Nail changes following upper extremity transplantation(UET)cannot be overlooked as they possess diagnostic and prognostic relevance in allotransplantation of upper limbs.This comprehensive review explores nail and nai...Nail changes following upper extremity transplantation(UET)cannot be overlooked as they possess diagnostic and prognostic relevance in allotransplantation of upper limbs.This comprehensive review explores nail and nail bed related changes encountered in UET recipients in the literature.The differential diagnosis of nail abnormalities in UET includes a wide range of systemic,local and iatrogenic conditions other than immune responses to the allograft.It requires interdisciplinary evaluation by primary transplant surgeons,pathologists,dermatologists and immunologists.The possible underlying mechanisms of nail pathology in UET and the management are discussed.It also underscores the importance of onychodystrophy and need for timely intervention and to improve outcomes in UET recipients.展开更多
Background:Muscular strength is a powerful marker of current health status and robust predictor of age-related disease and disability.Handgrip strength(HGS)using isometric dynamometry is a convenient,feasible,and wide...Background:Muscular strength is a powerful marker of current health status and robust predictor of age-related disease and disability.Handgrip strength(HGS)using isometric dynamometry is a convenient,feasible,and widely used method of assessing muscular strength among people of all ages.While adult HGS norms have been published for many countries,no study has yet synthesized available data to produce international norms.The objective of this study was to generate international sex-and age-specific norms for absolute and body size-normalized HGS across the adult lifespan.Methods:Systematic searches were conducted in 6 databases/web search engines(MEDLINE,SPORTDiscus,Embase,Web of Science,CINAHL,and Google Scholar)up to December 1,2023.We included full-text peer-reviewed observational studies that reported normative HGS data for adults aged ≥20 years by sex and age.Pseudo data were generated using Monte Carlo simulation following harmonization for methodo-logical variation.Population-weighted Generalized Additive Models for Location,Scale,and Shape were used to develop sex-and age-specific norms for absolute HGS(kg)and HGS normalized by height(Ht,m)squared(i.e.,HGS/Ht^(2)in kg/m^(2)).Norms were tabulated as percentile values(5th to 95th)and visualized as smoothed percentile curves.Results:We included data from 100 unique observational studies representing 2,405,863 adults(51.9%female)aged 20 to 100+years from 69 countries and regions tested from the year 2000 onward.On average,absolute and normalized HGS values negligibly improved throughout early adulthood,peaked from age 3039 years(at 49.7 kg(males)and 29.7 kg(females)for absolute HGS or 16.3 kg/m^(2)(males)and 11.3 kg/m^(2)(females)for HGS/Ht^(2)),and declined afterwards.The age-related decline in HGS accelerated from middle to late adulthood and was slightly larger for males than for females during middle adulthood.Conclusion:This study provides the world’s largest and most geographically comprehensive international norms for adult HGS by sex and age.These norms have utility for global peer-comparisons,health screening,and surveillance.展开更多
[Objective] The purpose of this study was to clarify the structure,growth pattern and histochemical localization of alkaloids in root system of Aconitum flavum Hand.-Mazz.[Method] Paraffin sectioning and histochemistr...[Objective] The purpose of this study was to clarify the structure,growth pattern and histochemical localization of alkaloids in root system of Aconitum flavum Hand.-Mazz.[Method] Paraffin sectioning and histochemistry were employed for performing the analysis in this study.[Result] The root system of Aconitum flavum Hand.-Mazz.consists of taproot,lateral root and adventitious root.The primary structure of root system is normal,but secondary structure shows abnormal.The cambium and the extra cambium of taproot form a ＂U＂-shaped secondary vascular bundle and tertiary bundle in abnormal secondary structure.The sieve tube group is made of little sieve tube group which is differentiated from primary phloem and cambium.Meanwhile,the secondary xylem in tuberous root also appears to be a ＂U＂ shape.Parenchyma cells of secondary phloem occupy most of the tuberous root.The sieve tube group of tuberous root is mainly differentiated from parenchyma cell of secondary phloem.[Conclusion] The difference in abnormal secondary structure of taproot and tuberous root are attributed to their varied cambium compose and activity pattern.Alkaloids are mainly accumulated in parenchyma cell of the inside cortex and between bundle in taproot,while parenchyma of secondary phloem and pith in tuberous root.展开更多
In order to overcome the drawbacks of traditional rehabilitation method,the robot-aided rehabilitation has been widely investigated for the recent years.And the hand rehabilitation robot,as one of the hot research fie...In order to overcome the drawbacks of traditional rehabilitation method,the robot-aided rehabilitation has been widely investigated for the recent years.And the hand rehabilitation robot,as one of the hot research fields,remains many challenging issues to be investigated.This paper presents a new hand exoskeleton system with some novel characteristics.Firstly,both active and passive rehabilitative motions are realized.Secondly,the device is elaborately designed and brings advantages in many aspects.For example,joint motion is accomplished by a parallelogram mechanism and high level motion control is therefore made very simple without the need of complicated kinematics.The adjustable joint limit design ensures that the actual joint angles don＇t exceed the joint range of motion（ROM） and thus the patient safety is guaranteed.This design can fit to the different patients with different joint ROM as well as to the dynamically changing ROM for individual patient.The device can also accommodate to some extent variety of hand sizes.Thirdly,the proposed control strategy simultaneously realizes the position control and force control with the motor driver which only works in force control mode.Meanwhile,the system resistance compensation is preliminary realized and the resisting force is effectively reduced.Some experiments were conducted to verify the proposed system.Experimentally collected data show that the achieved ROM is close to that of a healthy hand and the range of phalange length（ROPL） covers the size of a typical hand,satisfying the size need of regular hand rehabilitation.In order to evaluate the performance when it works as a haptic device in active mode,the equivalent moment of inertia（MOI） of the device was calculated.The results prove that the device has low inertia which is critical in order to obtain good backdrivability.The experiments also show that in the active mode the virtual interactive force is successfully feedback to the finger and the resistance is reduced by one-third;for the passive control mode,the desired trajectory is realized satisfactorily.展开更多
Teleoperation can assist people to complete various complex tasks in inaccessible or high-risk environments,in which a wearable hand exoskeleton is one of the key devices.Adequate adaptability would be available to en...Teleoperation can assist people to complete various complex tasks in inaccessible or high-risk environments,in which a wearable hand exoskeleton is one of the key devices.Adequate adaptability would be available to enable the master hand exoskeleton to capture the motion of human fingers and reproduce the contact force between the slave hand and its object.This paper presents a novel finger exoskeleton based on the cascading four-link closed-loop kinematic chain.Each finger has an independent closed-loop kinematic chain,and the angle sensors are used to obtain the finger motion including the flexion/extension and the adduction/abduction.The cable tension is changed by the servo motor to transmit the contact force to the fingers in real time.Based on the finger exoskeleton,an adaptive hand exoskeleton is consequently developed.In addition,the hand exoskeleton is tested in a master-slave system.The experiment results show that the adaptive hand exoskeleton can be worn without any mechanical constraints,and the slave hand can follow the motions of each human finger.The accuracy and the real-time capability of the force reproduction are validated.The proposed adaptive hand exoskeleton can be employed as the master hand to remotely control the humanoid five-fingered dexterous slave hand,thus,enabling the teleoperation system to complete complex dexterous manipulation tasks.展开更多
Hand veins can be used effectively in biometric recognition since they are internal organs that,in contrast to fingerprints,are robust under external environment effects such as dirt and paper cuts.Moreover,they form ...Hand veins can be used effectively in biometric recognition since they are internal organs that,in contrast to fingerprints,are robust under external environment effects such as dirt and paper cuts.Moreover,they form a complex rich shape that is unique,even in identical twins,and allows a high degree of freedom.However,most currently employed hand-based biometric systems rely on hand-touch devices to capture images with the desired quality.Since the start of the COVID-19 pandemic,most handbased biometric systems have become undesirable due to their possible impact on the spread of the pandemic.Consequently,new contactless hand-based biometric recognition systems and databases are desired to keep up with the rising hygiene awareness.One contribution of this research is the creation of a database for hand dorsal veins images obtained contact-free with a variation in capturing distance and rotation angle.This database consists of 1548 images collected from 86 participants whose ages ranged from 19 to 84 years.For the other research contribution,a novel geometrical feature extraction method has been developed based on the Curvelet Transform.This method is useful for extracting robust rotation invariance features from vein images.The database attributes and the veins recognition results are analyzed to demonstrate their efficacy.展开更多
Previous studies have demonstrated that hand shadows may activate the motor cortex associated with the mirror neuron system in human brain. However, there is no evidence of activity of the human mirror neuron system d...Previous studies have demonstrated that hand shadows may activate the motor cortex associated with the mirror neuron system in human brain. However, there is no evidence of activity of the human mirror neuron system during the observation of intransitive movements by shadows and line drawings of hands. This study examined the suppression of electroencephalography mu waves （8-13 Hz） induced by observation of stimuli in 18 healthy students. Three stimuli were used： real hand actions, hand shadow actions and actions made by line drawings of hands. The results showed significant desynchronization of the mu rhythm （＂mu suppression＂） across the sensodmotor cortex （recorded at C3, Cz and C4）, the frontal cortex （recorded at F3, Fz and F4） and the central and right posterior parietal cortex （recorded at Pz and P4） under all three conditions. Our experimental findings suggest that the observation of ＂impoverished hand actions＂, such as intransitive movements of shadows and line drawings of hands, is able to activate widespread cortical areas related to the putative human mirror neuron system.展开更多
In this paper, the application of bluetooth in vehicle hands free system was described, then the hardware and software structure of system had been designed. Finally, selection about electron parts and chip of electro...In this paper, the application of bluetooth in vehicle hands free system was described, then the hardware and software structure of system had been designed. Finally, selection about electron parts and chip of electronic equipments was presented in detail.展开更多
Many applications require the solution of large nonsymmetric linear systems with multiple right hand sides. Instead of applying an iterative method to each of these systems individually, it is often more efficient to...Many applications require the solution of large nonsymmetric linear systems with multiple right hand sides. Instead of applying an iterative method to each of these systems individually, it is often more efficient to use a block version of the method that generates iterates for all the systems simultaneously. In this paper, we propose a block version of generalized minimum backward (GMBACK) for solving large multiple nonsymmetric linear systems. The new method employs the block Arnoldi process to construct a basis for the Krylov subspace K m(A, R 0) and seeks X m∈X 0+K m(A, R 0) to minimize the norm of the perturbation to the data given in A.展开更多
Hand Gesture Recognition(HGR)is a promising research area with an extensive range of applications,such as surgery,video game techniques,and sign language translation,where sign language is a complicated structured for...Hand Gesture Recognition(HGR)is a promising research area with an extensive range of applications,such as surgery,video game techniques,and sign language translation,where sign language is a complicated structured form of hand gestures.The fundamental building blocks of structured expressions in sign language are the arrangement of the fingers,the orientation of the hand,and the hand’s position concerning the body.The importance of HGR has increased due to the increasing number of touchless applications and the rapid growth of the hearing-impaired population.Therefore,real-time HGR is one of the most effective interaction methods between computers and humans.Developing a user-free interface with good recognition performance should be the goal of real-time HGR systems.Nowadays,Convolutional Neural Network(CNN)shows great recognition rates for different image-level classification tasks.It is challenging to train deep CNN networks like VGG-16,VGG-19,Inception-v3,and Efficientnet-B0 from scratch because only some significant labeled image datasets are available for static hand gesture images.However,an efficient and robust hand gesture recognition system of sign language employing finetuned Inception-v3 and Efficientnet-Bo network is proposed to identify hand gestures using a comparative small HGR dataset.Experiments show that Inception-v3 achieved 90%accuracy and 0.93%precision,0.91%recall,and 0.90%f1-score,respectively,while EfficientNet-B0 achieved 99%accuracy and 0.98%,0.97%,0.98%,precision,recall,and f1-score respectively.展开更多
Voluntary participation of hemiplegic patients is crucial for functional electrical stimulation therapy.A wearable functional electrical stimulation system has been proposed for real-time volitional hand motor functio...Voluntary participation of hemiplegic patients is crucial for functional electrical stimulation therapy.A wearable functional electrical stimulation system has been proposed for real-time volitional hand motor function control using the electromyography bridge method.Through a series of novel design concepts,including the integration of a detecting circuit and an analog-to-digital converter,a miniaturized functional electrical stimulation circuit technique,a low-power super-regeneration chip for wireless receiving,and two wearable armbands,a prototype system has been established with reduced size,power,and overall cost.Based on wrist joint torque reproduction and classification experiments performed on six healthy subjects,the optimized surface electromyography thresholds and trained logistic regression classifier parameters were statistically chosen to establish wrist and hand motion control with high accuracy.Test results showed that wrist flexion/extension,hand grasp,and finger extension could be reproduced with high accuracy and low latency.This system can build a bridge of information transmission between healthy limbs and paralyzed limbs,effectively improve voluntary participation of hemiplegic patients,and elevate efficiency of rehabilitation training.展开更多
This paper proposes an immersive training system for patients with hand dysfunction who can perform rehabilitation training independently. The system uses Leap Motion binocular vision sensors to collect human hand inf...This paper proposes an immersive training system for patients with hand dysfunction who can perform rehabilitation training independently. The system uses Leap Motion binocular vision sensors to collect human hand information, and uses the improved PCA<sub><img src="Edit_d6662636-9073-4fbd-855f-9a36e871d5a4.png" width="10" height="15" alt="" /></sub> (Principal Component Analysis) to perform data fusion on the real-time data collected by the sensor to obtain more hands with fewer principal components, and improve the stability and accuracy of the data. Immediately, the use of improved SVM<sub><img src="Edit_10c78725-e09e-4dcf-ae05-e21205df4acc.png" width="10" height="15" alt="" /></sub> (Support Vector Machine) and KNN<sub><img src="Edit_0ee97f55-2773-4b48-93b3-93f61aa25577.png" width="10" height="15" alt="" /></sub> (K-Nearest Neighbor Algorithm) for gesture recognition and classification is proposed to enable patients to perform rehabilitation training more effectively. Finally, the effective evaluation results of the rehabilitation effect of patients by the idea of AHP<sub><img src="Edit_70dd1964-28be-4137-afa5-9a184704f08e.png" width="10" height="15" alt="" /></sub> (Analytic Hierarchy Process) are taken as necessary reference factors for doctors to follow up treatment. Various experimental results show that the system has achieved the expected results and has a good application prospect.展开更多
This paper discusses the coordination process for a robot gripper to approach a movingobject with feedback from an uncalibrated visual system. The dynamic of the whole system, includingtarget's random motion and t...This paper discusses the coordination process for a robot gripper to approach a movingobject with feedback from an uncalibrated visual system. The dynamic of the whole system, includingtarget's random motion and the gripper's tracking motion, is bounded to a 2-D working plane. Acamera, whose relations with the robot system and the 2-D working plane are unknown to the robotcontroller, is fixed aside to observe the object and gripper positions continually. Thus the movementsof the robot gripper can be decided on the positions of the object observed in each visual samplingmoment. The coordination of the vision and robot system is to be shown independently from therelations between the robot and the vision system, which should always be calibrated a prior forthe control of traditional robot/vision coordination system. Simulations are provided to show theproperty of the proposed method.展开更多
In this research work,an efficient sign language recognition tool for e-learning has been proposed with a new type of feature set based on angle and lines.This feature set has the ability to increase the overall perfo...In this research work,an efficient sign language recognition tool for e-learning has been proposed with a new type of feature set based on angle and lines.This feature set has the ability to increase the overall performance of machine learning algorithms in an efficient way.The hand gesture recognition based on these features has been implemented for usage in real-time.The feature set used hand landmarks,which were generated using media-pipe(MediaPipe)and open computer vision(openCV)on each frame of the incoming video.The overall algorithm has been tested on two well-known ASLalphabet(American Sign Language)and ISL-HS(Irish Sign Language)sign language datasets.Different machine learning classifiers including random forest,decision tree,and naïve Bayesian have been used to classify hand gestures using this unique feature set and their respective results have been compared.Since the random forest classifier performed better,it has been selected as the base classifier for the proposed system.It showed 96.7%accuracy with ISL-HS and 93.7%accuracy with ASL-alphabet dataset using the extracted features.展开更多
Welding seam tracking precision was decreased due to human hand tremor during the master-slave welding teleoperation. To solve this problem, a master-slave robot remote welding system was built, the system consisted o...Welding seam tracking precision was decreased due to human hand tremor during the master-slave welding teleoperation. To solve this problem, a master-slave robot remote welding system was built, the system consisted of a master manipulator with six degree of freedom （ DOF ） , an industrial computer control system and a slave Motoman HP3 J robot, and human hand tremor and digital filtering were discussed. An optimal digital filter was designed to clean human tremor signal for improving the welding seam tracking precision. The experimental results show that the digital filter suppresses the operator＇ s tremor signal.展开更多
Equations that can predict worsted fabrics’ properties such as bending, shearing, compression, surface and tension, were achieved by means of theoretical and experimental studies. By combining these equations with Ka...Equations that can predict worsted fabrics’ properties such as bending, shearing, compression, surface and tension, were achieved by means of theoretical and experimental studies. By combining these equations with Kawabata’s hand and silhouette evaluation methods, a software system was established. Then the mechanical properties, hand and silhouette of a fabric can be predicted quickly and accurately in terms of fiber configurations, yarn and fabric structures. The predictive result if unsatisfied can be revised by the function of “Help for designing modification”.展开更多
Different micro needle system therapies have different advantages and characteristics.However,at present,the dominant diseases for which each therapy is appropriate are positioned relatively vaguely,and even the acupo...Different micro needle system therapies have different advantages and characteristics.However,at present,the dominant diseases for which each therapy is appropriate are positioned relatively vaguely,and even the acupoint selections for the same disease are different.The clinical application of the dominant disease and application characteristics of each micro needle system therapy is a scientific problem that needs to be explored urgently.Based on the previous data mining study of the clinical application of auricular acupuncture,scalp acupuncture,abdominal acupuncture,eye acupuncture,wrist-ankle acupuncture,hand acupuncture,the second metacarpal bone lateral needling,facial acupuncture,mouth acupuncture and nose acupuncture,the diseases reported more in the clinical literature of each therapy were extracted to find out the same symptoms applicable to different micro needle systems.The clinical application and differences of different micro needle systems for the same disease were compared horizontally,and it demonstrated that the second metacarpal bone lateral needling,facial needle,mouth acupuncture and nose acupuncture were biased towards a partial corresponding therapeutic relationship between one part and the other part,and the eye acupuncture was biased to interfere with the whole by adjusting the function of the organs,and the auricular,scalp and abdominal needles had the both characteristics,and the wrist-malleolus acupuncture and hand acupuncture were often used in various disorders of the meridian-collateral level.The differences were researched and summarized to more accurately guide clinicians in the application of different micro needle system therapies.展开更多
This paper presents a web-based integrated system for on-line sensory fabric hand evaluation. The methods of fuzzy techniques, neural networks, classical factorial analysis and other data analysis are used in the syst...This paper presents a web-based integrated system for on-line sensory fabric hand evaluation. The methods of fuzzy techniques, neural networks, classical factorial analysis and other data analysis are used in the system to analyze the objective and subjective data, and to build the relationship between them. Given the objective data of a new fabric sample, the system can provide its sensory hand data and its total hand grade. In meantime, the total hand grade can be obtained directly from the sensory fabric hand data if provided. The sensory evaluation system is developed in Internet environment using Java language and SQL server database management system.展开更多
文摘Nail changes following upper extremity transplantation(UET)cannot be overlooked as they possess diagnostic and prognostic relevance in allotransplantation of upper limbs.This comprehensive review explores nail and nail bed related changes encountered in UET recipients in the literature.The differential diagnosis of nail abnormalities in UET includes a wide range of systemic,local and iatrogenic conditions other than immune responses to the allograft.It requires interdisciplinary evaluation by primary transplant surgeons,pathologists,dermatologists and immunologists.The possible underlying mechanisms of nail pathology in UET and the management are discussed.It also underscores the importance of onychodystrophy and need for timely intervention and to improve outcomes in UET recipients.
基金supported by European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska Curie grant agreement(No.101028929)BJFis supported by National Heart Foundation of Australia Postdoc-toral Fellowship(No.106588)+1 种基金BG is supported by Australian Government Research Training Program ScholarshipDPLis supported by Clive Kearon Award,McMaster University.Additional funding information can be found in Supplemen-tary Funding.
文摘Background:Muscular strength is a powerful marker of current health status and robust predictor of age-related disease and disability.Handgrip strength(HGS)using isometric dynamometry is a convenient,feasible,and widely used method of assessing muscular strength among people of all ages.While adult HGS norms have been published for many countries,no study has yet synthesized available data to produce international norms.The objective of this study was to generate international sex-and age-specific norms for absolute and body size-normalized HGS across the adult lifespan.Methods:Systematic searches were conducted in 6 databases/web search engines(MEDLINE,SPORTDiscus,Embase,Web of Science,CINAHL,and Google Scholar)up to December 1,2023.We included full-text peer-reviewed observational studies that reported normative HGS data for adults aged ≥20 years by sex and age.Pseudo data were generated using Monte Carlo simulation following harmonization for methodo-logical variation.Population-weighted Generalized Additive Models for Location,Scale,and Shape were used to develop sex-and age-specific norms for absolute HGS(kg)and HGS normalized by height(Ht,m)squared(i.e.,HGS/Ht^(2)in kg/m^(2)).Norms were tabulated as percentile values(5th to 95th)and visualized as smoothed percentile curves.Results:We included data from 100 unique observational studies representing 2,405,863 adults(51.9%female)aged 20 to 100+years from 69 countries and regions tested from the year 2000 onward.On average,absolute and normalized HGS values negligibly improved throughout early adulthood,peaked from age 3039 years(at 49.7 kg(males)and 29.7 kg(females)for absolute HGS or 16.3 kg/m^(2)(males)and 11.3 kg/m^(2)(females)for HGS/Ht^(2)),and declined afterwards.The age-related decline in HGS accelerated from middle to late adulthood and was slightly larger for males than for females during middle adulthood.Conclusion:This study provides the world’s largest and most geographically comprehensive international norms for adult HGS by sex and age.These norms have utility for global peer-comparisons,health screening,and surveillance.
基金Supported by Natural Science Foundation of Ningxia Hui Autonomous Region(NZ0932)National Key Technology R & D Program of China(20068AI06A15-11)~~
文摘[Objective] The purpose of this study was to clarify the structure,growth pattern and histochemical localization of alkaloids in root system of Aconitum flavum Hand.-Mazz.[Method] Paraffin sectioning and histochemistry were employed for performing the analysis in this study.[Result] The root system of Aconitum flavum Hand.-Mazz.consists of taproot,lateral root and adventitious root.The primary structure of root system is normal,but secondary structure shows abnormal.The cambium and the extra cambium of taproot form a ＂U＂-shaped secondary vascular bundle and tertiary bundle in abnormal secondary structure.The sieve tube group is made of little sieve tube group which is differentiated from primary phloem and cambium.Meanwhile,the secondary xylem in tuberous root also appears to be a ＂U＂ shape.Parenchyma cells of secondary phloem occupy most of the tuberous root.The sieve tube group of tuberous root is mainly differentiated from parenchyma cell of secondary phloem.[Conclusion] The difference in abnormal secondary structure of taproot and tuberous root are attributed to their varied cambium compose and activity pattern.Alkaloids are mainly accumulated in parenchyma cell of the inside cortex and between bundle in taproot,while parenchyma of secondary phloem and pith in tuberous root.
基金supported by National Natural Science Foundation of China (Grant No. 50975009)
文摘In order to overcome the drawbacks of traditional rehabilitation method,the robot-aided rehabilitation has been widely investigated for the recent years.And the hand rehabilitation robot,as one of the hot research fields,remains many challenging issues to be investigated.This paper presents a new hand exoskeleton system with some novel characteristics.Firstly,both active and passive rehabilitative motions are realized.Secondly,the device is elaborately designed and brings advantages in many aspects.For example,joint motion is accomplished by a parallelogram mechanism and high level motion control is therefore made very simple without the need of complicated kinematics.The adjustable joint limit design ensures that the actual joint angles don＇t exceed the joint range of motion（ROM） and thus the patient safety is guaranteed.This design can fit to the different patients with different joint ROM as well as to the dynamically changing ROM for individual patient.The device can also accommodate to some extent variety of hand sizes.Thirdly,the proposed control strategy simultaneously realizes the position control and force control with the motor driver which only works in force control mode.Meanwhile,the system resistance compensation is preliminary realized and the resisting force is effectively reduced.Some experiments were conducted to verify the proposed system.Experimentally collected data show that the achieved ROM is close to that of a healthy hand and the range of phalange length（ROPL） covers the size of a typical hand,satisfying the size need of regular hand rehabilitation.In order to evaluate the performance when it works as a haptic device in active mode,the equivalent moment of inertia（MOI） of the device was calculated.The results prove that the device has low inertia which is critical in order to obtain good backdrivability.The experiments also show that in the active mode the virtual interactive force is successfully feedback to the finger and the resistance is reduced by one-third;for the passive control mode,the desired trajectory is realized satisfactorily.
基金Supported by National Key Research and Development Program of China(Grant No.2018YFE0125600)Zhejiang Provincial Key Research,Develop-ment Program(Grant No.2021C04015)Natural Science Foundation of Zhejiang(Grant No.LZ23E050005).
文摘Teleoperation can assist people to complete various complex tasks in inaccessible or high-risk environments,in which a wearable hand exoskeleton is one of the key devices.Adequate adaptability would be available to enable the master hand exoskeleton to capture the motion of human fingers and reproduce the contact force between the slave hand and its object.This paper presents a novel finger exoskeleton based on the cascading four-link closed-loop kinematic chain.Each finger has an independent closed-loop kinematic chain,and the angle sensors are used to obtain the finger motion including the flexion/extension and the adduction/abduction.The cable tension is changed by the servo motor to transmit the contact force to the fingers in real time.Based on the finger exoskeleton,an adaptive hand exoskeleton is consequently developed.In addition,the hand exoskeleton is tested in a master-slave system.The experiment results show that the adaptive hand exoskeleton can be worn without any mechanical constraints,and the slave hand can follow the motions of each human finger.The accuracy and the real-time capability of the force reproduction are validated.The proposed adaptive hand exoskeleton can be employed as the master hand to remotely control the humanoid five-fingered dexterous slave hand,thus,enabling the teleoperation system to complete complex dexterous manipulation tasks.
基金This research was funded by Al-Zaytoonah University of Jordan Grant Number(2020-2019/12/11).
文摘Hand veins can be used effectively in biometric recognition since they are internal organs that,in contrast to fingerprints,are robust under external environment effects such as dirt and paper cuts.Moreover,they form a complex rich shape that is unique,even in identical twins,and allows a high degree of freedom.However,most currently employed hand-based biometric systems rely on hand-touch devices to capture images with the desired quality.Since the start of the COVID-19 pandemic,most handbased biometric systems have become undesirable due to their possible impact on the spread of the pandemic.Consequently,new contactless hand-based biometric recognition systems and databases are desired to keep up with the rising hygiene awareness.One contribution of this research is the creation of a database for hand dorsal veins images obtained contact-free with a variation in capturing distance and rotation angle.This database consists of 1548 images collected from 86 participants whose ages ranged from 19 to 84 years.For the other research contribution,a novel geometrical feature extraction method has been developed based on the Curvelet Transform.This method is useful for extracting robust rotation invariance features from vein images.The database attributes and the veins recognition results are analyzed to demonstrate their efficacy.
基金supported by the grants from the National Natural Science Foundation of China,No.60775019,60970062 and 61173116the Research Fund for the Doctoral Program of Higher Education of China,No.201100702110014
文摘Previous studies have demonstrated that hand shadows may activate the motor cortex associated with the mirror neuron system in human brain. However, there is no evidence of activity of the human mirror neuron system during the observation of intransitive movements by shadows and line drawings of hands. This study examined the suppression of electroencephalography mu waves （8-13 Hz） induced by observation of stimuli in 18 healthy students. Three stimuli were used： real hand actions, hand shadow actions and actions made by line drawings of hands. The results showed significant desynchronization of the mu rhythm （＂mu suppression＂） across the sensodmotor cortex （recorded at C3, Cz and C4）, the frontal cortex （recorded at F3, Fz and F4） and the central and right posterior parietal cortex （recorded at Pz and P4） under all three conditions. Our experimental findings suggest that the observation of ＂impoverished hand actions＂, such as intransitive movements of shadows and line drawings of hands, is able to activate widespread cortical areas related to the putative human mirror neuron system.
文摘In this paper, the application of bluetooth in vehicle hands free system was described, then the hardware and software structure of system had been designed. Finally, selection about electron parts and chip of electronic equipments was presented in detail.
文摘Many applications require the solution of large nonsymmetric linear systems with multiple right hand sides. Instead of applying an iterative method to each of these systems individually, it is often more efficient to use a block version of the method that generates iterates for all the systems simultaneously. In this paper, we propose a block version of generalized minimum backward (GMBACK) for solving large multiple nonsymmetric linear systems. The new method employs the block Arnoldi process to construct a basis for the Krylov subspace K m(A, R 0) and seeks X m∈X 0+K m(A, R 0) to minimize the norm of the perturbation to the data given in A.
基金This research work was supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(NRF-2022R1A2C1004657).
文摘Hand Gesture Recognition(HGR)is a promising research area with an extensive range of applications,such as surgery,video game techniques,and sign language translation,where sign language is a complicated structured form of hand gestures.The fundamental building blocks of structured expressions in sign language are the arrangement of the fingers,the orientation of the hand,and the hand’s position concerning the body.The importance of HGR has increased due to the increasing number of touchless applications and the rapid growth of the hearing-impaired population.Therefore,real-time HGR is one of the most effective interaction methods between computers and humans.Developing a user-free interface with good recognition performance should be the goal of real-time HGR systems.Nowadays,Convolutional Neural Network(CNN)shows great recognition rates for different image-level classification tasks.It is challenging to train deep CNN networks like VGG-16,VGG-19,Inception-v3,and Efficientnet-B0 from scratch because only some significant labeled image datasets are available for static hand gesture images.However,an efficient and robust hand gesture recognition system of sign language employing finetuned Inception-v3 and Efficientnet-Bo network is proposed to identify hand gestures using a comparative small HGR dataset.Experiments show that Inception-v3 achieved 90%accuracy and 0.93%precision,0.91%recall,and 0.90%f1-score,respectively,while EfficientNet-B0 achieved 99%accuracy and 0.98%,0.97%,0.98%,precision,recall,and f1-score respectively.
基金supported by the National Natural Science Foundation of China,No.90307013,90707005,61534003the Science&Technology Pillar Program of Jiangsu Province in China,No.BE2013706
文摘Voluntary participation of hemiplegic patients is crucial for functional electrical stimulation therapy.A wearable functional electrical stimulation system has been proposed for real-time volitional hand motor function control using the electromyography bridge method.Through a series of novel design concepts,including the integration of a detecting circuit and an analog-to-digital converter,a miniaturized functional electrical stimulation circuit technique,a low-power super-regeneration chip for wireless receiving,and two wearable armbands,a prototype system has been established with reduced size,power,and overall cost.Based on wrist joint torque reproduction and classification experiments performed on six healthy subjects,the optimized surface electromyography thresholds and trained logistic regression classifier parameters were statistically chosen to establish wrist and hand motion control with high accuracy.Test results showed that wrist flexion/extension,hand grasp,and finger extension could be reproduced with high accuracy and low latency.This system can build a bridge of information transmission between healthy limbs and paralyzed limbs,effectively improve voluntary participation of hemiplegic patients,and elevate efficiency of rehabilitation training.
文摘This paper proposes an immersive training system for patients with hand dysfunction who can perform rehabilitation training independently. The system uses Leap Motion binocular vision sensors to collect human hand information, and uses the improved PCA<sub><img src="Edit_d6662636-9073-4fbd-855f-9a36e871d5a4.png" width="10" height="15" alt="" /></sub> (Principal Component Analysis) to perform data fusion on the real-time data collected by the sensor to obtain more hands with fewer principal components, and improve the stability and accuracy of the data. Immediately, the use of improved SVM<sub><img src="Edit_10c78725-e09e-4dcf-ae05-e21205df4acc.png" width="10" height="15" alt="" /></sub> (Support Vector Machine) and KNN<sub><img src="Edit_0ee97f55-2773-4b48-93b3-93f61aa25577.png" width="10" height="15" alt="" /></sub> (K-Nearest Neighbor Algorithm) for gesture recognition and classification is proposed to enable patients to perform rehabilitation training more effectively. Finally, the effective evaluation results of the rehabilitation effect of patients by the idea of AHP<sub><img src="Edit_70dd1964-28be-4137-afa5-9a184704f08e.png" width="10" height="15" alt="" /></sub> (Analytic Hierarchy Process) are taken as necessary reference factors for doctors to follow up treatment. Various experimental results show that the system has achieved the expected results and has a good application prospect.
文摘This paper discusses the coordination process for a robot gripper to approach a movingobject with feedback from an uncalibrated visual system. The dynamic of the whole system, includingtarget's random motion and the gripper's tracking motion, is bounded to a 2-D working plane. Acamera, whose relations with the robot system and the 2-D working plane are unknown to the robotcontroller, is fixed aside to observe the object and gripper positions continually. Thus the movementsof the robot gripper can be decided on the positions of the object observed in each visual samplingmoment. The coordination of the vision and robot system is to be shown independently from therelations between the robot and the vision system, which should always be calibrated a prior forthe control of traditional robot/vision coordination system. Simulations are provided to show theproperty of the proposed method.
基金This research was supported by a Grant(2021R1F1A1063634)of the Basic Science Research Program through the National Research Foundation(NRF)funded by the Ministry of Education,Republic of Korea.
文摘In this research work,an efficient sign language recognition tool for e-learning has been proposed with a new type of feature set based on angle and lines.This feature set has the ability to increase the overall performance of machine learning algorithms in an efficient way.The hand gesture recognition based on these features has been implemented for usage in real-time.The feature set used hand landmarks,which were generated using media-pipe(MediaPipe)and open computer vision(openCV)on each frame of the incoming video.The overall algorithm has been tested on two well-known ASLalphabet(American Sign Language)and ISL-HS(Irish Sign Language)sign language datasets.Different machine learning classifiers including random forest,decision tree,and naïve Bayesian have been used to classify hand gestures using this unique feature set and their respective results have been compared.Since the random forest classifier performed better,it has been selected as the base classifier for the proposed system.It showed 96.7%accuracy with ISL-HS and 93.7%accuracy with ASL-alphabet dataset using the extracted features.
基金This research is supported by National Natural Science Foundation of China （No. 50905043）.
文摘Welding seam tracking precision was decreased due to human hand tremor during the master-slave welding teleoperation. To solve this problem, a master-slave robot remote welding system was built, the system consisted of a master manipulator with six degree of freedom （ DOF ） , an industrial computer control system and a slave Motoman HP3 J robot, and human hand tremor and digital filtering were discussed. An optimal digital filter was designed to clean human tremor signal for improving the welding seam tracking precision. The experimental results show that the digital filter suppresses the operator＇ s tremor signal.
文摘Equations that can predict worsted fabrics’ properties such as bending, shearing, compression, surface and tension, were achieved by means of theoretical and experimental studies. By combining these equations with Kawabata’s hand and silhouette evaluation methods, a software system was established. Then the mechanical properties, hand and silhouette of a fabric can be predicted quickly and accurately in terms of fiber configurations, yarn and fabric structures. The predictive result if unsatisfied can be revised by the function of “Help for designing modification”.
基金Supported by National Natural Science Foundation:81473773
文摘Different micro needle system therapies have different advantages and characteristics.However,at present,the dominant diseases for which each therapy is appropriate are positioned relatively vaguely,and even the acupoint selections for the same disease are different.The clinical application of the dominant disease and application characteristics of each micro needle system therapy is a scientific problem that needs to be explored urgently.Based on the previous data mining study of the clinical application of auricular acupuncture,scalp acupuncture,abdominal acupuncture,eye acupuncture,wrist-ankle acupuncture,hand acupuncture,the second metacarpal bone lateral needling,facial acupuncture,mouth acupuncture and nose acupuncture,the diseases reported more in the clinical literature of each therapy were extracted to find out the same symptoms applicable to different micro needle systems.The clinical application and differences of different micro needle systems for the same disease were compared horizontally,and it demonstrated that the second metacarpal bone lateral needling,facial needle,mouth acupuncture and nose acupuncture were biased towards a partial corresponding therapeutic relationship between one part and the other part,and the eye acupuncture was biased to interfere with the whole by adjusting the function of the organs,and the auricular,scalp and abdominal needles had the both characteristics,and the wrist-malleolus acupuncture and hand acupuncture were often used in various disorders of the meridian-collateral level.The differences were researched and summarized to more accurately guide clinicians in the application of different micro needle system therapies.
基金supported by the joint Sino-French Advanced Research Program(No:PRA-SI-01-05)the National Natural Science Foundation(60004006)from P.R.China.
文摘This paper presents a web-based integrated system for on-line sensory fabric hand evaluation. The methods of fuzzy techniques, neural networks, classical factorial analysis and other data analysis are used in the system to analyze the objective and subjective data, and to build the relationship between them. Given the objective data of a new fabric sample, the system can provide its sensory hand data and its total hand grade. In meantime, the total hand grade can be obtained directly from the sensory fabric hand data if provided. The sensory evaluation system is developed in Internet environment using Java language and SQL server database management system.
