T At the forefront of energy storage field, developing sodium ion batteries （SIBs） has drew a wide concern due to relatively low cost and abundant resource, comparing with lithium ion batteries （LIBs）. Serious vol...T At the forefront of energy storage field, developing sodium ion batteries （SIBs） has drew a wide concern due to relatively low cost and abundant resource, comparing with lithium ion batteries （LIBs）. Serious volume expansion constraints the electrochemical performance of the conver- sion/alloying materials, despite of their high reversible capacities or theoretical capacities. Here, from the perspective of structural designs, we systemat- ically study four types of routes to accommodate volume expansion. Delicate and peculiar nanostructures based on nanocrystallization engineering are widely focused on, covering nanosheet assembly and nanoarray construction. Robust materials such as carbon-based materials can be utilized as the buffer matrix, mitigating the mechanical stress during the charge/discharge process. Besides, recent studies have demonstrated void space reservation in nanostructures was also beneficial for adapting to volume changes. Moreover, for conversion materials, numerous works have confirmed the advanta- geous influence of interlayer spacing regulation. We also explained the superiority and challenges for further giving scope to structural designs. Sketching out the future studies in SIBs, in situ characterizations are supposed to be highlighted, as well as in-depth researches on the stress evolution caused by volume expansion.展开更多
Streets and physical layouts can be inherent in a sustainable city by emphasizing the use of space with planned strategies by promoting the movement of people and social behaviors for enhancing an economic structure.A...Streets and physical layouts can be inherent in a sustainable city by emphasizing the use of space with planned strategies by promoting the movement of people and social behaviors for enhancing an economic structure.An analysis of the space layout is beneficial for defining the urban areas that can affect street behavior.A GIS incorporated with a space syntax can help to propagate the effectiveness of a spatial analysis in a study on urban spaces.The integration of the computational pieces of both a GIS analytical tool and space syntax parameters will stimulate research oriented urban systems and spatial morphologies combined with a spatial database.However,the development of livability can be affected by a set of parameters that define the used space.Thus,this paper was aimed at examining the space syntax parameters for space visualization to evaluate street behavior using the GIS processing and space syntax methods.In this study,a spatial analysis was used to generate spatial information on traffic volume,while a space syntax was used to test the street behavior.Also,a predictive analysis was conducted to identify the correlation between traffic behavior and a set of parameters.The results showed that integration and direct visibility were significant to the traffic volume.Most of the streets that were linked to the commercial area showed high integration and direct visibility,which increased by more than half,compared with the unlinked areas.Based on the statistical analysis,both parameters recorded aprobability of less than 5%.The results showed that any space designed with a continuous,direct and clear traffic volume will lead to increased integration and direct visibility,thus influencing a natural vehicle movement.展开更多
Volume visualization can not only illustrate overall distribution but also inner structure and it is an important approach for space environment research.Space environment simulation can produce several correlated var...Volume visualization can not only illustrate overall distribution but also inner structure and it is an important approach for space environment research.Space environment simulation can produce several correlated variables at the same time.However,existing compressed volume rendering methods only consider reducing the redundant information in a single volume of a specific variable,not dealing with the redundant information among these variables.For space environment volume data with multi-correlated variables,based on the HVQ-1d method we propose a further improved HVQ method by compositing variable-specific levels to reduce the redundant information among these variables.The volume data associated with each variable is divided into disjoint blocks of size 43 initially.The blocks are represented as two levels,a mean level and a detail level.The variable-specific mean levels and detail levels are combined respectively to form a larger global mean level and a larger global detail level.To both global levels,a splitting based on a principal component analysis is applied to compute initial codebooks.Then,LBG algorithm is conducted for codebook refinement and quantization.We further take advantage of progressive rendering based on GPU for real-time interactive visualization.Our method has been tested along with HVQ and HVQ-1d on high-energy proton flux volume data,including>5,>10,>30 and>50 MeV integrated proton flux.The results of our experiments prove that the method proposed in this paper pays the least cost of quality at compression,achieves a higher decompression and rendering speed compared with HVQ and provides satisficed fidelity while ensuring interactive rendering speed.展开更多
文摘T At the forefront of energy storage field, developing sodium ion batteries （SIBs） has drew a wide concern due to relatively low cost and abundant resource, comparing with lithium ion batteries （LIBs）. Serious volume expansion constraints the electrochemical performance of the conver- sion/alloying materials, despite of their high reversible capacities or theoretical capacities. Here, from the perspective of structural designs, we systemat- ically study four types of routes to accommodate volume expansion. Delicate and peculiar nanostructures based on nanocrystallization engineering are widely focused on, covering nanosheet assembly and nanoarray construction. Robust materials such as carbon-based materials can be utilized as the buffer matrix, mitigating the mechanical stress during the charge/discharge process. Besides, recent studies have demonstrated void space reservation in nanostructures was also beneficial for adapting to volume changes. Moreover, for conversion materials, numerous works have confirmed the advanta- geous influence of interlayer spacing regulation. We also explained the superiority and challenges for further giving scope to structural designs. Sketching out the future studies in SIBs, in situ characterizations are supposed to be highlighted, as well as in-depth researches on the stress evolution caused by volume expansion.
基金This work was supported by the Malaysia Ministry of Higher Education(MOHE)[600-IRMI/FRGS/3(205/2019)The authors would like to thank Universiti Teknologi MARA(UiTM)for its support and partial funding of the study through the FRGS Grant(600-IRMI/FRGS/3(205/2019)).The authors would also like to thank all the staff members of the Surveying Science and Geomatics Department for the postprocessing equipment support,and the individuals who were involved in and contributed to this study.
文摘Streets and physical layouts can be inherent in a sustainable city by emphasizing the use of space with planned strategies by promoting the movement of people and social behaviors for enhancing an economic structure.An analysis of the space layout is beneficial for defining the urban areas that can affect street behavior.A GIS incorporated with a space syntax can help to propagate the effectiveness of a spatial analysis in a study on urban spaces.The integration of the computational pieces of both a GIS analytical tool and space syntax parameters will stimulate research oriented urban systems and spatial morphologies combined with a spatial database.However,the development of livability can be affected by a set of parameters that define the used space.Thus,this paper was aimed at examining the space syntax parameters for space visualization to evaluate street behavior using the GIS processing and space syntax methods.In this study,a spatial analysis was used to generate spatial information on traffic volume,while a space syntax was used to test the street behavior.Also,a predictive analysis was conducted to identify the correlation between traffic behavior and a set of parameters.The results showed that integration and direct visibility were significant to the traffic volume.Most of the streets that were linked to the commercial area showed high integration and direct visibility,which increased by more than half,compared with the unlinked areas.Based on the statistical analysis,both parameters recorded aprobability of less than 5%.The results showed that any space designed with a continuous,direct and clear traffic volume will lead to increased integration and direct visibility,thus influencing a natural vehicle movement.
基金the Key Research Program of the Chinese Academy of Sciences(ZDRE-KT-2021-3)。
文摘Volume visualization can not only illustrate overall distribution but also inner structure and it is an important approach for space environment research.Space environment simulation can produce several correlated variables at the same time.However,existing compressed volume rendering methods only consider reducing the redundant information in a single volume of a specific variable,not dealing with the redundant information among these variables.For space environment volume data with multi-correlated variables,based on the HVQ-1d method we propose a further improved HVQ method by compositing variable-specific levels to reduce the redundant information among these variables.The volume data associated with each variable is divided into disjoint blocks of size 43 initially.The blocks are represented as two levels,a mean level and a detail level.The variable-specific mean levels and detail levels are combined respectively to form a larger global mean level and a larger global detail level.To both global levels,a splitting based on a principal component analysis is applied to compute initial codebooks.Then,LBG algorithm is conducted for codebook refinement and quantization.We further take advantage of progressive rendering based on GPU for real-time interactive visualization.Our method has been tested along with HVQ and HVQ-1d on high-energy proton flux volume data,including>5,>10,>30 and>50 MeV integrated proton flux.The results of our experiments prove that the method proposed in this paper pays the least cost of quality at compression,achieves a higher decompression and rendering speed compared with HVQ and provides satisficed fidelity while ensuring interactive rendering speed.
