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Improving the Accuracy of Vegetation Index Retrieval for Biomass by Combining Ground-UAV Hyperspectral Data-A New Method for Inner Mongolia Typical Grasslands
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作者 Ruochen Wang Jianjun Dong +3 位作者 Lishan Jin Yuyan Sun Taogetao Baoyin Xiumei Wang 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第2期387-411,共25页
Grassland biomass is an important parameter of grassland ecosystems.The complexity of the grassland canopy vegetation spectrum makes the long-term assessment of grassland growth a challenge.Few studies have explored t... Grassland biomass is an important parameter of grassland ecosystems.The complexity of the grassland canopy vegetation spectrum makes the long-term assessment of grassland growth a challenge.Few studies have explored the original spectral information of typical grasslands in Inner Mongolia and examined the influence of spectral information on aboveground biomass(AGB)estimation.In order to improve the accuracy of vegetation index inversion of grassland AGB,this study combined ground and Unmanned Aerial Vehicle(UAV)remote sensing technology and screened sensitive bands through ground hyperspectral data transformation and correlation analysis.The narrow band vegetation indices were calculated,and ground and airborne hyperspectral inversion models were established.Finally,the accuracy of the model was verified.The results showed that:(1)The vegetation indices constructed based on the ASD FieldSpec 4 and the UAV were significantly correlated with the dry and fresh weight of AGB.(2)The comparison between measured R^(2) with the prediction R^(2) indicated that the accuracy of the model was the best when using the Soil-Adjusted Vegetation Index(SAVI)as the independent variable in the analysis of AGB(fresh weight/dry weight)and four narrow-band vegetation indices.The SAVI vegetation index showed better applicability for biomass monitoring in typical grassland areas of Inner Mongolia.(3)The obtained ground and airborne hyperspectral data with the optimal vegetation index suggested that the dry weight of AGB has the best fitting effect with airborne hyperspectral data,where y=17.962e^(4.672x),the fitting R^(2) was 0.542,the prediction R^(2)was 0.424,and RMSE and REE were 57.03 and 0.65,respectively.Therefore,established vegetation indices by screening sensitive bands through hyperspectral feature analysis can significantly improve the inversion accuracy of typical grassland biomass in Inner Mongolia.Compared with ground monitoring,airborne hyperspectral monitoring better reflects the inversion of actual surface biomass.It provides a reliable modeling framework for grassland AGB monitoring and scientific and technological support for grazing management. 展开更多
关键词 Aboveground biomass inversion model vegetation index unmanned aerial vehicle typical grassland
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Analysis on Typical Spatio-temporal Characteristics of Open-cast Mining and Its Countermeasures
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作者 Qingyou AO Qiang FU +2 位作者 Zhihua LIU Yu XUN Lin LIN 《Asian Agricultural Research》 2024年第5期20-24,共5页
In order to deal with the special spatio-temporal environmental changes encountered in the process of open-cast mining,taking Huolinhe No.1 Open-cast Mine as the research object,this paper studied its typical problems... In order to deal with the special spatio-temporal environmental changes encountered in the process of open-cast mining,taking Huolinhe No.1 Open-cast Mine as the research object,this paper studied its typical problems in river reconstruction and cultural relics protection.The study focused on eight key core aspects,including the design optimization of the spatial layout of the mining area,the accurate estimation of the mineral resources reserves,the scientific theoretical demonstration of the mining scale,the fine analysis and calculation of the stripping ratio,the comprehensive consideration of the transport distance and efficiency,the accurate judgment of the best time for the implementation of the transformation,the analysis and evaluation of the slope stability,and the overall planning of the production system.The results show that the extracted problem-solving strategies and scheme system for special mining conditions can not only provide specific and practical guidance for Huolinhe No.1 Open-cast Mine,but also serve as a valuable reference and practical reference for other open-cast mine enterprises facing similar challenges. 展开更多
关键词 Open-cast mining in the mining area typical space-time environment River reconstruction Cultural relics protection Spatial layout
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Trade-off and Synergy of Rural Functions Under County Depopulation in the Typical Black Soil Region of Northeast China
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作者 LI Dongmei WEN Qing +1 位作者 QI Yue ZHANG Pingyu 《Chinese Geographical Science》 SCIE CSCD 2023年第4期616-633,共18页
As the population continues to shrink in the black soil region of Northeast China since 2000,it is critical to master the impact of population shrinkage on rural functions to realize rural revitalization and sustainab... As the population continues to shrink in the black soil region of Northeast China since 2000,it is critical to master the impact of population shrinkage on rural functions to realize rural revitalization and sustainable development.In this study,we focused on the impacts of depopulation on the evolution and interrelationship of rural subfunctions.Based on the rural function indexes system,the TOPSIS(Technique for Order Preference by Similarity to an Ideal Solution)method,spatial analysis method,and mathematical statistics analysis method were used to summarize the spatial and temporal characteristics of rural function development,as well as the effect of population shrinkage in the typical black soil region of Northeast China.The results showed that depopulation varied in the extent and duration between the forested region and plain areas,which both impacted the trajectories of rural subfunctions evolution.For the economic development function and ecological conservation function,the effect of continuous slight depopulation was beneficial,while the effect of rapid depopulation was adverse,which was exactly opposite to the agricultural production function.All forms of population shrinkage were conducive to the development of the social security function.With the deepening population shrinkage,depopulation mainly promoted the collaborative development between subfunctions in this study,except the relationship between agricultural production and social security function.But effects of depopulation on the interrelationship of rural subfunctions varied between the forested region and plain areas in some cases.The results provided evidence for the cognition that population shrinkage had complicated effects on rural subfunctions. 展开更多
关键词 rural function depopulation trade-off and synergy typical black soil region Northeast China
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A case of atypical neurological symptoms and high cerebro-spinal fluid acetone level due to transdermal exposure to isopropanol
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作者 Côme Fruit Sophie Guillotin +5 位作者 Marie Wolfrum Thomas Lanot Florent Battefort Pierre Girardie Marie Rafiq Nicolas Delcourt 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2023年第2期152-154,共3页
Dear editor, Isopropanol, also named 2-propanol or isopropyl alcohol(IPA), is a colorless, volatile liquid found in numerous household chemicals, such as cleaners and disinfectants, which typically contain a 70% solut... Dear editor, Isopropanol, also named 2-propanol or isopropyl alcohol(IPA), is a colorless, volatile liquid found in numerous household chemicals, such as cleaners and disinfectants, which typically contain a 70% solution of IPA in water. IPA is also extensively used in industry and laboratories as a solvent. 展开更多
关键词 ACETONE typically ALCOHOL
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Automatic Extraction of Typical River Vegetation Elements Based on Low-altitude Remote Sensing Images
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作者 Xiaomeng ZHANG Hao WU 《Meteorological and Environmental Research》 CAS 2023年第1期70-75,共6页
Based on low-altitude remote sensing images,this paper established sample set of typical river vegetation elements and proposed river vegetation extraction technical solution to adaptively extract typical vegetation e... Based on low-altitude remote sensing images,this paper established sample set of typical river vegetation elements and proposed river vegetation extraction technical solution to adaptively extract typical vegetation elements of river basins.The main research of this paper were as follows:(1)a typical vegetation extraction sample set based on low-altitude remote sensing images was established.(2)A low-altitude remote sensing image vegetation extraction model based on the focus perception module was designed to realize the end-to-end automatic extraction of different types of vegetation areas of low-altitude remote sensing images to fully learn the spectral spatial texture information and deep semantic information of the images.(3)By comparison with the baseline method,baseline method with embedded focus perception module showed an improvement in the precision by 7.37%and mIoU by 49.49%.Through visual interpretation and quantitative calculation analysis,the typical river vegetation adaptive extraction network has effectiveness and generalization ability,consistent with the needs of practical applications of vegetation extraction. 展开更多
关键词 altitude remote sensing images Deep learning Semantic segmentation typical river vegetation extraction Attention
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Is endoscopic resection a correct treatment for atypical gastrointestinal lipomas? 被引量:1
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作者 Edoardo Virgilio Paolo Mercantini Marco Cavallini 《World Journal of Clinical Cases》 SCIE 2016年第1期30-32,共3页
We would like offering our experience about a very rare and underestimated type of gastrointestinal lipoma,which is the lipoma with precancerous or frankly malignant features of the mucosal epithelium,the socalled aty... We would like offering our experience about a very rare and underestimated type of gastrointestinal lipoma,which is the lipoma with precancerous or frankly malignant features of the mucosal epithelium,the socalled atypical lipoma.So far,only few cases have been described in the world literature.Recently,we grappled with what we think the first case of atypical colonic lipoma presenting with adenocarcinomatous transformation of the overlying epithelium,as discussed in more detail below.We propose a new definition and classification for this kind of lesions and discuss about their diagnosis,treatment and prognosis. 展开更多
关键词 MALIGNANT epithelial transformation typical COLONIC LIPOMA Atypical COLONIC LIPOMA Oncologically MALIGNANT potential PREOPERATIVE endoscopy
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The Construal of Typical Hypallage Under the Hybrid Model
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作者 张洁 《疯狂英语(理论版)》 2016年第3期192-194,共3页
In this paper,the hybrid model based on the conceptual blending theory and qualia structure is applied to the interpretation of the meaning construction of typical hypallage.Based on this study,it has been proved that... In this paper,the hybrid model based on the conceptual blending theory and qualia structure is applied to the interpretation of the meaning construction of typical hypallage.Based on this study,it has been proved that the hypallage is not only a creative and appealing linguistic phenomenon but also a productive cognitive operation based on the double scope integration which enable people to use the same modifier to describe the things which intuitively belong to distinct sort of types without any cognitive difficulties. 展开更多
关键词 typical hypallage conceptual blending theory qualia structure
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Groundwater quality and land use change in a typical karst agricultural region:a case study of Xiaojiang watershed,Yunnan 被引量:14
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作者 JIANG Yongjun YUAN Daoxian +3 位作者 XIE Shiyou LI Linli ZHANG Gui HE Raosheng 《Journal of Geographical Sciences》 SCIE CSCD 2006年第4期405-414,共10页
Taking the typical karst agricultural region, Xiaojiang watershed in Luxi of Yurman Province as a research unit, utilizing the groundwater quality data in 1982 and 2004, the aerial photos in 1982 and TM images in 2004... Taking the typical karst agricultural region, Xiaojiang watershed in Luxi of Yurman Province as a research unit, utilizing the groundwater quality data in 1982 and 2004, the aerial photos in 1982 and TM images in 2004, supported by the GIS, we probe into the law and the reason of its space-time change of the groundwater quality over the past 22 years in the paper. The results show: (1) There were obvious temporal and spatial changes of groundwater quality during the past 22 years. (2) Concentrations of NH4^+, SO4^2- , NO3, NO2^-, Cl^- and the pH value, total hardness, total alkalinity increased significantly, in which NH4^2-, NO3, and NO2^- of groundwater exceeded the drinking water standards as a result of non-point pollution caused by the expansion of cultivated land and mass use of the fertilizer and pesticide. (3) Oppositely, Ca^2+ and HCO3^- showed an obvious decline trend due to forest reduction and degradation and stony desertification. Meantime, there was a dynamic relation between the groundwater quality change and the land use change. 展开更多
关键词 groundwater quality space-time change land use change typical karst agricultural region GIS Xiaojiang watershed
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Sulfur cycle in the typical meadow Calamagrostis angustifolia wetland ecosystem in the Sanjiang Plain,Northeast China 被引量:9
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作者 LIU Jingshuang LI Xinhua 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第4期470-475,共6页
The sulfur cycle and its compartmental distribution within an atmosphere-plant-soil system was studied using a compartment model in the typical meadow Calamagrostis angustifolia wetland in the Sanjiang Plain Northeast... The sulfur cycle and its compartmental distribution within an atmosphere-plant-soil system was studied using a compartment model in the typical meadow Calamagrostis angustifolia wetland in the Sanjiang Plain Northeast China. The results showed that in the typical meadow C. angustifolia wetland ecosystem, soil was the main storage compartment and current hinge of sulfur in which 98.4% sulfur was accumulated, while only 1.6% sulfur was accumulated in the plant compartment. In the plant subsystem, roots and litters were the main storage compartment of sulfur and they remained 83.5% of the total plant sulfur. The calculations of sulfur turnover through the compartments of the typical meadow C. angustifolia wetland ecosystem demonstrated that the above-ground component took up 0.99 gS/m^2 from the root, of which 0.16 gS/m^2 was translocated to the roots and 0.83 gS/m^2 to the litter. The roots took in 1.05 gS/m^2 from the soil, subsequent translocation back to the soil accounted for 1.31 gS/m^2, while there was 1.84 gS/m^2 in the litter and the net transfer of sulfur to the soil was more than 0.44 gS/(m^2·a). The emission of H2S from the typical meadow C. angustifolia wetland ecosystem to the atmosphere was 1.83 mgS/(m^2·a), while carbonyl sulfide (COS) was absorbed by the typical meadow C. angustifolia wetland ecosystem from the atmosphere at the rate of 1.76 mgS/(m^2·a). The input of sulfur by the rainfall to the ecosystem was 4.85 mgS/m^2 during the growing season. The difference between input and output was 4.78 mgS/m^2, which indicated that sulfur was accumulated in the ecosystem and may cause wetland acidify in the future. 展开更多
关键词 the Sanjiang Plain typical meadow Calamagrostis angustifolia wetland ECOSYSTEM sulfur cycle
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GJB2 mutation spectrum in deaf population in a typical southeastern area of China 被引量:10
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作者 DAI Pu YOU Yi-wen +5 位作者 CUI Jing-hong YU Fei HAN Bing KANG Dong-yang YUAN Hui-jun HAN Dong-yi 《Journal of Otology》 2006年第2期94-98,共5页
Mutations in GJB2 gene are the most frequently found mutations in patients with nonsyndromic hearing impairment. However, the spectrum and prevalence of mutations in this gene vary among different ethnic groups. In Ch... Mutations in GJB2 gene are the most frequently found mutations in patients with nonsyndromic hearing impairment. However, the spectrum and prevalence of mutations in this gene vary among different ethnic groups. In China, 30,000 infants are born with congenital hearing impairment annually. In order to provide appropriate genetic testing and counseling to the families, we investigated the molecular etiology of nonsyndromic deafness in 103 unrelated school children attending Nantong School for the Deaf and Mute in Jiangsu Province, China. The coding exon of the GJB2 gene was PCR amplified and sequenced. Sixty two GJB2 mutant alleles were identified in 35.9% (37/103) of the patients. Twenty five patients carried two pathogenic mutations and 12 patients carried one mutant allele. The 235delC was the most common mutation accounting for 69.4% (43/62) of GJB2 mutant alleles. The GJB2 mutant alleles accounted for 30.1% (62/206) of all chromosomes responsible for nonsyndromic hearing impairment. Testing of the 3 most prevalent deleterious frame shift mutations in this cohort detected 100% of all GJB2 mutant alleles. These results demonstrate that an effective genetic testing of GJB2 gene for patients and families with nonsyndromic hearing impairment is possible. 展开更多
关键词 GJB2 mutation spectrum in deaf population in a typical southeastern area of China GENE area
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Generation of typical operation curves for hydrogen storage applied to the wind power fluctuation smoothing mode 被引量:4
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作者 Yanhui Xu Yijia Xu Yan Huang 《Global Energy Interconnection》 EI CAS CSCD 2022年第4期353-361,共9页
In this paper,a typical-operation-curve generation method of a hydrogen energy storage system operating under the mode of stabilizing wind power fluctuations is proposed.This method is used to optimize the power and c... In this paper,a typical-operation-curve generation method of a hydrogen energy storage system operating under the mode of stabilizing wind power fluctuations is proposed.This method is used to optimize the power and capacity configuration of the energy storage system.The time series curves of the charging and discharging powers of the hydrogen energy storage are obtained by EMD decomposition,and the curves are classified according to the similarities and differences of the characteristic parameters in different time periods.After the classification,typical charging and discharging power values of each type of curve at each moment are obtained by a cloud model,and then,typical operation curves of each type are obtained by integration.On this basis,the power and capacity of the energy storage system are optimized with the objective of economic optimization through the MATLAB CPLEX toolbox.Combined with the measured data of a wind farm with an installed capacity of 400 MW in Northeast China,the validity and rationality of the typical operation curve generation method proposed in this paper are verified. 展开更多
关键词 Wind farm Hydrogen energy storage system Cluster analysis typical operation curves Capacity configuration
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High Performance Concrete and Its Typical Mixes 被引量:3
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作者 Cai Yuebo , Kwan Kwokhung , Cheung Yaukai Chan Honchuen Senior Engineer, Material and Structure Department, Nanjing Hydraulic Research Institute, Nanjing 210024 P. H. Doctor, Department of Civil and Structural Engineering, University of Hong Kong Professor, Department of Civil and Structural Engineering, University of Hong Kong 《China Ocean Engineering》 SCIE EI 1995年第3期335-344,共10页
With the modern development of chemical and mineral admixtures, it is now possible to produce much higher performance concrete than before. Higher performance does not only mean higher strength, but also better durabi... With the modern development of chemical and mineral admixtures, it is now possible to produce much higher performance concrete than before. Higher performance does not only mean higher strength, but also better durability, lower risk of thermal cracking and higher dimensional stability etc. The three most effective admixtures for producing high performance concrete are superplastieizer, pulverized fuel ash and condensed silica fume. This paper outlines the properties of these materials and presents some practical guidelines for their usage. 展开更多
关键词 high performance concrete SUPERPLASTICIZER pulverized fuel ash condensed silica fume typical mixes
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An Improved Method for Generating Typical Meteorological Years Used in Building Energy Simulation in China 被引量:2
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作者 Qiu-Hua Tao Zheng-Rong Li +2 位作者 Fu-Jian Jiang Yuan Lu Ling-Zhou Hu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第1期17-24,共8页
The present study proposes an improved method for generating better typical meteorological years( TMYs) used in building energy simulation in China. Modifications are made to the commonly used Sandia method,by optimiz... The present study proposes an improved method for generating better typical meteorological years( TMYs) used in building energy simulation in China. Modifications are made to the commonly used Sandia method,by optimizing the weightings of indices and thus giving more emphasis to dry bulb temperature and relative humidity and less to wind velocity. After analyzing the solar heat gain on the vertical envelop,an index of diffuse radiation rather than direct normal radiation is added for solar radiation. Using the improved method proposed,TMYs for 5 representative cities of 5 major climate zones in China are generated from the meteorological data recorded during the period 1981—2010. The results show that,compared with previous studies,the monthly diffuse solar radiation of typical meteorological months generated by the improved method are the"closest"to the 30-year average,and the comparison between annual diffuse radiation for the TMY and the 30-year annual average is improved,while little adverse effect is produced on global horizontal radiation comparisons,indicating that the improved method is more suitable to generate the TMY data than previous studies. 展开更多
关键词 typical METEOROLOGICAL YEAR improved method weighting MODIFICATION DIFFUSE solar radiation
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Wind power time series simulation model based on typical daily output processes and Markov algorithm 被引量:2
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作者 Zhihui Cong Yuecong Yu +1 位作者 Linyan Li Jie Yan 《Global Energy Interconnection》 EI CAS CSCD 2022年第1期44-54,共11页
The simulation of wind power time series is a key process in renewable power allocation planning,operation mode calculation,and safety assessment.Traditional single-point modeling methods discretely generate wind powe... The simulation of wind power time series is a key process in renewable power allocation planning,operation mode calculation,and safety assessment.Traditional single-point modeling methods discretely generate wind power at each moment;however,they ignore the daily output characteristics and are unable to consider both modeling accuracy and efficiency.To resolve this problem,a wind power time series simulation model based on typical daily output processes and Markov algorithm is proposed.First,a typical daily output process classification method based on time series similarity and modified K-means clustering algorithm is presented.Second,considering the typical daily output processes as status variables,a wind power time series simulation model based on Markov algorithm is constructed.Finally,a case is analyzed based on the measured data of a wind farm in China.The proposed model is then compared with traditional methods to verify its effectiveness and applicability.The comparison results indicate that the statistical characteristics,probability distributions,and autocorrelation characteristics of the wind power time series generated by the proposed model are better than those of the traditional methods.Moreover,modeling efficiency considerably improves. 展开更多
关键词 Wind power Time series typical daily output processes Markov algorithm Modified K-means clustering algorithm
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VOR and CVOR Index for Health Evaluation of Typical Steppe in Inner Mongolia 被引量:2
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作者 SHAN Gui-lian JIANG Hua +4 位作者 YAN Wei-hong Liu Zhong-ling LUO Fu-cheng DUAN Xin-hui CHU Xiao-hui 《Animal Husbandry and Feed Science》 CAS 2012年第6期266-270,共5页
[Objective] The aim of this study was to evaluate the effect of livestock exclusion on the health of grassland ecosystem accurately and quantitatively. [Method] One open grazing site and five seasonal exclusion sites,... [Objective] The aim of this study was to evaluate the effect of livestock exclusion on the health of grassland ecosystem accurately and quantitatively. [Method] One open grazing site and five seasonal exclusion sites, which had the same vegetation composition (taking Leymus chinensis and Stipa krylovii as main species) and soil type, were chosen as research objects for the VOR and CVOR evaluation of the effect of open grazing and livestock exclusion on the health of typical steppes, and for building the calculation model for VOR and CVOR indices to evaluate the health of typical steppes with different exclusion periods. [ Result] The VOR and CVOR composite indices both could accurately evaluate the health of typical steppes, and the evaluation results from the both indices were quite consistent. Although the condition (C), vigor(V), organization (O) and resilience( R ) indices changed differently in different exclusion periods, the VOR and CVOR composite indices increased gradually with the peri- od of exclusion prolonged, and the health condition of typical steppe changed from "alert" level (in the open grazing and earlier exclusion period) to "healthy" level (after 13 to 20 years'exclusion). [ Conclusion] The application of exclusion was beneficial to the recovery of degraded grassland ecosystem. 展开更多
关键词 typical steppe Health evaluation GRAZING Seasonal exclusion VOR index CVOR index
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Recommended Concentration Limits of Typical Indoor Air Contaminants 被引量:1
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作者 LV Chao1,JIANG Yun-tao2,ZHAO Jia-ning1(1.School of Municipal & Environmental Engineering,Harbin Institute of Technology,Harbin,Heilongjiang 150090,China 2.The Architectural Design and Research Institute,Harbin Institute of Technology,Harbin,Heilongjiang 150090,China) 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第S1期60-65,共6页
From the view of both objective and subjective factors,the indoor air quality(IAQ)evaluation was considered.Carbon dioxide(CO2)and formaldehyde(HCHO)were selected as the typical contaminants of indoor air,and the eval... From the view of both objective and subjective factors,the indoor air quality(IAQ)evaluation was considered.Carbon dioxide(CO2)and formaldehyde(HCHO)were selected as the typical contaminants of indoor air,and the evaluation method of logarithmic index was adopted as the evaluation means of IAQ.Then the recommended limits(RL)of typical contaminants CO2 and HCHO were given through analysis and calculation.The limits of CO2 and HCHO in Indoor Air Quality Standard of China or other existing standards probably correspond to the level of PD=25(%).The result shows that the existing standards fail to meet the requirement of the definition of "acceptable indoor air quality",that is to say,less than 20% of the people express dissatisfaction.When PD=20%,RL of CO2 and HCHO are 728×10-6 and 0.068×10-6 respectively,which are stricter than the limits in the existing standards.The method proposed in this paper is applicable to 13.1%≤PD≤86.7%. 展开更多
关键词 INDOOR air quality(IAQ) typical CONTAMINANTS recommended limits(RL) evaluation method of logarithmic index PERCENTAGE of dissatisfaction(PD)
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Differential diagnosis of tachycardia with a typical left bundle branch block morphology 被引量:1
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作者 Jeffrey S Neiger Richard G Trohman 《World Journal of Cardiology》 CAS 2011年第5期127-134,共8页
The evaluation of wide QRS complex tachycardias (WCT)remains a common dilemma for clinicians.Numerous algorithms exist to aid in arriving at the correct diagnosis.Unfortunately,these algorithms are difficult to rememb... The evaluation of wide QRS complex tachycardias (WCT)remains a common dilemma for clinicians.Numerous algorithms exist to aid in arriving at the correct diagnosis.Unfortunately,these algorithms are difficult to remember,and overreliance on them may prevent cardiologists from understanding the mechanisms underlying these arrhythmias.One distinct subcategory of WCTs are those that present with a"typical"or"classic" left bundle branch block pattern.These tachycardias may be supraventricular or ventricular in origin and arise from functional or fixed aberrancy,bystander or participating atriofascicular pre-excitation,and bundle branch reentry.This review will describe these arrhythmias,illustrate their mechanisms,and discuss their clinical features and treatment strategies. 展开更多
关键词 typical left BUNDLE branch block Wide complex TACHYCARDIA BUNDLE branch REENTRANT VENTRICULAR TACHYCARDIA
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Long-term grazing exclusion influences arbuscular mycorrhizal fungi and their association with vegetation in typical steppe of Inner Mongolia,China 被引量:1
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作者 CHEN Xue-jiao LIN Qi-mei +4 位作者 ZHAO Xiao-rong CHEN Hao WEN Jing LI Ying LI Gui-tong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第6期1445-1453,共9页
It is not certain that long-term grazing exclusion influences arbuscular mycorrhizal (AM) fungi and their association with steppe vegetation. In this study, soil and plant samples were collected from two sites of gr... It is not certain that long-term grazing exclusion influences arbuscular mycorrhizal (AM) fungi and their association with steppe vegetation. In this study, soil and plant samples were collected from two sites of grazing exclusion since 1983 (E83) and 1996 (E96), and one site of free-grazing (FG) in the typical steppe of Xilinguole League, Inner Mongolia, China, and assayed for soil basic physicochemical properties, AM fungal parameters, aboveground biomass and shoot phosphorus (P) uptake as well. The results showed that long-term grazing exclusion of E83 and E96 led to less drastic seasonal changes and significant increases in spore density, hyphal length density and root colonization intensity of AM fungi and even soil alkaline phosphatase activity, by up to 300, 168, 110 and 102%, respectively, compared with those of FG site. In addition, the total aboveground biomass and shoot P uptake of E83 and E96 were 75-992% and 58-645%, respectively, higher than those of FG. Generally, the root colonization intensity, spore density, and hyphal length density of AM fungi were all positively correlated with the aboveground biomass and even shoot P uptake of plant. These results may imply that grazing exclusion play a critical role in increasing the growth of AM fungi, and subsequently, may increase plant P uptake and aboveground biomass production. Moreover, the spore density could sensitively reflect the impacts of long-term grazing exclusion on AM fungi since survival strategy of spores in soil. 展开更多
关键词 typical steppe long-term grazing exclusion arbuscular mycorrhizal fungi aboveground biomass shoot phosphorus uptake
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Regions and Their Typical Paradigms for Soil and Water Conservation in China 被引量:1
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作者 DANG Xiaohu SUI Boyang +5 位作者 GAO Siwen LIU Guobin WANG Tao WANG Bing NING Duihu BI Wei 《Chinese Geographical Science》 SCIE CSCD 2020年第4期643-664,共22页
China is experiencing conflicts between its large population and scarce arable land,and between a demand for high productivity and the severe soil erosion of arable land.Since 1949,China has committed to soil and wate... China is experiencing conflicts between its large population and scarce arable land,and between a demand for high productivity and the severe soil erosion of arable land.Since 1949,China has committed to soil and water conservation(SWC),for which eight regions and 41 subregions have been developed to improve the environment and increase land productivity.To obtain information from the regional planning and strategies for SWC and to explore whether SWC practices simultaneously contribute to soil conservation,ecosystem functioning,and the livelihoods of local farmers,and to summarize the successful experiences of various SWC paradigms with distinct characteristics and mechanisms of soil erosion,this paper systematically presents seven SWC regions(excluding the Tibetan Plateau region)and 14 typical SWC paradigms,focusing on erosion mechanisms and the key challenges or issues in the seven regions as well as on the core problems,main objectives,key technologies,and the performance of the 14 typical paradigms.In summary,the 14 typical SWC paradigms successfully prevent and control local soil erosion,and have largely enhanced,or at least do not harm,the livelihoods of local farmers.However,there remain many challenges and issues on SWC and socioeconomic development that need to be addressed in the seven SWC regions.China,thus,still has a long way to go in successfully gaining the win-win objective of SWC and human aspects of development. 展开更多
关键词 regions for soil and water conservation soil erosion dryland farming collapse erosion karst rocky desertification typical paradigm for soil and water conservation
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Movement and variation of four typical glaciers in the Qilian Mountains,northwestern China 被引量:1
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作者 ZheFan Jing Kun Wang Li Liu 《Research in Cold and Arid Regions》 CSCD 2015年第3期206-211,共6页
We selected four typical glaciers in the Qilian Mountains and investigated their movements and variation using advanced technologies such as remote sensing, photographic measurements, and global positioning systems. T... We selected four typical glaciers in the Qilian Mountains and investigated their movements and variation using advanced technologies such as remote sensing, photographic measurements, and global positioning systems. The velocity of glacier movements in the Qilian Mountains is relatively low, and there has been no significant variation during the past 50 years. Glacier motion has maintained a normal style. The movement velocity of Laohugou Glacier No. 12 presented a decreasing trend (by 48%) from 1960 to 2012. The movement velocity of the Qiyi Glacier also presented a decreasing trend (by 48.1%) from 1958 to 2012; it decreased by 29.4% from 1958 to 1977 and by 26.5% from 1977 to 2012. Therefore, the Qiyi Glacier's movement velocity varied greatly over the earlier 20 years (1958 1977), but presented a small decreasing trend during the latter 30 years (1977-2012). By comparing the movement velocity variation of these typical glaciers, we determined that the extent of variation was consistent among large glaciers (such as Laohugou Glacier No. 12) and small glaciers (such as the Qiyi Glacier and Yanglonghe Glacier No. 5), despite their different sizes. 展开更多
关键词 typical glaciers movement velocity VARIATION extent Qilian Mountains
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