The increasing demand for industrial automation and intelligence has put forward higher requirements for the reliability of industrial wireless communication technology.As an international standard based on 802.11,Wir...The increasing demand for industrial automation and intelligence has put forward higher requirements for the reliability of industrial wireless communication technology.As an international standard based on 802.11,Wireless networks for Industrial Automation-Factory Automation(WIA-FA)greatly improves the reliability in factory automation scenarios by Time Division Multiple Access(TDMA).However,in ultra-dense WIA-FA networks with mobile users,the basic connection management mechanism is inefficient.Most of the handover and resource management algorithms are all based on frequency division multiplexing,not suitable for the TDMA in the WIA-FA network.Therefore,we propose Load-aware Connection Management(LACM)algorithm to adjust the linkage and balance the load of access devices to avoid blocking and improve the reliability of the system.And then we simulate the algorithm to find the optimal settings of the parameters.After comparing with other existing algorithms,the result of the simulation proves that LACM is more efficient in reliability and maintains high reliability of more than 99.8%even in the ultra-dense moving scenario with 1500 field devices.Besides,this algorithm ensures that only a few signaling exchanges are required to ensure load bal-ancing,which is no more than 5 times,and less than half of the best state-of-the-art algorithm.展开更多
With the increasing attention paid to battery technology,the microscopic reaction mechanism and macroscopic heat transfer process of lithium-ion batteries have been further studied and understood from both academic an...With the increasing attention paid to battery technology,the microscopic reaction mechanism and macroscopic heat transfer process of lithium-ion batteries have been further studied and understood from both academic and industrial perspectives.Temperature,as one of the key parameters in the physical fra mework of batteries,affects the performa nce of the multi-physical fields within the battery,a nd its effective control is crucial.Since the heat generation in the battery is determined by the real-time operating conditions,the battery temperature is essentially controlled by the real-time heat dissipation conditions provided by the battery thermal management system.Conventional battery thermal management systems have basic temperature control capabilities for most conventional application scenarios.However,with the current development of la rge-scale,integrated,and intelligent battery technology,the adva ncement of battery thermal management technology will pay more attention to the effective control of battery temperature under sophisticated situations,such as high power and widely varied operating conditions.In this context,this paper presents the latest advances and representative research related to battery thermal management system.Firstly,starting from battery thermal profile,the mechanism of battery heat generation is discussed in detail.Secondly,the static characteristics of the traditional battery thermal management system are summarized.Then,considering the dynamic requirements of battery heat dissipation under complex operating conditions,the concept of adaptive battery thermal management system is proposed based on specific research cases.Finally,the main challenges for battery thermal management system in practice are identified,and potential future developments to overcome these challenges are presented and discussed.展开更多
Climate change and forest management are recognized as pivotal factors influencing forest ecosystem services and thus multifunctionality.However,the magnitude and the relative importance of climate change and forest m...Climate change and forest management are recognized as pivotal factors influencing forest ecosystem services and thus multifunctionality.However,the magnitude and the relative importance of climate change and forest management effects on the multifunctionality remain unclear,especially for natural mixed forests.In this study,our objective is to address this gap by utilizing simulations of climate-sensitive transition matrix growth models based on national forest inventory plot data.We evaluated the effects of seven management scenarios(combinations of various cutting methods and intensities)on the future provision of ecosystem services and multifunctionality in mixed conifer-broad-leaved forests in northeastern China,under four climate scenarios(SSP1-2.6,SSP2-4.5,SSP5-8.5,and constant climate).Provisioning,regulating,cultural,and supporting services were described by timber production,carbon storage,carbon sequestration,tree species diversity,deadwood volume,and the number of large living trees.Our findings indicated that timber production was significantly influenced by management scenarios,while tree species diversity,deadwood volume,and large living trees were impacted by both climate and management separately.Carbon storage and sequestration were notably influenced by both management and the interaction of climate and management.These findings emphasized the profound impact of forest management on ecosystem services,outweighing that of climate scenarios alone.We found no single management scenario maximized all six ecosystem service indicators.The upper story thinning by 5%intensity with 5-year interval(UST5)management strategy emerged with the highest multifunctionality,surpassing the lowest values by more than 20%across all climate scenarios.In conclusion,our results underlined the potential of climate-sensitive transition matrix growth models as a decision support tool and provided recommendations for long-term strategies for multifunctional forest management under future climate change context.Ecosystem services and multifunctionality of forests could be enhanced by implementing appropriate management measures amidst a changing climate.展开更多
All-season thermal management with zero energy consumption and emissions is more crucial to global decarbonization over traditional energy-intensive cooling/heating systems.However,the static single thermal management...All-season thermal management with zero energy consumption and emissions is more crucial to global decarbonization over traditional energy-intensive cooling/heating systems.However,the static single thermal management for cooling or heating fails to self-regulate the temperature in dynamic seasonal temperature condition.Herein,inspired by the dual-temperature regulation function of the fur color changes on the backs and abdomens of penguins,a smart thermal management composite hydrogel(PNA@H-PM Gel)system was subtly created though an"on-demand"dual-layer structure design strategy.The PNA@H-PM Gel system features synchronous solar and thermal radiation modulation as well as tunable phase transition temperatures to meet the variable seasonal thermal requirements and energy-saving demands via self-adaptive radiative cooling and solar heating regulation.Furthermore,this system demonstrates superb modulations of both the solar reflectance(ΔR=0.74)and thermal emissivity(ΔE=0.52)in response to ambient temperature changes,highlighting efficient temperature regulation with average radiative cooling and solar heating effects of 9.6℃in summer and 6.1℃in winter,respectively.Moreover,compared to standard building baselines,the PNA@H-PM Gel presents a more substantial energy-saving cooling/heating potentials for energy-efficient buildings across various regions and climates.This novel solution,inspired by penguins in the real world,will offer a fresh approach for producing intelligent,energy-saving thermal management materials,and serve for temperature regulation under dynamic climate conditions and even throughout all seasons.展开更多
High-temperature stealth is vital for enhancing the concealment,survivability,and longevity of critical assets.However,achieving stealth across multiple infrared bands—particularly in the short-wave infrared(SWIR)ban...High-temperature stealth is vital for enhancing the concealment,survivability,and longevity of critical assets.However,achieving stealth across multiple infrared bands—particularly in the short-wave infrared(SWIR)band—along with microwave stealth and efficient thermal management at high temperatures,remains a significant challenge.Here,we propose a strategy that integrates an IR-selective emitter(Mo/Si multilayer films)and a microwave metasurface(TiB2–Al2O3–TiB2)to enable multi-infrared band stealth,encompassing mid-wave infrared(MWIR),long-wave infrared(LWIR),and SWIR bands,and microwave(X-band)stealth at 700℃,with simultaneous radiative cooling in non-atmospheric window(5–8μm).At 700℃,the device exhibits low emissivity of 0.38/0.44/0.60 in the MWIR/LWIR/SWIR bands,reflection loss below−3 dB in the X-band(9.6–12 GHz),and high emissivity of 0.82 in 5–8μm range—corresponding to a cooling power of 9.57 kW m^(−2).Moreover,under an input power of 17.3 kW m^(−2)—equivalent to the aerodynamic heating at Mach 2.2—the device demonstrates a temperature reduction of 72.4℃ compared to a conventional low-emissivity molybdenum surface at high temperatures.This work provides comprehensive guidance on high-temperature stealth design,with far-reaching implications for multispectral information processing and thermal management in extreme high-temperature environments.展开更多
Thermal management system is highly desirable to guarantee the performance and thermal safety of lithium-ion batteries,but it reduces the energy density of battery modules and even is unable to provide highly effectiv...Thermal management system is highly desirable to guarantee the performance and thermal safety of lithium-ion batteries,but it reduces the energy density of battery modules and even is unable to provide highly effective protection.Here,a thermal management function integrated material is presented based on high-temperature resistant aerogel and phase change material and is applied at both charge–discharge process and thermal runaway condition.In this sandwich structure Paraffin@SiC nanowire/Aerogel sheet (denoted as PA@SAS) system,SiC nanowires endow the middle aerogel sheet (SAS) a dual nano-network structure.The enhanced mechanical properties of SAS were studied by compressive tests and dynamic mechanical analysis.Besides,the thermal conductivity of SAS at 600°C is only 0.042 W/(m K).The surface phase change material layers facilitate temperature uniformity of batteries (surface temperature difference less than 1.82°C) through latent heat.Moreover,a large-format battery module with four 58 Ah LiNi0.5Co0.2Mn0.3O2LIBs was assembled.PA@SAS successfully prevents thermal runaway propagation,yielding a temperature gap of 602°C through the 2 mm-thick cross section.PA@SAS also exhibits excellent performance in other safety issues such as temperature rise rate,flame heat flux,etc.The lightweight property and effective insulation performance achieves significant safety enhancement with mass and volume energy density reduction of only 0.79%and 5.4%,respectively.The originality of the present research stems from the micro and macro structure design of the proposed thermal management material and the combination of intrinsic advantages of every component.This work provides a reliable design of achieving the integration of thermal management functions into an aerogel composite and improves the thermal safety of lithium-ion batteries.展开更多
Climate change is the most severe ecological challenge faced by the world today.Forests,the dominant component of terrestrial ecosystems,play a critical role in mitigating climate change due to their powerful carbon s...Climate change is the most severe ecological challenge faced by the world today.Forests,the dominant component of terrestrial ecosystems,play a critical role in mitigating climate change due to their powerful carbon sequestration capabilities.Meanwhile,climate change has also become a major factor affecting the sustainable management of forest ecosystems.Climate-Smart Forestry(CSF)is an emerging concept in sustainable forest management.By utilizing advanced technologies,such as information technology and artificial intelligence,CSF aims to develop innovative and proactive forest management methods and decision-making systems to address the challenges of climate change.CSF aims to enhance forest ecosystem resilience(i.e.,maintain a condition where,even when the state of the ecosystem changes,the ecosystem functions do not deteriorate)through climate change adaptation,improve the mitigation capabilities of forest ecosystems to climate change,maintain high,stable,and sustainable forest productivity and ecosystem services,and ultimately achieve harmonious development between humans and nature.This concept paper:(1)discusses the emergence and development of CSF,which integrates Ecological Forestry,Carbon Forestry,and Smart Forestry,and proposes the concept of CSF;(2)analyzes the goals of CSF in improving forest ecosystem stability,enhancing forest ecosystem carbon sequestration capacity,and advocating the application and development of new technologies in CSF,including artificial intelligence,robotics,Light Detection and Ranging,and forest digital twin;(3)presents the latest practices of CSF based on prior research on forest structure and function using new generation information technologies at Qingyuan Forest,China.From these practices and reflections,we suggested the development direction of CSF,including the key research topics and technological advancement.展开更多
BACKGROUND: Targeted temperature management(TTM) is a common therapeutic intervention, yet its cost-effectiveness remains uncertain. This study aimed to evaluate the real-world cost-effectiveness of TTM compared with ...BACKGROUND: Targeted temperature management(TTM) is a common therapeutic intervention, yet its cost-effectiveness remains uncertain. This study aimed to evaluate the real-world cost-effectiveness of TTM compared with that of conventional care in adult out-of-hospital cardiac arrest(OHCA) survivors using clinical patient-level data.METHODS: We conducted a retrospective cohort study at an academic medical center in the USA to assess the cost-effectiveness of TTM in adult non-traumatic OHCA survivors between 1 January, 2019 and 30 June, 2023. The primary outcome was survival to hospital discharge. Incremental cost-effectiveness ratios(ICERs) were calculated and compared with various decision makers' willingness to pay. Cost-effectiveness acceptability curves were utilized to evaluate the economic attractiveness of TTM. Uncertainty about the incremental cost and effect was explored with a 95% confidence ellipse.RESULTS: Among 925 non-traumatic OHCA survivors, only 30(3%) received TTM. After adjusting for potential confounders, the TTM group did not demonstrate a significantly lower cost(delta cost-$5,141, 95% confidence interval [95% CI]: $-35,347 to $25,065, P=0.79) and higher survival to hospital discharge(delta effect 6%, 95% CI:-11% to 23%, P=0.41). Additionally, a 95% confidence ellipse indicated uncertainty reflected by evidence that the true value of the ICER could be in any of the quadrants of the cost-effectiveness plane.CONCLUSION: Although TTM did not demonstrate a clear survival benefit in this study, its potential cost-effectiveness warrants further investigation with larger sample sizes. These findings highlight the need for additional research to optimize TTM use in OHCA care and inform resource allocation decisions.展开更多
Radiative cooling fabric creates a thermally comfortable environment without energy input,providing a sustainable approach to personal thermal management.However,most currently reported fabrics mainly focus on outdoor...Radiative cooling fabric creates a thermally comfortable environment without energy input,providing a sustainable approach to personal thermal management.However,most currently reported fabrics mainly focus on outdoor cooling,ignoring to achieve simultaneous cooling both indoors and outdoors,thereby weakening the overall cooling performance.Herein,a full-scale structure fabric with selective emission properties is constructed for simultaneous indoor and outdoor cooling.The fabric achieves 94%reflectance performance in the sunlight band(0.3–2.5μm)and 6%in the mid-infrared band(2.5–25μm),effectively minimizing heat absorption and radiation release obstruction.It also demonstrates 81%radiative emission performance in the atmospheric window band(8–13μm)and 25%radiative transmission performance in the mid-infrared band(2.5–25μm),providing 60 and 26 W m−2 net cooling power outdoors and indoors.In practical applications,the fabric achieves excellent indoor and outdoor human cooling,with temperatures 1.4–5.5℃ lower than typical polydimethylsiloxane film.This work proposes a novel design for the advanced radiative cooling fabric,offering significant potential to realize sustainable personal thermal management.展开更多
Plenter forests,also known as uneven-aged or continuous cover forests enhance forest resilience and resistance against disturbances compared to even-aged forests.They are considered as an adaptation option to mitigate...Plenter forests,also known as uneven-aged or continuous cover forests enhance forest resilience and resistance against disturbances compared to even-aged forests.They are considered as an adaptation option to mitigate climate change effects.In this study,we present a conceptual approach to determine the potentially suitable area for plenter forest management within central European mixed species forests and apply our approach to the case study area in Styria,the south-eastern Province of Austria.The concept is based on ecological and technicaleconomic constraints and considers expected future climate conditions and its impact on plenter forest management.For each 1 ha forest pixel,we assess the ecological conditions for plenter forest management according to the autecological growth conditions of silver fir,and at least one additional shade tolerant tree species.The technical-economic constraints are defined by slope(≤30%)and distance to the next forest road(≤100 m)to ensure cost-efficient harvesting.The results show that under current climate conditions 28.1%or 305,349 ha of the forests in Styria are potentially suitable for plenter forest management.For the years 2071–2100 and under the climate change scenario RCP 4.5,the potential area decreases to 286,098 ha(26.3%of the total forest area)and for the scenario RCP 8.5 to 208,421 ha(19.1%of the total forest area).The main reason for these changes is the unfavourable growing conditions for silver fir in the lowlands,while in the higher elevations silver fir is likely to expand.Our results may serve forest managers to identify areas suitable for plenter forests and assist in the transformation of even-aged pure forests to uneven-aged forests to increase resistance,resilience,and biodiversity under climate change.展开更多
5G technology has endowed mobile communication terminals with features such as ultrawideband access,low latency,and high reliability transmission,which can complete the network access and interconnection of a large nu...5G technology has endowed mobile communication terminals with features such as ultrawideband access,low latency,and high reliability transmission,which can complete the network access and interconnection of a large number of devices,thus realizing richer application scenarios and constructing 5G-enabled vehicular networks.However,due to the vulnerability of wireless communication,vehicle privacy and communication security have become the key problems to be solved in vehicular networks.Moreover,the large-scale communication in the vehicular networks also makes the higher communication efficiency an inevitable requirement.In order to achieve efficient and secure communication while protecting vehicle privacy,this paper proposes a lightweight key agreement and key update scheme for 5G vehicular networks based on blockchain.Firstly,the key agreement is accomplished using certificateless public key cryptography,and based on the aggregate signature and the cooperation between the vehicle and the trusted authority,an efficient key updating method is proposed,which reduces the overhead and protects the privacy of the vehicle while ensuring the communication security.Secondly,by introducing blockchain and using smart contracts to load the vehicle public key table for key management,this meets the requirements of vehicle traceability and can dynamically track and revoke misbehaving vehicles.Finally,the formal security proof under the eck security model and the informal security analysis is conducted,it turns out that our scheme is more secure than other authentication schemes in the vehicular networks.Performance analysis shows that our scheme has lower overhead than existing schemes in terms of communication and computation.展开更多
With the deployment of ultra-dense low earth orbit(LEO)satellite constellations,LEO satellite access network(LEO-SAN)is envisioned to achieve global Internet coverage.Meanwhile,the civil aviation communications have i...With the deployment of ultra-dense low earth orbit(LEO)satellite constellations,LEO satellite access network(LEO-SAN)is envisioned to achieve global Internet coverage.Meanwhile,the civil aviation communications have increased dramatically,especially for providing airborne Internet services.However,due to dynamic service demands and onboard LEO resources over time and space,it poses huge challenges in satellite-aircraft access and service management in ultra-dense LEO satellite networks(UDLSN).In this paper,we propose a deep reinforcement learning-based approach for ultra-dense LEO satellite-aircraft access and service management.Firstly,we develop an airborne Internet architecture based on UDLSN and design a management mechanism including medium earth orbit satellites to guarantee lightweight management.Secondly,considering latency-sensitive and latency-tolerant services,we formulate the problem of satellite-aircraft access and service management for civil aviation to ensure service continuity.Finally,we propose a proximal policy optimization-based access and service management algorithm to solve the formulated problem.Simulation results demonstrate the convergence and effectiveness of the proposed algorithm with satisfying the service continuity when applying to the UDLSN.展开更多
Forest ecosystems are important for biodiversity conservation and human societies,but are under pressure due to climate change and human interventions.This applies to natural forests as well as tree plantations.The la...Forest ecosystems are important for biodiversity conservation and human societies,but are under pressure due to climate change and human interventions.This applies to natural forests as well as tree plantations.The latter are globally widespread and therefore gaining increasing importance for biodiversity conservation.However,even after dieback due to increasing disturbance frequencies,such plantations are primarily managed for economic returns,leading to growing conflicts among stakeholders.In particular,the impact of forest management on biodiversity is being discussed.This study investigates the effects of five management approaches in a landscape severely affected by spruce(Picea abies L.)dieback on beetle diversity,conservation,and community composition.We considered direct effects of management and indirect effects of environmental parameters separately in ground-dwelling and flight-active beetles.Beetle diversity was strongly affected by forest management,with nonintervention deadwood stands being most beneficial for beetles.In addition,we show indirect effects of environmental factors.In general,parameters related to salvage logging(e.g.open canopies,tree stumps)influenced beetle diversity and conservation negatively,while positive effects were found for soil nutrient availability and plant species richness.Community composition differed strongly among management categories and indicated a lack of landscape connectivity for open habitat species,as we found only low proportions of such species even on salvage-logged sites.We propose a mixture of management approaches after bark beetle outbreaks,including a substantial proportion of non-intervention deadwood stands,to increase landscape heterogeneity and connectivity.This may increase overall biodiversity while addressing the concerns of both forestry and species conservation.展开更多
Aim To research and develop a battery management system(BMS)with the state of charge(SOC)indicator for electric vehicles (EVs).Methods On the basis of analyzing the electro-chemical characteristics of lead-acid. batte...Aim To research and develop a battery management system(BMS)with the state of charge(SOC)indicator for electric vehicles (EVs).Methods On the basis of analyzing the electro-chemical characteristics of lead-acid. battery, the state of charge indicator for lead-acid battery was developed by means of an algorithm based on combination of ampere-hour, Peukert's equation and open-voltage method with the compensation of temperature,aging,self- discharging,etc..Results The BMS based on this method can attain an accurate surplus capa- city whose error is less than 5% in static experiments.It is proved by experiments that the BMS is reliable and can give the driver an accurate surplus capacity,precisely monitor the individual battery modules as the same time,even detect and warn the problems early,and so on. Conclusion A BMS can make the energy of the storage batteries used efficiently, develop the batteries cycle life,and increase the driving distance of EVs.展开更多
Aim To study the diesel engine management spstem (DEMS). The DEMS can consider many engine parameters and so it can acquire the optimum system performance. Methods On the basis of analyzing the characteristics of die...Aim To study the diesel engine management spstem (DEMS). The DEMS can consider many engine parameters and so it can acquire the optimum system performance. Methods On the basis of analyzing the characteristics of diesel engine electronic system, the real-time, multi-tasks system design methods were used for the heavy duty vehicular diesel engine electronic control system . The hardware and software of DEMS were developed. Results and Conalusion By the test on dieSel engine bed, the system was verified and the foundation of the fully developed DEMS was laid.展开更多
To facilitate system integration and evolution, modeling of complex systems requires a complementary management of system requirements and the architecture. Software tools are essential to support the above management...To facilitate system integration and evolution, modeling of complex systems requires a complementary management of system requirements and the architecture. Software tools are essential to support the above management effectively. The envisaged analysis tool for requirement and architecture management （ATRAM） is used to address the following 3 issues： （1） system requirements; （2） architecture presentation （modeling）; （3） representation （marking-up） and traceability between the components of both sides. In ATRAM, a set of analysis tools is proposed. It includes a tool assisting in the generation/development of requirement documents pertaining to the architecture of composed systems, and an XML based tool for interoperability checking. It is useful for analyzing the influences of the change on enterprise system requirements or the architecture.展开更多
In the Engine CAD application system engineering database management system (ECAD-EDBMS) is the kernel. ECAD-EDBMS can manage and process the multimedia such as graphics, data, text, sound, image and video. It provide...In the Engine CAD application system engineering database management system (ECAD-EDBMS) is the kernel. ECAD-EDBMS can manage and process the multimedia such as graphics, data, text, sound, image and video. It provides the integrated environment and more functions for many subsystems of ECAD and engine designers. So it improves the design efficiency.展开更多
How to construct integrative information management system for radiation oncology is a new practice in China based on new technical framework and the profile of integrating the healthcare enterprise in radiation oncol...How to construct integrative information management system for radiation oncology is a new practice in China based on new technical framework and the profile of integrating the healthcare enterprise in radiation oncology （IHE-RO）. This paper presents the research progress for constructing the system in the department of the radiation oncology at Cancer Hospital of Chinese Academy of Medical Sciences, and its system diagram based on IHE-RO technical framework, digital imaging and communication in medicine with radiotherapy （DICOM RT） data flow standard, and emphasizes the importance of DICOM RT in constructing the system and describes the generation process of DICOM RT objects. Finally, the related international standards are suggested on RT devices adopted by China State Food and Drug Administration （SFDA） when the system is constructed.展开更多
Related to complexity, there is a wide diversity of concepts, ranging from ‘‘systemic" to ‘‘complex", implying a need for a unified terminology. Per different authors, the main drivers of complexity can ...Related to complexity, there is a wide diversity of concepts, ranging from ‘‘systemic" to ‘‘complex", implying a need for a unified terminology. Per different authors, the main drivers of complexity can be found in human behaviour and uncertainty. This complexity, structural or dynamic can be organizational, technological, or nested in their relationship. ISO international standard 31000:2009 definition of risk management ‘‘coordinated activities to direct and control an organization with regard to risk", when applied to economic sectors, industry, services, project, or activity, it requires the use of models or theories as guidelines. Therefore, as its basic elements comprehend human behaviour and/or uncertainty, risk management to be effective and adapted as much as possible to reality, must be operational within complex systems, as already demonstrated in different R&D environments. Risk management faces demanding challenges when approaching specific and endogenous needs, such as the mining sector. This paper presents a multivariable function analysis methodology approach based on complex system modelling and through real data corresponding to a risk management tool in the mining sector.展开更多
The air traffic management system(ATM)has the task of ensuring safe,orderly and expeditious flow of air traffic.The ATM system architecture is very much dependent on the concept of operations(ConOps).Over the years th...The air traffic management system(ATM)has the task of ensuring safe,orderly and expeditious flow of air traffic.The ATM system architecture is very much dependent on the concept of operations(ConOps).Over the years the evolution in ConOps has resulted in changes in the ATM′s physical architecture,improving its physical infrastructure,increasing the levels of automation and making operational changes to improve air traffic flow,to cope with increasing demand for air travel.However,what is less clear is the impact of such changes in ConOps on the ATM′s functional architecture.This is vital for ensuring optimality in the implementation of the physical architecture components to support the ATM functions.This paper reviews the changes in the ConOps over the years,proposes a temporally invariant ATM functional model,and discusses some of the main key technologies expected to make significant improvements to the ATM system.展开更多
基金supported by NSFC project(grant No.61971359)Chongqing Municipal Key Laboratory of Institutions of Higher Education(grant No.cquptmct-202104)+1 种基金Fundamental Research Funds for the Central Universities,Sichuan Science and Technology Project(grant no.2021YFQ0053)State Key Laboratory of Rail Transit Engineering Informatization(FSDI).
文摘The increasing demand for industrial automation and intelligence has put forward higher requirements for the reliability of industrial wireless communication technology.As an international standard based on 802.11,Wireless networks for Industrial Automation-Factory Automation(WIA-FA)greatly improves the reliability in factory automation scenarios by Time Division Multiple Access(TDMA).However,in ultra-dense WIA-FA networks with mobile users,the basic connection management mechanism is inefficient.Most of the handover and resource management algorithms are all based on frequency division multiplexing,not suitable for the TDMA in the WIA-FA network.Therefore,we propose Load-aware Connection Management(LACM)algorithm to adjust the linkage and balance the load of access devices to avoid blocking and improve the reliability of the system.And then we simulate the algorithm to find the optimal settings of the parameters.After comparing with other existing algorithms,the result of the simulation proves that LACM is more efficient in reliability and maintains high reliability of more than 99.8%even in the ultra-dense moving scenario with 1500 field devices.Besides,this algorithm ensures that only a few signaling exchanges are required to ensure load bal-ancing,which is no more than 5 times,and less than half of the best state-of-the-art algorithm.
基金supported by the National Natural Science Foundation of China (No.62373224,62333013,and U23A20327)。
文摘With the increasing attention paid to battery technology,the microscopic reaction mechanism and macroscopic heat transfer process of lithium-ion batteries have been further studied and understood from both academic and industrial perspectives.Temperature,as one of the key parameters in the physical fra mework of batteries,affects the performa nce of the multi-physical fields within the battery,a nd its effective control is crucial.Since the heat generation in the battery is determined by the real-time operating conditions,the battery temperature is essentially controlled by the real-time heat dissipation conditions provided by the battery thermal management system.Conventional battery thermal management systems have basic temperature control capabilities for most conventional application scenarios.However,with the current development of la rge-scale,integrated,and intelligent battery technology,the adva ncement of battery thermal management technology will pay more attention to the effective control of battery temperature under sophisticated situations,such as high power and widely varied operating conditions.In this context,this paper presents the latest advances and representative research related to battery thermal management system.Firstly,starting from battery thermal profile,the mechanism of battery heat generation is discussed in detail.Secondly,the static characteristics of the traditional battery thermal management system are summarized.Then,considering the dynamic requirements of battery heat dissipation under complex operating conditions,the concept of adaptive battery thermal management system is proposed based on specific research cases.Finally,the main challenges for battery thermal management system in practice are identified,and potential future developments to overcome these challenges are presented and discussed.
基金funded by the National Key R&D Program of China(Grant No.2022YFD2200500)the Forestry Public Welfare Scientific Research Project(Grant No.201504303)。
文摘Climate change and forest management are recognized as pivotal factors influencing forest ecosystem services and thus multifunctionality.However,the magnitude and the relative importance of climate change and forest management effects on the multifunctionality remain unclear,especially for natural mixed forests.In this study,our objective is to address this gap by utilizing simulations of climate-sensitive transition matrix growth models based on national forest inventory plot data.We evaluated the effects of seven management scenarios(combinations of various cutting methods and intensities)on the future provision of ecosystem services and multifunctionality in mixed conifer-broad-leaved forests in northeastern China,under four climate scenarios(SSP1-2.6,SSP2-4.5,SSP5-8.5,and constant climate).Provisioning,regulating,cultural,and supporting services were described by timber production,carbon storage,carbon sequestration,tree species diversity,deadwood volume,and the number of large living trees.Our findings indicated that timber production was significantly influenced by management scenarios,while tree species diversity,deadwood volume,and large living trees were impacted by both climate and management separately.Carbon storage and sequestration were notably influenced by both management and the interaction of climate and management.These findings emphasized the profound impact of forest management on ecosystem services,outweighing that of climate scenarios alone.We found no single management scenario maximized all six ecosystem service indicators.The upper story thinning by 5%intensity with 5-year interval(UST5)management strategy emerged with the highest multifunctionality,surpassing the lowest values by more than 20%across all climate scenarios.In conclusion,our results underlined the potential of climate-sensitive transition matrix growth models as a decision support tool and provided recommendations for long-term strategies for multifunctional forest management under future climate change context.Ecosystem services and multifunctionality of forests could be enhanced by implementing appropriate management measures amidst a changing climate.
基金the funding and generous support of the National Natural Science Foundation of China(52103263,52271249)the Key Project of International Science&Technology Cooperation of Shaanxi Province(2023-GHZD-09)+5 种基金the Key Project of Science Foundation of Education Department of Shaanxi Province(22JY011)the Key Project of Scientific Research and Development of Shaanxi Province(2023GXLH-070)the Qinchuangyuan"Scientist+Engineer"Team of Shaanxi Province(2023KXJ-069)the Key Research and Development Program of Shaanxi(2023-YBGY-488)the Sci-tech Innovation Team of Shaanxi Province(2024RS-CXTD-46)the Key Research and Development Program of Shaanxi Province(2020ZDLGY13-11).
文摘All-season thermal management with zero energy consumption and emissions is more crucial to global decarbonization over traditional energy-intensive cooling/heating systems.However,the static single thermal management for cooling or heating fails to self-regulate the temperature in dynamic seasonal temperature condition.Herein,inspired by the dual-temperature regulation function of the fur color changes on the backs and abdomens of penguins,a smart thermal management composite hydrogel(PNA@H-PM Gel)system was subtly created though an"on-demand"dual-layer structure design strategy.The PNA@H-PM Gel system features synchronous solar and thermal radiation modulation as well as tunable phase transition temperatures to meet the variable seasonal thermal requirements and energy-saving demands via self-adaptive radiative cooling and solar heating regulation.Furthermore,this system demonstrates superb modulations of both the solar reflectance(ΔR=0.74)and thermal emissivity(ΔE=0.52)in response to ambient temperature changes,highlighting efficient temperature regulation with average radiative cooling and solar heating effects of 9.6℃in summer and 6.1℃in winter,respectively.Moreover,compared to standard building baselines,the PNA@H-PM Gel presents a more substantial energy-saving cooling/heating potentials for energy-efficient buildings across various regions and climates.This novel solution,inspired by penguins in the real world,will offer a fresh approach for producing intelligent,energy-saving thermal management materials,and serve for temperature regulation under dynamic climate conditions and even throughout all seasons.
基金supported by National Key Research and Development Program of China(Grant No.2024YFA1210500)National Natural Science Foundation of China(Grant Nos.U2341225 and 62375242)+1 种基金Sichuan Science and Technology Program(2025YFHZ0297)Postdoctoral Fellowship Program of CPSF(Grant No.GZB20240647).
文摘High-temperature stealth is vital for enhancing the concealment,survivability,and longevity of critical assets.However,achieving stealth across multiple infrared bands—particularly in the short-wave infrared(SWIR)band—along with microwave stealth and efficient thermal management at high temperatures,remains a significant challenge.Here,we propose a strategy that integrates an IR-selective emitter(Mo/Si multilayer films)and a microwave metasurface(TiB2–Al2O3–TiB2)to enable multi-infrared band stealth,encompassing mid-wave infrared(MWIR),long-wave infrared(LWIR),and SWIR bands,and microwave(X-band)stealth at 700℃,with simultaneous radiative cooling in non-atmospheric window(5–8μm).At 700℃,the device exhibits low emissivity of 0.38/0.44/0.60 in the MWIR/LWIR/SWIR bands,reflection loss below−3 dB in the X-band(9.6–12 GHz),and high emissivity of 0.82 in 5–8μm range—corresponding to a cooling power of 9.57 kW m^(−2).Moreover,under an input power of 17.3 kW m^(−2)—equivalent to the aerodynamic heating at Mach 2.2—the device demonstrates a temperature reduction of 72.4℃ compared to a conventional low-emissivity molybdenum surface at high temperatures.This work provides comprehensive guidance on high-temperature stealth design,with far-reaching implications for multispectral information processing and thermal management in extreme high-temperature environments.
基金Collaborative Innovation University Project of Anhui Province (GXXT-2022-018)National Natural Science Foundation of China (52374238 and 52074253)+3 种基金Natural Science Foundation of Anhui Province (2108085J28)Taishan Industrial Leading Talent Project (2019TSCYCX-27)Major Science and Technology Projects of Anhui Province(202103a05020011)Youth Innovation Promotion Association(CX2320007001)。
文摘Thermal management system is highly desirable to guarantee the performance and thermal safety of lithium-ion batteries,but it reduces the energy density of battery modules and even is unable to provide highly effective protection.Here,a thermal management function integrated material is presented based on high-temperature resistant aerogel and phase change material and is applied at both charge–discharge process and thermal runaway condition.In this sandwich structure Paraffin@SiC nanowire/Aerogel sheet (denoted as PA@SAS) system,SiC nanowires endow the middle aerogel sheet (SAS) a dual nano-network structure.The enhanced mechanical properties of SAS were studied by compressive tests and dynamic mechanical analysis.Besides,the thermal conductivity of SAS at 600°C is only 0.042 W/(m K).The surface phase change material layers facilitate temperature uniformity of batteries (surface temperature difference less than 1.82°C) through latent heat.Moreover,a large-format battery module with four 58 Ah LiNi0.5Co0.2Mn0.3O2LIBs was assembled.PA@SAS successfully prevents thermal runaway propagation,yielding a temperature gap of 602°C through the 2 mm-thick cross section.PA@SAS also exhibits excellent performance in other safety issues such as temperature rise rate,flame heat flux,etc.The lightweight property and effective insulation performance achieves significant safety enhancement with mass and volume energy density reduction of only 0.79%and 5.4%,respectively.The originality of the present research stems from the micro and macro structure design of the proposed thermal management material and the combination of intrinsic advantages of every component.This work provides a reliable design of achieving the integration of thermal management functions into an aerogel composite and improves the thermal safety of lithium-ion batteries.
基金financially supported by the National Natural Science Foundation of China(32192435)the Application and Demonstration Project of Network Security and Informatization Technology,Chinese Academy of Sciences(CAS-WX2022SF-0101)+1 种基金the Liaoning Provincial Key Research and Development Program(2023021230-JH2/1018)the Youth Innovation Promotion Association of CAS(2023205).
文摘Climate change is the most severe ecological challenge faced by the world today.Forests,the dominant component of terrestrial ecosystems,play a critical role in mitigating climate change due to their powerful carbon sequestration capabilities.Meanwhile,climate change has also become a major factor affecting the sustainable management of forest ecosystems.Climate-Smart Forestry(CSF)is an emerging concept in sustainable forest management.By utilizing advanced technologies,such as information technology and artificial intelligence,CSF aims to develop innovative and proactive forest management methods and decision-making systems to address the challenges of climate change.CSF aims to enhance forest ecosystem resilience(i.e.,maintain a condition where,even when the state of the ecosystem changes,the ecosystem functions do not deteriorate)through climate change adaptation,improve the mitigation capabilities of forest ecosystems to climate change,maintain high,stable,and sustainable forest productivity and ecosystem services,and ultimately achieve harmonious development between humans and nature.This concept paper:(1)discusses the emergence and development of CSF,which integrates Ecological Forestry,Carbon Forestry,and Smart Forestry,and proposes the concept of CSF;(2)analyzes the goals of CSF in improving forest ecosystem stability,enhancing forest ecosystem carbon sequestration capacity,and advocating the application and development of new technologies in CSF,including artificial intelligence,robotics,Light Detection and Ranging,and forest digital twin;(3)presents the latest practices of CSF based on prior research on forest structure and function using new generation information technologies at Qingyuan Forest,China.From these practices and reflections,we suggested the development direction of CSF,including the key research topics and technological advancement.
基金supported by Faculty of MedicineChiang Mai University+2 种基金supported by the National Center for Advancing Translational SciencesNational Institutes of Healththrough grant number UL1 TR001860. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH。
文摘BACKGROUND: Targeted temperature management(TTM) is a common therapeutic intervention, yet its cost-effectiveness remains uncertain. This study aimed to evaluate the real-world cost-effectiveness of TTM compared with that of conventional care in adult out-of-hospital cardiac arrest(OHCA) survivors using clinical patient-level data.METHODS: We conducted a retrospective cohort study at an academic medical center in the USA to assess the cost-effectiveness of TTM in adult non-traumatic OHCA survivors between 1 January, 2019 and 30 June, 2023. The primary outcome was survival to hospital discharge. Incremental cost-effectiveness ratios(ICERs) were calculated and compared with various decision makers' willingness to pay. Cost-effectiveness acceptability curves were utilized to evaluate the economic attractiveness of TTM. Uncertainty about the incremental cost and effect was explored with a 95% confidence ellipse.RESULTS: Among 925 non-traumatic OHCA survivors, only 30(3%) received TTM. After adjusting for potential confounders, the TTM group did not demonstrate a significantly lower cost(delta cost-$5,141, 95% confidence interval [95% CI]: $-35,347 to $25,065, P=0.79) and higher survival to hospital discharge(delta effect 6%, 95% CI:-11% to 23%, P=0.41). Additionally, a 95% confidence ellipse indicated uncertainty reflected by evidence that the true value of the ICER could be in any of the quadrants of the cost-effectiveness plane.CONCLUSION: Although TTM did not demonstrate a clear survival benefit in this study, its potential cost-effectiveness warrants further investigation with larger sample sizes. These findings highlight the need for additional research to optimize TTM use in OHCA care and inform resource allocation decisions.
基金financially supported by Heilongjiang Postdoctoral Fund(Grant No.LBH-Z24057)Outstanding Master’s and Doctoral Thesis of Longjiang in the New Era(Grant No.LJYXL2023-076).
文摘Radiative cooling fabric creates a thermally comfortable environment without energy input,providing a sustainable approach to personal thermal management.However,most currently reported fabrics mainly focus on outdoor cooling,ignoring to achieve simultaneous cooling both indoors and outdoors,thereby weakening the overall cooling performance.Herein,a full-scale structure fabric with selective emission properties is constructed for simultaneous indoor and outdoor cooling.The fabric achieves 94%reflectance performance in the sunlight band(0.3–2.5μm)and 6%in the mid-infrared band(2.5–25μm),effectively minimizing heat absorption and radiation release obstruction.It also demonstrates 81%radiative emission performance in the atmospheric window band(8–13μm)and 25%radiative transmission performance in the mid-infrared band(2.5–25μm),providing 60 and 26 W m−2 net cooling power outdoors and indoors.In practical applications,the fabric achieves excellent indoor and outdoor human cooling,with temperatures 1.4–5.5℃ lower than typical polydimethylsiloxane film.This work proposes a novel design for the advanced radiative cooling fabric,offering significant potential to realize sustainable personal thermal management.
基金part of the project“Areas of Forest Innovation Climate Smart Forestry”(project nr.101726),WP Modelling Plenter Forest vs.Even-aged Forest,funded by the Austrian Ministry of Agriculture,Forestry,Regions and Water Managementfunded by the province of Styria(Austria),the Austrian Federal Ministry of Agriculture,Forestry,Regions and Water Management and the European Union via the projects“Waldtypisierung Steiermark-FORSITE”(LE14-20)and“FORSITEⅡ-Investigation of the ecological base line information for a dynamic forest site classification in Upper Austria,Lower Austria and Burgenland”(101746)financial support came from BOKU University。
文摘Plenter forests,also known as uneven-aged or continuous cover forests enhance forest resilience and resistance against disturbances compared to even-aged forests.They are considered as an adaptation option to mitigate climate change effects.In this study,we present a conceptual approach to determine the potentially suitable area for plenter forest management within central European mixed species forests and apply our approach to the case study area in Styria,the south-eastern Province of Austria.The concept is based on ecological and technicaleconomic constraints and considers expected future climate conditions and its impact on plenter forest management.For each 1 ha forest pixel,we assess the ecological conditions for plenter forest management according to the autecological growth conditions of silver fir,and at least one additional shade tolerant tree species.The technical-economic constraints are defined by slope(≤30%)and distance to the next forest road(≤100 m)to ensure cost-efficient harvesting.The results show that under current climate conditions 28.1%or 305,349 ha of the forests in Styria are potentially suitable for plenter forest management.For the years 2071–2100 and under the climate change scenario RCP 4.5,the potential area decreases to 286,098 ha(26.3%of the total forest area)and for the scenario RCP 8.5 to 208,421 ha(19.1%of the total forest area).The main reason for these changes is the unfavourable growing conditions for silver fir in the lowlands,while in the higher elevations silver fir is likely to expand.Our results may serve forest managers to identify areas suitable for plenter forests and assist in the transformation of even-aged pure forests to uneven-aged forests to increase resistance,resilience,and biodiversity under climate change.
基金supported in part by the National Natural Science Foundation of China under Grant 61941113,Grant 61971033,and Grant 61671057by the Henan Provincial Department of Science and Technology Project(No.212102210408)by the Henan Provincial Key Scientific Research Project(No.22A520041).
文摘5G technology has endowed mobile communication terminals with features such as ultrawideband access,low latency,and high reliability transmission,which can complete the network access and interconnection of a large number of devices,thus realizing richer application scenarios and constructing 5G-enabled vehicular networks.However,due to the vulnerability of wireless communication,vehicle privacy and communication security have become the key problems to be solved in vehicular networks.Moreover,the large-scale communication in the vehicular networks also makes the higher communication efficiency an inevitable requirement.In order to achieve efficient and secure communication while protecting vehicle privacy,this paper proposes a lightweight key agreement and key update scheme for 5G vehicular networks based on blockchain.Firstly,the key agreement is accomplished using certificateless public key cryptography,and based on the aggregate signature and the cooperation between the vehicle and the trusted authority,an efficient key updating method is proposed,which reduces the overhead and protects the privacy of the vehicle while ensuring the communication security.Secondly,by introducing blockchain and using smart contracts to load the vehicle public key table for key management,this meets the requirements of vehicle traceability and can dynamically track and revoke misbehaving vehicles.Finally,the formal security proof under the eck security model and the informal security analysis is conducted,it turns out that our scheme is more secure than other authentication schemes in the vehicular networks.Performance analysis shows that our scheme has lower overhead than existing schemes in terms of communication and computation.
基金supported in part by the National Key R&D Program of China under Grant 2020YFB1806104in part by Innovation and Entrepreneurship of Jiangsu Province High-level Talent Program+1 种基金in part by Natural Sciences and Engineering Research Council of Canada (NSERC)the support from Huawei
文摘With the deployment of ultra-dense low earth orbit(LEO)satellite constellations,LEO satellite access network(LEO-SAN)is envisioned to achieve global Internet coverage.Meanwhile,the civil aviation communications have increased dramatically,especially for providing airborne Internet services.However,due to dynamic service demands and onboard LEO resources over time and space,it poses huge challenges in satellite-aircraft access and service management in ultra-dense LEO satellite networks(UDLSN).In this paper,we propose a deep reinforcement learning-based approach for ultra-dense LEO satellite-aircraft access and service management.Firstly,we develop an airborne Internet architecture based on UDLSN and design a management mechanism including medium earth orbit satellites to guarantee lightweight management.Secondly,considering latency-sensitive and latency-tolerant services,we formulate the problem of satellite-aircraft access and service management for civil aviation to ensure service continuity.Finally,we propose a proximal policy optimization-based access and service management algorithm to solve the formulated problem.Simulation results demonstrate the convergence and effectiveness of the proposed algorithm with satisfying the service continuity when applying to the UDLSN.
基金supported by Forschungsanstalt für Waldo kologie und Forstwirtschaft(FAWF)of Landesforsten Rheinland-Pfalz(FF 5.3-01-2021)。
文摘Forest ecosystems are important for biodiversity conservation and human societies,but are under pressure due to climate change and human interventions.This applies to natural forests as well as tree plantations.The latter are globally widespread and therefore gaining increasing importance for biodiversity conservation.However,even after dieback due to increasing disturbance frequencies,such plantations are primarily managed for economic returns,leading to growing conflicts among stakeholders.In particular,the impact of forest management on biodiversity is being discussed.This study investigates the effects of five management approaches in a landscape severely affected by spruce(Picea abies L.)dieback on beetle diversity,conservation,and community composition.We considered direct effects of management and indirect effects of environmental parameters separately in ground-dwelling and flight-active beetles.Beetle diversity was strongly affected by forest management,with nonintervention deadwood stands being most beneficial for beetles.In addition,we show indirect effects of environmental factors.In general,parameters related to salvage logging(e.g.open canopies,tree stumps)influenced beetle diversity and conservation negatively,while positive effects were found for soil nutrient availability and plant species richness.Community composition differed strongly among management categories and indicated a lack of landscape connectivity for open habitat species,as we found only low proportions of such species even on salvage-logged sites.We propose a mixture of management approaches after bark beetle outbreaks,including a substantial proportion of non-intervention deadwood stands,to increase landscape heterogeneity and connectivity.This may increase overall biodiversity while addressing the concerns of both forestry and species conservation.
文摘Aim To research and develop a battery management system(BMS)with the state of charge(SOC)indicator for electric vehicles (EVs).Methods On the basis of analyzing the electro-chemical characteristics of lead-acid. battery, the state of charge indicator for lead-acid battery was developed by means of an algorithm based on combination of ampere-hour, Peukert's equation and open-voltage method with the compensation of temperature,aging,self- discharging,etc..Results The BMS based on this method can attain an accurate surplus capa- city whose error is less than 5% in static experiments.It is proved by experiments that the BMS is reliable and can give the driver an accurate surplus capacity,precisely monitor the individual battery modules as the same time,even detect and warn the problems early,and so on. Conclusion A BMS can make the energy of the storage batteries used efficiently, develop the batteries cycle life,and increase the driving distance of EVs.
文摘Aim To study the diesel engine management spstem (DEMS). The DEMS can consider many engine parameters and so it can acquire the optimum system performance. Methods On the basis of analyzing the characteristics of diesel engine electronic system, the real-time, multi-tasks system design methods were used for the heavy duty vehicular diesel engine electronic control system . The hardware and software of DEMS were developed. Results and Conalusion By the test on dieSel engine bed, the system was verified and the foundation of the fully developed DEMS was laid.
文摘To facilitate system integration and evolution, modeling of complex systems requires a complementary management of system requirements and the architecture. Software tools are essential to support the above management effectively. The envisaged analysis tool for requirement and architecture management （ATRAM） is used to address the following 3 issues： （1） system requirements; （2） architecture presentation （modeling）; （3） representation （marking-up） and traceability between the components of both sides. In ATRAM, a set of analysis tools is proposed. It includes a tool assisting in the generation/development of requirement documents pertaining to the architecture of composed systems, and an XML based tool for interoperability checking. It is useful for analyzing the influences of the change on enterprise system requirements or the architecture.
文摘In the Engine CAD application system engineering database management system (ECAD-EDBMS) is the kernel. ECAD-EDBMS can manage and process the multimedia such as graphics, data, text, sound, image and video. It provides the integrated environment and more functions for many subsystems of ECAD and engine designers. So it improves the design efficiency.
基金Supported by the Foundation for the Cancer Hospital of Chinese Academy of Medical Sciences~~
文摘How to construct integrative information management system for radiation oncology is a new practice in China based on new technical framework and the profile of integrating the healthcare enterprise in radiation oncology （IHE-RO）. This paper presents the research progress for constructing the system in the department of the radiation oncology at Cancer Hospital of Chinese Academy of Medical Sciences, and its system diagram based on IHE-RO technical framework, digital imaging and communication in medicine with radiotherapy （DICOM RT） data flow standard, and emphasizes the importance of DICOM RT in constructing the system and describes the generation process of DICOM RT objects. Finally, the related international standards are suggested on RT devices adopted by China State Food and Drug Administration （SFDA） when the system is constructed.
文摘Related to complexity, there is a wide diversity of concepts, ranging from ‘‘systemic" to ‘‘complex", implying a need for a unified terminology. Per different authors, the main drivers of complexity can be found in human behaviour and uncertainty. This complexity, structural or dynamic can be organizational, technological, or nested in their relationship. ISO international standard 31000:2009 definition of risk management ‘‘coordinated activities to direct and control an organization with regard to risk", when applied to economic sectors, industry, services, project, or activity, it requires the use of models or theories as guidelines. Therefore, as its basic elements comprehend human behaviour and/or uncertainty, risk management to be effective and adapted as much as possible to reality, must be operational within complex systems, as already demonstrated in different R&D environments. Risk management faces demanding challenges when approaching specific and endogenous needs, such as the mining sector. This paper presents a multivariable function analysis methodology approach based on complex system modelling and through real data corresponding to a risk management tool in the mining sector.
文摘The air traffic management system(ATM)has the task of ensuring safe,orderly and expeditious flow of air traffic.The ATM system architecture is very much dependent on the concept of operations(ConOps).Over the years the evolution in ConOps has resulted in changes in the ATM′s physical architecture,improving its physical infrastructure,increasing the levels of automation and making operational changes to improve air traffic flow,to cope with increasing demand for air travel.However,what is less clear is the impact of such changes in ConOps on the ATM′s functional architecture.This is vital for ensuring optimality in the implementation of the physical architecture components to support the ATM functions.This paper reviews the changes in the ConOps over the years,proposes a temporally invariant ATM functional model,and discusses some of the main key technologies expected to make significant improvements to the ATM system.
