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A State-of-the-Art Survey on Real-Time Issues in Embedded Systems Virtualization 被引量:1
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作者 Zonghua Gu Qingling Zhao 《Journal of Software Engineering and Applications》 2012年第4期277-290,共14页
Virtualization has gained great acceptance in the server and cloud computing arena. In recent years, it has also been widely applied to real-time embedded systems with stringent timing constraints. We present a compre... Virtualization has gained great acceptance in the server and cloud computing arena. In recent years, it has also been widely applied to real-time embedded systems with stringent timing constraints. We present a comprehensive survey on real-time issues in virtualization for embedded systems, covering popular virtualization systems including KVM, Xen, L4 and others. 展开更多
关键词 virtualIZATION Embedded Systems real-TIME SCHEDULING
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mRNA Dependent Virtual-Real Substitutions of Nucleotides in Codons: The Dynamics of Their Meanings in the Genome Language
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作者 P. P. Gariaev E. A. Leonova-Gariaeva 《Open Journal of Genetics》 2019年第4期77-90,共14页
This is an attempt to explain mRNA-dependent non-stationary semantic values of codons (triplets) and nucleotides (letters) in codon composition during protein biosynthesis. This explanation is realized by comparing th... This is an attempt to explain mRNA-dependent non-stationary semantic values of codons (triplets) and nucleotides (letters) in codon composition during protein biosynthesis. This explanation is realized by comparing the different protein codes of various biosystem taxa, and, comparing mitochondrial code with the standard code. An initial mRNA transcriptional virtuality (Virtual-Reality) is transformed into material reality at the level of translation of virtual triplets into real (material) amino acids or into a real stop command of protein biosynthesis. The transformation of virtuality into reality occurs de facto when the linguistic sign1 functions of the codon syhoms are realized in the 3’ nucleotide (wobbling nucleotide according to F. Crick) in the process of protein biosynthesis. This corresponds to the theoretical works of the authors of this article. Despite the illusory appearance of semantic arbitrariness during the operation of ribosomes in the mode of codon semantic non-stationarity, this phenomenon probably provides biosystems with an unusually high level of adaptability to changes in the external environment as well as to internal (mental) dynamics of neuron’s genome in the cerebral cortex. The genome’s non-stationarity properties at the nucleotide, codon, gene and mental levels have fractal structure and corresponding dimensions. The highest form of such fractality (with maximum dimension) is probably realized in the genomic continuum of neurons in the human cerebral cortex through this semantic Virtual-to-Real (VR) codon transcoding with the biosynthesis of short-living semantic proteins, as the equivalents of material thinking-consciousness. In fact, this is the language of the brain’s genome, that is, our own language. In this case, the same thing happens in natural, primarily mental (non-verbal) languages. Their materialization is recorded in vocables (sounding words) and in writing. Such writing is the amino acid sequence in the semantic proteins of the human cerebral cortex. Rapidly decaying, such proteins can leave a long-lasting “so-called” Schr&#246;dinger wave holographic memory in the cerebral cortex. The presented below study is purely theoretical and based on a logical approach. The topic of the study is very complex and is subject to further development. 展开更多
关键词 PROTEIN Biosynthesis PROTEIN Codes CODONS (Triplets) MRNA virtual-real (VR) Transcoding Semantics Thinking Consciousness
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Novel 3-dimensional virtual hepatectomy simulation combined with real-time deformation 被引量:22
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作者 Yukio Oshiro Hiroaki Yano +4 位作者 Jun Mitani Sangtae Kim Jaejeong Kim Kiyoshi Fukunaga Nobuhiro Ohkohchi 《World Journal of Gastroenterology》 SCIE CAS 2015年第34期9982-9992,共11页
AIM:To develop a novel 3-dimensional(3D) virtual hepatectomy simulation software,Liversim,to visualize the real-time deformation of the liver.METHODS:We developed a novel real-time virtual hepatectomy simulation softw... AIM:To develop a novel 3-dimensional(3D) virtual hepatectomy simulation software,Liversim,to visualize the real-time deformation of the liver.METHODS:We developed a novel real-time virtual hepatectomy simulation software program called Liversim. The software provides 4 basic functions:viewing 3D models from arbitrary directions,changing the colors and opacities of the models,deforming the models based on user interaction,and incising the liver parenchyma and intrahepatic vessels based on user operations. From April 2010 through 2013,99 patients underwent virtual hepatectomies that used the conventional software program SYNAPSE VINCENT preoperatively. Between April 2012 and October 2013,11 patients received virtual hepatectomies using the novel software program Liversim; these hepatectomies were performed both preoperatively and at the same that the actual hepatectomy was performed in an operating room. The perioperative outcomes were analyzed between the patients for whom SYNAPSE VINCENT was used and those for whom Liversim wasused. Furthermore,medical students and surgical residents were asked to complete questionnaires regarding the new software.RESULTS:There were no obvious discrepancies(i.e.,the emergence of branches in the portal vein or hepatic vein or the depth and direction of the resection line) between our simulation and the actual surgery during the resection process. The median operating time was 304 min(range,110 to 846) in the VINCENT group and 397 min(range,232 to 497) in the Liversim group(P = 0.30). The median amount of intraoperative bleeding was 510 m L(range,18 to 5120) in the VINCENT group and 470 m L(range,130 to 1600) in the Liversim group(P = 0.44). The median postoperative stay was 12 d(range,6 to 100) in the VINCENT group and 13 d(range,9 to 21) in the Liversim group(P = 0.36). There were no significant differences in the preoperative outcomes between the two groups. Liversim was not found to be clinically inferior to SYNAPSE VINCENT. Both students and surgical residents reported that the Liversim image was almost the same as the actual hepatectomy.CONCLUSION:Virtual hepatectomy with real-time deformation of the liver using Liversim is useful for the safe performance of hepatectomies and for surgical education. 展开更多
关键词 LIVER SURGERY SIMULATION virtual HEPATECtoMY real-
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AVirtual Cloud Storage Architecture for Enhanced Data Security
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作者 M.Antony Joans Kumar C.Christopher Columbus +1 位作者 E.Ben George T.Ajith Bosco Raj 《Computer Systems Science & Engineering》 SCIE EI 2023年第2期1735-1747,共13页
The sensitive data stored in the public cloud by privileged users,such as corporate companies and government agencies are highly vulnerable in the hands of cloud providers and hackers.The proposed Virtual Cloud Storag... The sensitive data stored in the public cloud by privileged users,such as corporate companies and government agencies are highly vulnerable in the hands of cloud providers and hackers.The proposed Virtual Cloud Storage Archi-tecture is primarily concerned with data integrity and confidentiality,as well as availability.To provide confidentiality and availability,thefile to be stored in cloud storage should be encrypted using an auto-generated key and then encoded into distinct chunks.Hashing the encoded chunks ensured thefile integrity,and a newly proposed Circular Shift Chunk Allocation technique was used to determine the order of chunk storage.Thefile could be retrieved by performing the opera-tions in reverse.Using the regenerating code,the model could regenerate the missing and corrupted chunks from the cloud.The proposed architecture adds an extra layer of security while maintaining a reasonable response time and sto-rage capacity.Experimental results analysis show that the proposed model has been tested with storage space and response time for storage and retrieval.The VCSA model consumes 1.5x(150%)storage space.It was found that total storage required for the VCSA model is very low when compared with 2x Replication and completely satisfies the CIA model.The response time VCSA model was tested with different sizedfiles starting from 2 to 16 MB.The response time for storing and retrieving a 2 MBfile is 4.96 and 3.77 s respectively,and for a 16 MBfile,the response times are 11.06 s for storage and 5.6 s for retrieval. 展开更多
关键词 Erasure code regenerating code CRYPtoGRAPHY virtual cloud storage architecture circular shift chunk allocation algorithm
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Optimizing Real-Time Performance of 3D Virtual Mining Environment with MultiGen Creator 被引量:12
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作者 WANGWei-chen JIANGXiao-hong +1 位作者 HANKe-qi HANWen-ji 《Computer Aided Drafting,Design and Manufacturing》 2004年第1期61-69,共9页
System optimization plays a crucial role in developing VR system after 3D modeling, affecting the system's Immersion and Interaction performance enormously. In this article, several key techniques of optimizing a ... System optimization plays a crucial role in developing VR system after 3D modeling, affecting the system's Immersion and Interaction performance enormously. In this article, several key techniques of optimizing a virtual mining system were discussed: optimizing 3D models to keep the polygon number in VR system within target hardware's processing ability; optimizing texture database to save texture memory with perfect visual effect; optimizing database hierarchy structure to accelerate model retrieval; and optimizing LOD hierarchy structure to speed up rendering. 展开更多
关键词 virtual mining system real-time performance OPTIMIZATION MultiGen creator
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Justification and System Arrangement of Virtual Property Rights——Comments on Article No. 127 of General Provisions of the Civil Law
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作者 Li Yan Ge Hongquan 《Contemporary Social Sciences》 2019年第2期1-20,共20页
In the process of formulating the General Provisions of the Civil Law of P. R. China, the attribute of virtual property rights has changed from real rights to non-real rights. Article No. 127 thereof does not clarify ... In the process of formulating the General Provisions of the Civil Law of P. R. China, the attribute of virtual property rights has changed from real rights to non-real rights. Article No. 127 thereof does not clarify the nature of virtual property rights after all, and the place where virtual property is put in the "Civil Rights" chapter of General Provisions of the Civil Law makes the concept even more complex and confusing. The "relationships paradigm" protection of virtual property does not have a definite classification criterion, nor stands opposite to the "rights paradigm." There are two different ways to justify the "theory of virtual property as a real right" under the "rights paradigm" protection, namely, essentialism and consequentialism. The former resulted from utilizing features in a demonstration and identifying disposal rights with real rights, while the latter resulted from adherence to the dichotomy system of property rights comprising real rights and creditor's rights. From the perspective of larceny in Criminal Law and virtual property insurance in The Social Insurance Law, the attribute of virtual property rights is irrelevant to creditor's rights. The attribute of virtual property rights shall be defined as virtual property rights so that it can be included in the system of civil rights. The uniqueness of virtual property is enough to become an object of emerging civil rights; intangible property rights as a superordinate theoretical concept cannot reflect the essence of virtual property rights. The legislative frame of virtual property rights shall be comprised of the subject, object, exercise, publication and change of the rights. 展开更多
关键词 virtual PROPERTY theORY of virtual PROPERTY as a real RIGHT theORY of virtual PROPERTY as a creditor's RIGHT intangible PROPERTY RIGHTS virtual PROPERTY RIGHTS
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Virtualization of Real Estate Industry and Housing Bubbles --Empirical Evidence from China
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作者 Beibei Yan Yizhen Wang 《经济管理学刊(中英文版)》 2019年第1期22-31,共10页
In the last twenty years, China has experienced a rapid development in the real estate industry. The continuous rising house price causes many social and economic problems and draws a lot of attentions from academia, ... In the last twenty years, China has experienced a rapid development in the real estate industry. The continuous rising house price causes many social and economic problems and draws a lot of attentions from academia, business world and government. Many researchers shed light on this problem from different angles, but till today, it hasn’t been fully resolved. In this paper, we try to examine the real estate bubble from a virtual economic perspective. We think that the virtual feature of real estate alters its economic role from a purely living and working place to a financing instrument. We use the newest monthly data of China real estate market from 2006 to 2018 and estimate the relationship between the housing bubble and real estate industry virtualization. We identify a significant positive association between house price index and the purchase price of land in real estate investment. This result suggests that virtual feature of real estate has deepen the bubble problem in the industry and its virtualization degree appears to be closely related to the virtual feature of land and its price proportion to real estate investment. 展开更多
关键词 real ESTATE BUBBLES virtual ECONOMY China HOUSING
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Studies on the Auto-Tuning Variables in Auto-Cruise Vehicle
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作者 Hyunsub Lee Wonsik Lim +3 位作者 Sukwon Cha Hassan Waqas Chunhua Zheng Guoqing Xu 《通讯和计算机(中英文版)》 2016年第2期55-63,共9页
关键词 自动调谐 车辆 巡航 手动调整 汽车 MATLAB 驱动程序 换档模式
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Parallel Sensing in Metaverses: Virtual-Real Interactive Smart Systems for “6S” Sensing 被引量:7
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作者 Yu Shen Yuhang Liu +1 位作者 Yonglin Tian Xiaoxiang Na 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第12期2047-2054,共8页
In the construction of Metaverses,sensors that are referred to as the“bridge of information transmission”,play a key role.The functionality and efficiency of today’s sensors,which operate in a manner similar to phy... In the construction of Metaverses,sensors that are referred to as the“bridge of information transmission”,play a key role.The functionality and efficiency of today’s sensors,which operate in a manner similar to physical sensing,are frequently constrained by their hardware and software.In this research,we proposed the Parallel Sensing framework,which includes background,concept,basic methods and typical application of parallel sensing.In our formulation,sensors are redefined as the integration of real physical sensors and virtual software-defined sensors based on parallel intelligence,in order to boost the performance of the sensors.Each sensor will have a parallel counterpart in the virtual world within the framework of parallel sensing.Digital sensors serve as the brain of sensors and maintain the same properties as physical sensors.Parallel sensing allows physical sensors to operate in discrete time periods to conserve energy,while cloud-based descriptive,predictive,and prescriptive sensors operate continuously to offer compensation data and serve as guardians.To better illustrate parallel sensing concept,we show some example applications of parallel sensing such as parallel vision,parallel point cloud and parallel light fields,both of which are designed by construct virtual sensors to extend small real data to virtual big data and then boost the performance of perception models.Experimental results demonstrate the effective of parallel sensing framework.The interaction between the real and virtual worlds enables sensors to operate actively,allowing them to intelligently adapt to various scenarios and ultimately attain the goal of“Cognitive,Parallel,Crypto,Federated,Social and Ecologic”6S sensing. 展开更多
关键词 Parallel Sensing Parallel Intelligence CPSS Metaverses virtual and real Interaction “6S”Sensing.
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Does the social security fund help non-financial enterprises to transform from the virtual to the real? 被引量:5
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作者 Dapeng Tang Jiamei Wu Zhibin Chen 《China Journal of Accounting Research》 2022年第2期149-171,共23页
At its 19th National Congress,the Communist Party of China vowed to“strengthen the financial sector’s ability to serve the real economy.”However,many studies provide evidence of the opposite trend,a problematic“tr... At its 19th National Congress,the Communist Party of China vowed to“strengthen the financial sector’s ability to serve the real economy.”However,many studies provide evidence of the opposite trend,a problematic“transition from the real to the virtual,”among Chinese enterprises.Meanwhile,the investment efficiency of China’s Social Security Fund(SSF),a public fund,attracts much attention.In this context,we use A-share listed companies in China from2009 to 2018 to study the relationship between holding by the SSF and enterprise financialization.We find that SSF holding significantly inhibits financialization and that this effect is non-linear.Mechanism analysis indicates that SSF holding suppresses enterprises’financialization mainly by improving their governance.Moreover,SSF holding more strongly inhibits small-scale(vs.large-scale),state-owned(vs.non-state-owned),and non-eastern(vs.eastern)enterprises in China.Furthermore,SSF holding can alleviate corporate value impairment caused by financialization.The conclusions enrich theoretical research and provide empirical evidence that may help regulatory authorities to guide investment by enterprises and prevent financial risks. 展开更多
关键词 Social security fund holding(SSF holding) Non-financial enterprises FINANCIALIZATION Transition from the virtual to the real China
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A Remote Real-Time Monitoring System for Power Quality 被引量:1
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作者 黄治清 贺建闽 《Journal of Southwest Jiaotong University(English Edition)》 2003年第1期31-38,共8页
An introduction is made to the composition, design method and engineering application of a remote real time monitoring system of power quality in substations based on internet. With virtual instrument and network tec... An introduction is made to the composition, design method and engineering application of a remote real time monitoring system of power quality in substations based on internet. With virtual instrument and network technique adopted, this system is characterized by good real time property, high reliability, plentiful functions, and so on. It also can be used to monitor the load of a substation, such as electric locomotives. 展开更多
关键词 power quality remote monitoring real time monitoring system virtual instrument
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Systematic design method for PI controller with Virtual Resistor-based Active Damping of LCL filter 被引量:4
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作者 Marwa Ben Said-Romdhane Mohmed Wissem Naouar Ilhem Slama-Belkhodja 《Global Energy Interconnection》 2018年第3期319-329,共11页
The Virtual Resistor based Active Damping(VR-AD) is widely employed in converters connected to the grid via LCL filters in order to mitigate the inherent resonance of the filters. Nevertheless, in digitally controlled... The Virtual Resistor based Active Damping(VR-AD) is widely employed in converters connected to the grid via LCL filters in order to mitigate the inherent resonance of the filters. Nevertheless, in digitally controlled systems, the PWM and the calculating delays modify the system characteristics in terms of frequency and phase, thus destabilizing the system and degrading the VR-AD performances, mainly in low switching frequencies. Moreover, the stability of the system is greatly affected under weak grid operation characterized by large grid impedance variation. This paper solves these problems by proposing a systematic, robust and optimized design procedure of voltage oriented PI control(VOC) with VRAD. The considered design procedure ensures robust control(sufficient stability margins) and high quality of grid current(reduced steady-state error and minimized THD value) despite the negative impact of digital time delay, grid impedance variation and filter parameters change. Simulation and experimental results are presented to show robustness and efficiency of the suggested design procedure. 展开更多
关键词 Digital controllers LCL filter Time delay Grid-connected converters virtual Resistor real Resistor VOC Grid impedance variation Controllers design
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The New Doppler Shift-and-Range Positioning Algorithm for the Global Navigation Satellite System 被引量:2
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作者 季海福 《天文研究与技术》 CSCD 2014年第1期13-18,共6页
关键词 天文学 天文观测 天文台 天文仪器
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Real-time virtual sonography visualization and its clinical application in biliopancreatic disease 被引量:1
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作者 Atsushi Sofuni Takao Itoi +11 位作者 Fumihide Itokawa Takayoshi Tsuchiya Toshio Kurihara Kentaro Ishii Syujiro Tsuji Nobuhito Ikeuchi Reina Tanaka Junko Umeda Ryosuke Tonozuka Mitsuyoshi Honjo Shuntaro Mukai Fuminori Moriyasu 《World Journal of Gastroenterology》 SCIE CAS 2013年第42期7419-7425,共7页
AIM:To evaluate the usefulness of real-time virtual sonography(RVS)in biliary and pancreatic diseases.METHODS:This study included 15 patients with biliary and pancreatic diseases.RVS can be used to observe an ultrasou... AIM:To evaluate the usefulness of real-time virtual sonography(RVS)in biliary and pancreatic diseases.METHODS:This study included 15 patients with biliary and pancreatic diseases.RVS can be used to observe an ultrasound image in real time by merging the ultrasound image with a multiplanar reconstruction computed tomography(CT)image,using pre-scanned CT volume data.The ultrasound used was EUB-8500with a convex probe EUP-C514.The RVS images were evaluated based on 3 levels,namely,excellent,good and poor,by the displacement in position.RESULTS:By combining the objectivity of CT with free scanning using RVS,it was possible to easily interpret the relationship between lesions and the surrounding organs as well as the position of vascular structures.The resulting evaluation levels of the RVS images were12 excellent(pancreatic cancer,bile duct cancer,cholecystolithiasis and cholangiocellular carcinoma)and 3 good(pancreatic cancer and gallbladder cancer).Compared with conventional B-mode ultrasonography and CT,RVS images achieved a rate of 80%superior visualization and 20%better visualization.CONCLUSION:RVS has potential usefulness in objective visualization and diagnosis in the field of biliary and pancreatic diseases. 展开更多
关键词 BILIARY and pancreatic disease COMPUTED tomography-multiplanar reconstruction IMAGE Navigation real-TIME ultrasound IMAGE real-TIME virtual SONOGRAPHY
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Using Mixed Reality as a Simulation Tool in Urban Planning Project for Sustainable Development
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作者 Hisham E1-Shimy Ghada Ahmed Ragheb Amany Ahmed Ragheb 《Journal of Civil Engineering and Architecture》 2015年第7期830-835,共6页
Nowadays, urban design faces complex demands. It has become a necessity to negotiate between stakeholder objectives, the expectations of citizens and the demands of planning. It is desirable to involve the stakeholder... Nowadays, urban design faces complex demands. It has become a necessity to negotiate between stakeholder objectives, the expectations of citizens and the demands of planning. It is desirable to involve the stakeholders and citizens from an early stage in the planning process to enable their different viewpoints to be successfully expressed and comprehended. Therefore, the basic aim of the study was how the MR (mixed reality) application is designed to encourage and improve communication on urban design among stakeholders and citizens? In this paper, we discuss new approaches to visualize urban building and environment alternatives to different stakeholders and provide them with tools to explore different approaches to urban planning in order to support citizen's participation in urban planning with augmented and mixed reality. The major finding of the study is that learning "how these participatory technologies may help build a community of practice around an urban project". And throughout the different experiences, we can learn to assist towards development of a methodology to use the mixed reality as a simulation tool in the enhancement of collaborative interaction in real-Egyptian project. So, we can determine a number of recommendations to deal with new participatory design tools for urban planning projects. 展开更多
关键词 Mixed reality real environment virtual reality augmented reality augmented virtuality MR-tent.
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Life Experience Method of Application Writing under the Internet+ Field
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作者 Li Wang 《Journal of Computer and Communications》 2016年第14期80-88,共10页
Network virtual social life and social life of the intimate contact, gaining experience through the network are growing acceptance of a new kind of practice writing behavior. In this paper, closely related to the new ... Network virtual social life and social life of the intimate contact, gaining experience through the network are growing acceptance of a new kind of practice writing behavior. In this paper, closely related to the new direction of life experience of the Internet age forms, and characteristics of practical writing life experience development under the network environment and study of teaching strategy analysis, think the Internet+ provided by the social forms life mirror, fits the practical writing “material needs” obtaining through the network to the indirect way to gain life experience of social forms, and has become a new kind of practical writing teaching methods. Network life experience is not only a practical writing, and also will use literature writing, news writing, such as writing behavior. 展开更多
关键词 Network Transmission virtual and real Life Experience Teaching and Learning Effects and Countermeasures
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Real Imagination for Virtual World Expo
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《中国会展》 2005年第15期59-59,共1页
关键词 World virtual real Imagination for virtual World Expo
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面向智能制造仿真实验的产线数字孪生建模 被引量:3
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作者 惠记庄 王帅 朱斌 《实验技术与管理》 CAS 北大核心 2024年第1期150-157,共8页
针对智能制造领域人才培养中,实践教学存在的成本高、安全保证难等问题,该研究构建了智能制造仿真实验系统。首先,以智能产线为基础、车间信息化平台为桥梁,融合产线数字孪生技术,构建了面向智能制造仿真实验的数字孪生系统框架;其次,... 针对智能制造领域人才培养中,实践教学存在的成本高、安全保证难等问题,该研究构建了智能制造仿真实验系统。首先,以智能产线为基础、车间信息化平台为桥梁,融合产线数字孪生技术,构建了面向智能制造仿真实验的数字孪生系统框架;其次,对系统中包含的产线物理实体模型、数据采集及车间信息化平台、数字孪生产线的多维度模型及智能制造仿真实验平台展开了详细阐述;最后设计产线生产调度优化实验,验证了该数字孪生仿真实验系统的有效性。 展开更多
关键词 智能制造 数字孪生产线 虚实结合 实验教学
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数字孪生驱动的巷道自动成形截割虚拟调试方法研究 被引量:1
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作者 张旭辉 刘彦徽 +4 位作者 杨文娟 张超 杜昱阳 杨骏豪 杨雯雨 《工矿自动化》 CSCD 北大核心 2024年第7期1-11,31,共12页
针对目前巷道自动成形截割控制调试周期长、调试成本大、安全风险大、成形质量难以评价等问题,提出了一种数字孪生驱动的巷道自动成形截割虚拟调试方法。采用基于即时外观建图(RTAP−MAP)技术重建巷道三维环境,构建掘进机控制系统模型,... 针对目前巷道自动成形截割控制调试周期长、调试成本大、安全风险大、成形质量难以评价等问题,提出了一种数字孪生驱动的巷道自动成形截割虚拟调试方法。采用基于即时外观建图(RTAP−MAP)技术重建巷道三维环境,构建掘进机控制系统模型,形成虚拟调试环境,并利用虚拟传感器技术实现物理空间到虚拟环境状态的精准映射。针对难以量化评估断面成形质量的问题,确立了巷道自动成形截割性能评价方法,以断面成形截割控制过程在数据传输中心的记录为基础,主要对断面成形精度、截割效率与油缸开关次数、硬岩切割调整、超挖欠挖4个评价指标进行计算,从而为深度学习算法的迭代优化提供精准反馈信号,并提出了一种融合强化学习的自动截割控制策略,以提高自动化作业的适应性和精确度。为验证该虚拟调试方法的有效性和准确性,搭建了掘进机自动控制实验平台,并将虚拟调试系统应用于掘进巷道成形截割自动控制程序中。虚拟仿真结果表明:①被调试软件在控制关键点位处的X,Y,Z轴定位误差的最大值分别为74.8,72.93,123.67 mm,说明虚拟调试方法的定位精度达到性能要求。②虚拟样机与物理样机轨迹基本一致,说明该调试方法实现了对物理空间的映射。应用结果表明:①强化学习控制器在虚拟掘进测试中适应了复杂环境,将虚拟传感器输入有效转换为精准控制指令,验证了模拟−现实迁移训练的可行性。通过处理掘进精度和避免超欠挖的实时反馈,控制器学习并优化了策略。②优化后的断面成形截割控制性能得到了提升,根据数据库中控制量时间戳的记录,用时126 s,较优化前耗时减少了8 s。③优化后截割部末端轨迹跟踪最大误差为6.0 mm,较优化前降低了0.3 mm,避免了截割轨迹抖动导致的欠挖,同时使得轨迹和断面更加平滑。 展开更多
关键词 巷道自动成形截割 数字孪生 虚拟调试 虚拟传感器 虚实坐标转换
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元地球与数字孪生:思想突破、技术变革与范式转换 被引量:1
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作者 李三忠 索艳慧 +30 位作者 戴黎明 王亮亮 姜兆霞 曹现志 苏国辉 刘丽军 周建平 李玺瑶 刘洁 朱俊江 乔璐璐 王光增 姜素华 王秀娟 刘琳 管红香 李晓辉 胡军 刘鹏 刘泽 董冬冬 郭玲莉 邹志辉 董昊 钟世华 孙国正 刘洋 于胜尧 吴立新 邹卓延 孙毅 《地学前缘》 EI CAS CSCD 北大核心 2024年第1期46-63,共18页
数字孪生在航天、工业制造领域已应用了20多年,但引入海洋科学还是首次。通过数字孪生技术,实现真实地球与虚拟地球的融合,构建一个真实地球与数字地球的虚实共同体,这里称为“元地球”。本文介绍了元地球与早期提出的数字地球、虚拟地... 数字孪生在航天、工业制造领域已应用了20多年,但引入海洋科学还是首次。通过数字孪生技术,实现真实地球与虚拟地球的融合,构建一个真实地球与数字地球的虚实共同体,这里称为“元地球”。本文介绍了元地球与早期提出的数字地球、虚拟地球、玻璃地球、智慧地球的本质区别,进而突出元地球理念或思想上的巨大突破。基于现今元宇宙BIGANT技术体系,构架跨越地球各圈层的实时、全天候、立体观测感知系统,打通地球系统各圈层动力学模拟隔阂,实现超越现今地球,再现深时地球,实现时空穿越,从而集数字地球、虚拟地球、玻璃地球、智慧地球、现今地球、深时地球的特性于一个共同体,这个深时的虚实共同体就是元地球。这一理念必将催生新的技术范式变革,进而超越现实地球、虚拟地球,开启人类认识地球、探测地球、开发地球的全新方式。在实现研究范式转换的同时,推动元地球的多场景应用,这也必将催生未来的万亿新产业。 展开更多
关键词 元地球 真实地球 虚拟地球 数字地球 数字孪生 地球系统 范式
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