004)Natural Science Foundation of Chongqing(2023NSCQ-BHX0281).
文摘A dynamic plant architecture is the basis of plant adaptation to changing environments.Although many genes regulating leaf rolling have been identified,genes directly associated with water homeostasis are largely unknown.Here,we isolated a rice mutant,dynamic leaf rolling 1(dlr1),characterized by‘leaf unfolding in the morning-leaf rolling at noon-leaf unfolding in the evening’during a sunny day.Water content was decreased in rolled leaves and water sprayed on leaves caused reopening,indicating that in vivo water deficiency induced the leaf rolling.Map-based cloning and expression tests demonstrated that an A1400G single base mutation in Oryza sativa Polygalacturonase 1(OsPG1)/PHOTO-SENSITIVE LEAF ROLLING 1(PSL1)was responsible for the dynamic leaf rolling phenotype in the dlr1 mutant.OsPG1 encodes a polygalacturonase,one of the main enzymes that degrade demethylesterified homogalacturonans in plant cell walls.OsPG1 was constitutively expressed in various tissues and was enriched in stomata.Mutants of the OsPG1 gene exhibited defects in stomatal closure and decreased stomatal density,leading to reduced transpiration and excessive water loss under specific conditions,but had normal root development.Further analysis revealed that mutation of OsPG1 led to reduced pectinase activity in the leaves and increased demethylesterified homogalacturonans in guard cells.Our findings reveal a mechanism by which OsPG1 modulates water homeostasis to control dynamic leaf rolling,providing insights for plants to adapt to environmental variation.
基金The Fundamental Research Funds for the Central Universities,and the Higher Education Discipline Innovation Project,Grant/Award Number:B18035National Natural Science Foundation of Sichuan Province of China,Grant/Award Number:2023NSFSC1721。
文摘Alzheimer's disease(AD)is a chronic and progressive neurodegenerative disorder with long preclinical and prodromal phases in older people.Molecular imaging is a promising approach for noninvasive in vivo identification and tracking pathophysiological changes.In particular,nuclear neuroimaging in AD has extended beyond traditional evaluation of brain perfusion and glucose metabolism,and has achieved substantial progress over the past 2 decades.To gain a comprehensive understanding of nuclear neuroimaging with different targets in the brain,this review provides an overview of the literature on the current status and recent progress of the development of radioligands for definitive and differential diagnosis of AD.
文摘In basketball, each player’s skill level is the key to a team’s success or failure, the skill level is affected by many personal and environmental factors. A physics-informed AI statistics has become extremely important. In this article, a complex non-linear process is considered by taking into account the average points per game of each player, playing time, shooting percentage, and others. This physics-informed statistics is to construct a multiple linear regression model with physics-informed neural networks. Based on the official data provided by the American Basketball League, and combined with specific methods of R program analysis, the regression model affecting the player’s average points per game is verified, and the key factors affecting the player’s average points per game are finally elucidated. The paper provides a novel window for coaches to make meaningful in-game adjustments to team members.
基金supported by the National Key Research and Development Program of China(No.2024YFE0200600)。
文摘The sixth-generation(6G)mobile network implements the social vision of digital twins and ubiquitous intelligence.Contrary to the fifth-generation(5G)mobile network that focuses only on communications,6G mobile networks must natively support new capabilities such as sensing,computing,artificial intelligence(AI),big data,and security while facilitating Everything as a Service.Although 5G mobile network deployment has demonstrated that network automation and intelligence can simplify network operation and maintenance(O&M),the addition of external functionalities has resulted in low service efficiency and high operational costs.In this study,a technology framework for a 6G autonomous radio access network(RAN)is proposed to achieve a high-level network autonomy that embraces the design of native cloud,native AI,and network digital twin(NDT).First,a service-based architecture is proposed to re-architect the protocol stack of RAN,which flexibly orchestrates the services and functions on demand as well as customizes them into cloud-native services.Second,a native AI framework is structured to provide AI support for the diverse use cases of network O&M by orchestrating communications,AI models,data,and computing power demanded by AI use cases.Third,a digital twin network is developed as a virtual environment for the training,pre-validation,and tuning of AI algorithms and neural networks,avoiding possible unexpected losses of the network O&M caused by AI applications.The combination of native AI and NDT can facilitate network autonomy by building closed-loop management and optimization for RAN.
基金Supported by NSFC (12293060, 12293061, 12293063, 12175279, 12435002, 12322503, 12175239)the Strategic Priority Research Program of the Chinese Academy of Sciences with (XDB34030301)+1 种基金Guangdong Major Project of Basic and Applied Basic Research (2020B0301030008)the Science and Education Integration Young Faculty Project of University of Chinese Academy of Sciences (YSBR-101)。
文摘We present the first lattice result of the near threshold Λ_(c)Λ_(c)scattering with I(J^(P)) = 0(0^(+)). The calculation is performed on two N_(f)= 2 + 1 Wilson-Clover ensembles with pion mass m_(π)~ 303 MeV and lattice spacing a = 0.07746 fm. Lüscher's finite volume method is utilized to extract the scattering parameters from the finitevolume spectrum. The coupled channel Ξ_(cc)N is ignored in the scattering analysis based on the observation that the energy levels computed from the Λ_(c)Λ_(c)and Ξ_(cc) N operators do not mix. The Σ_(c)Σ_(c) channel is not included either since the energy range explored in this study is well below its threshold. Our results indicate that the interaction in the Λ_(c)Λ_(c)single channel is repulsive, and the scattering length is determined to be a_(0)=-0.21(4)(8) fm, where the first error is statistical and the second is systematic.
文摘Lepton scattering is an established ideal tool for studying inner structure of small particles such as nucleons as well as nuclei.As a future high energy nuclear physics project,an Electron-ion collider in China(EicC)has been proposed.It will be constructed based on an upgraded heavy-ion accelerator,High Intensity heavy-ion Accelerator Facility(HIAF)which is currently under construction,together with a new electron ring.The proposed collider will provide highly polarized electrons(with a po-larization of 80%)and protons(with a polarization of 70%)with variable center of mass energies from 15 to 20 GeV and the luminosity of(2–3)×1033 cm^(−2)·s^(−1).Polarized deuterons and Helium-3,as well as unpolarized ion beams from Carbon to Uranium,will be also available at the EicC.The main foci of the EicC will be precision measurements of the structure of the nucleon in the sea quark region,including 3D tomography of nucleon;the partonic structure of nuclei and the parton interaction with the nuclear environment;the exotic states,especially those with heavy flavor quark contents.In addition,issues fundamental to understanding the origin of mass could be addressed by measurements of heavy quarkonia near-threshold production at the EicC.In order to achieve the above-mentioned physics goals,a hermetical detector system will be constructed with cutting-edge technologies.This document is the result of collective contributions and valuable inputs from experts across the globe.The EicC physics program complements the ongoing scientific programs at the Jefferson Laboratory and the future EIC project in the United States.The success of this project will also advance both nuclear and particle physics as well as accelerator and detector technology in China.
基金Supported in part by the National Key Research and Development Program of China(2021YFC2203003,2020YFC2201501)the National Natural Science Foundation of China(NSFC)(12005254,12147103)。
文摘We explain the W-boson mass anomaly by introducing an SU(2)_(L)scalar multiplet with general isospin and hypercharge{in the case without its vacuum expectation value}.It is shown that the dominant contribution from the scalar multiplet to the W-boson mass arises at the one-loop level,which can be expressed in terms of the electroweak(EW)oblique parameters T and S at leading order.We first rederive the general formulae of T and S induced by a scalar multiplet of EW charges,confirming the results in literature.We then study several specific examples of great phenomenological interest by applying these general expressions.As a result,it is found that the model with a scalar multiplet in an SU(2)_(L)real representation with Y=0 cannot generate the required M_(W)correction because it leads to vanishing values of T and S.However,the cases with scalars in a complex representation under SU(2)_(L)with a general hypercharge can explain the M_(W)excess observed by CDF-Ⅱowing to nonzero T and S.We further consider the strong constraints from the perturbativity and EW global fit of the precision data and vary the isospin representation and hypercharge of the additional scalar multiplet to assess the extent of the model to solve the W-boson mass anomaly.It turns out that these constraints play important roles in setting limits on the model parameter space.We also briefly describe the collider signatures of the extra scalar multiplet,especially when it contains long-lived,heavy,highly charged states.
基金supported by the Key Project of National Natural Science Foundation of China(NSFC)under Grant 61731002.
文摘Deep learning enables real-time resource allocation for ultra-reliable and low-latency communications(URLLC),one of the major use cases in the next-generation cellular networks.Yet the high training complexity and weak generalization ability of neural networks impede the practical use of the learning-based methods in dynamic wireless environments.To overcome these obstacles,we propose a parameter generation network(PGN)to efficiently learn bandwidth and power allocation policies in URLLC.The PGN consists of two types of fully-connected neural networks(FNNs).One is a policy network,which is used to learn a resource allocation policy or a Lagrangian multiplier function.The other type of FNNs are hypernetworks,which are designed to learn the weight matrices and bias vectors of the policy network.Only the hypernetworks require training.Using the well-trained hypernetworks,the policy network is generated through forward propagation in the test phase.By introducing a simple data processing,the hypernetworks can well learn the weight matrices and bias vectors by inputting their indices,resulting in low training cost.Simulation results demonstrate that the learned bandwidth and power allocation policies by the PGNs perform very close to a numerical algorithm.Moreover,the PGNs can be well generalized to the number of users and wireless channels,and are with significantly lower memory costs,fewer training samples,and shorter training time than the traditional learning-based methods.
