The concepts of “digital twins”, “3D real scene”, “metacosm” and others were the technical paths for building digital cities with the development of emerging surveying and mapping science and technology, which w...The concepts of “digital twins”, “3D real scene”, “metacosm” and others were the technical paths for building digital cities with the development of emerging surveying and mapping science and technology, which was to build a digital and virtualized city that matched the real physical world, to achieve a one-to-one correspondence between all elements of the physical world and the digital virtual world. And one of its basic geographic information data was a highly similar, virtual simulation of the 3D real scene. After exploring the traditional manual 3DsMax modeling, UAV low-altitude digital oblique photogrammetry modeling, airborne laser scanning modeling and other single modeling technologies, this paper discussed the 3D digital modeling technology used by the UAV airborne laser scanning point cloud and low-altitude digital oblique photogrammetry for complementary integration, constructing the 3D scene of the digital city. This paper expounded the technical route and production process of 3D digital modeling, in order to provide technical references for related projects.展开更多
The term ＂twin cities＂ refers to a program in which cities from different places in the world form a ＂twinning＂ alliance that serves as a setting for educational, cultural, political, and social collaborations （G...The term ＂twin cities＂ refers to a program in which cities from different places in the world form a ＂twinning＂ alliance that serves as a setting for educational, cultural, political, and social collaborations （Grosspietsch 2009）. The purpose of the program is to promote the twin cities in all aspects of life （Jayne, Hubbard, and Bell 2013） and facilitate a feeling of belonging and identity among their residents （Ogawa 2012）. In the current study, the cities of Beer Sheva and Nahariya were taken as case studies for examining the contribution of the program to promoting residents＇ feeling of belonging to their Jewish identity. Specifically, the current study attempted to examine the effect of town of residence and age group on feeling of belonging, and whether familiarity with the Twin Cities program affected the feeling of belonging to Jewish identity, in the assumption that residents familiar with the program would report a stronger feeling of belonging than residents not familiar with it. The study included 147 participants aged 17-64, of them 80 residents of Beer Sheva and 67 of Nahariya. All the participants were recruited to the study voluntarily and were requested to complete an online self-report questionnaire examining feeling of belonging to Jewish identity. Moreover, an interview was conducted with the representative of the delegations at the Amal school in Nahariya, to reaffirm the findings. The research findings refuted the main research assumption that the Twin Cities program would influence the feeling of belonging. In fact, the current study indicates that no correlation was found between feeling of belonging and any of the research measures, aside from religiosity. Furthermore, and in contrast to the hypothesis, the research findings indicate that participants who were not familiar with the program reported a stronger feeling of belonging than participants who were familiar with it. Due to the surprising findings, the current study raises the possibility that the Twin Cities program is undergoing a process of change and thus promotes individual values more than collective values. This contention changes the essential purpose of the program and this is the significance of the current study.展开更多
To understand the current application and development of 3D modeling in Digital Twins(DTs),abundant literatures on DTs and 3D modeling are investigated by means of literature review.The transition process from 3D mode...To understand the current application and development of 3D modeling in Digital Twins(DTs),abundant literatures on DTs and 3D modeling are investigated by means of literature review.The transition process from 3D modeling to DTs modeling is analyzed,as well as the current application of DTs modeling in various industries.The application of 3D DTs modeling in theelds of smartmanufacturing,smart ecology,smart transportation,and smart buildings in smart cities is analyzed in detail,and the current limitations are summarized.It is found that the 3D modeling technology in DTs has broad prospects for development and has a huge impact on all walks of life and even human lifestyles.At the same time,the development of DTs modeling relies on the development and support capabilities of mature technologies such as Big Data,Internet of Things,Cloud Computing,Articial Intelligence,and game technology.Therefore,although some results have been achieved,there are still limitations.This work aims to provide a good theoretical support for the further development of 3D DTs modeling.展开更多
Digital twins for wide-areas(DT-WA)can model and predict the physical world with high fidelity by incorporating an artificial intelligence(AI)model.However,the AI model requires an energy-consuming updating process to...Digital twins for wide-areas(DT-WA)can model and predict the physical world with high fidelity by incorporating an artificial intelligence(AI)model.However,the AI model requires an energy-consuming updating process to keep pace with the dynamic environment,where studies are still in infancy.To reduce the updating energy,this paper proposes a distributed edge cooperation and data collection scheme.The AI model is partitioned into multiple sub-models deployed on different edge servers(ESs)co-located with access points across wide-area,to update distributively using local sensor data.To reduce the updating energy,ESs can choose to become either updating helpers or recipients of their neighboring ESs,based on sensor quantities and basic updating convergencies.Helpers would share their updated sub-model parameters with neighboring recipients,so as to reduce the latter updating workload.To minimize system energy under updating convergency and latency constraints,we further propose an algorithm to let ESs distributively optimize their cooperation identities,collect sensor data,and allocate wireless and computing resources.It comprises several constraint-release approaches,where two child optimization problems are solved,and designs a largescale multi-agent deep reinforcement learning algorithm.Simulation shows that the proposed scheme can efficiently reduce updating energy compared with the baselines.展开更多
文摘The concepts of “digital twins”, “3D real scene”, “metacosm” and others were the technical paths for building digital cities with the development of emerging surveying and mapping science and technology, which was to build a digital and virtualized city that matched the real physical world, to achieve a one-to-one correspondence between all elements of the physical world and the digital virtual world. And one of its basic geographic information data was a highly similar, virtual simulation of the 3D real scene. After exploring the traditional manual 3DsMax modeling, UAV low-altitude digital oblique photogrammetry modeling, airborne laser scanning modeling and other single modeling technologies, this paper discussed the 3D digital modeling technology used by the UAV airborne laser scanning point cloud and low-altitude digital oblique photogrammetry for complementary integration, constructing the 3D scene of the digital city. This paper expounded the technical route and production process of 3D digital modeling, in order to provide technical references for related projects.
文摘The term ＂twin cities＂ refers to a program in which cities from different places in the world form a ＂twinning＂ alliance that serves as a setting for educational, cultural, political, and social collaborations （Grosspietsch 2009）. The purpose of the program is to promote the twin cities in all aspects of life （Jayne, Hubbard, and Bell 2013） and facilitate a feeling of belonging and identity among their residents （Ogawa 2012）. In the current study, the cities of Beer Sheva and Nahariya were taken as case studies for examining the contribution of the program to promoting residents＇ feeling of belonging to their Jewish identity. Specifically, the current study attempted to examine the effect of town of residence and age group on feeling of belonging, and whether familiarity with the Twin Cities program affected the feeling of belonging to Jewish identity, in the assumption that residents familiar with the program would report a stronger feeling of belonging than residents not familiar with it. The study included 147 participants aged 17-64, of them 80 residents of Beer Sheva and 67 of Nahariya. All the participants were recruited to the study voluntarily and were requested to complete an online self-report questionnaire examining feeling of belonging to Jewish identity. Moreover, an interview was conducted with the representative of the delegations at the Amal school in Nahariya, to reaffirm the findings. The research findings refuted the main research assumption that the Twin Cities program would influence the feeling of belonging. In fact, the current study indicates that no correlation was found between feeling of belonging and any of the research measures, aside from religiosity. Furthermore, and in contrast to the hypothesis, the research findings indicate that participants who were not familiar with the program reported a stronger feeling of belonging than participants who were familiar with it. Due to the surprising findings, the current study raises the possibility that the Twin Cities program is undergoing a process of change and thus promotes individual values more than collective values. This contention changes the essential purpose of the program and this is the significance of the current study.
文摘To understand the current application and development of 3D modeling in Digital Twins(DTs),abundant literatures on DTs and 3D modeling are investigated by means of literature review.The transition process from 3D modeling to DTs modeling is analyzed,as well as the current application of DTs modeling in various industries.The application of 3D DTs modeling in theelds of smartmanufacturing,smart ecology,smart transportation,and smart buildings in smart cities is analyzed in detail,and the current limitations are summarized.It is found that the 3D modeling technology in DTs has broad prospects for development and has a huge impact on all walks of life and even human lifestyles.At the same time,the development of DTs modeling relies on the development and support capabilities of mature technologies such as Big Data,Internet of Things,Cloud Computing,Articial Intelligence,and game technology.Therefore,although some results have been achieved,there are still limitations.This work aims to provide a good theoretical support for the further development of 3D DTs modeling.
基金supported by National Key Research and Development Program of China(2020YFB1807900).
文摘Digital twins for wide-areas(DT-WA)can model and predict the physical world with high fidelity by incorporating an artificial intelligence(AI)model.However,the AI model requires an energy-consuming updating process to keep pace with the dynamic environment,where studies are still in infancy.To reduce the updating energy,this paper proposes a distributed edge cooperation and data collection scheme.The AI model is partitioned into multiple sub-models deployed on different edge servers(ESs)co-located with access points across wide-area,to update distributively using local sensor data.To reduce the updating energy,ESs can choose to become either updating helpers or recipients of their neighboring ESs,based on sensor quantities and basic updating convergencies.Helpers would share their updated sub-model parameters with neighboring recipients,so as to reduce the latter updating workload.To minimize system energy under updating convergency and latency constraints,we further propose an algorithm to let ESs distributively optimize their cooperation identities,collect sensor data,and allocate wireless and computing resources.It comprises several constraint-release approaches,where two child optimization problems are solved,and designs a largescale multi-agent deep reinforcement learning algorithm.Simulation shows that the proposed scheme can efficiently reduce updating energy compared with the baselines.
