This paper presented a novel tinny motion capture system for measuring bird posture based on inertial and magnetic measurement units that are made up of micromachined gyroscopes, accelerometers, and magnetometers. Mul...This paper presented a novel tinny motion capture system for measuring bird posture based on inertial and magnetic measurement units that are made up of micromachined gyroscopes, accelerometers, and magnetometers. Multiple quaternion-based extended Kalman filters were implemented to estimate the absolute orientations to achieve high accuracy.Under the guidance of ornithology experts, the extending/contracting motions and flapping cycles were recorded using the developed motion capture system, and the orientation of each bone was also analyzed. The captured flapping gesture of the Falco peregrinus is crucial to the motion database of raptors as well as the bionic design.展开更多
This study presents a kinematic calibration method for exoskeletal inertial motion capture (EI-MoCap) system with considering the random colored noise such as gyroscopic drift.In this method, the geometric parameters ...This study presents a kinematic calibration method for exoskeletal inertial motion capture (EI-MoCap) system with considering the random colored noise such as gyroscopic drift.In this method, the geometric parameters are calibrated by the traditional calibration method at first. Then, in order to calibrate the parameters affected by the random colored noise, the expectation maximization (EM) algorithm is introduced. Through the use of geometric parameters calibrated by the traditional calibration method, the iterations under the EM framework are decreased and the efficiency of the proposed method on embedded system is improved. The performance of the proposed kinematic calibration method is compared to the traditional calibration method. Furthermore, the feasibility of the proposed method is verified on the EI-MoCap system. The simulation and experiment demonstrate that the motion capture precision is significantly improved by 16.79%and 7.16%respectively in comparison to the traditional calibration method.展开更多
Metal-Organic Frameworks(MOFs)have been developed as solid sorbents for CO_(2) capture applications and their properties can be controlled by tuning the chemical blocks of their crystalline units.A number of MOFs(e.g....Metal-Organic Frameworks(MOFs)have been developed as solid sorbents for CO_(2) capture applications and their properties can be controlled by tuning the chemical blocks of their crystalline units.A number of MOFs(e.g.,HKUST-1)have been developed but the question remains how to deploy them for gas-solid contact.Unfortunately,the direct use of MOFs as nanocrystals would lead to serious problems and risks.Here,for the first time,we report a novel MOF-based hybrid sorbent that is produced via an innovative in-situ microencapsulated synthesis.Using a custom-made double capillary microfluidic assembly,double emulsions of the MOF precursor solutions and UV-curable silicone shell fluid are produced.Subsequently,HKUST-1 MOF is successfully synthesized within the droplets enclosed in the gas permeable microcapsules.The developed MOF-bearing microcapsules uniquely allow the deployment of functional nanocrystals without the challenge of handling ultrafine particles,and further,can selectively reject undesired compounds to protect encapsulated MOFs.展开更多
Temperature-swing adsorption(TSA)is an effective technique for CO_(2) capture,but the temperature swing procedure is energy-intensive.Herein,we report a low-energy-consumption system by combining passive radiative coo...Temperature-swing adsorption(TSA)is an effective technique for CO_(2) capture,but the temperature swing procedure is energy-intensive.Herein,we report a low-energy-consumption system by combining passive radiative cooling and solar heating for the uptake of CO_(2) on commercial activated carbons(CACs).During adsorption,the adsorbents are coated with a layer of hierarchically porous poly(vinylidene fluoride-co-hexafluoropropene)[P(VdF-HFP)HP],which cools the adsorbents to a low temperature under sunlight through radiative cooling.For desorption,CACs with broad absorption of the solar spectrum are exposed to light irradiation for heating.The heating and cooling processes are completely driven by solar energy.Adsorption tests under mimicked sunlight using the CACs show that the performance of this system is comparable to that of the traditional ones.Furthermore,under real sunlight irradiation,the adsorption capacity of the CACs can be well maintained after multiple cycles.The present work may inspire the development of new temperature swing procedures with little energy consumption.展开更多
Background:The development of computer vision technology has enabled the use of markerless movement tracking for biomechanical analysis.Recent research has reported the feasibility of markerless systems in motion anal...Background:The development of computer vision technology has enabled the use of markerless movement tracking for biomechanical analysis.Recent research has reported the feasibility of markerless systems in motion analysis but has yet to fully explore their utility for capturing faster movements,such as running.Applied studies using markerless systems in clinical and sports settings are still lacking.Thus,the present study compared running biomechanics estimated by marker-based and markerless systems.Given running speed not only affects sports performance but is also associated with clinical injury prevention,diagnosis,and rehabilitation,we aimed to investigate the effects of speed on the comparison of estimated lower extremity joint moments and powers between markerless and marker-based technologies during treadmill running as a concurrent validating study.Methods:Kinematic data from marker-based/markerless technologies were collected,along with ground reaction force data,from 16 young adults running on an instrumented treadmill at 3 speeds:2.24 m/s,2.91 m/s,and 3.58 m/s(5.0 miles/h,6.5 miles/h,and 8.0 miles/h).Sagittal plane moments and powers of the hip,knee,and ankle were calculated by inverse dynamic methods.Time series analysis and statistical parametric mapping were used to determine system differences.Results:Compared to the marker-based system,the markerless system estimated increased lower extremity joint kinetics with faster speed during the swing phase in most cases.Conclusion:Despite the promising application of markerless technology in clinical settings,systematic markerless overestimation requires focused attention.Based on segment pose estimations,the centers of mass estimated by markerless technologies were farther away from the relevant distal joint centers,which led to greater joint moments and powers estimates by markerless vs.marker-based systems.The differences were amplified by running speed.展开更多
Aiming at the human–computer interaction control(HCIC)requirements of multi operators in collaborative virtual maintenance(CVM),real-time motion capture and simulation drive of multi operators with optical human moti...Aiming at the human–computer interaction control(HCIC)requirements of multi operators in collaborative virtual maintenance(CVM),real-time motion capture and simulation drive of multi operators with optical human motion capture system(HMCS)is proposed.The detailed realization process of real-time motion capture and data drive for virtual operators in CVM environment is presented to actualize the natural and online interactive operations.In order to ensure the cooperative and orderly interactions of virtual operators with the input operations of actual operators,collaborative HCIC model is established according to specific planning,allocating and decision-making of different maintenance tasks as well as the human–computer interaction features and collaborative maintenance operation features among multi maintenance trainees in CVM process.Finally,results of the experimental implementation validate the effectiveness and practicability of proposed methods,models,strategies and mechanisms.展开更多
A wearable micro-sensor motion capture system with 16 IMUs and an error-compensatory complementary filter algorithm for real-time motion estimation has been developed to acquire accurate 3D orientation and displacemen...A wearable micro-sensor motion capture system with 16 IMUs and an error-compensatory complementary filter algorithm for real-time motion estimation has been developed to acquire accurate 3D orientation and displacement in real life activities.In the proposed filter algorithm,the gyroscope bias error,orientation error and magnetic disturbance error are estimated and compensated,significantly reducing the orientation estimation error due to sensor noise and drift.Displacement estimation,especially for activities such as jumping,has been the challenge in micro-sensor motion capture.An adaptive gait phase detection algorithm has been developed to accommodate accurate displacement estimation in different types of activities.The performance of this system is benchmarked with respect to the results of VICON optical capture system.The experimental results have demonstrated effectiveness of the system in daily activities tracking,with estimation error 0.16 ± 0.06m for normal walking and 0.13 ± 0.11m for jumping motions.展开更多
In recent years,the use of inertial measurement unit(IMU)-based motion capture(Mocap)systems in rehabilitation has grown significantly.This paper aimed to provide an overview of current IMUbased Mocap system designs i...In recent years,the use of inertial measurement unit(IMU)-based motion capture(Mocap)systems in rehabilitation has grown significantly.This paper aimed to provide an overview of current IMUbased Mocap system designs in the field of rehabilitation,explore the specific applications and implementation of these systems,and discuss potential future developments considering sensor limitations.For this review,a systematic literature search was conducted using Scopus,IEEE Xplore,PubMed,and Web of Science from 2013 to 2022.A total of 65 studies were included and analyzed based on their rehabilitation application,target population,and system deployment and measurement.The proportion of rehabilitation assessment,training,and both were 82%,12%,and 6%respectively.The results showed that primary focus of the studies was stroke that was one of the most commonly studied pathological disease.Additionally,general rehabilitation without targeting a specific pathology was also examined widely,with a particular emphasis on gait analysis.The most common sensor configuration for gait analysis was two IMUs measuring spatiotemporal parameters of the lower limb.However,the lack of training applications and upper limb studies could be attributed to the limited battery life and sensor drift.To address this issue,the use of low-power chips and low-consumption transmission pathways was a potential way to extend usage time for long-term training.Furthermore,we suggest the development of a highly integrated multi-modal system with sensor fusion.展开更多
Integrated energy systems(IESs)can improve energy efficiency and reduce carbon emissions,essential for achieving peak carbon emissions and carbon neutrality.This study investigated the characteristics of the CHP model...Integrated energy systems(IESs)can improve energy efficiency and reduce carbon emissions,essential for achieving peak carbon emissions and carbon neutrality.This study investigated the characteristics of the CHP model considering P2G and carbon capture systems,and a two-stage robust optimization model of the electricity-heat-gascold integrated energy system was developed.First,a CHP model considering the P2G and carbon capture system was established,and the electric-thermal coupling characteristics and P2G capacity constraints of the model were derived,which proved that the model could weaken the electric-thermal coupling characteristics,increase the electric power regulation range,and reduce carbon emissions.Subsequently,a two-stage robust optimal scheduling model of an IES was constructed,in which the objective function in the day-ahead scheduling stage was to minimize the start-up and shutdown costs.The objective function in the real-time scheduling stage was to minimize the equipment operating costs,carbon emission costs,wind curtailment,and solar curtailment costs,considering multiple uncertainties.Finally,after the objective function is linearized with a ψ-piecewise method,the model is solved based on the C&CG algorithm.Simulation results show that the proposed model can effectively absorb renewable energy and reduce the total cost of the system.展开更多
The essential requirements of the end-effector of large space manipulator are capabilities of misalignment tolerance and soft capture.According to these requirements,an end-effector prototype combining the tendon-shea...The essential requirements of the end-effector of large space manipulator are capabilities of misalignment tolerance and soft capture.According to these requirements,an end-effector prototype combining the tendon-sheath transmission system with steel cable snaring mechanism was manufactured.An analysis method based on the coordinate transformation and the projection of key points of the mechanical interface was proposed,and it was a guideline of the end-effector design.Furthermore,the tendon-sheath transmission system was employed in the capture subassembly to reduce the inertia of the capture mechanism and enlarge the capture space.The capabilities of misalignment tolerance and soft capture were validated through the dynamic simulation in ADAMS software.The results of the capture simulation and experiment show that the end-effector has outstanding capabilities of misalignment tolerance and soft capture.The translation misalignments in radial directions are±100 mm,and angular misalignments about pitch and yaw are±15°.展开更多
Among the wave energy converters (WECs), oscillating buoy is a promising type for wave energy development in offshore area. Conventional single-freedom oscillating buoy WECs with linear power take-off (PTO) system are...Among the wave energy converters (WECs), oscillating buoy is a promising type for wave energy development in offshore area. Conventional single-freedom oscillating buoy WECs with linear power take-off (PTO) system are less efficient under off-resonance conditions and have a narrow power capture bandwidth. Thus, a multi-freedom WEC with a nonlinear PTO system is proposed. This study examines a multi-freedom WEC with 3 degrees of freedom: surge, heave and pitch. Three different PTO systems (velocity-square, snap through, and constant PTO systems) and a traditional linear PTO system are applied to the WEC. A time-domain model is established using linear potential theory and Cummins equation. The kinematic equation is numerically calculated with the fourth-order Runge–Kutta method. The optimal average output power of the PTO systems in all degrees of freedom are obtained and compared. Other parameters of snap through PTO are also discussed in detail. Results show that according to the power capture performance, the order of the PTO systems from the best to worst is snap through PTO, constant PTO, linear PTO and velocity-square PTO. The resonant frequency of the WEC can be adjusted to the incident wave frequency by choosing specific parameters of the snap through PTO. Adding more DOFs can make the WEC get a better power performance in more wave frequencies. Both the above two methods can raise the WEC’s power capture performance significantly.展开更多
The libration control problem of space tether system(STS)for post-capture of payload is studied.The process of payload capture will cause tether swing and deviation from the nominal position,resulting in the failure o...The libration control problem of space tether system(STS)for post-capture of payload is studied.The process of payload capture will cause tether swing and deviation from the nominal position,resulting in the failure of capture mission.Due to unknown inertial parameters after capturing the payload,an adaptive optimal control based on policy iteration is developed to stabilize the uncertain dynamic system in the post-capture phase.By introducing integral reinforcement learning(IRL)scheme,the algebraic Riccati equation(ARE)can be online solved without known dynamics.To avoid computational burden from iteration equations,the online implementation of policy iteration algorithm is provided by the least-squares solution method.Finally,the effectiveness of the algorithm is validated by numerical simulations.展开更多
The objective of this study was to determine the efficiency of different plant systems in capturing deep soil nitrate (NO3-) to reduce NO3- leaching in a field plot experiment using 15N labelling. The study was cond...The objective of this study was to determine the efficiency of different plant systems in capturing deep soil nitrate (NO3-) to reduce NO3- leaching in a field plot experiment using 15N labelling. The study was conducted on a calcareous alluvial soil on the North China Plains and the plant systems evaluated included alfalfa (Medicago sativa), American black poplar (Populus nigra) and cocksfoot (Dactylis). ^15N-labelled N fertilizer was injected to 90 cm depth to determine the recovery of ^15N by the plants. With conventional water and nutrient management, the total recovery of ^15N-labeled NO3--N was 23.4% by alfalfa after two consecutive growth years. The recovery was significantly higher than those by American black poplar (12.3%) and cocksfoot (11.4%). The highest proportion of soil residual ~SN from the labeled fertilizer N (%Ndff) was detected around 90 cm soil depth at the time of the 1st year harvest and at 110-130 cm soil depth at time of the 2nd year harvest. Soil %Ndff in 0-80 cm depth was significantly higher in the alfalfa treatment than those in all the other treatments. The soil %Ndff below 100 cm depth was much lower in the alfalfa than those in all the other treatments. These results indicated that ^15N leaching losses in the alfalfa treatment were significantly lower than by those in the black poplar and cocksfoot treatments, due to the higher root density located in nitrate labeling zone of soil profile. In conclusion, alfalfa may be used as a plant to capture deep soil NO3- left from previous crops to reduce NO3- leaching in high intensity crop cultivation systems of North China Plain.展开更多
This paper presents the application of a neural network rule extraction algorithm,called the piecewise linear artificial neural network or PWL-ANN algorithm,on a carbon capture process system dataset.The objective of ...This paper presents the application of a neural network rule extraction algorithm,called the piecewise linear artificial neural network or PWL-ANN algorithm,on a carbon capture process system dataset.The objective of the application is to enhance understanding of the intricate relationships among the key process parameters.The algorithm extracts rules in the form of multiple linear regression equations by approximating the sigmoid activation functions of the hidden neurons in an artificial neural network(ANN).The PWL-ANN algorithm overcomes the weaknesses of the statistical regression approach,in which accuracies of the generated predictive models are often not satisfactory,and the opaqueness of the ANN models.The results show that the generated PWL-ANN models have accuracies that are as high as the originally trained ANN models of the four datasets of the carbon capture process system.An analysis of the extracted rules and the magnitude of the coefficients in the equations revealed that the three most significant parameters of the CO_(2) production rate are the steam flow rate through reboiler,reboiler pressure,and the CO_(2) concentration in the flue gas.展开更多
Boron neutron capture therapy (BNCT) is based on the incorporation of boron-containing drugs to cancer cells and the nuclear reaction of 10B atoms by thermal neutron irradiation results in tumor degeneration. For the ...Boron neutron capture therapy (BNCT) is based on the incorporation of boron-containing drugs to cancer cells and the nuclear reaction of 10B atoms by thermal neutron irradiation results in tumor degeneration. For the development of this therapy, currently, long time and high cost consuming experiments using many animals are required. In this study, we constructed a new in vitro evaluation system for BNCT by combination of an artificial tumor tissue model, comprised of normal human dermal-derived fibroblast (NHDF) and human pancreatic cancer cell line BxPC3, and the optical plastic material CR-39 as a solid state nuclear track detector. Administration of boronophenylalanine (10BPA) as a boron-containing drug and neutron irradiation up to 2.52 × 1012 n/cm2 to the control tissue constructed by NHDF (NHDF3D) and BxPC3 cell loaded tissue (NHDF3D/BxPC3) resulted in detection of 1.6 times higher number of α-ray/recoiled Li particle tracks in NHDF3D/BxPC3 in comparison to NHDF3D, demonstrating that putative irradiation damage to cancer cells can be evaluated by this system. On a cellular level, the hit number of α-ray/recoiled Li particle tracks per single BxPC3 cells and NHDF was evaluated as 5.46 and 1.71, respectively. The tumor and normal tissue ratio (T/N ratio) was 3.19, which was corresponded with those of BPA as 2 - 4 that reported in the previous studies. This new in vitro evaluation system may provide a useful tool for a low cost, labor-saving, and non-animal method for the development of new boron-containing drugs or improvement of BNCT conditions.展开更多
Ammonia(NH3)is a carbon-free,hydrogen-rich chemical related to global food safety,clean energy,and environmental protection.As an essential technology for meeting the requirements raised by such issues,NH3 capture has...Ammonia(NH3)is a carbon-free,hydrogen-rich chemical related to global food safety,clean energy,and environmental protection.As an essential technology for meeting the requirements raised by such issues,NH3 capture has been intensively explored by researchers in both fundamental and applied fields.The four typical methods used are(1)solvent absorption by ionic liquids and their derivatives,(2)adsorption by porous solids,(3)abadsorption by porous liquids,and(4)membrane separation.Rooted in the development of advanced materials for NH3 capture,we conducted a coherent review of the design of different materials,mainly in the past 5 years,their interactions with NH3 molecules and construction of transport pathways,as well as the structure–property relationship,with specific examples discussed.Finally,the challenges in current research and future worthwhile directions for NH3 capture materials are proposed.展开更多
The Joule-Thomson effect is one of the important thermodynamic properties in the system relevant to gas switching reforming with carbon capture and storage(CCS). In this work, a set of apparatus was set up to determin...The Joule-Thomson effect is one of the important thermodynamic properties in the system relevant to gas switching reforming with carbon capture and storage(CCS). In this work, a set of apparatus was set up to determine the Joule-Thomson effect of binary mixtures(CO_(2)+ H_(2)). The accuracy of the apparatus was verified by comparing with the experimental data of carbon dioxide. The Joule-Thomson coefficients(μ_(JT)) for(CO_(2)+ H_(2)) binary mixtures with mole fractions of carbon dioxide(x_(CO_(2))= 0.1, 0.26, 0.5,0.86, 0.94) along six isotherms at various pressures were measured. Five equations of state EOSs(PR,SRK, PR, BWR and GERG-2008 equation) were used to calculate the μ_(JT)for both pure systems and binary systems, among which the GERG-2008 predicted best with a wide range of pressure and temperature.Moreover, the Joule-Thomson inversion curves(JTIC) were calculated with five equations of state. A comparison was made between experimental data and predicted data for the inversion curve of CO_(2). The investigated EOSs show a similar prediction of the low-temperature branch of the JTIC for both pure and binary systems, except for the BWRS equation of state. Among all the equations, SRK has the most similar result to GERG-2008 for predicting JTIC.展开更多
Objective:To isolate ceils of cardiac conduction system (CCS) with laser capture microdissec tion (LCM) and extract and evaluate quality of small amount of RNA from ceils of CCS. Methods: Cryo star sections were...Objective:To isolate ceils of cardiac conduction system (CCS) with laser capture microdissec tion (LCM) and extract and evaluate quality of small amount of RNA from ceils of CCS. Methods: Cryo star sections were followed by H-E staining. 20 pieces of H-E stained eryostat sections were scraped and its RNA was assessed to insure that RNA didn't degrade in dyeing and dehydration process. Ceils of CCS were captured with LCM and quality of small amount of RNA was verified with RT-PCR. Results: Ceils of CCS isolated with LCM had clear morphology after staining. High quality RNA was extracted from LCM samples and scraped tissues; 18S rRNA and 28S rRNA were seen distinctly on gel eleetrophoresis. Low level of small amount of RNA extracted from LCM sample was below the limit of detection on gel eleetrophoresis or ultraviolet speetrophotometer. The housekeeping genes β-aetin and GAPDH were successfully amplified with small amount of RNA. Conclusion :This study resolves the problem of acquiring material of CCS precisely that hinders gene research of CCS. It is found out that the method is easy and reliable to extract and assess the quality of small amount of RNA from mierodisseeted ceils of CCS.展开更多
As the effective capture region of optical motion capture system is limited by quantity,installation mode,resolution and focus of infrared cameras,the reflective markers on certain body parts(such as wrists,elbows,etc...As the effective capture region of optical motion capture system is limited by quantity,installation mode,resolution and focus of infrared cameras,the reflective markers on certain body parts(such as wrists,elbows,etc.)of multi-actual trainees may be obscured when they perform the collaborative interactive operation.To address this issue,motion data compensation method based on the additional feature information provided by the electromagnetic spatial position tracking equipment is proposed in this paper.The main working principle and detailed realization process of the proposed method are introduced step by step,and the practical implementation is presented to illustrate its validity and efficiency.The results show that the missing capture data and motion information of relevant obscured markers on arms can be retrieved with the proposed method,which can avoid the simulation motions of corresponding virtual operators being interrupted and deformed during the collaborative interactive operation process performed by multiactual trainees with optical human motion capture system in a limited capture range.展开更多
The paper aims to execute puppet without restrictions by controling puppet using robot. We controling puppet in the same way as the present puppet, but we perform this by robot. It offers more advantages and lessen th...The paper aims to execute puppet without restrictions by controling puppet using robot. We controling puppet in the same way as the present puppet, but we perform this by robot. It offers more advantages and lessen the weak points. It needs various actions and expressions because of the nature of a puppet. The biggest problem which executes this is the ways to create a system. This thesis proposes motion capture of developed method with solution of this problem. So, we create various contents needed by puppet. In this part, developed method means a mixed method on the basis of optical system and magnetic system used mainly for the present method of motion capture. We lessen the weak points of each method and propoe solution of create motion for pupct by offering more advantages. So we solve difficulties of executing puppet and probable probkans when we execute puppet by using robot. The solution of this thesis is proven by applying control of puppet.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos.52175279 and 51705459)the Natural Science Foundation of Zhejiang Province,China (Grant No.LY20E050022)the Key Research and Development Projects of Zhejiang Provincial Science and Technology Department (Grant No.2021C03122)。
文摘This paper presented a novel tinny motion capture system for measuring bird posture based on inertial and magnetic measurement units that are made up of micromachined gyroscopes, accelerometers, and magnetometers. Multiple quaternion-based extended Kalman filters were implemented to estimate the absolute orientations to achieve high accuracy.Under the guidance of ornithology experts, the extending/contracting motions and flapping cycles were recorded using the developed motion capture system, and the orientation of each bone was also analyzed. The captured flapping gesture of the Falco peregrinus is crucial to the motion database of raptors as well as the bionic design.
基金supported by the National Natural Science Foundation of China (61503392)。
文摘This study presents a kinematic calibration method for exoskeletal inertial motion capture (EI-MoCap) system with considering the random colored noise such as gyroscopic drift.In this method, the geometric parameters are calibrated by the traditional calibration method at first. Then, in order to calibrate the parameters affected by the random colored noise, the expectation maximization (EM) algorithm is introduced. Through the use of geometric parameters calibrated by the traditional calibration method, the iterations under the EM framework are decreased and the efficiency of the proposed method on embedded system is improved. The performance of the proposed kinematic calibration method is compared to the traditional calibration method. Furthermore, the feasibility of the proposed method is verified on the EI-MoCap system. The simulation and experiment demonstrate that the motion capture precision is significantly improved by 16.79%and 7.16%respectively in comparison to the traditional calibration method.
基金National Science Foundation (CBET 1927336)Saudi Aramco,and the Lenfest Center for Sustainable Energy at the Earth Institute at Columbia University for financially supporting this work+3 种基金performed at GeoSoilEnviroCARS (The University of Chicago,Sector 13)Advanced Photon Source (APS),Argonne National Laboratory.GeoSoilEnviroCARS is supported by the National Science Foundation-Earth Sciences (EAR-1634415)the Department of Energy-GeoSciences (DE-FG02-94ER14466)the Advanced Photon Source,a U.S.Department of Energy (DOE)Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No.DE-AC02-06CH11357.
文摘Metal-Organic Frameworks(MOFs)have been developed as solid sorbents for CO_(2) capture applications and their properties can be controlled by tuning the chemical blocks of their crystalline units.A number of MOFs(e.g.,HKUST-1)have been developed but the question remains how to deploy them for gas-solid contact.Unfortunately,the direct use of MOFs as nanocrystals would lead to serious problems and risks.Here,for the first time,we report a novel MOF-based hybrid sorbent that is produced via an innovative in-situ microencapsulated synthesis.Using a custom-made double capillary microfluidic assembly,double emulsions of the MOF precursor solutions and UV-curable silicone shell fluid are produced.Subsequently,HKUST-1 MOF is successfully synthesized within the droplets enclosed in the gas permeable microcapsules.The developed MOF-bearing microcapsules uniquely allow the deployment of functional nanocrystals without the challenge of handling ultrafine particles,and further,can selectively reject undesired compounds to protect encapsulated MOFs.
基金supported by the National Science Fund for Distinguished Young Scholars(22125804)the National Natural Science Foundation of China(21808110,22078155,and 21878149).
文摘Temperature-swing adsorption(TSA)is an effective technique for CO_(2) capture,but the temperature swing procedure is energy-intensive.Herein,we report a low-energy-consumption system by combining passive radiative cooling and solar heating for the uptake of CO_(2) on commercial activated carbons(CACs).During adsorption,the adsorbents are coated with a layer of hierarchically porous poly(vinylidene fluoride-co-hexafluoropropene)[P(VdF-HFP)HP],which cools the adsorbents to a low temperature under sunlight through radiative cooling.For desorption,CACs with broad absorption of the solar spectrum are exposed to light irradiation for heating.The heating and cooling processes are completely driven by solar energy.Adsorption tests under mimicked sunlight using the CACs show that the performance of this system is comparable to that of the traditional ones.Furthermore,under real sunlight irradiation,the adsorption capacity of the CACs can be well maintained after multiple cycles.The present work may inspire the development of new temperature swing procedures with little energy consumption.
文摘Background:The development of computer vision technology has enabled the use of markerless movement tracking for biomechanical analysis.Recent research has reported the feasibility of markerless systems in motion analysis but has yet to fully explore their utility for capturing faster movements,such as running.Applied studies using markerless systems in clinical and sports settings are still lacking.Thus,the present study compared running biomechanics estimated by marker-based and markerless systems.Given running speed not only affects sports performance but is also associated with clinical injury prevention,diagnosis,and rehabilitation,we aimed to investigate the effects of speed on the comparison of estimated lower extremity joint moments and powers between markerless and marker-based technologies during treadmill running as a concurrent validating study.Methods:Kinematic data from marker-based/markerless technologies were collected,along with ground reaction force data,from 16 young adults running on an instrumented treadmill at 3 speeds:2.24 m/s,2.91 m/s,and 3.58 m/s(5.0 miles/h,6.5 miles/h,and 8.0 miles/h).Sagittal plane moments and powers of the hip,knee,and ankle were calculated by inverse dynamic methods.Time series analysis and statistical parametric mapping were used to determine system differences.Results:Compared to the marker-based system,the markerless system estimated increased lower extremity joint kinetics with faster speed during the swing phase in most cases.Conclusion:Despite the promising application of markerless technology in clinical settings,systematic markerless overestimation requires focused attention.Based on segment pose estimations,the centers of mass estimated by markerless technologies were farther away from the relevant distal joint centers,which led to greater joint moments and powers estimates by markerless vs.marker-based systems.The differences were amplified by running speed.
文摘Aiming at the human–computer interaction control(HCIC)requirements of multi operators in collaborative virtual maintenance(CVM),real-time motion capture and simulation drive of multi operators with optical human motion capture system(HMCS)is proposed.The detailed realization process of real-time motion capture and data drive for virtual operators in CVM environment is presented to actualize the natural and online interactive operations.In order to ensure the cooperative and orderly interactions of virtual operators with the input operations of actual operators,collaborative HCIC model is established according to specific planning,allocating and decision-making of different maintenance tasks as well as the human–computer interaction features and collaborative maintenance operation features among multi maintenance trainees in CVM process.Finally,results of the experimental implementation validate the effectiveness and practicability of proposed methods,models,strategies and mechanisms.
基金supported by the National Natural Science Foundation of China(Nos.61431017,81272166)
文摘A wearable micro-sensor motion capture system with 16 IMUs and an error-compensatory complementary filter algorithm for real-time motion estimation has been developed to acquire accurate 3D orientation and displacement in real life activities.In the proposed filter algorithm,the gyroscope bias error,orientation error and magnetic disturbance error are estimated and compensated,significantly reducing the orientation estimation error due to sensor noise and drift.Displacement estimation,especially for activities such as jumping,has been the challenge in micro-sensor motion capture.An adaptive gait phase detection algorithm has been developed to accommodate accurate displacement estimation in different types of activities.The performance of this system is benchmarked with respect to the results of VICON optical capture system.The experimental results have demonstrated effectiveness of the system in daily activities tracking,with estimation error 0.16 ± 0.06m for normal walking and 0.13 ± 0.11m for jumping motions.
基金supports from Shenzhen Science and Technology Program(JCYJ20220530113811027,JCYJ20220818103602004,and JCYJ20210324104203010)Shenzhen Key Laboratory of Smart Healthcare Engineering(ZDSYS20200811144003009)+2 种基金the National Key Research and Development Program of China(2022YFF1202500,2022YFF1202502)the Funds for the Cultivation of Guangdong College Students’Scientific and Technological Innovation,China("Climbing Program"Special Funds,pdjh2023c11305)College Students’Innovative Entrepreneurial Training Plan Program,China(Y01381868).
文摘In recent years,the use of inertial measurement unit(IMU)-based motion capture(Mocap)systems in rehabilitation has grown significantly.This paper aimed to provide an overview of current IMUbased Mocap system designs in the field of rehabilitation,explore the specific applications and implementation of these systems,and discuss potential future developments considering sensor limitations.For this review,a systematic literature search was conducted using Scopus,IEEE Xplore,PubMed,and Web of Science from 2013 to 2022.A total of 65 studies were included and analyzed based on their rehabilitation application,target population,and system deployment and measurement.The proportion of rehabilitation assessment,training,and both were 82%,12%,and 6%respectively.The results showed that primary focus of the studies was stroke that was one of the most commonly studied pathological disease.Additionally,general rehabilitation without targeting a specific pathology was also examined widely,with a particular emphasis on gait analysis.The most common sensor configuration for gait analysis was two IMUs measuring spatiotemporal parameters of the lower limb.However,the lack of training applications and upper limb studies could be attributed to the limited battery life and sensor drift.To address this issue,the use of low-power chips and low-consumption transmission pathways was a potential way to extend usage time for long-term training.Furthermore,we suggest the development of a highly integrated multi-modal system with sensor fusion.
基金supported by the National Natural Science Foundation of China(Grant number 51977154)。
文摘Integrated energy systems(IESs)can improve energy efficiency and reduce carbon emissions,essential for achieving peak carbon emissions and carbon neutrality.This study investigated the characteristics of the CHP model considering P2G and carbon capture systems,and a two-stage robust optimization model of the electricity-heat-gascold integrated energy system was developed.First,a CHP model considering the P2G and carbon capture system was established,and the electric-thermal coupling characteristics and P2G capacity constraints of the model were derived,which proved that the model could weaken the electric-thermal coupling characteristics,increase the electric power regulation range,and reduce carbon emissions.Subsequently,a two-stage robust optimal scheduling model of an IES was constructed,in which the objective function in the day-ahead scheduling stage was to minimize the start-up and shutdown costs.The objective function in the real-time scheduling stage was to minimize the equipment operating costs,carbon emission costs,wind curtailment,and solar curtailment costs,considering multiple uncertainties.Finally,after the objective function is linearized with a ψ-piecewise method,the model is solved based on the C&CG algorithm.Simulation results show that the proposed model can effectively absorb renewable energy and reduce the total cost of the system.
基金Project(2006AA04Z228) supported by National Hi-tech Research and Development Program of China
文摘The essential requirements of the end-effector of large space manipulator are capabilities of misalignment tolerance and soft capture.According to these requirements,an end-effector prototype combining the tendon-sheath transmission system with steel cable snaring mechanism was manufactured.An analysis method based on the coordinate transformation and the projection of key points of the mechanical interface was proposed,and it was a guideline of the end-effector design.Furthermore,the tendon-sheath transmission system was employed in the capture subassembly to reduce the inertia of the capture mechanism and enlarge the capture space.The capabilities of misalignment tolerance and soft capture were validated through the dynamic simulation in ADAMS software.The results of the capture simulation and experiment show that the end-effector has outstanding capabilities of misalignment tolerance and soft capture.The translation misalignments in radial directions are±100 mm,and angular misalignments about pitch and yaw are±15°.
基金financially supported by the Shandong Provincial Natural Science Key Basic Program(Grant No.ZR2017ZA0202)the Qingdao Municipal Science&Technology Program(Grant No.15-8-3-7-jch)Special Project for Marine Renewable Energy(Grant No.GHME2016YY02)
文摘Among the wave energy converters (WECs), oscillating buoy is a promising type for wave energy development in offshore area. Conventional single-freedom oscillating buoy WECs with linear power take-off (PTO) system are less efficient under off-resonance conditions and have a narrow power capture bandwidth. Thus, a multi-freedom WEC with a nonlinear PTO system is proposed. This study examines a multi-freedom WEC with 3 degrees of freedom: surge, heave and pitch. Three different PTO systems (velocity-square, snap through, and constant PTO systems) and a traditional linear PTO system are applied to the WEC. A time-domain model is established using linear potential theory and Cummins equation. The kinematic equation is numerically calculated with the fourth-order Runge–Kutta method. The optimal average output power of the PTO systems in all degrees of freedom are obtained and compared. Other parameters of snap through PTO are also discussed in detail. Results show that according to the power capture performance, the order of the PTO systems from the best to worst is snap through PTO, constant PTO, linear PTO and velocity-square PTO. The resonant frequency of the WEC can be adjusted to the incident wave frequency by choosing specific parameters of the snap through PTO. Adding more DOFs can make the WEC get a better power performance in more wave frequencies. Both the above two methods can raise the WEC’s power capture performance significantly.
基金supported by the National Natural Science Foundation of China(No.62111530051)the Fundamental Research Funds for the Central Universities(No.3102017JC06002)the Shaanxi Science and Technology Program,China(No.2017KW-ZD-04).
文摘The libration control problem of space tether system(STS)for post-capture of payload is studied.The process of payload capture will cause tether swing and deviation from the nominal position,resulting in the failure of capture mission.Due to unknown inertial parameters after capturing the payload,an adaptive optimal control based on policy iteration is developed to stabilize the uncertain dynamic system in the post-capture phase.By introducing integral reinforcement learning(IRL)scheme,the algebraic Riccati equation(ARE)can be online solved without known dynamics.To avoid computational burden from iteration equations,the online implementation of policy iteration algorithm is provided by the least-squares solution method.Finally,the effectiveness of the algorithm is validated by numerical simulations.
基金financially supported by the Provincial Natural Science Foundation of Hebei Province in China(C2006000491)the financial support from the National Natural Science Foundation of China(30571110,31172033)the National 863 Program of China(2012AA101403-3)
文摘The objective of this study was to determine the efficiency of different plant systems in capturing deep soil nitrate (NO3-) to reduce NO3- leaching in a field plot experiment using 15N labelling. The study was conducted on a calcareous alluvial soil on the North China Plains and the plant systems evaluated included alfalfa (Medicago sativa), American black poplar (Populus nigra) and cocksfoot (Dactylis). ^15N-labelled N fertilizer was injected to 90 cm depth to determine the recovery of ^15N by the plants. With conventional water and nutrient management, the total recovery of ^15N-labeled NO3--N was 23.4% by alfalfa after two consecutive growth years. The recovery was significantly higher than those by American black poplar (12.3%) and cocksfoot (11.4%). The highest proportion of soil residual ~SN from the labeled fertilizer N (%Ndff) was detected around 90 cm soil depth at the time of the 1st year harvest and at 110-130 cm soil depth at time of the 2nd year harvest. Soil %Ndff in 0-80 cm depth was significantly higher in the alfalfa treatment than those in all the other treatments. The soil %Ndff below 100 cm depth was much lower in the alfalfa than those in all the other treatments. These results indicated that ^15N leaching losses in the alfalfa treatment were significantly lower than by those in the black poplar and cocksfoot treatments, due to the higher root density located in nitrate labeling zone of soil profile. In conclusion, alfalfa may be used as a plant to capture deep soil NO3- left from previous crops to reduce NO3- leaching in high intensity crop cultivation systems of North China Plain.
基金The first author is grateful for the scholarships and generous support from the Faculty of Graduate Studies and Research,University of Regina and from the Canada Research Chair Program.
文摘This paper presents the application of a neural network rule extraction algorithm,called the piecewise linear artificial neural network or PWL-ANN algorithm,on a carbon capture process system dataset.The objective of the application is to enhance understanding of the intricate relationships among the key process parameters.The algorithm extracts rules in the form of multiple linear regression equations by approximating the sigmoid activation functions of the hidden neurons in an artificial neural network(ANN).The PWL-ANN algorithm overcomes the weaknesses of the statistical regression approach,in which accuracies of the generated predictive models are often not satisfactory,and the opaqueness of the ANN models.The results show that the generated PWL-ANN models have accuracies that are as high as the originally trained ANN models of the four datasets of the carbon capture process system.An analysis of the extracted rules and the magnitude of the coefficients in the equations revealed that the three most significant parameters of the CO_(2) production rate are the steam flow rate through reboiler,reboiler pressure,and the CO_(2) concentration in the flue gas.
文摘Boron neutron capture therapy (BNCT) is based on the incorporation of boron-containing drugs to cancer cells and the nuclear reaction of 10B atoms by thermal neutron irradiation results in tumor degeneration. For the development of this therapy, currently, long time and high cost consuming experiments using many animals are required. In this study, we constructed a new in vitro evaluation system for BNCT by combination of an artificial tumor tissue model, comprised of normal human dermal-derived fibroblast (NHDF) and human pancreatic cancer cell line BxPC3, and the optical plastic material CR-39 as a solid state nuclear track detector. Administration of boronophenylalanine (10BPA) as a boron-containing drug and neutron irradiation up to 2.52 × 1012 n/cm2 to the control tissue constructed by NHDF (NHDF3D) and BxPC3 cell loaded tissue (NHDF3D/BxPC3) resulted in detection of 1.6 times higher number of α-ray/recoiled Li particle tracks in NHDF3D/BxPC3 in comparison to NHDF3D, demonstrating that putative irradiation damage to cancer cells can be evaluated by this system. On a cellular level, the hit number of α-ray/recoiled Li particle tracks per single BxPC3 cells and NHDF was evaluated as 5.46 and 1.71, respectively. The tumor and normal tissue ratio (T/N ratio) was 3.19, which was corresponded with those of BPA as 2 - 4 that reported in the previous studies. This new in vitro evaluation system may provide a useful tool for a low cost, labor-saving, and non-animal method for the development of new boron-containing drugs or improvement of BNCT conditions.
基金financially supported by the National Natural Science Foundation of China(22178357)CAS Project for Young Scientists in Basic Research(YSBR-038)+1 种基金the Youth Innovation Promotion Association of the Chinese Academy of Sciences(2020047)the research fund of State Key Laboratory of Mesoscience and Engineering(MESO-23-A07,MESO-23-T02)。
文摘Ammonia(NH3)is a carbon-free,hydrogen-rich chemical related to global food safety,clean energy,and environmental protection.As an essential technology for meeting the requirements raised by such issues,NH3 capture has been intensively explored by researchers in both fundamental and applied fields.The four typical methods used are(1)solvent absorption by ionic liquids and their derivatives,(2)adsorption by porous solids,(3)abadsorption by porous liquids,and(4)membrane separation.Rooted in the development of advanced materials for NH3 capture,we conducted a coherent review of the design of different materials,mainly in the past 5 years,their interactions with NH3 molecules and construction of transport pathways,as well as the structure–property relationship,with specific examples discussed.Finally,the challenges in current research and future worthwhile directions for NH3 capture materials are proposed.
基金supported by the National Natural Science Foundation of China (21878056)Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology (2019Z002)。
文摘The Joule-Thomson effect is one of the important thermodynamic properties in the system relevant to gas switching reforming with carbon capture and storage(CCS). In this work, a set of apparatus was set up to determine the Joule-Thomson effect of binary mixtures(CO_(2)+ H_(2)). The accuracy of the apparatus was verified by comparing with the experimental data of carbon dioxide. The Joule-Thomson coefficients(μ_(JT)) for(CO_(2)+ H_(2)) binary mixtures with mole fractions of carbon dioxide(x_(CO_(2))= 0.1, 0.26, 0.5,0.86, 0.94) along six isotherms at various pressures were measured. Five equations of state EOSs(PR,SRK, PR, BWR and GERG-2008 equation) were used to calculate the μ_(JT)for both pure systems and binary systems, among which the GERG-2008 predicted best with a wide range of pressure and temperature.Moreover, the Joule-Thomson inversion curves(JTIC) were calculated with five equations of state. A comparison was made between experimental data and predicted data for the inversion curve of CO_(2). The investigated EOSs show a similar prediction of the low-temperature branch of the JTIC for both pure and binary systems, except for the BWRS equation of state. Among all the equations, SRK has the most similar result to GERG-2008 for predicting JTIC.
文摘Objective:To isolate ceils of cardiac conduction system (CCS) with laser capture microdissec tion (LCM) and extract and evaluate quality of small amount of RNA from ceils of CCS. Methods: Cryo star sections were followed by H-E staining. 20 pieces of H-E stained eryostat sections were scraped and its RNA was assessed to insure that RNA didn't degrade in dyeing and dehydration process. Ceils of CCS were captured with LCM and quality of small amount of RNA was verified with RT-PCR. Results: Ceils of CCS isolated with LCM had clear morphology after staining. High quality RNA was extracted from LCM samples and scraped tissues; 18S rRNA and 28S rRNA were seen distinctly on gel eleetrophoresis. Low level of small amount of RNA extracted from LCM sample was below the limit of detection on gel eleetrophoresis or ultraviolet speetrophotometer. The housekeeping genes β-aetin and GAPDH were successfully amplified with small amount of RNA. Conclusion :This study resolves the problem of acquiring material of CCS precisely that hinders gene research of CCS. It is found out that the method is easy and reliable to extract and assess the quality of small amount of RNA from mierodisseeted ceils of CCS.
基金the project supported by the National Natural Science Foundation of China(Grant No.61702524)the Natural Science Foundation of Shaanxi Province(Grant No.2016JQ6052).
文摘As the effective capture region of optical motion capture system is limited by quantity,installation mode,resolution and focus of infrared cameras,the reflective markers on certain body parts(such as wrists,elbows,etc.)of multi-actual trainees may be obscured when they perform the collaborative interactive operation.To address this issue,motion data compensation method based on the additional feature information provided by the electromagnetic spatial position tracking equipment is proposed in this paper.The main working principle and detailed realization process of the proposed method are introduced step by step,and the practical implementation is presented to illustrate its validity and efficiency.The results show that the missing capture data and motion information of relevant obscured markers on arms can be retrieved with the proposed method,which can avoid the simulation motions of corresponding virtual operators being interrupted and deformed during the collaborative interactive operation process performed by multiactual trainees with optical human motion capture system in a limited capture range.
基金supported bythe Ministry of Knowledge Economy,Korea,the ITRC(Information Technology Research Center)support program(No.NIPA-2009-(C1090-0902-0007))
文摘The paper aims to execute puppet without restrictions by controling puppet using robot. We controling puppet in the same way as the present puppet, but we perform this by robot. It offers more advantages and lessen the weak points. It needs various actions and expressions because of the nature of a puppet. The biggest problem which executes this is the ways to create a system. This thesis proposes motion capture of developed method with solution of this problem. So, we create various contents needed by puppet. In this part, developed method means a mixed method on the basis of optical system and magnetic system used mainly for the present method of motion capture. We lessen the weak points of each method and propoe solution of create motion for pupct by offering more advantages. So we solve difficulties of executing puppet and probable probkans when we execute puppet by using robot. The solution of this thesis is proven by applying control of puppet.