期刊:
Wireless Personal Communications,2023年128(1):741-741 ISSN:0929-6212
通讯作者:
Weihong Kuang
作者机构:
[Xiaobo Min] School of Metallurgy and Environment, Central South University, Changsha, China;[Weihong Kuang] College of Humanities, Hunan City University, Yiyang, China
通讯机构:
[Weihong Kuang] C;College of Humanities, Hunan City University, Yiyang, China
作者机构:
[Sheng, Haiquan; Zhou, Lv; Chen, Yukai; Xian, Lingxiao; Ma, Shubian] Guilin Univ Technol, Coll Geomatics & Geoinformat, Guilin 541004, Peoples R China.;[Huang, Changjun] Hunan City Univ, Sch Municipal & Surveying Engn, Yiyang 413000, Peoples R China.;[Yang, Fei] China Univ Min & Technol Beijing, Geosci & Survey Engn Coll, Beijing 100083, Peoples R China.
通讯机构:
[Lv Zhou] C;College of Geomatics and Geoinformation, Guilin University of Technology, Guilin 541004, China<&wdkj&>Author to whom correspondence should be addressed.
关键词:
InSAR;persistent scatterer;Beijing;plain;Sentinel-1A;time series
摘要:
Surface subsidence is a serious threat to human life, buildings and traffic in Beijing. Surface subsidence is closely related to human activities, and human activities in Beijing area showed a decreasing trend during the Corona Virus Disease 2019 (COVID-19). To study surface subsidence in Beijing before and after the COVID-19 outbreak and its causes, a total of 51 Sentinel-1A SAR images covering Beijing from January 2018 to April 2022 were selected to derive subsidence information by Time Series Interferometry Synthetic Aperture Radar (TS-InSAR). The results of surface subsidence in Beijing demonstrate that Changping, Chaoyang, Tongzhou and Daxing Districts exhibited the most serious subsidence phenomenon before the COVID-19 outbreak. The four main subsidence areas form an anti-Beijing Bay that surrounds other important urban areas. The maximum subsidence rate reached −57.0 mm/year. After the COVID-19 outbreak, the main subsidence area was separated into three giant subsidence funnels and several small subsidence funnels. During this period, the maximum subsidence rate was reduced to −43.0 mm/year. Human activity decrease with the COVID-19 outbreak. This study effectively analysed the influence of natural factors on surface subsidence after excluding most of the human factors. The following conclusions are obtained from the analysis: (1) Groundwater level changes, Beijing’s geological structure and infrastructure construction are the main reasons for surface subsidence in Beijing. (2) Seasonal changes in rainfall and temperature indirectly affect groundwater level changes, thereby affecting surface subsidence in the area. (3) The COVID-19 outbreak in early 2020 reduced the payload of Beijing’s transportation facilities. It also slowed down the progress of various infrastructure construction projects in Beijing. These scenarios affected the pressure on the soft land base in Beijing and reduced the surface subsidence trend to some extent.
作者机构:
[Xie, Liang; Lin, Xiang; Li, Zhe; Liu, Zhezheng; Jiang, Jishui] Cent South Univ, Sch Architecture & Art, Changsha 410075, Peoples R China.;[Xie, Liang; Lin, Xiang; Li, Zhe; Liu, Zhezheng; Jiang, Jishui] Cent South Univ, Hist Heritage Conservat Res Ctr, Changsha 410075, Peoples R China.;[Jiang, Jishui] Hunan City Univ, Sch Architecture & Urban Planning, Yiyang 413000, Peoples R China.
通讯机构:
[Li, Z ] C;Cent South Univ, Sch Architecture & Art, Changsha 410075, Peoples R China.;Cent South Univ, Hist Heritage Conservat Res Ctr, Changsha 410075, Peoples R China.
关键词:
western Hunan region;Dong;traditional settlement;fire prevention study;Pyrosim simulation
期刊:
Energy Science & Engineering,2023年11(1):192-205 ISSN:2050-0505
通讯作者:
Changqing Chen<&wdkj&>Yali Wang<&wdkj&>Changqing Chen Changqing Chen Changqing Chen<&wdkj&>Yali Wang Yali Wang Yali Wang
作者机构:
[Chen, Qing Chang; Huang, Liang Zhi] Hunan City Univ, Coll Elect & Informat Engn, Yiyang, Peoples R China.;[Chen, Qing Chang; Zhou, Kui] Hunan Bridge Technol Co LTD, Changsha, Peoples R China.;[Wang, Yali] Changsha Univ Sci & Technol, Sch Econ & Management, Changsha, Peoples R China.;[Wang, Yali] Changsha Univ Sci & Technol, Changsha 410076, Hunan, Peoples R China.;[Chen, Qing Chang] Hunan City Coll, Yiyang 413000, Hunan, Peoples R China.
通讯机构:
[Changqing Chen; Changqing Chen Changqing Chen Changqing Chen] C;[Yali Wang; Yali Wang Yali Wang Yali Wang] S;College of Electrical and Information Engineering, Hunan City University, Yiyang, China<&wdkj&>Hunan Bridge Technology Co., LTD., Changsha, China<&wdkj&>School of Economics and Management, Changsha University of Science and Technology, Changsha, China
关键词:
energy storage;frequency regulation;model predictive control;recovery of SOC;wind farm
摘要:
To further improve the frequency regulation stability of wind farm, and optimize the state of charge (SOC) basepoint, charge and discharge rate and recovery capacity of energy storage. In an isolated, off-grid state, a two-layer optimization method is proposed, taking into account the frequency regulation reliability and SOC adaptive adjustment of the wind storage. In the upper layer, the model predictive control theory is adopted to optimize the energy-storage frequency regulation output power with the goal of minimizing the wind storage frequency regulation power deviation. While solving the problem of low-frequency regulation reliability of wind farm, the SOC recovery basepoint and frequency regulation power of energy storage are optimized. At the SOC optimization layer, based on the upper SOC recovery basis point, we propose a dynamic recovery method for energy-storage SOC that considers both the SOC recovery demand and grid-bearing capacity, to determine the energy-storage recovery power. By determining the frequency regulation or recovery power, we propose a calculation method to optimize the energy-storage charge and discharge coefficients as per the SOC for avoiding excessive charging and discharging. The simulation results show that, under continuous disturbance, the root-mean-square deviations of the proposed method is 80.13% and 62.63% lower than those of the fixed K and SOC methods, respectively. Furthermore, the proposed method exhibits the best SOC maintenance effect.
作者机构:
[Xiuxiu Yue; Yitong Yang; Qin Liang; Ruiren Tang; Xiangzhi Song] College of Chemistry & Chemical Engineering, Central South University, Changsha, 410083, China;College of Materials & Chemical Engineering, Hunan City University, Yiyang, 413000, China;[Fengpei Qi] College of Chemistry & Chemical Engineering, Central South University, Changsha, 410083, China<&wdkj&>College of Materials & Chemical Engineering, Hunan City University, Yiyang, 413000, China
通讯机构:
[Ruiren Tang; Xiangzhi Song] C;College of Chemistry & Chemical Engineering, Central South University, Changsha, 410083, China
摘要:
This study examines the impact of confirmatory psychology (CP) on the e-commerce (EC) platform purchasing of sporting products by consumers. The evolution of network communication technologies has produced EC. This study used literature and mathematical statistics to assess the consumption data of sports products purchased by consumers who purchase sports products. By descriptive analysis, variables such as CP are partitioned into dimensions, and hypotheses regarding the relationship between variables are formulated. The study found significant positive associations (P< 0.01) between normative conformity and customers' purchase intentions and between informational conformity and consumers' buying intentions. The interaction variable significantly benefits purchase intent (coefficient standard = 0.045, P< 0.001). Interaction elements showed a statistically significant positive impact on purchase intent (coefficient standard = 0.18, P <0.001). The study has theoretical ramifications that contribute to the body of knowledge. Moreover, the practical consequences of this research are essential for improving the EC platform offerings.
关键词:
parametric analysis;tandem compound piles;bearing capacity;discrete element method;finite difference method
摘要:
The tandem compound piles are a combination of a granular column in the deep section and a concrete pile in the shallow section. This method effectively utilizes the consolidation and densification effects of the granular column, as well as the cementation strength of the concrete material. The granular column acts as a consolidation path, aiding in the densification of the surrounding soil. On the other hand, the concrete pile prevents the bulging deformation that commonly happens in granular columns during field construction. To study the bearing capacity and deformation of the improved foundation with tandem compound piles, a coupled continuum-discrete numerical model was developed in this study. The accuracy of the model was confirmed by comparing its results with experimental measurements. Additionally, a parametric study was conducted, considering three influential factors: (1) cushion thickness and modulus, (2) length, modulus, diameter, and spacing of the tandem compound pile, and (3) soil modulus. The results indicated that reducing the cushion thickness and increasing the cushion modulus allowed the pile to bear more loads. Moreover, increasing the length and modulus of the deep section of the pile reduced deformation and improved the bearing capacity. The pile modulus, however, had a limited effect on enhancing the bearing capacity. It is important to maintain a critical pile spacing of at least twice the pile diameter. Finally, a high modulus of the underlying stratum led to higher vertical and radial stresses in the pile.
期刊:
Frontiers in Environmental Science,2023年11:1270921 ISSN:2296-665X
通讯作者:
Ning, QM
作者机构:
[Ji, Qianfu; Yang, Hua; Zhou, Hui; Song, Qidi; Lai, Nan] Hunan Prov Terr Space Survey & Monitoring Inst, Changsha, Peoples R China.;[Ning, Qimeng; Zeng, Zhiwei; Ning, QM] Hunan City Univ, Coll Architecture & Urban Planning, Yiyang, Peoples R China.
通讯机构:
[Ning, QM ] H;Hunan City Univ, Coll Architecture & Urban Planning, Yiyang, Peoples R China.
关键词:
Urban-water coupling;Water ecological space;Resilience control;digitalization;Dongting Lake area
摘要:
Introduction: The construction of digital governance of national land space depends greatly on the development of a digital model for robust control of water and ecological space. However, how changes to the urban-water coupling relationships affect the resilience control of water ecological space is rarely reported. Methods: The evolution characteristics of urban and water space in the study area from 2000 to 2020 and the correlation between them are analyzed based on the grid analysis using InVEST and Moran’I methods. Based on the theory of human-environment interaction territorial system to provide a theoretical framework to explain the urban and water space. We used digital to construct an resilience control framework in the Dongting Lake area based on the correlation between the urban and water space. Results: The results show that: 1) From 2000 to 2020, the geographical evolution of towns and cities in the research area displayed obvious spatial variation in intensity, indicating a process of expansion and change. The regional and temporal fluctuations of the water conservation function are significant. The mountainous areas in the east, south, and northwest are where the high values of the water conservation function are primarily found. These regions have more vegetation, which increases the water conservation function. 2) According to the results of local binary spatial autocorrelation analysis, it can be seen that from 2000 to 2020, the high-high agglomeration of town space and water-related is mainly distributed in Linxiang City, Yueyang County, Miluo City, Li County, and Yiyang City, and the low-low agglomeration is mainly distributed in Dongting Lake, Datong Lake, and along the Yangtze River. 3) Based on how urban spatial evolution affects water ecological space, we construct a theoretical framework of urban-water coupling and establish a digital model of water ecological space resilience control in the Dongting Lake area from four perspectives: threshold, visualization, dynamics, and intelligence.
关键词:
Semiconductors;Nanocomposites;Coaxial CdS@ZnO nanowire array;Photodegradation;Methylene blue
摘要:
Herein, a novel coaxial CdS@ZnO nanowire array catalyst was synthesized by magnetron sputtering and hy-drothermal method. The optimum photocatalytic composite was obtained by controlling the ratio of CdS and ZnO. Take methylene blue (MB) as the model, the CdS@ZnO nanowire array (CdS@ZnO-10) exhibited strong photocatalytic solid activity, and the highest adsorption and photodegradation rate of MB reached 90.38 % in 50 min and 99.13 % in 120 min under simulated sunlight illumination. The mechanism of the heterojunction interface affecting photocatalytic performance was studied. Therefore, the synthesis approach could offer new design and controllable construction of coaxial structure for organic dye pollutant degradation.
作者机构:
[Zhong, Dou; Liu, Jing; Wang, YK; Wang, Yukui; Zhang, Dan; Hu, Zhangqi] Hunan City Univ, Coll Civil Engn, Yiyang 413099, Peoples R China.;[Wang, YK; Wang, Yukui] Hunan City Univ, Key Lab Green Bldg & Intelligent Construct, Higher Educ Inst Hunan Prov, Yiyang 413000, Peoples R China.;[Liu, Jing; Zhang, Dan; Hu, Zhangqi] Hunan City Univ, Hunan Engn Res Ctr Dev & Applicat Ceramsite Concre, Yiyang 413099, Peoples R China.
通讯机构:
[Wang, YK ] H;Hunan City Univ, Coll Civil Engn, Yiyang 413099, Peoples R China.;Hunan City Univ, Key Lab Green Bldg & Intelligent Construct, Higher Educ Inst Hunan Prov, Yiyang 413000, Peoples R China.
关键词:
Introduction;Materials and Methods;Results;Discussion;Conclusion;Abstract;Data Availability;Additional Points;Ethical Approval;Consent;Disclosure;Conflicts of Interests;Authors’ Contributions;Funding Statement;Acknowledgements;Acknowledgments;Supplementary Materials;Reference;Dataset Description;Dataset Files;Abstract;Introduction;Introduction and Materials;Introduction and Methods;Materials;Materials and Methods;Methods;Results;Discussion;Results and Discussion;Discussion and Conclusion;Results and Conclusion;Conclusion;Conclusions;Data Availability;Additional Points;Ethical Approval;Consent;Disclosure;Conflicts of Interest;Authors’ Contributions;Funding Statement;Acknowledgements;Supplementary Materials;References;Appendix;Abbreviations;Preliminaries;Introduction and Preliminaries;Notation;Proof of Theorem;Proofs;Analysis of Results;Examples;Numerical Example;Applications;Numerical Simulation;Model;Model Formulation;Systematic Palaeontology;Nomenclatural Acts;Taxonomic Implications;Experimental;Synthesis;Overview;Characterization;Background;Experimental;Theories;Calculations;Model Verification;Model Implementation;Geographic location;Study Area;Geological setting;Data Collection;Field Testing;Data and Sampling;Dataset;Literature Review;Related Works;Related Work;System Model;Methods and Data;Experimental Results;Results and Analysis;Evaluation;Implementation;Case Presentation;Case Report;Search Terms;Case Description;Case Series;Background;Limitations;Additional Points;Case;Case 1;Case 2 etc.;Concern Details;Retraction Details;Copyright;Related Articles
摘要:
In order to study seismic design process of RC (reinforced concrete) column components considering the effect of earthquake duration, the degradation law of capacity under random amplitude hysteresis history was conducted by the research group, and the estimation method for the energy dissipation capacity of RC column components was suggested. Furthermore, the correlation between the stiffness decay index and energy dissipation capacity, hysteresis histories, and structural parameters was proposed, and the performance classification criteria based on the stiffness decay index was established. On this basis, the connection between the stiffness decay index and structural parameters and seismic parameters was established, and the seismic design process of RC column components in SDOF (single degree of freedom) system was proposed. The research indicated that the proposed seismic design process based on stiffness decay index can effectively consider the effect of earthquake duration. The stiffness decay index is more suitable for defining structural damage than deformation index and Park-Ang index. The stiffness decay index establishes quantitative relationships with seismic parameters and structural parameters, facilitating performance-based design in engineering practice. The increase in earthquake duration exacerbates the damage of RC column components, and this effect is more pronounced at the beginning of the earthquake and gradually decreases over time.
摘要:
Hemicyanine dyes, with a tunable optical site and high wavelength tailorability, are of significant importance in the fields of sensing and diagnosis. Following the discovery of the near-infrared (NIR) (650–900 nm) fluorescent dyes Changsha (CS) and Huda (HD) by our group, remarkable progress has been made in the development of hemicyanine-based probes for in vivo imaging and detecting. In this review, we summarize the key contributions made by our group in developing long-wavelength (650–1700 nm) hemicyanines and utilizing them to construct functional probes. Finally, potential drawbacks and future prospects of hemicyanine dyes/probes are discussed.
1 Introduction
2 Changsha (CS) Dyes
3 Huda (HD) Dyes
4 Construction of Hemicyanine Fluorophores in the NIR-II Region
5 Summary and Outlook
期刊:
Internet Technology Letters,2023年 ISSN:2476-1508
通讯作者:
Yuanqing Li
作者机构:
[Yuanqing Li] School of Physical Education, Huanghuai University, Zhumadian, China;[Juan Liu] School of Physical Education, Hunan City University, Yiyang, China
通讯机构:
[Yuanqing Li] S;School of Physical Education, Huanghuai University, Zhumadian, China
摘要:
Abstract Yoga, as a kind of body building exercise, has always been loved by people. However, many people suffer from yoga training injuries due to long‐term incorrect posture and wrong exercise methods. There is an urgent need for a technology to help people detect and improve yoga training methods. Based on the past computer assistance method, this paper started from a new idea, and adopted the method of multi‐sensor information fusion to detect yoga training, aiming to help the masses better participate in yoga training. In this study, 50 volunteers were invited to participate in the comparative experiment. Based on multi‐sensor information fusion, and by building a human model, the tension and compression data before and after yoga training were compared to analyze the differences before and after calculation. It was concluded that the more sensors, the higher the degree of information fusion, and the lower the yoga training injury index. The injury index of yoga training without multi‐sensor information fusion technology in the early stage was 0.39. With the increase of the number of sensors, the injury index of yoga training has gradually decreased to 0.02, which was more than 5 percentage points lower than that of the previous methods. The experiment showed that the method of yoga training damage detection based on multi‐sensor information fusion was feasible, which also provided a new idea for the research of yoga training injury detection methods.