Small modular reactor(SMR)belongs to the research forefront of nuclear reactor technology.Nowadays,advancement of intelligent control technologies paves a new way to the design and build of unmanned SMR.The autonomous...Small modular reactor(SMR)belongs to the research forefront of nuclear reactor technology.Nowadays,advancement of intelligent control technologies paves a new way to the design and build of unmanned SMR.The autonomous control process of SMR can be divided into three stages,say,state diagnosis,autonomous decision-making and coordinated control.In this paper,the autonomous state recognition and task planning of unmanned SMR are investigated.An operating condition recognition method based on the knowledge base of SMR operation is proposed by using the artificial neural network(ANN)technology,which constructs a basis for the state judgment of intelligent reactor control path planning.An improved reinforcement learning path planning algorithm is utilized to implement the path transfer decision-makingThis algorithm performs condition transitions with minimal cost under specified modes.In summary,the full range control path intelligent decision-planning technology of SMR is realized,thus provides some theoretical basis for the design and build of unmanned SMR in the future.展开更多
Lignans have been established as a privileged scaffold in drug discovery,particularly in anticancer and antioxidant properties.Concise and efficient construction of lignans and their derivatives in a single operation ...Lignans have been established as a privileged scaffold in drug discovery,particularly in anticancer and antioxidant properties.Concise and efficient construction of lignans and their derivatives in a single operation holds great medicinal significance for structure-activity relationship studies yet remains challenging.Drawing inspiration from the biosynthesis of lignans,we present a general,high-step-economy palladium-catalyzed reaction that converts simple chemical feedstocks into dehydrodibenzylbutyrolactone lignans through the in-situ construction and coupling of two phenylpropanoid molecules.The diversity of organoboronic acids and the editability of enyne provide a powerful platform for the rapid construction of lignan libraries,featuring 82 lignans analogs,collective syntheses of 10 distinct lignan skeletons,and 13 hybrid molecules combining pharmacophore fragments with drug and derivatives.The subtle combination of phosphine ligands with quinones for switching chemoselectivity is vital to the success of this protocol.展开更多
The modular design pattern revolutionizes the monolithic morphology of traditional spacecraft into the reconfigurable combination of modular units.However,due to the morphological changes,the effective takeover contro...The modular design pattern revolutionizes the monolithic morphology of traditional spacecraft into the reconfigurable combination of modular units.However,due to the morphological changes,the effective takeover control of the combination through multiple independent modules,including the controller and actuator modules,remains a challenge.In this paper,a robust takeover control scheme with high allocation accuracy,independent of precise inertia,is proposed for the reconfigurable combination in the presence of the inertia uncertainty,model parameters uncertainty,communication delay,and external disturbance.By reregulating the conditions for performance synthesis into a symmetric form with similar structure,a hybrid non-fragile H_(2)/H_(∞)controller is designed for handling two types of controller gain perturbations,achieving superior performance with less energy consumption through simultaneous perturbation suppression.Moreover,through temporarily storing the allocation signals in the initial stage to cover the upper bound of the communication delay,the proposed distributed dynamic allocation scheme enables the actuator modules to implement the control signals jointly to stabilize the combination.Distinguished from general allocators,the proposed high-precision allocation scheme under communication delay can not only ensure full exploitation of controller performance,but also dynamically adjust allocation coefficients based on energy consumption index of controller modules to prevent actuator saturation.Numerical simulations demonstrate the superiority of the proposed hybrid non-fragile controller and the allocation scheme.展开更多
This paper comprehensively explores the impulsive on-orbit inspection game problem utilizing reinforcement learning and game training methods.The purpose of the spacecraft is to inspect the entire surface of a non-coo...This paper comprehensively explores the impulsive on-orbit inspection game problem utilizing reinforcement learning and game training methods.The purpose of the spacecraft is to inspect the entire surface of a non-cooperative target with active maneuverability in front lighting.First,the impulsive orbital game problem is formulated as a turn-based sequential game problem.Second,several typical relative orbit transfers are encapsulated into modules to construct a parameterized action space containing discrete modules and continuous parameters,and multi-pass deep Q-networks(MPDQN)algorithm is used to implement autonomous decision-making.Then,a curriculum learning method is used to gradually increase the difficulty of the training scenario.The backtracking proportional self-play training framework is used to enhance the agent’s ability to defeat inconsistent strategies by building a pool of opponents.The behavior variations of the agents during training indicate that the intelligent game system gradually evolves towards an equilibrium situation.The restraint relations between the agents show that the agents steadily improve the strategy.The influence of various factors on game results is tested.展开更多
A brief concept study of a modular research aircraft with potential applications to Mars exploration is conducted.Considered are dimensional and mass constraints of a launch vehicle payload compartment,mission radius ...A brief concept study of a modular research aircraft with potential applications to Mars exploration is conducted.Considered are dimensional and mass constraints of a launch vehicle payload compartment,mission radius extension applying ground mobility and overall flight envelope extension using fixed-wing aerodynamics.Also,some lessons learned from NASA Mars Ingenuity flights are considered and addressed with few solutions.The modular system includes a fixed-wing design along with a number of smaller autonomous quadcopter UAVs,encapsulated inside a geodesic spherical support through a gimbal mechanism for ground mobility.Analyzed is the feasibility of allocating to these mini drones both scout and mapping tasks of complex terrain such as crater walls,canyons and cave systems that might hold key insights into the planet's geologic history.Once docked with the mothership fixed wing,the mini drones serve as a distributed propulsion system,for vertical take-off and landing and control,completely replacing control surfaces on the flying wing itself,its engine and landing gear.CFD and structural simulations have demonstrated the flight-ability in Mars conditions of a flying wing design along with scout drone prototypes with a pentagon-hexagon geodesic shell.Also demonstrated is the great flexibility of the suggested modular approach for various research applications and mission profiles on Mars and other planets or moons,improving overall reliability and mission radius.展开更多
With the increasing demand for secure infrastructure such as hydrogen refueling stations,chemical plants,and energy storage systems,the need for protective structures capable of withstanding close-in detonations has b...With the increasing demand for secure infrastructure such as hydrogen refueling stations,chemical plants,and energy storage systems,the need for protective structures capable of withstanding close-in detonations has become more critical.Existing design guidelines for protective walls(e.g.,UFC 3-340-02)primarily address mid-and far-field explosions,providing limited insights into near-field effects.Considering the effect of slight slopes(<40°)on reducing maximum reflected overpressure is deemed negligible.This study investigated the effectiveness of a reinforced concrete(RC)modular protection system(MPS)incorpo rating a diagonally tapered wall in attenuating re flected overpressures from closein detonations.Full-scale field experiments using a 51.3 kg TNT charge,representing the explosion energy of a typical hydrogen vessel rupture,demonstrated that a wall with a 7°slope significantly outperformed a vertical wall of equivalent concrete volume in terms of blast resistance.Observed structural responses included cracking,horizontal shear failure,and overturning.Complementary simulations using a validated computational fluid dynamics(CFD)model showed that the tapered wall reduced peak overpressure by 30%-40%compared to an equivalent vertical wall.This result highlights the potential of minor geometric modifications to enhance blast resilience.The tapered design effectively redirects incident blast waves,reducing localized damage while also conserving material,thus preserving modular benefits such as ease of transport and reusability.These findings suggest that diagonally tapered RC-based MPSs can offer a practical and resilient solution for industrial and military applications subject to near-field or sequential blast threats.展开更多
In clinical practice,the irregular shapes of traumas pose a significant challenge in rapidly manufacturing personalized scaffolds.To address these challenges,inspired by LEGO■ bricks,this study proposed a novel conce...In clinical practice,the irregular shapes of traumas pose a significant challenge in rapidly manufacturing personalized scaffolds.To address these challenges,inspired by LEGO■ bricks,this study proposed a novel concept of modular scaffolds and developed an innovative system based on machine vision for their rapid and intelligent assembly tailored to defect shapes.Trapezoidal interfaces effectively connect standardized bone units based on magnesium-doped silicate calcium,ensuring high stability of the modular scaffolds,with compressive strength up to 135 MPa and bending strength up to 17 MPa.Through self-developed defect recognition and reconstruction algorithms,defect recognition and personalized assembly schemes for bone scaffolds can be achieved autonomously.Modular scaffolds seamlessly integrate with surrounding bone tissue,promoting new bone growth,with no apparent differences compared to fully 3D printed integral scaffolds in the skull and femur repair experiments.In summary,the adoption of modular scaffolds not only integrates personalization and standardization but also satisfies the optimal treatment window.展开更多
Based on the analysis and research of the airworthiness objective of integrated modular avionics system(IMA),and the characteristics of IMA system’s comprehensive and complex cross-linking with other airborne systems...Based on the analysis and research of the airworthiness objective of integrated modular avionics system(IMA),and the characteristics of IMA system’s comprehensive and complex cross-linking with other airborne systems,the extraction strategy of IMA system’s compliance flight test subjects and the selection method of IMA system’s compliance flight test parameters are proposed.The data analysis method based on the abnormal probability matrix of the IMA system is proposed for the first time,and the abnormal state information of the IMA system can be quickly identified.The compliance flight test of the IMA system is completed with limited flight test resources,which achieves the purpose of saving flight test sorties and improving flight test efficiency.This research has been successfully applied to the airworthiness certification flight test of a certain civil transport aircraft in China,and can provide technical support for the subsequent type flight test.展开更多
Given the rapid growth of sustainable construction strategies globally and the importance of resiliency in civil infrastructure,it is crucial to adopt best practices.Modular construction is one such practice and is co...Given the rapid growth of sustainable construction strategies globally and the importance of resiliency in civil infrastructure,it is crucial to adopt best practices.Modular construction is one such practice and is considered a better alternative to conventional construction in terms of resilience,construction times,resource efficiency,and sustainability.However,the continued expansion of modular construction relies on quantifying and evaluating its sustainability and the purported benefits.This paper develops and checks feasibility through an integrated multi-level decision support framework to empirically evaluate the sustainability performances of single-family residential modular homes.Criteria and indicator development and calculation,benchmark scale establishment,quantitative and qualitative data collection from literature and surveys,and multi-criteria decision analysis are unique aspects of this framework.The results of the two case studies located in the Okanagan region,Canada showed that modular homes perform at a higher level of sustainability than their conventional counterparts across multiple metrics and levels related to environmental and economic factors.The modular homes scored eco-efficiency values of 62.5 and 56.0,respectively and fell into higher performance range.The proposed frame-work offers flexibility in examining different dimensions of sustainability,providing valuable insights into the key parameters that need to be addressed to enhance overall sustainability.This research,which integrates life cycle thinking and decision-making,helps the construction industry and,municipalities,governments,and pol-icymakers in making informed decisions on the selection of suitable construction methods in city developments and move towards a more resilient and sustainable sector.展开更多
The seismic intensity is generally high in the Qinghai-Tibet Plateau region of China.The seismic performance of the new prefabricated modular pressurized buildings used to solve the plateau response is insufficient.To...The seismic intensity is generally high in the Qinghai-Tibet Plateau region of China.The seismic performance of the new prefabricated modular pressurized buildings used to solve the plateau response is insufficient.To solve this problem,the small friction pendulum bearing(FPB)isolation design is proposed for modular pressurized buildings.Firstly,a simplified model of cross-truss support for the pressurized module is proposed to simplify the modeling and calculation of the pressurized buildings.The reasonability of the simplified model is verified by comparing the refined finite element model.Subsequently,according to the FPB design process for modular pressurized buildings,a small FPB for isolation is provided for a two-story modular pressurized building under 8-degree fortification earthquakes.Lastly,the seismic effectiveness and constructional feasibility of the isolation structure are verified compared with the non-isolated structure using dynamic time-history analysis.The study results show that the size of FPBs for modular pressurized buildings should consider both displacement and dimension requirements to weigh seismic isolation performance and installation feasibility,respectively.When adopting FPBs,the response of the structure is significantly reduced,and the seismic isolation effect is obvious.The proposed construction process can improve the seismic resilience of the prefabricated modular pressurized buildings by replacing post-earthquake damaged components quickly.It provides ideas for the seismic isolation design of the prefabricated modular pressurized buildings in high seismic intensity areas.展开更多
This article focuses on the municipal prefabricated bathroom station.It elaborates on its modular design concept,including key design points such as spatial layout,functional modules,and determination of key parameter...This article focuses on the municipal prefabricated bathroom station.It elaborates on its modular design concept,including key design points such as spatial layout,functional modules,and determination of key parameters;introduces the optimization of intelligent production processes,precision control,and integration of construction technology,and also mentions the verification of full lifecycle applications and quality control;as well as emphasizes the importance of BIM+IoT platform and looks forward to the future.展开更多
Modular arithmetic is a fundamental operation and plays an important role in public key cryptosystem. A new method and its theory evidence on the basis of modular arithmetic with large integer modulus-changeable modul...Modular arithmetic is a fundamental operation and plays an important role in public key cryptosystem. A new method and its theory evidence on the basis of modular arithmetic with large integer modulus-changeable modulus algorithm is proposed to improve the speed of the modular arithmetic in the presented paper. For changeable modulus algorithm, when modular computation of modulo n is difficult, it can be realized by computation of modulo n-1 and n-2 on the perquisite of easy modular computations of modulo n-1 and modulo n-2. The conclusion is that the new method is better than the direct method by computing the modular arithmetic operation with large modulus. Especially, when computations of modulo n-1 and modulo n-2 are easy and computation of modulo n is difficult, this new method will be faster and has more advantages than other algorithms on modular arithmetic. Lastly, it is suggested that the proposed method be applied in public key cryptography based on modular multiplication and modular exponentiation with large integer modulus effectively展开更多
A new modular solution to the state explosion problem caused by the Markov-based modular solution of dynamic multiple-phased systems is proposed. First, the solution makes full use of the static parts of dynamic multi...A new modular solution to the state explosion problem caused by the Markov-based modular solution of dynamic multiple-phased systems is proposed. First, the solution makes full use of the static parts of dynamic multiple-phased systems and constructs cross-phase dynamic modules by combining the dynamic modules of phase fault trees. Secondly, the system binary decision diagram （BDD） from a modularized multiple- phased system （MPS）is generated by using variable ordering and BDD operations. The computational formulations of the BDD node event probability are derived for various node links and the system reliability results are figured out. Finally, a hypothetical multiple-phased system is given to demonstrate the advantages of the dynamic modular solution when the Markov state space and the size of the system BDD are reduced.展开更多
The shape of a spacecraft is transitioning from monolithic,manual,and static to modular,autonomous,and dynamic.Modular Reconfigurable Spacecrafts(MRSs)offer better solutions than traditional monolithic spacecrafts in ...The shape of a spacecraft is transitioning from monolithic,manual,and static to modular,autonomous,and dynamic.Modular Reconfigurable Spacecrafts(MRSs)offer better solutions than traditional monolithic spacecrafts in several aspects,and may become the next generation of spacecraft systems with efficient design,fast deployment,flexible application,and convenient management.This paper reviews the development and technology of MRS from three aspects:Modularity,reconfigurability,and autonomy.Despite the progress of research on MRS,there is still a lack of unified standards and little understanding of related concepts.Based on the understanding of basic concepts,the studies conducted on MRS are reviewed to identify technical requirements and solutions.Aiming at the future development trend of MRS,a novel modular selfreconfigurable spacecraft,referred to as MagicSat,is proposed.Furthermore,the MagicSat system composition,advantages,and application prospects are studied.The enabling technologies and major challenges of MRS are further analyzed in terms of modularization,integrated management,and self-reconfiguration technologies.Finally,the future development trend of MRS technology is predicted,and corresponding suggestions are provided.展开更多
This article, by using mathematical expressions, offers a scientific framework for understanding how the grading system of Qing′s structural carpentry determines the design and construction in the grand style timber...This article, by using mathematical expressions, offers a scientific framework for understanding how the grading system of Qing′s structural carpentry determines the design and construction in the grand style timber architecture.The Qing′s grand style timber structure, which is ready for prefabrication and assembly, is extremely hierarchical oriented and significantly standardized. The general procedure in designing a grand style timber structure is to start with the grade that defines the basic module (dou kou); next comes with the number of bracket set (cuan), the number of longitudinal bays and the number of purlins which affect its plan and cross section; thirdly choose a roof type that determines its longitudinal section and the facade as well. A series of formulae are conducted to help depict the layout, cross sectional roof curvature and special longitudinal treatments in 4 sloped and 9 spined roofs respectively.展开更多
文摘Small modular reactor(SMR)belongs to the research forefront of nuclear reactor technology.Nowadays,advancement of intelligent control technologies paves a new way to the design and build of unmanned SMR.The autonomous control process of SMR can be divided into three stages,say,state diagnosis,autonomous decision-making and coordinated control.In this paper,the autonomous state recognition and task planning of unmanned SMR are investigated.An operating condition recognition method based on the knowledge base of SMR operation is proposed by using the artificial neural network(ANN)technology,which constructs a basis for the state judgment of intelligent reactor control path planning.An improved reinforcement learning path planning algorithm is utilized to implement the path transfer decision-makingThis algorithm performs condition transitions with minimal cost under specified modes.In summary,the full range control path intelligent decision-planning technology of SMR is realized,thus provides some theoretical basis for the design and build of unmanned SMR in the future.
基金Financial support was provided by the State Key Laboratory of Pulp and Paper Engineering(No.2022PY01)the National Natural Science Foundation of China(Nos.22231002 and 21871095)the Key-Area Research and Development Program of Guangdong Province(No.2020B010188001)。
文摘Lignans have been established as a privileged scaffold in drug discovery,particularly in anticancer and antioxidant properties.Concise and efficient construction of lignans and their derivatives in a single operation holds great medicinal significance for structure-activity relationship studies yet remains challenging.Drawing inspiration from the biosynthesis of lignans,we present a general,high-step-economy palladium-catalyzed reaction that converts simple chemical feedstocks into dehydrodibenzylbutyrolactone lignans through the in-situ construction and coupling of two phenylpropanoid molecules.The diversity of organoboronic acids and the editability of enyne provide a powerful platform for the rapid construction of lignan libraries,featuring 82 lignans analogs,collective syntheses of 10 distinct lignan skeletons,and 13 hybrid molecules combining pharmacophore fragments with drug and derivatives.The subtle combination of phosphine ligands with quinones for switching chemoselectivity is vital to the success of this protocol.
基金co-supported by the National Natural Science Foundation of China(No.12372048)the China Postdoctoral Science Foundation(No.2023M742835)+3 种基金the Guangdong Basic and Applied Basic Research Foundation,China(No.2023A1515011421)the Aeronautical Science Foundation of China(No.2022Z004053001)the Fundamental Research Funds for the Central Universities,China(No.D5000210833)the Young Talent Fund of Association for Science and Technology in Shaanxi,China(No.20220509)。
文摘The modular design pattern revolutionizes the monolithic morphology of traditional spacecraft into the reconfigurable combination of modular units.However,due to the morphological changes,the effective takeover control of the combination through multiple independent modules,including the controller and actuator modules,remains a challenge.In this paper,a robust takeover control scheme with high allocation accuracy,independent of precise inertia,is proposed for the reconfigurable combination in the presence of the inertia uncertainty,model parameters uncertainty,communication delay,and external disturbance.By reregulating the conditions for performance synthesis into a symmetric form with similar structure,a hybrid non-fragile H_(2)/H_(∞)controller is designed for handling two types of controller gain perturbations,achieving superior performance with less energy consumption through simultaneous perturbation suppression.Moreover,through temporarily storing the allocation signals in the initial stage to cover the upper bound of the communication delay,the proposed distributed dynamic allocation scheme enables the actuator modules to implement the control signals jointly to stabilize the combination.Distinguished from general allocators,the proposed high-precision allocation scheme under communication delay can not only ensure full exploitation of controller performance,but also dynamically adjust allocation coefficients based on energy consumption index of controller modules to prevent actuator saturation.Numerical simulations demonstrate the superiority of the proposed hybrid non-fragile controller and the allocation scheme.
文摘This paper comprehensively explores the impulsive on-orbit inspection game problem utilizing reinforcement learning and game training methods.The purpose of the spacecraft is to inspect the entire surface of a non-cooperative target with active maneuverability in front lighting.First,the impulsive orbital game problem is formulated as a turn-based sequential game problem.Second,several typical relative orbit transfers are encapsulated into modules to construct a parameterized action space containing discrete modules and continuous parameters,and multi-pass deep Q-networks(MPDQN)algorithm is used to implement autonomous decision-making.Then,a curriculum learning method is used to gradually increase the difficulty of the training scenario.The backtracking proportional self-play training framework is used to enhance the agent’s ability to defeat inconsistent strategies by building a pool of opponents.The behavior variations of the agents during training indicate that the intelligent game system gradually evolves towards an equilibrium situation.The restraint relations between the agents show that the agents steadily improve the strategy.The influence of various factors on game results is tested.
基金funded by the Russian Science Foundation(No.22–49-02047)。
文摘A brief concept study of a modular research aircraft with potential applications to Mars exploration is conducted.Considered are dimensional and mass constraints of a launch vehicle payload compartment,mission radius extension applying ground mobility and overall flight envelope extension using fixed-wing aerodynamics.Also,some lessons learned from NASA Mars Ingenuity flights are considered and addressed with few solutions.The modular system includes a fixed-wing design along with a number of smaller autonomous quadcopter UAVs,encapsulated inside a geodesic spherical support through a gimbal mechanism for ground mobility.Analyzed is the feasibility of allocating to these mini drones both scout and mapping tasks of complex terrain such as crater walls,canyons and cave systems that might hold key insights into the planet's geologic history.Once docked with the mothership fixed wing,the mini drones serve as a distributed propulsion system,for vertical take-off and landing and control,completely replacing control surfaces on the flying wing itself,its engine and landing gear.CFD and structural simulations have demonstrated the flight-ability in Mars conditions of a flying wing design along with scout drone prototypes with a pentagon-hexagon geodesic shell.Also demonstrated is the great flexibility of the suggested modular approach for various research applications and mission profiles on Mars and other planets or moons,improving overall reliability and mission radius.
基金supported by the Dong-A University of the Republic of Korea research fund。
文摘With the increasing demand for secure infrastructure such as hydrogen refueling stations,chemical plants,and energy storage systems,the need for protective structures capable of withstanding close-in detonations has become more critical.Existing design guidelines for protective walls(e.g.,UFC 3-340-02)primarily address mid-and far-field explosions,providing limited insights into near-field effects.Considering the effect of slight slopes(<40°)on reducing maximum reflected overpressure is deemed negligible.This study investigated the effectiveness of a reinforced concrete(RC)modular protection system(MPS)incorpo rating a diagonally tapered wall in attenuating re flected overpressures from closein detonations.Full-scale field experiments using a 51.3 kg TNT charge,representing the explosion energy of a typical hydrogen vessel rupture,demonstrated that a wall with a 7°slope significantly outperformed a vertical wall of equivalent concrete volume in terms of blast resistance.Observed structural responses included cracking,horizontal shear failure,and overturning.Complementary simulations using a validated computational fluid dynamics(CFD)model showed that the tapered wall reduced peak overpressure by 30%-40%compared to an equivalent vertical wall.This result highlights the potential of minor geometric modifications to enhance blast resilience.The tapered design effectively redirects incident blast waves,reducing localized damage while also conserving material,thus preserving modular benefits such as ease of transport and reusability.These findings suggest that diagonally tapered RC-based MPSs can offer a practical and resilient solution for industrial and military applications subject to near-field or sequential blast threats.
基金supported by the Zhejiang Provincial Natural Science Foundation of China(LY22E050011)National Natural Science Foundation of China(T2121004,51805475)。
文摘In clinical practice,the irregular shapes of traumas pose a significant challenge in rapidly manufacturing personalized scaffolds.To address these challenges,inspired by LEGO■ bricks,this study proposed a novel concept of modular scaffolds and developed an innovative system based on machine vision for their rapid and intelligent assembly tailored to defect shapes.Trapezoidal interfaces effectively connect standardized bone units based on magnesium-doped silicate calcium,ensuring high stability of the modular scaffolds,with compressive strength up to 135 MPa and bending strength up to 17 MPa.Through self-developed defect recognition and reconstruction algorithms,defect recognition and personalized assembly schemes for bone scaffolds can be achieved autonomously.Modular scaffolds seamlessly integrate with surrounding bone tissue,promoting new bone growth,with no apparent differences compared to fully 3D printed integral scaffolds in the skull and femur repair experiments.In summary,the adoption of modular scaffolds not only integrates personalization and standardization but also satisfies the optimal treatment window.
文摘Based on the analysis and research of the airworthiness objective of integrated modular avionics system(IMA),and the characteristics of IMA system’s comprehensive and complex cross-linking with other airborne systems,the extraction strategy of IMA system’s compliance flight test subjects and the selection method of IMA system’s compliance flight test parameters are proposed.The data analysis method based on the abnormal probability matrix of the IMA system is proposed for the first time,and the abnormal state information of the IMA system can be quickly identified.The compliance flight test of the IMA system is completed with limited flight test resources,which achieves the purpose of saving flight test sorties and improving flight test efficiency.This research has been successfully applied to the airworthiness certification flight test of a certain civil transport aircraft in China,and can provide technical support for the subsequent type flight test.
文摘Given the rapid growth of sustainable construction strategies globally and the importance of resiliency in civil infrastructure,it is crucial to adopt best practices.Modular construction is one such practice and is considered a better alternative to conventional construction in terms of resilience,construction times,resource efficiency,and sustainability.However,the continued expansion of modular construction relies on quantifying and evaluating its sustainability and the purported benefits.This paper develops and checks feasibility through an integrated multi-level decision support framework to empirically evaluate the sustainability performances of single-family residential modular homes.Criteria and indicator development and calculation,benchmark scale establishment,quantitative and qualitative data collection from literature and surveys,and multi-criteria decision analysis are unique aspects of this framework.The results of the two case studies located in the Okanagan region,Canada showed that modular homes perform at a higher level of sustainability than their conventional counterparts across multiple metrics and levels related to environmental and economic factors.The modular homes scored eco-efficiency values of 62.5 and 56.0,respectively and fell into higher performance range.The proposed frame-work offers flexibility in examining different dimensions of sustainability,providing valuable insights into the key parameters that need to be addressed to enhance overall sustainability.This research,which integrates life cycle thinking and decision-making,helps the construction industry and,municipalities,governments,and pol-icymakers in making informed decisions on the selection of suitable construction methods in city developments and move towards a more resilient and sustainable sector.
基金supported by Technology Research and Development Program of China Construction Advanced Technology Research Institute(Grant No.XJY-2024-16)。
文摘The seismic intensity is generally high in the Qinghai-Tibet Plateau region of China.The seismic performance of the new prefabricated modular pressurized buildings used to solve the plateau response is insufficient.To solve this problem,the small friction pendulum bearing(FPB)isolation design is proposed for modular pressurized buildings.Firstly,a simplified model of cross-truss support for the pressurized module is proposed to simplify the modeling and calculation of the pressurized buildings.The reasonability of the simplified model is verified by comparing the refined finite element model.Subsequently,according to the FPB design process for modular pressurized buildings,a small FPB for isolation is provided for a two-story modular pressurized building under 8-degree fortification earthquakes.Lastly,the seismic effectiveness and constructional feasibility of the isolation structure are verified compared with the non-isolated structure using dynamic time-history analysis.The study results show that the size of FPBs for modular pressurized buildings should consider both displacement and dimension requirements to weigh seismic isolation performance and installation feasibility,respectively.When adopting FPBs,the response of the structure is significantly reduced,and the seismic isolation effect is obvious.The proposed construction process can improve the seismic resilience of the prefabricated modular pressurized buildings by replacing post-earthquake damaged components quickly.It provides ideas for the seismic isolation design of the prefabricated modular pressurized buildings in high seismic intensity areas.
文摘This article focuses on the municipal prefabricated bathroom station.It elaborates on its modular design concept,including key design points such as spatial layout,functional modules,and determination of key parameters;introduces the optimization of intelligent production processes,precision control,and integration of construction technology,and also mentions the verification of full lifecycle applications and quality control;as well as emphasizes the importance of BIM+IoT platform and looks forward to the future.
基金Supported by the National Natural Science Foun-dation of China (60373087)
文摘Modular arithmetic is a fundamental operation and plays an important role in public key cryptosystem. A new method and its theory evidence on the basis of modular arithmetic with large integer modulus-changeable modulus algorithm is proposed to improve the speed of the modular arithmetic in the presented paper. For changeable modulus algorithm, when modular computation of modulo n is difficult, it can be realized by computation of modulo n-1 and n-2 on the perquisite of easy modular computations of modulo n-1 and modulo n-2. The conclusion is that the new method is better than the direct method by computing the modular arithmetic operation with large modulus. Especially, when computations of modulo n-1 and modulo n-2 are easy and computation of modulo n is difficult, this new method will be faster and has more advantages than other algorithms on modular arithmetic. Lastly, it is suggested that the proposed method be applied in public key cryptography based on modular multiplication and modular exponentiation with large integer modulus effectively
基金The National Natural Science Foundation of China(No.60903011)the Natural Science Foundation of Jiangsu Province(No.BK2009267)
文摘A new modular solution to the state explosion problem caused by the Markov-based modular solution of dynamic multiple-phased systems is proposed. First, the solution makes full use of the static parts of dynamic multiple-phased systems and constructs cross-phase dynamic modules by combining the dynamic modules of phase fault trees. Secondly, the system binary decision diagram （BDD） from a modularized multiple- phased system （MPS）is generated by using variable ordering and BDD operations. The computational formulations of the BDD node event probability are derived for various node links and the system reliability results are figured out. Finally, a hypothetical multiple-phased system is given to demonstrate the advantages of the dynamic modular solution when the Markov state space and the size of the system BDD are reduced.
基金supported by the National Defense Science and Technology Innovation Zone of China(No.00205501).
文摘The shape of a spacecraft is transitioning from monolithic,manual,and static to modular,autonomous,and dynamic.Modular Reconfigurable Spacecrafts(MRSs)offer better solutions than traditional monolithic spacecrafts in several aspects,and may become the next generation of spacecraft systems with efficient design,fast deployment,flexible application,and convenient management.This paper reviews the development and technology of MRS from three aspects:Modularity,reconfigurability,and autonomy.Despite the progress of research on MRS,there is still a lack of unified standards and little understanding of related concepts.Based on the understanding of basic concepts,the studies conducted on MRS are reviewed to identify technical requirements and solutions.Aiming at the future development trend of MRS,a novel modular selfreconfigurable spacecraft,referred to as MagicSat,is proposed.Furthermore,the MagicSat system composition,advantages,and application prospects are studied.The enabling technologies and major challenges of MRS are further analyzed in terms of modularization,integrated management,and self-reconfiguration technologies.Finally,the future development trend of MRS technology is predicted,and corresponding suggestions are provided.
文摘This article, by using mathematical expressions, offers a scientific framework for understanding how the grading system of Qing′s structural carpentry determines the design and construction in the grand style timber architecture.The Qing′s grand style timber structure, which is ready for prefabrication and assembly, is extremely hierarchical oriented and significantly standardized. The general procedure in designing a grand style timber structure is to start with the grade that defines the basic module (dou kou); next comes with the number of bracket set (cuan), the number of longitudinal bays and the number of purlins which affect its plan and cross section; thirdly choose a roof type that determines its longitudinal section and the facade as well. A series of formulae are conducted to help depict the layout, cross sectional roof curvature and special longitudinal treatments in 4 sloped and 9 spined roofs respectively.
