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A phenology-based vegetation index for improving ratoon rice mapping using harmonized Landsat and Sentinel-2 data 被引量:2
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作者 Yunping Chen Jie Hu +6 位作者 Zhiwen Cai Jingya Yang Wei Zhou Qiong Hu Cong Wang Liangzhi You Baodong Xu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1164-1178,共15页
Ratoon rice,which refers to a second harvest of rice obtained from the regenerated tillers originating from the stubble of the first harvested crop,plays an important role in both food security and agroecology while r... Ratoon rice,which refers to a second harvest of rice obtained from the regenerated tillers originating from the stubble of the first harvested crop,plays an important role in both food security and agroecology while requiring minimal agricultural inputs.However,accurately identifying ratoon rice crops is challenging due to the similarity of its spectral features with other rice cropping systems(e.g.,double rice).Moreover,images with a high spatiotemporal resolution are essential since ratoon rice is generally cultivated in fragmented croplands within regions that frequently exhibit cloudy and rainy weather.In this study,taking Qichun County in Hubei Province,China as an example,we developed a new phenology-based ratoon rice vegetation index(PRVI)for the purpose of ratoon rice mapping at a 30 m spatial resolution using a robust time series generated from Harmonized Landsat and Sentinel-2(HLS)images.The PRVI that incorporated the red,near-infrared,and shortwave infrared 1 bands was developed based on the analysis of spectro-phenological separability and feature selection.Based on actual field samples,the performance of the PRVI for ratoon rice mapping was carefully evaluated by comparing it to several vegetation indices,including normalized difference vegetation index(NDVI),enhanced vegetation index(EVI)and land surface water index(LSWI).The results suggested that the PRVI could sufficiently capture the specific characteristics of ratoon rice,leading to a favorable separability between ratoon rice and other land cover types.Furthermore,the PRVI showed the best performance for identifying ratoon rice in the phenological phases characterized by grain filling and harvesting to tillering of the ratoon crop(GHS-TS2),indicating that only several images are required to obtain an accurate ratoon rice map.Finally,the PRVI performed better than NDVI,EVI,LSWI and their combination at the GHS-TS2 stages,with producer's accuracy and user's accuracy of 92.22 and 89.30%,respectively.These results demonstrate that the proposed PRVI based on HLS data can effectively identify ratoon rice in fragmented croplands at crucial phenological stages,which is promising for identifying the earliest timing of ratoon rice planting and can provide a fundamental dataset for crop management activities. 展开更多
关键词 ratoon rice phenology-based ratoon rice vegetation index(PRVI) phenological phase feature selection Harmonized Landsat Sentinel-2 data
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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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Coagulation indices and fibrinogen degradation products as predictive biomarkers for tumor-node-metastasis staging and metastasis in gastric cancer
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作者 Yi-Qing Shen Qiu-Wan Wei +2 位作者 Yi-Ren Tian Yun-Zhi Ling Min Zhang 《World Journal of Gastrointestinal Oncology》 SCIE 2025年第1期110-120,共11页
BACKGROUND Gastric cancer(GC)is a prevalent malignancy with a substantial health burden and high mortality rate,despite advances in prevention,early detection,and treatment.Compared with the global average,Asia,notabl... BACKGROUND Gastric cancer(GC)is a prevalent malignancy with a substantial health burden and high mortality rate,despite advances in prevention,early detection,and treatment.Compared with the global average,Asia,notably China,reports disproportionately high GC incidences.The disease often progresses asymptoma-tically in the early stages,leading to delayed diagnosis and compromised out-comes.Thus,it is crucial to identify early diagnostic biomarkers and enhance treatment strategies to improve patient outcomes and reduce mortality.METHODS Retrospectively analyzed the clinical data of 148 patients with GC treated at the Civil Aviation Shanghai Hospital between December 2022 and December 2023.The associations of coagulation indices-partial thromboplastin time(APTT),prothrombin time(PT),thrombin time(TT),fibrinogen,fibrinogen degradation products(FDP),fasting blood glucose,and D-dimer(D-D)with TNM stage and distant metastasis were examined.RESULTS Prolongation of APTT,PT,and TT was significantly correlated with the GC TNM stage.Hence,abnormal coagulation system activation was closely related to disease progression.Elevated FDP and D-D were significantly associated with distant metastasis in GC(P<0.05),suggesting that increased fibrinolytic activity contributes to increased metastatic risk.CONCLUSION Our Results reveal coagulation indices,FDPs as GC biomarkers,reflecting abnormal coagulation/fibrinolysis,aiding disease progression,metastasis prediction,and helping clinicians assess thrombotic risk for early intervention and personalized treatment plans. 展开更多
关键词 Coagulation indexes Fibrinogen degradation products Gastric cancer Tumor-node-metastasis staging Distant metastasis
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Establishment of Monitoring and Assessment Index System of Land Degradation of Farmland Ecosystems at Small-scale
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作者 高亚琪 杨艺渊 +1 位作者 地力夏提.包尔汉 朱雅丽 《Agricultural Science & Technology》 CAS 2015年第7期1505-1507,1561,共4页
The research established land degradation monitoring and assessment in- dex system of farmland ecosystem under influence of human activities, including farming system, measures, mulch residuals, fertilizer pollutions,... The research established land degradation monitoring and assessment in- dex system of farmland ecosystem under influence of human activities, including farming system, measures, mulch residuals, fertilizer pollutions, pesticide pollution, irrigation method, salt content of soils, engineering measures of discharging alkali, agricultural protection forests and poverty. The indices of the system are accessible, and convenient for operation, which is suitable for land managers self-monitoring, re- ducing irrational farming activities, improving farmland productivity and preventing farmland degradation. 展开更多
关键词 FARMLAND Land degradation MONITORING ASSESSMENT index system
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index.dat文件结构解析 被引量:8
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作者 吴清 吴顺祥 《现代计算机》 2008年第12期4-7,共4页
在Windows操作系统中,index.dat文件是一个由IE浏览器和资源管理器创建的文件。通过对文件结构的分析研究,从二进制流数据中提取出用户个人信息,并编写程序进行验证。结果表明对文件结构理解的正确性,以及该解析过程在计算机取证中的应用。
关键词 计算机取证 index.dat 文件解析
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Cache-Conscious Index Mechanism for Main-Memory Databases 被引量:5
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作者 SUN Li-mei SONG Bao-yan YU Ya-xin LI Fang-fang YU Ge 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第1期309-312,共4页
Recent studies have addressed that the cache be havior is important in the design of main memory index structures. Cache-conscious indices such as the CSB^+-tree are shown to outperform conventional main memory indic... Recent studies have addressed that the cache be havior is important in the design of main memory index structures. Cache-conscious indices such as the CSB^+-tree are shown to outperform conventional main memory indices such as the AVL-tree and the T-tree. This paper proposes a cacheconscious version of the T-tree, CST-tree, defined according to the cache-conscious definition. To separate the keys within a node into two parts, the CST-tree can gain higher cache hit ratio. 展开更多
关键词 index structure main memory database real time application cache-conscious T-tree indexing CST-tree indexing
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Physical activity, physical fitness, and body mass index in the Chinese child and adolescent populations: An update from the 2016 Physical Activity and Fitness in China The Youth Study 被引量:34
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作者 Peijie Chen 《Journal of Sport and Health Science》 SCIE 2017年第4期381-383,共3页
In this special issue of the Journal of Sport and Health Science, analyses of the most recent national prevalence esti- mates from the 2016 Physical Activity and Fimess in China-- The Youth Study (PAFCTYS) are prese... In this special issue of the Journal of Sport and Health Science, analyses of the most recent national prevalence esti- mates from the 2016 Physical Activity and Fimess in China-- The Youth Study (PAFCTYS) are presented. These include the prevalence of moderate-to-vigorous physical activity (MVPA). 展开更多
关键词 Physical activity physical fitness body mass index
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Comparison of marine controlled-source electromagnetic data acquisition systems by a reservoir sensitivity index:analyzing the effect of water depths 被引量:9
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作者 GUO Zhenwei DONG Hefeng LIU Jianxin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第11期113-119,共7页
During the past ten years, a marine controlled source electromagnetic(CSEM) method has been developed rapidly as a technology for hydrocarbon exploration. For shallow water environments, two CSEM data acquisition sy... During the past ten years, a marine controlled source electromagnetic(CSEM) method has been developed rapidly as a technology for hydrocarbon exploration. For shallow water environments, two CSEM data acquisition systems: Seabed Logging(SBL) and towed streamer electromagnetics(TSEM) have been developed in recent years. The purpose is to compare the performance of the SBL and TSEM systems at different water depths. Three different methods for the comparison are presented. The first method is a quick one dimensional sensitivity modelling. As a result, the sensitivity of marine CSEM data increases with water depth for the SBL system. Further, the sensitivity decreases with the increasing water depth for the TSEM system. The two other methods use two dimensional synthetic data from a simple 2-D isotropic model. The second method is a reservoir sensitivity index(RSI) method which has been developed to provide a quick comparison of the two systems. The RSI is calculated as the amplitude of the scattered field dividing by data uncertainty. From the calculations, it is found that with the increasing water depth RSI increases for the SBL system, while it decreases for the TSEM system. The third method uses Occam's inversion, and applies an anomaly transverse resistance(ATR) ratio for evaluating the resulting resistivity image. In shallow water environments, the resolution of the CSEM inversion results is good for both the SBL and TSEM systems. In deep water environments, the resolution of the CSEM inversion is better for the SBL system than for the TSEM system. The ATR ratios of the resistivity images show the similar conclusion. The SBL data acquisition system has an advantage in deep water environments. The TSEM system, on the other hand, is preferable for the shallow water environments. 展开更多
关键词 controlled-source electromagnetic reservoir sensitivity index seabed logging towed streamerelectromagnetic
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Validation of nutritional risk index method against patientgenerated subjective global assessment in screening malnutrition in colorectal cancer patients 被引量:25
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作者 Elnaz Faramarzi Reza Mahdavi +1 位作者 Mohammad Mohammad-Zadeh Behnam Nasirimotlagh 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2013年第5期544-548,共5页
Objective:To validate malnutrition screening tool of nutrition risk index (NRI) against patent-generated subjective global assessment (PG-SGA) as a gold standard tool in colorectal cancer patients before radiothe... Objective:To validate malnutrition screening tool of nutrition risk index (NRI) against patent-generated subjective global assessment (PG-SGA) as a gold standard tool in colorectal cancer patients before radiotherapy.Methods:Nutritional status of 52 volunteer colorectal cancer patients with a mean age of 54.1±16.8 years who referred to radiotherapy center were assessed by PG-SGA (gold standard method) and NRI.Serum albumin levels of patients were determined by colorimetric method.A contingency table was used to determine the sensitivity,specificity,and predictive value of the NRI in screening patients at risk of malnutrition,in comparison with the PG-SGA in patients before radiotherapy.Results:The findings of PG-SGA and NRI showed that 52% and 45% of patients in our study were moderately or severely malnourished respectively.The NRI had a sensitivity of 66% and a specificity of 60% against PG-SGA.The positive predictive value was 64% and the negative predicative value was 62%.The agreement between NRI and PG-SGA was statistically insignificant (kappa =0.267; P>0.05).Conclusions:The findings of present study showed that the prevalence of malnutrition was high in patients with colorectal cancer.Moreover,NRI method had low sensitivity and specificity in assessing nutritional status of patients with cancer.It seems that the combination of anthropometric,laboratory parameters and a subjective scoring system may be helpful tools in screening of malnutrition in cancer patients. 展开更多
关键词 Colorectal cancer patients MALNUTRITION patient-generated subjective global assessment nutrition risk index (NRI)
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Comparative analysis of GF-1,HJ-1,and Landsat-8 data for estimating the leaf area index of winter wheat 被引量:16
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作者 LI He CHEN Zhong-xin +4 位作者 JIANG Zhi-wei WU Wen-bin REN Jian-qiang LIU Bin Tuya Hasi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第2期266-285,共20页
Using simultaneously collected remote sensing data and field measurements, this study firstly assessed the consistency and applicability of China high-resolution earth observation system satellite 1 (GF-1) wide fiel... Using simultaneously collected remote sensing data and field measurements, this study firstly assessed the consistency and applicability of China high-resolution earth observation system satellite 1 (GF-1) wide field of view (WFV) camera, environment and disaster monitoring and forecasting satellite (H J-l) charge coupled device (CCD), and Landsat-8 opera- tional land imager (OLI) data for estimating the leaf area index (LAI) of winter wheat via reflectance and vegetation indices (VIs). The accuracies of these LAI estimates were then assessed through comparison with an empirical model and the PROSAIL radiative transfer model. The effects of radiation calibration, spectral response functions, and spatial resolution on discrepancies in the LAI estimates between the different sensors were also analyzed. The results yielded the following observations: (1) The correlation between reflectance from different sensors is relative good, with the adjusted coefficients of determination (R2) between 0.375 to 0.818. The differences in reflectance are ranging from 0.002 to 0.054. The correlation between VIs from different sensors is high with the R2 between 0.729 and 0.933. The differences in the VIs are ranging from 0.07 to 0.156. These results show the three sensors' images can all be used for cross calibration of the reflectance and VIs. (2) The four VIs from the three sensors are all demonstrated to be highly correlated with LAI (R2 between 0.703 and 0.849). The linear models associated with the 2-band enhanced vegetation index (EVI2), which feature the highest R2 (higher than 0.746) and the lowest root mean square errors (RMSE) (less than 0.21), were selected to estimate the winter wheat LAI. The accuracy of the estimated LAI from Landsat-8 was the highest, with the relative errors (RE) of 2.18% and an RMSE of 0.13, while the H J-1 was the lowest, with the RE of 2.43% and the RMSE of 0.15. (3) The inversion errors in the different sensors' LAI estimates using the PROSAIL model are small. The accuracy of the GF-1 is the highest with the RE of 3.44%, and the RMSE of 0.22, whereas that of the H J-1 is the lowest with the RE of 4.95%, and the RMSE of 0.26. (4) The effects of the spectral response function and radiation calibration for the different sensors are small and can be ignored, but the effects of spatial resolution are significant and must be taken into consideration in practical applications. 展开更多
关键词 GF-1 WFV H J-1 CCD Landsat-80LI leaf area index PROSAIL vegetation indices
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Novel association between sperm deformity index and oxidative stress-induced DNA damage in infertile male patients 被引量:10
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作者 Tamer M.Said Nabil Aziz +3 位作者 Rakesh K.Sharma Iwan Lewis-Jones AnthonyJ.ThomasJr AshokAgarwal 《Asian Journal of Andrology》 SCIE CAS CSCD 2005年第2期121-126, ,共6页
Aim:To investigate the impact of abnormal sperm morphology using the sperm deformity index (SDI) on reactive oxygen species (ROS) production and its correlation with sperm DNA damage.Methods:Semen samples were collect... Aim:To investigate the impact of abnormal sperm morphology using the sperm deformity index (SDI) on reactive oxygen species (ROS) production and its correlation with sperm DNA damage.Methods:Semen samples were collected from men undergoing infertility screening (n=7) and healthy donors (n=6).Mature spermatozoa were isolated and incubated with 5 mmol/L β-nicotinamide adenine dinucleotide phosphate (NADPH) for up to 24 h to induce ROS.Sperm morphology was evaluated using strict Tygerberg's criteria and the SDI.ROS levels and DNA damage were assessed using chemiluminescence and terminal deoxynucleotidyl transferase-mediated fluorescein- dUTP nick end labeling (TUNEL) assays,respectively.Results:SDI values (median [interquartiles]) were higher in patients than donors (2 [1.8,2.1] vs.1.53 [1.52,1.58],P=0.008).Aliquots treated with NADPH showed higher ROS levels (1.22 [0.30,1.87] vs.0.39 [0.10,0.57],P=0.03) and higher incidence of DNA damage than those not treated (10 [4.69,24.85] vs.3.85 [2.58,5.10],P=0.008).Higher DNA damage was also seen following 24 h of incubation in patients compared to donors.SDI correlated with the percentage increase in sperm DNA damage following incubation for 24 h in samples treated with NADPH (r=0.7,P=0.008) and controls (r=0.58,P=0.04). Conclusion:SDI may be a useful tool in identifying potential infertile males with abnormal prevalence of oxidative stress (OS)-induced DNA damage.NADPH plays a role in ROS-mediated sperm DNA damage,which appears to be more evident in infertile patients with semen samples containing a high incidence of morphologically abnormal spermatozoa. 展开更多
关键词 β-nicotinamide adenine dinucleotide phosphate oxidative stress sperm deformity index sperm DNA damage
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An entirely new approach based on remote sensing data to calculate the nitrogen nutrition index of winter wheat 被引量:7
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作者 ZHAO Yu WANG Jian-wen +5 位作者 CHEN Li-ping FU Yuan-yuan ZHU Hong-chun FENG Hai-kuan XU Xin-gang LI Zhen-hai 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第9期2535-2551,共17页
The nitrogen nutrition index(NNI)is a reliable indicator for diagnosing crop nitrogen(N)status.However,there is currently no specific vegetation index for the NNI inversion across multiple growth periods.To overcome t... The nitrogen nutrition index(NNI)is a reliable indicator for diagnosing crop nitrogen(N)status.However,there is currently no specific vegetation index for the NNI inversion across multiple growth periods.To overcome the limitations of the traditional direct NNI inversion method(NNI_(T1))of the vegetation index and traditional indirect NNI inversion method(NNI_(T2))by inverting intermediate variables including the aboveground dry biomass(AGB)and plant N concentration(PNC),this study proposed a new NNI remote sensing index(NNI_(RS)).A remote-sensing-based critical N dilution curve(Nc_(_RS))was set up directly from two vegetation indices and then used to calculate NNI_(RS).Field data including AGB,PNC,and canopy hyperspectral data were collected over four growing seasons(2012–2013(Exp.1),2013–2014(Exp.2),2014–2015(Exp.3),2015–2016(Exp.4))in Beijing,China.All experimental datasets were cross-validated to each of the NNI models(NNI_(T1),NNI_(T2)and NNI_(RS)).The results showed that:(1)the NNI_(RS)models were represented by the standardized leaf area index determining index(sLAIDI)and the red-edge chlorophyll index(CI_(red edge))in the form of NNI_(RS)=CI_(red edge)/(a×sLAIDI~b),where"a"equals 2.06,2.10,2.08 and 2.02 and"b"equals 0.66,0.73,0.67 and 0.62 when the modeling set data came from Exp.1/2/4,Exp.1/2/3,Exp.1/3/4,and Exp.2/3/4,respectively;(2)the NNI_(RS)models achieved better performance than the other two NNI revised methods,and the ranges of R2 and RMSE were 0.50–0.82 and 0.12–0.14,respectively;(3)when the remaining data were used for verification,the NNI_(RS)models also showed good stability,with RMSE values of 0.09,0.18,0.13 and 0.10,respectively.Therefore,it is concluded that the NNI_(RS)method is promising for the remote assessment of crop N status. 展开更多
关键词 nitrogen nutrition index(NNI) critical nitrogen dilution curve standardized leaf area index determining index(s LAIDI) the red-edge chlorophyll index(CI_(red edge))
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A soil quality index for evaluation of degradation under land use and soil erosion categories in a small mountainous catchment, Iran 被引量:2
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作者 Kazem NOSRATI Adrian LCOLLINS 《Journal of Mountain Science》 SCIE CSCD 2019年第11期2577-2590,共14页
Soil erosion and land use type have long been viewed as being particularly important drivers of soil degradation.The objectives of this study,therefore,were to select a new soil quality index(SQI)which varies signific... Soil erosion and land use type have long been viewed as being particularly important drivers of soil degradation.The objectives of this study,therefore,were to select a new soil quality index(SQI)which varies significantly with land use/soil erosion,and to evaluate the new SQI using expert opinion.In total,18 soil physical,chemical,and biochemical properties(indicators)were measured on 56 soil samples collected from four land use/soil erosion categories(rangeland/surface erosion,rangeland/subsurface erosion,cultivated land/surface erosion and dry-farming land/surface erosion).Principal component and classification analysis(PCCA)identified five PCs that explained 77.7%of the variation in soil properties with the biochemical PC varying significantly with land use/soil erosion.General discriminant analysis(GDA)selected urease and clay as the most sensitive properties distinguishing the land use/soil erosion categories.The GDA canonical scores for the new SQI were significantly correlated with expert opinion soil surface summed scores(for soil movement,surface litter,pedestalling,rills and flow pattern)derived using the U.S.Department of the Interior Bureau of Land Management(BLM)method.A forward stepwise general regression model revealed that the new SQI values were explained by soil movement,surface litter,and the summed values of the soil surface factors.Overall,this study confirmed that soil quality in the study area in Iran is controlled by land use and corresponding soil erosion. 展开更多
关键词 SOIL quality index Land use Erosion status SOIL ENZYME activities MULTIVARIATE statistical techniques
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Translation and validation of the Nepean Dyspepsia Index for functional dyspepsia in China 被引量:11
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作者 Xiao-Ping Tian Ying Li +6 位作者 Fan-Rong Liang Guo-Jie Sun Jie Yan Xiao-Rong Chang Ting-Ting Ma Shu-Yuan Yu Xu-Guang Yang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第25期3173-3177,共5页
AIM: To assess the reliability and validity of the translated version of Nepean Dyspepsia Index (NDI) in Chinese patients with documented functional dyspepsia (FO). METHODS: The translation process included forw... AIM: To assess the reliability and validity of the translated version of Nepean Dyspepsia Index (NDI) in Chinese patients with documented functional dyspepsia (FO). METHODS: The translation process included forward translation, back translation, pretest and cross-cultural adaptation. Reliability and validity of the translated version were examined by asking 300 subjects to complete the Chinese version of the NDI. The mean age of subjects was 39.24 years and 68.7% of the subjects were women. Internal consistency analysis with Cronbach's α was performed to test the reliability. Correlation analysis was used to assess the content validity. Factor analysis and structural equation models were used to assess the construct validity. RESULTS: The Cronbach's α coefficients ranged 0.833-0.960, well above the acceptable level of 0.70. Correlation analysis showed that each item had a strong correlation with the corresponding domain, but a weak correlation with other domains. Confirmatory factor analysis indicated that the comparative fit index was 0.94, higher than the acceptable level of 0.90.CONCLUSION: The Chinese version of the NDI is a reliable and valid scale for measuring health-related quality of life and disease severity in Chinese patients with FD. 展开更多
关键词 Nepean Dyspepsia index Functional dyspepsia Health-related quality of life Validation studies Questionaires
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Evaluation index system of shared energy storage market towards renewable energy accommodation scenario:A China’s Qinghai province context 被引量:16
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作者 Baomin Fang Weiqiang Qiu +3 位作者 Maochun Wang Wei Zhou Zhenzhi Lin Fushuan Wen 《Global Energy Interconnection》 EI CAS CSCD 2022年第1期77-95,共19页
With the ever-increased installed capacity of renewable energy generation units in a power system,the so-called shared energy storage(SES),a novel business model under the umbrella of the shared economy principle,has ... With the ever-increased installed capacity of renewable energy generation units in a power system,the so-called shared energy storage(SES),a novel business model under the umbrella of the shared economy principle,has the potential to play an essential role in the accommodation of renewable energy generation.However,unified evaluation standards and methods,which can help decision-makers analyze the performance of the SES market,are still not available.In this paper,an evaluation index system of the SES market is designed based on the trading rules of China’s Qinghai province and the structure-conduct-performance(SCP)analytical model.Moreover,the definition and characteristics of the indices,which can show the performance of the SES market from different perspectives,are given.Furthermore,the ideal cases are presented as the evaluation benchmark based on the development expectation of the SES market,and the analytic hierarchy process(AHP)and the technique for order preference by similarity to an ideal solution(TOPSIS)are applied to evaluate the SES market comprehensively.Finally,a case study based on actual data of the SES trading pilot project in Qinghai shows that the evaluation index system can reflect the operation status,existing problems and influencing factors of the SES market. 展开更多
关键词 Shared energy storage(SES) Renewable energy accommodation scenario Evaluation index system Ancillary service market
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A Modified Temperature-Vegetation Dryness Index(MTVDI)for Assessment of Surface Soil Moisture Based on MODIS Data 被引量:1
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作者 WANG Hao LI Zongshan +2 位作者 ZHANG Weijuan YE Xin LIU Xianfeng 《Chinese Geographical Science》 SCIE CSCD 2022年第4期592-605,共14页
Spatio-temporal dynamic monitoring of soil moisture is highly important to management of agricultural and vegetation eco-systems.The temperature-vegetation dryness index based on the triangle or trapezoid method has b... Spatio-temporal dynamic monitoring of soil moisture is highly important to management of agricultural and vegetation eco-systems.The temperature-vegetation dryness index based on the triangle or trapezoid method has been used widely in previous studies.However,most existing studies simply used linear regression to construct empirical models to fit the edges of the feature space.This requires extensive data from a vast study area,and may lead to subjective results.In this study,a Modified Temperature-Vegetation Dryness Index(MTVDI)was used to monitor surface soil moisture status using MODIS(Moderate-resolution Imaging Spectroradiometer)remote sensing data,in which the dry edge conditions were determined at the pixel scale based on surface energy balance.The MTVDI was validated by field measurements at 30 sites for 10 d and compared with the Temperature-Vegetation Dryness Index(TVDI).The results showed that the R^(2) for MTVDI and soil moisture obviously improved(0.45 for TVDI,0.69 for MTVDI).As for spatial changes,MTVDI can also better reflect the actual soil moisture condition than TVDI.As a result,MTVDI can be considered an effective method to monitor the spatio-temporal changes in surface soil moisture on a regional scale. 展开更多
关键词 surface soil moisture Temperature-Vegetation Dryness index(TVDI) vegetation index MODIS Modified Temperature-Vegetation Dryness index(MTVDI)
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Bispectral index monitoring as an adjunct to nurse-administered combined sedation during endoscopic retrograde cholangiopancreatography 被引量:4
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作者 Se Young Jang Hyun Gu Park +7 位作者 Min Kyu Jung Chang Min Cho Soo Young Park Seong Woo Jeon Won Young Tak Young Oh Kweon Sung Kook Kim Young Hoon Jeon 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第43期6284-6289,共6页
AIM:To determine whether bispectral index (BIS) monitoring is useful for propofol administration for deep sedation during endoscopic retrograde cholangiopancreatography (ERCP). METHODS:Fifty-nine consecutive patients ... AIM:To determine whether bispectral index (BIS) monitoring is useful for propofol administration for deep sedation during endoscopic retrograde cholangiopancreatography (ERCP). METHODS:Fifty-nine consecutive patients with a variety of reasons for ERCP who underwent the procedure at least twice between 1 July 2010 and 30 November 2010. This was a randomized cross-over study, in which each patient underwent ERCP twice, once with BIS monitoring and once with control monitoring. Whether BIS monitoring was done during the first or second ERCP procedure was random. Patients were intermittently administered a mixed regimen including midazolam, pethidine, and propofol by trained nurses. The nurse used a routine practice to monitor sedation using the Modified Observer's Assessment of Alertness/Sedation (MOAA/S) scale or the BIS monitoring. The total amount of midazolam and propofol used and serious side effects were compared between the BIS and control groups. RESULTS:The mean total propofol dose administered was 53.1 ± 32.2 mg in the BIS group and 54.9 ± 30.8 mg in the control group (P = 0.673). The individual propofol dose received per minute during the ERCP procedure was 2.90 ± 1.83 mg/min in the BIS group and 3.44 ± 2.04 mg in the control group (P = 0.103). The median value of the MOAA/S score during the maintenance phase of sedation was comparable for the two groups. The mean BIS values throughout the procedure (from insertion to removal of the endoscope) were 76.5 ± 8.7 for all 59 patients in using the BIS monitor. No significant differences in the frequency of < 80% oxygen saturation, hypotension (< 80 mmHg), or bradycardia (< 50 beats/min) were observed between the two study groups. Four cases of poor cooperation occurred, in which the procedure should be stopped to add the propofol dose. After adding the propofol, the procedure could be conducted successfully (one case in the BIS group, three cases in the control group). The endoscopist rated patient sedation as excellent for all patients in both groups. All patients in both groups rated their level of satisfaction as high (no discomfort). During the post-procedural follow-up in the recovery area, no cases of clinically significant hypoxic episodes were recorded in either group. No other postoperative side effects related to sedation were observed in either group. CONCLUSION:BIS monitoring trend to slighlty reduce the mean propofol dose. Nurse-administered propofol sedation under the supervision of a gastroenterologist may be considered an alternative under anesthesiologist. 展开更多
关键词 Conscious sedation Bispectral index monitors Pancreatic neoplasm Endoscopic retrograde cholangiopancreatography
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Establishing evaluation index system for desertification of Keerqin sandy land with remote sensing data 被引量:4
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作者 FAN Wen-yi ZHANG Wen-hua +1 位作者 YU Su-fang LIU Dan 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第3期209-212,共4页
Keerqin sand land is located in the transitional terrain between the Northeast Plain and Inner Mongolia (42°41′-45°15′N, 118°35′-123°30′ E) in Northeast China and it is seriously affected by ... Keerqin sand land is located in the transitional terrain between the Northeast Plain and Inner Mongolia (42°41′-45°15′N, 118°35′-123°30′ E) in Northeast China and it is seriously affected by desertification. According to the configuration and ecotope of the earths surface, the coverage of vegetation, occupation ratio of bare sandy land and the soil texture were selected as evaluation indexes by using the field investigation data. The evaluation index system of Keerqin sandy desertification was established by using Remote Sensing data. and the occupation ratio of bare sandy land was obtained by mixed spectrum model. This index system is validated by the field investioation data and results indicate that it is suitable for the desertification evaluation of Keerqin.Foundation Item: This study is supported by a grant from the National Natural Science Foundation of China (No. 30371192) 展开更多
关键词 Sandy desertification Evaluation index system Remote sensing data Keerqin sandy land Inner Mongolia
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Vegetation/Soil Synthesis Water Index Using MODIS Data 被引量:5
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作者 SONG Xiao-ning ZHAO Ying-shi LIU Zhen-hua 《Journal of China University of Mining and Technology》 EI 2005年第3期222-226,共5页
In consideration of the spectral character of MODIS (Moderate Resolution Imaging Spectroradiometer) dataand the reflective spectrum of vegetation and soil, NDVI (Normalized Difference Vegetation Index) and NDWI (Nor-m... In consideration of the spectral character of MODIS (Moderate Resolution Imaging Spectroradiometer) dataand the reflective spectrum of vegetation and soil, NDVI (Normalized Difference Vegetation Index) and NDWI (Nor-malized Difference Water Index) are deduced using one visible band (0.66μm) and two near-infrared bands (0.86μm,1.24 μm). Vegetation canopy temperature is derived using two thermal infrared bands (8.6 μm and 11μm). Then thevegetation/soil synthesis water index (VSWI) is acquired through analyzing the coupling character of three indexeswhich can reflect the water condition of vegetation. Finally, the synthesis index is verified by equivalent water contentof a single leaf. The matching results show that the synthesis index is directly proportional to the modeled data,which means that the vegetation water content can be reflected using the synthesis index effectively. 展开更多
关键词 MODIS NDVI NDWI vegetation/soil synthesis water index
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SLC-index: A scalable skip list-based index for cloud data processing 被引量:2
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作者 HE Jing YAO Shao-wen +1 位作者 CAI Li ZHOU Wei 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第10期2438-2450,共13页
Due to the increasing number of cloud applications,the amount of data in the cloud shows signs of growing faster than ever before.The nature of cloud computing requires cloud data processing systems that can handle hu... Due to the increasing number of cloud applications,the amount of data in the cloud shows signs of growing faster than ever before.The nature of cloud computing requires cloud data processing systems that can handle huge volumes of data and have high performance.However,most cloud storage systems currently adopt a hash-like approach to retrieving data that only supports simple keyword-based enquiries,but lacks various forms of information search.Therefore,a scalable and efficient indexing scheme is clearly required.In this paper,we present a skip list-based cloud index,called SLC-index,which is a novel,scalable skip list-based indexing for cloud data processing.The SLC-index offers a two-layered architecture for extending indexing scope and facilitating better throughput.Dynamic load-balancing for the SLC-index is achieved by online migration of index nodes between servers.Furthermore,it is a flexible system due to its dynamic addition and removal of servers.The SLC-index is efficient for both point and range queries.Experimental results show the efficiency of the SLC-index and its usefulness as an alternative approach for cloud-suitable data structures. 展开更多
关键词 cloud computing distributed index cloud data processing skip list
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