Based on the theory of elastic mechanics and material mechanics, the orientation precision of the hohl schaft kegel（HSK） tooling system in static and dynamic states is theoretically and experimentally studied. The r...Based on the theory of elastic mechanics and material mechanics, the orientation precision of the hohl schaft kegel（HSK） tooling system in static and dynamic states is theoretically and experimentally studied. The relation between the clamping force and the shank taper is obtained. And a proper clamping force is found to be essential to assure the axial and radial orientation precisions of the HSK tooling system in high speed machining （HSM）. Analytical results show that the reason why the HSK tooling system can keep high precision at the high rotational speed is that the actual axial clamping force keeps the two surfaces of the shank and the spindle in contact all the time.展开更多
According to the structure of the hohl schaft kegel（HSK） tooling system and its working principle, a mechanical model of the HSK tooling system is established. Major factors influencing the stiffness of the system a...According to the structure of the hohl schaft kegel（HSK） tooling system and its working principle, a mechanical model of the HSK tooling system is established. Major factors influencing the stiffness of the system are analyzed and the relationship between the load and the manufacturing quality is obtained. The basic rule of the stiffness variation is presented and the theoretical analysis is in a good agreement with experimental results. The dynamic stiffness must also be considered to evaluate the performance of the tooling system besides the staticstiffness. Finally, the selecting principles of the HSK types are proposed and their optimum operating conditions are established.展开更多
Anxiety,motivation,and strategy have long been seen as critical in second language acquisition.This study presents a systematic review of the literature on these variables in terms of their relationship with one anoth...Anxiety,motivation,and strategy have long been seen as critical in second language acquisition.This study presents a systematic review of the literature on these variables in terms of their relationship with one another,their effects on learning outcomes,and how they are affected by technology-assisted tools in the teaching of Chinese as a second language.This study includes 24 articles for the review study based on the criteria and process of the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocol(PRISMA-P)and the clustering techniques of VOSviewer.It is found that 1)anxiety,motivation,and strategy were interrelated,that is,motivation was negatively associated with anxiety but positively related to strategy,while strategy could positively predict anxiety;2)anxiety could both positively and negatively affect learning outcomes,while motivation and strategy could both positively and insignificantly influence learning outcomes;3)the technology-assisted tools used in the classroom could both positively and negatively affect the levels of these variables and learning outcomes in the L2 Chinese context.The need to explore more complicated relationships between language-specific individual variables themselves and other possible factors that affect these variables,such as cultural ones,are also discussed for future research.展开更多
Objective:This study aimed to systematically evaluate the measurement characteristics and methodological quality of childbirth experience assessment tools,with a view to informing the selection of healthcare professio...Objective:This study aimed to systematically evaluate the measurement characteristics and methodological quality of childbirth experience assessment tools,with a view to informing the selection of healthcare professionals who can provide high-quality assessment tools.Method:A systematic search was performed on specific databases:PubMed,Web of Science,Embase,CINAHL,SinoMed,China National Knowledge Infrastructure(CNKI),and Wanfang,from inception to February 29,2024.The researchers retrieved studies on the measurement attributes of the childbirth experience assessment tool,and traced back the references of the included studies to supplement relevant literature.According to the inclusion and exclusion criteria,screening and data extraction were independently undertaken by two reviewers.Two researchers individually used the Consensus-based Standards for the Selection of Health Measurement Instruments(COSMIN)Risk of Bias Checklist to assess the methodological quality of the scale,applied the COSMIN criteria to evaluate the measurement properties of the scale,and used a modified Grading of Recommendations,Assessment,Development,and Evaluation(GRADE)system to assess the certainty of evidence.Result:A total of 15 studies were included to evaluate the psychometric properties of 11 childbirth experience assessment tools(including different language versions).Eight studies’methodological quality of content validity was doubtful,and the remaining studies did not report content validity.None of the tools reported measurement error,cross-cultural validity,or responsiveness.In light of the questionable or unreported content validity of the tools,the evidence quality was deemed moderate or below.Consequently,the 11 assessment tools were recommended as grade B.Conclusion:In contrast,the Questionnaire for Assessing the Childbirth Experience(QACE)is recommended for provisional use,given its relatively good methodological and measurement attributes and appropriate content for evaluation.However,further validation of other measurement properties is needed.展开更多
This paper presents a high-security medical image encryption method that leverages a novel and robust sine-cosine map.The map demonstrates remarkable chaotic dynamics over a wide range of parameters.We employ nonlinea...This paper presents a high-security medical image encryption method that leverages a novel and robust sine-cosine map.The map demonstrates remarkable chaotic dynamics over a wide range of parameters.We employ nonlinear analytical tools to thoroughly investigate the dynamics of the chaotic map,which allows us to select optimal parameter configurations for the encryption process.Our findings indicate that the proposed sine-cosine map is capable of generating a rich variety of chaotic attractors,an essential characteristic for effective encryption.The encryption technique is based on bit-plane decomposition,wherein a plain image is divided into distinct bit planes.These planes are organized into two matrices:one containing the most significant bit planes and the other housing the least significant ones.The subsequent phases of chaotic confusion and diffusion utilize these matrices to enhance security.An auxiliary matrix is then generated,comprising the combined bit planes that yield the final encrypted image.Experimental results demonstrate that our proposed technique achieves a commendable level of security for safeguarding sensitive patient information in medical images.As a result,image quality is evaluated using the Structural Similarity Index(SSIM),yielding values close to zero for encrypted images and approaching one for decrypted images.Additionally,the entropy values of the encrypted images are near 8,with a Number of Pixel Change Rate(NPCR)and Unified Average Change Intensity(UACI)exceeding 99.50%and 33%,respectively.Furthermore,quantitative assessments of occlusion attacks,along with comparisons to leading algorithms,validate the integrity and efficacy of our medical image encryption approach.展开更多
BACKGROUND Brain-computer interface(BCI)technology is rapidly advancing in psychiatry.Informed consent competency(ICC)assessment among psychiatric patients is a pivotal concern in clinical research.AIM To analyze the ...BACKGROUND Brain-computer interface(BCI)technology is rapidly advancing in psychiatry.Informed consent competency(ICC)assessment among psychiatric patients is a pivotal concern in clinical research.AIM To analyze the assessment of ICC and form a framework with multi-dimensional elements involved in ICC of BCI clinical research among psychiatric disorders.METHODS A systematic review of studies regarding ICC assessments of BCI clinical research in patients with six kinds of psychiatric disorders was conducted.A systematic literature search was performed using PubMed,ScienceDirect,and Web of Science.Peer-reviewed articles and full-text studies were included in the analysis.There were no date restrictions,and all studies published up to February 27,2025,were included.RESULTS A total of 103 studies were selected for this review.Fifty-eight studies included ICC factors,and forty-five were classified in ICC related ethical issues of BCI research in six kinds of psychiatric disorders.Executive function impairment is widely recognized as the most significant factor impacting ICC,and processing speed deficits are observed in schizophrenia,mood disorders,and Alzheimer’s disease.Memory dysfunction,particularly episodic and working memory,contributes to compromised ICC.Five core ethical issues in BCI research should be addressed:BCI specificity,vulnerability,autonomy,dynamic ICC,comprehensiveness,and uncertainty.CONCLUSION A Five-Dimensional evaluative framework,including clinical,ethical,sociocultural,legal,and procedural dimensions,is constructed and proposed for future ICC research in BCI clinical research involving psychiatric disorders.展开更多
With the shift in the definition of disease from non-alcoholic fatty liver disease(NAFLD)to metabolism-associated fatty liver disease(MAFLD),as well as the rapid evolution of pathological classification and therapeuti...With the shift in the definition of disease from non-alcoholic fatty liver disease(NAFLD)to metabolism-associated fatty liver disease(MAFLD),as well as the rapid evolution of pathological classification and therapeutic targets,traditional clinical teaching models face challenges such as outdated guideline updates,disjointed translation of scientific research,and limited skill training.This study proposes a dynamic training model integrating“guidelines,clinical practice,and scientific research.”Through stratified case-based teaching(e.g.,FibroScan simulator and metabolic sand table),dynamic guideline analysis(comparing old and new evidence),and the integration of scientific thinking(visualization of CAND1 protein mechanism),a teaching system that integrates theory and practice is constructed.Innovatively developed smart assistant tools(AI decision support system,VR liver biopsy simulator)and a multi-dimensional evaluation system(deviation analysis of diagnosis and treatment pathways,milestone assessment)are used while emphasizing metabolic medicine integration(continuous glucose monitoring and digital therapy)and ethical privacy protection(federated learning framework).This model aims to cultivate students’evidence-based decision-making skills and scientific research transformation thinking through dynamic knowledge base construction and interdisciplinary collaboration,providing sustainable teaching solutions to cope with the rapid iteration of NAFLD diagnosis and treatment.展开更多
The principle and the constitution of an intelligent system for on-line and real-time montitoring tool cutting state were discussed and a synthetic sensors schedule combined a new type fluid acoustic emission sens...The principle and the constitution of an intelligent system for on-line and real-time montitoring tool cutting state were discussed and a synthetic sensors schedule combined a new type fluid acoustic emission sensor (AE) with motor current sensor was presented. The parallel communication between control system of machine tools, the monitoring intelligent system,and several decision-making systems for identifying tool cutting state was established It can auto - matically select the sensor way ,monitoring mode and identifying method in machining process- ing so as to build a successful and effective intelligent system for on -line and real-time moni- toring cutting tool states in FMS.展开更多
The necessity and feasibility of an expert system for carbide-tool utilization are analyzed and a practical system named CUES(carbide-tool utilization expert system ) is developed and realized. The system concept, mod...The necessity and feasibility of an expert system for carbide-tool utilization are analyzed and a practical system named CUES(carbide-tool utilization expert system ) is developed and realized. The system concept, module structure, data management, inference strategy and the interface design of the system are discussed in.detail. The system would be useful not only for the preparation of tool bank of FMS or CIMS, but the for the proper application of cemented carbide tools in conventional machining Processes.展开更多
Reliable on line cutting tool conditioning monitoring is an essential feature of automatic machine tool and flexible manufacturing system (FMS) and computer integrated manufacturing system (CIMS). Recently artificia...Reliable on line cutting tool conditioning monitoring is an essential feature of automatic machine tool and flexible manufacturing system (FMS) and computer integrated manufacturing system (CIMS). Recently artificial neural networks (ANNs) are used for this purpose in conjunction with suitable sensory systems. The present work in Norwegian University of Science and Technology (NTNU) uses back propagation neural networks (BP) and fuzzy neural networks (FNN) to process the cutting tool state data measured with force and acoustic emission (AE) sensors, and implements a valuable on line tool condition monitoring system using the ANNs. Different ANN structures are designed and investigated to estimate the tool wear state based on the fusion of acoustic emission and force signals. Finally, four case studies are introduced for the sensing and ANN processing of the tool wear states and the failures of the tool with practical experiment examples. The results indicate that a tool wear identification system can be achieved using the sensors integration with ANNs, and that ANNs provide a very effective method of implementing sensor integration for on line monitoring of tool wear states and abnormalities.展开更多
This paper describes a technology of dynamic display moving image by computer monitor,which is initially used in the design of tool detection system. The paper presents the hardware and software principie and edge det...This paper describes a technology of dynamic display moving image by computer monitor,which is initially used in the design of tool detection system. The paper presents the hardware and software principie and edge detection process. The way of marking edge point coordinates and stability of moving image also is analyzed. The method reforms the conventional design of the 2-D vision detection system. Moreover,it facilitates the design of the systematic mechanical construction,is convenient to compile instrument systemsoftware,and realizes to detect and track display image simultaneously. By the work,the tool detection system is improved to practical application.展开更多
Parallel kinematics machine （PKM） is advantageous over the serial machine tools in processing the complex-surface products. A manufacturing service system for PKM is developed to provide the services of the complex-...Parallel kinematics machine （PKM） is advantageous over the serial machine tools in processing the complex-surface products. A manufacturing service system for PKM is developed to provide the services of the complex-surface machining for potential geographically-dispersed manufacturing enterprises. In order to easily in- tegrate the external system, Web services are used to encapsulate post-processing functions of PKM legacy sys- tems, including compilation, workspace calculation, interfere calibration, and kinematics transformation. A ser- vice-oriented architecture（SOA） is proposed for the cooperative work between the PKM system and its client. The workflow and the function module of this manufacturing service system are presented. An example shows that as a result of SOA and loose coupling, such a Web service-based manufacturing service system is easier to in- tegrate and interoperate with its client. Meanwhile, the system decreases the manufacturing cost and improves the efficiency than its former kind of distributed system.展开更多
Objective expertise evaluation of individuals,as a prerequisite stage for team formation,has been a long-term desideratum in large software development companies.With the rapid advancements in machine learning methods...Objective expertise evaluation of individuals,as a prerequisite stage for team formation,has been a long-term desideratum in large software development companies.With the rapid advancements in machine learning methods,based on reliable existing data stored in project management tools’datasets,automating this evaluation process becomes a natural step forward.In this context,our approach focuses on quantifying software developer expertise by using metadata from the task-tracking systems.For this,we mathematically formalize two categories of expertise:technology-specific expertise,which denotes the skills required for a particular technology,and general expertise,which encapsulates overall knowledge in the software industry.Afterward,we automatically classify the zones of expertise associated with each task a developer has worked on using Bidirectional Encoder Representations from Transformers(BERT)-like transformers to handle the unique characteristics of project tool datasets effectively.Finally,our method evaluates the proficiency of each software specialist across already completed projects from both technology-specific and general perspectives.The method was experimentally validated,yielding promising results.展开更多
Modern manufacturing processes have become more reliant on automation because of the accelerated transition from Industry 3.0 to Industry 4.0.Manual inspection of products on assembly lines remains inefficient,prone t...Modern manufacturing processes have become more reliant on automation because of the accelerated transition from Industry 3.0 to Industry 4.0.Manual inspection of products on assembly lines remains inefficient,prone to errors and lacks consistency,emphasizing the need for a reliable and automated inspection system.Leveraging both object detection and image segmentation approaches,this research proposes a vision-based solution for the detection of various kinds of tools in the toolkit using deep learning(DL)models.Two Intel RealSense D455f depth cameras were arranged in a top down configuration to capture both RGB and depth images of the toolkits.After applying multiple constraints and enhancing them through preprocessing and augmentation,a dataset consisting of 3300 annotated RGB-D photos was generated.Several DL models were selected through a comprehensive assessment of mean Average Precision(mAP),precision-recall equilibrium,inference latency(target≥30 FPS),and computational burden,resulting in a preference for YOLO and Region-based Convolutional Neural Networks(R-CNN)variants over ViT-based models due to the latter’s increased latency and resource requirements.YOLOV5,YOLOV8,YOLOV11,Faster R-CNN,and Mask R-CNN were trained on the annotated dataset and evaluated using key performance metrics(Recall,Accuracy,F1-score,and Precision).YOLOV11 demonstrated balanced excellence with 93.0%precision,89.9%recall,and a 90.6%F1-score in object detection,as well as 96.9%precision,95.3%recall,and a 96.5%F1-score in instance segmentation with an average inference time of 25 ms per frame(≈40 FPS),demonstrating real-time performance.Leveraging these results,a YOLOV11-based windows application was successfully deployed in a real-time assembly line environment,where it accurately processed live video streams to detect and segment tools within toolkits,demonstrating its practical effectiveness in industrial automation.The application is capable of precisely measuring socket dimensions by utilising edge detection techniques on YOLOv11 segmentation masks,in addition to detection and segmentation.This makes it possible to do specification-level quality control right on the assembly line,which improves the ability to examine things in real time.The implementation is a big step forward for intelligent manufacturing in the Industry 4.0 paradigm.It provides a scalable,efficient,and accurate way to do automated inspection and dimensional verification activities.展开更多
Thermal fatigue and high temperature wear are the two principle failure mechanisms for thixoforming dies. Samples of Inconel 617 and Stellite 6 alloys were submitted to thermal cycling under conditions which approxima...Thermal fatigue and high temperature wear are the two principle failure mechanisms for thixoforming dies. Samples of Inconel 617 and Stellite 6 alloys were submitted to thermal cycling under conditions which approximate thixoforming of steels and to sliding wear tests at 750 ℃. The experimental results thus obtained were compared with those of the X32CrMoV33 hot work tool steel. The Inconel 617 and Stellite 6 samples are much more resistant to oxidation and to softening than the hot work tool steel, providing a superior resistance to thermal fatigue cracking. The wear resistance of the Inconel 617 and Stellite 6 alloys at 750 ℃ is also markedly superior. The adhesive oxides growing slowly on Inconel 617 and Stellite 6 alloys sustain the wear action without spalling and are claimed to be responsible for the superior wear resistance of these alloys at 750 ℃.展开更多
A systematic geometric model has been presented for calibration of a newly designed 5-axis turbine blade grinding machine. This machine is designed to serve a specific purpose to attain high accuracy and high efficien...A systematic geometric model has been presented for calibration of a newly designed 5-axis turbine blade grinding machine. This machine is designed to serve a specific purpose to attain high accuracy and high efficiency grinding of turbine blades by eliminating the hand grinding process. Although its topology is RPPPR （P： prismatic; R： rotary）, its design is quite distinct from the competitive machine tools. As error quantification is the only way to investigate, maintain and improve its accuracy, calibra- tion is recommended for its performance assessment and acceptance testing. Systematic geometric error modeling technique is implemented and 52 position dependent and position independent errors are identified while considering the machine as five rigid bodies by eliminating the set-up errors of workpiece and cutting tool. 39 of them are found to have influential errors and are accommodated for finding the resultant effect between the cutting tool and the workpiece in workspace volume. Rigid body kinematics techniques and homogenous transformation matrices are used for error synthesis.展开更多
The present work compares microstructures of hot work steels made by different processes, that is, by sprayforming,by casting, and a commercially supplied H13 steel. Material benefits are recognized by sprayforming ho...The present work compares microstructures of hot work steels made by different processes, that is, by sprayforming,by casting, and a commercially supplied H13 steel. Material benefits are recognized by sprayforming hot working tools such as die inserts for hot forging. The sprayformed hot work steels present a fine and homogeneous microstructure,which implies that, at a similar toughness level, the sprayformed steel can be higher alloyed, so that the thermal fatigue and wear resistance at elevated temperatures can be improved. A series of steels with higher vanadium content than commercial hot work steels are developed. There are no segregation and carbide network problems usually encountered in conventional ingot/forging processed high-vanadium steels. Microstructure and hardness of the new sprayformed steels are studied under different heat treatment conditions. It is justified that these sprayformed steels can be directly used for tooling without high temperature hardening. Sprayforming the tool steels onto a precision ceramic mould is demonstrated to extend the technoeconomical benefits, so that a net shape production tool can be rapidly made.Features of the rapid tooling process are also discussed.展开更多
As a key te..hnology in the field of advanced manufacturing, an open architecture controller is studied. In order to develop an open architecture software-CNC system on personal computer （PC） according to open modul...As a key te..hnology in the field of advanced manufacturing, an open architecture controller is studied. In order to develop an open architecture software-CNC system on personal computer （PC） according to open modular architecture controllers （OMAC）. First, the software and hardware platform is chosen and software realization methodology for the CNC system is determined. Second, static modeling methods of an open architecture controller inclusive of object-oriented （OO） programming technology, dynamic link library （DLL） technology and system modules partition are investigated. Third, the dynamical behavioral modeling and the data flow representation of open architecture controller are discussed, which are both described in hierarchy fmite state machine （FSM） model. Fourth, a reusable software module model is established to develop software function module library. Finally, a 3-axis milling machine tool test-bed, named for HIT-CNC, is successfully designed by means of the constructed software function module library and the system configuring method. The experimental results show that, besides increasing the degree of reusability and openness, application of above-mentioned method- ology leads to significant decrease of development time as well as maintenance cost.展开更多
Off-line programming （OLP） system becomes one of the most important programming modules for the robotic belt grinding process, however there lacks research on increasing the grinding dexterous space depending on the...Off-line programming （OLP） system becomes one of the most important programming modules for the robotic belt grinding process, however there lacks research on increasing the grinding dexterous space depending on the OLP system. A new type of grinding robot and a novel robotic belt grinding workcell are forwarded, and their features are briefly introduced. An open and object-oriented off-line programming system is developed for this robotic belt grinding system. The parameters of the trimmed surface are read from the initial graphics exchange specification （IGES） file of the CAD model of the workpiece. The deBoor-Cox basis function is used to sample the grinding target with local contact frame on the workpiece. The numerical formula of inverse kinematics is set up based on Newton＇s iterative procedure, to calculate the grinding robot configurations corresponding to the grinding targets. After the grinding path is obtained, the OLP system turns to be more effective than the teach-by-showing system. In order to improve the grinding workspace, an optimization algorithm for dynamic tool frame is proposed and performed on the special robotic belt grinding system. The initial tool frame and the interval of neighboring tool frames are defined as the preparation of the algorithm. An optimized tool local frame can be selected to grind the complex surface for a maximum dexterity index of the robot. Under the optimization algorithm, a simulation of grinding a vane is included and comparison of grinding workspace is done before and after the tool frame optimization. By the algorithm, the grinding workspace can be enlarged. Moreover the dynamic tool frame can be considered to add one degree-of-freedom to the grinding kinematical chain, which provides the theoretical support for the improvement of robotic dexterity for the complex surface grinding.展开更多
文摘Based on the theory of elastic mechanics and material mechanics, the orientation precision of the hohl schaft kegel（HSK） tooling system in static and dynamic states is theoretically and experimentally studied. The relation between the clamping force and the shank taper is obtained. And a proper clamping force is found to be essential to assure the axial and radial orientation precisions of the HSK tooling system in high speed machining （HSM）. Analytical results show that the reason why the HSK tooling system can keep high precision at the high rotational speed is that the actual axial clamping force keeps the two surfaces of the shank and the spindle in contact all the time.
文摘According to the structure of the hohl schaft kegel（HSK） tooling system and its working principle, a mechanical model of the HSK tooling system is established. Major factors influencing the stiffness of the system are analyzed and the relationship between the load and the manufacturing quality is obtained. The basic rule of the stiffness variation is presented and the theoretical analysis is in a good agreement with experimental results. The dynamic stiffness must also be considered to evaluate the performance of the tooling system besides the staticstiffness. Finally, the selecting principles of the HSK types are proposed and their optimum operating conditions are established.
文摘Anxiety,motivation,and strategy have long been seen as critical in second language acquisition.This study presents a systematic review of the literature on these variables in terms of their relationship with one another,their effects on learning outcomes,and how they are affected by technology-assisted tools in the teaching of Chinese as a second language.This study includes 24 articles for the review study based on the criteria and process of the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocol(PRISMA-P)and the clustering techniques of VOSviewer.It is found that 1)anxiety,motivation,and strategy were interrelated,that is,motivation was negatively associated with anxiety but positively related to strategy,while strategy could positively predict anxiety;2)anxiety could both positively and negatively affect learning outcomes,while motivation and strategy could both positively and insignificantly influence learning outcomes;3)the technology-assisted tools used in the classroom could both positively and negatively affect the levels of these variables and learning outcomes in the L2 Chinese context.The need to explore more complicated relationships between language-specific individual variables themselves and other possible factors that affect these variables,such as cultural ones,are also discussed for future research.
文摘Objective:This study aimed to systematically evaluate the measurement characteristics and methodological quality of childbirth experience assessment tools,with a view to informing the selection of healthcare professionals who can provide high-quality assessment tools.Method:A systematic search was performed on specific databases:PubMed,Web of Science,Embase,CINAHL,SinoMed,China National Knowledge Infrastructure(CNKI),and Wanfang,from inception to February 29,2024.The researchers retrieved studies on the measurement attributes of the childbirth experience assessment tool,and traced back the references of the included studies to supplement relevant literature.According to the inclusion and exclusion criteria,screening and data extraction were independently undertaken by two reviewers.Two researchers individually used the Consensus-based Standards for the Selection of Health Measurement Instruments(COSMIN)Risk of Bias Checklist to assess the methodological quality of the scale,applied the COSMIN criteria to evaluate the measurement properties of the scale,and used a modified Grading of Recommendations,Assessment,Development,and Evaluation(GRADE)system to assess the certainty of evidence.Result:A total of 15 studies were included to evaluate the psychometric properties of 11 childbirth experience assessment tools(including different language versions).Eight studies’methodological quality of content validity was doubtful,and the remaining studies did not report content validity.None of the tools reported measurement error,cross-cultural validity,or responsiveness.In light of the questionable or unreported content validity of the tools,the evidence quality was deemed moderate or below.Consequently,the 11 assessment tools were recommended as grade B.Conclusion:In contrast,the Questionnaire for Assessing the Childbirth Experience(QACE)is recommended for provisional use,given its relatively good methodological and measurement attributes and appropriate content for evaluation.However,further validation of other measurement properties is needed.
文摘This paper presents a high-security medical image encryption method that leverages a novel and robust sine-cosine map.The map demonstrates remarkable chaotic dynamics over a wide range of parameters.We employ nonlinear analytical tools to thoroughly investigate the dynamics of the chaotic map,which allows us to select optimal parameter configurations for the encryption process.Our findings indicate that the proposed sine-cosine map is capable of generating a rich variety of chaotic attractors,an essential characteristic for effective encryption.The encryption technique is based on bit-plane decomposition,wherein a plain image is divided into distinct bit planes.These planes are organized into two matrices:one containing the most significant bit planes and the other housing the least significant ones.The subsequent phases of chaotic confusion and diffusion utilize these matrices to enhance security.An auxiliary matrix is then generated,comprising the combined bit planes that yield the final encrypted image.Experimental results demonstrate that our proposed technique achieves a commendable level of security for safeguarding sensitive patient information in medical images.As a result,image quality is evaluated using the Structural Similarity Index(SSIM),yielding values close to zero for encrypted images and approaching one for decrypted images.Additionally,the entropy values of the encrypted images are near 8,with a Number of Pixel Change Rate(NPCR)and Unified Average Change Intensity(UACI)exceeding 99.50%and 33%,respectively.Furthermore,quantitative assessments of occlusion attacks,along with comparisons to leading algorithms,validate the integrity and efficacy of our medical image encryption approach.
基金Supported by the Ministry of Science and Technology of the People's Republic of China(2021ZD0201900)Project 5,No.2021ZD0201905Capital’s Funds for Health Improvement and Research,No.CFH 2022-2-4115.
文摘BACKGROUND Brain-computer interface(BCI)technology is rapidly advancing in psychiatry.Informed consent competency(ICC)assessment among psychiatric patients is a pivotal concern in clinical research.AIM To analyze the assessment of ICC and form a framework with multi-dimensional elements involved in ICC of BCI clinical research among psychiatric disorders.METHODS A systematic review of studies regarding ICC assessments of BCI clinical research in patients with six kinds of psychiatric disorders was conducted.A systematic literature search was performed using PubMed,ScienceDirect,and Web of Science.Peer-reviewed articles and full-text studies were included in the analysis.There were no date restrictions,and all studies published up to February 27,2025,were included.RESULTS A total of 103 studies were selected for this review.Fifty-eight studies included ICC factors,and forty-five were classified in ICC related ethical issues of BCI research in six kinds of psychiatric disorders.Executive function impairment is widely recognized as the most significant factor impacting ICC,and processing speed deficits are observed in schizophrenia,mood disorders,and Alzheimer’s disease.Memory dysfunction,particularly episodic and working memory,contributes to compromised ICC.Five core ethical issues in BCI research should be addressed:BCI specificity,vulnerability,autonomy,dynamic ICC,comprehensiveness,and uncertainty.CONCLUSION A Five-Dimensional evaluative framework,including clinical,ethical,sociocultural,legal,and procedural dimensions,is constructed and proposed for future ICC research in BCI clinical research involving psychiatric disorders.
文摘With the shift in the definition of disease from non-alcoholic fatty liver disease(NAFLD)to metabolism-associated fatty liver disease(MAFLD),as well as the rapid evolution of pathological classification and therapeutic targets,traditional clinical teaching models face challenges such as outdated guideline updates,disjointed translation of scientific research,and limited skill training.This study proposes a dynamic training model integrating“guidelines,clinical practice,and scientific research.”Through stratified case-based teaching(e.g.,FibroScan simulator and metabolic sand table),dynamic guideline analysis(comparing old and new evidence),and the integration of scientific thinking(visualization of CAND1 protein mechanism),a teaching system that integrates theory and practice is constructed.Innovatively developed smart assistant tools(AI decision support system,VR liver biopsy simulator)and a multi-dimensional evaluation system(deviation analysis of diagnosis and treatment pathways,milestone assessment)are used while emphasizing metabolic medicine integration(continuous glucose monitoring and digital therapy)and ethical privacy protection(federated learning framework).This model aims to cultivate students’evidence-based decision-making skills and scientific research transformation thinking through dynamic knowledge base construction and interdisciplinary collaboration,providing sustainable teaching solutions to cope with the rapid iteration of NAFLD diagnosis and treatment.
文摘The principle and the constitution of an intelligent system for on-line and real-time montitoring tool cutting state were discussed and a synthetic sensors schedule combined a new type fluid acoustic emission sensor (AE) with motor current sensor was presented. The parallel communication between control system of machine tools, the monitoring intelligent system,and several decision-making systems for identifying tool cutting state was established It can auto - matically select the sensor way ,monitoring mode and identifying method in machining process- ing so as to build a successful and effective intelligent system for on -line and real-time moni- toring cutting tool states in FMS.
文摘The necessity and feasibility of an expert system for carbide-tool utilization are analyzed and a practical system named CUES(carbide-tool utilization expert system ) is developed and realized. The system concept, module structure, data management, inference strategy and the interface design of the system are discussed in.detail. The system would be useful not only for the preparation of tool bank of FMS or CIMS, but the for the proper application of cemented carbide tools in conventional machining Processes.
文摘Reliable on line cutting tool conditioning monitoring is an essential feature of automatic machine tool and flexible manufacturing system (FMS) and computer integrated manufacturing system (CIMS). Recently artificial neural networks (ANNs) are used for this purpose in conjunction with suitable sensory systems. The present work in Norwegian University of Science and Technology (NTNU) uses back propagation neural networks (BP) and fuzzy neural networks (FNN) to process the cutting tool state data measured with force and acoustic emission (AE) sensors, and implements a valuable on line tool condition monitoring system using the ANNs. Different ANN structures are designed and investigated to estimate the tool wear state based on the fusion of acoustic emission and force signals. Finally, four case studies are introduced for the sensing and ANN processing of the tool wear states and the failures of the tool with practical experiment examples. The results indicate that a tool wear identification system can be achieved using the sensors integration with ANNs, and that ANNs provide a very effective method of implementing sensor integration for on line monitoring of tool wear states and abnormalities.
文摘This paper describes a technology of dynamic display moving image by computer monitor,which is initially used in the design of tool detection system. The paper presents the hardware and software principie and edge detection process. The way of marking edge point coordinates and stability of moving image also is analyzed. The method reforms the conventional design of the 2-D vision detection system. Moreover,it facilitates the design of the systematic mechanical construction,is convenient to compile instrument systemsoftware,and realizes to detect and track display image simultaneously. By the work,the tool detection system is improved to practical application.
文摘Parallel kinematics machine （PKM） is advantageous over the serial machine tools in processing the complex-surface products. A manufacturing service system for PKM is developed to provide the services of the complex-surface machining for potential geographically-dispersed manufacturing enterprises. In order to easily in- tegrate the external system, Web services are used to encapsulate post-processing functions of PKM legacy sys- tems, including compilation, workspace calculation, interfere calibration, and kinematics transformation. A ser- vice-oriented architecture（SOA） is proposed for the cooperative work between the PKM system and its client. The workflow and the function module of this manufacturing service system are presented. An example shows that as a result of SOA and loose coupling, such a Web service-based manufacturing service system is easier to in- tegrate and interoperate with its client. Meanwhile, the system decreases the manufacturing cost and improves the efficiency than its former kind of distributed system.
基金supported by the project“Romanian Hub for Artificial Intelligence-HRIA”,Smart Growth,Digitization and Financial Instruments Program,2021–2027,MySMIS No.334906.
文摘Objective expertise evaluation of individuals,as a prerequisite stage for team formation,has been a long-term desideratum in large software development companies.With the rapid advancements in machine learning methods,based on reliable existing data stored in project management tools’datasets,automating this evaluation process becomes a natural step forward.In this context,our approach focuses on quantifying software developer expertise by using metadata from the task-tracking systems.For this,we mathematically formalize two categories of expertise:technology-specific expertise,which denotes the skills required for a particular technology,and general expertise,which encapsulates overall knowledge in the software industry.Afterward,we automatically classify the zones of expertise associated with each task a developer has worked on using Bidirectional Encoder Representations from Transformers(BERT)-like transformers to handle the unique characteristics of project tool datasets effectively.Finally,our method evaluates the proficiency of each software specialist across already completed projects from both technology-specific and general perspectives.The method was experimentally validated,yielding promising results.
基金National Science and Technology Council,the Republic of China,under grants NSTC 113-2221-E-194-011-MY3 and Research Center on Artificial Intelligence and Sustainability,National Chung Cheng University under the research project grant titled“Generative Digital Twin System Design for Sustainable Smart City Development in Taiwan.
文摘Modern manufacturing processes have become more reliant on automation because of the accelerated transition from Industry 3.0 to Industry 4.0.Manual inspection of products on assembly lines remains inefficient,prone to errors and lacks consistency,emphasizing the need for a reliable and automated inspection system.Leveraging both object detection and image segmentation approaches,this research proposes a vision-based solution for the detection of various kinds of tools in the toolkit using deep learning(DL)models.Two Intel RealSense D455f depth cameras were arranged in a top down configuration to capture both RGB and depth images of the toolkits.After applying multiple constraints and enhancing them through preprocessing and augmentation,a dataset consisting of 3300 annotated RGB-D photos was generated.Several DL models were selected through a comprehensive assessment of mean Average Precision(mAP),precision-recall equilibrium,inference latency(target≥30 FPS),and computational burden,resulting in a preference for YOLO and Region-based Convolutional Neural Networks(R-CNN)variants over ViT-based models due to the latter’s increased latency and resource requirements.YOLOV5,YOLOV8,YOLOV11,Faster R-CNN,and Mask R-CNN were trained on the annotated dataset and evaluated using key performance metrics(Recall,Accuracy,F1-score,and Precision).YOLOV11 demonstrated balanced excellence with 93.0%precision,89.9%recall,and a 90.6%F1-score in object detection,as well as 96.9%precision,95.3%recall,and a 96.5%F1-score in instance segmentation with an average inference time of 25 ms per frame(≈40 FPS),demonstrating real-time performance.Leveraging these results,a YOLOV11-based windows application was successfully deployed in a real-time assembly line environment,where it accurately processed live video streams to detect and segment tools within toolkits,demonstrating its practical effectiveness in industrial automation.The application is capable of precisely measuring socket dimensions by utilising edge detection techniques on YOLOv11 segmentation masks,in addition to detection and segmentation.This makes it possible to do specification-level quality control right on the assembly line,which improves the ability to examine things in real time.The implementation is a big step forward for intelligent manufacturing in the Industry 4.0 paradigm.It provides a scalable,efficient,and accurate way to do automated inspection and dimensional verification activities.
文摘Thermal fatigue and high temperature wear are the two principle failure mechanisms for thixoforming dies. Samples of Inconel 617 and Stellite 6 alloys were submitted to thermal cycling under conditions which approximate thixoforming of steels and to sliding wear tests at 750 ℃. The experimental results thus obtained were compared with those of the X32CrMoV33 hot work tool steel. The Inconel 617 and Stellite 6 samples are much more resistant to oxidation and to softening than the hot work tool steel, providing a superior resistance to thermal fatigue cracking. The wear resistance of the Inconel 617 and Stellite 6 alloys at 750 ℃ is also markedly superior. The adhesive oxides growing slowly on Inconel 617 and Stellite 6 alloys sustain the wear action without spalling and are claimed to be responsible for the superior wear resistance of these alloys at 750 ℃.
文摘A systematic geometric model has been presented for calibration of a newly designed 5-axis turbine blade grinding machine. This machine is designed to serve a specific purpose to attain high accuracy and high efficiency grinding of turbine blades by eliminating the hand grinding process. Although its topology is RPPPR （P： prismatic; R： rotary）, its design is quite distinct from the competitive machine tools. As error quantification is the only way to investigate, maintain and improve its accuracy, calibra- tion is recommended for its performance assessment and acceptance testing. Systematic geometric error modeling technique is implemented and 52 position dependent and position independent errors are identified while considering the machine as five rigid bodies by eliminating the set-up errors of workpiece and cutting tool. 39 of them are found to have influential errors and are accommodated for finding the resultant effect between the cutting tool and the workpiece in workspace volume. Rigid body kinematics techniques and homogenous transformation matrices are used for error synthesis.
文摘The present work compares microstructures of hot work steels made by different processes, that is, by sprayforming,by casting, and a commercially supplied H13 steel. Material benefits are recognized by sprayforming hot working tools such as die inserts for hot forging. The sprayformed hot work steels present a fine and homogeneous microstructure,which implies that, at a similar toughness level, the sprayformed steel can be higher alloyed, so that the thermal fatigue and wear resistance at elevated temperatures can be improved. A series of steels with higher vanadium content than commercial hot work steels are developed. There are no segregation and carbide network problems usually encountered in conventional ingot/forging processed high-vanadium steels. Microstructure and hardness of the new sprayformed steels are studied under different heat treatment conditions. It is justified that these sprayformed steels can be directly used for tooling without high temperature hardening. Sprayforming the tool steels onto a precision ceramic mould is demonstrated to extend the technoeconomical benefits, so that a net shape production tool can be rapidly made.Features of the rapid tooling process are also discussed.
基金Key Development Program of ScienceTechnology of Heilongjiang Province, China (GB05A501)
文摘As a key te..hnology in the field of advanced manufacturing, an open architecture controller is studied. In order to develop an open architecture software-CNC system on personal computer （PC） according to open modular architecture controllers （OMAC）. First, the software and hardware platform is chosen and software realization methodology for the CNC system is determined. Second, static modeling methods of an open architecture controller inclusive of object-oriented （OO） programming technology, dynamic link library （DLL） technology and system modules partition are investigated. Third, the dynamical behavioral modeling and the data flow representation of open architecture controller are discussed, which are both described in hierarchy fmite state machine （FSM） model. Fourth, a reusable software module model is established to develop software function module library. Finally, a 3-axis milling machine tool test-bed, named for HIT-CNC, is successfully designed by means of the constructed software function module library and the system configuring method. The experimental results show that, besides increasing the degree of reusability and openness, application of above-mentioned method- ology leads to significant decrease of development time as well as maintenance cost.
基金supported by National Hi-tech Research and Development Program of China (863 Program, Grant No. 2007AA04Z2443)State Key Laboratory for Man ufacturing Systems Engineering of Xi’an Jiaotong University of China
文摘Off-line programming （OLP） system becomes one of the most important programming modules for the robotic belt grinding process, however there lacks research on increasing the grinding dexterous space depending on the OLP system. A new type of grinding robot and a novel robotic belt grinding workcell are forwarded, and their features are briefly introduced. An open and object-oriented off-line programming system is developed for this robotic belt grinding system. The parameters of the trimmed surface are read from the initial graphics exchange specification （IGES） file of the CAD model of the workpiece. The deBoor-Cox basis function is used to sample the grinding target with local contact frame on the workpiece. The numerical formula of inverse kinematics is set up based on Newton＇s iterative procedure, to calculate the grinding robot configurations corresponding to the grinding targets. After the grinding path is obtained, the OLP system turns to be more effective than the teach-by-showing system. In order to improve the grinding workspace, an optimization algorithm for dynamic tool frame is proposed and performed on the special robotic belt grinding system. The initial tool frame and the interval of neighboring tool frames are defined as the preparation of the algorithm. An optimized tool local frame can be selected to grind the complex surface for a maximum dexterity index of the robot. Under the optimization algorithm, a simulation of grinding a vane is included and comparison of grinding workspace is done before and after the tool frame optimization. By the algorithm, the grinding workspace can be enlarged. Moreover the dynamic tool frame can be considered to add one degree-of-freedom to the grinding kinematical chain, which provides the theoretical support for the improvement of robotic dexterity for the complex surface grinding.
