The acceleration and mode transition performance are two significant performances of Adaptive Cycle Engine(ACE).However,separating the processes of acceleration and mode transition will slow down the response speed of...The acceleration and mode transition performance are two significant performances of Adaptive Cycle Engine(ACE).However,separating the processes of acceleration and mode transition will slow down the response speed of thrust.Therefore,this paper proposes a multi-mode acceleration optimization control method that simultaneously performs ACE acceleration and mode transition.Firstly,an ACE component model with inlet flow characteristics was established,and the performance before and after mode transition were analyzed.Secondly,the principle of ACE acceleration optimization was analyzed,and the Front Variable Area Bypass Injector(FVABI)and Mode Selection Valve(MSV)were adopted in the acceleration process.Finally,based on the Sequential Quadratic Programming(SQP)algorithm,considering the degradation effects of engine components,we optimize the acceleration control plan for fuel and variable geometry mechanisms.The simulation results show that at the subsonic cruise point,the ACE multi-mode acceleration optimization control method can shorten the acceleration time from idle to middle state by 30.33%,and accelerate the thrust response speed by 33.72%.When the compressor flow rate of ACE deteriorates by 2% and the high-pressure turbine efficiency deteriorates by 4%,the adaptive acceleration control plan increases the high-pressure speed by 2.13% and thrust by about 6.82%;within the flight envelope,the acceleration time is reduced by more than 25%,and the thrust response speed is increased by more than 20%.展开更多
As a novel aero-engine concept,adaptive cycle aero-engines（ACEs） are attracting wide attention in the international aviation industry due to their potential superior task adaptability along a wide flight regime.Howe...As a novel aero-engine concept,adaptive cycle aero-engines（ACEs） are attracting wide attention in the international aviation industry due to their potential superior task adaptability along a wide flight regime.However,this superior task adaptability can only be demonstrated through proper combined engine control schedule design.It has resulted in an urgent need to investigate the effect of each variable geometry modulation on engine performance and stability.Thus,the aim of this paper is to predict and discuss the effect of each variable geometry modulation on the matching relationship between engine components as well as the overall engine performance at different operating modes,on the basis of a newly developed nonlinear component-based ACE performance model.Results show that at all four working modes,turning down the high pressure compressor variable stator vane,the low pressure turbine variable nozzle,the nozzle throat area,and turning up the core-driven fan stage variable stator vane,the high pressure turbine variable nozzle can increase the thrust at the expense of a higher high pressure turbine inlet total temperature.However,the influences of these adjustments on the trends of various engine components＇ working points and working lines as well as the ratio of the rotation speed difference are different from each other.The above results provide valuable guidance and advice for engine combined control schedule design.展开更多
Front Variable Area Bypass Injector(Front-VABI) is a component of the Adaptive Cycle Engine(ACE) with important variable-cycle features. The performance of Front-VABI has a direct impact on the performance and stabili...Front Variable Area Bypass Injector(Front-VABI) is a component of the Adaptive Cycle Engine(ACE) with important variable-cycle features. The performance of Front-VABI has a direct impact on the performance and stability of ACE, but the current ACE performance model uses approximate models for Front-VABI performance calculation. In this work, a multi-fidelity simulation based on a de-coupled method is developed which delivers a more accurate calculation of the Front-VABI performance based on Computational Fluid Dynamics(CFD) simulation. This simulation method proposes a form of Front-VABI characteristic and its matching calculation method between it and the ACE performance model, constructs a coupling method between the(2-D) Front-VABI model and the(0-D) ACE performance model. The result shows, when ACE works in triple bypass mode, the approximate model cannot account for the effect of FrontVABI pressure loss on Core Driven Fan Stage(CDFS) design pressure ratio, and the calculated error of high-pressure turbine inlet total temperature is more than 40 K in mode transition condition(the transition operating condition between triple bypass mode and double bypass mode). In double bypass mode, the approximate model can better simulate the performance of FrontVABI by considering the local loss of area expansion. This method can be applied to the performance-optimized design of Front-VABI and the ACE control law design during mode transition.展开更多
The alternative working modes and flexible working states are the outstanding features of an adaptive cycle engine, with a proper control schedule design being the only way to exploit the performance of such an engine...The alternative working modes and flexible working states are the outstanding features of an adaptive cycle engine, with a proper control schedule design being the only way to exploit the performance of such an engine. However, unreasonable design in the control schedule causes not only performance deterioration but also serious aerodynamic stability problems. Thus, in this work,a hybrid optimization method that automatically chooses the working modes and identifies the optimal and smooth control schedules is proposed, by combining the differential evolution algorithm and the Latin hypercube sampling method. The control schedule architecture does not only optimize the engine steady-state performance under different working modes but also solves the control-schedule discontinuity problem, especially during mode transition. The optimal control schedules are continuous and almost monotonic, and hence are strongly suitable for a control system, and are designed for two different working conditions, i.e., supersonic and subsonic throttling,which proves that the proposed hybrid method applies to various working conditions. The evaluation demonstrates that the proposed control method optimizes the engine performance, the surge margin of the compression components, and the range of the thrust during throttling.展开更多
To design the optimum acceleration control schedule for the Adaptive Cycle Engine(ACE)in the full flight envelope,this paper establishes a direct simulation model of the ACE transient state.In this model,geometric par...To design the optimum acceleration control schedule for the Adaptive Cycle Engine(ACE)in the full flight envelope,this paper establishes a direct simulation model of the ACE transient state.In this model,geometric parameters are used to replace the component state parameters.The corresponding relationship between geometric parameters and component state parameters is determined by sensitivity analysis.The geometric variables are controlled when the geometric adjustment speed exceeds the limit,and at the same time the corresponding component state parameters are iterated.The gradient optimization algorism is used to optimize the ground acceleration process of ACE,and the control schedule in terms of operating point of compression components and corrected acceleration rate is used as the full-envelope acceleration control schedule based on the similarity principle.The acceleration control schedules of the triple-bypass mode and the double-bypass mode are designed in this paper.The acceleration processes under various flight conditions are simulated using the acceleration control schedules.Compared with the acceleration process with the linear geometric adjustment schedule,the acceleration performance of ACE is improved by the acceleration control schedule,with the impulse of the acceleration process of the triple-bypass mode being increased by 8.7%-12.3% and the impulse of the double-bypass mode acceleration process being increased by 11.8%-14.1%.展开更多
The adaptive cycle engine(ACE)is considered a crucial candidate for the propulsion systems of next-generation aircraft.Its high thrust and low fuel consumption operating modes make it suitable for various flight missi...The adaptive cycle engine(ACE)is considered a crucial candidate for the propulsion systems of next-generation aircraft.Its high thrust and low fuel consumption operating modes make it suitable for various flight missions.However,the complex couplings and novel components in the ACE pose significant challenges to its performance design.This paper presents a systematic literature review on development status and performance deign of ACEs.Firstly,the development of ACE at various periods over the past few decades is presented.Then,four typical ACE configurations are introduced and analyzed based the differences of the core and the low-pressure compression system.After that,an emphasis is placed on the performance optimization method for ACE under various operating conditions,including steadystate,mode transition,acceleration/deceleration,and considering uncertainties.In addition,the numerical zooming technology for non-rotating components,rotating components,as well as intake and exhaust system are summarized in this paper.Through the above summary and analysis,the development trends in ACE performance design are explored.展开更多
The spatial form of historic blocks comprises multi-scale elements,and its evolutionary process is the result of residents'long-term adaptation to and coexistence with the external environment.This micro-level,dyn...The spatial form of historic blocks comprises multi-scale elements,and its evolutionary process is the result of residents'long-term adaptation to and coexistence with the external environment.This micro-level,dynamic,and complex system requires an interpretation grounded in theoretical frameworks that align more closely with real-world logic.This paper integrates Conzenian urban morphology,the adaptive cycle theory of social-ecological systems,and the complex adaptive system theory to develop a research framework for analyzing the morphological evolutionary characteristics,mechanisms,and pathways of historic blocks from a complex adaptive perspective.Taking the Hui-Fang area in Xi'an,a historic block,as an example,the paper employs quantitative methods,such as fractal dimension analysis and space syntax,to uncover both the complex external manifestations of the morphological system and the underlying adaptive cycle mechanisms of the agent system.Furthermore,it identifies three distinct adaptive evolutionary pathways of spatial form:unidirectional control,bidirectional guidance,and multi-level symbiosis.This research expands epistemological understandings of morphological evolution and provides theoretical support for the development of urban spaces in historic blocks that reflect regional cultural significance.展开更多
A segmented predictor-corrector method is proposed for hypersonic glide vehicles to address the issue of the slow computational speed of obtaining guidance commands using the traditional predictor-corrector guidance m...A segmented predictor-corrector method is proposed for hypersonic glide vehicles to address the issue of the slow computational speed of obtaining guidance commands using the traditional predictor-corrector guidance method.Firstly,an altitude-energy profile is designed,and the bank angle is derived analytically as the initial iteration value for the predictor-corrector method.The predictor-corrector guidance method has been improved by deriving an analytical form for predicting the range-to-go error,which greatly accelerates the iterative speed.Then,a segmented guidance algorithm is proposed.The above analytically predictor-corrector guidance method is adopted when the energy exceeds an energy threshold.When the energy is less than the threshold,the equidistant test method is used to calculate the bank angle command,which ensures guidance accuracy as well as computational efficiency.Additionally,an adaptive guidance cycle strategy is applied to reduce the computational time of the reentry guidance trajectory.Finally,the accuracy and robustness of the proposed method are verified through a series of simulations and Monte-Carlo experiments.Compared with the traditional integral method,the proposed method requires 75%less computation time on average and achieves a lower landing error.展开更多
Accurate engine performance models are important for model-based performance evaluation of aero engine.The accuracy of the model often depends on engine component maps,so there is a need for a method that can accurate...Accurate engine performance models are important for model-based performance evaluation of aero engine.The accuracy of the model often depends on engine component maps,so there is a need for a method that can accurately correct the component maps of the model over a wide range.In this paper,a new method for modifying component maps is proposed,this method combines the correction of the scaling factors with the solution process of the off-design working point,and uses the adjustment of the variable geometric parameters of the engine to change the position of the working line,in order to obtain more correction results and guarantee high accuracy in a wider range.The method is validated by taking the main fan of the Adaptive Cycle Engine(ACE),an ideal power unit for a new generation of multi-purpose and ultra-wide working range aircraft,as an example.The results show that the maximum error between the corrected component maps and the target maps is less than 1%.New possibility for more precise component maps can be realized in this paper.展开更多
Sustainable development is a holistic approach harmonizing ecological, economical and socio-political needs with respect to the superior objective of enhancing human living standards. Thereby the availability of natur...Sustainable development is a holistic approach harmonizing ecological, economical and socio-political needs with respect to the superior objective of enhancing human living standards. Thereby the availability of natural resources and the conservation of the ecosystems have to be considered that future generations have the possibility to meet their own needs. A long-term economical development demands the transition from a souree-sink economy to a cycle economy as a result of limited resources, limited environmental capacities to absorb waste and emissions as well as increasing needs of a growing population. A reference model for snstainability in manufacturing is presented and used to illustrate sustainable approaches with respect to management, technology, process and product. Adaptation of products and components is a vital element for supporting efficient reuse of products and components. Consequently adaptation contributes to the ambitions goals of snstainability. Technological enablers for adaptation as modularity, information and communication technology are exemplarily introduced. Moreover, approaches for disseminating knowledge in sustainability are given.展开更多
In an era marked by escalating climate change and urban vulnerability,enhancing the resilience of infrastructure and communities has become critical.Advanced monitoring technologies are vital for providing real-time d...In an era marked by escalating climate change and urban vulnerability,enhancing the resilience of infrastructure and communities has become critical.Advanced monitoring technologies are vital for providing real-time data to assess and strengthen resilience,enabling proactive risk management and sustainable development.In this paper,a real-time distributed acoustic sensing(DAS)system was deployed at Nanjing University Xianlin Campus,Nanjing,China,utilizing a 3.8-km-long underground fiber-optic cable array.Continuous data collection has been conducted since February 2023.The effectiveness of the monitoring system in dynamically assessing and strengthening campus resilience is investigated.By analyzing power spectral density fluctuations and spatiotemporal correlations in DAS data,this study captures variations in campus activity patterns across different functional zones and time periods.The results demonstrate that DAS can effectively monitor human and environmental dynamics in real-time,providing data-driven insights for optimizing traffic management,resource allocation,and facility operations.Furthermore,the integration of DAS with the adaptive cycle framework enhances campus resilience during exploitation,conservation,release,and reorganization stages.This work validates the potential of DAS as a powerful tool for building resilient and sustainable urban environments.Its cost-effectiveness and high-resolution monitoring capabilities make it a promising solution for future urban development and resilience planning.展开更多
Traditional rural social-ecological systems(SES)share many features which are crucial for sus-tainable development.Eastern European countries such as Romania,are still rich in traditional cultural landscapes.However,t...Traditional rural social-ecological systems(SES)share many features which are crucial for sus-tainable development.Eastern European countries such as Romania,are still rich in traditional cultural landscapes.However,these landscapes are increasingly under internal(e.g.,people’s aspirations toward western socioeconomic ideals)and external(institutional changes,globalization of the commodity market,connectivity with other cultures)pressures.Therefore,understanding the ways how traditional SES navi-gated past and more recent changes is of crucial importance in getting insights about the future trajectory of these systems.Here,we present the rural SES from the Saxon region of Transylvania through the lens of institutional transitions which happened in the past century in this region.We show that the rural SES went through episodic collapses and renewals,their cyclic dynamic being related to the episodic chang-es of the higher level formal institutions.These episodic collapses and renewals created a social-ecolog-ical momentum for the sustainability of these SES.While we recognize that policy effectiveness depends on institutional stability(and institutions are unstable and prone to collapses),maintaining those social-ecological system properties which can assure navigation of societies through the challenges imposed by global changes should be in the heart of every governance system.Such properties includes wide extent of native vegetation,fertile soils,wide range of provisioning ecosystem services,genuine links between people and landscapes and knowledge about the social-ecological systems.These features could provide important capitals and memory elements for the(re)emergence of social-ecological systems(old or new).展开更多
Urban water-related problems associated with rapid urbanization, including waterlogging, water pollution, the ecological degradation of water, and water shortages, have caused global concerns in recent years. In 2013,...Urban water-related problems associated with rapid urbanization, including waterlogging, water pollution, the ecological degradation of water, and water shortages, have caused global concerns in recent years. In 2013, in order to mitigate increasingly severe urban water-related problems, China set forth a new strategy for integrated urban water management(IUWM) called the "Sponge City". This is the first holistic IUWM strategy implemented in a developing country that is still undergoing rapid urbanization, and holds promise for application in other developing countries. This paper aims to comprehensively summarize the sponge city. First, this paper reviews prior studies and policies on urban water management in China as important background for the sponge city proposal. Then, the connotations, goals, and features of the sponge city are summarized and discussed.Finally, the challenges, research needs, and development directions pertinent to the sponge city are discussed based on investigations and studies conducted by the authors. The sponge city in China has a short history—given this, there are many issues that should be examined with regard to the stepwise implementation of the Sponge City Programme(SCP). Accordingly, the authors perceive this study as only the beginning of abundant studies on the sponge city.展开更多
基金supported in part by the National Natural Science Foundation of China(No.52372389)the Jiangsu Province Excellent Postdoctoral Program of China(No.2023ZB494)+1 种基金the Basic Research Program of Jiangsu Province,China(No.BK20241412)the National Science Foundation for Post-doctoral Scientists of China(No.2024M754131)。
文摘The acceleration and mode transition performance are two significant performances of Adaptive Cycle Engine(ACE).However,separating the processes of acceleration and mode transition will slow down the response speed of thrust.Therefore,this paper proposes a multi-mode acceleration optimization control method that simultaneously performs ACE acceleration and mode transition.Firstly,an ACE component model with inlet flow characteristics was established,and the performance before and after mode transition were analyzed.Secondly,the principle of ACE acceleration optimization was analyzed,and the Front Variable Area Bypass Injector(FVABI)and Mode Selection Valve(MSV)were adopted in the acceleration process.Finally,based on the Sequential Quadratic Programming(SQP)algorithm,considering the degradation effects of engine components,we optimize the acceleration control plan for fuel and variable geometry mechanisms.The simulation results show that at the subsonic cruise point,the ACE multi-mode acceleration optimization control method can shorten the acceleration time from idle to middle state by 30.33%,and accelerate the thrust response speed by 33.72%.When the compressor flow rate of ACE deteriorates by 2% and the high-pressure turbine efficiency deteriorates by 4%,the adaptive acceleration control plan increases the high-pressure speed by 2.13% and thrust by about 6.82%;within the flight envelope,the acceleration time is reduced by more than 25%,and the thrust response speed is increased by more than 20%.
基金supported by the National Natural Science Foundation of China(No.51206005)Collaborative Innovation Center of Advanced Aero-Engine of China
文摘As a novel aero-engine concept,adaptive cycle aero-engines（ACEs） are attracting wide attention in the international aviation industry due to their potential superior task adaptability along a wide flight regime.However,this superior task adaptability can only be demonstrated through proper combined engine control schedule design.It has resulted in an urgent need to investigate the effect of each variable geometry modulation on engine performance and stability.Thus,the aim of this paper is to predict and discuss the effect of each variable geometry modulation on the matching relationship between engine components as well as the overall engine performance at different operating modes,on the basis of a newly developed nonlinear component-based ACE performance model.Results show that at all four working modes,turning down the high pressure compressor variable stator vane,the low pressure turbine variable nozzle,the nozzle throat area,and turning up the core-driven fan stage variable stator vane,the high pressure turbine variable nozzle can increase the thrust at the expense of a higher high pressure turbine inlet total temperature.However,the influences of these adjustments on the trends of various engine components＇ working points and working lines as well as the ratio of the rotation speed difference are different from each other.The above results provide valuable guidance and advice for engine combined control schedule design.
基金funded by National Natural Science Foundation of China(Nos.51776010 and 91860205)National Science and Technology Major Project,China(No.2017-I0001-0001)。
文摘Front Variable Area Bypass Injector(Front-VABI) is a component of the Adaptive Cycle Engine(ACE) with important variable-cycle features. The performance of Front-VABI has a direct impact on the performance and stability of ACE, but the current ACE performance model uses approximate models for Front-VABI performance calculation. In this work, a multi-fidelity simulation based on a de-coupled method is developed which delivers a more accurate calculation of the Front-VABI performance based on Computational Fluid Dynamics(CFD) simulation. This simulation method proposes a form of Front-VABI characteristic and its matching calculation method between it and the ACE performance model, constructs a coupling method between the(2-D) Front-VABI model and the(0-D) ACE performance model. The result shows, when ACE works in triple bypass mode, the approximate model cannot account for the effect of FrontVABI pressure loss on Core Driven Fan Stage(CDFS) design pressure ratio, and the calculated error of high-pressure turbine inlet total temperature is more than 40 K in mode transition condition(the transition operating condition between triple bypass mode and double bypass mode). In double bypass mode, the approximate model can better simulate the performance of FrontVABI by considering the local loss of area expansion. This method can be applied to the performance-optimized design of Front-VABI and the ACE control law design during mode transition.
基金funded by National Nature Science Foundation of China(Nos.51776010 and 91860205)supported by the Academic Excellence Foundation of BUAA for PhD Students,China。
文摘The alternative working modes and flexible working states are the outstanding features of an adaptive cycle engine, with a proper control schedule design being the only way to exploit the performance of such an engine. However, unreasonable design in the control schedule causes not only performance deterioration but also serious aerodynamic stability problems. Thus, in this work,a hybrid optimization method that automatically chooses the working modes and identifies the optimal and smooth control schedules is proposed, by combining the differential evolution algorithm and the Latin hypercube sampling method. The control schedule architecture does not only optimize the engine steady-state performance under different working modes but also solves the control-schedule discontinuity problem, especially during mode transition. The optimal control schedules are continuous and almost monotonic, and hence are strongly suitable for a control system, and are designed for two different working conditions, i.e., supersonic and subsonic throttling,which proves that the proposed hybrid method applies to various working conditions. The evaluation demonstrates that the proposed control method optimizes the engine performance, the surge margin of the compression components, and the range of the thrust during throttling.
基金co-supported by the National Science and Technology Major Project,China(No.J2019-I-0015-0014)the National Natural Science Foundation of China(No.52372397).
文摘To design the optimum acceleration control schedule for the Adaptive Cycle Engine(ACE)in the full flight envelope,this paper establishes a direct simulation model of the ACE transient state.In this model,geometric parameters are used to replace the component state parameters.The corresponding relationship between geometric parameters and component state parameters is determined by sensitivity analysis.The geometric variables are controlled when the geometric adjustment speed exceeds the limit,and at the same time the corresponding component state parameters are iterated.The gradient optimization algorism is used to optimize the ground acceleration process of ACE,and the control schedule in terms of operating point of compression components and corrected acceleration rate is used as the full-envelope acceleration control schedule based on the similarity principle.The acceleration control schedules of the triple-bypass mode and the double-bypass mode are designed in this paper.The acceleration processes under various flight conditions are simulated using the acceleration control schedules.Compared with the acceleration process with the linear geometric adjustment schedule,the acceleration performance of ACE is improved by the acceleration control schedule,with the impulse of the acceleration process of the triple-bypass mode being increased by 8.7%-12.3% and the impulse of the double-bypass mode acceleration process being increased by 11.8%-14.1%.
基金funded by National Natural Science Foundation of China(NSFC)under Grants(No.51776010)the Fundamental Research Funds for the Central Universities and the Stable support project of the State Key Laboratory(No.12700002024146001).
文摘The adaptive cycle engine(ACE)is considered a crucial candidate for the propulsion systems of next-generation aircraft.Its high thrust and low fuel consumption operating modes make it suitable for various flight missions.However,the complex couplings and novel components in the ACE pose significant challenges to its performance design.This paper presents a systematic literature review on development status and performance deign of ACEs.Firstly,the development of ACE at various periods over the past few decades is presented.Then,four typical ACE configurations are introduced and analyzed based the differences of the core and the low-pressure compression system.After that,an emphasis is placed on the performance optimization method for ACE under various operating conditions,including steadystate,mode transition,acceleration/deceleration,and considering uncertainties.In addition,the numerical zooming technology for non-rotating components,rotating components,as well as intake and exhaust system are summarized in this paper.Through the above summary and analysis,the development trends in ACE performance design are explored.
基金supported by the General Program of the National Natural Science Foundation of China(No.52478070)the Humanities and Social Science General Program of the Ministry of Education(No.22YJC760134)。
文摘The spatial form of historic blocks comprises multi-scale elements,and its evolutionary process is the result of residents'long-term adaptation to and coexistence with the external environment.This micro-level,dynamic,and complex system requires an interpretation grounded in theoretical frameworks that align more closely with real-world logic.This paper integrates Conzenian urban morphology,the adaptive cycle theory of social-ecological systems,and the complex adaptive system theory to develop a research framework for analyzing the morphological evolutionary characteristics,mechanisms,and pathways of historic blocks from a complex adaptive perspective.Taking the Hui-Fang area in Xi'an,a historic block,as an example,the paper employs quantitative methods,such as fractal dimension analysis and space syntax,to uncover both the complex external manifestations of the morphological system and the underlying adaptive cycle mechanisms of the agent system.Furthermore,it identifies three distinct adaptive evolutionary pathways of spatial form:unidirectional control,bidirectional guidance,and multi-level symbiosis.This research expands epistemological understandings of morphological evolution and provides theoretical support for the development of urban spaces in historic blocks that reflect regional cultural significance.
基金National Natural Science Foundation of China(Nos.61773387 and 62022061).
文摘A segmented predictor-corrector method is proposed for hypersonic glide vehicles to address the issue of the slow computational speed of obtaining guidance commands using the traditional predictor-corrector guidance method.Firstly,an altitude-energy profile is designed,and the bank angle is derived analytically as the initial iteration value for the predictor-corrector method.The predictor-corrector guidance method has been improved by deriving an analytical form for predicting the range-to-go error,which greatly accelerates the iterative speed.Then,a segmented guidance algorithm is proposed.The above analytically predictor-corrector guidance method is adopted when the energy exceeds an energy threshold.When the energy is less than the threshold,the equidistant test method is used to calculate the bank angle command,which ensures guidance accuracy as well as computational efficiency.Additionally,an adaptive guidance cycle strategy is applied to reduce the computational time of the reentry guidance trajectory.Finally,the accuracy and robustness of the proposed method are verified through a series of simulations and Monte-Carlo experiments.Compared with the traditional integral method,the proposed method requires 75%less computation time on average and achieves a lower landing error.
基金funded by National Nature Science Foundation of China(NSFC)(Nos.51776010,and 91860205)the support from Collaborative Innovation Center of Advanced Aero-Engine,china。
文摘Accurate engine performance models are important for model-based performance evaluation of aero engine.The accuracy of the model often depends on engine component maps,so there is a need for a method that can accurately correct the component maps of the model over a wide range.In this paper,a new method for modifying component maps is proposed,this method combines the correction of the scaling factors with the solution process of the off-design working point,and uses the adjustment of the variable geometric parameters of the engine to change the position of the working line,in order to obtain more correction results and guarantee high accuracy in a wider range.The method is validated by taking the main fan of the Adaptive Cycle Engine(ACE),an ideal power unit for a new generation of multi-purpose and ultra-wide working range aircraft,as an example.The results show that the maximum error between the corrected component maps and the target maps is less than 1%.New possibility for more precise component maps can be realized in this paper.
文摘Sustainable development is a holistic approach harmonizing ecological, economical and socio-political needs with respect to the superior objective of enhancing human living standards. Thereby the availability of natural resources and the conservation of the ecosystems have to be considered that future generations have the possibility to meet their own needs. A long-term economical development demands the transition from a souree-sink economy to a cycle economy as a result of limited resources, limited environmental capacities to absorb waste and emissions as well as increasing needs of a growing population. A reference model for snstainability in manufacturing is presented and used to illustrate sustainable approaches with respect to management, technology, process and product. Adaptation of products and components is a vital element for supporting efficient reuse of products and components. Consequently adaptation contributes to the ambitions goals of snstainability. Technological enablers for adaptation as modularity, information and communication technology are exemplarily introduced. Moreover, approaches for disseminating knowledge in sustainability are given.
基金supported by the National Natural Science Foundation of China(Grant Nos.42225702,42407250)the Natural Science Foundation of Jiangsu Province(Grant No.BK20241211)。
文摘In an era marked by escalating climate change and urban vulnerability,enhancing the resilience of infrastructure and communities has become critical.Advanced monitoring technologies are vital for providing real-time data to assess and strengthen resilience,enabling proactive risk management and sustainable development.In this paper,a real-time distributed acoustic sensing(DAS)system was deployed at Nanjing University Xianlin Campus,Nanjing,China,utilizing a 3.8-km-long underground fiber-optic cable array.Continuous data collection has been conducted since February 2023.The effectiveness of the monitoring system in dynamically assessing and strengthening campus resilience is investigated.By analyzing power spectral density fluctuations and spatiotemporal correlations in DAS data,this study captures variations in campus activity patterns across different functional zones and time periods.The results demonstrate that DAS can effectively monitor human and environmental dynamics in real-time,providing data-driven insights for optimizing traffic management,resource allocation,and facility operations.Furthermore,the integration of DAS with the adaptive cycle framework enhances campus resilience during exploitation,conservation,release,and reorganization stages.This work validates the potential of DAS as a powerful tool for building resilient and sustainable urban environments.Its cost-effectiveness and high-resolution monitoring capabilities make it a promising solution for future urban development and resilience planning.
基金The publication of this manuscript was supported by the EEA Financial Mechanism and the Romanian Ministry of Environment,Forests and Waters under the project“Mapping and assessment of ecosystem services in Natura 2000 sites of the Niraj-Tarnava Mica region”(Programme RO02,grant No.3458/19.05.2015 to Milvus Group)through Bálint Czúcz.BC was supported also by the Bolyai scholarship of the Hungarian Academy of Sciences.
文摘Traditional rural social-ecological systems(SES)share many features which are crucial for sus-tainable development.Eastern European countries such as Romania,are still rich in traditional cultural landscapes.However,these landscapes are increasingly under internal(e.g.,people’s aspirations toward western socioeconomic ideals)and external(institutional changes,globalization of the commodity market,connectivity with other cultures)pressures.Therefore,understanding the ways how traditional SES navi-gated past and more recent changes is of crucial importance in getting insights about the future trajectory of these systems.Here,we present the rural SES from the Saxon region of Transylvania through the lens of institutional transitions which happened in the past century in this region.We show that the rural SES went through episodic collapses and renewals,their cyclic dynamic being related to the episodic chang-es of the higher level formal institutions.These episodic collapses and renewals created a social-ecolog-ical momentum for the sustainability of these SES.While we recognize that policy effectiveness depends on institutional stability(and institutions are unstable and prone to collapses),maintaining those social-ecological system properties which can assure navigation of societies through the challenges imposed by global changes should be in the heart of every governance system.Such properties includes wide extent of native vegetation,fertile soils,wide range of provisioning ecosystem services,genuine links between people and landscapes and knowledge about the social-ecological systems.These features could provide important capitals and memory elements for the(re)emergence of social-ecological systems(old or new).
基金supported by the National Key Research and Development Program of China(Grant No.2016YFC0401401)the National Natural Science Foundation of China(Grant Nos.51522907&51739011)supported by the Research Fund of the State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin,China Institute of Water Resources and Hydropower Research(Grant No.2017ZY02)
文摘Urban water-related problems associated with rapid urbanization, including waterlogging, water pollution, the ecological degradation of water, and water shortages, have caused global concerns in recent years. In 2013, in order to mitigate increasingly severe urban water-related problems, China set forth a new strategy for integrated urban water management(IUWM) called the "Sponge City". This is the first holistic IUWM strategy implemented in a developing country that is still undergoing rapid urbanization, and holds promise for application in other developing countries. This paper aims to comprehensively summarize the sponge city. First, this paper reviews prior studies and policies on urban water management in China as important background for the sponge city proposal. Then, the connotations, goals, and features of the sponge city are summarized and discussed.Finally, the challenges, research needs, and development directions pertinent to the sponge city are discussed based on investigations and studies conducted by the authors. The sponge city in China has a short history—given this, there are many issues that should be examined with regard to the stepwise implementation of the Sponge City Programme(SCP). Accordingly, the authors perceive this study as only the beginning of abundant studies on the sponge city.
