This paper analyzes the reasons for the formation of security problems in mobile agent systems, and analyzes and compares the security mechanisms and security technologies of existing mobile agent systems from the per...This paper analyzes the reasons for the formation of security problems in mobile agent systems, and analyzes and compares the security mechanisms and security technologies of existing mobile agent systems from the perspective of blocking attacks. On this basis, the host protection mobile agent protection technology is selected, and a method to enhance the security protection of mobile agents (referred to as IEOP method) is proposed. The method first encrypts the mobile agent code using the encryption function, and then encapsulates the encrypted mobile agent with the improved EOP protocol IEOP, and then traces the suspicious execution result. Experiments show that using this method can block most malicious attacks on mobile agents, and can protect the integrity and confidentiality of mobile agents, but the increment of mobile agent tour time is not large.展开更多
As accessing computing resources from the remote cloud inherently incurs high end-to-end(E2E)delay for mobile users,cloudlets,which are deployed at the edge of a network,can potentially mitigate this problem.Although ...As accessing computing resources from the remote cloud inherently incurs high end-to-end(E2E)delay for mobile users,cloudlets,which are deployed at the edge of a network,can potentially mitigate this problem.Although some research works focus on allocating workloads among cloudlets,the cloudlet placement aiming to minimize the deployment cost(i.e.,consisting of both the cloudlet cost and average E2E delay cost)has not been addressed effectively so far.The locations and number of cloudlets have a crucial impact on both the cloudlet cost in the network and average E2E delay of users.Therefore,in this paper,we propose the Cost Aware cloudlet PlAcement in moBiLe Edge computing(CAPABLE)strategy,where both the cloudlet cost and average E2E delay are considered in the cloudlet placement.To solve this problem,a Lagrangian heuristic algorithm is developed to achieve the suboptimal solution.After cloudlets are placed in the network,we also design a workload allocation scheme to minimize the E2E delay between users and their cloudlets by considering the user mobility.The performance of CAPABLE has been validated by extensive simulations.展开更多
Mobile devices are effective tools for language learning and have positive effect on the development of language skills,heighten learners’language learning attitudes and motivation,and support learner interaction,col...Mobile devices are effective tools for language learning and have positive effect on the development of language skills,heighten learners’language learning attitudes and motivation,and support learner interaction,collaboration,and the coconstruction of knowledge.In spite of the popularity of mobile dictionaries among students,research on the effect of this app on students’language learning,especially focusing on the students from vocational school in rural area,is still scarce.So the purpose of the current study is probing into the effect of using mobile dictionaries on lower-intermediate students’language learning,focusing on the students from vocational school in rural areas,in contrast to using printed dictionaries.This proposal is arranged as follows:section one presents the research background;section two reviews literatures;section three provides research problems and research design;section four presents data analysis and anticipated results.This proposal ends with conclusions.In term of research aims,a mixed method of quantitative and qualitative will be applied with the main aim of probing the effect of using mobile dictionaries on students’English learning and the opinions of students’on using the mobile dictionaries in English learning.Research methods in the form of quasi-experimental pre-and post-tests,questionnaires,interview will be undertaken to collect data.展开更多
For the purpose of solving optimal control problem of a wall-crawling mobile robot working on spherical containers, we propose the Hamel's formalism for Pontryagin Maximum Principle, which gives a general framewor...For the purpose of solving optimal control problem of a wall-crawling mobile robot working on spherical containers, we propose the Hamel's formalism for Pontryagin Maximum Principle, which gives a general framework for the optimal control of a mechanical system with velocity constraints, especially nonholonomic constraints. The effectiveness of the proposed framework is shown by the simulations for the above problem.展开更多
Decompensated cirrhosis is a condition associated with significant morbidity and mortality. While there have been significant efforts to develop quality metrics that ensure high-value care of these patients, wide vari...Decompensated cirrhosis is a condition associated with significant morbidity and mortality. While there have been significant efforts to develop quality metrics that ensure high-value care of these patients, wide variations in clinical practice exist. In this opinion review, we discuss the quality gap in the care of patients with cirrhosis, including low levels of compliance with recommended cancer screening and other clinical outcome and patient-reported outcome measures. We posit that innovations in telemedicine and mobile health (mHealth) should play a key role in closing the quality gaps in liver disease management. We highlight interventions that have been performed to date in liver disease and heart failurefrom successful teleconsultation interventions in the care of veterans with cirrhosis to the use of telemonitoring to reduce hospital readmissions and decrease mortality rates in heart failure. Telemedicine and mHealth can effectively address unmet needs in the care of patients with cirrhosis by increasing preventative care, expanding outreach to rural communities, and increasing high-value care. We aim to highlight the benefits of investing in innovative solutions in telemedicine and mHealth to improve care for patients with cirrhosis and create downstream cost savings.展开更多
This paper considers a UAV communication system with mobile edge computing(MEC).We minimize the energy consumption of the whole system via jointly optimizing the UAV’s trajectory and task assignment as well as CPU’s...This paper considers a UAV communication system with mobile edge computing(MEC).We minimize the energy consumption of the whole system via jointly optimizing the UAV’s trajectory and task assignment as well as CPU’s computational speed under the set of resource constrains.To this end,we first derive the energy consumption model of data processing,and then obtain the energy consumption model of fixed-wing UAV’s flight.The optimization problem is mathematically formulated.To address the problem,we first obtain the approximate optimization problem by applying the technique of discrete linear state-space approximation,and then transform the non-convex constraints into convex by using linearization.Furthermore,a concave-convex procedure(CCCP)based algorithm is proposed in order to solve the optimization problem approximately.Numerical results show the efficacy of the proposed algorithm.展开更多
Hand injuries are a frequent problem in actual society.These are often caused while working or exercising,but simple everyday activities can also be the cause.The most common injuries are those related to soft tissue;...Hand injuries are a frequent problem in actual society.These are often caused while working or exercising,but simple everyday activities can also be the cause.The most common injuries are those related to soft tissue;specifically,muscles,tendons,and ligaments.To improve therapy results and reduce its cost and needed time,a self-rehabilitation system for soft tissue injuries in the hands was developed.The proposed system is meant to be implemented on Smart TVs and can be used in the home of the injured people.To identify the most common movements of the injured limbs,and design proper therapies to be displayed by the system,an exoskeleton prototype which supports four degrees of freedom of the hand was constructed.We examined scenarios to provide services for individuals and created a scenario-based prototype,which was tested by an exercise therapist to verify compliance with the requirements of users.展开更多
Checkbooks can be called the dinosaurs of banking. Once essential for transactions, especially those involving large sums of money, they became virtually extinct with the arrival of ATM cards. Now, as technology conti...Checkbooks can be called the dinosaurs of banking. Once essential for transactions, especially those involving large sums of money, they became virtually extinct with the arrival of ATM cards. Now, as technology continues to evolve, it could be time to say goodbye to the handy little bankcards as well.展开更多
The control problem of a class of parabolic distributed parameter systems (DPSs) is investigated by using mobile agents with capabilities of sensing and actuating. The guidance strategies of mobile agents based on cov...The control problem of a class of parabolic distributed parameter systems (DPSs) is investigated by using mobile agents with capabilities of sensing and actuating. The guidance strategies of mobile agents based on coverage optimization methods are proposed to improve the control performance of the system and make the state norm of the system converge to zero faster. The coverage optimization problems are constructed based on the measurement of each agent. By solving the coverage optimization problems, the local optimal moving direction of each agent can be obtained. Then the gradient-based agent motion control laws are established. With the indicator function and the surface delta function, this method is generalized to n-dimensional space, and suitable for any sensing region with piecewise smooth boundaries. The stability and control performance of the system are analyzed. Numerical simulations show the effectiveness of the proposed methods.展开更多
Background: The universal goniometer is commonly used to measure knee range of movement in clinical practice. However, research has demonstrated that the universal goniometer lacks reliability failing to meet the stan...Background: The universal goniometer is commonly used to measure knee range of movement in clinical practice. However, research has demonstrated that the universal goniometer lacks reliability failing to meet the standard of clinically acceptable error (5°). Objective: This study tested the concurrent validity and intra-rater reliability of a photographic based “app” developed for feedback in sport, the Hudl Ubersense App, as an alternative instrument for measuring knee range of movement. Methods: Measurements of knee range of movement were made concurrently with the electrogoniometer (the gold standard) and the Hudl Ubersense App across a pre-determined randomised set of 20 functional knee angles between 35° and 130°. This was then repeated. The pre-agreed standard of concurrent validity was that 95% of Hudl Ubersense App measurements would be within 5° of the electrogoniometer and differences were displayed in Bland-Altman plots. Results: Thirty nine (97%) of the forty app readings differed from the corresponding electrogoniometer readings by less than 5°. The mean differences between the electrogoniometer and Hudl Ubersense App measurements over each trial were 1.75° and 0.80° respectively, indicating a high level of concurrent validity. There was less than 1.0° mean difference between the first and second set of results indicating a high level of intra-rater reliability. Conclusions: The results suggest that the Hudl Ubersense App has high levels of concurrent validity (using the electrogoniometer as the gold standard) and intra-rater reliability, scoring better than previous research on the current clinical measuring device, the universal goniometer. The Hudl Ubersense App has clinical advantages over the electrogoniometer, so further research is recommended to determine its inter-rater reliability, acceptability, and appropriate clinical practice procedures.展开更多
Mobile edge computing(MEC) provides a fresh opportunity to significantly reduce the latency and battery energy consumption of mobile applications. It does so by enabling the offloading of parts of the applications on ...Mobile edge computing(MEC) provides a fresh opportunity to significantly reduce the latency and battery energy consumption of mobile applications. It does so by enabling the offloading of parts of the applications on mobile edges, which are located in close proximity to the mobile devices. Owing to the geographical distribution of mobile edges and the mobility of mobile devices, the runtime environment of MEC is highly complex and dynamic. As a result, it is challenging for application developers to support computation offloading in MEC compared with the traditional approach in mobile cloud computing, where applications use only the cloud for offloading. On the one hand, developers have to make the offloading adaptive to the changing environment, where the offloading should dynamically occur among available computation nodes.On the other hand, developers have to effectively determine the offloading scheme each time the environment changes. To address these challenges, this paper proposes an adaptive framework that supports mobile applications with offloading capabilities in MEC. First, based on our previous study(DPartner), a new design pattern is proposed to enable an application to be dynamically offloaded among mobile devices, mobile edges,and the cloud. Second, an estimation model is designed to automatically determine the offloading scheme.In this model, different parts of the application may be executed on different computation nodes. Finally, an adaptive offloading framework is implemented to support the design pattern and the estimation model. We evaluate our framework on two real-world applications. The results demonstrate that our approach can aid in reducing the response time by 8%–50% and energy consumption by 9%–51% for computation-intensive applications.展开更多
When the mobile robot performs certain motion tasks in complex environment, wheel slipping inevitably occurs due to the wet or icy road and other reasons, thus directly influences the motion control accuracy. To addre...When the mobile robot performs certain motion tasks in complex environment, wheel slipping inevitably occurs due to the wet or icy road and other reasons, thus directly influences the motion control accuracy. To address unknown wheel longitudinal slipping problem for mobile robot, a RBF neural network approach based on whole model approximation is presented. The real-time data acquisition of inertial measure unit(IMU), encoders and other sensors is employed to get the mobile robot’s position and orientation in the movement, which is applied to compensate the unknown bounds of the longitudinal slipping using the adaptive technique. Both the simulation and experimental results prove that the control scheme possesses good practical performance and realize the motion control with unknown longitudinal slipping.展开更多
The world is steadily moving to the post-liberal order with the urgent need of novel organizational and security approaches,also new levels of international cooperation,in order to support its stability and prosperity...The world is steadily moving to the post-liberal order with the urgent need of novel organizational and security approaches,also new levels of international cooperation,in order to support its stability and prosperity.The developed high-level Spatial Grasp Technology(SGT)and its Spatial Grasp Language(SGL)are briefed which may be particularly useful for solving numerous conflicts and crises problems emerging in different areas during this transitional period,in both local and global scale.SGT employs unlimited spatial scenario mobility and parallel holistic matching of distributed systems,with numerous communicating SGL interpreters potentially installed worldwide.Basic network creation and management operations are described in SGL which may operate on top of existing communication systems or serve individually as high level network protocols in case of non-local crises and disasters.Different operations on social networks are presented in SGL including finding strongest and weakest components with resultant changing of network topologies,also determining distances between different communities for preventing and predicting social conflicts.Fully distributed analysis,and tracing and simulation of multiple mobile objects in distributed spaces with complex routes are shown in SGL related to cruise missiles,defence objects and debris in outer space,as well as massively moving refugees through international borders.The proposed technology had trial implementations and applications in different countries,and its latest version can be readily installed by agreement on any platforms needed.展开更多
Autonomous navigation of a mobile robot in an unknown environment with highly cluttered obstacles is a fundamental issue in mobile robotics research. We propose an adaptive network fuzzy inference system(ANFIS) based ...Autonomous navigation of a mobile robot in an unknown environment with highly cluttered obstacles is a fundamental issue in mobile robotics research. We propose an adaptive network fuzzy inference system(ANFIS) based navigation controller for a differential drive mobile robot in an unknown environment with cluttered obstacles. Ultrasonic sensors are used to capture the environmental information around the mobile robot. A training data set required to train the ANFIS controller has been obtained by designing a fuzzy logic based navigation controller. Additive white Gaussian noise has been added to the sensor readings and fed to the trained ANFIS controller during mobile robot navigation, to account for the effect of environmental noise on sensor readings. The robustness of the proposed navigation controller has been evaluated by navigating the mobile robot in three different environments. The performance of the proposed controller has been verified by comparing the travelled path length/efficiency and bending energy obtained by the proposed method with reference mobile robot navigation controllers, such as neural network, fuzzy logic, and ANFIS. Simulation results presented in this paper show that the proposed controller has better performance compared with reference controllers and can successfully navigate in different environments without any collision with obstacles.展开更多
This paper proposes an intelligent controller for motion control of robotic systems to obtain high precision tracking without the need for a real-time trial and error method.In addition, a new self-tuning algorithm ha...This paper proposes an intelligent controller for motion control of robotic systems to obtain high precision tracking without the need for a real-time trial and error method.In addition, a new self-tuning algorithm has been developed based on both the ant colony algorithm and a fuzzy system for real-time tuning of controller parameters. Simulations and experiments using a real robot have been addressed to demonstrate the success of the proposed controller and validate the theoretical analysis. Obtained results confirm that the proposed controller ensures robust performance in the presence of disturbances and parametric uncertainties without the need for adjustment of control law parameters by a trial and error method.展开更多
基金the National Natural Science Foundation of China (6177219661472136)+3 种基金the Hunan Provincial Focus Social Science Fund (2016ZDB006)Hunan Provincial Social Science Achievement Review Committee results appraisal identification project (Xiang social assessment 2016JD05)Key Project of Hunan Provincial Social Science Achievement Review Committee (XSP 19ZD1005)the Key Laboratory of Hunan Province for New Retail Virtual Reality Technology (2017TP1026).
文摘This paper analyzes the reasons for the formation of security problems in mobile agent systems, and analyzes and compares the security mechanisms and security technologies of existing mobile agent systems from the perspective of blocking attacks. On this basis, the host protection mobile agent protection technology is selected, and a method to enhance the security protection of mobile agents (referred to as IEOP method) is proposed. The method first encrypts the mobile agent code using the encryption function, and then encapsulates the encrypted mobile agent with the improved EOP protocol IEOP, and then traces the suspicious execution result. Experiments show that using this method can block most malicious attacks on mobile agents, and can protect the integrity and confidentiality of mobile agents, but the increment of mobile agent tour time is not large.
文摘As accessing computing resources from the remote cloud inherently incurs high end-to-end(E2E)delay for mobile users,cloudlets,which are deployed at the edge of a network,can potentially mitigate this problem.Although some research works focus on allocating workloads among cloudlets,the cloudlet placement aiming to minimize the deployment cost(i.e.,consisting of both the cloudlet cost and average E2E delay cost)has not been addressed effectively so far.The locations and number of cloudlets have a crucial impact on both the cloudlet cost in the network and average E2E delay of users.Therefore,in this paper,we propose the Cost Aware cloudlet PlAcement in moBiLe Edge computing(CAPABLE)strategy,where both the cloudlet cost and average E2E delay are considered in the cloudlet placement.To solve this problem,a Lagrangian heuristic algorithm is developed to achieve the suboptimal solution.After cloudlets are placed in the network,we also design a workload allocation scheme to minimize the E2E delay between users and their cloudlets by considering the user mobility.The performance of CAPABLE has been validated by extensive simulations.
文摘Mobile devices are effective tools for language learning and have positive effect on the development of language skills,heighten learners’language learning attitudes and motivation,and support learner interaction,collaboration,and the coconstruction of knowledge.In spite of the popularity of mobile dictionaries among students,research on the effect of this app on students’language learning,especially focusing on the students from vocational school in rural area,is still scarce.So the purpose of the current study is probing into the effect of using mobile dictionaries on lower-intermediate students’language learning,focusing on the students from vocational school in rural areas,in contrast to using printed dictionaries.This proposal is arranged as follows:section one presents the research background;section two reviews literatures;section three provides research problems and research design;section four presents data analysis and anticipated results.This proposal ends with conclusions.In term of research aims,a mixed method of quantitative and qualitative will be applied with the main aim of probing the effect of using mobile dictionaries on students’English learning and the opinions of students’on using the mobile dictionaries in English learning.Research methods in the form of quasi-experimental pre-and post-tests,questionnaires,interview will be undertaken to collect data.
基金the National Natural Science Foundation of China (Grant 11872107) for support.
文摘For the purpose of solving optimal control problem of a wall-crawling mobile robot working on spherical containers, we propose the Hamel's formalism for Pontryagin Maximum Principle, which gives a general framework for the optimal control of a mechanical system with velocity constraints, especially nonholonomic constraints. The effectiveness of the proposed framework is shown by the simulations for the above problem.
文摘Decompensated cirrhosis is a condition associated with significant morbidity and mortality. While there have been significant efforts to develop quality metrics that ensure high-value care of these patients, wide variations in clinical practice exist. In this opinion review, we discuss the quality gap in the care of patients with cirrhosis, including low levels of compliance with recommended cancer screening and other clinical outcome and patient-reported outcome measures. We posit that innovations in telemedicine and mobile health (mHealth) should play a key role in closing the quality gaps in liver disease management. We highlight interventions that have been performed to date in liver disease and heart failurefrom successful teleconsultation interventions in the care of veterans with cirrhosis to the use of telemonitoring to reduce hospital readmissions and decrease mortality rates in heart failure. Telemedicine and mHealth can effectively address unmet needs in the care of patients with cirrhosis by increasing preventative care, expanding outreach to rural communities, and increasing high-value care. We aim to highlight the benefits of investing in innovative solutions in telemedicine and mHealth to improve care for patients with cirrhosis and create downstream cost savings.
基金National Natural Science Foundation of China(Grant No.61702149,U1709220).
文摘This paper considers a UAV communication system with mobile edge computing(MEC).We minimize the energy consumption of the whole system via jointly optimizing the UAV’s trajectory and task assignment as well as CPU’s computational speed under the set of resource constrains.To this end,we first derive the energy consumption model of data processing,and then obtain the energy consumption model of fixed-wing UAV’s flight.The optimization problem is mathematically formulated.To address the problem,we first obtain the approximate optimization problem by applying the technique of discrete linear state-space approximation,and then transform the non-convex constraints into convex by using linearization.Furthermore,a concave-convex procedure(CCCP)based algorithm is proposed in order to solve the optimization problem approximately.Numerical results show the efficacy of the proposed algorithm.
文摘Hand injuries are a frequent problem in actual society.These are often caused while working or exercising,but simple everyday activities can also be the cause.The most common injuries are those related to soft tissue;specifically,muscles,tendons,and ligaments.To improve therapy results and reduce its cost and needed time,a self-rehabilitation system for soft tissue injuries in the hands was developed.The proposed system is meant to be implemented on Smart TVs and can be used in the home of the injured people.To identify the most common movements of the injured limbs,and design proper therapies to be displayed by the system,an exoskeleton prototype which supports four degrees of freedom of the hand was constructed.We examined scenarios to provide services for individuals and created a scenario-based prototype,which was tested by an exercise therapist to verify compliance with the requirements of users.
文摘Checkbooks can be called the dinosaurs of banking. Once essential for transactions, especially those involving large sums of money, they became virtually extinct with the arrival of ATM cards. Now, as technology continues to evolve, it could be time to say goodbye to the handy little bankcards as well.
基金supported by the National Natural Science Foundation of China(6180701661174021)+3 种基金the Fundamental Research Funds for the Central Universities(JUSRP115A28JUSRP51733B)the 111 Projeet(B12018)the Postgraduate Innovation Project of Jiangsu Province(KYLX151170).
文摘The control problem of a class of parabolic distributed parameter systems (DPSs) is investigated by using mobile agents with capabilities of sensing and actuating. The guidance strategies of mobile agents based on coverage optimization methods are proposed to improve the control performance of the system and make the state norm of the system converge to zero faster. The coverage optimization problems are constructed based on the measurement of each agent. By solving the coverage optimization problems, the local optimal moving direction of each agent can be obtained. Then the gradient-based agent motion control laws are established. With the indicator function and the surface delta function, this method is generalized to n-dimensional space, and suitable for any sensing region with piecewise smooth boundaries. The stability and control performance of the system are analyzed. Numerical simulations show the effectiveness of the proposed methods.
基金The authors would like to express their thanks to Roy Petticrew (senior technician for the CU School of Health and Life Sciences) for his time and expertise in conducting the study. Author Sara Aspinall completed this work as part of an MSc by research supported by the National Institute for Health Research (NIHR). This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.
文摘Background: The universal goniometer is commonly used to measure knee range of movement in clinical practice. However, research has demonstrated that the universal goniometer lacks reliability failing to meet the standard of clinically acceptable error (5°). Objective: This study tested the concurrent validity and intra-rater reliability of a photographic based “app” developed for feedback in sport, the Hudl Ubersense App, as an alternative instrument for measuring knee range of movement. Methods: Measurements of knee range of movement were made concurrently with the electrogoniometer (the gold standard) and the Hudl Ubersense App across a pre-determined randomised set of 20 functional knee angles between 35° and 130°. This was then repeated. The pre-agreed standard of concurrent validity was that 95% of Hudl Ubersense App measurements would be within 5° of the electrogoniometer and differences were displayed in Bland-Altman plots. Results: Thirty nine (97%) of the forty app readings differed from the corresponding electrogoniometer readings by less than 5°. The mean differences between the electrogoniometer and Hudl Ubersense App measurements over each trial were 1.75° and 0.80° respectively, indicating a high level of concurrent validity. There was less than 1.0° mean difference between the first and second set of results indicating a high level of intra-rater reliability. Conclusions: The results suggest that the Hudl Ubersense App has high levels of concurrent validity (using the electrogoniometer as the gold standard) and intra-rater reliability, scoring better than previous research on the current clinical measuring device, the universal goniometer. The Hudl Ubersense App has clinical advantages over the electrogoniometer, so further research is recommended to determine its inter-rater reliability, acceptability, and appropriate clinical practice procedures.
基金National Key R&D Program of China (Grant No. 2017YFB1002000)National Natural Science Foundation of China (Grant No. 61725201)Talent Program of Fujian Province for Distinguished Young Scholars in Higher Education.
文摘Mobile edge computing(MEC) provides a fresh opportunity to significantly reduce the latency and battery energy consumption of mobile applications. It does so by enabling the offloading of parts of the applications on mobile edges, which are located in close proximity to the mobile devices. Owing to the geographical distribution of mobile edges and the mobility of mobile devices, the runtime environment of MEC is highly complex and dynamic. As a result, it is challenging for application developers to support computation offloading in MEC compared with the traditional approach in mobile cloud computing, where applications use only the cloud for offloading. On the one hand, developers have to make the offloading adaptive to the changing environment, where the offloading should dynamically occur among available computation nodes.On the other hand, developers have to effectively determine the offloading scheme each time the environment changes. To address these challenges, this paper proposes an adaptive framework that supports mobile applications with offloading capabilities in MEC. First, based on our previous study(DPartner), a new design pattern is proposed to enable an application to be dynamically offloaded among mobile devices, mobile edges,and the cloud. Second, an estimation model is designed to automatically determine the offloading scheme.In this model, different parts of the application may be executed on different computation nodes. Finally, an adaptive offloading framework is implemented to support the design pattern and the estimation model. We evaluate our framework on two real-world applications. The results demonstrate that our approach can aid in reducing the response time by 8%–50% and energy consumption by 9%–51% for computation-intensive applications.
基金Supported by Scientific and Innovation Research Funds for the Beijing University of Posts and Telecommunications (Grant No. 2017RC22).
文摘When the mobile robot performs certain motion tasks in complex environment, wheel slipping inevitably occurs due to the wet or icy road and other reasons, thus directly influences the motion control accuracy. To address unknown wheel longitudinal slipping problem for mobile robot, a RBF neural network approach based on whole model approximation is presented. The real-time data acquisition of inertial measure unit(IMU), encoders and other sensors is employed to get the mobile robot’s position and orientation in the movement, which is applied to compensate the unknown bounds of the longitudinal slipping using the adaptive technique. Both the simulation and experimental results prove that the control scheme possesses good practical performance and realize the motion control with unknown longitudinal slipping.
文摘The world is steadily moving to the post-liberal order with the urgent need of novel organizational and security approaches,also new levels of international cooperation,in order to support its stability and prosperity.The developed high-level Spatial Grasp Technology(SGT)and its Spatial Grasp Language(SGL)are briefed which may be particularly useful for solving numerous conflicts and crises problems emerging in different areas during this transitional period,in both local and global scale.SGT employs unlimited spatial scenario mobility and parallel holistic matching of distributed systems,with numerous communicating SGL interpreters potentially installed worldwide.Basic network creation and management operations are described in SGL which may operate on top of existing communication systems or serve individually as high level network protocols in case of non-local crises and disasters.Different operations on social networks are presented in SGL including finding strongest and weakest components with resultant changing of network topologies,also determining distances between different communities for preventing and predicting social conflicts.Fully distributed analysis,and tracing and simulation of multiple mobile objects in distributed spaces with complex routes are shown in SGL related to cruise missiles,defence objects and debris in outer space,as well as massively moving refugees through international borders.The proposed technology had trial implementations and applications in different countries,and its latest version can be readily installed by agreement on any platforms needed.
基金the Brain Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science,ICT,and Future Planning(No.NRF-2017M3C7A1044815)Research Base Construction Fund Support Program funded by Chonbuk National University in 2015.
文摘Autonomous navigation of a mobile robot in an unknown environment with highly cluttered obstacles is a fundamental issue in mobile robotics research. We propose an adaptive network fuzzy inference system(ANFIS) based navigation controller for a differential drive mobile robot in an unknown environment with cluttered obstacles. Ultrasonic sensors are used to capture the environmental information around the mobile robot. A training data set required to train the ANFIS controller has been obtained by designing a fuzzy logic based navigation controller. Additive white Gaussian noise has been added to the sensor readings and fed to the trained ANFIS controller during mobile robot navigation, to account for the effect of environmental noise on sensor readings. The robustness of the proposed navigation controller has been evaluated by navigating the mobile robot in three different environments. The performance of the proposed controller has been verified by comparing the travelled path length/efficiency and bending energy obtained by the proposed method with reference mobile robot navigation controllers, such as neural network, fuzzy logic, and ANFIS. Simulation results presented in this paper show that the proposed controller has better performance compared with reference controllers and can successfully navigate in different environments without any collision with obstacles.
文摘This paper proposes an intelligent controller for motion control of robotic systems to obtain high precision tracking without the need for a real-time trial and error method.In addition, a new self-tuning algorithm has been developed based on both the ant colony algorithm and a fuzzy system for real-time tuning of controller parameters. Simulations and experiments using a real robot have been addressed to demonstrate the success of the proposed controller and validate the theoretical analysis. Obtained results confirm that the proposed controller ensures robust performance in the presence of disturbances and parametric uncertainties without the need for adjustment of control law parameters by a trial and error method.