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Influence of static cartoons combined with dynamic virtual environments on preoperative anxiety of preschool-aged children undergoing surgery 被引量:1
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作者 Ya-Lin Zhang Qi-Ying Zhou +3 位作者 Peng Zhang Lin-Feng Huang Li Jin Zhi-Guo Zhou 《World Journal of Clinical Cases》 SCIE 2024年第22期4947-4955,共9页
BACKGROUND Preschoolers become anxious when they are about to undergo anesthesia and surgery,warranting the development of more appropriate and effective interventions.AIM To explore the effect of static cartoons comb... BACKGROUND Preschoolers become anxious when they are about to undergo anesthesia and surgery,warranting the development of more appropriate and effective interventions.AIM To explore the effect of static cartoons combined with dynamic virtual environments on preoperative anxiety and anesthesia induction compliance in preschool-aged children undergoing surgery.METHODS One hundred and sixteen preschool-aged children were selected and assigned to the drug(n=37),intervention(n=40),and control(n=39)groups.All the children received routine preoperative checkups and nursing before being transferred to the preoperative preparation room on the day of the operation.The drug group received 0.5 mg/kg midazolam and the intervention group treatment consisting of static cartoons combined with dynamic virtual environments.The control group received no intervention.The modified Yale Preoperative Anxiety Scale was used to evaluate the children’s anxiety level on the day before surgery(T0),before leaving the preoperative preparation room(T1),when entering the operating room(T2),and at anesthesia induction(T3).Compliance during anesthesia induction(T3)was evaluated using the Induction Compliance Checklist(ICC).Changes in mean arterial pressure(MAP),heart rate(HR),and respiratory rate(RR)were also recorded at each time point.RESULTS The anxiety scores of the three groups increased variously at T1 and T2.At T3,both the drug and intervention groups had similar anxiety scores,both of which were lower than those in the control group.At T1 and T2,MAP,HR,and RR of the three groups increased.The drug and control groups had significantly higher MAP and RR than the intervention group at T2.At T3,the MAP,HR,and RR of the drug group decreased and were significantly lower than those in the control group but were comparable to those in the intervention group.Both the drug and intervention groups had similar ICC scores and duration of anesthesia induction(T3),both of which were higher than those of the control group.CONCLUSION Combining static cartoons with dynamic virtual environments as effective as medication,specifically midazolam,in reducing preoperative anxiety and fear in preschool-aged children.This approach also improve their compliance during anesthesia induction and helped maintain their stable vital signs. 展开更多
关键词 PRESCHOOL Children Static cartoons combined with dynamic virtual environments Preoperative anxiety COMPLIANCE Anesthesia induction
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Virtual and augmented reality systems and three-dimensional printing of the renal model—novel trends to guide preoperative planning for renal cancer
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作者 Claudia-Gabriela Moldovanu 《Asian Journal of Urology》 CSCD 2024年第4期521-529,共9页
Objective:This study aimed to explore the applications of three-dimensional (3D) technology, including virtual reality, augmented reality (AR), and 3D printing system, in the field of medicine, particularly in renal i... Objective:This study aimed to explore the applications of three-dimensional (3D) technology, including virtual reality, augmented reality (AR), and 3D printing system, in the field of medicine, particularly in renal interventions for cancer treatment.Methods:A specialized software transforms 2D medical images into precise 3D digital models, facilitating improved anatomical understanding and surgical planning. Patient-specific 3D printed anatomical models are utilized for preoperative planning, intraoperative guidance, and surgical education. AR technology enables the overlay of digital perceptions onto real-world surgical environments.Results:Patient-specific 3D printed anatomical models have multiple applications, such as preoperative planning, intraoperative guidance, trainee education, and patient counseling. Virtual reality involves substituting the real world with a computer-generated 3D environment, while AR overlays digitally created perceptions onto the existing reality. The advances in 3D modeling technology have sparked considerable interest in their application to partial nephrectomy in the realm of renal cancer. 3D printing, also known as additive manufacturing, constructs 3D objects based on computer-aided design or digital 3D models. Utilizing 3D-printed preoperative renal models provides benefits for surgical planning, offering a more reliable assessment of the tumor's relationship with vital anatomical structures and enabling better preparation for procedures. AR technology allows surgeons to visualize patient-specific renal anatomical structures and their spatial relationships with surrounding organs by projecting CT/MRI images onto a live laparoscopic video. Incorporating patient-specific 3D digital models into healthcare enhances best practice, resulting in improved patient care, increased patient satisfaction, and cost saving for the healthcare system. 展开更多
关键词 three-dimensional model three-dimensional printing Augmented reality virtual reality
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Effects of virtual agents on interaction efficiency and environmental immersion in MR environments
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作者 Yihua BAO Jie GUO +2 位作者 Dongdong WENG Yue LIU Zeyu TIAN 《虚拟现实与智能硬件(中英文)》 EI 2024年第2期169-179,共11页
Background Physical entity interactions in mixed reality(MR)environments aim to harness human capabilities in manipulating physical objects,thereby enhancing virtual environment(VEs)functionality.In MR,a common strate... Background Physical entity interactions in mixed reality(MR)environments aim to harness human capabilities in manipulating physical objects,thereby enhancing virtual environment(VEs)functionality.In MR,a common strategy is to use virtual agents as substitutes for physical entities,balancing interaction efficiency with environmental immersion.However,the impact of virtual agent size and form on interaction performance remains unclear.Methods Two experiments were conducted to explore how virtual agent size and form affect interaction performance,immersion,and preference in MR environments.The first experiment assessed five virtual agent sizes(25%,50%,75%,100%,and 125%of physical size).The second experiment tested four types of frames(no frame,consistent frame,half frame,and surrounding frame)across all agent sizes.Participants,utilizing a head mounted display,performed tasks involving moving cups,typing words,and using a mouse.They completed questionnaires assessing aspects such as the virtual environment effects,interaction effects,collision concerns,and preferences.Results Results from the first experiment revealed that agents matching physical object size produced the best overall performance.The second experiment demonstrated that consistent framing notably enhances interaction accuracy and speed but reduces immersion.To balance efficiency and immersion,frameless agents matching physical object sizes were deemed optimal.Conclusions Virtual agents matching physical entity sizes enhance user experience and interaction performance.Conversely,familiar frames from 2D interfaces detrimentally affect interaction and immersion in virtual spaces.This study provides valuable insights for the future development of MR systems. 展开更多
关键词 Mixed reality virtual agents Interaction performance environmental immersion virtual environments
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Application of Virtual Reality Technology in Constructing Virtual Tourism Environment 被引量:1
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作者 郭立萍 李光霞 董硕 《Journal of Landscape Research》 2010年第7期75-78,共4页
Virtual tourism is the application of virtual reality technology in tourism industry,in which the key is to construct lifelike virtual environment.This paper introduces several main methods in producing virtual enviro... Virtual tourism is the application of virtual reality technology in tourism industry,in which the key is to construct lifelike virtual environment.This paper introduces several main methods in producing virtual environment,such as landform formation with the help of height field method,construction of complicated three-dimensional models in virtual environment through 3DS MAX,construction of lifelike tree models using Billboard technique and Cross Billboard technique,and adoption of texture mapping,LOD(level of detail),and collision testing technique to increase sense of reality in virtual environment.Finally a lifelike virtual tourism environment is realized under the context of Visual C++6.0 through OpenGL. 展开更多
关键词 virtual REALITY technology virtual TOURISM virtual environment OPENGL
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The Use of Virtual Learning Environment in Chinese Higher Education 被引量:1
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作者 谢苑苑 《海外英语》 2014年第14期103-104,共2页
The paper analyzes the current condition of the use of virtual learning environment(VLE) in Zhejiang University of Chinese Medicine. It is indicated that students show a positive attitude toward this technology, but t... The paper analyzes the current condition of the use of virtual learning environment(VLE) in Zhejiang University of Chinese Medicine. It is indicated that students show a positive attitude toward this technology, but the use of it fails to meet students' perception. In light of this, recommendations are made with a view to enhance the use of VLE. 展开更多
关键词 virtual LEARNING environment CHINESE STUDENTS HIGH
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COLLISION AVOIDANCE DECISION-MAKING MODEL OF MULTI-AGENTS IN VIRTUAL DRIVING ENVIRONMENT WITH ANALYTIC HIERARCHY PROCESS 被引量:4
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作者 LU Hong YI Guodong +1 位作者 TAN Jianrong LIU Zhenyu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第1期47-52,共6页
Collision avoidance decision-making models of multiple agents in virtual driving environment are studied. Based on the behavioral characteristics and hierarchical structure of the collision avoidance decision-making i... Collision avoidance decision-making models of multiple agents in virtual driving environment are studied. Based on the behavioral characteristics and hierarchical structure of the collision avoidance decision-making in real life driving, delphi approach and mathematical statistics method are introduced to construct pair-wise comparison judgment matrix of collision avoidance decision choices to each collision situation. Analytic hierarchy process (AHP) is adopted to establish the agents' collision avoidance decision-making model. To simulate drivers' characteristics, driver factors are added to categorize driving modes into impatient mode, normal mode, and the cautious mode. The results show that this model can simulate human's thinking process, and the agents in the virtual environment can deal with collision situations and make decisions to avoid collisions without intervention. The model can also reflect diversity and uncertainly of real life driving behaviors, and solves the multi-objective, multi-choice ranking priority problem in multi-vehicle collision scenarios. This collision avoidance model of multi-agents model is feasible and effective, and can provide richer and closer-to-life virtual scene for driving simulator, reflecting real-life traffic environment more truly, this model can also promote the practicality of driving simulator. 展开更多
关键词 Analytic hierarchy process (AHP) Collision avoidance Decision-making model Driving simulator virtual driving environment Agent Driving behavior
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A Hierarchical Framework for Visualising and Simulating Supply Chains in Virtual Environments 被引量:3
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作者 Hai-Yan Zhang Institute of Engineering Mechanics, China Earthquake Administration, 29 Xuefu Road, Harbin 150018, PRC School of Computing, University of Derby, Kedleston Road, Derby DE22 1GB, UK Zheng-Xu Zhao Department of Instrumentation Science and Engineering, Southeast University, Nanjing 210096, PRC School of Mechanical & Manufacturing Engineering, Shandong University, Jinan 250061, PRC School of Computing, University of Derby, Kedleston Road, Derby DE22 1GB, UK 《International Journal of Automation and computing》 EI 2005年第2期144-154,共11页
This paper presents research into applying virtual environment (VE) technology to supply chain management (SCM). Our research work has employed virtual manufacturing environments to represent supply chain nodes to sim... This paper presents research into applying virtual environment (VE) technology to supply chain management (SCM). Our research work has employed virtual manufacturing environments to represent supply chain nodes to simulate processes and activities in supply chain management. This will enable those who are involved in these processes and activities to gain an intuitive understanding of them, so as to design robust supply chains and make correct decisions at the right time. A framework system and its hierarchical structure for visualising and simulating supply chains in virtual environments are reported and detailed in this paper. 展开更多
关键词 virtual environments supply chains 3D visualising SIMULATING WEB based systems
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Realization of Reconfigurable Virtual Environments for Virtual Testing 被引量:2
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作者 Wen-Yan Wu Zheng-Xu Zhao 《International Journal of Automation and computing》 EI 2005年第1期25-36,共12页
This paper presents the design and implementation of reconfigurable virtual environments (VEs) for virtual testing. It proposes a hybrid design approach that is derived from a so-called integration and composition of ... This paper presents the design and implementation of reconfigurable virtual environments (VEs) for virtual testing. It proposes a hybrid design approach that is derived from a so-called integration and composition of the reconfiguration strategy. The designing process has thus evolved from binding virtual objects using reconfiguration rules within the context of virtual testing scenarios. Therefore reconfigurable virtual environments are established with improved flexibility and scalability, tailored to a wide range of virtual testing applications. Those virtual environments integrate virtual testing scenarios, data acquisition, databases, rule mapping and application interfaces, which yield modular testing functions and an open-ended system architecture with a set of extensible interface tools to realize data exchange within reconfigurable VEs. This enables virtual testing scenarios to be reconfigured interactively based on real time data and communication between virtual environments and real environments. A virtual testing application has been implemented using reconfigurable VEs. Keywords Virtual environment - virtual testing - reconfigurable virtual reality Wenyan Wu graduated from Dalian University of Technology, China, with BSc and MSc in 1988 and 1991 respectively. She earned her PhD degree from University of Derby, UK, in 2002. She had taught and researched in Harbin Institute of Technology, China and De Montfort University, UK. She is currently a senior lecturer in simulation and virtual reality at Staffordshire University, UK. Her research interests include computer graphics, Virtual Reality and Augmented Reality system, advanced interface, modelling and simulation, distribution system.Zhengxu Zhao BSc, MSc, PhD, CEng, CITP, MBCS, full Professor in Applied Computing, Director of Virtual Reality Centre. He is also a Cheng Kong Scholar Project Professor in Virtual Reality Technology and Director of Virtual Reality Research Centre at the Southeast University, P R China. Professor Zhao’s research interests include computing graphics and VR systems, industrial process simulation, CIM and manufacturing management systems. 展开更多
关键词 virtual environment virtual testing reconfigurable virtual reality
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Generation and Control of Game Virtual Environment 被引量:2
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作者 Myeong Won Lee Jae Moon Lee 《International Journal of Automation and computing》 EI 2007年第1期25-29,共5页
In this paper, we present a framework for the generation and control of an Internet-based 3-dimensional game virtual environment that allows a character to navigate through the environment. Our framework includes 3-di... In this paper, we present a framework for the generation and control of an Internet-based 3-dimensional game virtual environment that allows a character to navigate through the environment. Our framework includes 3-dimensional terrain mesh data processing, a map editor, scene processing, collision processing, and walkthrough control. We also define an environment-specific semantic information editor, which can be applied using specific location obtained from the real world. Users can insert text information related to the characters real position in the real world during navigation in the game virtual environment. 展开更多
关键词 virtual environment virtual reality 3D game 3D navigation 3D scene management.
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Microstructure modeling and virtual test of asphalt mixture based on three-dimensional discrete element method 被引量:3
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作者 马涛 张德育 +2 位作者 张垚 赵永利 黄晓明 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第6期1525-1534,共10页
The objective of this work is to model the microstructure of asphalt mixture and build virtual test for asphalt mixture by using Particle Flow Code in three dimensions(PFC^(3D))based on three-dimensional discrete elem... The objective of this work is to model the microstructure of asphalt mixture and build virtual test for asphalt mixture by using Particle Flow Code in three dimensions(PFC^(3D))based on three-dimensional discrete element method.A randomly generating algorithm was proposed to capture the three-dimensional irregular shape of coarse aggregate.And then,modeling algorithm and method for graded aggregates were built.Based on the combination of modeling of coarse aggregates,asphalt mastic and air voids,three-dimensional virtual sample of asphalt mixture was modeled by using PFC^(3D).Virtual tests for penetration test of aggregate and uniaxial creep test of asphalt mixture were built and conducted by using PFC^(3D).By comparison of the testing results between virtual tests and actual laboratory tests,the validity of the microstructure modeling and virtual test built in this study was verified.Additionally,compared with laboratory test,the virtual test is easier to conduct and has less variability.It is proved that microstructure modeling and virtual test based on three-dimensional discrete element method is a promising way to conduct research of asphalt mixture. 展开更多
关键词 asphalt mixture microstructure modeling virtual test discrete element method three-dimensional method
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Science Letters:Dynamic concision for three-dimensional reconstruction of human organ built with virtual reality modelling language (VRML) 被引量:3
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作者 禹正杨 郑树森 +2 位作者 陈雷霆 何晓乾 王建军 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2005年第7期611-616,共6页
This research studies the process of 3D reconstruction and dynamic concision based on 2D medical digital images using virtual reality modelling language (VRML) and JavaScript language, with a focus on how to realize t... This research studies the process of 3D reconstruction and dynamic concision based on 2D medical digital images using virtual reality modelling language (VRML) and JavaScript language, with a focus on how to realize the dynamic concision of 3D medical model with script node and sensor node in VRML. The 3D reconstruction and concision of body internal organs can be built with such high quality that they are better than those obtained from the traditional methods. With the function of dynamic concision, the VRML browser can offer better windows for man-computer interaction in real-time environment than ever before. 3D reconstruction and dynamic concision with VRML can be used to meet the requirement for the medical observation of 3D reconstruction and have a promising prospect in the fields of medical imaging. 展开更多
关键词 virtual Reality Modelling Language (VRML) Direct texture mapping three-dimensional reconstruction Dynamic concision
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Three-dimensional visualization and virtual reality simulation role in hepatic surgery:Further research warranted 被引量:3
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作者 Faiza Ahmed Vinay Jahagirdar +1 位作者 Sravya Gudapati Mohamad Mouchli 《World Journal of Gastrointestinal Surgery》 SCIE 2022年第7期723-726,共4页
Artificial intelligence(AI)is the study of algorithms that enable machines to analyze and execute cognitive activities including problem solving,object and word recognition,reduce the inevitable errors to improve the ... Artificial intelligence(AI)is the study of algorithms that enable machines to analyze and execute cognitive activities including problem solving,object and word recognition,reduce the inevitable errors to improve the diagnostic accuracy,and decision-making.Hepatobiliary procedures are technically complex and the use of AI in perioperative management can improve patient outcomes as discussed below.Three-dimensional(3D)reconstruction of images obtained via ultrasound,computed tomography scan or magnetic resonance imaging,can help surgeons better visualize the surgical sites with added depth perception.Preoperative 3D planning is associated with lesser operative time and intraoperative complications.Also,a more accurate assessment is noted,which leads to fewer operative complications.Images can be converted into physical models with 3D printing technology,which can be of educational value to students and trainees.3D images can be combined to provide 3D visualization,which is used for preoperative navigation,allowing for more precise localization of tumors and vessels.Nevertheless,AI enables surgeons to provide better,personalized care for each patient. 展开更多
关键词 Artificial intelligence three-dimensional printing Liver surgery virtual reality Preoperative planning SIMULATION
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An Intelligent Agent Based on Virtual Geographic Environment System 被引量:2
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作者 SHENDayong LINHui +3 位作者 GONGJianhua ZHAOYibin FANGZhaobao GUOZhongyang 《Geo-Spatial Information Science》 2004年第2期113-116,共4页
On the basis of previous work, this paper designs an intelligent agent based on virtual geographic environment (VGE) system that is characterized by huge data, rapid computation, multi\|user, multi\|thread and intelli... On the basis of previous work, this paper designs an intelligent agent based on virtual geographic environment (VGE) system that is characterized by huge data, rapid computation, multi\|user, multi\|thread and intelligence and issues challenges to traditional GIS models and algorithms. The new advances in software and hardware technology lay a reliable basis for system design, development and application. 展开更多
关键词 virtual geographic environment intelligent agent system design
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Architecture of HLA Based Distributed Virtual Geographic Environment 被引量:2
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作者 XU Bingli LIN Hui GONG Jianhua 《Geo-Spatial Information Science》 2006年第2期127-134,共8页
Integrating the theory of distributed virtual geographic environment (DVGE) and high level architecture(HLA), the architecture of DVGE based on HLA is designed. The data flow and the object models of the architecture ... Integrating the theory of distributed virtual geographic environment (DVGE) and high level architecture(HLA), the architecture of DVGE based on HLA is designed. The data flow and the object models of the architecture are also discussed. The architecture basically meets the need of DVGE in real-time communication, distribution, collaboration, reusing and interoperation, expansion, and standard. 展开更多
关键词 distributed virtual geographic environment high level architecture runtime infrastructure ARCHITECTURE
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Creation and Evaluation of a Multi-sensory Virtual Assembly Environment 被引量:1
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作者 Adrian R L Travis 《International Journal of Automation and computing》 EI 2008年第2期163-173,共11页
The multi-modal information presentation, integrated into the virtual environment (VE), has potential for stimulating different senses, improving the user's impression of immersion, and increasing the amount of inf... The multi-modal information presentation, integrated into the virtual environment (VE), has potential for stimulating different senses, improving the user's impression of immersion, and increasing the amount of information that is accepted and processed by the user's perception system. The increase of the useful feedback information may reduce the user's cognitive load, thus enhancing the user's efficiency and performance while interacting with VEs. This paper presents our creation of a multi-sensory virtual assembly environment (VAE) and the evaluation of the effects of multi-sensory feedback on the usability. The VAE brings together complex technologies such as constraint-based assembly simulation, optical motion tracking technology, and real-time 3D sound generation technology around a virtual reality workbench and a common software platform. The usability evaluation is in terms of its three attributes: efficiency of use, user satisfaction, and reliability. These are addressed by using task completion times (TCTs), questionnaires, and human performance error rates (HPERs), respectively. Two assembly tasks have been used to perform the experiments, using sixteen participants. The outcomes showed that the multi-sensory feedback could improve the usability. They also indicated that the integrated feedback offered better usability than either feedback used in isolation. Most participants preferred the integrated feedback to either feedback (visual or auditory) or no feedback. The participants' comments demonstrated that nonrealistic or inappropriate feedback had negative effects on the usability, and easily made them feel frustrated. The possible reasons behind the outcomes are also analysed by using a unifying human computer interaction framework. The implications, concluded from the outcomes of this work, can serve as useful guidelines for improving VE system design and implementation. 展开更多
关键词 USABILITY virtual environment (VE) assembly simulation multi-sensory feedback task performance
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A Mobile Agent-Based Prototype of HeterogeneousDistributed Virtual Environment Systems 被引量:1
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作者 Ji Qingge(Dept. of Computer Science & Engineering, Harbin Institute of Technology, 150001, P. R. China)Wang Dongmu(Beijing Simulation Center, 100854, P. R. China)Hong Bingrong(Dept. of Computer Science & Engineering, Harbin Institute of Technology, 150001 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2000年第2期61-65,共5页
Mobile agents provide a new method for the distributed computation. This paper presents the advantages of using mobile agents in a distributed virtual environment (DVE) system, and describes the architecture of hetero... Mobile agents provide a new method for the distributed computation. This paper presents the advantages of using mobile agents in a distributed virtual environment (DVE) system, and describes the architecture of heterogeneous computer's distributed virtual environment system (HCWES) designed to populate some mobile agents as well as stationary agents. Finally, the paper introduces how heterogeneous computer network communication is to be realized. 展开更多
关键词 Distributed virtual environment Mobile agent Distributed computing
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Using GIS Data to Build Informed Virtual Geographic Environments (IVGE) 被引量:2
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作者 Mehdi Mekni 《Journal of Geographic Information System》 2013年第6期548-558,共11页
In this paper, we propose a novel approach to automatically building Informed Virtual Geographic Environments (IVGE) using data provided by Geographic Information Systems (GIS). The obtained IVGE provides 2D and 3D ge... In this paper, we propose a novel approach to automatically building Informed Virtual Geographic Environments (IVGE) using data provided by Geographic Information Systems (GIS). The obtained IVGE provides 2D and 3D geographic information for visualization and simulation purposes. Conventional VGE approaches are generally built upon a grid-based representation, raising the well-known problems of the lack of accuracy of the localized data and the difficulty to merge data with multiple semantics. On the contrary, our approach uses a topological model and provides an exact representation of GIS data, allowing an accurate geometrical exploitation. Moreover, our model can merge semantic information, even if spatially overlapping. In addition, the proposed IVGE contains spatial information which can be enhanced thanks to a geometric abstraction method. We illustrate this model with an application which automatically extracts the required data from standard GIS files and allows a user to navigate and retrieve information from the computed IVGE. 展开更多
关键词 GEOGRAPHIC INFORMATION System (GIS) INFORMED virtual GEOGRAPHIC environments (IVGE) MULTI-AGENT Geo-Simulation (MAGS)
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SFC placement and dynamic resource allocation based on VNF performance-resource function and service requirement in cloud-edge environment
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作者 HAN Yingchao MENG Weixiao FAN Wentao 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第4期906-921,共16页
With the continuous development of network func-tions virtualization(NFV)and software-defined networking(SDN)technologies and the explosive growth of network traffic,the requirement for computing resources in the netw... With the continuous development of network func-tions virtualization(NFV)and software-defined networking(SDN)technologies and the explosive growth of network traffic,the requirement for computing resources in the network has risen sharply.Due to the high cost of edge computing resources,coordinating the cloud and edge computing resources to improve the utilization efficiency of edge computing resources is still a considerable challenge.In this paper,we focus on optimiz-ing the placement of network services in cloud-edge environ-ments to maximize the efficiency.It is first proved that,in cloud-edge environments,placing one service function chain(SFC)integrally in the cloud or at the edge can improve the utilization efficiency of edge resources.Then a virtual network function(VNF)performance-resource(P-R)function is proposed to repre-sent the relationship between the VNF instance computing per-formance and the allocated computing resource.To select the SFCs that are most suitable to deploy at the edge,a VNF place-ment and resource allocation model is built to configure each VNF with its particular P-R function.Moreover,a heuristic recur-sive algorithm is designed called the recursive algorithm for max edge throughput(RMET)to solve the model.Through simula-tions on two scenarios,it is verified that RMET can improve the utilization efficiency of edge computing resources. 展开更多
关键词 cloud-edge environment virtual network function(VNF)performance-resource(P-R)function edge resource allo-cation
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Generation of 3D Virtual Geographic Environment Based on Laser Scanning Technique 被引量:1
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作者 DUJie CHENXiaoyong FumioYamazaki 《Geo-Spatial Information Science》 2003年第3期37-42,共6页
This paper demonstrates an experiment on the generation of 3D virtual geographic environment on the basis of experimental flight laser scanning data by a set of algorithms and methods that were developed to automatica... This paper demonstrates an experiment on the generation of 3D virtual geographic environment on the basis of experimental flight laser scanning data by a set of algorithms and methods that were developed to automatically interpret range images for extracting geo-spatial features and then to reconstruct geo-objects. The algorithms and methods for the interpretation and modeling of laser scanner data include triangulated-irregular-network (TIN)-based range image interpolation; mathematical-morphology (MM)-based range image filtering, feature extraction and range image segmentation, feature generalization and optimization, 3D objects reconstruction and modeling; computer-graphics (CG)-based visualization and animation of geographic virtual reality environment. 展开更多
关键词 laser scanning data virtual geographic environment (VGE) urban disaster
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Three-dimensional virtual-real mapping of aircraft autom atic spray operation and online simulation monitoring 被引量:3
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作者 Shiguang QIU Shuntao LIU +1 位作者 Deshuai KONG Qichang HE 《Virtual Reality & Intelligent Hardware》 2019年第6期611-621,共11页
Background This study aims at addressing the lack of closed-loop feedback optimization enabling tool in aircraft automatic spraying systems;we systematically analyze a three-dimensional(3D)virtual-real mapping techniq... Background This study aims at addressing the lack of closed-loop feedback optimization enabling tool in aircraft automatic spraying systems;we systematically analyze a three-dimensional(3D)virtual-real mapping technique,namely the digital twin technique,used by the automatic spraying system.Methods With the sensors installed in the spraying system,the spraying working parameters are collected online and are used for driving the 3D virtual spraying system to realize the total-factor monitoring of the spraying operation.Furthermore,the operation-evaluation model is applied for analyzing and managing the key indexes of the spraying quality;once the data value of the key indexes exceeds a threshold,the operation shall be optimized automatically.Results This approach can effectively support the high-efficiency analysis,evaluation,and optimization of the spraying process. 展开更多
关键词 Digital twin AIRCRAFT Automatic spraying virtual reality virtual environment
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