To serve various tasks requested by various end devices with different requirements,end-edge-cloud(E2C)has attracted more and more attention from specialists in both academia and industry,by combining both benefits of...To serve various tasks requested by various end devices with different requirements,end-edge-cloud(E2C)has attracted more and more attention from specialists in both academia and industry,by combining both benefits of edge and cloud computing.But nowadays,E2C still suffers from low service quality and resource efficiency,due to the geographical distribution of edge resources and the high dynamic of network topology and user mobility.To address these issues,this paper focuses on task offloading,which makes decisions that which resources are allocated to tasks for their processing.This paper first formulates the problem into binary non-linear programming and then proposes a particle swarm optimization(PSO)-based algorithm to solve the problem.The proposed algorithm exploits an imbalance mutation operator and a task rescheduling approach to improve the performance of PSO.The proposed algorithm concerns the resource heterogeneity by correlating the probability that a computing node is decided to process a task with its capacity,by the imbalance mutation.The task rescheduling approach improves the acceptance ratio for a task offloading solution,by reassigning rejected tasks to computing nodes with available resources.Extensive simulated experiments are conducted.And the results show that the proposed offloading algorithm has an 8.93%–37.0%higher acceptance ratio than ten of the classical and up-to-date algorithms,and verify the effectiveness of the imbalanced mutation and the task rescheduling.展开更多
In the age of information sharing, logistics information sharing also faces the risk of privacy leakage. In regard to the privacy leakage of time-series location information in the field of logistics, this paper propo...In the age of information sharing, logistics information sharing also faces the risk of privacy leakage. In regard to the privacy leakage of time-series location information in the field of logistics, this paper proposes a method based on differential privacy for time-series location data publication. Firstly, it constructs public region of interest(PROI) related to time by using clustering optimal algorithm. And it adopts the method of the centroid point to ensure the public interest point(PIP) representing the location of the public interest zone. Secondly, according to the PIP, we can construct location search tree(LST) that is a commonly used index structure of spatial data, in order to ensure the inherent relation among location data. Thirdly, we add Laplace noise to the node of LST, which means fewer times to add Laplace noise on the original data set and ensures the data availability. Finally, experiments show that this method not only ensures the security of sequential location data publishing, but also has better data availability than the general differential privacy method, which achieves a good balance between the security and availability of data.展开更多
Seismic geophone is the key instrument for seismic data acquisition in the fields of oil and gas exploration and other relevant fields.It plays an important role in data quality,subsequent processing and interpretatio...Seismic geophone is the key instrument for seismic data acquisition in the fields of oil and gas exploration and other relevant fields.It plays an important role in data quality,subsequent processing and interpretation.Aiming at the shortcomings of the existing geophones,such as large volume,heavy weight,unable to monitor in real-time,and heavy workload of data transmission and storage,this paper designs and implements a wireless geophone based on STM32 embedded microcontroller.It is mainly composed of STM32 microcontroller,acceleration sensor,global positioning system(GPS)module,Wi-Fi module and real-time seismic data receiving and processing module.Firstly,the acceleration of vibration in three directions is sensed by the acceleration sensor;secondly,the sampling and analog-to-digital conversion of the vibration data is controlled by the microcontroller;thirdly,the vibration and GPS data are sent to the personal computer(PC)through Wi-Fi,and the personal coomputer PC-side software module completes the reception,display,monitoring and storage of the seismic data;finally,the feasibility and effectiveness of the designed wireless geophone are verified through actual seismic data acquisition experiments.展开更多
Aiming at the problems of low accuracy,long time consumption,and failure to obtain quantita-tive fault identification results of existing automatic fault identification technic,a fault recognition method based on clus...Aiming at the problems of low accuracy,long time consumption,and failure to obtain quantita-tive fault identification results of existing automatic fault identification technic,a fault recognition method based on clustering linear regression is proposed.Firstly,Hough transform is used to detect the line segment of the enhanced image obtained by the coherence cube algorithm.Secondly,the endpoint of the line segment detected by Hough transform is taken as the key point,and the adaptive clustering linear regression algorithm is used to cluster the key points adaptively according to the lin-ear relationship between them.Finally,a fault is generated from each category of key points based on least squares curve fitting method to realize fault identification.To verify the feasibility and pro-gressiveness of the proposed method,it is compared with the traditional method and the latest meth-od on the actual seismic data through experiments,and the effectiveness of the proposed method is verified by the experimental results on the actual seismic data.展开更多
In order to quickly and accurately find the implementer of the network crime,based on the user portrait technology,a rapid detection method for users with abnormal behaviors is proposed.This method needs to construct ...In order to quickly and accurately find the implementer of the network crime,based on the user portrait technology,a rapid detection method for users with abnormal behaviors is proposed.This method needs to construct the abnormal behavior rule base on various kinds of abnormal behaviors in advance,and construct the user portrait including basic attribute tags,behavior attribute tags and abnormal behavior similarity tags for network users who have abnormal behaviors.When a network crime occurs,firstly get the corresponding tag values in all user portraits according to the category of the network crime.Then,use the Naive Bayesian method matching each user portrait,to quickly locate the most likely network criminal suspects.In the case that no suspect is found,all users are audited comprehensively through matching abnormal behavior rule base.The experimental results show that,the accuracy rate of using this method for fast detection of network crimes is 95.9%,and the audit time is shortened to 1/35 of that of the conventional behavior audit method.展开更多
Within the context of Massive Open Online Courses(MOoCs),the application of Human-in-the-loop systems is becoming increasingly prevalent.Given the issue of high dropout rates in MOoCs,developing accurate dropout predi...Within the context of Massive Open Online Courses(MOoCs),the application of Human-in-the-loop systems is becoming increasingly prevalent.Given the issue of high dropout rates in MOoCs,developing accurate dropout prediction models is essential to improve educational outcomes and ensure the sustainability of the platform.Researchers usually use interactive information between students and platforms to build predictive models.However,existing methods have the problem that the single construction of behavioral characteristics leads to misclassification of special student groups.Therefore,after in-depth analysis of the behavioral data of MOOC learners,this paper constructs the characteristics of learning activity based on the two dimensions of learning time and number of clicks to reduce the misclassification of special groups.On this basis,we propose a hybrid neural network model(CNN-LSTMAE)to model and predict dropout behavior.CNNLSTMAE uses the Convolutional Neural Network(CNN)to extract local features of students'behaviors,and uses the Long-Short-Term Memory Autoencoder(LSTMAE)module to perform a high-level abstract representation of local features.Experimental results on the KDD Cup 2015 dataset show that the proposed model has better predictive performance than the baseline methods.展开更多
With the widespread use of agile software development methods,such as agile and scrum,software is iteratively updated more frequently.To ensure the quality of the software,regression testing is conducted before new ve...With the widespread use of agile software development methods,such as agile and scrum,software is iteratively updated more frequently.To ensure the quality of the software,regression testing is conducted before new versions are released.Moreover,to improve the efficiency of regression testing,testing efforts should be concentrated on the modified and impacted parts of a program.However,the costs of manually constructing new test cases for the modified and impacted parts are relatively expensive.Fuzz testing is an effective method for generating test data automatically,but it is usually devoted to achieving higher code coverage,which makes fuzz testing unsuitable for direct regression testing scenarios.For this reason,we propose a fuzz testing method based on the guidance of historical version information.First,the differences between the program being tested and the last version are analyzed,and the results of the analysis are used to locate change points.Second,change impact analysis is performed to find the corresponding impacted basic blocks.Finally,the fitness values of test cases are calculated according to the execution traces,and new test cases are generated iteratively by the genetic algorithm.Based on the proposed method,we implement a prototype tool DeltaFuzz and conduct experiments on six open-source projects.Compared with the fuzzing tool AFLGo,AFLFast and AFL,DeltaFuzz can reach the target faster,and the time taken by DeltaFuzz was reduced by 20.59%,30.05%and 32.61%,respectively.展开更多
Ancient Chinese characters, typically the ideographic characters on bones and bronze before Shang Dynasty(16th—11th century B.C.), are valuable culture legacy of history. However the recognition of Ancient Chinese ch...Ancient Chinese characters, typically the ideographic characters on bones and bronze before Shang Dynasty(16th—11th century B.C.), are valuable culture legacy of history. However the recognition of Ancient Chinese characters has been the task of paleography experts for long. With the help of modern computer technique, everyone can expect to be able to recognize the characters and understand the ancient inscriptions. This research is aimed to help people recognize and understand those ancient Chinese characters by combining Chinese paleography theory and computer information processing technology. Based on the analysis of ancient character features, a method for structural character recognition is proposed. The important characteristics of strokes and basic components or radicals used in recognition are introduced in detail. A system was implemented based on above method to show the effectiveness of the method.展开更多
Protecting healthcare data privacy and security is crucial in advanced manufacturing,which involves medical devices.It encompasses patient records and clinical trial data.Federated learning emerges as a solution that ...Protecting healthcare data privacy and security is crucial in advanced manufacturing,which involves medical devices.It encompasses patient records and clinical trial data.Federated learning emerges as a solution that enables model training across different institutions without compromising data privacy and security.However,existing frameworks often exhibit a bias towards clients with larger data volumes,neglecting the connection between global and local model performance.This can result in suboptimal aggregation of the global model,thereby affecting the effectiveness and efficiency of the overall process.To address these limitations,we propose a performance evaluation-driven federated learning framework(PedFed).The primary objective of PedFed is to enhance global model aggregation and improve communication efficiency.Our approach involves a client selection strategy based on performance evaluation of local and global models.Specifically,we introduce the concept of local model improvement(LMI)using Intersection over Union(IoU)for client selection in medical image segmentation scenarios.Moreover,we introduce a dynamic aggregation framework incorporating validation IoU as a weighting factor to mitigate model divergence caused by not independent and identically distributed(non-IID)data.We focus on performing image segmentation tasks to simulate the analysis of sensitive data in the healthcare domain.Experimental results conducted on brain tumor and heart segmentation datasets demonstrate the superiority of the PedFed framework over the baseline framework,confirming its benefits in communication efficiency.展开更多
Mobile edge computing(MEC),as a new distributed computing model,satisfies the low energy consumption and low latency requirements of computation-intensive services.The task offloading of MEC has become an important re...Mobile edge computing(MEC),as a new distributed computing model,satisfies the low energy consumption and low latency requirements of computation-intensive services.The task offloading of MEC has become an important research hotspot,as it solves the problems of insufficient computing capability and battery capacity of Internet of things(IoT)devices.This study investigates task offloading scheduling in a dynamic MEC system.By integrating energy harvesting technology into IoT devices,we propose a hybrid energy supply model.We jointly optimize local computing,offloading duration,and edge computing decisions to minimize system cost.On the basis of stochastic optimization theory,we design an online dynamic task offloading algorithm for MEC with a hybrid energy supply called DTOME.DTOME can make task offloading decisions by weighing system cost and queue stability.We quote dynamic programming theory to obtain the optimal task offloading strategy.Simulation results verify the effectiveness of DTOME,and show that DTOME entails lower system cost than two baseline task offloading strategies.展开更多
The technology of Ultra-High Voltage (UHV) transmission requires higher dependability for electric power grid. Power Grid Communication Networking (PGCN), the fundamental information infrastructure, severs data tr...The technology of Ultra-High Voltage (UHV) transmission requires higher dependability for electric power grid. Power Grid Communication Networking (PGCN), the fundamental information infrastructure, severs data transmission including control signal, protection signal, and common data services. Dependability is the necessary requirement to ensure services timely and accurately. Dependability analysis aims to predicate operation status and provide suitable strategies getting rid of the potential dangers. Due to the dependability of PGCN may be affected by external environment, devices quality, implementation strategies, and so on, the scale explosion and the structure complexity make the PGCN's dependability much challenging. In this paper, with the observation of interdependency between power grid and PGCN, we propose an electricity services based dependability analysis model of PGCN. The model includes methods of analyzing its dependability and procedures of designing the dependable strategies. We respectively discuss the deterministic analysis method based on matrix analysis and stochastic analysis model based on stochastic Petri nets.展开更多
In current software defect prediction (SDP) research, most previous empirical studies only use datasets provided by PROMISE repository and this may cause a threat to the external validity of previous empirical results...In current software defect prediction (SDP) research, most previous empirical studies only use datasets provided by PROMISE repository and this may cause a threat to the external validity of previous empirical results. Instead of SDP dataset sharing, SDP model sharing is a potential solution to alleviate this problem and can encourage researchers in the research community and practitioners in the industrial community to share more models. However, directly sharing models may result in privacy disclosure, such as model inversion attack. To the best of our knowledge, we are the first to apply differential privacy (DP) to privacy-preserving SDP model sharing and then propose a novel method DP-Share, since DP mechanisms can prevent this attack when the privacy budget is carefully selected. In particular, DP-Share first performs data preprocessing for the dataset, such as over-sampling for minority instances (i.e., defective modules) and conducting discretization for continuous features to optimize privacy budget allocation. Then, it uses a novel sampling strategy to create a set of training sets. Finally it constructs decision trees based on these training sets and these decision trees can form a random forest (i.e., model). The last phase of DP-Share uses Laplace and exponential mechanisms to satisfy the requirements of DP. In our empirical studies, we choose nine experimental subjects from real software projects. Then, we use AUC (area under ROC curve) as the performance measure and holdout as our model validation technique. After privacy and utility analysis, we find that DP-Share can achieve better performance than a baseline method DF-Enhance in most cases when using the same privacy budget. Moreover, we also provide guidelines to effectively use our proposed method. Our work attempts to fill the research gap in terms of differential privacy for SDP, which can encourage researchers and practitioners to share more SDP models and then effectively advance the state of the art of SDP.展开更多
Deep neural network(DNN)models have been widely used in e-commerce,games,auto-mobiles,manufacturing,and so on.Improper structure,parameters,activation function,or incorrect loss function of the DNN models may cause de...Deep neural network(DNN)models have been widely used in e-commerce,games,auto-mobiles,manufacturing,and so on.Improper structure,parameters,activation function,or incorrect loss function of the DNN models may cause defects in performance or secu-rity.As a result,there are some researches that focus on repairing DNN such as MODE and Apricot.However,the cost of repairing is high or the repair may lead to overfit-ting.In order to solve this problem,we propose GenMuNN,which is a Mutation-Based Approach to Repair Deep Neural Network Models.First,it analyzes the importance of the weights of the neurons in each layer of the DNN model to the correctness of the final prediction results,and ranks the weights according to the influence on the prediction results of the DNN model.Second,mutation is performed to generate mutants based on the rank of weights,and genetic algorithms are used to select mutants for the next round of mutation until the stop condition is touched.Experiments are carried on a set of DNN models which are trained with the MNIST dataset.The experimental results show that GenMuNN can improve the accuracy of the DNN models.展开更多
As the system becomes more intelligent and embedded,the operating environment is gradually changed from closed,static,and controllable to more open,dynamic,and difficult to control.As a result,the design of complex so...As the system becomes more intelligent and embedded,the operating environment is gradually changed from closed,static,and controllable to more open,dynamic,and difficult to control.As a result,the design of complex software systems is faced with many challenges arising from the uncertainty of the environment(UoE).On the one hand,ignoring the UoE to manually describe requirements is not only a tough job,but it can also hinder the discovery of potential requirements;on the other hand,it is a challenge to integrate the representation of and reasoning of UoE into the process of modeling complex systems.Based on the analysis of the characteristics of complex systems engineering,this paper takes solving the UoE caused by stakeholders prefer-ences and complex environment context as the entry point and designs a fuzzy con-trol decision-making framework.Specifically,the framework contributes to the spiral of complex systems while solving the UoE by constructing a closed-loop intelligent sys-tem based on automatic data flow between information space and physical space for environment sensing,uncertainty analysis,requirements mining,fuzzy reasoning,deci-sion execution as well as feedback optimization.Finally,the framework is validated with a concrete example of an adaptive treadmill system based on the support tools developed.展开更多
In the process of complex product design,modeling in different fields and different disciplines is often involved.Designers often face many different development kits,platforms,and theories,among which significant dif...In the process of complex product design,modeling in different fields and different disciplines is often involved.Designers often face many different development kits,platforms,and theories,among which significant differences exist.Especially in the process of algorithm-hardware implementation,it is necessary to have mastery of the knowledge including algorithm,hardware,circuit,and system engineering.In this paper,a modeling method of algorithm-hardware based on SysML is proposed to reduce the difficulty of algorithm-hardware modeling.By using the method,the designers who do not know the knowledge of hardware can also easily build the algorithm-hardware model.In this method,a method of graphical system modeling based on SysML is used,where the elements of the algorithm-hardware model are described by SysML graphical models.Then,the SysML graphical models are converted to Very-High-Speed Integrated Circuit Hardware Description Language.At last,a detecting algorithm of random number is complemented by the modeling method in this paper and the simulation results are presented at the conclusion.展开更多
基金supported by the key scientific and technological projects of Henan Province with Grant No.232102211084the Natural Science Foundation of Henan with Grant No.222300420582+2 种基金the Key Scientific Research Projects of Henan Higher School with Grant No.22A520033Zhengzhou Basic Research and Applied Research Project with Grant No.ZZSZX202107China Logistics Society with Grant No.2022CSLKT3-334.
摘要To serve various tasks requested by various end devices with different requirements,end-edge-cloud(E2C)has attracted more and more attention from specialists in both academia and industry,by combining both benefits of edge and cloud computing.But nowadays,E2C still suffers from low service quality and resource efficiency,due to the geographical distribution of edge resources and the high dynamic of network topology and user mobility.To address these issues,this paper focuses on task offloading,which makes decisions that which resources are allocated to tasks for their processing.This paper first formulates the problem into binary non-linear programming and then proposes a particle swarm optimization(PSO)-based algorithm to solve the problem.The proposed algorithm exploits an imbalance mutation operator and a task rescheduling approach to improve the performance of PSO.The proposed algorithm concerns the resource heterogeneity by correlating the probability that a computing node is decided to process a task with its capacity,by the imbalance mutation.The task rescheduling approach improves the acceptance ratio for a task offloading solution,by reassigning rejected tasks to computing nodes with available resources.Extensive simulated experiments are conducted.And the results show that the proposed offloading algorithm has an 8.93%–37.0%higher acceptance ratio than ten of the classical and up-to-date algorithms,and verify the effectiveness of the imbalanced mutation and the task rescheduling.
基金Supported by the Social Science Foundation of Beijing(15JGB099,15ZHA004)the National Natural Science Foundation of China(61370139)"Information+" Special Fund(5111823610)
摘要In the age of information sharing, logistics information sharing also faces the risk of privacy leakage. In regard to the privacy leakage of time-series location information in the field of logistics, this paper proposes a method based on differential privacy for time-series location data publication. Firstly, it constructs public region of interest(PROI) related to time by using clustering optimal algorithm. And it adopts the method of the centroid point to ensure the public interest point(PIP) representing the location of the public interest zone. Secondly, according to the PIP, we can construct location search tree(LST) that is a commonly used index structure of spatial data, in order to ensure the inherent relation among location data. Thirdly, we add Laplace noise to the node of LST, which means fewer times to add Laplace noise on the original data set and ensures the data availability. Finally, experiments show that this method not only ensures the security of sequential location data publishing, but also has better data availability than the general differential privacy method, which achieves a good balance between the security and availability of data.
基金Supported by the National Natural Science Foundation of China(No.41804135)Key Laboratory of Petroleum Resources Research,Institute of Geology and Geophysics,Chinese Academy of Sciences,Open Project(No.KLOR2018-9)Beijing Information Science and Technology University Research Fund Project(No.2025025).
摘要Seismic geophone is the key instrument for seismic data acquisition in the fields of oil and gas exploration and other relevant fields.It plays an important role in data quality,subsequent processing and interpretation.Aiming at the shortcomings of the existing geophones,such as large volume,heavy weight,unable to monitor in real-time,and heavy workload of data transmission and storage,this paper designs and implements a wireless geophone based on STM32 embedded microcontroller.It is mainly composed of STM32 microcontroller,acceleration sensor,global positioning system(GPS)module,Wi-Fi module and real-time seismic data receiving and processing module.Firstly,the acceleration of vibration in three directions is sensed by the acceleration sensor;secondly,the sampling and analog-to-digital conversion of the vibration data is controlled by the microcontroller;thirdly,the vibration and GPS data are sent to the personal computer(PC)through Wi-Fi,and the personal coomputer PC-side software module completes the reception,display,monitoring and storage of the seismic data;finally,the feasibility and effectiveness of the designed wireless geophone are verified through actual seismic data acquisition experiments.
基金the National Natural Science Foundation of China(No.41804135)the Key Laboratory of Petroleum Resources Research,Institute of Geology and Geophysics,Chinese Academy of Sciences,Open Project(No.KLOR2018-9)the Beijing Information Science and Technology University Research Fund Project(No.2025025).
摘要Aiming at the problems of low accuracy,long time consumption,and failure to obtain quantita-tive fault identification results of existing automatic fault identification technic,a fault recognition method based on clustering linear regression is proposed.Firstly,Hough transform is used to detect the line segment of the enhanced image obtained by the coherence cube algorithm.Secondly,the endpoint of the line segment detected by Hough transform is taken as the key point,and the adaptive clustering linear regression algorithm is used to cluster the key points adaptively according to the lin-ear relationship between them.Finally,a fault is generated from each category of key points based on least squares curve fitting method to realize fault identification.To verify the feasibility and pro-gressiveness of the proposed method,it is compared with the traditional method and the latest meth-od on the actual seismic data through experiments,and the effectiveness of the proposed method is verified by the experimental results on the actual seismic data.
基金This research is supported by The National Natural Science Foundation of China under Grant(No.61672101)Beijing Key Laboratory of Internet Culture and Digital Dissemination Research(No.ICDDXN004)Key Lab of Information Network Security of Ministry of Public Security(No.C18601).
摘要In order to quickly and accurately find the implementer of the network crime,based on the user portrait technology,a rapid detection method for users with abnormal behaviors is proposed.This method needs to construct the abnormal behavior rule base on various kinds of abnormal behaviors in advance,and construct the user portrait including basic attribute tags,behavior attribute tags and abnormal behavior similarity tags for network users who have abnormal behaviors.When a network crime occurs,firstly get the corresponding tag values in all user portraits according to the category of the network crime.Then,use the Naive Bayesian method matching each user portrait,to quickly locate the most likely network criminal suspects.In the case that no suspect is found,all users are audited comprehensively through matching abnormal behavior rule base.The experimental results show that,the accuracy rate of using this method for fast detection of network crimes is 95.9%,and the audit time is shortened to 1/35 of that of the conventional behavior audit method.
基金supported in part by the Key Project of Beijing Higher Education Association in 2023(No.ZD2023111)Beijing Information Science and Technology University Teaching Reform Project(No.2024JGYB23).
摘要Within the context of Massive Open Online Courses(MOoCs),the application of Human-in-the-loop systems is becoming increasingly prevalent.Given the issue of high dropout rates in MOoCs,developing accurate dropout prediction models is essential to improve educational outcomes and ensure the sustainability of the platform.Researchers usually use interactive information between students and platforms to build predictive models.However,existing methods have the problem that the single construction of behavioral characteristics leads to misclassification of special student groups.Therefore,after in-depth analysis of the behavioral data of MOOC learners,this paper constructs the characteristics of learning activity based on the two dimensions of learning time and number of clicks to reduce the misclassification of special groups.On this basis,we propose a hybrid neural network model(CNN-LSTMAE)to model and predict dropout behavior.CNNLSTMAE uses the Convolutional Neural Network(CNN)to extract local features of students'behaviors,and uses the Long-Short-Term Memory Autoencoder(LSTMAE)module to perform a high-level abstract representation of local features.Experimental results on the KDD Cup 2015 dataset show that the proposed model has better predictive performance than the baseline methods.
基金supported by the Leading-Edge Technology Program of Jiangsu Natural Science Foundation of China under Grant No.BK20202001the National Natural Science Foundation of China under Grant No.61702041the Beijing Information Science and Technology University“Qin-Xin Talent”Cultivation Project under Grant No.QXTCP C201906.
摘要With the widespread use of agile software development methods,such as agile and scrum,software is iteratively updated more frequently.To ensure the quality of the software,regression testing is conducted before new versions are released.Moreover,to improve the efficiency of regression testing,testing efforts should be concentrated on the modified and impacted parts of a program.However,the costs of manually constructing new test cases for the modified and impacted parts are relatively expensive.Fuzz testing is an effective method for generating test data automatically,but it is usually devoted to achieving higher code coverage,which makes fuzz testing unsuitable for direct regression testing scenarios.For this reason,we propose a fuzz testing method based on the guidance of historical version information.First,the differences between the program being tested and the last version are analyzed,and the results of the analysis are used to locate change points.Second,change impact analysis is performed to find the corresponding impacted basic blocks.Finally,the fitness values of test cases are calculated according to the execution traces,and new test cases are generated iteratively by the genetic algorithm.Based on the proposed method,we implement a prototype tool DeltaFuzz and conduct experiments on six open-source projects.Compared with the fuzzing tool AFLGo,AFLFast and AFL,DeltaFuzz can reach the target faster,and the time taken by DeltaFuzz was reduced by 20.59%,30.05%and 32.61%,respectively.
基金Supported by Seminar of National Social Funds Project(12&ZD234)
摘要Ancient Chinese characters, typically the ideographic characters on bones and bronze before Shang Dynasty(16th—11th century B.C.), are valuable culture legacy of history. However the recognition of Ancient Chinese characters has been the task of paleography experts for long. With the help of modern computer technique, everyone can expect to be able to recognize the characters and understand the ancient inscriptions. This research is aimed to help people recognize and understand those ancient Chinese characters by combining Chinese paleography theory and computer information processing technology. Based on the analysis of ancient character features, a method for structural character recognition is proposed. The important characteristics of strokes and basic components or radicals used in recognition are introduced in detail. A system was implemented based on above method to show the effectiveness of the method.
基金supported by the Promoting the Classification and Development of Colleges-Student Innovation and Entrepreneurship Training Program(School of Computer)under Grant No.5112410852.
摘要Protecting healthcare data privacy and security is crucial in advanced manufacturing,which involves medical devices.It encompasses patient records and clinical trial data.Federated learning emerges as a solution that enables model training across different institutions without compromising data privacy and security.However,existing frameworks often exhibit a bias towards clients with larger data volumes,neglecting the connection between global and local model performance.This can result in suboptimal aggregation of the global model,thereby affecting the effectiveness and efficiency of the overall process.To address these limitations,we propose a performance evaluation-driven federated learning framework(PedFed).The primary objective of PedFed is to enhance global model aggregation and improve communication efficiency.Our approach involves a client selection strategy based on performance evaluation of local and global models.Specifically,we introduce the concept of local model improvement(LMI)using Intersection over Union(IoU)for client selection in medical image segmentation scenarios.Moreover,we introduce a dynamic aggregation framework incorporating validation IoU as a weighting factor to mitigate model divergence caused by not independent and identically distributed(non-IID)data.We focus on performing image segmentation tasks to simulate the analysis of sensitive data in the healthcare domain.Experimental results conducted on brain tumor and heart segmentation datasets demonstrate the superiority of the PedFed framework over the baseline framework,confirming its benefits in communication efficiency.
基金This work was partly supported by the National Natural Science Foundation of China(Nos.61902029 and 61872044)R&D Program of Beijing Municipal Education Commission(No.KM202011232015).
摘要Mobile edge computing(MEC),as a new distributed computing model,satisfies the low energy consumption and low latency requirements of computation-intensive services.The task offloading of MEC has become an important research hotspot,as it solves the problems of insufficient computing capability and battery capacity of Internet of things(IoT)devices.This study investigates task offloading scheduling in a dynamic MEC system.By integrating energy harvesting technology into IoT devices,we propose a hybrid energy supply model.We jointly optimize local computing,offloading duration,and edge computing decisions to minimize system cost.On the basis of stochastic optimization theory,we design an online dynamic task offloading algorithm for MEC with a hybrid energy supply called DTOME.DTOME can make task offloading decisions by weighing system cost and queue stability.We quote dynamic programming theory to obtain the optimal task offloading strategy.Simulation results verify the effectiveness of DTOME,and show that DTOME entails lower system cost than two baseline task offloading strategies.
基金supported by the National Key Basic Research and Development (973) Program of China(No. 2010CB328105)the National Natural Science Foundation of China (Nos. 61020106002,61071065,and 11171368)+2 种基金China Postdoctoral Science Foundation (No. 2013M540952)Tsinghua University Initiative Scientific Research Program (No. 20121087999)SGCC research and development projects
摘要The technology of Ultra-High Voltage (UHV) transmission requires higher dependability for electric power grid. Power Grid Communication Networking (PGCN), the fundamental information infrastructure, severs data transmission including control signal, protection signal, and common data services. Dependability is the necessary requirement to ensure services timely and accurately. Dependability analysis aims to predicate operation status and provide suitable strategies getting rid of the potential dangers. Due to the dependability of PGCN may be affected by external environment, devices quality, implementation strategies, and so on, the scale explosion and the structure complexity make the PGCN's dependability much challenging. In this paper, with the observation of interdependency between power grid and PGCN, we propose an electricity services based dependability analysis model of PGCN. The model includes methods of analyzing its dependability and procedures of designing the dependable strategies. We respectively discuss the deterministic analysis method based on matrix analysis and stochastic analysis model based on stochastic Petri nets.
基金partially supported by the National Natural Science Foundation of China under Grant Nos. 61702041 and 61872263the Open Project of State Key Laboratory for Novel Software Technology at Nanjing University under Grant No. KFKT2019B14+2 种基金the Science and Technology Project of Beijing Municipal Education Commission under Grant No. KM201811232016the Nantong Application Research Plan under Grant No. JC2018134Jiangsu Government Scholarship for Overseas Studies.
摘要In current software defect prediction (SDP) research, most previous empirical studies only use datasets provided by PROMISE repository and this may cause a threat to the external validity of previous empirical results. Instead of SDP dataset sharing, SDP model sharing is a potential solution to alleviate this problem and can encourage researchers in the research community and practitioners in the industrial community to share more models. However, directly sharing models may result in privacy disclosure, such as model inversion attack. To the best of our knowledge, we are the first to apply differential privacy (DP) to privacy-preserving SDP model sharing and then propose a novel method DP-Share, since DP mechanisms can prevent this attack when the privacy budget is carefully selected. In particular, DP-Share first performs data preprocessing for the dataset, such as over-sampling for minority instances (i.e., defective modules) and conducting discretization for continuous features to optimize privacy budget allocation. Then, it uses a novel sampling strategy to create a set of training sets. Finally it constructs decision trees based on these training sets and these decision trees can form a random forest (i.e., model). The last phase of DP-Share uses Laplace and exponential mechanisms to satisfy the requirements of DP. In our empirical studies, we choose nine experimental subjects from real software projects. Then, we use AUC (area under ROC curve) as the performance measure and holdout as our model validation technique. After privacy and utility analysis, we find that DP-Share can achieve better performance than a baseline method DF-Enhance in most cases when using the same privacy budget. Moreover, we also provide guidelines to effectively use our proposed method. Our work attempts to fill the research gap in terms of differential privacy for SDP, which can encourage researchers and practitioners to share more SDP models and then effectively advance the state of the art of SDP.
基金This work was supported by the Beijing Information Science and Technology Uni-versity“Qin-Xin Talent”Cultivation Project(No.QXTCP C201906)the Bei-jing Information Science and Technology University Research Level Improvement Project(No.2020KYNH214)the Science and Technology Project of the Bei-jing Municipal Education Commission(No.KM201811232016)。
摘要Deep neural network(DNN)models have been widely used in e-commerce,games,auto-mobiles,manufacturing,and so on.Improper structure,parameters,activation function,or incorrect loss function of the DNN models may cause defects in performance or secu-rity.As a result,there are some researches that focus on repairing DNN such as MODE and Apricot.However,the cost of repairing is high or the repair may lead to overfit-ting.In order to solve this problem,we propose GenMuNN,which is a Mutation-Based Approach to Repair Deep Neural Network Models.First,it analyzes the importance of the weights of the neurons in each layer of the DNN model to the correctness of the final prediction results,and ranks the weights according to the influence on the prediction results of the DNN model.Second,mutation is performed to generate mutants based on the rank of weights,and genetic algorithms are used to select mutants for the next round of mutation until the stop condition is touched.Experiments are carried on a set of DNN models which are trained with the MNIST dataset.The experimental results show that GenMuNN can improve the accuracy of the DNN models.
摘要As the system becomes more intelligent and embedded,the operating environment is gradually changed from closed,static,and controllable to more open,dynamic,and difficult to control.As a result,the design of complex software systems is faced with many challenges arising from the uncertainty of the environment(UoE).On the one hand,ignoring the UoE to manually describe requirements is not only a tough job,but it can also hinder the discovery of potential requirements;on the other hand,it is a challenge to integrate the representation of and reasoning of UoE into the process of modeling complex systems.Based on the analysis of the characteristics of complex systems engineering,this paper takes solving the UoE caused by stakeholders prefer-ences and complex environment context as the entry point and designs a fuzzy con-trol decision-making framework.Specifically,the framework contributes to the spiral of complex systems while solving the UoE by constructing a closed-loop intelligent sys-tem based on automatic data flow between information space and physical space for environment sensing,uncertainty analysis,requirements mining,fuzzy reasoning,deci-sion execution as well as feedback optimization.Finally,the framework is validated with a concrete example of an adaptive treadmill system based on the support tools developed.
基金This work is supported by the National Key R&D Program of China(Grant No.2018YFB1701602).
摘要In the process of complex product design,modeling in different fields and different disciplines is often involved.Designers often face many different development kits,platforms,and theories,among which significant differences exist.Especially in the process of algorithm-hardware implementation,it is necessary to have mastery of the knowledge including algorithm,hardware,circuit,and system engineering.In this paper,a modeling method of algorithm-hardware based on SysML is proposed to reduce the difficulty of algorithm-hardware modeling.By using the method,the designers who do not know the knowledge of hardware can also easily build the algorithm-hardware model.In this method,a method of graphical system modeling based on SysML is used,where the elements of the algorithm-hardware model are described by SysML graphical models.Then,the SysML graphical models are converted to Very-High-Speed Integrated Circuit Hardware Description Language.At last,a detecting algorithm of random number is complemented by the modeling method in this paper and the simulation results are presented at the conclusion.