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The validity of automatic methods for estimating maturation stage in young athletes:A comparison of the Maturo smartphone application and sport science expert evaluations
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作者 Ximing Shang Jorge Arede +1 位作者 Pedro Couto Nuno Leite 《Journal of Sport and Health Science》 2025年第4期32-39,共8页
Background: Biological maturation refers to the progressive process through which individuals transition toward an adult state during growth and development. To address the challenges posed by differences in biologica... Background: Biological maturation refers to the progressive process through which individuals transition toward an adult state during growth and development. To address the challenges posed by differences in biological maturity and the limitations of existing testing methods, particularly in adolescent sports contexts, there is a pressing need for a non-invasive method that is convenient, accurate, and broadly applicable to monitor the biological maturity of adolescent athletes comprehensively. In response to this need, a maturity assessment method based on the smartphone application Maturo has been developed. This study evaluates the accuracy and validity of the Maturo software, an automated tool for estimating biological age and related maturation metrics.Methods: A sample of 103 actively training teenage athletes aged 9-17 years. The sample included 76 males(age = 11.74 ± 1.55 years, mean ±SD) and 27 females(age = 13.95 ± 1.40 years), all without medical conditions that might impact growth or development.Results: Compared to traditional expert evaluations, the intraclass correlation coefficients(ICCs) and Pearson correlation coefficients demonstrated reliable positive correlations and significant agreement between the Maturo software and expert methods across multiple metrics, such as biological age(ICC = 0.965, R = 0.97), corrected biological age(ICC = 0.973, R = 0.99), predicted adult height(ICC = 0.991, R = 0.99), and percentage of adult height achieved(ICC = 0.955, R = 0.97). The Bland-Altman plots provided additional evidence of the validity of the Maturo software estimations, showing low systematic error in most measures. The linear regression analysis produced excellent adjusted R2values: 0.95for biological age and 0.99 for anticipated adult height. The Maturo approach demonstrated a high level of dependability in classifying teenagers into groups based on their maturity status and timing. The κ coefficients of 0.93 for maturity status and 0.82 for maturity timing indicate a nearly perfect agreement with the expert technique.Conclusion: While the Maturo software's non-invasive nature, cost-effectiveness, and ease of use could make it a potential tool for regular monitoring of growth and maturation in young athletes, its promising results in assessing maturation should be interpreted with caution due to limitations such as sample size and demographic constraints. Further longitude research with larger and more diverse populations is needed to validate these preliminary findings and strengthen the evidence for its broader applicability. 展开更多
关键词 Maturation assessment Youth athletes Maturo software Biological maturation estimation ANTHROPOMETRY
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Estimating the final fatalities using early reported death count from the 2023 Kahramanmaras,Türkiye,M_(S) 8.0-7.9 earthquake doublet and revising the estimates over time
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作者 Yan Liu Zitao Wang Xuemin Zhang 《Earthquake Research Advances》 2025年第2期5-12,共8页
Earthquakes can cause significant damage and loss of life,necessitating immediate assessment of the resulting fatalities.Rapid assessment and timely revision of fatality estimates are crucial for effective emergency d... Earthquakes can cause significant damage and loss of life,necessitating immediate assessment of the resulting fatalities.Rapid assessment and timely revision of fatality estimates are crucial for effective emergency decisionmaking.This study using the February 6,2023,M_(S)8.0 and M_(S)7.9 Kahramanmaras,Türkiye earthquakes as an example to estimate the ultimate number of fatalities.An early Quick Rough Estimate(QRE)based on the number of deaths reported by the Disaster and Emergency Management Presidency of Türkiye(AFAD)is conducted,and it dynamically adjusts these estimates as new data becomes available.The range of estimates of the final number of deaths can be calculated as 31384–56475 based on the"the QRE of the second day multiplied by 2–3" rule,which incorporates the reported final deaths 50500.The Quasi-Linear and Adaptive Estimation(QLAE)method adaptively adjusts the final fatality estimate within two days and predicts subsequent reported deaths.The correct order of magnitude of the final death toll can be estimated as early as 13 hr after the M_(S)8.0 earthquake.In addition,additional earthquakes such as May 12,2008,M_(S)8.1 Wenchuan earthquake(China),September 8,2023,M_(S)7.2 Al Haouz earthquake(Morocco),November 3,2023,M_(S)5.8 Mid-Western Nepal earthquake,December 18,2023,M_(S)6.1 Jishishan earthquake(China),January 1,2024,M_(S)7.2 Noto Peninsula earthquake(Japan)and August 8,2023,Maui,Hawaii,fires are added again to verified the correctness of the model.The fatalities from the Maui fires are found to be approximately equivalent to those resulting from an M_(S)7.4 earthquake.These methods complement existing frameworks such as Quake Loss Assessment for Response and Mitigation(QLARM)and Prompt Assessment of Global. 展开更多
关键词 Kahramanmaras earthquake Earthquake fatality Human loss estimates Seismic risk 2023 Maui fires
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A sediment influx-outflux-accommodation composite index-based method for estimating sediment storage in debris flow channels
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作者 LEI Xiaohu ZHANG Shaojie +1 位作者 YANG Hongjuan WEI Fangqiang 《Journal of Mountain Science》 2025年第6期1889-1911,共23页
The distribution of the sediment material storage quantity along the debris flow channels(SMSQ_DFC)can provide a foundation for runoffgenerated debris flow prediction or susceptibility assessment.Current models for es... The distribution of the sediment material storage quantity along the debris flow channels(SMSQ_DFC)can provide a foundation for runoffgenerated debris flow prediction or susceptibility assessment.Current models for estimating SMSQ_DFC do not consider the capacity of the channel cross-section to accommodate sediment materials.This accommodation condition serves as a limiting factor in determining whether the expected surplus of sediment materials can ultimately be stored.To address this issue,a mass-conservative index was used to represent the balance of deposit materials at any cross-section,considering the influx from upstream,outflux to downstream,and accommodation capacity.Based on this index,a new model for estimating SMSQ_DFC was developed and subsequently evaluated.The evaluation results show that the model meets the accuracy requirements with average error rates of 14.06%for self-validation and 14.81%for generalization ability validation.To assess its practical applications,the model was applied to the Yeniu Gully in Wenchuan County,Sichuan Province,an area with detailed field survey data.The results show that the model exhibits a commendable performance.Compared to traditional theoretical and semi-theoretical statistical models,our model is easier to use(input parameters can be obtained using Geographic Information Systems(GIS)).The modeling parameters chosen in this study have more theoretical significance than those used in existing purely statistical models,offering more effective technical support for estimating SMSQ_DFC. 展开更多
关键词 Debris flow deposit materials Sediment influx-outflux-accommodation index Sediment materials distribution along channels Deposit materials estimation model Channel bed deposits Debris flow provenance materials
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Chronic kidney disease in geriatric patients:Estimating glomerular filtration rate in older patients with comorbidities
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作者 Guido Gembillo Luca Soraci Domenico Santoro 《World Journal of Nephrology》 2025年第2期178-181,共4页
Aging is an inevitable process that is usually measured by chronological age,with people aged 65 and over being defined as"older individuals".There is disagreement in the current scientific literature regard... Aging is an inevitable process that is usually measured by chronological age,with people aged 65 and over being defined as"older individuals".There is disagreement in the current scientific literature regarding the best methods to estimate glomerular filtration rate(eGFR)in older adults.Several studies suggest the use of an age-adjusted definition to improve accuracy and avoid overdiagnosis.In contrast,some researchers argue that such changes could complicate the classification of chronic kidney disease(CKD).Several formulas,including the Modification of Diet in Renal Disease,CKD-Epidemiology Collaboration,and Cockcroft-Gault equations,are used to estimate eGFR.However,each of these formulas has significant limitations when applied to older adults,primarily due to sarcopenia and malnutrition,which greatly affect both muscle mass and creatinine levels.Alternative formulas,such as the Berlin Initiative Study and the Full Age Spectrum equations,provide more accurate estimates of values for older adults by accounting for age-related physiological changes.In frail older adults,the use of cystatin C leads to better eGFR calculations to assess renal function.Accurate eGFR measurements improve the health of older patients by enabling better medication dosing.A thorough approach that includes multiple calibrated diagnostic methods and a detailed geriatric assessment is necessary for the effective management of kidney disease and other age-related conditions in older adults. 展开更多
关键词 Chronic kidney disease Estimated glomerular filtration rate Renal alterations Geriatric patients Chronic Kidney Disease-Epidemiology Collaboration Modification of Diet in Renal Disease Cockcroft-Gault formula Berlin initiative study Full age spectrum equation
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Holevo bound independent of weight matrices for estimating two parameters of a qubit
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作者 牛畅 郁司夏 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期137-143,共7页
Holevo bound plays an important role in quantum metrology as it sets the ultimate limit for multi-parameter estimations,which can be asymptotically achieved.Except for some trivial cases,the Holevo bound is implicitly... Holevo bound plays an important role in quantum metrology as it sets the ultimate limit for multi-parameter estimations,which can be asymptotically achieved.Except for some trivial cases,the Holevo bound is implicitly defined and formulated with the help of weight matrices.Here we report the first instance of an intrinsic Holevo bound,namely,without any reference to weight matrices,in a nontrivial case.Specifically,we prove that the Holevo bound for estimating two parameters of a qubit is equivalent to the joint constraint imposed by two quantum Cramér–Rao bounds corresponding to symmetric and right logarithmic derivatives.This weightless form of Holevo bound enables us to determine the precise range of independent entries of the mean-square error matrix,i.e.,two variances and one covariance that quantify the precisions of the estimation,as illustrated by different estimation models.Our result sheds some new light on the relations between the Holevo bound and quantum Cramer–Rao bounds.Possible generalizations are discussed. 展开更多
关键词 quantum metrology quantum Fisher information Holevo bound quantum multi-parameter estimation
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Estimating wheat spike-leaf composite indicator(SLI)dynamics by coupling spectral indices and machine learning
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作者 Haiyu Tao Ruiheng Zhou +6 位作者 Yining Tang Wanyu Li Xia Yao Tao Cheng Yan Zhu Weixing Cao Yongchao Tian 《The Crop Journal》 SCIE CSCD 2024年第3期927-937,共11页
The contribution of spike photosynthesis to grain yield(GY)has been overlooked in the accurate spectral prediction of yield.Thus,it’s essential to construct and estimate a yield-related phenotypic trait considering s... The contribution of spike photosynthesis to grain yield(GY)has been overlooked in the accurate spectral prediction of yield.Thus,it’s essential to construct and estimate a yield-related phenotypic trait considering spike photosynthesis.Based on field and spectral reflectance data from 19 wheat cultivars under two nitrogen fertilization conditions in two years,our objectives were to(i)construct a yield-related phenotypic trait(spike–leaf composite indicator,SLI)accounting for the contribution of the spike to photosynthesis,(ii)develop a novel spectral index(enhanced triangle vegetation index,ETVI3)sensitive to SLI,and(iii)establish and evaluate SLI estimation models by integrating spectral indices and machine learning algorithms.The results showed that SLI was sensitive to nitrogen fertilizer and wheat cultivar variation as well as a better predictor of yield than the leaf area index.ETVI3 maintained a strong correlation with SLI throughout the growth stage,whereas the correlations of other spectral indices with SLI were poor after spike emergence.Integrating spectral indices and machine learning algorithms improved the estimation accuracy of SLI,with the most accurate estimates of SLI showing coefficient of determination,root mean square error(RMSE),and relative RMSE values of 0.71,0.047,and 26.93%,respectively.These results provide new insights into the role of fruiting organs for the accurate spectral prediction of GY.This high-throughput SLI estimation approach can be applied for wheat yield prediction at whole growth stages and may be assisted with agronomical practices and variety selection. 展开更多
关键词 Wheat spike photosynthesis Yield-related phenotypic trait Spectral indices Machine learning Estimation
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Dual-environment feature fusion-based method for estimating building-scale population distributions
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作者 Guangyu Liu Rui Li +4 位作者 Jing Xia Zhaohui Liu Jing Cai Huayi Wu Mingjun Peng 《Geo-Spatial Information Science》 CSCD 2024年第6期1943-1958,共16页
Information on the population distribution at the building scale can help governments make supplemental decisions to address complex urban management issues.However,the discontinuity and strong spatial heterogeneity o... Information on the population distribution at the building scale can help governments make supplemental decisions to address complex urban management issues.However,the discontinuity and strong spatial heterogeneity of research units at the building scale make it challenging to fuse multi-source geographic data,which causes significant errors in population estimation.To address this problem,this study proposes a method for population estimation at the building scale based on Dual-Environment Feature Fusion(DEFF).The dual environments of buildings were constructed by splitting the physical boundaries and extracting features suitable for the dual-environment scale from multi-source geographic data to describe the complex environmental features of buildings.Meanwhile,Data Quality Weighting based Technique for Order of Preference by Similarity to Ideal Solution(DQW-TOPSIS)method was proposed to assign appropriate weights to the features of the external environment for better feature fusion.Finally,a regression model was established using dual-environment features for building-scale population estimation.The experimental areas chosen for this study were Jianghan and Wuchang Districts,both located in Wuhan City,China.The estimated results of the DEFF were compared with those of the ablation experiments,as well as three publicly accessible population datasets,specifically LandScan,WorldPop,and GHS-POP,at the community scale.The evaluation results showed that DEFF had an R2 of approximately 0.8,Mean Absolute Error(MAE)of approximately 1200,Root Mean Square Error(RMSE)of approximately 1700,and both Mean Absolute Percentage Error(MAPE)and Symmetric Mean Absolute Percentage Error(SMAPE)of approximately 26%,indicating an improved performance and verifying the validity of the proposed method for fine-scale population estimation. 展开更多
关键词 Building scale multi-source data fusion estimation of population distribution dual environment Data Quality Weighting based Technique for Order of Preference by Similarity to Ideal Solution(DQW-TOPSIS)
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Estimating the Input Power of a Power Plant Using the Efficiency of the Inverter
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作者 Toussaint Tilado Guingane Sosthène Tassembedo +3 位作者 Eric Korsaga Dominique Bonkoungou Zacharie Koalaga François Zougmore 《Smart Grid and Renewable Energy》 2024年第3期99-106,共8页
The study focuses on estimating the input power of a power plant from available data, using the theoretical inverter efficiency as the key parameter. The paper addresses the problem of missing data in power generation... The study focuses on estimating the input power of a power plant from available data, using the theoretical inverter efficiency as the key parameter. The paper addresses the problem of missing data in power generation systems and proposes an approach based on the efficiency formula widely documented in the literature. In the absence of input data, this method makes it possible to estimate the plant’s input power using data extracted from the site, in particular that provided by the Ministry of the Environment. The importance of this study lies in the need to accurately determine the input power in order to assess the overall performance of the energy system. 展开更多
关键词 ESTIMATION Data MISSING INPUT Power EFFICIENCY INVERTER
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Comparison on Winter Wheat Yield Estimating Models Based on Radarsat-2 and HJ Satellite in Huaihe River Region 被引量:1
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作者 范伟 陈磊 +2 位作者 陈娟 闫洪凯 刘韬 《Agricultural Science & Technology》 CAS 2016年第4期1019-1023,共5页
The establishment of crop yield estimating model based on microwave and optical satellite images can conduct the mutual verification of the accuracy of the reported crop yield and the precision of the estimating model... The establishment of crop yield estimating model based on microwave and optical satellite images can conduct the mutual verification of the accuracy of the reported crop yield and the precision of the estimating model. With Shou County and Huaiyuan County of Anhui Province as the experimental fields of winter wheat producing areas, the linear winter wheat yield estimating models were established by adopting backscattering coefficient and Normalized Difference Vegetation Index(NDVI) based on images from the synthetic aperture radar(SAR)—RDARSAT-2 and HJ satellite photographed in mid-April and early May, 2014, and then comparisons were conducted on the accuracy of the yield estimating models. The accuracies of the yield estimating models established using co-polarized(HH) and cross-polarized(HV) modes of SAR in Jiangou Town, Shou County were 68.37% and 74.01%, respectively, while the accuracies in Longkang Town, Huaiyuan County were 63.10%and 69.10%, respectively. Accuracies of yield estimating models established by HJ satellite data were 69.52% and 66.43% in Shou County and Huaiyuan County, respectively. Accuracies of winter yield estimating model based on HJ satellite data and that based on SAR were closed, and the yield difference of winter wheat in the lodging region was analyzed in detail. The model results laid the foundation and accumulated experience for the verification, parameters correction and promotion of the winter wheat yield estimating model. 展开更多
关键词 Winter wheat yield estimating model Synthetic aperture radar RADARSAT-2 HJ satellite Model comparison
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ADAPTIVE ESTIMATING DETAIL PRESERVING FILTER FOR IMAGE PROCESSING
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作者 李向吉 丁润涛 《Transactions of Tianjin University》 EI CAS 1998年第2期68-71,共4页
A new adaptive detail preserving filter for image processing is presented.By comparing the difference of the values evaluated in the different directions or regions,this filter can decide wh... A new adaptive detail preserving filter for image processing is presented.By comparing the difference of the values evaluated in the different directions or regions,this filter can decide which region (homogeneous region or detail region) the filtering pixels belong to and then apply different filtering schemes.This filter has better performance of noise filtering and detail preserving than the multistage median filter (MMF).It can be applied especially to the images simultaneously corrupted by Gaussian noise and impulsive noise,and is simple in computation and implementation. 展开更多
关键词 estimating detail preserving filtering adaptive filtering
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A Novel Estimating Method for Steering Efficiency of the Driver with Electromyography Signals 被引量:6
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作者 LIU Yahui JI Xuewu +1 位作者 HAYAMA Ryouhei MIZUNO Takahiro 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2014年第3期460-467,共8页
The existing research of steering efficiency mainly focuses on the mechanism efficiency of steering system, aiming at designing and optimizing the mechanism of steering system. In the development of assist steering sy... The existing research of steering efficiency mainly focuses on the mechanism efficiency of steering system, aiming at designing and optimizing the mechanism of steering system. In the development of assist steering system especially the evaluation of its comfort, the steering efficiency of driver physiological output usually are not considered, because this physiological output is difficult to measure or to estimate, and the objective evaluation of steering comfort therefore cannot be conducted with movement efficiency perspective. In order to take a further step to the objective evaluation of steering comfort, an estimating method for the steering efficiency of the driver was developed based on the research of the relationship between the steering force and muscle activity. First, the steering forces in the steering wheel plane and the electromyography (EMG) signals of the primary muscles were measured. These primary muscles are the muscles in shoulder and upper ann which mainly produced the steering torque, and their functions in steering maneuver were identified previously. Next, based on the multiple regressions of the steering force and EMG signals, both the effective steering force and the total force capacity of driver in steering maneuver were calculated. Finally, the steering efficiency of driver was estimated by means of the estimated effective force and the total force capacity, which represented the information of driver physiological output of the primary muscles. This research develops a novel estimating method for driver steering efficiency of driver physiological output, including the estimation of both steering force and the force capacity of primary muscles with EMG signals, and will benefit to evaluate the steering comfort with an objective perspective. 展开更多
关键词 ELECTROMYOGRAPHY muscle activity steering efficiency estimating
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Approach to estimating non-point pollutant load removal rates based on water environmental capacity: a case study in Shenzhen 被引量:1
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作者 刘梁 刘安 管运涛 《Journal of Southeast University(English Edition)》 EI CAS 2014年第2期143-149,共7页
An innovative approach based on water environmental capacity for non-point source NPS pollution removal rate estimation was discussed by using both univariate and multivariate data analysis.Taking Shenzhen city as the... An innovative approach based on water environmental capacity for non-point source NPS pollution removal rate estimation was discussed by using both univariate and multivariate data analysis.Taking Shenzhen city as the study case a 67% to 74% NPS pollutant load removal rate can lead to meeting the chemical oxygen demand COD pollution control target for most watersheds.In contrast it is hardly to achieve the ammonia nitrogen NH4-N total phosphorus TP and biological oxygen demand BOD5 pollution control target by simply removing NPS pollutants. This highlights that the pollution control strategies should be taken according to different pollutant species and sources in different watersheds rather than one-size-fits-all . 展开更多
关键词 environmental capacity estimation non-point source (NPS) pollution removal rate control strategy
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Estimating Synechococcus spp. growth rates and grazingpressure by heterotrophic nanoplankton in theEnglish Channel and the Celtic Sea 被引量:7
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作者 Ning Xiuren and Daniel Vaulot 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1992年第2期255-273,共19页
-Marine chroococcoid phycoerythrin - containing Synechococcus spp. recently have been implicated as a substantial component of the photosynthetic picoplankton in the ocean. Although the importance of Synechococcus as ... -Marine chroococcoid phycoerythrin - containing Synechococcus spp. recently have been implicated as a substantial component of the photosynthetic picoplankton in the ocean. Although the importance of Synechococcus as food sources for heterotrophic nanoplankton are now recognized, the information about its cycling of biomass and diel patterns is limited and the methodology used varies according to different authors. A selective metabolic inhibitor method was used to allow simultanous estimation of both growth rates and grazing disappearance rates of Synechococcus. Results obtained in the English Channel show growth rates ranging from 0. 25 to 0. 72 d-1 with an average value of 0. 51 d -1and grazing disappearance rates ranged from 0. 21 to 0. 64 d-1 (mean = 0. 44 d-1). Offshore in the Celtic Sea of the Northeast Atlantic Ocean, both rates were lower than in the channel. The similarity between average growth and grazing rates suggests a rapid recycling of Synechococcus biomass. In diel pattern, Synechococcus grazing mortality rates were higher during the day (mean = 0. 61 d-1) than during the night (mean = 0. 21d-1) in all the experiments. A positive correlation was observed between growth rates and in situ temperature ranged from 9 to 20 ℃. Sire-fractionated experiments demonstrate that up to about 7 0 % of Synechococcus disappearance could be attributed to the grazer smaller than 2 μm in diameter. The variations of Synechococcus cell characteristics such as size and phycoerythin contents in the growth and grazing experiments were determined with a flow cytometer. The methodology recently used on estimating dynamics of Synechococcus population is reviewed. 展开更多
关键词 estimating Synechococcus spp growth rates and grazingpressure by heterotrophic nanoplankton in theEnglish Channel and the Celtic Sea
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Predictive value of neutrophil-to-lymphocyte ratio and other inflammatory indicators in estimating clinical severity of coronavirus disease 被引量:3
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作者 Guang-qing Yu Qing Zhang +1 位作者 Run-chang Wang Shi-qin Jiang 《World Journal of Emergency Medicine》 SCIE CAS CSCD 2021年第1期79-80,共2页
Dear editor,The recent outbreak of coronavirus disease(COVID-19)has become a major public health issue caused by 2019 novel coronavirus(2019-nCoV).[1]Severe COVID-19 patients may reveal a dysregulated immune response ... Dear editor,The recent outbreak of coronavirus disease(COVID-19)has become a major public health issue caused by 2019 novel coronavirus(2019-nCoV).[1]Severe COVID-19 patients may reveal a dysregulated immune response that allows the development of v iral hyperinfl ammation.[2]In the fight against COVID-19,inflammatory parameters towards illness severity should be identified to improve the prognosis of patients.In this study,we aimed to assess the discriminative ability of several infl ammation indicators in severe COVID-19 infection. 展开更多
关键词 SEVERITY PROGNOSIS estimating
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Estimating HIV Incidence Rates among MSM in an Urban Area of Chongqing Using Three Approaches 被引量:3
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作者 HAN Mei PAN Ping Liang +5 位作者 WU Guo Hui ZHOU Chao YAO Yuan LUO Juan ZOU Jing Bo ZHANG Bo 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2017年第12期913-916,共4页
To evaluate the HIV pandemic in Chongqing, the pooled PCR, IgG-capture BED enzyme immunoassay (BED-CEIA), and cohort observations were used to estimate the HIV incidences among men who have sex with men (MSM). 617... To evaluate the HIV pandemic in Chongqing, the pooled PCR, IgG-capture BED enzyme immunoassay (BED-CEIA), and cohort observations were used to estimate the HIV incidences among men who have sex with men (MSM). 617 MSM subjects completed the survey at a voluntary counseling and testing (VCT) site. The observed HIV incidence was 12.5 per 100 P-Ys (95% CI = 9.1-15.7). 展开更多
关键词 estimating HIV Urban Area
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Application of Monte-Carlo statistical experiments in design of ocean engineering - Estimating the parameters, models and probabilities 被引量:2
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作者 Liu Defu, Shi Jiangang and Zhou Zhigang Department of Ocean Engineering and Naval Architecture, Tianjin University. Tianjin, China Business & Project Division China Offshore Industrial Corporation (COIC).No. 10 Beixiaojie,Yuetan,BeijingsChina 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1990年第4期587-597,共11页
Recently, some results have been acquired with the Monte- Carlo statistical experiments in the design of ocean en gineering. The results show that Monte-Carlo statistical experiments can be widely used in estimating t... Recently, some results have been acquired with the Monte- Carlo statistical experiments in the design of ocean en gineering. The results show that Monte-Carlo statistical experiments can be widely used in estimating the parameters of wave statistical distributions, checking the probability model of the long- term wave extreme value distribution under a typhoon condition and calculating the failure probability of the ocean platforms. 展开更多
关键词 estimating the parameters Application of Monte-Carlo statistical experiments in design of ocean engineering
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Improving Accuracy of Estimating Two-Qubit States with Hedged Maximum Likelihood 被引量:1
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作者 殷琪 项国勇 +1 位作者 李传锋 郭光灿 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第3期1-5,共5页
As a widely used reconstruction algorithm in quantum state tomography, maximum likelihood estimation tends to assign a rank-deficient matrix, which decreases estimation accuracy for certain quantum states. Fortunately... As a widely used reconstruction algorithm in quantum state tomography, maximum likelihood estimation tends to assign a rank-deficient matrix, which decreases estimation accuracy for certain quantum states. Fortunately, hedged maximum likelihood estimation (HMLE) [Phys. Rev. Lett. 105 (2010)200504] was proposed to avoid this problem. Here we study more details about this proposal in the two-qubit case and further improve its performance. We ameliorate the HMLE method by updating the hedging function based on the purity of the estimated state. Both performances of HMLE and ameliorated HMLE are demonstrated by numerical simulation and experimental implementation on the Werner states of polarization-entangled photons. 展开更多
关键词 MLE Improving Accuracy of estimating Two-Qubit States with Hedged Maximum Likelihood
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Application of Bit Error Rate Information Based on Weighted Error Estimating Code 被引量:1
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作者 Liu Yu Li Qing +1 位作者 Li Bin Zhang Lin 《China Communications》 SCIE CSCD 2012年第6期82-90,共9页
Error Estimating Code (EEC) is a new channel coding method to estimate the Bit Error Rate (BER) information of the transmitted sequence. However, the estimated BER is not precise enough if the practical value of BER i... Error Estimating Code (EEC) is a new channel coding method to estimate the Bit Error Rate (BER) information of the transmitted sequence. However, the estimated BER is not precise enough if the practical value of BER is high. A weighted EEC estimation method is proposed to improve the accuracy performance of BER estimation by classifying the raw estimation results into intervals and multiplying them by different coefficients separately. The applications of weighted EEC in modulation selection scheme and distributed video coding are discussed. Simulation results show that the EEC-based modulation selection method can achieve better performance at a cost of little redundancy and computation, and the EEC-based rate estimation method in distributed video coding can save the decoding time. 展开更多
关键词 channel coding BER estimation errorestimating code adaptive modulation selection distributed video coding
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Estimating Canopy Nitrogen Contents of an Apple Tree Using Hyperspectral Remote Sensing 被引量:1
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作者 Xicun ZHU Lulu GAO +2 位作者 Xianyi FANG Gengxing ZHAO Ling WANG 《遥感科学(中英文版)》 2016年第2期42-50,共9页
Estimating an apple tree canopy nitrogen contents using hyperspectral techniques is important in theoretical and realistic significance for fertilization and management.Taking 80 Fuji apple trees at the early fruiting... Estimating an apple tree canopy nitrogen contents using hyperspectral techniques is important in theoretical and realistic significance for fertilization and management.Taking 80 Fuji apple trees at the early fruiting stage as the research objects,the hyperspectral characteristics of the apple canopy were analyzed systematically.The apple canopy hyperspectral and the canopy nitrogen contents were measured respectively.The canopy hyperspectral characteristics under different nitrogen contents were analyzed and selected the sensitive wave bands.The apple canopy nitrogen content monitoring models were established by using multiple regression method,robust regression and BP neural network method.The results showed that the canopy hyperspectral reflectance had obvious differences under different nitrogen contents.The sensitive bands concentrate on 724~1136 nm.Estimation models based on hyperspectral indices are not ideal.Models based on robust regression(M regression)and BP neural network are better than multiple statistical model,and the accuracy of the BP neural network monitoring model is the best.The results of the study provide a certain reference for estimating apple nutrition using hyperspectral technology. 展开更多
关键词 APPLE Ttrees CANOPY NITROGEN CONTENTS Hyperspectrum estimating MODEL
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Application of Information Gain to Estimating the Seismic Tendency 被引量:2
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作者 Shen Ping,Shen Jing,and Feng GuozhengInstitute of Geophysics,SSB,Beijing 100081,China 《Earthquake Research in China》 1997年第2期44-50,共7页
Considering two seismic parameters,energy and the frequency of an earthquake as a whole from the definition of information gain in entropy,we study the information gain of M≥6.0 earthquakes from the world earthquake ... Considering two seismic parameters,energy and the frequency of an earthquake as a whole from the definition of information gain in entropy,we study the information gain of M≥6.0 earthquakes from the world earthquake catalogue during 1900-1992.The results show that the information gain decreases before strong earthquakes.Our study of the recent seismic tendency of large earthquakes shows that the probability of earthquakes with M≥8.5 is low for the near future around the world.The information gain technique provides a new approach to tracing and predicting earthquakes from the data of moderate and small earthquakes. 展开更多
关键词 Application of Information Gain to estimating the Seismic Tendency
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