A new reliability allocation model has been built for engine system, which is a repairable system, and consists of a large number of mechanical components. The cost and reliability are taken as objective function and ...A new reliability allocation model has been built for engine system, which is a repairable system, and consists of a large number of mechanical components. The cost and reliability are taken as objective function and constraint condition respectively. The parameters of components lifetime distribution are given as decision variables, and the component lifetimes are assumed to follow that Weibull distribution. The allocation is separated into two steps to reduce calculated amount of one allocation. Genetic algorithm and Monte Carlo method are applied to solve distribution parameters and system cost separately.展开更多
The global demand for transport energy is large, growing, and primarily met by petroleum-derived liquid fuels powering internal combustion engines (ICEs). Moreover, the demand for jet fuel and diesel is projected to g...The global demand for transport energy is large, growing, and primarily met by petroleum-derived liquid fuels powering internal combustion engines (ICEs). Moreover, the demand for jet fuel and diesel is projected to grow faster than the demand for gasoline in the future, and is likely to result in low-octane gasoline components becoming more readily available. Significant initiatives with varying motivations are taking place to develop the battery electric vehicle (BEV) and the fuel cell as alternatives to ICE vehicles, and to establish fuels such as biofuels and natural gas as alternatives to conventional liquid fuels. However, each of these alternatives starts from a very low base and faces significant barriers to fast and unrestrained growth;thus, transport—and particularly commercial transport—will continue to be largely powered by ICEs running on petroleum-based liquid fuels for decades to come. Hence, the sustainability of transport in terms of affordability, energy security, and impact on greenhouse gas (GHG) emissions and air quality can only be ensured by improving ICEs. Indeed, ICEs will continue to improve while using current market fuels, through improvements in combustion, control, and after-treatment systems, assisted by partial electrification in the form of hybridization. However, there is even more scope for improvement through the development of fuel/engine systems that can additionally leverage benefits in fuels manufacture and use components that may be readily available. Gasoline compression ignition (GCI), which uses low-octane gasoline in a compression ignition engine, is one such example. GCI would enable diesel-like efficiencies while making it easier to control nitrogen oxides (NOx) and particulates at a lower cost compared with modern diesel engines. Octane on demand (OOD) also helps to ensure optimum use of available fuel anti-knock quality, and thus improves the overall efficiency of the system.展开更多
A new hybrid control scheme is presented with a robust multiple model fusion control（RMMFC） law for a UH-60 helicopter and an active disturbance rejection control（ADRC） controller for its engines.This scheme is a ...A new hybrid control scheme is presented with a robust multiple model fusion control（RMMFC） law for a UH-60 helicopter and an active disturbance rejection control（ADRC） controller for its engines.This scheme is a control design method with every subsystem designed separately but fully considering the couplings between them.With three subspaces with respect to forward flight velocity,a RMMFC is proposed to devise a four-loop reference signal tracing control for the helicopter,which escapes the closed-loop system from unstable state due to the extreme complexity of this integrated nonlinear system.The engines are controlled by the proposed ADRC decoupling controller,which fully takes advantage of a good compensation ability for unmodeled dynamics and extra disturbances,so as to compensate torque disturbance in power turbine speed loop.By simulating a forward acceleration flight task,the RMMFC for the helicopter is validated.It is apparent that the integrated helicopter and engine system（IHES） has much better dynamic performance under the new control scheme.Especially in the switching process,the large transient is significantly weakened,and smooth transition among candidate controllers is achieved.Over the entire simulation task,the droop of power turbine speed with the proposed ADRC controller is significantly slighter than with the conventional PID controller,and the response time of the former is much faster than the latter.By simulating a rapid climb and descent flight task,the results also show the feasibility for the application of the proposed multiple model fusion control.Although there is aggressive power demand in this maneuver,the droop of power turbine speed with an ADRC controller is smaller than using a PID controller.The control performance for helicopter and engine is enhanced by adopting this hybrid control scheme,and simulation results in other envelope state give proofs of robustness for this new scheme.展开更多
This article corrects the following:Volume 2 Issue 4 Journal of Dynamics,Monitoring and Diagnostics Inter-shaft Bearing Fault Diagnosis Based on Aero-engine System:A Benchmarking Dataset Study Pages:228-242 First Publ...This article corrects the following:Volume 2 Issue 4 Journal of Dynamics,Monitoring and Diagnostics Inter-shaft Bearing Fault Diagnosis Based on Aero-engine System:A Benchmarking Dataset Study Pages:228-242 First Published online:03 August 2023 DOI:https://doi.org/10.37965/jdmd.2023.314 On page 228 of the PDF,the following correction should be noted.The title of the above paper was night on the journal website but wrong in the published PDF version.An updated PDF version of it is provided below.展开更多
Radiative cooling systems(RCSs)possess the distinctive capability to dissipate heat energy via solar and thermal radiation,making them suitable for thermal regulation and energy conservation applications,essential for...Radiative cooling systems(RCSs)possess the distinctive capability to dissipate heat energy via solar and thermal radiation,making them suitable for thermal regulation and energy conservation applications,essential for mitigating the energy crisis.A comprehensive review connecting the advancements in engineered radiative cooling systems(ERCSs),encompassing material and structural design as well as thermal and energy-related applications,is currently absent.Herein,this review begins with a concise summary of the essential concepts of ERCSs,followed by an introduction to engineered materials and structures,containing nature-inspired designs,chromatic materials,meta-structural configurations,and multilayered constructions.It subsequently encapsulates the primary applications,including thermal-regulating textiles and energy-saving devices.Next,it highlights the challenges of ERCSs,including maximized thermoregulatory effects,environmental adaptability,scalability and sustainability,and interdisciplinary integration.It seeks to offer direction for forthcoming fundamental research and industrial advancement of radiative cooling systems in real-world applications.展开更多
With the continuous advancement and maturation of technologies such as big data,artificial intelligence,virtual reality,robotics,human-machine collaboration,and augmented reality,many enterprises are finding new avenu...With the continuous advancement and maturation of technologies such as big data,artificial intelligence,virtual reality,robotics,human-machine collaboration,and augmented reality,many enterprises are finding new avenues for digital transformation and intelligent upgrading.Industry 5.0,a further extension and development of Industry 4.0,has become an important development trend in industry with more emphasis on human-centered sustainability and flexibility.Accordingly,both the industrial metaverse and digital twins have attracted much attention in this new era.However,the relationship between them is not clear enough.In this paper,a comparison between digital twins and the metaverse in industry is made firstly.Then,we propose the concept and framework of Digital Twin Systems Engineering(DTSE)to demonstrate how digital twins support the industrial metaverse in the era of Industry 5.0 by integrating systems engineering principles.Furthermore,we discuss the key technologies and challenges of DTSE,in particular how artificial intelligence enhances the application of DTSE.Finally,a specific application scenario in the aviation field is presented to illustrate the application prospects of DTSE.展开更多
Robustness against measurement uncertainties is crucial for gas turbine engine diagnosis.While current research focuses mainly on measurement noise,measurement bias remains challenging.This study proposes a novel perf...Robustness against measurement uncertainties is crucial for gas turbine engine diagnosis.While current research focuses mainly on measurement noise,measurement bias remains challenging.This study proposes a novel performance-based fault detection and identification(FDI)strategy for twin-shaft turbofan gas turbine engines and addresses these uncertainties through a first-order Takagi-Sugeno-Kang fuzzy inference system.To handle ambient condition changes,we use parameter correction to preprocess the raw measurement data,which reduces the FDI’s system complexity.Additionally,the power-level angle is set as a scheduling parameter to reduce the number of rules in the TSK-based FDI system.The data for designing,training,and testing the proposed FDI strategy are generated using a component-level turbofan engine model.The antecedent and consequent parameters of the TSK-based FDI system are optimized using the particle swarm optimization algorithm and ridge regression.A robust structure combining a specialized fuzzy inference system with the TSK-based FDI system is proposed to handle measurement biases.The performance of the first-order TSK-based FDI system and robust FDI structure are evaluated through comprehensive simulation studies.Comparative studies confirm the superior accuracy of the first-order TSK-based FDI system in fault detection,isolation,and identification.The robust structure demonstrates a 2%-8%improvement in the success rate index under relatively large measurement bias conditions,thereby indicating excellent robustness.Accuracy against significant bias values and computation time are also evaluated,suggesting that the proposed robust structure has desirable online performance.This study proposes a novel FDI strategy that effectively addresses measurement uncertainties.展开更多
The operating environment of the diesel engine air path system is complex and may be affected by external random disturbances.Potentially leading to faults.This paper addresses the fault-tolerant control problem of th...The operating environment of the diesel engine air path system is complex and may be affected by external random disturbances.Potentially leading to faults.This paper addresses the fault-tolerant control problem of the diesel engine air path system,assuming that the system may simultaneously be affected by actuator faults and external random disturbances,a disturbance observer-based sliding mode controller is designed.Through the linear matrix inequality technique for solving observer and controller gains,optimal gain matrices can be obtained,eliminating the manual adjustment process of controller parameters and reducing the chattering phenomenon of the sliding mode surface.Finally,the effectiveness of the proposed method is verified through simulation analysis.展开更多
In the last decade,space solar power satellites(SSPSs)have been conceived to support net-zero carbon emissions and have attracted considerable attention.Electric energy is transmitted to the ground via a microwave pow...In the last decade,space solar power satellites(SSPSs)have been conceived to support net-zero carbon emissions and have attracted considerable attention.Electric energy is transmitted to the ground via a microwave power beam,a technology known as microwave power transmission(MPT).Due to the vast transmission distance of tens of thousands of kilometers,the power transmitting antenna array must span up to 1 kilometer in diameter.At the same time,the size of the rectifying array on the ground should extend over a few kilometers.This makes the MPT system of SSPSs significantly larger than the existing aerospace engineering system.To design and operate a rational MPT system,comprehensive optimization is required.Taking the space MPT system engineering into consideration,a novel multi-objective optimization function is proposed and further analyzed.The multi-objective optimization problem is modeled mathematically.Beam collection efficiency(BCE)is the primary factor,followed by the thermal management capability.Some tapers,designed to solve the conflict between BCE and the thermal problem,are reviewed.In addition to these two factors,rectenna design complexity is included as a functional factor in the optimization objective.Weight coefficients are assigned to these factors to prioritize them.Radiating planar arrays with different aperture illumination fields are studied,and their performances are compared using the multi-objective optimization function.Transmitting array size,rectifying array size,transmission distance,and transmitted power remaine constant in various cases,ensuring fair comparisons.The analysis results show that the proposed optimization function is effective in optimizing and selecting the MPT system architecture.It is also noted that the multi-objective optimization function can be expanded to include other factors in the future.展开更多
Agricultural land development is a pivotal strategy for addressing the global food security crisis.Barren grassland,especially those in mountainous regions,constitutes critical areas where cultivation can substantiall...Agricultural land development is a pivotal strategy for addressing the global food security crisis.Barren grassland,especially those in mountainous regions,constitutes critical areas where cultivation can substantially enhance land resources.This study highlights the necessity for a precise correlation between land development initiatives and constraints in order to optimize efficiency and enhance the effectiveness of such projects,with the core being the seamless integration of land development engineering and techniques to eliminate agricultural constraints.This study employs a systems engineering approach to classify improvement factors into mobile and fixed categories,elucidating the integration methods of constraint factors.Adhering to the Wooden Barrel Principle,these constraints were rigorously analyzed based on soil quality,land topography,water availability,and agricultural infrastructure.An innovative method of engineering type combination is proposed,which effectively explains the correlation between natural factors combination,project type combination,and target factors combination.It provides a convenient way for the selection of barren grassland development projects and lays a foundation for land planning,development project establishment,program selection,engineering design,and budget preparation.Taking Tang County of China as an example,it is divided into 19 factor improvement areas,a quick reference table of engineering types is established,and 14 main types of engineering combinations are obtained,which lays a foundation for the application of theoretical framework in practice.展开更多
The intake system of a racing engine plays a crucial role in determining its performance,particularly in terms of volumetric efficiency,power output,and throttle response.According to Formula Society of Automotive Eng...The intake system of a racing engine plays a crucial role in determining its performance,particularly in terms of volumetric efficiency,power output,and throttle response.According to Formula Society of Automotive Engineers(FSAE)regulations,the engine intake systemmust incorporate a 20mmdiameter flow-limiting valve within the intake manifold.This restriction significantly reduces the airflow into the engine,leading to a substantial drop in power output.To mitigate this limitation,the intake system requires a redesign.In this study,theoretical calculations and one-dimensional thermodynamic simulations are employed to determine the optimal parameters for the intake system.A numerical simulation of the intake system’s flow field is then conducted to refine its structure and layout.Finally,experiments are performed on an engine equipped with the optimized intake system,and its feasibility is evaluated based on experimental results.Thefindings indicate that the maximumengine torque increases from56.36 to 59.91 N⋅m,while the maximum power output rises from 59.16 to 63.94 kW.To further enhance performance and adaptability across different competitions,a variable-length intakemanifold control system is also designed,improving both power delivery and overall operational stability of the racing car.展开更多
The research aimed to construct an intelligent review system for construction projects based on Building Information Modeling(BIM)and rule engines.By establishing a BIM data standard system and utilizing Structured Na...The research aimed to construct an intelligent review system for construction projects based on Building Information Modeling(BIM)and rule engines.By establishing a BIM data standard system and utilizing Structured Naming Language(SNL)to formalize review rules,combined with model visualization and scene recognition technology,a cloud native platform with automated review capabilities has been developed.The pilot application shows that the system can effectively improve the efficiency and accuracy of planning and construction drawing review,providing a feasible technical solution for digital engineering review.展开更多
In nuclear power engineering,the quality requirements for concrete are extremely stringent.Concrete structures must exhibit high durability to withstand the effects of nuclear radiation,chemical corrosion,and environm...In nuclear power engineering,the quality requirements for concrete are extremely stringent.Concrete structures must exhibit high durability to withstand the effects of nuclear radiation,chemical corrosion,and environmental changes.In particular,nuclear power projects impose higher design standards and safety requirements regarding concrete density.Traditional manual vibration and visual inspection methods are difficult to ensure the required level of concrete compaction.This paper presents an intelligent vibration technology for concrete in nuclear power engineering to enhance construction quality and efficiency.By integrating intelligent sensors,control systems,and data processing algorithms,the technology enables real-time monitoring and evaluation of the vibration process.Results show that intelligent vibration technology effectively ensures the density and uniformity of concrete in nuclear power engineering,thereby improving structural safety and reliability.展开更多
This study introduces the type-I heavy-tailed Burr XII(TIHTBXII)distribution,a highly flexible and robust statistical model designed to address the limitations of conventional distributions in analyzing data character...This study introduces the type-I heavy-tailed Burr XII(TIHTBXII)distribution,a highly flexible and robust statistical model designed to address the limitations of conventional distributions in analyzing data characterized by skewness,heavy tails,and diverse hazard behaviors.We meticulously develop the TIHTBXII’s mathematical foundations,including its probability density function(PDF),cumulative distribution function(CDF),and essential statistical properties,crucial for theoretical understanding and practical application.A comprehensive Monte Carlo simulation evaluates four parameter estimation methods:maximum likelihood(MLE),maximum product spacing(MPS),least squares(LS),and weighted least squares(WLS).The simulation results consistently show that as sample sizes increase,the Bias and RMSE of all estimators decrease,with WLS and LS often demonstrating superior and more stable performance.Beyond theoretical development,we present a practical application of the TIHTBXII distribution in constructing a group acceptance sampling plan(GASP)for truncated life tests.This application highlights how the TIHTBXII model can optimize quality control decisions by minimizing the average sample number(ASN)while effectively managing consumer and producer risks.Empirical validation using real-world datasets,including“Active Repair Duration,”“Groundwater Contaminant Measurements,”and“Dominica COVID-19 Mortality,”further demonstrates the TIHTBXII’s superior fit compared to existing models.Our findings confirm the TIHTBXII distribution as a powerful and reliable alternative for accurately modeling complex data in fields such as reliability engineering and quality assessment,leading to more informed and robust decision-making.展开更多
Engineered water systems such as wastewater treatment plants(WWTPs)are potential reservoirs of various biological risk factors(BRFs),including pathogens,antibiotic resistance genes(ARGs),and virulence factors(VFs).Cur...Engineered water systems such as wastewater treatment plants(WWTPs)are potential reservoirs of various biological risk factors(BRFs),including pathogens,antibiotic resistance genes(ARGs),and virulence factors(VFs).Currently,a BRF database relevant to engineered water systems on a global geographic scale is lacking.Here,we present the Global Wastewater Pathogen Database(GWPD),an online database that provides information on the diversity,abundance,and distribution of BRFs from 1302 metagenome samples obtained from 186 cities,68 countries,and six continents.We sorted these samples into six types:sewer networks,influent,anoxic activated sludge,oxic activated sludge,effluent,and receiving/natural waters.In total,476 pathogens,442 ARGs,and 246 VFs were identified.As a multifunctional database,GWPD provides an interactive visualization of these BRFs in a world map,an information retrieval interface,and an online one-click service for BRF annotation from metagenome sequencing data.GWPD is built on a web service framework,which can be readily extended to future versions of GWPD by adding more functional modules and connecting to other data sources,such as epidemic databases,to support risk assessment and control in the context of“One Health.”展开更多
Xiyu conglomerate is a significant and extensively distributed geological formation in western China.A clear understanding of its properties and the establishment of a classification system are essential for selecting...Xiyu conglomerate is a significant and extensively distributed geological formation in western China.A clear understanding of its properties and the establishment of a classification system are essential for selecting appropriate research methods to investigate its engineering mechanical behavior.Based on geological data from eight typical Xiyu conglomerate geological belts and seven hydropower projects,this study summarizes the main engineering geological characteristics,and analyzes the fabric characteristics of various components of the conglomerate through laboratory tests and statistical analysis.A comprehensive classification system is proposed for Xiyu conglomerate based on two key criteria:(1)grain size distribution,quantified by the d_(50)(median grain diameter),and(2)cementation type,identified via mineralogical and geochemical analysis.This system divides Xiyu conglomerate into nine distinct categories,each defined by specific engineering geological and petrofabric properties.The results reveal that,even within the same region,the grain size composition and distribution of Xiyu conglomerate are highly heterogeneous.While the chemical composition of the cementing materials is generally consistent,notable differences in cement properties arise primarily from variations in mineral content,particularly the proportion of calcareous material(dolomite,calcite,and quartz).Conglomerates with gray or grayish-blue matrices typically exhibit higher calcareous content,whereas those with earth-yellow or khaki matrices contain less calcareous material and are predominantly argillaceous-cemented.Additionally,Xiyu conglomerate shows higher porosity compared to conventional rocks.The proposed classification method based on engineering geological and fabric characteristics offers a geological basis for further determining the engineering mechanical properties of various Xiyu conglomerate types.This approach holds potential for addressing the challenges related to unclear classification and difficulty in accurately defining mechanical parameters for Xiyu conglomerate across different regions.展开更多
The rock mass rating(RMR)system is one of the most commonly used methods for classifying rock masses in underground engineering.Uncertainty of RMR values can signifi cantly aff ect the safety of underground projects.I...The rock mass rating(RMR)system is one of the most commonly used methods for classifying rock masses in underground engineering.Uncertainty of RMR values can signifi cantly aff ect the safety of underground projects.In this regard,we proposed a reliable rating approach for classifying rock masses based on the reliability theory.This theory was incorporated into the RMR system to establish the functions of rock masses of different classifications.By analyzing the probability distribution patterns of various parameters used in the RMR system and using the Monte Carlo method to calculate the reliability probability of surrounding rock belonging to each classifi cation,reliable RMR values for the rock mass to be excavated can be obtained.The results demonstrate that it is feasible to adopt the reliability theory in classifi cation tasks considering the randomness characteristics of rock and soil.As verified through a case study of the Lushan Tunnel project,the proposed approach can be used to obtain the probability of the uncertainty of the calculated RMR values of underground engineering rock masses,and the calculation results are consistent with reality.The proposed approach can serve as a reference for studies in other fi elds and also applies to other rock mass classifi cation methods.展开更多
This study explores the feasibility of constructing an intelligent educational evaluation system based on the CIPP model and artificial intelligence technology in the context of new engineering disciplines.By integrat...This study explores the feasibility of constructing an intelligent educational evaluation system based on the CIPP model and artificial intelligence technology in the context of new engineering disciplines.By integrating the CIPP model with AI technology,a novel intelligent educational evaluation system was designed.Through experimental validation and case studies,the system demonstrated significant effectiveness in improving teaching quality,facilitating personalized student development,and optimizing educational resource allocation.Additionally,the study predicts potential changes this system could bring to the education industry and proposes relevant policy recommendations.Although the current research has limitations,with technological advancements in the future,this system is expected to provide stronger support for innovations in engineering education models.展开更多
The advancement of Internet of Things(IoT)technology is driving industries toward intelligent digital transformation,highlighting the crucial role of software engineering.Despite this,the integration of software engin...The advancement of Internet of Things(IoT)technology is driving industries toward intelligent digital transformation,highlighting the crucial role of software engineering.Despite this,the integration of software engineering into IoT engineering education remains underexplored.To address this gap,the School of Software at North University of China,in collaboration with QST Innovation Technology Group Co.,Ltd.(QST),has developed an innovative educational mechanism.This initiative focuses on the software engineering IoT track and optimizes the teaching process through the outcome-based education(OBE)concept.It incorporates military-industrial characteristics,introduces advanced information and technology curricula,and enhances laboratory infrastructure.The goal is to cultivate innovative talents with unique capabilities,thereby fostering the comprehensive development and application of IoT technology.展开更多
This paper investigates the reliability of internal marine combustion engines using an integrated approach that combines Fault Tree Analysis(FTA)and Bayesian Networks(BN).FTA provides a structured,top-down method for ...This paper investigates the reliability of internal marine combustion engines using an integrated approach that combines Fault Tree Analysis(FTA)and Bayesian Networks(BN).FTA provides a structured,top-down method for identifying critical failure modes and their root causes,while BN introduces flexibility in probabilistic reasoning,enabling dynamic updates based on new evidence.This dual methodology overcomes the limitations of static FTA models,offering a comprehensive framework for system reliability analysis.Critical failures,including External Leakage(ELU),Failure to Start(FTS),and Overheating(OHE),were identified as key risks.By incorporating redundancy into high-risk components such as pumps and batteries,the likelihood of these failures was significantly reduced.For instance,redundant pumps reduced the probability of ELU by 31.88%,while additional batteries decreased the occurrence of FTS by 36.45%.The results underscore the practical benefits of combining FTA and BN for enhancing system reliability,particularly in maritime applications where operational safety and efficiency are critical.This research provides valuable insights for maintenance planning and highlights the importance of redundancy in critical systems,especially as the industry transitions toward more autonomous vessels.展开更多
文摘A new reliability allocation model has been built for engine system, which is a repairable system, and consists of a large number of mechanical components. The cost and reliability are taken as objective function and constraint condition respectively. The parameters of components lifetime distribution are given as decision variables, and the component lifetimes are assumed to follow that Weibull distribution. The allocation is separated into two steps to reduce calculated amount of one allocation. Genetic algorithm and Monte Carlo method are applied to solve distribution parameters and system cost separately.
文摘The global demand for transport energy is large, growing, and primarily met by petroleum-derived liquid fuels powering internal combustion engines (ICEs). Moreover, the demand for jet fuel and diesel is projected to grow faster than the demand for gasoline in the future, and is likely to result in low-octane gasoline components becoming more readily available. Significant initiatives with varying motivations are taking place to develop the battery electric vehicle (BEV) and the fuel cell as alternatives to ICE vehicles, and to establish fuels such as biofuels and natural gas as alternatives to conventional liquid fuels. However, each of these alternatives starts from a very low base and faces significant barriers to fast and unrestrained growth;thus, transport—and particularly commercial transport—will continue to be largely powered by ICEs running on petroleum-based liquid fuels for decades to come. Hence, the sustainability of transport in terms of affordability, energy security, and impact on greenhouse gas (GHG) emissions and air quality can only be ensured by improving ICEs. Indeed, ICEs will continue to improve while using current market fuels, through improvements in combustion, control, and after-treatment systems, assisted by partial electrification in the form of hybridization. However, there is even more scope for improvement through the development of fuel/engine systems that can additionally leverage benefits in fuels manufacture and use components that may be readily available. Gasoline compression ignition (GCI), which uses low-octane gasoline in a compression ignition engine, is one such example. GCI would enable diesel-like efficiencies while making it easier to control nitrogen oxides (NOx) and particulates at a lower cost compared with modern diesel engines. Octane on demand (OOD) also helps to ensure optimum use of available fuel anti-knock quality, and thus improves the overall efficiency of the system.
基金Funding of Jiangsu Innovation Program for Graduate Education (CXLX11_0213)Aeronautical Science Foundation of China (2010ZB52011)
文摘A new hybrid control scheme is presented with a robust multiple model fusion control（RMMFC） law for a UH-60 helicopter and an active disturbance rejection control（ADRC） controller for its engines.This scheme is a control design method with every subsystem designed separately but fully considering the couplings between them.With three subspaces with respect to forward flight velocity,a RMMFC is proposed to devise a four-loop reference signal tracing control for the helicopter,which escapes the closed-loop system from unstable state due to the extreme complexity of this integrated nonlinear system.The engines are controlled by the proposed ADRC decoupling controller,which fully takes advantage of a good compensation ability for unmodeled dynamics and extra disturbances,so as to compensate torque disturbance in power turbine speed loop.By simulating a forward acceleration flight task,the RMMFC for the helicopter is validated.It is apparent that the integrated helicopter and engine system（IHES） has much better dynamic performance under the new control scheme.Especially in the switching process,the large transient is significantly weakened,and smooth transition among candidate controllers is achieved.Over the entire simulation task,the droop of power turbine speed with the proposed ADRC controller is significantly slighter than with the conventional PID controller,and the response time of the former is much faster than the latter.By simulating a rapid climb and descent flight task,the results also show the feasibility for the application of the proposed multiple model fusion control.Although there is aggressive power demand in this maneuver,the droop of power turbine speed with an ADRC controller is smaller than using a PID controller.The control performance for helicopter and engine is enhanced by adopting this hybrid control scheme,and simulation results in other envelope state give proofs of robustness for this new scheme.
文摘This article corrects the following:Volume 2 Issue 4 Journal of Dynamics,Monitoring and Diagnostics Inter-shaft Bearing Fault Diagnosis Based on Aero-engine System:A Benchmarking Dataset Study Pages:228-242 First Published online:03 August 2023 DOI:https://doi.org/10.37965/jdmd.2023.314 On page 228 of the PDF,the following correction should be noted.The title of the above paper was night on the journal website but wrong in the published PDF version.An updated PDF version of it is provided below.
基金support from the Contract Research(“Development of Breathable Fabrics with Nano-Electrospun Membrane”,CityU ref.:9231419“Research and application of antibacterial and healing-promoting smart nanofiber dressing for children’s burn wounds”,CityU ref:PJ9240111)+1 种基金the National Natural Science Foundation of China(“Study of Multi-Responsive Shape Memory Polyurethane Nanocomposites Inspired by Natural Fibers”,Grant No.51673162)Startup Grant of CityU(“Laboratory of Wearable Materials for Healthcare”,Grant No.9380116).
文摘Radiative cooling systems(RCSs)possess the distinctive capability to dissipate heat energy via solar and thermal radiation,making them suitable for thermal regulation and energy conservation applications,essential for mitigating the energy crisis.A comprehensive review connecting the advancements in engineered radiative cooling systems(ERCSs),encompassing material and structural design as well as thermal and energy-related applications,is currently absent.Herein,this review begins with a concise summary of the essential concepts of ERCSs,followed by an introduction to engineered materials and structures,containing nature-inspired designs,chromatic materials,meta-structural configurations,and multilayered constructions.It subsequently encapsulates the primary applications,including thermal-regulating textiles and energy-saving devices.Next,it highlights the challenges of ERCSs,including maximized thermoregulatory effects,environmental adaptability,scalability and sustainability,and interdisciplinary integration.It seeks to offer direction for forthcoming fundamental research and industrial advancement of radiative cooling systems in real-world applications.
基金Supported by Beijing Municipal Natural Science Foundation of China(Grant No.24JL002)China Postdoctoral Science Foundation(Grant No.2024M754054)+2 种基金National Natural Science Foundation of China(Grant No.52120105008)Beijing Municipal Outstanding Young Scientis Program of Chinathe New Cornerstone Science Foundation through the XPLORER PRIZE。
文摘With the continuous advancement and maturation of technologies such as big data,artificial intelligence,virtual reality,robotics,human-machine collaboration,and augmented reality,many enterprises are finding new avenues for digital transformation and intelligent upgrading.Industry 5.0,a further extension and development of Industry 4.0,has become an important development trend in industry with more emphasis on human-centered sustainability and flexibility.Accordingly,both the industrial metaverse and digital twins have attracted much attention in this new era.However,the relationship between them is not clear enough.In this paper,a comparison between digital twins and the metaverse in industry is made firstly.Then,we propose the concept and framework of Digital Twin Systems Engineering(DTSE)to demonstrate how digital twins support the industrial metaverse in the era of Industry 5.0 by integrating systems engineering principles.Furthermore,we discuss the key technologies and challenges of DTSE,in particular how artificial intelligence enhances the application of DTSE.Finally,a specific application scenario in the aviation field is presented to illustrate the application prospects of DTSE.
文摘Robustness against measurement uncertainties is crucial for gas turbine engine diagnosis.While current research focuses mainly on measurement noise,measurement bias remains challenging.This study proposes a novel performance-based fault detection and identification(FDI)strategy for twin-shaft turbofan gas turbine engines and addresses these uncertainties through a first-order Takagi-Sugeno-Kang fuzzy inference system.To handle ambient condition changes,we use parameter correction to preprocess the raw measurement data,which reduces the FDI’s system complexity.Additionally,the power-level angle is set as a scheduling parameter to reduce the number of rules in the TSK-based FDI system.The data for designing,training,and testing the proposed FDI strategy are generated using a component-level turbofan engine model.The antecedent and consequent parameters of the TSK-based FDI system are optimized using the particle swarm optimization algorithm and ridge regression.A robust structure combining a specialized fuzzy inference system with the TSK-based FDI system is proposed to handle measurement biases.The performance of the first-order TSK-based FDI system and robust FDI structure are evaluated through comprehensive simulation studies.Comparative studies confirm the superior accuracy of the first-order TSK-based FDI system in fault detection,isolation,and identification.The robust structure demonstrates a 2%-8%improvement in the success rate index under relatively large measurement bias conditions,thereby indicating excellent robustness.Accuracy against significant bias values and computation time are also evaluated,suggesting that the proposed robust structure has desirable online performance.This study proposes a novel FDI strategy that effectively addresses measurement uncertainties.
基金Supported by the National Key R&D Program of China(2021YFB2011300)the National Natural Science Foundation of China(52275044,52205299)+1 种基金the Zhejiang Provincial Natural Science Foundation of China(Z23E050032)the China Postdoctoral Science Foundation(2022M710304).
文摘The operating environment of the diesel engine air path system is complex and may be affected by external random disturbances.Potentially leading to faults.This paper addresses the fault-tolerant control problem of the diesel engine air path system,assuming that the system may simultaneously be affected by actuator faults and external random disturbances,a disturbance observer-based sliding mode controller is designed.Through the linear matrix inequality technique for solving observer and controller gains,optimal gain matrices can be obtained,eliminating the manual adjustment process of controller parameters and reducing the chattering phenomenon of the sliding mode surface.Finally,the effectiveness of the proposed method is verified through simulation analysis.
文摘In the last decade,space solar power satellites(SSPSs)have been conceived to support net-zero carbon emissions and have attracted considerable attention.Electric energy is transmitted to the ground via a microwave power beam,a technology known as microwave power transmission(MPT).Due to the vast transmission distance of tens of thousands of kilometers,the power transmitting antenna array must span up to 1 kilometer in diameter.At the same time,the size of the rectifying array on the ground should extend over a few kilometers.This makes the MPT system of SSPSs significantly larger than the existing aerospace engineering system.To design and operate a rational MPT system,comprehensive optimization is required.Taking the space MPT system engineering into consideration,a novel multi-objective optimization function is proposed and further analyzed.The multi-objective optimization problem is modeled mathematically.Beam collection efficiency(BCE)is the primary factor,followed by the thermal management capability.Some tapers,designed to solve the conflict between BCE and the thermal problem,are reviewed.In addition to these two factors,rectenna design complexity is included as a functional factor in the optimization objective.Weight coefficients are assigned to these factors to prioritize them.Radiating planar arrays with different aperture illumination fields are studied,and their performances are compared using the multi-objective optimization function.Transmitting array size,rectifying array size,transmission distance,and transmitted power remaine constant in various cases,ensuring fair comparisons.The analysis results show that the proposed optimization function is effective in optimizing and selecting the MPT system architecture.It is also noted that the multi-objective optimization function can be expanded to include other factors in the future.
基金funded by Science and Technology Project of Hebei Education Department[QN2023085].
文摘Agricultural land development is a pivotal strategy for addressing the global food security crisis.Barren grassland,especially those in mountainous regions,constitutes critical areas where cultivation can substantially enhance land resources.This study highlights the necessity for a precise correlation between land development initiatives and constraints in order to optimize efficiency and enhance the effectiveness of such projects,with the core being the seamless integration of land development engineering and techniques to eliminate agricultural constraints.This study employs a systems engineering approach to classify improvement factors into mobile and fixed categories,elucidating the integration methods of constraint factors.Adhering to the Wooden Barrel Principle,these constraints were rigorously analyzed based on soil quality,land topography,water availability,and agricultural infrastructure.An innovative method of engineering type combination is proposed,which effectively explains the correlation between natural factors combination,project type combination,and target factors combination.It provides a convenient way for the selection of barren grassland development projects and lays a foundation for land planning,development project establishment,program selection,engineering design,and budget preparation.Taking Tang County of China as an example,it is divided into 19 factor improvement areas,a quick reference table of engineering types is established,and 14 main types of engineering combinations are obtained,which lays a foundation for the application of theoretical framework in practice.
基金supported by the Key Laboratory of Automotive Power Train and Electronics(Hubei University of Automotive Technology)(ZDK1201505)Auto Parts TechnologyHubei Province Collaborative Innovation Project(2015XTZX04).
文摘The intake system of a racing engine plays a crucial role in determining its performance,particularly in terms of volumetric efficiency,power output,and throttle response.According to Formula Society of Automotive Engineers(FSAE)regulations,the engine intake systemmust incorporate a 20mmdiameter flow-limiting valve within the intake manifold.This restriction significantly reduces the airflow into the engine,leading to a substantial drop in power output.To mitigate this limitation,the intake system requires a redesign.In this study,theoretical calculations and one-dimensional thermodynamic simulations are employed to determine the optimal parameters for the intake system.A numerical simulation of the intake system’s flow field is then conducted to refine its structure and layout.Finally,experiments are performed on an engine equipped with the optimized intake system,and its feasibility is evaluated based on experimental results.Thefindings indicate that the maximumengine torque increases from56.36 to 59.91 N⋅m,while the maximum power output rises from 59.16 to 63.94 kW.To further enhance performance and adaptability across different competitions,a variable-length intakemanifold control system is also designed,improving both power delivery and overall operational stability of the racing car.
文摘The research aimed to construct an intelligent review system for construction projects based on Building Information Modeling(BIM)and rule engines.By establishing a BIM data standard system and utilizing Structured Naming Language(SNL)to formalize review rules,combined with model visualization and scene recognition technology,a cloud native platform with automated review capabilities has been developed.The pilot application shows that the system can effectively improve the efficiency and accuracy of planning and construction drawing review,providing a feasible technical solution for digital engineering review.
基金The Advanced Civil Design and Construction Technology Joint LAB of Nuclear Engineering(Project No.:KY23015).
文摘In nuclear power engineering,the quality requirements for concrete are extremely stringent.Concrete structures must exhibit high durability to withstand the effects of nuclear radiation,chemical corrosion,and environmental changes.In particular,nuclear power projects impose higher design standards and safety requirements regarding concrete density.Traditional manual vibration and visual inspection methods are difficult to ensure the required level of concrete compaction.This paper presents an intelligent vibration technology for concrete in nuclear power engineering to enhance construction quality and efficiency.By integrating intelligent sensors,control systems,and data processing algorithms,the technology enables real-time monitoring and evaluation of the vibration process.Results show that intelligent vibration technology effectively ensures the density and uniformity of concrete in nuclear power engineering,thereby improving structural safety and reliability.
基金supported and funded by the Deanship of Scientific Research at Imam Mohammad Ibn Saud Islamic University(IMSIU)(Grant Number IMSIU-DDRSP2501).
文摘This study introduces the type-I heavy-tailed Burr XII(TIHTBXII)distribution,a highly flexible and robust statistical model designed to address the limitations of conventional distributions in analyzing data characterized by skewness,heavy tails,and diverse hazard behaviors.We meticulously develop the TIHTBXII’s mathematical foundations,including its probability density function(PDF),cumulative distribution function(CDF),and essential statistical properties,crucial for theoretical understanding and practical application.A comprehensive Monte Carlo simulation evaluates four parameter estimation methods:maximum likelihood(MLE),maximum product spacing(MPS),least squares(LS),and weighted least squares(WLS).The simulation results consistently show that as sample sizes increase,the Bias and RMSE of all estimators decrease,with WLS and LS often demonstrating superior and more stable performance.Beyond theoretical development,we present a practical application of the TIHTBXII distribution in constructing a group acceptance sampling plan(GASP)for truncated life tests.This application highlights how the TIHTBXII model can optimize quality control decisions by minimizing the average sample number(ASN)while effectively managing consumer and producer risks.Empirical validation using real-world datasets,including“Active Repair Duration,”“Groundwater Contaminant Measurements,”and“Dominica COVID-19 Mortality,”further demonstrates the TIHTBXII’s superior fit compared to existing models.Our findings confirm the TIHTBXII distribution as a powerful and reliable alternative for accurately modeling complex data in fields such as reliability engineering and quality assessment,leading to more informed and robust decision-making.
基金supported by the National Natural Science Foundation of China(52321005,52293441,52293443,52230004)the Shenzhen Stability Support Key Program in Colleges and Universities of China(GXWD20231127195344001)+3 种基金the Natural Science Foundation of Guangdong Basic and Applied Basic Research Foundation(2024A1515010085)the Shenzhen Overseas High-level Talents Research Startup Program(20200518750C)the Shenzhen Science and Technology Program(KQTD20190929172630447)the Open Project of the Key Laboratory of Environmental Biotechnology,CAS(KF2021006).
文摘Engineered water systems such as wastewater treatment plants(WWTPs)are potential reservoirs of various biological risk factors(BRFs),including pathogens,antibiotic resistance genes(ARGs),and virulence factors(VFs).Currently,a BRF database relevant to engineered water systems on a global geographic scale is lacking.Here,we present the Global Wastewater Pathogen Database(GWPD),an online database that provides information on the diversity,abundance,and distribution of BRFs from 1302 metagenome samples obtained from 186 cities,68 countries,and six continents.We sorted these samples into six types:sewer networks,influent,anoxic activated sludge,oxic activated sludge,effluent,and receiving/natural waters.In total,476 pathogens,442 ARGs,and 246 VFs were identified.As a multifunctional database,GWPD provides an interactive visualization of these BRFs in a world map,an information retrieval interface,and an online one-click service for BRF annotation from metagenome sequencing data.GWPD is built on a web service framework,which can be readily extended to future versions of GWPD by adding more functional modules and connecting to other data sources,such as epidemic databases,to support risk assessment and control in the context of“One Health.”
基金Xinjiang Water Science and Technology Special Project,Grant/Award Numbers:XSKJ-2022-05,XSKJ-2023-30State Grid Co.,LTD.Technology Project,Grant/Award Number:5108-202218280A-2-301-XG。
文摘Xiyu conglomerate is a significant and extensively distributed geological formation in western China.A clear understanding of its properties and the establishment of a classification system are essential for selecting appropriate research methods to investigate its engineering mechanical behavior.Based on geological data from eight typical Xiyu conglomerate geological belts and seven hydropower projects,this study summarizes the main engineering geological characteristics,and analyzes the fabric characteristics of various components of the conglomerate through laboratory tests and statistical analysis.A comprehensive classification system is proposed for Xiyu conglomerate based on two key criteria:(1)grain size distribution,quantified by the d_(50)(median grain diameter),and(2)cementation type,identified via mineralogical and geochemical analysis.This system divides Xiyu conglomerate into nine distinct categories,each defined by specific engineering geological and petrofabric properties.The results reveal that,even within the same region,the grain size composition and distribution of Xiyu conglomerate are highly heterogeneous.While the chemical composition of the cementing materials is generally consistent,notable differences in cement properties arise primarily from variations in mineral content,particularly the proportion of calcareous material(dolomite,calcite,and quartz).Conglomerates with gray or grayish-blue matrices typically exhibit higher calcareous content,whereas those with earth-yellow or khaki matrices contain less calcareous material and are predominantly argillaceous-cemented.Additionally,Xiyu conglomerate shows higher porosity compared to conventional rocks.The proposed classification method based on engineering geological and fabric characteristics offers a geological basis for further determining the engineering mechanical properties of various Xiyu conglomerate types.This approach holds potential for addressing the challenges related to unclear classification and difficulty in accurately defining mechanical parameters for Xiyu conglomerate across different regions.
基金supported by the National Natural Science Foundation of China [Grant No.52079077]China Postdoctoral Science Foundation (Grant No. 2022M711962)。
文摘The rock mass rating(RMR)system is one of the most commonly used methods for classifying rock masses in underground engineering.Uncertainty of RMR values can signifi cantly aff ect the safety of underground projects.In this regard,we proposed a reliable rating approach for classifying rock masses based on the reliability theory.This theory was incorporated into the RMR system to establish the functions of rock masses of different classifications.By analyzing the probability distribution patterns of various parameters used in the RMR system and using the Monte Carlo method to calculate the reliability probability of surrounding rock belonging to each classifi cation,reliable RMR values for the rock mass to be excavated can be obtained.The results demonstrate that it is feasible to adopt the reliability theory in classifi cation tasks considering the randomness characteristics of rock and soil.As verified through a case study of the Lushan Tunnel project,the proposed approach can be used to obtain the probability of the uncertainty of the calculated RMR values of underground engineering rock masses,and the calculation results are consistent with reality.The proposed approach can serve as a reference for studies in other fi elds and also applies to other rock mass classifi cation methods.
基金Liaoning Provincial Social Science Planning Fund“Research on the Educational Intelligent Evaluation System Based on the CIPP Model and Artificial Intelligence under the Background of New Engineering”(L22BTJ005)。
文摘This study explores the feasibility of constructing an intelligent educational evaluation system based on the CIPP model and artificial intelligence technology in the context of new engineering disciplines.By integrating the CIPP model with AI technology,a novel intelligent educational evaluation system was designed.Through experimental validation and case studies,the system demonstrated significant effectiveness in improving teaching quality,facilitating personalized student development,and optimizing educational resource allocation.Additionally,the study predicts potential changes this system could bring to the education industry and proposes relevant policy recommendations.Although the current research has limitations,with technological advancements in the future,this system is expected to provide stronger support for innovations in engineering education models.
基金supported in part by the Universityindustry Collaborative Education Program of the Ministry of Education under Grant No.202102383004。
文摘The advancement of Internet of Things(IoT)technology is driving industries toward intelligent digital transformation,highlighting the crucial role of software engineering.Despite this,the integration of software engineering into IoT engineering education remains underexplored.To address this gap,the School of Software at North University of China,in collaboration with QST Innovation Technology Group Co.,Ltd.(QST),has developed an innovative educational mechanism.This initiative focuses on the software engineering IoT track and optimizes the teaching process through the outcome-based education(OBE)concept.It incorporates military-industrial characteristics,introduces advanced information and technology curricula,and enhances laboratory infrastructure.The goal is to cultivate innovative talents with unique capabilities,thereby fostering the comprehensive development and application of IoT technology.
基金supported by Istanbul Technical University(Project No.45698)supported through the“Young Researchers’Career Development Project-training of doctoral students”of the Croatian Science Foundation.
文摘This paper investigates the reliability of internal marine combustion engines using an integrated approach that combines Fault Tree Analysis(FTA)and Bayesian Networks(BN).FTA provides a structured,top-down method for identifying critical failure modes and their root causes,while BN introduces flexibility in probabilistic reasoning,enabling dynamic updates based on new evidence.This dual methodology overcomes the limitations of static FTA models,offering a comprehensive framework for system reliability analysis.Critical failures,including External Leakage(ELU),Failure to Start(FTS),and Overheating(OHE),were identified as key risks.By incorporating redundancy into high-risk components such as pumps and batteries,the likelihood of these failures was significantly reduced.For instance,redundant pumps reduced the probability of ELU by 31.88%,while additional batteries decreased the occurrence of FTS by 36.45%.The results underscore the practical benefits of combining FTA and BN for enhancing system reliability,particularly in maritime applications where operational safety and efficiency are critical.This research provides valuable insights for maintenance planning and highlights the importance of redundancy in critical systems,especially as the industry transitions toward more autonomous vessels.
