As an important resource in data link,time slots should be strategically allocated to enhance transmission efficiency and resist eavesdropping,especially considering the tremendous increase in the number of nodes and ...As an important resource in data link,time slots should be strategically allocated to enhance transmission efficiency and resist eavesdropping,especially considering the tremendous increase in the number of nodes and diverse communication needs.It is crucial to design control sequences with robust randomness and conflict-freeness to properly address differentiated access control in data link.In this paper,we propose a hierarchical access control scheme based on control sequences to achieve high utilization of time slots and differentiated access control.A theoretical bound of the hierarchical control sequence set is derived to characterize the constraints on the parameters of the sequence set.Moreover,two classes of optimal hierarchical control sequence sets satisfying the theoretical bound are constructed,both of which enable the scheme to achieve maximum utilization of time slots.Compared with the fixed time slot allocation scheme,our scheme reduces the symbol error rate by up to 9%,which indicates a significant improvement in anti-interference and eavesdropping capabilities.展开更多
Sustainability and scalability remain critical hurdles for the commercialization of organic solar cells(OSCs).However,addressing both poses challenge.Herein,we introduce a simple yet effective strategy utilizing 3,5-d...Sustainability and scalability remain critical hurdles for the commercialization of organic solar cells(OSCs).However,addressing both poses challenge.Herein,we introduce a simple yet effective strategy utilizing 3,5-dichloropyridine(PDCC)as a solid additive to fine-tune the self-assembly behavior of Y-series non-fullerene acceptors(NFAs)to tackle the upscaling limitations in green-solvent-processed OSCs.PDCC predominantly interacts with Y-series NFAs,facilitating molecular crystallization and thereby driving the self-assembly of Y-series NFAs during film-forming dynamics,leading to more uniform active layers with improved molecular packing and reduced charge recombination.As a result,PDCC-driven self-assembly strategy enables high-performance OSCs with a power conversion efficiency(PCE)of 20.47%.When translated to sustainable fabrication,this strategy significantly boosts the PCE of large-area green-solvent-processed OSC modules(19.3 cm^(2))from 13.87%to 15.79%,ranking it among the best-performing green-solvent-processed large-area OSC modules(>18 cm^(2)).Beyond its impact on PCE enhancement,PDCC serves as a multifunctional additive to improve long-term stability and exhibits strong universality across multiple material systems.This work establishes a promising approach for advancing sustainable and scalable OSCs,paving the way for their commercialization.展开更多
AIM:To investigate the effects of binocular fusional C-optotypes(positive/negative)and 2D planar C-optotypes on the amplitude and stability of transient accommodation(TAC)in adults,and to provide a basis for non-conta...AIM:To investigate the effects of binocular fusional C-optotypes(positive/negative)and 2D planar C-optotypes on the amplitude and stability of transient accommodation(TAC)in adults,and to provide a basis for non-contact myopia intervention.METHODS:This was a self-controlled study.Using redblue 3D technology,four experimental stages were set up:Test A[fixating on the 1 m negative fusional C-optotypes,8△base-in(BI)],Test B(fixating on the 5 m planar C-optotypes),Test C(fixating on the 1 m planar C-optotypes),and Test D[fixating on the 1 m positive fusional C-optotypes,20△base-out(BO)].A WAM-5500 open-field autorefractor was used to measure TAC and accommodative microfluctuations[evaluated via interquartile range(IQR)and median-based coefficient of variation(CVmed)].Additionally,the convergence accommodation to convergence(CA/C)ratio was calculated,and a visual fatigue questionnaire was administered to assess participants’subjective visual comfort.RESULTS:A total of 21 subjects(7 males,14 females;aged 23-41y)with normal binocular visual function were enrolled.The results showed that the TAC increased gradually across the four stages,and these values were Test A(-0.35±0.26 D)<Test B(-0.46±0.24 D)<Test C(-0.77±0.32 D)<Test D(-1.38±0.31 D).There were significant overall differences(F=56.136,P<0.001).Compared with Test C,Test A reduced TAC by 0.42 D(P<0.05),while Test D increased it by 0.61 D(P<0.001).There was no significant intergroup difference in accommodative fluctuation amplitude(all P>0.05),but the fluctuation stability of Test D showed a significant difference between the first 20s and the second 20s(P=0.017).The CA/C ratio was significantly higher in Test D(0.05±0.02 D/△)than in Test A(0.03±0.02 D/△,P=0.007),indicating stronger accommodation-convergence linkage during positive fusional fixation.The visual fatigue scores of all stages were low(median 0-1),with Test D slightly higher than Test B and Test C(P<0.05).No linear correlation was found between TAC and age(all r<0.1,P>0.05).CONCLUSION:Negative fusional C-optotypes induce ciliary muscle relaxation to reduce TAC,while positive fusional C-optotypes enhance accommodation-convergence coordination to increase TAC.The red-blue 3D-based noncontact training mode exhibits good safety(median visual fatigue scores:0-1 across all tests)and provides a novel dual-directional(relaxation-activation)strategy for myopia prevention and control.展开更多
This paper proposes a fault-tolerant control scheme for Euler-Lagrange systems that ensures the tracking error decays to a pre-specified accuracy level within a prescribed time period,despite unknown actuation charact...This paper proposes a fault-tolerant control scheme for Euler-Lagrange systems that ensures the tracking error decays to a pre-specified accuracy level within a prescribed time period,despite unknown actuation characteristics and potential fading powering faults.By performing deliberately designed coordinate transformations on the tracking error,the complex and demanding problem of“reaching specified precision within a given time”is transformed into a bounded control problem,facilitating the development of the control scheme.To enhance practicality,the design incorporates smooth function fitting and dynamic surface control techniques.Additionally,the proposed control algorithm is robust to faults,effectively handling a combination of fading powering faults and additive actuator faults without requiring additional human intervention.Numerical simulations on a two-link robotic manipulator verify the effectiveness of the proposed control algorithm.展开更多
Background:Infectious disease control has historically functioned as a critical intersection of biological survival and social organization.For centuries,humanity relied on empirical defenses such as quarantine and en...Background:Infectious disease control has historically functioned as a critical intersection of biological survival and social organization.For centuries,humanity relied on empirical defenses such as quarantine and environmental sanitation.However,the theoretical foundation of prevention has shifted significantly toward biomedical sciences,including microbiology,immunology,and molecular biology.Methods:Using a public health history framework,this review synthesizes data from academic archives,monographs,and policy documents.We examined key case studies-Plague,Cholera,Influenza,HIV/AIDS,and COVID-19-to map the technological and institutional evolution of disease management.Results:We locate the primary historical turning point in the 19th century.It was here that control strategies evolved from crude population mandates into precise biomedical interventions.The synthesis of sanitary reform and germ theory catalyzed this era of scientific progress.Following the standardization of vaccines and antibiotics,the focus shifted to chronic management during the HIV/AIDS crisis.Contemporary tools like mRNA platforms and genomic surveillance continue this lineage,yet their practical application remains uneven globally.Conclusion:We conclude that biomedical breakthroughs are necessary but insufficient for security.Effective defense requires coupling scientific tools with resilient infrastructure and global health coordination to resolve systemic inequities.展开更多
Self-Centering Piston-Based Braced Frames(SC-PBBFs)are designed to curtail structural damage under severe ground motions.The self-centering mechanism in this bracing mitigates structural damage during an earthquake,th...Self-Centering Piston-Based Braced Frames(SC-PBBFs)are designed to curtail structural damage under severe ground motions.The self-centering mechanism in this bracing mitigates structural damage during an earthquake,thereby reducing post-earthquake repair costs and contributing to seismic resilience.However,non-structural components,particularly those sensitive to floor acceleration,remain vulnerable,resulting in prolonged func-tional recovery times.This paper aims to address this limitation by introducing a novel structural archetype,the Self-Centering Viscous-Based Braced Frame(SC-VBBF),which integrates superelastic shape memory alloy(SMA)bars,viscous dampers(VDs),and friction springs(FSs).A streamlined analytical approach relies on the strength decoupling of VD from other components using aλfactor to design SC-VBBFs.To evaluate the effectiveness of the hybrid brace,a set of 4-,8-,and 12-story archetypes equipped with SC-PBBs and SC-VBBFs are simulated in OpenSees and analyzed under various earthquake types,including crustal,subcrustal,and subduction events.The results demonstrate the superior performance of the SC-VBBF withλ≤0.5 system compared to SC-PBBFs in mitigating floor accelerations under design-level earthquakes and improving seismic resilience.展开更多
To enhance power flow regulation in scenarios involving large-scale renewable energy transmission via high-voltage direct current(HVDC)links and multi-infeed DC systems in load-center regions,this paper proposes a hyb...To enhance power flow regulation in scenarios involving large-scale renewable energy transmission via high-voltage direct current(HVDC)links and multi-infeed DC systems in load-center regions,this paper proposes a hybrid modular multilevel converter–capacitor-commutated line-commutated converter(MMC-CLCC)HVDC transmission system and its corresponding control strategy.First,the system topology is constructed,and a submodule configuration method for the MMC—combining full-bridge submodules(FBSMs)and half-bridge submodules(HBSMs)—is proposed to enable direct power flow reversal.Second,a hierarchical control strategy is introduced,includingMMCvoltage control,CLCC current control,and a coordinationmechanism,along with the derivation of the hybrid system’s power flow reversal characteristics.Third,leveraging the CLCC’s fast current regulation and theMMC’s negative voltage control capability,a coordinated power flow reversal control strategy is developed.Finally,an 800 kV MMC-CLCC hybrid HVDC system is modeled in PSCAD/EMTDC to validate the power flow reversal performance under a high proportion of full-bridge submodule configuration.Results demonstrate that the proposed control strategy enables rapid(1-s transition)and smooth switching of bidirectional power flow without modifying the structure of primary equipment:the transient fluctuation ofDC voltage from the rated value(UdcN)to themaximumreverse voltage(-kUdcN)is less than 5%;the DC current strictly follows the preset characteristic curve with a deviation of≤3%;the active power reverses continuously,and the system maintains stable operation throughout the reversal process.展开更多
The therapeutic efficacy of traditional Chinese medicine has been widely acknowledged due to its extensive history of clinical effectiveness.However,the precise active components underlying each prescription remain in...The therapeutic efficacy of traditional Chinese medicine has been widely acknowledged due to its extensive history of clinical effectiveness.However,the precise active components underlying each prescription remain incompletely understood.Polysaccharides,as a major constituent of water decoctions—the most common preparation method for Chinese medicinals—may provide a crucial avenue for deepening our understanding of the efficacy principles of Chinese medicine and establishing a framework for its modern development.The structural complexity and diversity of Chinese herbal polysaccharides present significant challenges in their separation and analysis compared to small molecules.This paper aims to explore the potential of Chinese herbal polysaccharides efficiently by briefly summarizing recent advancements in polysaccharide chemical research,focusing on methods of acquisition,structure elucidation,and quality control.展开更多
This paper is concerned with event-triggered control of discrete-time systems with or without input saturation.First,an accumulative-error-based event-triggered scheme is devised for control updates.When the accumulat...This paper is concerned with event-triggered control of discrete-time systems with or without input saturation.First,an accumulative-error-based event-triggered scheme is devised for control updates.When the accumulated error between the current state and the latest control update exceeds a certain threshold,an event is triggered.Such a scheme can ensure the event-generator works at a relatively low rate rather than falls into hibernation especially after the system steps into its steady state.Second,the looped functional method for continuous-time systems is extended to discrete-time systems.By introducing an innovative looped functional that links the event-triggered scheme,some sufficient conditions for the co-design of control gain and event-triggered parameters are obtained in terms of linear matrix inequalities with a couple of tuning parameters.Then,the proposed method is applied to discrete-time systems with input saturation.As a result,both suitable control gains and event-triggered parameters are also co-designed to ensure the system trajectories converge to the region of attraction.Finally,an unstable reactor system and an inverted pendulum system are given to show the effectiveness of the proposed method.展开更多
目的:探究血清CC趋化因子配体2(CCL2)、血管内皮生长因子(VEGFA)与非酒精性脂肪性肝病(NAFLD)患者肝纤维化和代谢综合征(MS)的关系。方法:选取2022年1月至2024年1月在本院就诊的NAFLD患者116例(NAFLD组)作为研究对象,根据患者否并发MS分...目的:探究血清CC趋化因子配体2(CCL2)、血管内皮生长因子(VEGFA)与非酒精性脂肪性肝病(NAFLD)患者肝纤维化和代谢综合征(MS)的关系。方法:选取2022年1月至2024年1月在本院就诊的NAFLD患者116例(NAFLD组)作为研究对象,根据患者否并发MS分为MS组(42例)和非MS组(74例),另取同期体检健康者66例作为对照组。收集所有受试者的临床资料;采用ELISA法检测血清中CCL2和VEGFA表达量;Pearson法分析血清CCL2、VEGFA水平与肝纤维化及MS相关指标的相关性;Logistic多因素分析影响NAFLD患者并发MS的因素;受试者工作特征曲线分析血清CCL2和VEGFA水平对NAFLD患者并发MS的预测价值。结果:NAFLD患者血清CCL2、VEGFA水平以及肝纤维化指标层黏连蛋白(LN)、透明质酸(HA)、Ⅲ型前胶原(PCⅢ)、Ⅳ型胶原(ⅣC)均显著高于对照组(P<0.05)。MS组的收缩压、舒张压、空腹血糖(FPG)、餐后2 h血糖(2 h PG)、甘油三椡(TG)、CCL2、VEGFA水平显著高于非MS组,丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)水平显著低于非MS组(P<0.05)。血清中CCL2和VEGFA水平与LN、HA、PCⅢ、ⅣC、收缩压、舒张压、FPG、2 h PG、TG呈正相关,与ALT、AST呈负相关(P<0.05)。收缩压、舒张压、FPG、2 h PG、TG、CCL2、VEGFA是影响NAFLD患者并发MS的危险因素,ALT、AST是影响NAFLD患者并发MS的保护因素(P<0.05)。血清CCL2和VEGFA水平以及联合预测NAFLD患者并发MS情况的曲线下面积分别为0.842、0.884和0.938,联合预测优于各自单独预测(Z_(联合-CCL2)=2.959、Z_(联合-VEGFA)=2.731,P=0.003、0.006)。结论:NAFLD患者血清CCL2和VEGFA水平升高,且二者与NAFLD患者肝纤维化和MS密切相关,二者联合对NAFLD患者并发MS具有较高的预测价值。展开更多
Renewable Energy Systems(RES)provide a sustainable solution to climate warming and environmental pollution by enhancing stability and reliability through status acquisition and analysis on cloud platforms and intellig...Renewable Energy Systems(RES)provide a sustainable solution to climate warming and environmental pollution by enhancing stability and reliability through status acquisition and analysis on cloud platforms and intelligent processing on edge servers(ES).However,securely distributing encrypted data stored in the cloud to terminals that meet decryption requirements has become a prominent research topic.Additionally,managing attributes,including addition,deletion,and modification,is a crucial issue in the access control scheme for RES.To address these security concerns,a trust-based ciphertext-policy attribute-based encryption(CP-ABE)device access control scheme is proposed for RES(TB-CP-ABE).This scheme effectivelymanages the distribution and control of encrypted data on the cloud through robust attribute key management.By introducing trust management mechanisms and outsourced decryption technology,the ES system can effectively assess and manage the trust worthiness of terminal devices,ensuring that only trusted devices can participate in data exchange and access sensitive information.Besides,the ES system dynamically evaluates trust scores to set decryption trust thresholds,thereby regulating device data access permissions and enhancing the system’s security.To validate the security of the proposed TB-CP-ABE against chosen plaintext attacks,a comprehensive formal security analysis is conducted using the widely accepted random oraclemodel under the decisional q-Bilinear Diffie-Hellman Exponent(q-BDHE)assumption.Finally,comparative analysis with other schemes demonstrates that the TB-CP-ABE scheme cuts energy/communication costs by 43%,and scaleswell with rising terminals,maintaining average latency below 50ms,ensuring real-time service feasibility.The proposed scheme not only provides newinsights for the secure management of RES but also lays a foundation for future secure energy solutions.展开更多
This paper solves the problem of model-free dual-arm space robot maneuvering after non-cooperative target capture under high control quality requirements.The explicit system model is unavailable,and the maneuvering mi...This paper solves the problem of model-free dual-arm space robot maneuvering after non-cooperative target capture under high control quality requirements.The explicit system model is unavailable,and the maneuvering mission is disturbed by the measurement noise and the target adversarial behavior.To address these problems,a model-free Combined Adaptive-length Datadriven Predictive Controller(CADPC)is proposed.It consists of a separated subsystem identification method and a combined predictive control strategy.The subsystem identification method is composed of an adaptive data length,thereby reducing sensitivity to undetermined measurement noises and disturbances.Based on the subsystem identification,the combined predictive controller is established,reducing calculating resource.The stability of the CADPC is rigorously proven using the Input-to-State Stable(ISS)theorem and the small-gain theorem.Simulations demonstrate that CADPC effectively handles the model-free space robot post operation in the presence of significant disturbances,state measurement noise,and control input errors.It achieves improved steady-state accuracy,reduced steady-state control consumption,and minimized control input chattering.展开更多
CO_(2)-responsive gels,which swell upon contact with CO_(2),are widely used for profile control to plug high-permeability gas flow channels in carbon capture,utilization,and storage(CCUS)applications in oil reser-voir...CO_(2)-responsive gels,which swell upon contact with CO_(2),are widely used for profile control to plug high-permeability gas flow channels in carbon capture,utilization,and storage(CCUS)applications in oil reser-voirs.However,the use of these gels in high-temperature CCUS applications is limited due to their rever-sible swelling behavior at elevated temperatures.In this study,a novel dispersed particle gel(DPG)suspension is developed for high-temperature profile control in CCUS applications.First,we synthesize a double-network hydrogel consisting of a crosslinked polyacrylamide(PAAm)network and a crosslinked sodium alginate(SA)network.The hydrogel is then sheared in water to form a pre-prepared DPG suspen-sion.To enhance its performance,the gel particles are modified by introducing potassium methylsilan-etriolate(PMS)upon CO_(2) exposure.Comparing the particle size distributions of the modified and pre-prepared DPG suspension reveals a significant swelling of gel particles,over twice their original size.Moreover,subjecting the new DPG suspension to a 100℃ environment for 24 h demonstrates that its gel particle sizes do not decrease,confirming irreversible swelling,which is a significant advantage over the traditional CO_(2)-responsive gels.Thermogravimetric analysis further indicates improved thermal sta-bility compared to the pre-prepared DPG particles.Core flooding experiments show that the new DPG suspension achieves a high plugging efficiency of 95.3%in plugging an ultra-high permeability sandpack,whereas the pre-prepared DPG suspension achieves only 82.8%.With its high swelling ratio,irreversible swelling at high temperatures,enhanced thermal stability,and superior plugging performance,the newly developed DPG suspension in this work presents a highly promising solution for profile control in high-temperature CCUS applications.展开更多
This paper presents and describes an approach to generate innovative labeled datasets that enable automated text classifiers to automatically detect online employee reviews referring to accounting control deficiencies...This paper presents and describes an approach to generate innovative labeled datasets that enable automated text classifiers to automatically detect online employee reviews referring to accounting control deficiencies,facili-tating supplementary monitoring for auditors and management.Employees,who are on the front lines executing policies and procedures,play a critical role in a firm's control environment.Their feedback provides insights into how controls are functioning.Textual data were collected and manually coded using a structured coding scheme mapped to COSO internal control framework(2013)principles.The dataset is unique in that it provides a new source of data that has not been previously used in internal control research,offering new opportunities for exploring the relationship between employee feedback and control weaknesses,and shedding light on potential improvements in internal control practices.Downstream stakeholders(such as researchers,management,in-vestors,and auditors)can benefit by having rapid,automated means for filtering and prioritizing employee reviews for further investigation,with respect to accounting control issue mentions.展开更多
基金supported by the National Science Foundation of China(No.62171387)the Science and Technology Program of Sichuan Province(No.2024NSFSC0468)the China Postdoctoral Science Foundation(No.2019M663475).
文摘As an important resource in data link,time slots should be strategically allocated to enhance transmission efficiency and resist eavesdropping,especially considering the tremendous increase in the number of nodes and diverse communication needs.It is crucial to design control sequences with robust randomness and conflict-freeness to properly address differentiated access control in data link.In this paper,we propose a hierarchical access control scheme based on control sequences to achieve high utilization of time slots and differentiated access control.A theoretical bound of the hierarchical control sequence set is derived to characterize the constraints on the parameters of the sequence set.Moreover,two classes of optimal hierarchical control sequence sets satisfying the theoretical bound are constructed,both of which enable the scheme to achieve maximum utilization of time slots.Compared with the fixed time slot allocation scheme,our scheme reduces the symbol error rate by up to 9%,which indicates a significant improvement in anti-interference and eavesdropping capabilities.
基金the research grant from the Youth Fund of the National Natural Science Foundation of China(62305340)the financial support from the Hong Kong Research Grant Council via STEM Postdoctoral Fellowship(Project no.9446002)+6 种基金the Alexander von Humboldt Foundation and the support during his stay in Christoph J.Brabec’s group at Friedrich-Alexander-Universität Erlangen-Nürnberg and Helmholtz-Institute Erlangen-Nürnberg(HI ERN)the research grant from KAUST global fellowship postdocfinancial support from the Innovation and Technology Commission(Grant no.MHP/104/21)Shenzhen Science and Technology Innovation Commission(JCYJ20210324125612035,R-IND12303,and R-IND12304)the National Key Research and Development Program of China(no.2021YFA1500900)the National Natural Science Foundation of China(no.52071174)the support from the Hong Kong Jockey Club under the research work Hong Kong JC STEM Lab for Circular Bio-economy(Project No.2023-0078)。
文摘Sustainability and scalability remain critical hurdles for the commercialization of organic solar cells(OSCs).However,addressing both poses challenge.Herein,we introduce a simple yet effective strategy utilizing 3,5-dichloropyridine(PDCC)as a solid additive to fine-tune the self-assembly behavior of Y-series non-fullerene acceptors(NFAs)to tackle the upscaling limitations in green-solvent-processed OSCs.PDCC predominantly interacts with Y-series NFAs,facilitating molecular crystallization and thereby driving the self-assembly of Y-series NFAs during film-forming dynamics,leading to more uniform active layers with improved molecular packing and reduced charge recombination.As a result,PDCC-driven self-assembly strategy enables high-performance OSCs with a power conversion efficiency(PCE)of 20.47%.When translated to sustainable fabrication,this strategy significantly boosts the PCE of large-area green-solvent-processed OSC modules(19.3 cm^(2))from 13.87%to 15.79%,ranking it among the best-performing green-solvent-processed large-area OSC modules(>18 cm^(2)).Beyond its impact on PCE enhancement,PDCC serves as a multifunctional additive to improve long-term stability and exhibits strong universality across multiple material systems.This work establishes a promising approach for advancing sustainable and scalable OSCs,paving the way for their commercialization.
文摘AIM:To investigate the effects of binocular fusional C-optotypes(positive/negative)and 2D planar C-optotypes on the amplitude and stability of transient accommodation(TAC)in adults,and to provide a basis for non-contact myopia intervention.METHODS:This was a self-controlled study.Using redblue 3D technology,four experimental stages were set up:Test A[fixating on the 1 m negative fusional C-optotypes,8△base-in(BI)],Test B(fixating on the 5 m planar C-optotypes),Test C(fixating on the 1 m planar C-optotypes),and Test D[fixating on the 1 m positive fusional C-optotypes,20△base-out(BO)].A WAM-5500 open-field autorefractor was used to measure TAC and accommodative microfluctuations[evaluated via interquartile range(IQR)and median-based coefficient of variation(CVmed)].Additionally,the convergence accommodation to convergence(CA/C)ratio was calculated,and a visual fatigue questionnaire was administered to assess participants’subjective visual comfort.RESULTS:A total of 21 subjects(7 males,14 females;aged 23-41y)with normal binocular visual function were enrolled.The results showed that the TAC increased gradually across the four stages,and these values were Test A(-0.35±0.26 D)<Test B(-0.46±0.24 D)<Test C(-0.77±0.32 D)<Test D(-1.38±0.31 D).There were significant overall differences(F=56.136,P<0.001).Compared with Test C,Test A reduced TAC by 0.42 D(P<0.05),while Test D increased it by 0.61 D(P<0.001).There was no significant intergroup difference in accommodative fluctuation amplitude(all P>0.05),but the fluctuation stability of Test D showed a significant difference between the first 20s and the second 20s(P=0.017).The CA/C ratio was significantly higher in Test D(0.05±0.02 D/△)than in Test A(0.03±0.02 D/△,P=0.007),indicating stronger accommodation-convergence linkage during positive fusional fixation.The visual fatigue scores of all stages were low(median 0-1),with Test D slightly higher than Test B and Test C(P<0.05).No linear correlation was found between TAC and age(all r<0.1,P>0.05).CONCLUSION:Negative fusional C-optotypes induce ciliary muscle relaxation to reduce TAC,while positive fusional C-optotypes enhance accommodation-convergence coordination to increase TAC.The red-blue 3D-based noncontact training mode exhibits good safety(median visual fatigue scores:0-1 across all tests)and provides a novel dual-directional(relaxation-activation)strategy for myopia prevention and control.
基金supported in part by the National Natural Science Foundation of China(W2411061,624B2029)the Graduate Research and Innovation Foundation of Chongqing,China(CYS20069)+1 种基金the Fundamental Research Funds for the Central Universities(2024CDJYXTD-007)the Natural Science Foundation of Chongqing(CSTB2023NSCQ-LZX0026).
文摘This paper proposes a fault-tolerant control scheme for Euler-Lagrange systems that ensures the tracking error decays to a pre-specified accuracy level within a prescribed time period,despite unknown actuation characteristics and potential fading powering faults.By performing deliberately designed coordinate transformations on the tracking error,the complex and demanding problem of“reaching specified precision within a given time”is transformed into a bounded control problem,facilitating the development of the control scheme.To enhance practicality,the design incorporates smooth function fitting and dynamic surface control techniques.Additionally,the proposed control algorithm is robust to faults,effectively handling a combination of fading powering faults and additive actuator faults without requiring additional human intervention.Numerical simulations on a two-link robotic manipulator verify the effectiveness of the proposed control algorithm.
基金supported by the National Key Research and Development Program(Grant No.2024YFA0917200)the Projects of the Chinese Center for Disease Control and Prevention(Grant No.BB2110240090)World Medical History under the Education Innovation Plan of the University of Science and Technology of China(Grant No.2024YCHX07).
文摘Background:Infectious disease control has historically functioned as a critical intersection of biological survival and social organization.For centuries,humanity relied on empirical defenses such as quarantine and environmental sanitation.However,the theoretical foundation of prevention has shifted significantly toward biomedical sciences,including microbiology,immunology,and molecular biology.Methods:Using a public health history framework,this review synthesizes data from academic archives,monographs,and policy documents.We examined key case studies-Plague,Cholera,Influenza,HIV/AIDS,and COVID-19-to map the technological and institutional evolution of disease management.Results:We locate the primary historical turning point in the 19th century.It was here that control strategies evolved from crude population mandates into precise biomedical interventions.The synthesis of sanitary reform and germ theory catalyzed this era of scientific progress.Following the standardization of vaccines and antibiotics,the focus shifted to chronic management during the HIV/AIDS crisis.Contemporary tools like mRNA platforms and genomic surveillance continue this lineage,yet their practical application remains uneven globally.Conclusion:We conclude that biomedical breakthroughs are necessary but insufficient for security.Effective defense requires coupling scientific tools with resilient infrastructure and global health coordination to resolve systemic inequities.
文摘Self-Centering Piston-Based Braced Frames(SC-PBBFs)are designed to curtail structural damage under severe ground motions.The self-centering mechanism in this bracing mitigates structural damage during an earthquake,thereby reducing post-earthquake repair costs and contributing to seismic resilience.However,non-structural components,particularly those sensitive to floor acceleration,remain vulnerable,resulting in prolonged func-tional recovery times.This paper aims to address this limitation by introducing a novel structural archetype,the Self-Centering Viscous-Based Braced Frame(SC-VBBF),which integrates superelastic shape memory alloy(SMA)bars,viscous dampers(VDs),and friction springs(FSs).A streamlined analytical approach relies on the strength decoupling of VD from other components using aλfactor to design SC-VBBFs.To evaluate the effectiveness of the hybrid brace,a set of 4-,8-,and 12-story archetypes equipped with SC-PBBs and SC-VBBFs are simulated in OpenSees and analyzed under various earthquake types,including crustal,subcrustal,and subduction events.The results demonstrate the superior performance of the SC-VBBF withλ≤0.5 system compared to SC-PBBFs in mitigating floor accelerations under design-level earthquakes and improving seismic resilience.
基金supported by Science and Technology Project of the headquarters of the State Grid Corporation of China(No.5500-202324492A-3-2-ZN).
文摘To enhance power flow regulation in scenarios involving large-scale renewable energy transmission via high-voltage direct current(HVDC)links and multi-infeed DC systems in load-center regions,this paper proposes a hybrid modular multilevel converter–capacitor-commutated line-commutated converter(MMC-CLCC)HVDC transmission system and its corresponding control strategy.First,the system topology is constructed,and a submodule configuration method for the MMC—combining full-bridge submodules(FBSMs)and half-bridge submodules(HBSMs)—is proposed to enable direct power flow reversal.Second,a hierarchical control strategy is introduced,includingMMCvoltage control,CLCC current control,and a coordinationmechanism,along with the derivation of the hybrid system’s power flow reversal characteristics.Third,leveraging the CLCC’s fast current regulation and theMMC’s negative voltage control capability,a coordinated power flow reversal control strategy is developed.Finally,an 800 kV MMC-CLCC hybrid HVDC system is modeled in PSCAD/EMTDC to validate the power flow reversal performance under a high proportion of full-bridge submodule configuration.Results demonstrate that the proposed control strategy enables rapid(1-s transition)and smooth switching of bidirectional power flow without modifying the structure of primary equipment:the transient fluctuation ofDC voltage from the rated value(UdcN)to themaximumreverse voltage(-kUdcN)is less than 5%;the DC current strictly follows the preset characteristic curve with a deviation of≤3%;the active power reverses continuously,and the system maintains stable operation throughout the reversal process.
基金supported by the Science and Technology Development Fund,Macao SAR (Nos.0075/2022/A and028/2022/ITP)the Zhuhai Science and Technology Plan Project in the Social Development Field (No.2220004000117)the University of Macao (Nos.MYRG-GRG2023-00082-ICMS-UMDF/CPG2024-00011-ICMS)。
文摘The therapeutic efficacy of traditional Chinese medicine has been widely acknowledged due to its extensive history of clinical effectiveness.However,the precise active components underlying each prescription remain incompletely understood.Polysaccharides,as a major constituent of water decoctions—the most common preparation method for Chinese medicinals—may provide a crucial avenue for deepening our understanding of the efficacy principles of Chinese medicine and establishing a framework for its modern development.The structural complexity and diversity of Chinese herbal polysaccharides present significant challenges in their separation and analysis compared to small molecules.This paper aims to explore the potential of Chinese herbal polysaccharides efficiently by briefly summarizing recent advancements in polysaccharide chemical research,focusing on methods of acquisition,structure elucidation,and quality control.
基金supported in part by the National Natural Science Foundation of China(62473221)the Natural Science Foundation of Shandong Province,China(ZR2024MF006)Qingdao Natural Science Foundation(24-4-4-zrjj-165-jch)。
文摘This paper is concerned with event-triggered control of discrete-time systems with or without input saturation.First,an accumulative-error-based event-triggered scheme is devised for control updates.When the accumulated error between the current state and the latest control update exceeds a certain threshold,an event is triggered.Such a scheme can ensure the event-generator works at a relatively low rate rather than falls into hibernation especially after the system steps into its steady state.Second,the looped functional method for continuous-time systems is extended to discrete-time systems.By introducing an innovative looped functional that links the event-triggered scheme,some sufficient conditions for the co-design of control gain and event-triggered parameters are obtained in terms of linear matrix inequalities with a couple of tuning parameters.Then,the proposed method is applied to discrete-time systems with input saturation.As a result,both suitable control gains and event-triggered parameters are also co-designed to ensure the system trajectories converge to the region of attraction.Finally,an unstable reactor system and an inverted pendulum system are given to show the effectiveness of the proposed method.
文摘目的:探究血清CC趋化因子配体2(CCL2)、血管内皮生长因子(VEGFA)与非酒精性脂肪性肝病(NAFLD)患者肝纤维化和代谢综合征(MS)的关系。方法:选取2022年1月至2024年1月在本院就诊的NAFLD患者116例(NAFLD组)作为研究对象,根据患者否并发MS分为MS组(42例)和非MS组(74例),另取同期体检健康者66例作为对照组。收集所有受试者的临床资料;采用ELISA法检测血清中CCL2和VEGFA表达量;Pearson法分析血清CCL2、VEGFA水平与肝纤维化及MS相关指标的相关性;Logistic多因素分析影响NAFLD患者并发MS的因素;受试者工作特征曲线分析血清CCL2和VEGFA水平对NAFLD患者并发MS的预测价值。结果:NAFLD患者血清CCL2、VEGFA水平以及肝纤维化指标层黏连蛋白(LN)、透明质酸(HA)、Ⅲ型前胶原(PCⅢ)、Ⅳ型胶原(ⅣC)均显著高于对照组(P<0.05)。MS组的收缩压、舒张压、空腹血糖(FPG)、餐后2 h血糖(2 h PG)、甘油三椡(TG)、CCL2、VEGFA水平显著高于非MS组,丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)水平显著低于非MS组(P<0.05)。血清中CCL2和VEGFA水平与LN、HA、PCⅢ、ⅣC、收缩压、舒张压、FPG、2 h PG、TG呈正相关,与ALT、AST呈负相关(P<0.05)。收缩压、舒张压、FPG、2 h PG、TG、CCL2、VEGFA是影响NAFLD患者并发MS的危险因素,ALT、AST是影响NAFLD患者并发MS的保护因素(P<0.05)。血清CCL2和VEGFA水平以及联合预测NAFLD患者并发MS情况的曲线下面积分别为0.842、0.884和0.938,联合预测优于各自单独预测(Z_(联合-CCL2)=2.959、Z_(联合-VEGFA)=2.731,P=0.003、0.006)。结论:NAFLD患者血清CCL2和VEGFA水平升高,且二者与NAFLD患者肝纤维化和MS密切相关,二者联合对NAFLD患者并发MS具有较高的预测价值。
基金supported by the Science and Technology Project of the State Grid Corporation of China,Grant number 5700-202223189A-1-1-ZN.
文摘Renewable Energy Systems(RES)provide a sustainable solution to climate warming and environmental pollution by enhancing stability and reliability through status acquisition and analysis on cloud platforms and intelligent processing on edge servers(ES).However,securely distributing encrypted data stored in the cloud to terminals that meet decryption requirements has become a prominent research topic.Additionally,managing attributes,including addition,deletion,and modification,is a crucial issue in the access control scheme for RES.To address these security concerns,a trust-based ciphertext-policy attribute-based encryption(CP-ABE)device access control scheme is proposed for RES(TB-CP-ABE).This scheme effectivelymanages the distribution and control of encrypted data on the cloud through robust attribute key management.By introducing trust management mechanisms and outsourced decryption technology,the ES system can effectively assess and manage the trust worthiness of terminal devices,ensuring that only trusted devices can participate in data exchange and access sensitive information.Besides,the ES system dynamically evaluates trust scores to set decryption trust thresholds,thereby regulating device data access permissions and enhancing the system’s security.To validate the security of the proposed TB-CP-ABE against chosen plaintext attacks,a comprehensive formal security analysis is conducted using the widely accepted random oraclemodel under the decisional q-Bilinear Diffie-Hellman Exponent(q-BDHE)assumption.Finally,comparative analysis with other schemes demonstrates that the TB-CP-ABE scheme cuts energy/communication costs by 43%,and scaleswell with rising terminals,maintaining average latency below 50ms,ensuring real-time service feasibility.The proposed scheme not only provides newinsights for the secure management of RES but also lays a foundation for future secure energy solutions.
基金supported by the National Natural Science Foundation of China(No.12372045)the National Key Research and the Development Program of China(Nos.2023YFC2205900,2023YFC2205901)。
文摘This paper solves the problem of model-free dual-arm space robot maneuvering after non-cooperative target capture under high control quality requirements.The explicit system model is unavailable,and the maneuvering mission is disturbed by the measurement noise and the target adversarial behavior.To address these problems,a model-free Combined Adaptive-length Datadriven Predictive Controller(CADPC)is proposed.It consists of a separated subsystem identification method and a combined predictive control strategy.The subsystem identification method is composed of an adaptive data length,thereby reducing sensitivity to undetermined measurement noises and disturbances.Based on the subsystem identification,the combined predictive controller is established,reducing calculating resource.The stability of the CADPC is rigorously proven using the Input-to-State Stable(ISS)theorem and the small-gain theorem.Simulations demonstrate that CADPC effectively handles the model-free space robot post operation in the presence of significant disturbances,state measurement noise,and control input errors.It achieves improved steady-state accuracy,reduced steady-state control consumption,and minimized control input chattering.
基金Lin Du acknowledges the financial support provided by China Scholarship Council(CSC)via a Ph.D.Scholarship(202008510128)supported by Core Technology Project of China National Petroleum Corporation(CNPC)"Research on Thermal Miscible Flooding Technology"(2023ZG18)。
文摘CO_(2)-responsive gels,which swell upon contact with CO_(2),are widely used for profile control to plug high-permeability gas flow channels in carbon capture,utilization,and storage(CCUS)applications in oil reser-voirs.However,the use of these gels in high-temperature CCUS applications is limited due to their rever-sible swelling behavior at elevated temperatures.In this study,a novel dispersed particle gel(DPG)suspension is developed for high-temperature profile control in CCUS applications.First,we synthesize a double-network hydrogel consisting of a crosslinked polyacrylamide(PAAm)network and a crosslinked sodium alginate(SA)network.The hydrogel is then sheared in water to form a pre-prepared DPG suspen-sion.To enhance its performance,the gel particles are modified by introducing potassium methylsilan-etriolate(PMS)upon CO_(2) exposure.Comparing the particle size distributions of the modified and pre-prepared DPG suspension reveals a significant swelling of gel particles,over twice their original size.Moreover,subjecting the new DPG suspension to a 100℃ environment for 24 h demonstrates that its gel particle sizes do not decrease,confirming irreversible swelling,which is a significant advantage over the traditional CO_(2)-responsive gels.Thermogravimetric analysis further indicates improved thermal sta-bility compared to the pre-prepared DPG particles.Core flooding experiments show that the new DPG suspension achieves a high plugging efficiency of 95.3%in plugging an ultra-high permeability sandpack,whereas the pre-prepared DPG suspension achieves only 82.8%.With its high swelling ratio,irreversible swelling at high temperatures,enhanced thermal stability,and superior plugging performance,the newly developed DPG suspension in this work presents a highly promising solution for profile control in high-temperature CCUS applications.
文摘This paper presents and describes an approach to generate innovative labeled datasets that enable automated text classifiers to automatically detect online employee reviews referring to accounting control deficiencies,facili-tating supplementary monitoring for auditors and management.Employees,who are on the front lines executing policies and procedures,play a critical role in a firm's control environment.Their feedback provides insights into how controls are functioning.Textual data were collected and manually coded using a structured coding scheme mapped to COSO internal control framework(2013)principles.The dataset is unique in that it provides a new source of data that has not been previously used in internal control research,offering new opportunities for exploring the relationship between employee feedback and control weaknesses,and shedding light on potential improvements in internal control practices.Downstream stakeholders(such as researchers,management,in-vestors,and auditors)can benefit by having rapid,automated means for filtering and prioritizing employee reviews for further investigation,with respect to accounting control issue mentions.
