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Discussion on the Application of UAV Aerial Survey Technology in Basic Surveying and Mapping
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作者 YUYue 《外文科技期刊数据库(文摘版)工程技术》 2022年第7期108-111,共4页
Basic surveying and mapping involves a lot of content, which is a systematic and complex work. In actual surveying and mapping, it is necessary not only to improve the accuracy of surveying and mapping, but also to fu... Basic surveying and mapping involves a lot of content, which is a systematic and complex work. In actual surveying and mapping, it is necessary not only to improve the accuracy of surveying and mapping, but also to further improve the efficiency of surveying and mapping. In recent years, UAV technology has developed rapidly, and UAV remote sensing mapping has also become a new surveying and mapping technology. It can use corresponding equipment to control UAVs and photographic equipment to obtain corresponding information. However, the UAV remote sensing mapping technology is still in the initial stage of development at this stage, and further research on practical problems needs to be enhanced when applied in basic surveying and mapping, so as to effectively promote the development of UAV remote sensing mapping technology. 展开更多
关键词 UAV aerial survey TECHNOLOGY basic surveying and mapping APPLICATION
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The Development and Application of Low Temperature Plasma Technology
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《Southwestern Institute of Physics Annual Report》 2006年第1期190-191,共2页
The development and applications of low temperature plasma technology used in surface modification of materials are presented in this paper. Based on plasma sources and ion sources technology, multi-functions ion impl... The development and applications of low temperature plasma technology used in surface modification of materials are presented in this paper. Based on plasma sources and ion sources technology, multi-functions ion implantation and deposition technologies were developed and the related processes are also used to treat different products. The related technologies were translated into industrial productions supported by national research projects. Following the last development of international plasma researches, the standardization and internationalization processes of plasma technologies are executed in our center. 展开更多
关键词 Low temperature plasma Development and application
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Impacts of random negative training datasets on machine learning-based geologic hazard susceptibility assessment
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作者 Hao Cheng Wei Hong +3 位作者 Zhen-kai Zhang Zeng-lin Hong Zi-yao Wang Yu-xuan Dong 《China Geology》 2025年第4期676-690,共15页
This study investigated the impacts of random negative training datasets(NTDs)on the uncertainty of machine learning models for geologic hazard susceptibility assessment of the Loess Plateau,northern Shaanxi Province,... This study investigated the impacts of random negative training datasets(NTDs)on the uncertainty of machine learning models for geologic hazard susceptibility assessment of the Loess Plateau,northern Shaanxi Province,China.Based on randomly generated 40 NTDs,the study developed models for the geologic hazard susceptibility assessment using the random forest algorithm and evaluated their performances using the area under the receiver operating characteristic curve(AUC).Specifically,the means and standard deviations of the AUC values from all models were then utilized to assess the overall spatial correlation between the conditioning factors and the susceptibility assessment,as well as the uncertainty introduced by the NTDs.A risk and return methodology was thus employed to quantify and mitigate the uncertainty,with log odds ratios used to characterize the susceptibility assessment levels.The risk and return values were calculated based on the standard deviations and means of the log odds ratios of various locations.After the mean log odds ratios were converted into probability values,the final susceptibility map was plotted,which accounts for the uncertainty induced by random NTDs.The results indicate that the AUC values of the models ranged from 0.810 to 0.963,with an average of 0.852 and a standard deviation of 0.035,indicating encouraging prediction effects and certain uncertainty.The risk and return analysis reveals that low-risk and high-return areas suggest lower standard deviations and higher means across multiple model-derived assessments.Overall,this study introduces a new framework for quantifying the uncertainty of multiple training and evaluation models,aimed at improving their robustness and reliability.Additionally,by identifying low-risk and high-return areas,resource allocation for geologic hazard prevention and control can be optimized,thus ensuring that limited resources are directed toward the most effective prevention and control measures. 展开更多
关键词 LANDSLIDES Debris flows Collapses Ground fissures Geologic hazard prevention and control ENGINEERING Geologic hazard susceptibility assessment Negative training dataset Average spatial correlation Random forest algorithm Risk and return analysis Geological survey engineering Loess Plateau area
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Pollution and carbon reduction effects of the pilot policy on clean winter heating in Northern China:Evidence from the county level
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作者 Yan Chen Jiaqi Li +1 位作者 Yue Zhang Fan Yang 《Chinese Journal of Population,Resources and Environment》 2025年第1期85-95,共11页
Coal dependence and inefficient decentralized heating have significantly increased China’s energy consumption for winter heating,increasing air pollution and exacerbating the greenhouse effect.In 2017,China implement... Coal dependence and inefficient decentralized heating have significantly increased China’s energy consumption for winter heating,increasing air pollution and exacerbating the greenhouse effect.In 2017,China implemented the Pilot Policy on Clean Winter Heating in Northern China,aiming to achieve high central heating coverage and cleaner energy consumption.Studying the effects of this policy can help promote its implementation and serve as a reference for effective adjustment of the contents in the future.However,few studies have investigated this policy and its carbon reduction effects,and most focus on the provincial or city levels.Therefore,this paper considers the policy’s influence on air pollution and carbon emissions at the county level to provide a precise and comprehensive assessment of the policy effects.We use panel data from 1290 counties in 15 provinces in Northern China from 2014 to 2021,applying a multiperiod difference-in-differences model to quantify the impact of the policy on carbon emissions and air quality in the pilot area.We then conduct a series of tests to demonstrate the robustness of the results and analyze the mechanisms of the policy effects from two perspectives,namely,central heating and natural gas use,through a mediating effect model.Finally,we examine the heterogeneity of policy effects between counties based on geographic location and per capita income levels of rural residents through a moderating effect model.The results reveal that the policy significantly reduces air pollution and carbon emissions in the pilot area by increasing the central heating area and natural gas use.Compared with the central and western regions in the north and areas with low-income rural residents,the policy effects in the eastern regions in the north and areas with high-income rural residents are more pronounced. 展开更多
关键词 Pilot policy on clean winter heating Pollution and carbon reduction Multiperiod difference-in-differences model County-level analysis Northern China
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Performance Analysis of Compound Parabolic Concentration Photothermal and Photoelectricity Device for Soil Heating in Facility Agriculture 被引量:3
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作者 Zehui Chang Yanan Peng +2 位作者 Xuedong Liu Jing Hou Shuaijun Guo 《Transactions of Tianjin University》 EI CAS 2022年第2期144-152,共9页
It is difficult for solanum crops to grow continuously during winter in severe cold regions. Thus, a soil heating system for facility agriculture based on solar concentration technology was proposed, and a novel compo... It is difficult for solanum crops to grow continuously during winter in severe cold regions. Thus, a soil heating system for facility agriculture based on solar concentration technology was proposed, and a novel compound parabolic concentration photothermal and photoelectricity device(CTPV) equipped in the system was designed to address this problem. In accordance with the structure of the device, LightTools optical software was selected to analyze the variation trend of the light escape rate of the device with the diff erent incident angles. On the basis of the calculation results, an experimental test system was used to investigate the relationship of the air temperature of the inlet and the outlet, total output power of the solar cells, and photothermal and photoelectricity efficiency of the device with the operation time during a sunny day. Research results reveal that the light escape rate of the device is 5.36% at an incidence angle of 12°. At a velocity of 1.5 m/s, the maximum air temperature of the outlet can reach 55.6 ℃, and the total output power of the solar cells is 474.4 W. The variation of the total power of the solar cells is consistent with the simulation results. The maximum instantaneous heat collection and the maximum photothermal and photoelectricity efficiency of the device are 306 W and 60.4%, respectively, and the average efficiency is 44.9%. This study can serve as a reference for compound parabolic concentration technology applied for soil heating in facility agricultural soil heating systems. 展开更多
关键词 Facility agriculture Photothermal and photoelectricity CONCENTRATION Soil HEATING
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Resting-state electroencephalography theta predicts neurofeedback treatment 4-month follow-up response in nicotine addiction 被引量:2
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作者 Qiujian Meng Ying Zhu +4 位作者 Ye Yuan Li Yang Jiafang Liu Xiaochu Zhang Junjie Bu 《General Psychiatry》 CSCD 2023年第4期303-311,共9页
Background The high rate of long-term relapse is a major cause of smoking cessation failure.Recently,neurofeedback training has been widely used in the treatment of nicotine addiction;however,approximately 30%of subje... Background The high rate of long-term relapse is a major cause of smoking cessation failure.Recently,neurofeedback training has been widely used in the treatment of nicotine addiction;however,approximately 30%of subjects fail to benefit from this intervention.Our previous randomised clinical trial(RCT)examined cognition-guided neurofeedback and demonstrated a significant decrease in daily cigarette consumption at the 4-month follow-up.However,significant individual differences were observed in the 4-month follow-up effects of decreased cigarette consumption.Therefore,it is critical to identify who will benefit from pre-neurofeedback.Aims We examined whether the resting-state electroencephalography(EEG)characteristics from pre-neurofeedback predicted the 4-month follow-up effects and explored the possible mechanisms.Methods This was a double-blind RCT.A total of 60 participants with nicotine dependence were randomly assigned to either the real-feedback or yoked-feedback group.They underwent 6 min closed-eye resting EEG recordings both before and after two neurofeedback sessions.A follow-up assessment was conducted after 4 months.Results The frontal resting-state theta power spectral density(PSD)was significantly altered in the real-feedback group after two neurofeedback visits.Higher theta PSD in the real-feedback group before neurofeedback was the only predictor of decreased cigarette consumption at the 4-month follow-up.Further reliability analysis revealed a significant positive correlation between theta PSD pre-neurofeedback and post-neurofeedback.A leave-one-out cross-validated linear regression of the theta PSD pre-neurofeedback demonstrated a significant correlation between the predicted and observed reductions in cigarette consumption at the 4-month follow-up.Finally,source analysis revealed that the brain mechanisms of the theta PSD predictor were located in the orbital frontal cortex.Conclusions Our study demonstrated changes in the resting-state theta PSD following neurofeedback training.Moreover,the resting-state theta PSD may serve as a prognostic marker of neurofeedback effects.A higher resting-state theta PSD predicts a better long-term response to neurofeedback treatment,which may facilitate the selection of individualised interventions. 展开更多
关键词 NICOTINE ADDICTION TREATMENT
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Impulsivity-related right superior frontal gyrus as a biomarker of internet gaming disorder 被引量:2
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作者 Pengyu Zhang Yu Pan +10 位作者 Rujing Zha Hongwen Song Cunfeng Yuan Qian Zhao Yi Piao Jiecheng Ren Yijun Chen Peipeng Liang Ran Tao Zhengde Wei Xiaochu Zhang 《General Psychiatry》 CSCD 2023年第4期321-333,共13页
Background Internet gaming disorder(IGD)is a mental health issue that affects individuals worldwide.However,the lack of knowledge about the biomarkers associated with the development of IGD has restricted the diagnosi... Background Internet gaming disorder(IGD)is a mental health issue that affects individuals worldwide.However,the lack of knowledge about the biomarkers associated with the development of IGD has restricted the diagnosis and treatment of this disorder.Aims We aimed to reveal the biomarkers associated with the development of IGD through resting-state brain network analysis and provide clues for the diagnosis and treatment of IGD.Methods Twenty-six patients with IGD,23 excessive internet game users(EIUs)who recurrently played internet games but were not diagnosed with IGD and 29 healthy controls(HCs)performed delay discounting task(DDT)and Iowa gambling task(IGT).Resting-state functional magnetic resonance imaging(fMRI)data were also collected.Results Patients with IGD exhibited significantly lower hubness in the right medial orbital part of the superior frontal gyrus(ORBsupmed)than both the EIU and the HC groups.Additionally,the hubness of the right ORBsupmed was found to be positively correlated with the highest excessive internet gaming degree during the past year in the EIU group but not the IGD group;this might be the protective mechanism that prevents EIUs from becoming addicted to internet games.Moreover,the hubness of the right ORBsupmed was found to be related to the treatment outcome of patients with IGD,with higher hubness of this region indicating better recovery when undergoing forced abstinence.Further modelling analysis of the DDT and IGT showed that patients with IGD displayed higher impulsivity during the decision-making process,and impulsivity-related parameters were negatively correlated with the hubness of right ORBsupmed.Conclusions Our findings revealed that the impulsivity-related right ORBsupmed hubness could serve as a potential biomarker of IGD and provide clues for the diagnosis and treatment of IGD. 展开更多
关键词 INTERNET diagnosis protective
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Grass-livestock balance based grassland ecological carrying capability and sustainable strategy in the Yellow River Source National Park, Tibet Plateau, China
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作者 YU Hui LIU Bin-tao +7 位作者 WANG Gen-xu ZHANG Tong-zuo YANG Yan LU Ya-qiong XU You-xue HUANG Min YANG Yi ZHANG Lv 《Journal of Mountain Science》 SCIE CSCD 2021年第8期2201-2211,共11页
The Yellow River Source National Park(YRSP)is one of the most sensitive and fragile ecological regions in the world.The historical intensive grazing and climate change have resulted in ecological degradation that thre... The Yellow River Source National Park(YRSP)is one of the most sensitive and fragile ecological regions in the world.The historical intensive grazing and climate change have resulted in ecological degradation that threatens the wildlife and livestock.Exploring the sustainable strategy is urgent for policy makers to meet the demands for wild ungulates and livestock.In our study,the grassland ecological carrying capability(GECC)was assessed based on the updated grass-livestock balance that considered the grass competition from wild ungulates.The balances between grass and livestock,and GECC and grassland pressure index(GPI)in the YRSP were measured through overlay analysis and geostatistic analysis.The results showed that:(1)the ratio of livestock to wild ungulates in the research area was approximately 4.56:1,in which the proportion of livestock was 81.75%and the actual number of livestock was 33.84×104 standard sheep units;(2)Under the scenario of minimum grazing utilisation rate,the theoretical grazing capacity and GECC were 37.83×104 standard sheep units and−0.13,respectively.Under the maximum grazing utilisation rate,the theoretical grazing capacity and GECC were 41.93×104 standard sheep units and−0.21,respectively.Since GECC in both scenarios were both less than 0,the grassland was considered to be in surplus and the livestock was not overloaded.However,GPI in the two scenarios were 0.87 and 0.79,respectively,both of which exceeded the warning line of 0.70.Based on GECC,we recommend that the sustainable strategy in YRSP is either to increase the supplementary feeding about 6.40×104 standard sheep units or reduce the grazing livestock by about 3.50×10^(4) standard sheep units. 展开更多
关键词 Yellow River Source National Park Grassland ecological carrying capability Grasslivestock balance
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Compressed Sensing Based on the Single Layer Wavelet Transform for Image Fusion
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作者 Guohui Yang Wude Xu +5 位作者 Bo Zheng Fanglan Ma Xuhui Yang Hongwei Ma Hongxia Zhang Genliang Han 《Journal of Computer and Communications》 2016年第15期107-116,共10页
In this paper, a new method of combination single layer wavelet transform and compressive sensing is proposed for image fusion. In which only measured the high-pass wavelet coefficients of the image but preserved the ... In this paper, a new method of combination single layer wavelet transform and compressive sensing is proposed for image fusion. In which only measured the high-pass wavelet coefficients of the image but preserved the low-pass wavelet coefficient. Then, fuse the low-pass wavelet coefficients and the measurements of high-pass wavelet coefficient with different schemes. For the reconstruction, by using the minimization of total variation algorithm (TV), high-pass wavelet coefficients could be recovered by the fused measurements. Finally, the fused image could be reconstructed by the inverse wavelet transform. The experiments show the proposed method provides promising fusion performance with a low computational complexity. 展开更多
关键词 Image Fusion Compressed Sensing Single Layer Wavelet Transform
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Performance Comparison of CVD Grown Carbon Nanofiber Based on Single-and Multi-Layer Graphene Oxides in Melt-Compounded PA6.6 Nanocomposites
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作者 Elcin Cakal Sarac Leila Haghighi Poudeh +5 位作者 Jamal Seyyed Monfared Zanjani Ilse Letofsky-Papst Fevzi Cakmak Cebeci Ismail Aydin Yusuf Menceloglu Burcu Saner Okan 《Open Journal of Composite Materials》 2019年第2期99-123,共25页
In the present study, newly design hybrid nanostructures were produced by growing long carbon nanofibers (CNF) on single- and multi-layer graphene oxide (GO) sheets in the presence of catalyst by chemical vapor deposi... In the present study, newly design hybrid nanostructures were produced by growing long carbon nanofibers (CNF) on single- and multi-layer graphene oxide (GO) sheets in the presence of catalyst by chemical vapor deposition (CVD). Chemical composition analysis indicated the formation of Fe-C bonds by the deposition of carbon atoms on catalyst surface of Fe2O3 and increasing in C/O atomic ratio confirming CNF growing. These hybrid additives were distributed homogeneously through polyamide 6.6 (PA6.6) chains by high shear thermokinetic mixer in melt phase. Spectroscopic studies showed that the differences in the number of graphene layer in hybrid structures directly affected the crystalline behavior and dispersion state in polymer matrix. Flexural strength and flexural modulus of PA6.6 nanocomposites were improved up to 14.7% and 14% by the integration of 0.5 wt% CNF grown on multi-layer GO, respectively, whereas there was a significant loss in flexural properties of single-layer GO based nanocomposites. Also, the integration of 0.5 wt% multi-layer GO hybrid reinforcement in PA6.6 provided a significant increase in tensile modulus about 24%. Therefore, multi-layer GO with CNF increased the degree of crystallinity in nanocomposites by forming intercalated structure and acted as a nucleating agent causing the improvement in mechanical properties. 展开更多
关键词 Nanoparticles Polyamides NANOCOMPOSITES Mechanical Properties Thermal Properties
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Aggregation-induced T_(1)/T_(2) contrast enhancement for magnetic resonance imaging-guided intraoperative surgery
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作者 Wenbo Sun Bin Yu +5 位作者 Dianshuai Huang Chunhuan Jiang Wei Wang Jianhua Liu Zonghua Wang Lehui Lu 《Science China Chemistry》 SCIE EI CAS CSCD 2024年第6期2046-2055,共10页
Magnetic resonance imaging(MRI)plays an important role in precision medicine that is hampered by the lack of contrast agents with high efficiency and the ability to translate diagnostic accuracy into therapeutic inter... Magnetic resonance imaging(MRI)plays an important role in precision medicine that is hampered by the lack of contrast agents with high efficiency and the ability to translate diagnostic accuracy into therapeutic intervention.Herein,we demonstrate a DNA-based MRI probe that overcomes previous single-mode enhancement and provides a mechanism of action for aggregationinduced dual-modal MRI signal enhancement.A facile method is developed to produce aggregated T_(1)/T_(2)dual-modal NaGdF_(4):Dy@PDA-DNA(PDA=polydopamine)MRI probes.When aggregated,this probe can further amplify MRI signal intensity and exhibit improved geometrical and positional stability in vivo.The performance of the NaGdF_(4):Dy@PDA-DNA MRI probe toward MRI-guided preoperative planning and visualization-guided surgery is verified using an orthotopic tumor-bearing mouse model.The result shows that the rapid metabolism of the degraded probe leads to the mitigation of long-term toxic effects.Therefore,the developed high-performance MRI probe is of great significance for enhancing MRI diagnostic accuracy into precision medical therapeutic interventions. 展开更多
关键词 MRI probe DNA aggregation-induced T_(1)/T_(2)contrast enhancement precision medicine degradable probe
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New method for cotton fractional vegetation cover extraction based on UAV RGB images 被引量:1
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作者 Huanbo Yang Yubin Lan +3 位作者 Liqun Lu Daocai Gong Jianchi Miao Jing Zhao 《International Journal of Agricultural and Biological Engineering》 SCIE CAS 2022年第4期172-180,共9页
As the key principle of precision farming,the distribution of fractional vegetation cover is the basis of crop management within the field serves.To estimate crop FVC rapidly at the farm scale,high temporal-spatial re... As the key principle of precision farming,the distribution of fractional vegetation cover is the basis of crop management within the field serves.To estimate crop FVC rapidly at the farm scale,high temporal-spatial resolution imagery obtained by unmanned aerial vehicle(UAV)was adopted.To verify the application potential of consumer-grade UAV RGB imagery in estimated FVC,blue-green characteristic vegetation index(TBVI)and red-green vegetation index(TRVI)were proposed in this study according to the differences of the gray value among cotton vegetation,soil and shadow in the field.First,two new constructed indices and several published indices were used to extract visible light images and generate greyscale images for each of the visible light vegetation indices.Then,the thresholds of cotton vegetation and non-vegetation pixels were established based on the vegetation index threshold method which combines support vector machine classification and vegetation index.Finally,the accuracy difference in vegetation information extraction between the newly constructed and several published indices was compared.The results show that the accuracy of the information extracted by TRVI is higher than that of subdivision index of other visible light(FVC extraction precision in the first bud stage of cotton:R2=0.832,RMSE=2.307,nRMSE=4.405%;FVC extraction precision in the bud stage of cotton:R2=0.981,RMSE=1.393,nRMSE=1.984%;FVC extraction precision in the flowering stage of cotton:R2=0.893,RMSE=2.101,nRMSE=2.422%;FVC extraction precision in the boll stage of cotton:R2=0.958,RMSE=1.850,nRMSE=2.050%). 展开更多
关键词 COTTON UAV visible light images fractional vegetation cover vegetation index threshold method TRVI TBVI
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