A modular system of cascaded converters based on model predictive control(MPC)is proposed to meet the application requirements ofmultiple voltage levels and electrical isolation in renewable energy generation systems....A modular system of cascaded converters based on model predictive control(MPC)is proposed to meet the application requirements ofmultiple voltage levels and electrical isolation in renewable energy generation systems.The system consists of a Buck/Boost+CLLLC cascaded converter as a submodule,which is combined in series and parallel on the input and output sides to achieve direct-current(DC)voltage transformation,bidirectional energy flow,and electrical isolation.The CLLLC converter operates in DC transformer mode in the submodule,while the Buck/Boost converter participates in voltage regulation.This article establishes a suitable mathematical model for the proposed system topology,and uses MPC to control the system based on this mathematical model.Module parameters are designed and calculated,and simulation is built in MATLAB/Simulink to complete the simulation comparison experiment between MPC and traditional proportional integral(PI)control.Finally,a physical experimental platform is built to complete the physical comparison experiment.The simulation and physical experimental results prove that the control accuracy and response speed ofMPC are better than traditional PI control strategy.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
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
Distributed Integrated Modular Avionics(DIMA)develops from Integrated Modular Avionics(IMA)and realizes distributed integration of multiple sub-function areas.Timetriggered network provides effective support for time ...Distributed Integrated Modular Avionics(DIMA)develops from Integrated Modular Avionics(IMA)and realizes distributed integration of multiple sub-function areas.Timetriggered network provides effective support for time synchronization and information coordination in DIMA systems.However,inconsistency between processing resources and communication network destroys the time determinism benefiting from partitions and time-triggered mechanism.To ensure such time determinism and achieve guaranteed real-time performance,system design should collectively provide a global communication scheme for messages in network domain and a corresponding execution scheme for partitions in processing domain.This paper firstly establishes a general DIMA model which coordinates partitioned processing and time-triggered communication,and then proposes a hybrid scheduling algorithm using Mixed Integer Programming to produce feasible system schemes.Furthermore,incrementally integrating new functions causes upgrades or reconfigurations of DIMA systems and will generate integration cost.To control such cost,this paper further develops an optimization algorithm based on Maximum Satisfiability Problem and guarantees that the scheduling design for upgraded DIMA systems inherit their original schemes as much as possible.Finally,two typical cases,including a simple fully connected DIMA system case and an industrial DIMA system case,are constructed to illustrate our DIMA model and validate the effectiveness of our hybrid scheduling algorithms.展开更多
Recently the integrated modular avionics （IMA） architecture which introduces the concept of resource partitioning becomes popular as an alternative to the traditional federated architecture. A novel hierarchical app...Recently the integrated modular avionics （IMA） architecture which introduces the concept of resource partitioning becomes popular as an alternative to the traditional federated architecture. A novel hierarchical approach is proposed to solve the resource allocation problem for IMA systems in distributed environments. Firstly, the worst case response time of tasks with arbitrary deadlines is analyzed for the two-level scheduler. Then, the hierarchical resource allocation approach is presented in two levels. At the platform level, a task assignment algorithm based on genetic simulated annealing （GSA） is proposed to assign a set of pre-defined tasks to different processing nodes in the form of task groups, so that resources can be allocated as partitions and mapped to task groups. While yielding to all the resource con- straints, the algorithm tries to find an optimal task assignment with minimized communication costs and balanced work load. At the node level, partition parameters are optimized, so that the computational resource can be allocated further. An example is shown to illustrate the hierarchal resource allocation approach and manifest the validity. Simulation results comparing the performance of the proposed GSA with that of traditional genetic algorithms are presented in the context of task assignment in IMA systems.展开更多
The intricate interplay between rock mechanics and fracture-induced fluid flow during resource extrac-tion exerts profound effects on groundwater systems,posing a pivotal challenge for promoting green and safe develop...The intricate interplay between rock mechanics and fracture-induced fluid flow during resource extrac-tion exerts profound effects on groundwater systems,posing a pivotal challenge for promoting green and safe development in underground engineering.To address this,a novel numerical model with an explicit coupling simulation strategy is presented.This model integrates distinct modules for individual physical mechanisms,ensuring second-order accuracy through shared time integration,thereby overcoming lim-itations in simulating mining-induced strata damage,water flow,and permeability dynamics.A novel mathematical model is incorporated into the mechanical simulation to characterize the abrupt increase in permeability resulting from rock fracture propagation.This increase is quantified by evaluating the plastic damage state of rocks and incorporating a damage coefficient that is intrinsically linked to rock strength.The mechanical model tracks permeability changes due to mining.The flow model simulates aquifer-mine water interactions by calculating hydraulic conductivity and using dynamic zoning,adapt-ing to mining progress.When applied to a case study of a complex mine,this approach significantly improved the accuracy of water inflow rate predictions by 57%.展开更多
4-Bromo-3-methylanisole is mainly used to synthesize black fluorane dye(2-anilino-3-methyl-6-dibutylaminofluorane, ODB-2), which is one of the most important heat and pressure-sensitive dyes in the manufacture of ther...4-Bromo-3-methylanisole is mainly used to synthesize black fluorane dye(2-anilino-3-methyl-6-dibutylaminofluorane, ODB-2), which is one of the most important heat and pressure-sensitive dyes in the manufacture of thermal papers. Compared to the industrial heterogeneous batch process, a continuous homogeneous bromination technology in a modular microreaction system has been developed, and 4-bromo-3-methylanisole has been successfully prepared through high-selective mono-bromination of 3-methylanisole with Br2 solution in CHCl3. In optimal conditions, the content of bis-brominated byproducts can be controlled less than 0.5%,which is superior to the industrial standard with 99.5% 3-methylanisole conversion at very short residence time and mild reaction temperature.展开更多
Modeling of a centrifugal compressor is of great significance to surge characteristics and fluid dynamics in the Altitude Ground Test Facilities(AGTF).Real-time Modular Dynamic System Greitzer(MDSG)modeling for dynami...Modeling of a centrifugal compressor is of great significance to surge characteristics and fluid dynamics in the Altitude Ground Test Facilities(AGTF).Real-time Modular Dynamic System Greitzer(MDSG)modeling for dynamic response and simulation of the compression system is introduced.The centrifugal compressor,pipeline network,and valve are divided into pressure output type and mass flow output type for module modeling,and the two types of components alternate when the system is established.The pressure loss and thermodynamics of the system are considered.An air supply compression system of AGTF is modeled and simulated by the MDSG model.The simulation results of mass flow,pressure,and temperature are compared with the experimental results,and the error is less than 5%,which demonstrates the reliability,practicability,and universality of the MDSG model.展开更多
Objective:To investigate the efficacy and patient satisfaction of the EarWell Infant Ear Correction System combined with modular parents'nursing education's curative effect on deformed auricle.Methods:A total ...Objective:To investigate the efficacy and patient satisfaction of the EarWell Infant Ear Correction System combined with modular parents'nursing education's curative effect on deformed auricle.Methods:A total of 42 patients(29 boys and 13 girls;73 ears;age≤3 months)with auricle deformities who had received EarWell Infant Ear Correction System's treatment and modular parents'nursing education in Guangzhou Children and Women's Medical Center between April and October 2018.The modular parents'education program is standardized by EarWell system.Physician and patients'parents compared the severity of auricle deformity separately before and after the treatment by using the auricle deformities visual analogue scales(VAS)rating system.Patient satisfaction was evaluated by using global aesthetic improvement scale(GAIS).The data collected of auricle deformities VAS and GAIS satisfaction score were applied to measure the treatment's effectiveness.Results:All the 42 patients(73 external ears)completed the treatment with EarWell Infant Ear Correction System and modular parents'nursing education.The mean age at initiation of treatment was 37.87±19.44 days and the therapeutic time span was 47.21±17.36 days.At the end of treatment,the physician's and patients'guardians rating of the severity of auricle deformity were significantly improved separately compared to the initial rating(8.33±1.27 vs.6.51±0.84;P<0.005)(5.77±1.59 vs.8.19±2.38 P<0.05).During the treatment and parents'home nursing care period,the side effect and complications were minor like skin eczema and irrigation;there were no severe complications such as necrosis of the skin and cartilage.The patient tolerance for the treatment was acceptable with the adequate parents'nursing care.Most patients'guardians were satisfied with the treatment outcomes of EarWell Infant Ear Correction System with more engagement of nursing care,the GAIS's rating were increased from pretreatment stage's 26.19%to treatment completed stage's 90.48%,and the difference was statistically significant(P<0.05).Conclusions:In this study,we proved that EarWell Infant Ear Correction System with its unique parents'modular nursing care education,as a noninvasive treatment,reasonably improved auricle morphological malformation,and patients'guardians satisfaction with few complications,which is worthy of a wildly clinical promotion.展开更多
Integrating wave energy converters(WECs)with offshore platforms offers numerous advantages,such as reducing wave loads,supplying energy to the platform,and cost-sharing in construction.This paper reports an experiment...Integrating wave energy converters(WECs)with offshore platforms offers numerous advantages,such as reducing wave loads,supplying energy to the platform,and cost-sharing in construction.This paper reports an experimental investigation focusing on the hydrodynamic characteristics of a proposed modular floating structure system integrated with WEC-type floating artificial reefs.The proposed system comprises several serially arranged hexagonal floating structures,anchored by tension legs,and integrated with outermost WEC-type floating artificial reefs.A simplified wave energy converter utilizing the relative pitch motion between adjacent modules for energy conversion was constructed in the scale model test.The effects of chain-type modular expansion on the multi-body motion response,mooring tension response,and WEC performance of the system have been thoroughly investigated.The experimental results indicate that increasing the number of hexagonal modules can notably reduce the system’s surge response,particularly under survival sea conditions.The connection of the outermost reef modules slightly increases the tension leg load of the adjacent module,whereas the tension leg load remains relatively consistent across the inner hexagonal modules.Furthermore,through a comparison of the dynamic responses of the hexagonal module connected and unconnected outermost reefs,the good performance in terms of energy conversion and wave attenuation of the WECtype floating artificial reef modules was effectively validated.The main results from this work can provide useful references for engineering applications involving modular floating structures integrated with WECs.展开更多
To solve the existing problems during the ceramic mold enterprises product design and development process, the variable structure parametric design system based on modular of ceramic mold has been developed. The syste...To solve the existing problems during the ceramic mold enterprises product design and development process, the variable structure parametric design system based on modular of ceramic mold has been developed. The system uses the object-oriented technology and top-down design concept as a guide, establishes a ceramic mold parametric design process, divides the process of ceramic mold design into modules of different levels and creates a component model library based on the functional analysis. Expanding modular thinking to parts structure design level is an effective solution to the difficulty of changing the structure during the product design process. Examples show that the system can achieve a ceramic mold product design, improve design efficiency.展开更多
This paper studies a fault-tolerant control system for a space modular manipulator system mounted on space station or other spacecrafts such as satellites, located in low earth orbit. Design technologies for tradition...This paper studies a fault-tolerant control system for a space modular manipulator system mounted on space station or other spacecrafts such as satellites, located in low earth orbit. Design technologies for traditional industrial manipulator systems cannot be directly used to the space ones due to the special space environment and compactness. Considering the extremely tight constraints on mass, power consumption, volume, cost and ＂design-to-orbit＂ schedules, the fault-tolerant control system is developed mainly based on commercial-off-the-shaft components. The features of the hardware and software of the fault-tolerant control system are presented. The performance specifications are also discussed. Because many space proven design technologies and experiences are adopted, the fault-tolerant control system is characterized by high reliability and practicability.展开更多
Modularized circuit designs for chaotic systems are introduced in this paper.Especially,a typical improved modularized design strategy is proposed and applied to a new hyper-chaotic system circuit implementation.In th...Modularized circuit designs for chaotic systems are introduced in this paper.Especially,a typical improved modularized design strategy is proposed and applied to a new hyper-chaotic system circuit implementation.In this paper,the detailed design procedures are described.Multisim simulations and physical experiments are conducted,and the simulation results are compared with Matlab simulation results for different system parameter pairs.These results are consistent with each other and they verify the existence of the hyper-chaotic attractor for this new hyper-chaotic system.展开更多
The implementation of multiple enzymes for chemical production in a cell‐free scenario is an emerging field in biomanufacturing.It enables the redesign and reconstitution of new enzymatic routes for producing chemica...The implementation of multiple enzymes for chemical production in a cell‐free scenario is an emerging field in biomanufacturing.It enables the redesign and reconstitution of new enzymatic routes for producing chemicals that may be hard to obtain from natural pathways.Although the construction of a cell‐free multienzyme system is highly flexible and adaptable,it is challenging to make all enzymatic reactions act in concert.Recently,modular construction has been conceptual‐ized as an effective way to harmonize diverse enzymatic reactions.In this review,we introduce the concept of a multienzyme module and exemplify representative modules found in Nature.We then categorize recent developments of synthetic multienzyme modules into main‐reaction modules and auxiliary modules according to their roles in reaction routes.We highlight four main‐reaction mod‐ules that can perform carbon metabolism,carbon assimilation,protein glycosylation and nonribo‐somal peptide synthesis,and exemplify auxiliary modules used for energy supply,protection and reinforcement for main reactions.The reactor‐level modularization of multienzyme catalysis is also discussed.展开更多
Modular unit systems provide an eco-friendly advanced construction method that improves productivity and reduces carbon emissions and construction waste. In these systems, the prefabrication ratio of the modules shoul...Modular unit systems provide an eco-friendly advanced construction method that improves productivity and reduces carbon emissions and construction waste. In these systems, the prefabrication ratio of the modules should be high in order to support these eco-friendly features. The purpose of this study was to verify the functionality and driving safety of fixing a modular unit with a high prefabrication ratio to a vehicle for transportation to the site using two novel adapter blocks specially developed for this purpose. When asked to evaluate their performance for this study, the truck drivers selected adaptor block type B as providing the highest convenience and functionality. In real-world driving experiments, maximum loads of 15 kN and 25 kN were measured on adapter block types A and B, respectively. Future improvements in the adapter blocks that take the safety ratio and the improved convenience of use into account are confidently expected to contribute to the eco-friendliness and the improved productivity of modular unit systems.展开更多
The present work reports a Hybrid Modular Floating Structure(HMFS)system with typical malfunction conditions.The effects of both fractured mooring lines and failed connectors on main hydrodynamic responses(mooring lin...The present work reports a Hybrid Modular Floating Structure(HMFS)system with typical malfunction conditions.The effects of both fractured mooring lines and failed connectors on main hydrodynamic responses(mooring line tensions,module motions,connector loads and wave power production)of the HMFS system under typical sea con-ditions are comparatively investigated.The results indicate that the mooring tension distribution,certain module motions(surge,sway and yaw)and connector loads(Mz)are significantly influenced by mooring line fractures.The adjacent mooring line of the fractured line on the upstream side suffers the largest tension among the remaining mooring lines,and the case with two fractured mooring lines in the same group on the upstream side is the most dangerous among all cases of two-line failures in view of mooring line tensions,module motions and connector loads.There-fore,one emergency strategy with appropriate relaxation of a proper mooring line has been proposed and proved effective to reduce the risk of more progressive mooring line fractures.In addition,connector failures substantially affect certain module motions(heave and pitch),certain connector loads(Fz and My)and wave power production.The present work can be helpful and instructive for studies on malfunction conditions of modular floating structure(MFS)systems.展开更多
A self-reconfigurable robot is a non-linear complex system composed of a large number of modules. The complexity caused by non-linearity makes it difficult to solve the problem of module motion planning and shape-chan...A self-reconfigurable robot is a non-linear complex system composed of a large number of modules. The complexity caused by non-linearity makes it difficult to solve the problem of module motion planning and shape-changing control with the traditional algorithm. In this paper, a full-discrete metamorphic algorithm is proposed. The modules concurrently process the local sensing information, update their eigenvector, and act by the same predetermined logical rules. Then a reasonable motion sequence for modules and the global metamorphosis can be obtained. Therefore, the complexity of metamorphic algorithm is reduced, the metamorphic procedure is simplified, and the self-organizing metamorphosis can be obtained. The algorithm cases of several typical systems are studied and evaluated through simulation program of 2-D planar homogeneous modular systems.展开更多
The stop control strategy of modular multilevel converter based HVDC transmission system is proposed. This stop process is divided into stages of energy feedback and energy consumption. The DC voltage controller is co...The stop control strategy of modular multilevel converter based HVDC transmission system is proposed. This stop process is divided into stages of energy feedback and energy consumption. The DC voltage controller is coordinated to the used modules per phase when active power is transmitted prior to reactive power, so that the energy is fed back to the AC power grid connected to the converter station which uses the fixed dc voltage controller. In addition, in view of the different forms connected to the grid, specifically when the converter station supplies power for passive network, the passive converter station can take a certain auxiliary trigger strategy to make its maximum energy feedback to the grid. Finally, a simulation system of the MMC-HVDC system is constructed in Matlab/Simulink environment, and simulation results show that the proposed stop strategies are effective.展开更多
基金supported by the National Key Research and Development Plan,Grant/Award Number:2018YFB1503005.
文摘A modular system of cascaded converters based on model predictive control(MPC)is proposed to meet the application requirements ofmultiple voltage levels and electrical isolation in renewable energy generation systems.The system consists of a Buck/Boost+CLLLC cascaded converter as a submodule,which is combined in series and parallel on the input and output sides to achieve direct-current(DC)voltage transformation,bidirectional energy flow,and electrical isolation.The CLLLC converter operates in DC transformer mode in the submodule,while the Buck/Boost converter participates in voltage regulation.This article establishes a suitable mathematical model for the proposed system topology,and uses MPC to control the system based on this mathematical model.Module parameters are designed and calculated,and simulation is built in MATLAB/Simulink to complete the simulation comparison experiment between MPC and traditional proportional integral(PI)control.Finally,a physical experimental platform is built to complete the physical comparison experiment.The simulation and physical experimental results prove that the control accuracy and response speed ofMPC are better than traditional PI control strategy.
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.
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co-supported by the National Natural Science Foundation of China(No.71701020)the Defense Research Field Foundation of China(No.61403120404)the Civil Aircraft Airworthiness and Maintenance Key Laboratory Fund of Civil Aviation University of China(No.2017SW02).
文摘Distributed Integrated Modular Avionics(DIMA)develops from Integrated Modular Avionics(IMA)and realizes distributed integration of multiple sub-function areas.Timetriggered network provides effective support for time synchronization and information coordination in DIMA systems.However,inconsistency between processing resources and communication network destroys the time determinism benefiting from partitions and time-triggered mechanism.To ensure such time determinism and achieve guaranteed real-time performance,system design should collectively provide a global communication scheme for messages in network domain and a corresponding execution scheme for partitions in processing domain.This paper firstly establishes a general DIMA model which coordinates partitioned processing and time-triggered communication,and then proposes a hybrid scheduling algorithm using Mixed Integer Programming to produce feasible system schemes.Furthermore,incrementally integrating new functions causes upgrades or reconfigurations of DIMA systems and will generate integration cost.To control such cost,this paper further develops an optimization algorithm based on Maximum Satisfiability Problem and guarantees that the scheduling design for upgraded DIMA systems inherit their original schemes as much as possible.Finally,two typical cases,including a simple fully connected DIMA system case and an industrial DIMA system case,are constructed to illustrate our DIMA model and validate the effectiveness of our hybrid scheduling algorithms.
基金supported by the National Natural Science Foundation of China (60879024)
文摘Recently the integrated modular avionics （IMA） architecture which introduces the concept of resource partitioning becomes popular as an alternative to the traditional federated architecture. A novel hierarchical approach is proposed to solve the resource allocation problem for IMA systems in distributed environments. Firstly, the worst case response time of tasks with arbitrary deadlines is analyzed for the two-level scheduler. Then, the hierarchical resource allocation approach is presented in two levels. At the platform level, a task assignment algorithm based on genetic simulated annealing （GSA） is proposed to assign a set of pre-defined tasks to different processing nodes in the form of task groups, so that resources can be allocated as partitions and mapped to task groups. While yielding to all the resource con- straints, the algorithm tries to find an optimal task assignment with minimized communication costs and balanced work load. At the node level, partition parameters are optimized, so that the computational resource can be allocated further. An example is shown to illustrate the hierarchal resource allocation approach and manifest the validity. Simulation results comparing the performance of the proposed GSA with that of traditional genetic algorithms are presented in the context of task assignment in IMA systems.
基金supported by the National Natural Science Foundation of China (Nos. 42027801, 42072284, and 42372297)the National Key Research and Development Program of China (Nos. 2023YFC3012102 and 2021YFC2902004)the Fundamental Research Funds for the Central Universities (No. 2023ZKPYSH01)
文摘The intricate interplay between rock mechanics and fracture-induced fluid flow during resource extrac-tion exerts profound effects on groundwater systems,posing a pivotal challenge for promoting green and safe development in underground engineering.To address this,a novel numerical model with an explicit coupling simulation strategy is presented.This model integrates distinct modules for individual physical mechanisms,ensuring second-order accuracy through shared time integration,thereby overcoming lim-itations in simulating mining-induced strata damage,water flow,and permeability dynamics.A novel mathematical model is incorporated into the mechanical simulation to characterize the abrupt increase in permeability resulting from rock fracture propagation.This increase is quantified by evaluating the plastic damage state of rocks and incorporating a damage coefficient that is intrinsically linked to rock strength.The mechanical model tracks permeability changes due to mining.The flow model simulates aquifer-mine water interactions by calculating hydraulic conductivity and using dynamic zoning,adapt-ing to mining progress.When applied to a case study of a complex mine,this approach significantly improved the accuracy of water inflow rate predictions by 57%.
基金financial support from National Key R&D Program of China(2017YFB0307102)National Natural Science Foundation of China(21991100,21991104)。
文摘4-Bromo-3-methylanisole is mainly used to synthesize black fluorane dye(2-anilino-3-methyl-6-dibutylaminofluorane, ODB-2), which is one of the most important heat and pressure-sensitive dyes in the manufacture of thermal papers. Compared to the industrial heterogeneous batch process, a continuous homogeneous bromination technology in a modular microreaction system has been developed, and 4-bromo-3-methylanisole has been successfully prepared through high-selective mono-bromination of 3-methylanisole with Br2 solution in CHCl3. In optimal conditions, the content of bis-brominated byproducts can be controlled less than 0.5%,which is superior to the industrial standard with 99.5% 3-methylanisole conversion at very short residence time and mild reaction temperature.
基金supported in part by the Stable Support Research Project of AECC Sichuan Gas Turbine Establishment,China(No.GJCZ-0013-19)the Open Foundation of State Key Laboratory of Compressor Technology,China(Compressor Technology Laboratory of Anhui Province)(No.SKL-YSJ2020007).
文摘Modeling of a centrifugal compressor is of great significance to surge characteristics and fluid dynamics in the Altitude Ground Test Facilities(AGTF).Real-time Modular Dynamic System Greitzer(MDSG)modeling for dynamic response and simulation of the compression system is introduced.The centrifugal compressor,pipeline network,and valve are divided into pressure output type and mass flow output type for module modeling,and the two types of components alternate when the system is established.The pressure loss and thermodynamics of the system are considered.An air supply compression system of AGTF is modeled and simulated by the MDSG model.The simulation results of mass flow,pressure,and temperature are compared with the experimental results,and the error is less than 5%,which demonstrates the reliability,practicability,and universality of the MDSG model.
文摘Objective:To investigate the efficacy and patient satisfaction of the EarWell Infant Ear Correction System combined with modular parents'nursing education's curative effect on deformed auricle.Methods:A total of 42 patients(29 boys and 13 girls;73 ears;age≤3 months)with auricle deformities who had received EarWell Infant Ear Correction System's treatment and modular parents'nursing education in Guangzhou Children and Women's Medical Center between April and October 2018.The modular parents'education program is standardized by EarWell system.Physician and patients'parents compared the severity of auricle deformity separately before and after the treatment by using the auricle deformities visual analogue scales(VAS)rating system.Patient satisfaction was evaluated by using global aesthetic improvement scale(GAIS).The data collected of auricle deformities VAS and GAIS satisfaction score were applied to measure the treatment's effectiveness.Results:All the 42 patients(73 external ears)completed the treatment with EarWell Infant Ear Correction System and modular parents'nursing education.The mean age at initiation of treatment was 37.87±19.44 days and the therapeutic time span was 47.21±17.36 days.At the end of treatment,the physician's and patients'guardians rating of the severity of auricle deformity were significantly improved separately compared to the initial rating(8.33±1.27 vs.6.51±0.84;P<0.005)(5.77±1.59 vs.8.19±2.38 P<0.05).During the treatment and parents'home nursing care period,the side effect and complications were minor like skin eczema and irrigation;there were no severe complications such as necrosis of the skin and cartilage.The patient tolerance for the treatment was acceptable with the adequate parents'nursing care.Most patients'guardians were satisfied with the treatment outcomes of EarWell Infant Ear Correction System with more engagement of nursing care,the GAIS's rating were increased from pretreatment stage's 26.19%to treatment completed stage's 90.48%,and the difference was statistically significant(P<0.05).Conclusions:In this study,we proved that EarWell Infant Ear Correction System with its unique parents'modular nursing care education,as a noninvasive treatment,reasonably improved auricle morphological malformation,and patients'guardians satisfaction with few complications,which is worthy of a wildly clinical promotion.
基金financially supported by the National Natural Science Foundation of China(Grant No.52161041)the Natural Science Foundation of Hainan Province(Grant No.520RC552).
文摘Integrating wave energy converters(WECs)with offshore platforms offers numerous advantages,such as reducing wave loads,supplying energy to the platform,and cost-sharing in construction.This paper reports an experimental investigation focusing on the hydrodynamic characteristics of a proposed modular floating structure system integrated with WEC-type floating artificial reefs.The proposed system comprises several serially arranged hexagonal floating structures,anchored by tension legs,and integrated with outermost WEC-type floating artificial reefs.A simplified wave energy converter utilizing the relative pitch motion between adjacent modules for energy conversion was constructed in the scale model test.The effects of chain-type modular expansion on the multi-body motion response,mooring tension response,and WEC performance of the system have been thoroughly investigated.The experimental results indicate that increasing the number of hexagonal modules can notably reduce the system’s surge response,particularly under survival sea conditions.The connection of the outermost reef modules slightly increases the tension leg load of the adjacent module,whereas the tension leg load remains relatively consistent across the inner hexagonal modules.Furthermore,through a comparison of the dynamic responses of the hexagonal module connected and unconnected outermost reefs,the good performance in terms of energy conversion and wave attenuation of the WECtype floating artificial reef modules was effectively validated.The main results from this work can provide useful references for engineering applications involving modular floating structures integrated with WECs.
文摘To solve the existing problems during the ceramic mold enterprises product design and development process, the variable structure parametric design system based on modular of ceramic mold has been developed. The system uses the object-oriented technology and top-down design concept as a guide, establishes a ceramic mold parametric design process, divides the process of ceramic mold design into modules of different levels and creates a component model library based on the functional analysis. Expanding modular thinking to parts structure design level is an effective solution to the difficulty of changing the structure during the product design process. Examples show that the system can achieve a ceramic mold product design, improve design efficiency.
基金"863" National High Technology Foundation in Astronautics(2005AA742030)
文摘This paper studies a fault-tolerant control system for a space modular manipulator system mounted on space station or other spacecrafts such as satellites, located in low earth orbit. Design technologies for traditional industrial manipulator systems cannot be directly used to the space ones due to the special space environment and compactness. Considering the extremely tight constraints on mass, power consumption, volume, cost and ＂design-to-orbit＂ schedules, the fault-tolerant control system is developed mainly based on commercial-off-the-shaft components. The features of the hardware and software of the fault-tolerant control system are presented. The performance specifications are also discussed. Because many space proven design technologies and experiences are adopted, the fault-tolerant control system is characterized by high reliability and practicability.
基金supported by the Young Scientists Fund of the National Natural Science Foundation of China(Grant No.61403395)the Natural Science Foundation of Tianjin,China(Grant No.13JCYBJC39000)+3 种基金the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry of Chinathe Fund from the Tianjin Key Laboratory of Civil Aircraft Airworthiness and Maintenance in Civil Aviation of China(Grant No.104003020106)the National Basic Research Program of China(Grant No.2014CB744904)the Fund for the Scholars of Civil Aviation University of China(Grant No.2012QD21x)
文摘Modularized circuit designs for chaotic systems are introduced in this paper.Especially,a typical improved modularized design strategy is proposed and applied to a new hyper-chaotic system circuit implementation.In this paper,the detailed design procedures are described.Multisim simulations and physical experiments are conducted,and the simulation results are compared with Matlab simulation results for different system parameter pairs.These results are consistent with each other and they verify the existence of the hyper-chaotic attractor for this new hyper-chaotic system.
文摘The implementation of multiple enzymes for chemical production in a cell‐free scenario is an emerging field in biomanufacturing.It enables the redesign and reconstitution of new enzymatic routes for producing chemicals that may be hard to obtain from natural pathways.Although the construction of a cell‐free multienzyme system is highly flexible and adaptable,it is challenging to make all enzymatic reactions act in concert.Recently,modular construction has been conceptual‐ized as an effective way to harmonize diverse enzymatic reactions.In this review,we introduce the concept of a multienzyme module and exemplify representative modules found in Nature.We then categorize recent developments of synthetic multienzyme modules into main‐reaction modules and auxiliary modules according to their roles in reaction routes.We highlight four main‐reaction mod‐ules that can perform carbon metabolism,carbon assimilation,protein glycosylation and nonribo‐somal peptide synthesis,and exemplify auxiliary modules used for energy supply,protection and reinforcement for main reactions.The reactor‐level modularization of multienzyme catalysis is also discussed.
文摘Modular unit systems provide an eco-friendly advanced construction method that improves productivity and reduces carbon emissions and construction waste. In these systems, the prefabrication ratio of the modules should be high in order to support these eco-friendly features. The purpose of this study was to verify the functionality and driving safety of fixing a modular unit with a high prefabrication ratio to a vehicle for transportation to the site using two novel adapter blocks specially developed for this purpose. When asked to evaluate their performance for this study, the truck drivers selected adaptor block type B as providing the highest convenience and functionality. In real-world driving experiments, maximum loads of 15 kN and 25 kN were measured on adapter block types A and B, respectively. Future improvements in the adapter blocks that take the safety ratio and the improved convenience of use into account are confidently expected to contribute to the eco-friendliness and the improved productivity of modular unit systems.
基金supported by Shenzhen Science and Technology Program(Grant No.KQTD20210811090112003)the National Natural Science Foundation of China(Grant No.52161041).
文摘The present work reports a Hybrid Modular Floating Structure(HMFS)system with typical malfunction conditions.The effects of both fractured mooring lines and failed connectors on main hydrodynamic responses(mooring line tensions,module motions,connector loads and wave power production)of the HMFS system under typical sea con-ditions are comparatively investigated.The results indicate that the mooring tension distribution,certain module motions(surge,sway and yaw)and connector loads(Mz)are significantly influenced by mooring line fractures.The adjacent mooring line of the fractured line on the upstream side suffers the largest tension among the remaining mooring lines,and the case with two fractured mooring lines in the same group on the upstream side is the most dangerous among all cases of two-line failures in view of mooring line tensions,module motions and connector loads.There-fore,one emergency strategy with appropriate relaxation of a proper mooring line has been proposed and proved effective to reduce the risk of more progressive mooring line fractures.In addition,connector failures substantially affect certain module motions(heave and pitch),certain connector loads(Fz and My)and wave power production.The present work can be helpful and instructive for studies on malfunction conditions of modular floating structure(MFS)systems.
文摘A self-reconfigurable robot is a non-linear complex system composed of a large number of modules. The complexity caused by non-linearity makes it difficult to solve the problem of module motion planning and shape-changing control with the traditional algorithm. In this paper, a full-discrete metamorphic algorithm is proposed. The modules concurrently process the local sensing information, update their eigenvector, and act by the same predetermined logical rules. Then a reasonable motion sequence for modules and the global metamorphosis can be obtained. Therefore, the complexity of metamorphic algorithm is reduced, the metamorphic procedure is simplified, and the self-organizing metamorphosis can be obtained. The algorithm cases of several typical systems are studied and evaluated through simulation program of 2-D planar homogeneous modular systems.
文摘The stop control strategy of modular multilevel converter based HVDC transmission system is proposed. This stop process is divided into stages of energy feedback and energy consumption. The DC voltage controller is coordinated to the used modules per phase when active power is transmitted prior to reactive power, so that the energy is fed back to the AC power grid connected to the converter station which uses the fixed dc voltage controller. In addition, in view of the different forms connected to the grid, specifically when the converter station supplies power for passive network, the passive converter station can take a certain auxiliary trigger strategy to make its maximum energy feedback to the grid. Finally, a simulation system of the MMC-HVDC system is constructed in Matlab/Simulink environment, and simulation results show that the proposed stop strategies are effective.
