In this study,an integrated thermal protection system was formed by bonding the Carbon/Carbon(C/C) composite thermal insulation layer and carbon foam thermal insulation tile on an aluminum honeycomb sandwich panel acc...In this study,an integrated thermal protection system was formed by bonding the Carbon/Carbon(C/C) composite thermal insulation layer and carbon foam thermal insulation tile on an aluminum honeycomb sandwich panel according to the functions of each layer of materials,and the thermal–mechanical response was analyzed by experimental tests and numerical simulations.First,infrared lamp facility and arcjet wind tunnel tests were used to check the accuracy of the model and calculate the heat-shielding index.Then,using the aerodynamic heat flow and pressure of the vehicles re-entry process,the temperature field and thermal deformation of the thermal protection system were analyzed according to the thermal–mechanical coupling analysis,and its performance requirements as a vehicles shell were evaluated.Analysis show that the thermomechanical properties of each layer were mismatched due to thermal deformation,resulting in debonding at the interlayer interface,which was also observed in the experiment.In addition,a 1 mm gap in the insulation tile promotes the release of thermal stress and reduces interlayer disbonding.According to the multi-scale model,10 thermal cycles(corresponding to the flight process) were analyzed,and the failure and damage evolution process of C/C composites at the microscopic level were revealed.The results of thermal cycling show that the microscopic damage started from the interfacial debonding of the fiber/matrix and ended with the connection of the pores through crack propagation in the matrix.This study provides a solution for analyzing the thermal–mechanical response of a thermal protection system and a design solution for improving reusability.展开更多
Power system protection has evolved significantly due to the ongoing energy transition and digitalization.The development and standardization of information and communication technologies(ICTs)used for power system pr...Power system protection has evolved significantly due to the ongoing energy transition and digitalization.The development and standardization of information and communication technologies(ICTs)used for power system protection,monitoring,and control have led to the digitalization of substations and the introduction of new protection and control schemes.These include virtualized centralized protection and control for in-tra-substation applications,as well as advanced wide-area monitoring,protection,and control(WAMPAC)for inter-substation applications.This paper reviews the development of virtualized centralized protection,with a focus on key practical advancements,emerging technolo-gies,and state-of-the-art studies in centralized protection and control(CPC)and WAMPAC systems.It also identifies directions for future research.展开更多
Objective To study the drug test data protection system in foreign countries,and to foster pharmaceutical innovation and increase drug accessibility in China.Methods The development history of drug test data protectio...Objective To study the drug test data protection system in foreign countries,and to foster pharmaceutical innovation and increase drug accessibility in China.Methods The development history of drug test data protection was analyzed to examine and evaluate China’s current drug test data protection system so as to offer recommendations for its improvement.Finally,the drug test data protection system in China can be officially implemented.Results and Conclusion The drug test data protection system aims to promote innovation by protecting the trial data of innovative drugs.In a broad sense,this belongs to intellectual property protection,but it is different from patent protection.Although China has established a drug testing data protection system after joining the“Agreement on Trade-Related Aspects of Intellectual Property Rights(TRIPS)”,the relevant provisions and regulations have not yet been formally formed,and the system has not yet been implemented.Therefore,some suggestions for improving China’s drug testing data protection system are proposed to achieve good social benefits.展开更多
Hypervelocity rocket sled systems are critical for testing advanced military technologies,yet track damage at speeds exceeding Mach 5 remains a significant challenge for system reliability and performance.In this stud...Hypervelocity rocket sled systems are critical for testing advanced military technologies,yet track damage at speeds exceeding Mach 5 remains a significant challenge for system reliability and performance.In this study,we investigated the hypervelocity impact response and protection for highstrength U71 Mn or bainitic steel used in rocket sled tracks.Flyer plate impact experiments using a two-stage light-gas gun were conducted to study the hypervelocity collision response,followed by the microstructural characterization via optical microscope,scanning electron microscopy equipped with electron backscatter diffraction to reveal underlying damage mechanisms.Then,the calibrated thermalmechanical coupled finite element simulations using the Johnson-Cook constitutive model and MieGrüneisen equation of state were carried out.Results indicated that bainitic steel exhibits superior impact resistance with predominantly smooth scratch-dominated damage due to its higher ductility.In contrast,U71 Mn suffered significant material spallation and crack propagation arising from brittle fracture mechanisms.Zinc-rich epoxy primer coatings effectively mitigated stress concentration and temperature rise in the substrate at impacting velocities below 2.4 km/s,so as to suppress the microstructural damage such as adiabatic shear bands and dynamic recrystallization.However,coating protection diminished at ultra-high-speed impacts due to the coating failure.Dimensional analysis established quantitative relationships of the gouge damage size to projectile mass,impact velocity,and material yield strength.This study provides in-depth insights into damage mechanisms in hypervelocity rail systems,demonstrating that bainitic steel combined with protective coatings can significantly enhance impact resistance and system reliability,offering valuable guidance for the design and optimization of hypervelocity testing platforms.展开更多
The regenerative braking energy utilization system(RBEUS)stands as a promising technique for improving the efficiency and power quality of electrified railways.Beyond the vital aspects of energy management and control...The regenerative braking energy utilization system(RBEUS)stands as a promising technique for improving the efficiency and power quality of electrified railways.Beyond the vital aspects of energy management and control strategies,ensuring fault protection is paramount for the secure and steady operation of the traction power supply system(TPSS)integrated with RBEUS.This paper introduces an innovative protection scheme tailored to diverse RBEUS application scenarios.Firstly,fault categories are streamlined into three levels:system,equipment,and warning.Subsequently,a novel multi-port active power differential protection method,aligned with RBEUS operational principles,is crafted to serve as a comprehensive and sensitive main protection.Building upon this foundation,a hierarchical protection structure for RBEUS is established,addressing the intricacies and variations in fault types while boosting anti-disturbance capabilities under faulty conditions.Embracing the principle of railway-oriented safety,a collaborative RBEUS-TPSS protection scheme is put forth.Finally,through simulated scenarios encompassing various fault conditions,the proposed scheme’s feasibility and effectiveness are convincingly validated.展开更多
With the increasing demand for secure infrastructure such as hydrogen refueling stations,chemical plants,and energy storage systems,the need for protective structures capable of withstanding close-in detonations has b...With the increasing demand for secure infrastructure such as hydrogen refueling stations,chemical plants,and energy storage systems,the need for protective structures capable of withstanding close-in detonations has become more critical.Existing design guidelines for protective walls(e.g.,UFC 3-340-02)primarily address mid-and far-field explosions,providing limited insights into near-field effects.Considering the effect of slight slopes(<40°)on reducing maximum reflected overpressure is deemed negligible.This study investigated the effectiveness of a reinforced concrete(RC)modular protection system(MPS)incorpo rating a diagonally tapered wall in attenuating re flected overpressures from closein detonations.Full-scale field experiments using a 51.3 kg TNT charge,representing the explosion energy of a typical hydrogen vessel rupture,demonstrated that a wall with a 7°slope significantly outperformed a vertical wall of equivalent concrete volume in terms of blast resistance.Observed structural responses included cracking,horizontal shear failure,and overturning.Complementary simulations using a validated computational fluid dynamics(CFD)model showed that the tapered wall reduced peak overpressure by 30%-40%compared to an equivalent vertical wall.This result highlights the potential of minor geometric modifications to enhance blast resilience.The tapered design effectively redirects incident blast waves,reducing localized damage while also conserving material,thus preserving modular benefits such as ease of transport and reusability.These findings suggest that diagonally tapered RC-based MPSs can offer a practical and resilient solution for industrial and military applications subject to near-field or sequential blast threats.展开更多
This article takes the current autonomous driving technology as the research background and studies the collaborative protection mechanism between its system-on-chip(SoC)functional safety and information security.It i...This article takes the current autonomous driving technology as the research background and studies the collaborative protection mechanism between its system-on-chip(SoC)functional safety and information security.It includes an introduction to the functions and information security of autonomous driving SoCs,as well as the main design strategies for the collaborative prevention and control mechanism of SoC functional safety and information security in autonomous driving.The research shows that in the field of autonomous driving,there is a close connection between the functional safety of SoCs and their information security.In the design of the safety collaborative protection mechanism,the overall collaborative protection architecture,SoC functional safety protection mechanism,information security protection mechanism,the workflow of the collaborative protection mechanism,and its strategies are all key design elements.It is hoped that this analysis can provide some references for the collaborative protection of SoC functional safety and information security in the field of autonomous driving,so as to improve the safety of autonomous driving technology and meet its practical application requirements.展开更多
1.Introduction to ablative TPS The Mars 2020 mission underscored the critical role of ablative Thermal Protection Systems(TPS)during atmospheric entry,where spacecraft encounter extreme aerodynamic heating.Established...1.Introduction to ablative TPS The Mars 2020 mission underscored the critical role of ablative Thermal Protection Systems(TPS)during atmospheric entry,where spacecraft encounter extreme aerodynamic heating.Established in the mid-20th century,blunt body theories led to the creation of ablative heat shields that effectively manage thermal loads through thermo-chemo-mechanical decomposition.This paper revisits the development and application of ablative TPS materials,which are single-mission solutions capable of withstanding entry velocities surpassing 10 km/s.展开更多
The protection system for traditional Chinese medicine(TCM)varieties,as an important policy tool to promote the development of TCM,has a long history of over 30 years,from the promulgation of the“Regulations on the P...The protection system for traditional Chinese medicine(TCM)varieties,as an important policy tool to promote the development of TCM,has a long history of over 30 years,from the promulgation of the“Regulations on the Protection of Traditional Chinese Medicine Varieties”in 1992 to the comprehensive revision of the draft for soliciting opinions in 2022.The TCM protection system evolves to meet the needs of innovative development of TCM.This paper reviews the policy developments in TCM varieties protection,collates protection data(1993 to 2024),and analyzes enterprises application strategies amid impending regulatory changes.展开更多
Avian metapneumovirus(aMPV),a paramyxovirus,causes acute respiratory diseases in turkeys and swollen head syndrome in chickens.This study established a reverse genetics system for aMPV subtype B LN16-A strain based on...Avian metapneumovirus(aMPV),a paramyxovirus,causes acute respiratory diseases in turkeys and swollen head syndrome in chickens.This study established a reverse genetics system for aMPV subtype B LN16-A strain based on T7 RNA polymerase.Full-length cDNA of the LN16-A strain was constructed by assembling 5 cDNA fragments between the T7 promoter and hepatitis delta virus ribozyme.Transfection of this plasmid,along with the supporting plasmids encoding the N,P,M2-1,and L proteins of LN16-A into BSR-T7/5 cells,resulted in the recovery of aMPV subtype B.To identify an effective insertion site,the enhanced green fluorescent protein(EGFP)gene was inserted into different sites of the LN16-A genome to generate recombinant LN16-As.The results showed that the expression levels of EGFP at the site between the G and L genes of LN16-A were significantly higher than those at the other two sites(between the leader and N genes or replacing the SH gene).To verify the availability of the site between G and L for foreign gene expression,the VP2 gene of very virulent infectious bursal disease virus(vvIBDV)was inserted into this site,and recombinant LN16-A(rLN16A-vvVP2)was successfully rescued.Single immunization of specificpathogen-free chickens with rLN16A-vvVP2 induced high levels of neutralizing antibodies and provided 100%protection against the virulent aMPV subtype B and vvIBDV.Establishing a reverse genetics system here provides an important foundation for understanding aMPV pathogenesis and developing novel vector vaccines.展开更多
Deforestation remains one of the most imminent threats to biodiversity in the tropics.As such,its causes and dynamics need to be studied and understood to put a halt to further forest loss and degradation.In tropical ...Deforestation remains one of the most imminent threats to biodiversity in the tropics.As such,its causes and dynamics need to be studied and understood to put a halt to further forest loss and degradation.In tropical countries such as Uganda,agricultural expansion and wood fuel demand are its leading drivers.While the establishment of protected areas is a key tool in conserving remaining forest biodiversity,results indicate that current management does not sufficiently provide alternatives to forest resources utilised by households and income provided from timber and non-timber forest products.Beyond safeguarding ecosystems,protected areas need to ensure the sustainable socioeconomic development of adjacent communities for effective biodiversity conservation–however,both management and research often neglect to consider all dimensions.In this study,we analysed five decades of forest cover change in the Mount Elgon region,Uganda,by conducting a remote sensing analysis of its protected areas using Landsat MSS and TM data from 1973-2023 in combination with literature and subsequent interview analysis to consider both the ecological and socioeconomic dimension.We applied a random forest approach to differentiate forest and non-forest areas and carried out a pixel-based change detection analysis to differentiate temporal and spatial changes.Throughout the study period of 50 years,forest cover has evolved dynamically within the boundaries of the protected areas of Mount Elgon.A significant decline was observed in both Mount Elgon National Park with a loss of-5.98%(-46.83km²)and Mount Elgon Biosphere Reserve with a loss of-14.96%(-134.33km²).Our results showcase a cycle of deforestation and afforestation that could be tied to a series of development initiatives,re-demarcation of boundaries,changes in management and recurring evictions.Overall,the results lead to the conclusion that the lack of sustainable and efficient management and funding has fostered the rate of deforestation and accelerated ecological degradation in the region,but that existing problems are also rooted in the land tenure history of the region.We recommend the proper implementation of participatory and long-term management approaches on the ground and to address the land rights issue to contribute to both socioeconomic wellbeing and sustainable conservation outcomes.展开更多
This paper is concerned with a diffusive Ivlev-type predator-prey system with Smith growth and a protection zone. By discussing the existence and non-existence of positive solutions,we discover that the incorporation ...This paper is concerned with a diffusive Ivlev-type predator-prey system with Smith growth and a protection zone. By discussing the existence and non-existence of positive solutions,we discover that the incorporation of the Smith growth function has enabled us to obtain a more precise criterion when judging the structure of bifurcation solutions, and determine a critical size for the protection zone. The results indicate that if the size of the protection zone is below the critical patch size, then the system has no positive steady state solution for excessively high intrinsic growth rates of predators. Conversely, if the size of the protection zone exceeds the critical patch size, there exists positive steady state solution regardless of how large the intrinsic growth rate of the predators is.展开更多
Establishing and maintaining protected areas is a pivotal strategy for attaining the post-2020 biodiversity target. The conservation objectives of protected areas have shifted from a narrow emphasis on biodiversity to...Establishing and maintaining protected areas is a pivotal strategy for attaining the post-2020 biodiversity target. The conservation objectives of protected areas have shifted from a narrow emphasis on biodiversity to encompass broader considerations such as ecosystem stability, community resilience to climate change, and enhancement of human well-being. Given these multifaceted objectives, it is imperative to judiciously allocate resources to effectively conserve biodiversity by identifying strategically significant areas for conservation, particularly for mountainous areas. In this study, we evaluated the representativeness of the protected area network in the Qin ling Mountains concerning species diversity, ecosystem services, climate stability and ecological stability. The results indicate that some of the ecological indicators are spatially correlated with topographic gradient effects. The conservation priority areas predominantly lie in the northern foothills, the southeastern, and southwestern parts of the Qinling Mountain with areas concentrated at altitudes between 1,500-2,000 m and slopes between 40°-50° as hotspots. The conservation priority areas identified through the framework of inclusive conservation optimization account for 22.9 % of the Qinling Mountain. Existing protected areas comprise only 6.1 % of the Qinling Mountain and 13.18 % of the conservation priority areas. This will play an important role in achiev ing sustainable development in the region and in meeting the post-2020 biodiversity target. The framework can advance the different objectives of achieving a quadruple win and can also be extended to other regions.展开更多
With the continuous improvement of current science and technology and residents’electricity demand,the power system relay protection course has become a key component of the curriculum for students majoring in power ...With the continuous improvement of current science and technology and residents’electricity demand,the power system relay protection course has become a key component of the curriculum for students majoring in power engineering.In this context,the teaching model of power system relay protection faces both new challenges and opportunities.By integrating the Outcome-Based Education(OBE)concept,teachers can reconstruct curriculum objectives and teaching frameworks by clearly defining learning outcomes,thereby enhancing students’practical competencies and innovative thinking.Based on the core connotation of the OBE concept,this paper analyzes the significance of incorporating OBE into Power System Relay Protection teaching and explores effective implementation strategies.The findings aim to offer practical insights for teaching reform and to strengthen the alignment between academic training and industry requirements.展开更多
Marine protected areas(MPAs)play a critical role in maintaining marine ecosystem health,conserving biodiversity,and sustaining coastal livelihoods and socio-economic benefits.However,MPAs in China still face significa...Marine protected areas(MPAs)play a critical role in maintaining marine ecosystem health,conserving biodiversity,and sustaining coastal livelihoods and socio-economic benefits.However,MPAs in China still face significant design and management limitations,including a lack of a robust scientific basis for boundary delineation,weak enforcement capacity,poor adaptability to environmental and socio-economic changes,and insufficient integration of the ocean’s three-dimensional characteristics.These limitations are particularly evident in the context of climate change,overexploitation of marine resources,and the complex dynamics of ecosystems.This study systematically reviews the current status and challenges of MPAs in China,with a specific focus on the need for and benefits of dynamic and threedimensional protected areas for marine conservation.Dynamic protected areas,supported by real-time monitoring and flexible boundary adjustments,can more effectively respond to the migratory patterns of marine species and seasonal distribution shifts along China’s coast.On the other hand,three-dimensional protected areas enhance ecosystem protection by incorporating vertical ecological gradients and ocean depth,offering a vital complement to the predominantly two-dimensional protection approach currently in use.The study indicates that,with current technological and data capabilities,effective implementation of these advanced approaches requires precision marine observations,advanced analysis methods,and coordinated efforts among diverse stakeholders.In response,the study synthesizes multiple case studies to illustrate the potential ecological,managerial,and policy-related outcomes of dynamic and three-dimensional MPAs.It proposes strategies for optimization,implementation pathways,and targeted policy recommendations.Ultimately,the study emphasizes the critical role of scientific planning and technological innovation in enhancing the effectiveness of MPAs in China.It calls upon policymakers and the broader society to increase attention and investment in dynamic and three-dimensional marine conservation approaches.This work not only provides a scientific foundation for more precise and efficient marine governance in China,but also lays crucial foundation for achieving ocean-related sustainable development goals aligned with China’s national context.展开更多
With the rapid development of Internet of things technology,the efficiency of data transmission between devices has been significantly improved.However,the open network environment also poses serious security risks.Th...With the rapid development of Internet of things technology,the efficiency of data transmission between devices has been significantly improved.However,the open network environment also poses serious security risks.This paper proposes an innovative fingerprint template protection scheme,which generates key streams through an improved fourdimensional superchaotic system(4CSCS),uses the space-filling property of Hilbert curves to achieve pixel scrambling,and introduces dynamic DNA encoding to improve encryption.Experimental results show that this scheme has a large key space 2^(528),encrypts image information entropy of more than 7.9970,and shows excellent performance in defending against statistical attacks and differential attacks.Compared with existing methods,this scheme has significant advantages in terms of encryption performance and security,and provides a reliable protection mechanism for fingerprint authentication systems in the Internet of things environment.展开更多
This paper focused on the design and optimization of automatic sprinkler fire extinguishing systems in building fire protection.It was emphasized the importance of considering various factors in design,such as fire ri...This paper focused on the design and optimization of automatic sprinkler fire extinguishing systems in building fire protection.It was emphasized the importance of considering various factors in design,such as fire risk assessment and space utilization.Optimization strategies include enhancing water and energy efficiency,using ecofriendly materials,and smart monitoring.Practical implementation and validation in different building types were presented,along with performance benchmark analysis.Balancing fire safety and resource utilization is crucial,and future research in AI driven tuning and nano materials was promising.展开更多
In a deeply aging society,the appointed guardianship system,as an important arrangement for the protection of the rights and interests of the elderly,still faces many practical difficulties.Typical examples include:du...In a deeply aging society,the appointed guardianship system,as an important arrangement for the protection of the rights and interests of the elderly,still faces many practical difficulties.Typical examples include:during the decision-making stage of whether to choose appointed guardianship,the lack of professionalism and availability of appointed guardians can easily hinder the elderly from choosing to apply it;during the establishment stage of appointed guardianship,the limited rules related to the appointed guardianship agreement can easily lead to the frustration of the elderly’s subjective will;during the operation stage of appointed guardianship,the insufficient accountability mechanisms for appointed guardians can easily lead to the infringement of the personal or property rights of the elderly.By reflecting on its jurisprudential causes,it can be found that the current law largely ignores the orientation of appointed guardianship as a welfare for the elderly in social law,the concept of substantive equality in the appointed guardianship agreement,and the theoretical attributes of the appointed guardianship as a fiduciary relationship.Therefore,the appointed guardianship system in China should be systematically improved to fully release its institutional potential in the protection of the rights and interests of the elderly based on these jurisprudential principles.In particular,it is possible to consider actively promoting the“trust+appointed guardianship”model and cultivating a team of appointed guardians by the state based on the concept of elderly welfare;strengthening the protection of notarization procedures and the reasonable design of the appointed guardianship agreement based on the concept of substantive equality;and refining the fiduciary standards of appointed guardians and strengthening guardianship supervision based on the nature of fiduciary relationship.展开更多
BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking rec...BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking recovery.OBJECTIVE:To determine whether early suspension-protected training with a personal assistant machine for stroke patients enhances walking ability and prevents muscle spasms.METHODS:Thirty-two early-stage stroke patients from Shenzhen University General Hospital and the China Rehabilitation Research Center were randomly assigned to the experimental group(n=16)and the control group(n=16).Both groups underwent 4 weeks of gait training under the suspension protection system for 30 minutes daily,5 days a week.The experimental group used the personal assistant machine during training.Three-dimensional gait analysis(using the Cortex motion capture system),Brunnstrom staging,Fugl-Meyer Assessment for lower limb motor function,Fugl-Meyer balance function,and the modified Ashworth Scale were evaluated within 1 week before the intervention and after 4 weeks of intervention.RESULTS AND CONCLUSION:After the 4-week intervention,all outcome measures showed significant changes in each group.The experimental group had a small but significant increase in the modified Ashworth Scale score(P<0.05,d=|0.15|),while the control group had a large significant increase(P<0.05,d=|1.48|).The experimental group demonstrated greater improvements in walking speed(16.5 to 38.44 cm/s,P<0.05,d=|4.01|),step frequency(46.44 to 64.94 steps/min,P<0.05,d=|2.32|),stride length(15.50 to 29.81 cm,P<0.05,d=|3.44|),and peak hip and knee flexion(d=|1.82|to|2.17|).After treatment,the experimental group showed significantly greater improvements than the control group in walking speed(38.44 vs.26.63 cm/s,P<0.05,d=|2.75|),stride length,peak hip and knee flexion(d=|1.31|to|1.45|),step frequency(64.94 vs.59.38 steps/min,P<0.05,d=|0.85|),and a reduced support phase(bilateral:24.31%vs.28.38%,P<0.05,d=|0.88|;non-paretic:66.19%vs.70.13%,P<0.05,d=|0.94|).For early hemiplegia,personal assistant machine-assisted gait training under the suspension protection system helps establish a correct gait pattern,prevents muscle spasms,and improves motor function.展开更多
Objective: To investigate the efficacy of multidimensional protective nursing interventions in reducing occupational exposure risks to hydrofluoric acid in dental departments. Methods: The study was conducted between ...Objective: To investigate the efficacy of multidimensional protective nursing interventions in reducing occupational exposure risks to hydrofluoric acid in dental departments. Methods: The study was conducted between January 2024 and January 2025, involving 60 healthcare workers who were randomly assigned to groups. The control group (n = 30) received conventional occupational protective nursing care, while the observation group underwent multidimensional protective nursing interventions. Results: Following intervention, the observation group demonstrated significantly higher scores than the control group in knowledge of hydrofluoric acid occupational exposure, occupational exposure risk perception, and protective skill operation (p < 0.05). Emergency response capability scores and protective behavior implementation scores were also higher in the observation group (p < 0.05). Compared to the control group, the observation group exhibited higher occupational health satisfaction rates and lower occupational exposure incidence rates (p < 0.05). Conclusion: Multidimensional protective nursing interventions effectively enhance dental healthcare personnel’s awareness and protective capabilities regarding hydrofluoric acid occupational exposure, improve compliance with protective measures, and significantly reduce occupational exposure risks. This approach warrants promotion and application in occupational protective nursing interventions within dental departments.展开更多
基金supported by grants from the National Key R&D Program of China(No.2022YFB3709100)。
文摘In this study,an integrated thermal protection system was formed by bonding the Carbon/Carbon(C/C) composite thermal insulation layer and carbon foam thermal insulation tile on an aluminum honeycomb sandwich panel according to the functions of each layer of materials,and the thermal–mechanical response was analyzed by experimental tests and numerical simulations.First,infrared lamp facility and arcjet wind tunnel tests were used to check the accuracy of the model and calculate the heat-shielding index.Then,using the aerodynamic heat flow and pressure of the vehicles re-entry process,the temperature field and thermal deformation of the thermal protection system were analyzed according to the thermal–mechanical coupling analysis,and its performance requirements as a vehicles shell were evaluated.Analysis show that the thermomechanical properties of each layer were mismatched due to thermal deformation,resulting in debonding at the interlayer interface,which was also observed in the experiment.In addition,a 1 mm gap in the insulation tile promotes the release of thermal stress and reduces interlayer disbonding.According to the multi-scale model,10 thermal cycles(corresponding to the flight process) were analyzed,and the failure and damage evolution process of C/C composites at the microscopic level were revealed.The results of thermal cycling show that the microscopic damage started from the interfacial debonding of the fiber/matrix and ended with the connection of the pores through crack propagation in the matrix.This study provides a solution for analyzing the thermal–mechanical response of a thermal protection system and a design solution for improving reusability.
基金supported by the CIRP-5G Project(Business Finland)(No.6937/31/2021)the Otto A.Malm Foundation.
文摘Power system protection has evolved significantly due to the ongoing energy transition and digitalization.The development and standardization of information and communication technologies(ICTs)used for power system protection,monitoring,and control have led to the digitalization of substations and the introduction of new protection and control schemes.These include virtualized centralized protection and control for in-tra-substation applications,as well as advanced wide-area monitoring,protection,and control(WAMPAC)for inter-substation applications.This paper reviews the development of virtualized centralized protection,with a focus on key practical advancements,emerging technolo-gies,and state-of-the-art studies in centralized protection and control(CPC)and WAMPAC systems.It also identifies directions for future research.
文摘Objective To study the drug test data protection system in foreign countries,and to foster pharmaceutical innovation and increase drug accessibility in China.Methods The development history of drug test data protection was analyzed to examine and evaluate China’s current drug test data protection system so as to offer recommendations for its improvement.Finally,the drug test data protection system in China can be officially implemented.Results and Conclusion The drug test data protection system aims to promote innovation by protecting the trial data of innovative drugs.In a broad sense,this belongs to intellectual property protection,but it is different from patent protection.Although China has established a drug testing data protection system after joining the“Agreement on Trade-Related Aspects of Intellectual Property Rights(TRIPS)”,the relevant provisions and regulations have not yet been formally formed,and the system has not yet been implemented.Therefore,some suggestions for improving China’s drug testing data protection system are proposed to achieve good social benefits.
基金financial support from the National Key Research and Development Program(Grant No.2024YFA1209801)the National Natural Science Foundation of China(Grant Nos.12302140,12325204)+4 种基金the China Postdoctoral Science Foundation(Grant No.2023M732794)the Fundamental Research Funds for the Central Universities of China(Grant No.sxzy012023213)the Scientific Research Program of Shaanxi Province(Grant No.2023JC-XJ-02)the Young Talent Support Program of Xi'an Science and Technology Association(Grant No.959202413069)Postdoctoral Fellowship Program(Grade B)of China Postdoctoral Science Foundation(Grant No.GZB20230575)。
文摘Hypervelocity rocket sled systems are critical for testing advanced military technologies,yet track damage at speeds exceeding Mach 5 remains a significant challenge for system reliability and performance.In this study,we investigated the hypervelocity impact response and protection for highstrength U71 Mn or bainitic steel used in rocket sled tracks.Flyer plate impact experiments using a two-stage light-gas gun were conducted to study the hypervelocity collision response,followed by the microstructural characterization via optical microscope,scanning electron microscopy equipped with electron backscatter diffraction to reveal underlying damage mechanisms.Then,the calibrated thermalmechanical coupled finite element simulations using the Johnson-Cook constitutive model and MieGrüneisen equation of state were carried out.Results indicated that bainitic steel exhibits superior impact resistance with predominantly smooth scratch-dominated damage due to its higher ductility.In contrast,U71 Mn suffered significant material spallation and crack propagation arising from brittle fracture mechanisms.Zinc-rich epoxy primer coatings effectively mitigated stress concentration and temperature rise in the substrate at impacting velocities below 2.4 km/s,so as to suppress the microstructural damage such as adiabatic shear bands and dynamic recrystallization.However,coating protection diminished at ultra-high-speed impacts due to the coating failure.Dimensional analysis established quantitative relationships of the gouge damage size to projectile mass,impact velocity,and material yield strength.This study provides in-depth insights into damage mechanisms in hypervelocity rail systems,demonstrating that bainitic steel combined with protective coatings can significantly enhance impact resistance and system reliability,offering valuable guidance for the design and optimization of hypervelocity testing platforms.
基金supported by the National Natural Science Foundation of China(Nos.52107126 and52077179)the Key Regional Innovation and Development Joint Fund Project(No.2023YFB2303901)the funding of Chengdu Guojia Electrical Engineering Co.,Ltd.(No.NEEC-2022-B11).
文摘The regenerative braking energy utilization system(RBEUS)stands as a promising technique for improving the efficiency and power quality of electrified railways.Beyond the vital aspects of energy management and control strategies,ensuring fault protection is paramount for the secure and steady operation of the traction power supply system(TPSS)integrated with RBEUS.This paper introduces an innovative protection scheme tailored to diverse RBEUS application scenarios.Firstly,fault categories are streamlined into three levels:system,equipment,and warning.Subsequently,a novel multi-port active power differential protection method,aligned with RBEUS operational principles,is crafted to serve as a comprehensive and sensitive main protection.Building upon this foundation,a hierarchical protection structure for RBEUS is established,addressing the intricacies and variations in fault types while boosting anti-disturbance capabilities under faulty conditions.Embracing the principle of railway-oriented safety,a collaborative RBEUS-TPSS protection scheme is put forth.Finally,through simulated scenarios encompassing various fault conditions,the proposed scheme’s feasibility and effectiveness are convincingly validated.
基金supported by the Dong-A University of the Republic of Korea research fund。
文摘With the increasing demand for secure infrastructure such as hydrogen refueling stations,chemical plants,and energy storage systems,the need for protective structures capable of withstanding close-in detonations has become more critical.Existing design guidelines for protective walls(e.g.,UFC 3-340-02)primarily address mid-and far-field explosions,providing limited insights into near-field effects.Considering the effect of slight slopes(<40°)on reducing maximum reflected overpressure is deemed negligible.This study investigated the effectiveness of a reinforced concrete(RC)modular protection system(MPS)incorpo rating a diagonally tapered wall in attenuating re flected overpressures from closein detonations.Full-scale field experiments using a 51.3 kg TNT charge,representing the explosion energy of a typical hydrogen vessel rupture,demonstrated that a wall with a 7°slope significantly outperformed a vertical wall of equivalent concrete volume in terms of blast resistance.Observed structural responses included cracking,horizontal shear failure,and overturning.Complementary simulations using a validated computational fluid dynamics(CFD)model showed that the tapered wall reduced peak overpressure by 30%-40%compared to an equivalent vertical wall.This result highlights the potential of minor geometric modifications to enhance blast resilience.The tapered design effectively redirects incident blast waves,reducing localized damage while also conserving material,thus preserving modular benefits such as ease of transport and reusability.These findings suggest that diagonally tapered RC-based MPSs can offer a practical and resilient solution for industrial and military applications subject to near-field or sequential blast threats.
文摘This article takes the current autonomous driving technology as the research background and studies the collaborative protection mechanism between its system-on-chip(SoC)functional safety and information security.It includes an introduction to the functions and information security of autonomous driving SoCs,as well as the main design strategies for the collaborative prevention and control mechanism of SoC functional safety and information security in autonomous driving.The research shows that in the field of autonomous driving,there is a close connection between the functional safety of SoCs and their information security.In the design of the safety collaborative protection mechanism,the overall collaborative protection architecture,SoC functional safety protection mechanism,information security protection mechanism,the workflow of the collaborative protection mechanism,and its strategies are all key design elements.It is hoped that this analysis can provide some references for the collaborative protection of SoC functional safety and information security in the field of autonomous driving,so as to improve the safety of autonomous driving technology and meet its practical application requirements.
文摘1.Introduction to ablative TPS The Mars 2020 mission underscored the critical role of ablative Thermal Protection Systems(TPS)during atmospheric entry,where spacecraft encounter extreme aerodynamic heating.Established in the mid-20th century,blunt body theories led to the creation of ablative heat shields that effectively manage thermal loads through thermo-chemo-mechanical decomposition.This paper revisits the development and application of ablative TPS materials,which are single-mission solutions capable of withstanding entry velocities surpassing 10 km/s.
文摘The protection system for traditional Chinese medicine(TCM)varieties,as an important policy tool to promote the development of TCM,has a long history of over 30 years,from the promulgation of the“Regulations on the Protection of Traditional Chinese Medicine Varieties”in 1992 to the comprehensive revision of the draft for soliciting opinions in 2022.The TCM protection system evolves to meet the needs of innovative development of TCM.This paper reviews the policy developments in TCM varieties protection,collates protection data(1993 to 2024),and analyzes enterprises application strategies amid impending regulatory changes.
基金supported by the grants from the National Key Research and Development Program of China(2022YFD1800604)the China Agriculture Research System(CARS-41)the Heilongjiang Touyan Innovation Team Program,China。
文摘Avian metapneumovirus(aMPV),a paramyxovirus,causes acute respiratory diseases in turkeys and swollen head syndrome in chickens.This study established a reverse genetics system for aMPV subtype B LN16-A strain based on T7 RNA polymerase.Full-length cDNA of the LN16-A strain was constructed by assembling 5 cDNA fragments between the T7 promoter and hepatitis delta virus ribozyme.Transfection of this plasmid,along with the supporting plasmids encoding the N,P,M2-1,and L proteins of LN16-A into BSR-T7/5 cells,resulted in the recovery of aMPV subtype B.To identify an effective insertion site,the enhanced green fluorescent protein(EGFP)gene was inserted into different sites of the LN16-A genome to generate recombinant LN16-As.The results showed that the expression levels of EGFP at the site between the G and L genes of LN16-A were significantly higher than those at the other two sites(between the leader and N genes or replacing the SH gene).To verify the availability of the site between G and L for foreign gene expression,the VP2 gene of very virulent infectious bursal disease virus(vvIBDV)was inserted into this site,and recombinant LN16-A(rLN16A-vvVP2)was successfully rescued.Single immunization of specificpathogen-free chickens with rLN16A-vvVP2 induced high levels of neutralizing antibodies and provided 100%protection against the virulent aMPV subtype B and vvIBDV.Establishing a reverse genetics system here provides an important foundation for understanding aMPV pathogenesis and developing novel vector vaccines.
基金The financial support by the Deutsche Bundesstiftung Umwelt (DBU)
文摘Deforestation remains one of the most imminent threats to biodiversity in the tropics.As such,its causes and dynamics need to be studied and understood to put a halt to further forest loss and degradation.In tropical countries such as Uganda,agricultural expansion and wood fuel demand are its leading drivers.While the establishment of protected areas is a key tool in conserving remaining forest biodiversity,results indicate that current management does not sufficiently provide alternatives to forest resources utilised by households and income provided from timber and non-timber forest products.Beyond safeguarding ecosystems,protected areas need to ensure the sustainable socioeconomic development of adjacent communities for effective biodiversity conservation–however,both management and research often neglect to consider all dimensions.In this study,we analysed five decades of forest cover change in the Mount Elgon region,Uganda,by conducting a remote sensing analysis of its protected areas using Landsat MSS and TM data from 1973-2023 in combination with literature and subsequent interview analysis to consider both the ecological and socioeconomic dimension.We applied a random forest approach to differentiate forest and non-forest areas and carried out a pixel-based change detection analysis to differentiate temporal and spatial changes.Throughout the study period of 50 years,forest cover has evolved dynamically within the boundaries of the protected areas of Mount Elgon.A significant decline was observed in both Mount Elgon National Park with a loss of-5.98%(-46.83km²)and Mount Elgon Biosphere Reserve with a loss of-14.96%(-134.33km²).Our results showcase a cycle of deforestation and afforestation that could be tied to a series of development initiatives,re-demarcation of boundaries,changes in management and recurring evictions.Overall,the results lead to the conclusion that the lack of sustainable and efficient management and funding has fostered the rate of deforestation and accelerated ecological degradation in the region,but that existing problems are also rooted in the land tenure history of the region.We recommend the proper implementation of participatory and long-term management approaches on the ground and to address the land rights issue to contribute to both socioeconomic wellbeing and sustainable conservation outcomes.
基金Supported by the National Natural Science Foundation of China(Grant No.12161080)。
文摘This paper is concerned with a diffusive Ivlev-type predator-prey system with Smith growth and a protection zone. By discussing the existence and non-existence of positive solutions,we discover that the incorporation of the Smith growth function has enabled us to obtain a more precise criterion when judging the structure of bifurcation solutions, and determine a critical size for the protection zone. The results indicate that if the size of the protection zone is below the critical patch size, then the system has no positive steady state solution for excessively high intrinsic growth rates of predators. Conversely, if the size of the protection zone exceeds the critical patch size, there exists positive steady state solution regardless of how large the intrinsic growth rate of the predators is.
基金supported by the National Natural Science Foun-dation of China(Grant No.72349002).
文摘Establishing and maintaining protected areas is a pivotal strategy for attaining the post-2020 biodiversity target. The conservation objectives of protected areas have shifted from a narrow emphasis on biodiversity to encompass broader considerations such as ecosystem stability, community resilience to climate change, and enhancement of human well-being. Given these multifaceted objectives, it is imperative to judiciously allocate resources to effectively conserve biodiversity by identifying strategically significant areas for conservation, particularly for mountainous areas. In this study, we evaluated the representativeness of the protected area network in the Qin ling Mountains concerning species diversity, ecosystem services, climate stability and ecological stability. The results indicate that some of the ecological indicators are spatially correlated with topographic gradient effects. The conservation priority areas predominantly lie in the northern foothills, the southeastern, and southwestern parts of the Qinling Mountain with areas concentrated at altitudes between 1,500-2,000 m and slopes between 40°-50° as hotspots. The conservation priority areas identified through the framework of inclusive conservation optimization account for 22.9 % of the Qinling Mountain. Existing protected areas comprise only 6.1 % of the Qinling Mountain and 13.18 % of the conservation priority areas. This will play an important role in achiev ing sustainable development in the region and in meeting the post-2020 biodiversity target. The framework can advance the different objectives of achieving a quadruple win and can also be extended to other regions.
文摘With the continuous improvement of current science and technology and residents’electricity demand,the power system relay protection course has become a key component of the curriculum for students majoring in power engineering.In this context,the teaching model of power system relay protection faces both new challenges and opportunities.By integrating the Outcome-Based Education(OBE)concept,teachers can reconstruct curriculum objectives and teaching frameworks by clearly defining learning outcomes,thereby enhancing students’practical competencies and innovative thinking.Based on the core connotation of the OBE concept,this paper analyzes the significance of incorporating OBE into Power System Relay Protection teaching and explores effective implementation strategies.The findings aim to offer practical insights for teaching reform and to strengthen the alignment between academic training and industry requirements.
基金The National Natural Science Foundation of China under contract No.42176173.
文摘Marine protected areas(MPAs)play a critical role in maintaining marine ecosystem health,conserving biodiversity,and sustaining coastal livelihoods and socio-economic benefits.However,MPAs in China still face significant design and management limitations,including a lack of a robust scientific basis for boundary delineation,weak enforcement capacity,poor adaptability to environmental and socio-economic changes,and insufficient integration of the ocean’s three-dimensional characteristics.These limitations are particularly evident in the context of climate change,overexploitation of marine resources,and the complex dynamics of ecosystems.This study systematically reviews the current status and challenges of MPAs in China,with a specific focus on the need for and benefits of dynamic and threedimensional protected areas for marine conservation.Dynamic protected areas,supported by real-time monitoring and flexible boundary adjustments,can more effectively respond to the migratory patterns of marine species and seasonal distribution shifts along China’s coast.On the other hand,three-dimensional protected areas enhance ecosystem protection by incorporating vertical ecological gradients and ocean depth,offering a vital complement to the predominantly two-dimensional protection approach currently in use.The study indicates that,with current technological and data capabilities,effective implementation of these advanced approaches requires precision marine observations,advanced analysis methods,and coordinated efforts among diverse stakeholders.In response,the study synthesizes multiple case studies to illustrate the potential ecological,managerial,and policy-related outcomes of dynamic and three-dimensional MPAs.It proposes strategies for optimization,implementation pathways,and targeted policy recommendations.Ultimately,the study emphasizes the critical role of scientific planning and technological innovation in enhancing the effectiveness of MPAs in China.It calls upon policymakers and the broader society to increase attention and investment in dynamic and three-dimensional marine conservation approaches.This work not only provides a scientific foundation for more precise and efficient marine governance in China,but also lays crucial foundation for achieving ocean-related sustainable development goals aligned with China’s national context.
文摘With the rapid development of Internet of things technology,the efficiency of data transmission between devices has been significantly improved.However,the open network environment also poses serious security risks.This paper proposes an innovative fingerprint template protection scheme,which generates key streams through an improved fourdimensional superchaotic system(4CSCS),uses the space-filling property of Hilbert curves to achieve pixel scrambling,and introduces dynamic DNA encoding to improve encryption.Experimental results show that this scheme has a large key space 2^(528),encrypts image information entropy of more than 7.9970,and shows excellent performance in defending against statistical attacks and differential attacks.Compared with existing methods,this scheme has significant advantages in terms of encryption performance and security,and provides a reliable protection mechanism for fingerprint authentication systems in the Internet of things environment.
文摘This paper focused on the design and optimization of automatic sprinkler fire extinguishing systems in building fire protection.It was emphasized the importance of considering various factors in design,such as fire risk assessment and space utilization.Optimization strategies include enhancing water and energy efficiency,using ecofriendly materials,and smart monitoring.Practical implementation and validation in different building types were presented,along with performance benchmark analysis.Balancing fire safety and resource utilization is crucial,and future research in AI driven tuning and nano materials was promising.
基金the National Social Science Fund of China Youth Project“Research on the Application Dilemma and Solutions of the Appointed Guardianship Clauses in the Civil Code”(Project Approval Number 20CFX075).
文摘In a deeply aging society,the appointed guardianship system,as an important arrangement for the protection of the rights and interests of the elderly,still faces many practical difficulties.Typical examples include:during the decision-making stage of whether to choose appointed guardianship,the lack of professionalism and availability of appointed guardians can easily hinder the elderly from choosing to apply it;during the establishment stage of appointed guardianship,the limited rules related to the appointed guardianship agreement can easily lead to the frustration of the elderly’s subjective will;during the operation stage of appointed guardianship,the insufficient accountability mechanisms for appointed guardians can easily lead to the infringement of the personal or property rights of the elderly.By reflecting on its jurisprudential causes,it can be found that the current law largely ignores the orientation of appointed guardianship as a welfare for the elderly in social law,the concept of substantive equality in the appointed guardianship agreement,and the theoretical attributes of the appointed guardianship as a fiduciary relationship.Therefore,the appointed guardianship system in China should be systematically improved to fully release its institutional potential in the protection of the rights and interests of the elderly based on these jurisprudential principles.In particular,it is possible to consider actively promoting the“trust+appointed guardianship”model and cultivating a team of appointed guardians by the state based on the concept of elderly welfare;strengthening the protection of notarization procedures and the reasonable design of the appointed guardianship agreement based on the concept of substantive equality;and refining the fiduciary standards of appointed guardians and strengthening guardianship supervision based on the nature of fiduciary relationship.
文摘BACKGROUND:Hemiplegia,a prevalent stroke-related condition,is often studied for motor dysfunction;however,spasticity remains under-researched.Abnormal muscle tone significantly hinders hemiplegic patients’walking recovery.OBJECTIVE:To determine whether early suspension-protected training with a personal assistant machine for stroke patients enhances walking ability and prevents muscle spasms.METHODS:Thirty-two early-stage stroke patients from Shenzhen University General Hospital and the China Rehabilitation Research Center were randomly assigned to the experimental group(n=16)and the control group(n=16).Both groups underwent 4 weeks of gait training under the suspension protection system for 30 minutes daily,5 days a week.The experimental group used the personal assistant machine during training.Three-dimensional gait analysis(using the Cortex motion capture system),Brunnstrom staging,Fugl-Meyer Assessment for lower limb motor function,Fugl-Meyer balance function,and the modified Ashworth Scale were evaluated within 1 week before the intervention and after 4 weeks of intervention.RESULTS AND CONCLUSION:After the 4-week intervention,all outcome measures showed significant changes in each group.The experimental group had a small but significant increase in the modified Ashworth Scale score(P<0.05,d=|0.15|),while the control group had a large significant increase(P<0.05,d=|1.48|).The experimental group demonstrated greater improvements in walking speed(16.5 to 38.44 cm/s,P<0.05,d=|4.01|),step frequency(46.44 to 64.94 steps/min,P<0.05,d=|2.32|),stride length(15.50 to 29.81 cm,P<0.05,d=|3.44|),and peak hip and knee flexion(d=|1.82|to|2.17|).After treatment,the experimental group showed significantly greater improvements than the control group in walking speed(38.44 vs.26.63 cm/s,P<0.05,d=|2.75|),stride length,peak hip and knee flexion(d=|1.31|to|1.45|),step frequency(64.94 vs.59.38 steps/min,P<0.05,d=|0.85|),and a reduced support phase(bilateral:24.31%vs.28.38%,P<0.05,d=|0.88|;non-paretic:66.19%vs.70.13%,P<0.05,d=|0.94|).For early hemiplegia,personal assistant machine-assisted gait training under the suspension protection system helps establish a correct gait pattern,prevents muscle spasms,and improves motor function.
基金Construction of Standardized Protective Nursing Plan for Hydrofluoric Acid Operations in Dentistry and Research on Injury Prevention Effects(Project No.:FZ2025101)。
文摘Objective: To investigate the efficacy of multidimensional protective nursing interventions in reducing occupational exposure risks to hydrofluoric acid in dental departments. Methods: The study was conducted between January 2024 and January 2025, involving 60 healthcare workers who were randomly assigned to groups. The control group (n = 30) received conventional occupational protective nursing care, while the observation group underwent multidimensional protective nursing interventions. Results: Following intervention, the observation group demonstrated significantly higher scores than the control group in knowledge of hydrofluoric acid occupational exposure, occupational exposure risk perception, and protective skill operation (p < 0.05). Emergency response capability scores and protective behavior implementation scores were also higher in the observation group (p < 0.05). Compared to the control group, the observation group exhibited higher occupational health satisfaction rates and lower occupational exposure incidence rates (p < 0.05). Conclusion: Multidimensional protective nursing interventions effectively enhance dental healthcare personnel’s awareness and protective capabilities regarding hydrofluoric acid occupational exposure, improve compliance with protective measures, and significantly reduce occupational exposure risks. This approach warrants promotion and application in occupational protective nursing interventions within dental departments.
