calibration

摘要： To evaluate and predict liver fibrosis in patients with nonalcoholic fatty liver disease(NAFLD),several non-invasive scoring systems were built and widely used in the progress of diagnosis and treatment,which showed great diagnostic efficiency,such as aspartate aminotransferase to platelet ratio index,fibrosis-4 index,body mass index,aspartate aminotransferase to alanine aminotransferase ratio,diabetes score and NAFLD fibrosis score.Since the new concept of metabolic associated fatty liver disease(MAFLD)was proposed,the clinical application value of the non-invasive scoring systems mentioned above has not been assessed in MAFLD.The evaluation of the diagnostic performance of these non-invasive scoring systems will provide references for clinicians in the diagnosis of MAFLD.

摘要： BACKGROUND Acute respiratory distress syndrome(ARDS)is a major cause of death in patients with severe acute pancreatitis(SAP).Although a series of prediction models have been developed for early identification of such patients,the majority are complicated or lack validation.A simpler and more credible model is required for clinical practice.AIM To develop and validate a predictive model for SAP related ARDS.METHODS Patients diagnosed with AP from four hospitals located at different regions of China were retrospectively grouped into derivation and validation cohorts.Statistically significant variables were identified using the least absolute shrinkage and selection operator regression method.Predictive models with nomograms were further built using multiple logistic regression analysis with these picked predictors.The discriminatory power of new models was compared with some common models.The performance of calibration ability and clinical utility of the predictive models were evaluated.RESULTS Out of 597 patients with AP,139 were diagnosed with SAP(80 in derivation cohort and 59 in validation cohort)and 99 with ARDS(62 in derivation cohort and 37 in validation cohort).Four identical variables were identified as independent risk factors for both SAP and ARDS:heart rate[odds ratio(OR)=1.05;95%CI:1.04-1.07;P<0.001;OR=1.05,95%CI:1.03-1.07,P<0.001],respiratory rate(OR=1.08,95%CI:1.0-1.17,P=0.047;OR=1.10,95%CI:1.02-1.19,P=0.014),serum calcium concentration(OR=0.26,95%CI:0.09-0.73,P=0.011;OR=0.17,95%CI:0.06-0.48,P=0.001)and blood urea nitrogen(OR=1.15,95%CI:1.09-1.23,P<0.001;OR=1.12,95%CI:1.05-1.19,P<0.001).The area under receiver operating characteristic curve was 0.879(95%CI:0.830-0.928)and 0.898(95%CI:0.848-0.949)for SAP prediction in derivation and validation cohorts,respectively.This value was 0.892(95%CI:0.843-0.941)and 0.833(95%CI:0.754-0.912)for ARDS prediction,respectively.The discriminatory power of our models was improved compared with that of other widely used models and the calibration ability and clinical utility of the prediction models performed adequately.CONCLUSION The present study constructed and validated a simple and accurate predictive model for SAPrelated ARDS in patients with AP.

摘要： The semi-distributed SWAT (Soil and Water Assessment Tools) model was used in this study to model the sediment yield in the watershed of the Aghien lagoon with an area of 365 km2, located in the north of the district of Abidjan (South-East from C?te d’Ivoire). A sensitivity and uncertainty analysis, as well as calibration of the SWAT model, was conducted using the Sequential Uncertainty Adjustment Procedure (SUFI-2) which is one of the programs interfaced with SWAT in the SWAT-Cup package (SWAT-Calibration-Uncertainty Programs). Five parameters of the SWAT model were found to be more sensitive to sediment fluxes. These have been modified (calibration) sparingly in order to improve the reproduction of observed sediments data. Two measures were used to assess the uncertainty analysis of the model: P-factor and R-factor. The R2 and Nash-Sutcliffe (NS) coefficients of determination were used to assess the quality of the calibration. The P-factor obtained is 0.58 and the R-factor is 2.28. The NS and R2 coefficients in calibration over the period from June 2014 to January 2015 are 0.51 and 0.86 respectively. These values indicate correct consideration of uncertainties by the model and satisfactory calibration of the SWAT model for solid fluxes. Then, the model was used to simulate the sediment fluxes at the horizons 2040 (2035-2056), 2060 (2057-2078) and 2080 (2079-2100) in order to assess the impact of climate change on sediments in the watershed of the Aghien lagoon. The results indicate that sediment fluxes could increase in the future under the RCP 4.5 and RCP 8.5 scenarios. With RCP 4.5, sediment fluxes would increase on average by 14.42%. They could increase by 17.95% on average under RCP 8.5.

摘要： Precise measurements of the cavity forward(Vf)and reflected signals(Vr)are essential for characterizing other key parameters such as the cavity detuning and forward power.In practice,it is challenging to measure V_(f) and V_(r) precisely because of cross talk between the forward and reflected channels(e.g.,coupling between the cavity reflected and forward signals in a directional coupler with limited directivity).For DESY,a method based on the cavity differential equation was proposed to precisely calibrate the actual V_(f) and V_(r).In this study,we verified the validity and practicability of this approach for the Chinese ADS front-end demo superconducting linac(CAFe)facility at the Institute of Modern Physics and a compact energy recovery linac(cERL)test machine at KEK.At the CAFe facility,we successfully calibrated the actual V_(f) signal using this method.The result demonstrated that the directivity of directional couplers might seriously affect the accuracy of V_(f) measurement.At the cERL facility,we calibrated the Lorentz force detuning(LFD)using the actual Vf.Our study confirmed that the precise calibration of V_(f) significantly improves the accuracy of the cavity LFD measurement.

摘要： The purpose of this research is to demonstrate that a calibration curve can be obtained that can be used for any infiltration test, with the double ring method, as well as an equation that helps speed up data processing. The experimentation was carried out in eight points in Nicaragua, of which five were distributed in Managua and three in Rivas-Nandaime. These results can be used for purposes of other studies of interest. As a result, a calibration curve is obtained, and an expression equal to  is deduced, which will be the equation to determine the average infiltration of a field test occupying the double ring, for a total of 7 hours. And it is from the result that the texture of the soil can be determined by means of the indicator table. The basic methodology allowed analyzing the data since they are obtained, processed and analyzed, resulting in the calibration curve for infiltration tests. Finally, an equation was determined from the averages of the processed data, resulting in a correlation of 0.9976, above 0.5, which means it is very high and reliable.

摘要： Planetary ball mill is a powerful tool, which has been used for milling various materials for size reduction. The discrete element method (DEM) was used to simulate the dynamics of particle processes in a planetary ball mill. This work includes the calibration of DEM parameters to simulate a planetary ball mill using EDEM Altair 2021.2 software, which provides both faster workflows and results. The iterative input parameters changed to a close correlation between the simulation and experimental results are attained. The results showed that the standard tests could be used to generate various experimental reference values for the calibration. The numerical modeling results agree with theexperimental, indicating that the calibrated parameters are accurate.

摘要： Hydrogen Peroxide vapour is becoming more popular to use as a method of decontamination, particularly for medical equipment and enclosures. It is highly effective in terms of microbiological kill rates and has a variety of uses in healthcare. Although it is environmentally acceptable as it spontaneously decomposes into water and oxygen, concentration of hydrogen peroxide in the air needs to be monitored and controlled. A method of calibrating hydrogen peroxide vapor sensors is described which is based on the concentration of hydrogen peroxide in saturated vapour over a solution in water at a defined temperature. The saturated vapour is generated by bubbling dry air into a solution of hydrogen peroxide at a defined concentration and temperature. A vapour at a concentration of 0.7 ppm was produced and used to successfully calibrate a hydrogen peroxide sensor.

摘要： Inspired by box jellyfish that has distributed and complementary perceptive system,we seek to equip manipulator with a camera and an Inertial Measurement Unit(IMU)to perceive ego motion and surrounding unstructured environment.Before robot perception,a reliable and high-precision calibration between camera,IMU and manipulator is a critical prerequisite.This paper introduces a novel calibration system.First,we seek to correlate the spatial relationship between the sensing units and manipulator in a joint framework.Second,the manipulator moving trajectory is elaborately designed in a spiral pattern that enables full excitations on yaw-pitch-roll rotations and x-y-z translations in a repeatable and consistent manner.The calibration has been evaluated on our collected visual inertial-manipulator dataset.The systematic comparisons and analysis indicate the consistency,precision and effectiveness of our proposed calibration method.

摘要： The Indiana Department of Transportation (INDOT) spends approximately $30 to $60 million a year on deicing salt and operates a fleet of 1,000 winter operations trucks distributed among 140 locations. The entire fleet is now instrumented with location telematics, and all new trucks have integrated dash cameras, salt spreader application rate and plow up/plow down integrated into the telematics link. When winter storms occur, they have varying regional impacts and INDOT monitors several data sources including National Weather Service (NWS) live doppler, National Severe Storms Laboratory’s (NSSL) Multi-Radar Multi-Sensor (MRMS) products, road weather monitoring stations, and connected vehicles (CV) that provide roadway segment operating speeds. This paper discusses how telematics has been integrated to provide a comprehensive view of conditions, truck asset locations, and material distribution maps. The telematics identified widely varying salt spreader rates for the same calibration settings and equipment in preliminary analysis. A calibration box is developed to allow offload calibration to occur within 10 minutes without weighing or transporting the fleet vehicle. The method is deployed across six districts at INDOT for over 1000 snowplows. A sampling of eight trucks in the fleet found the proposed calibration method reduced salt application on average of 45%. This paper describes a series of telematics dashboards for managing winter operations and details the methods developed for 140 geographically distributed truck units to conduct simple, fast, and effective calibration.

摘要： At present,dental implant surgery mainly relies on the clinical experience of the doctor and the assistance of preoperative medical imaging.However,there are some problems in dental implant surgery,such as narrow space,sight obstruction,inaccurate positioning,and high requirements of doctors’proficiency.Therefore,a dental implant robot system(DIRS)guided by optical navigation is developed in this study,with an x-shaped tool and an irregular pentagonal tracer are designed for spatial registration and needle tip positioning strategy respectively.The coordinate system of each unit in DIRS is unified through system calibration,spatial registration,and needle tip positioning strategy.Then the surgical path is planned on the computed tomography(CT)images in the navigation software before operation.The automatic positioning method and the auxiliary positioning method can be used in the operation to achieve accurate positioning and assist doctors to complete the operation.The errors of spatial registration,needle tip positioning strategy,and the overall accuracy of the system were evaluated respectively,and the results showed that they all met the needs of clinical surgery.This study preliminarily verified the feasibility of the precise positioning method for dental surgery robots and provided certain ideas for subsequent related research.

摘要： Objective：To validate a semi-quantitative fbod-frequency questionnaire(FFQ)for evaluating nutrient intake among pregnant women in rural China．Design：Longitudinal validation study with interview administrated FFQs at start of third trimester(FFQ1)and repeated three months later prior to delivery(FFQ2)，with six repeated 24-hour recalls in between．Setting：Two rural counties in Shaanxi province，western China．Subjects：125 women at 23 to 26 weeks gestation recruited from June to September 2004.Results：Pearson correlation coefficients for crude nutrients assessed by FFQ1 and FFQ2 ranged from 0.3l for thiamin to 0.61 for fat(mean of all nutrients 0.46)．Pearson correlation coeffcients for nutrients estimated by FFQ2 and 24-hour recalIs ranged from 0.53 for cholesterol to 0.70 for α-vitamin E and potassium(mean of all nutrients 0.62)．Energy-adjustment lowered most coefficients．De-attenuated&an．adjusted coefficients ranged from 0.58 for cholesterol to 0.77 for α-vitamin E(mean of all nutrients 0.69)．Bland-Altman plots revealed significant relationships between the difference and the average of the two methods with larger differences at higher average intakes．On average，74﹪of participants were classified into the same or adjacent nutrient intake quintiles，while 1﹪were grossly misclassified to opposite quintiles．The same four food groups accounted for 80﹪0f total food energy intake in both methods．Conclusions：This FFQ has adequate reproducibility and validity for most nutrients and is suitable for use to assess dietary intake in pregnant women inrural China．

摘要： Objective：To validate a semi-quantitative fbod-frequency questionnaire(FFQ)for evaluating nutrient intake among pregnant women in rural China．Design：Longitudinal validation study with interview administrated FFQs at start of third trimester(FFQ1)and repeated three months later prior to delivery(FFQ2)，with six repeated 24-hour recalls in between．Setting：Two rural counties in Shaanxi province，western China．Subjects：125 women at 23 to 26 weeks gestation recruited from June to September 2004.Results：Pearson correlation coefficients for crude nutrients assessed by FFQ1 and FFQ2 ranged from 0.3l for thiamin to 0.61 for fat(mean of all nutrients 0.46)．Pearson correlation coeffcients for nutrients estimated by FFQ2 and 24-hour recalIs ranged from 0.53 for cholesterol to 0.70 for α-vitamin E and potassium(mean of all nutrients 0.62)．Energy-adjustment lowered most coefficients．De-attenuated&an．adjusted coefficients ranged from 0.58 for cholesterol to 0.77 for α-vitamin E(mean of all nutrients 0.69)．Bland-Altman plots revealed significant relationships between the difference and the average of the two methods with larger differences at higher average intakes．On average，74﹪of participants were classified into the same or adjacent nutrient intake quintiles，while 1﹪were grossly misclassified to opposite quintiles．The same four food groups accounted for 80﹪0f total food energy intake in both methods．Conclusions：This FFQ has adequate reproducibility and validity for most nutrients and is suitable for use to assess dietary intake in pregnant women inrural China．

摘要： Objective：To validate a semi-quantitative fbod-frequency questionnaire(FFQ)for evaluating nutrient intake among pregnant women in rural China．Design：Longitudinal validation study with interview administrated FFQs at start of third trimester(FFQ1)and repeated three months later prior to delivery(FFQ2)，with six repeated 24-hour recalls in between．Setting：Two rural counties in Shaanxi province，western China．Subjects：125 women at 23 to 26 weeks gestation recruited from June to September 2004.Results：Pearson correlation coefficients for crude nutrients assessed by FFQ1 and FFQ2 ranged from 0.3l for thiamin to 0.61 for fat(mean of all nutrients 0.46)．Pearson correlation coeffcients for nutrients estimated by FFQ2 and 24-hour recalIs ranged from 0.53 for cholesterol to 0.70 for α-vitamin E and potassium(mean of all nutrients 0.62)．Energy-adjustment lowered most coefficients．De-attenuated&an．adjusted coefficients ranged from 0.58 for cholesterol to 0.77 for α-vitamin E(mean of all nutrients 0.69)．Bland-Altman plots revealed significant relationships between the difference and the average of the two methods with larger differences at higher average intakes．On average，74﹪of participants were classified into the same or adjacent nutrient intake quintiles，while 1﹪were grossly misclassified to opposite quintiles．The same four food groups accounted for 80﹪0f total food energy intake in both methods．Conclusions：This FFQ has adequate reproducibility and validity for most nutrients and is suitable for use to assess dietary intake in pregnant women inrural China．

摘要： Objective：To validate a semi-quantitative fbod-frequency questionnaire(FFQ)for evaluating nutrient intake among pregnant women in rural China．Design：Longitudinal validation study with interview administrated FFQs at start of third trimester(FFQ1)and repeated three months later prior to delivery(FFQ2)，with six repeated 24-hour recalls in between．Setting：Two rural counties in Shaanxi province，western China．Subjects：125 women at 23 to 26 weeks gestation recruited from June to September 2004.Results：Pearson correlation coefficients for crude nutrients assessed by FFQ1 and FFQ2 ranged from 0.3l for thiamin to 0.61 for fat(mean of all nutrients 0.46)．Pearson correlation coeffcients for nutrients estimated by FFQ2 and 24-hour recalIs ranged from 0.53 for cholesterol to 0.70 for α-vitamin E and potassium(mean of all nutrients 0.62)．Energy-adjustment lowered most coefficients．De-attenuated&an．adjusted coefficients ranged from 0.58 for cholesterol to 0.77 for α-vitamin E(mean of all nutrients 0.69)．Bland-Altman plots revealed significant relationships between the difference and the average of the two methods with larger differences at higher average intakes．On average，74﹪of participants were classified into the same or adjacent nutrient intake quintiles，while 1﹪were grossly misclassified to opposite quintiles．The same four food groups accounted for 80﹪0f total food energy intake in both methods．Conclusions：This FFQ has adequate reproducibility and validity for most nutrients and is suitable for use to assess dietary intake in pregnant women inrural China．

摘要： Objective：To validate a semi-quantitative fbod-frequency questionnaire(FFQ)for evaluating nutrient intake among pregnant women in rural China．Design：Longitudinal validation study with interview administrated FFQs at start of third trimester(FFQ1)and repeated three months later prior to delivery(FFQ2)，with six repeated 24-hour recalls in between．Setting：Two rural counties in Shaanxi province，western China．Subjects：125 women at 23 to 26 weeks gestation recruited from June to September 2004.Results：Pearson correlation coefficients for crude nutrients assessed by FFQ1 and FFQ2 ranged from 0.3l for thiamin to 0.61 for fat(mean of all nutrients 0.46)．Pearson correlation coeffcients for nutrients estimated by FFQ2 and 24-hour recalIs ranged from 0.53 for cholesterol to 0.70 for α-vitamin E and potassium(mean of all nutrients 0.62)．Energy-adjustment lowered most coefficients．De-attenuated&an．adjusted coefficients ranged from 0.58 for cholesterol to 0.77 for α-vitamin E(mean of all nutrients 0.69)．Bland-Altman plots revealed significant relationships between the difference and the average of the two methods with larger differences at higher average intakes．On average，74﹪of participants were classified into the same or adjacent nutrient intake quintiles，while 1﹪were grossly misclassified to opposite quintiles．The same four food groups accounted for 80﹪0f total food energy intake in both methods．Conclusions：This FFQ has adequate reproducibility and validity for most nutrients and is suitable for use to assess dietary intake in pregnant women inrural China．