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Quantifying the agreement and accuracy characteristics of four satellite-based LULC products for cropland classification in China 被引量:1
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作者 Jie Xue Xianglin Zhang +3 位作者 Songchao Chen Bifeng Hu Nan Wang Zhou Shi 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期283-297,共15页
Various land use and land cover(LULC)products have been produced over the past decade with the development of remote sensing technology.Despite the differences in LULC classification schemes,there is a lack of researc... Various land use and land cover(LULC)products have been produced over the past decade with the development of remote sensing technology.Despite the differences in LULC classification schemes,there is a lack of research on assessing the accuracy of their application to croplands in a unified framework.Thus,this study evaluated the spatial and area accuracies of cropland classification for four commonly used global LULC products(i.e.,MCD12Q1V6,GlobCover2009,FROM-GLC and GlobeLand30)based on the harmonised FAO criterion,and quantified the relationships between four factors(i.e.,slope,elevation,field size and crop system)and cropland classification agreement.The validation results indicated that MCD12Q1 and GlobeLand30 performed well in cropland classification regarding spatial consistency,with overall accuracies of 94.90 and 93.52%,respectively.The FROMGLC showed the worst performance,with an overall accuracy of 83.17%.Overlaying the cropland generated by the four global LULC products,we found the proportions of complete agreement and disagreement were 15.51 and 44.72% for the cropland classification,respectively.High consistency was mainly observed in the Northeast China Plain,the Huang-Huai-Hai Plain and the northern part of the Middle-lower Yangtze Plain,China.In contrast,low consistency was detected primarily on the eastern edge of the northern and semiarid region,the Yunnan-Guizhou Plateau and southern China.Field size was the most important factor for mapping cropland.For area accuracy,compared with China Statistical Yearbook data at the provincial scale,the accuracies of different products in descending order were:GlobeLand30,FROM-GLC,MCD12Q1,and GlobCover2009.The cropland classification schemes mainly caused large area deviations among the four products,and they also resulted in the different ranks of spatial accuracy and area accuracy among the four products.Our results can provide valuable suggestions for selecting cropland products at the national or provincial scale and help cropland mapping and reconstruction,which is essential for food security and crop management,so they can also contribute to achieving the Sustainable Development Goals issued by the United Nations. 展开更多
关键词 global LULC products cropland mapping accuracy evaluation food security China
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Influence of initial check, information exchange, final accuracy check, reaction information nursing on the psychology of elderly with lung cancer 被引量:2
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作者 Cui Jiang Jing Ma +1 位作者 Wen He Hai-Ying Zhang 《World Journal of Clinical Cases》 SCIE 2024年第4期737-745,共9页
BACKGROUND As one of the fatal diseases with high incidence,lung cancer has seriously endangered public health and safety.Elderly patients usually have poor self-care and are more likely to show a series of psychologi... BACKGROUND As one of the fatal diseases with high incidence,lung cancer has seriously endangered public health and safety.Elderly patients usually have poor self-care and are more likely to show a series of psychological problems.AIM To investigate the effectiveness of the initial check,information exchange,final accuracy check,reaction(IIFAR)information care model on the mental health status of elderly patients with lung cancer.METHODS This study is a single-centre study.We randomly recruited 60 elderly patients with lung cancer who attended our hospital from January 2021 to January 2022.These elderly patients with lung cancer were randomly divided into two groups,with the control group taking the conventional propaganda and education and the observation group taking the IIFAR information care model based on the conventional care protocol.The differences in psychological distress,anxiety and depression,life quality,fatigue,and the locus of control in psychology were compared between these two groups,and the causes of psychological distress were analyzed.RESULTS After the intervention,Distress Thermometer,Hospital Anxiety and Depression Scale(HADS)for anxiety and the HADS for depression,Revised Piper’s Fatigue Scale,and Chance Health Locus of Control scores were lower in the observation group compared to the pre-intervention period in the same group and were significantly lower in the observation group compared to those of the control group(P<0.05).After the intervention,Quality of Life Questionnaire Core 30(QLQ-C30),Internal Health Locus of Control,and Powerful Others Health Locus of Control scores were significantly higher in the observation and the control groups compared to the pre-intervention period in their same group,and QLQ-C30 scores were significantly higher in the observation group compared to those of the control group(P<0.05).CONCLUSION The IIFAR information care model can help elderly patients with lung cancer by reducing their anxiety and depression,psychological distress,and fatigue,improving their tendencies on the locus of control in psychology,and enhancing their life qualities. 展开更多
关键词 Initial check information exchange final accuracy check reaction information care model Lung cancer Mental health
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Accuracy of FreeStyle Libre flash glucose monitoring in patients with type 2 diabetes who migrated from highlands to plains 被引量:1
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作者 Zeng-Mei Sun Yuan-Ze Du +11 位作者 Su-Yuan Wang Shu-Yao Sun Yan Ye Xue-Ping Sun Ming-Xia Li Hua He Wun-Chun Long Cheng-Hui Zhang Xuan-Yu Yao Wu-Yi Fan Ling Wang Yun-Hong Wu 《World Journal of Diabetes》 SCIE 2024年第6期1254-1262,共9页
BACKGROUND The FreeStyle Libre flash glucose monitoring(FGM)system entered the Chinese market in 2017 to complement the self-monitoring of blood glucose.Due to its increased usage in clinics,the number of studies inve... BACKGROUND The FreeStyle Libre flash glucose monitoring(FGM)system entered the Chinese market in 2017 to complement the self-monitoring of blood glucose.Due to its increased usage in clinics,the number of studies investigating its accuracy has increased.However,its accuracy has not been investigated in highland populations in China.AIM To evaluate measurements recorded using the FreeStyle Libre FGM system compared with capillary blood glucose measured using the enzyme electrode method in patients with type 2 diabetes(T2D)who had migrated within 3 mo from highlands to plains.METHODS Overall,68 patients with T2D,selected from those who had recently migrated from highlands to plains(within 3 mo),were hospitalized at the Department of Endocrinology from August to October 2017 and underwent continuous glucose monitoring(CGM)with the FreeStyle Libre FGM system for 14 d.Throughout the study period,fingertip capillary blood glucose was measured daily using the enzyme electrode method(Super GL,China),and blood glucose levels were read from the scanning probe during fasting and 2 h after all three meals.Moreover,the time interval between reading the data from the scanning probe and collecting fingertip capillary blood was controlled to<5 min.The accuracy of the FGM system was evaluated according to the CGM guidelines.Subsequently,the factors influencing the mean absolute relative difference(MARD)of this system were analyzed by a multiple linear regression method.RESULTS Pearson’s correlation analysis showed that the fingertip and scanned glucose levels were positively correlated(R=0.86,P=0.00).The aggregated MARD of scanned glucose was 14.28±13.40%.Parker's error analysis showed that 99.30%of the data pairs were located in areas A and B.According to the probe wear time of the FreeStyle Libre FGM system,MARD_(1 d) and MARD_(2-14 d) were 16.55%and 14.35%,respectively(t=1.23,P=0.22).Multiple stepwise regression analysis showed that MARD did not correlate with blood glucose when the largest amplitude of glycemic excursion(LAGE)was<5.80 mmol/L but negatively correlated with blood glucose when the LAGE was≥5.80 mmol/L.CONCLUSION The FreeStyle Libre FGM system has good accuracy in patients with T2D who had recently migrated from highlands to plains.This system might be ideal for avoiding the effects of high hematocrit on blood glucose monitoring in populations that recently migrated to plains.MARD is mainly influenced by glucose levels and fluctuations,and the accuracy of the system is higher when the blood glucose fluctuation is small.In case of higher blood glucose level fluctuations,deviation in the scanned glucose levels is the highest at extremely low blood glucose levels. 展开更多
关键词 Type 2 diabetes Flash glucose monitoring accuracy Continuous glucose monitor High altitude
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Urea breath test for Helicobacter pylori infection in adult dyspeptic patients: A meta-analysis of diagnostic test accuracy
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作者 Fabian Fellipe Bueno Lemos Caroline Tianeze de Castro +9 位作者 Marcel Silva Luz Gabriel Reis Rocha Gabriel Lima Correa Santos Luís Guilherme de Oliveira Silva Mariana Santos Calmon Cláudio Lima Souza Ana Carla Zarpelon-Schutz Kádima Nayara Teixeira Dulciene Maria de Magalhães Queiroz Fabrício Freire de Melo 《World Journal of Gastroenterology》 SCIE CAS 2024年第6期579-598,共20页
BACKGROUND Helicobacter pylori(H.pylori)infection has been well-established as a significant risk factor for several gastrointestinal disorders.The urea breath test(UBT)has emerged as a leading non-invasive method for... BACKGROUND Helicobacter pylori(H.pylori)infection has been well-established as a significant risk factor for several gastrointestinal disorders.The urea breath test(UBT)has emerged as a leading non-invasive method for detecting H.pylori.Despite numerous studies confirming its substantial accuracy,the reliability of UBT results is often compromised by inherent limitations.These findings underscore the need for a rigorous statistical synthesis to clarify and reconcile the diagnostic accuracy of the UBT for the diagnosis of H.pylori infection.AIM To determine and compare the diagnostic accuracy of 13C-UBT and 14C-UBT for H.pylori infection in adult patients with dyspepsia.METHODS We conducted an independent search of the PubMed/MEDLINE,EMBASE,and Cochrane Central databases until April 2022.Our search included diagnostic accuracy studies that evaluated at least one of the index tests(^(13)C-UBT or ^(14)C-UBT)against a reference standard.We used the QUADAS-2 tool to assess the methodo-logical quality of the studies.We utilized the bivariate random-effects model to calculate sensitivity,specificity,positive and negative test likelihood ratios(LR+and LR-),as well as the diagnostic odds ratio(DOR),and their 95%confidence intervals.We conducted subgroup analyses based on urea dosing,time after urea administration,and assessment technique.To investigate a possible threshold effect,we conducted Spearman correlation analysis,and we generated summary receiver operating characteristic(SROC)curves to assess heterogeneity.Finally,we visually inspected a funnel plot and used Egger’s test to evaluate publication bias.endorsing both as reliable diagnostic tools in clinical practice.CONCLUSION In summary,our study has demonstrated that ^(13)C-UBT has been found to outperform the ^(14)C-UBT,making it the preferred diagnostic approach.Additionally,our results emphasize the significance of carefully considering urea dosage,assessment timing,and measurement techniques for both tests to enhance diagnostic precision.Nevertheless,it is crucial for researchers and clinicians to evaluate the strengths and limitations of our findings before implementing them in practice. 展开更多
关键词 Helicobacter pylori Urea breath test DIAGNOSIS Diagnostic test accuracy META-ANALYSIS
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Accuracy assessment of global vertical displacement loading tide models for the equatorial and Indian Ocean
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作者 Xiaoqing Xu Haidong Pan +1 位作者 Fei Teng Zexun Wei 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第9期11-25,共15页
The three-dimensional displacements caused by ocean loading effects are significant enough to impact spatial geodetic measurements on sub-daily or longer timescales,particularly in the vertical direction.Currently,mos... The three-dimensional displacements caused by ocean loading effects are significant enough to impact spatial geodetic measurements on sub-daily or longer timescales,particularly in the vertical direction.Currently,most tide models incorporate the distribution of vertical displacement loading tides;however,their accuracy has not been assessed for the equatorial and Indian Ocean regions.Global Positioning System(GPS)observations provide high-precision data on sea-level changes,enabling the assessment of the accuracy and reliability of vertical displacement tide models.However,because the tidal period of the K_(2) constituent is almost identical to the orbital period of GPS constellations,the estimation of the K_(2) tidal constituent from GPS observations is not satisfactory.In this study,the principle of smoothness is employed to correct the systematic error in K_(2) estimates in GPS observations through quadratic fitting.Using the adjusted harmonic constants from 31 GPS stations for the equatorial and Indian Ocean,the accuracy of eight major constituents from five global vertical displacement tide models(FES2014,EOT11a,GOT4.10c,GOT4.8,and NAO.99b)is evaluated for the equatorial and Indian Ocean.The results indicate that the EOT11a and FES2014 models exhibit higher accuracy in the vertical displacement tide models for the equatorial and Indian Ocean,with root sum squares errors of 2.29 mm and 2.34 mm,res-pectively.Furthermore,a brief analysis of the vertical displacement tide distribution characteristics of the eight major constituents for the equatorial and Indian Ocean was conducted using the EOT11a model. 展开更多
关键词 accuracy assessment vertical displacement loading tide models tidal admittance equatorial and Indian Ocean GPS constellation
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Diagnostic Accuracy of Computerized Bowel Sound Analysis with Non-Invasive Devices for Irritable Bowel Syndrome:A Systematic Review and Meta-Analysis
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作者 Xia-Xiao Yan Yue-Lun Zhang +2 位作者 Yu-Pei Zhang Ying-Yun Yang Dong Wu 《Chinese Medical Sciences Journal》 CAS CSCD 2024年第2期122-130,共9页
Objective To assess the diagnostic accuracy of bowel sound analysis for irritable bowel syndrome(IBS)with a systematic review and meta-analysis.Methods We searched MEDLINE,Embase,the Cochrane Library,Web of Science,an... Objective To assess the diagnostic accuracy of bowel sound analysis for irritable bowel syndrome(IBS)with a systematic review and meta-analysis.Methods We searched MEDLINE,Embase,the Cochrane Library,Web of Science,and IEEE Xplore databases until September 2023.Cross-sectional and case-control studies on diagnostic accuracy of bowel sound analysis for IBS were identified.We estimated the pooled sensitivity,specificity,positive likelihood ratio,negative likeli-hood ratio,and diagnostic odds ratio with a 95% confidence interval(CI),and plotted a summary receiver operat-ing characteristic curve and evaluated the area under the curve.Results Four studies were included.The pooled diagnostic sensitivity,specificity,positive likelihood ratio,nega-tive likelihood ratio,and diagnostic odds ratio were 0.94(95%CI,0.87‒0.97),0.89(95%CI,0.81‒0.94),8.43(95%CI,4.81‒14.78),0.07(95%CI,0.03‒0.15),and 118.86(95%CI,44.18‒319.75),respectively,with an area under the curve of 0.97(95%CI,0.95‒0.98).Conclusions Computerized bowel sound analysis is a promising tool for IBS.However,limited high-quality data make the results'validity and applicability questionable.There is a need for more diagnostic test accuracy studies and better wearable devices for monitoring and analysis of IBS. 展开更多
关键词 irritable bowel syndrome bowel sound analysis diagnostic accuracy systematic review META-ANALYSIS
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Hyper accuracy three-dimensional virtual anatomical rainbow model facilitates surgical planning and safe selective clamping during robot-assisted partial nephrectomy
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作者 Francesco Ditonno Antonio Franco +8 位作者 Celeste Manfredi Daniele Amparore Enrico Checcucci Marco De Sio Alessandro Antonelli Cosimo De Nunzio Cristian Fiori Francesco Porpiglia Riccardo Autorino 《Asian Journal of Urology》 CSCD 2024年第4期660-665,共6页
ObjectiveTo highlight the role of hyper accuracy three-dimensional(3D)reconstruction in facilitating surgical planning and guiding selective clamping during robot-assisted partial nephrectomy(RAPN).MethodsA transperit... ObjectiveTo highlight the role of hyper accuracy three-dimensional(3D)reconstruction in facilitating surgical planning and guiding selective clamping during robot-assisted partial nephrectomy(RAPN).MethodsA transperitoneal RAPN was performed in a 62-year-old male patient presenting with a 4 cm right anterior interpolar renal mass(R.E.N.A.L nephrometry score 7A).An abnormal vasculature was observed,with a single renal vein and two right renal arteries originating superiorly to the vein and anterior,when dividing in their segmental branches.According to the hyper accuracy 3D(HA3D^(®))rainbow model(MEDICS Srl,Turin,Italy),one branch belonging to one of the segmental arteries was feeding the tumor.This allowed for an accurate prediction of the area vascularized by each arterial branch.The 3D model was included in the intraoperative console view during the whole procedure,using the TilePro feature.A step-by-step explanation of the procedure is provided in the video attached to the present article.ResultsThe operative time was 90 min with a warm ischemia time on selective clamping of 13 min.Estimated blood loss was 180 mL.No intraoperative complication was encountered and no drain was placed at the end of the procedure.The patient was discharged on postoperative Day 2,without any early postoperative complications.The final pathology report showed a pathological tumor stage 1 clear cell renal cell carcinoma with negative surgical margins.ConclusionThe present study and the attached video illustrate the value of 3D rainbow model during the planning and execution of a RAPN with selective clamping.It shows how the surgeon can rely on this model to be more efficient by avoiding unnecessary surgical steps,and to safely adopt a“selective”clamping strategy that can translate in minimal functional impact. 展开更多
关键词 Hyper accuracy three-dimensional rainbow model Augmented reality Clear cell renal cell carcinoma Robot-assisted partial nephrectomy Selective clamping
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Clinical study on improving the diagnostic accuracy of adult elbow joint cartilage injury by multisequence magnetic resonance imaging
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作者 Wei-Wei Ding Lei Ding +6 位作者 Li Li Pan Zhang Rui Gong Jian Li Meng-Ying Xu Feng Ding Bing Chen 《World Journal of Clinical Cases》 SCIE 2024年第25期5673-5680,共8页
BACKGROUND Due to frequent and high-risk sports activities,the elbow joint is susceptible to injury,especially to cartilage tissue,which can cause pain,limited movement and even loss of joint function.AIM To evaluate ... BACKGROUND Due to frequent and high-risk sports activities,the elbow joint is susceptible to injury,especially to cartilage tissue,which can cause pain,limited movement and even loss of joint function.AIM To evaluate magnetic resonance imaging(MRI)multisequence imaging for improving the diagnostic accuracy of adult elbow cartilage injury.METHODS A total of 60 patients diagnosed with elbow cartilage injury in our hospital from January 2020 to December 2021 were enrolled in this retrospective study.We analyzed the accuracy of conventional MRI sequences(T1-weighted imaging,T2-weighted imaging,proton density weighted imaging,and T2 star weighted image)and Three-Dimensional Coronary Imaging by Spiral Scanning(3D-CISS)in the diagnosis of elbow cartilage injury.Arthroscopy was used as the gold standard to evaluate the diagnostic effect of single and combination sequences in different injury degrees and the consistency with arthroscopy.RESULTS The diagnostic accuracy of 3D-CISS sequence was 89.34%±4.98%,the sensitivity was 90%,and the specificity was 88.33%,which showed the best performance among all sequences(P<0.05).The combined application of the whole sequence had the highest accuracy in all sequence combinations,the accuracy of mild injury was 91.30%,the accuracy of moderate injury was 96.15%,and the accuracy of severe injury was 93.33%(P<0.05).Compared with arthroscopy,the combination of all MRI sequences had the highest consistency of 91.67%,and the kappa value reached 0.890(P<0.001).CONCLUSION Combination of 3D-CISS and each sequence had significant advantages in improving MRI diagnostic accuracy of elbow cartilage injuries in adults.Multisequence MRI is recommended to ensure the best diagnosis and treatment. 展开更多
关键词 MRI multisequence imaging Cartilage injury of elbow joint accuracy of diagnosis ARTHROSCOPY 3D-CISS
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Numerical Investigation of Thermal Behavior of CNC Machine Tool and Its Effects on Dimensional Accuracy of Machined Parts
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作者 Erick Matezo-Ngoma Abderrazak El Ouafi Ahmed Chebak 《Journal of Software Engineering and Applications》 2024年第8期617-637,共21页
The dimensional accuracy of machined parts is strongly influenced by the thermal behavior of machine tools (MT). Minimizing this influence represents a key objective for any modern manufacturing industry. Thermally in... The dimensional accuracy of machined parts is strongly influenced by the thermal behavior of machine tools (MT). Minimizing this influence represents a key objective for any modern manufacturing industry. Thermally induced positioning error compensation remains the most effective and practical method in this context. However, the efficiency of the compensation process depends on the quality of the model used to predict the thermal errors. The model should consistently reflect the relationships between temperature distribution in the MT structure and thermally induced positioning errors. A judicious choice of the number and location of temperature sensitive points to represent heat distribution is a key factor for robust thermal error modeling. Therefore, in this paper, the temperature sensitive points are selected following a structured thermomechanical analysis carried out to evaluate the effects of various temperature gradients on MT structure deformation intensity. The MT thermal behavior is first modeled using finite element method and validated by various experimentally measured temperature fields using temperature sensors and thermal imaging. MT Thermal behavior validation shows a maximum error of less than 10% when comparing the numerical estimations with the experimental results even under changing operation conditions. The numerical model is used through several series of simulations carried out using varied working condition to explore possible relationships between temperature distribution and thermal deformation characteristics to select the most appropriate temperature sensitive points that will be considered for building an empirical prediction model for thermal errors as function of MT thermal state. Validation tests achieved using an artificial neural network based simplified model confirmed the efficiency of the proposed temperature sensitive points allowing the prediction of the thermally induced errors with an accuracy greater than 90%. 展开更多
关键词 CNC Machine Tool Dimensional accuracy Thermal Errors Error Modelling Numerical Simulation Finite Element Method Artificial Neural Network Error Compensation
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Further Analysis of Machine Tool Dimensional Accuracy and Thermal Stability under Varying Floor Temperature
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作者 Joel Arumun Shadrack Abiola 《World Journal of Engineering and Technology》 2024年第2期258-273,共16页
Machining is as old as humanity, and changes in temperature in both the machine’s internal and external environments can be of great concern as they affect the machine’s thermal stability and, thus, the machine’s d... Machining is as old as humanity, and changes in temperature in both the machine’s internal and external environments can be of great concern as they affect the machine’s thermal stability and, thus, the machine’s dimensional accuracy. This paper is a continuation of our earlier work, which aimed to analyze the effect of the internal temperature of a machine tool as the machine is put into operation and vary the external temperature, the machine floor temperature. Some experiments are carried out under controlled conditions to study how machine tool components get heated up and how this heating up affects the machine’s accuracy due to thermally induced deviations. Additionally, another angle is added by varying the machine floor temperature. The parameters mentioned above are explored in line with the overall thermal stability of the machine tool and its dimensional accuracy. A Robodrill CNC machine tool is used. The CNC was first soaked with thermal energy by gradually raising the machine floor temperature to a certain level before putting the machine in operation. The machine was monitored, and analytical methods were deplored to evaluate thermal stability. Secondly, the machine was run idle for some time under raised floor temperature before it was put into operation. Data was also collected and analyzed. It is observed that machine thermal stability can be achieved in several ways depending on how the above parameters are joggled. This paper, in conclusion, reinforces the idea of machine tool warm-up process in conjunction with a carefully analyzed and established machine floor temperature variation for the approximation of the machine tool’s thermally stability to map the long-time behavior of the machine tool. 展开更多
关键词 Dimensional accuracy Machine Tool Machine Floor Thermal Stability TEMPERATURE Thermal Deviation
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Study on the Accuracy of Serum Prealbumin Level in Predicting the Prognosis of Patients with Critical Respiratory Illness
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作者 Xiang Wang Zuozhou Xie +1 位作者 Jinhong Zhao Yi Liu 《Journal of Clinical and Nursing Research》 2024年第3期89-94,共6页
Objective: To analyze the accuracy of serum prealbumin levels in predicting the prognosis of patients with critical respiratory illness. Methods: Fifty patients with critical respiratory illness admitted to our hospit... Objective: To analyze the accuracy of serum prealbumin levels in predicting the prognosis of patients with critical respiratory illness. Methods: Fifty patients with critical respiratory illness admitted to our hospital from October 2022 to September 2023 were selected and divided into an observation group and a control group after condition assessment, with 25 cases in each group. The results of cholinesterase (ChE), prealbumin (PALB), albumin (ALB), aspartate aminotransferase (AST), total protein (TP), and forced expiratory volume (FEV1)/Predicted (Pred) of the two groups were measured. Results: The ChE levels of the observation group were lower than those of the control group, while the PALB and ALB levels of the observation group were higher than those of the control group (P < 0.05). The AST, TP, and FEV1 /Pred levels of the observation group were higher than those in the control group (P < 0.05). Conclusion: Serum PALB levels can be used as the main indicator for prognosis in critically ill respiratory patients. 展开更多
关键词 Serum prealbumin Respiratory critical illness Prognostic level accuracy
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Fusion of Activation Functions: An Alternative to Improving Prediction Accuracy in Artificial Neural Networks
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作者 Justice Awosonviri Akodia Clement K. Dzidonu +1 位作者 David King Boison Philip Kisembe 《World Journal of Engineering and Technology》 2024年第4期836-850,共15页
The purpose of this study was to address the challenges in predicting and classifying accuracy in modeling Container Dwell Time (CDT) using Artificial Neural Networks (ANN). This objective was driven by the suboptimal... The purpose of this study was to address the challenges in predicting and classifying accuracy in modeling Container Dwell Time (CDT) using Artificial Neural Networks (ANN). This objective was driven by the suboptimal outcomes reported in previous studies and sought to apply an innovative approach to improve these results. To achieve this, the study applied the Fusion of Activation Functions (FAFs) to a substantial dataset. This dataset included 307,594 container records from the Port of Tema from 2014 to 2022, encompassing both import and transit containers. The RandomizedSearchCV algorithm from Python’s Scikit-learn library was utilized in the methodological approach to yield the optimal activation function for prediction accuracy. The results indicated that “ajaLT”, a fusion of the Logistic and Hyperbolic Tangent Activation Functions, provided the best prediction accuracy, reaching a high of 82%. Despite these encouraging findings, it’s crucial to recognize the study’s limitations. While Fusion of Activation Functions is a promising method, further evaluation is necessary across different container types and port operations to ascertain the broader applicability and generalizability of these findings. The original value of this study lies in its innovative application of FAFs to CDT. Unlike previous studies, this research evaluates the method based on prediction accuracy rather than training time. It opens new avenues for machine learning engineers and researchers in applying FAFs to enhance prediction accuracy in CDT modeling, contributing to a previously underexplored area. 展开更多
关键词 Artificial Neural Networks Container Dwell Time Fusion of Activation Functions Randomized Search CV Algorithm Prediction accuracy
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Machine acceleration time series prediction for dimensional accuracy of 3D printed parts
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作者 Jayanta Bhusan Deb Shilpa Chowdhury +4 位作者 Soumik Chowdhury Gourab Paul Tonay Pal Jayeeta Deb Sudipta Deb 《Data Science and Management》 2024年第3期218-227,共10页
This study explores the influence of infill patterns on machine acceleration prediction in the realm of three-dimensional(3D)printing,particularly focusing on extrusion technology.Our primary objective was to develop ... This study explores the influence of infill patterns on machine acceleration prediction in the realm of three-dimensional(3D)printing,particularly focusing on extrusion technology.Our primary objective was to develop a long short-term memory(LSTM)network capable of assessing this impact.We conducted an extensive analysis involving 12 distinct infill patterns,collecting time-series data to examine their effects on the acceleration of the printer’s bed.The LSTM network was trained using acceleration data from the adaptive cubic infill pattern,while the Archimedean chords infill pattern provided data for evaluating the network’s prediction accuracy.This involved utilizing offline time-series acceleration data as the training and testing datasets for the LSTM model.Specifically,the LSTM model was devised to predict the acceleration of a fused deposition modeling(FDM)printer using data from the adaptive cubic infill pattern.Rigorous testing yielded a root mean square error(RMSE)of 0.007144,reflecting the model’s precision.Further refinement and testing of the LSTM model were conducted using acceleration data from the Archimedean chords infill pattern,resulting in an RMSE of 0.007328.Notably,the developed LSTM model demonstrated superior performance compared to an optimized recurrent neural network(RNN)in predicting machine acceleration data.The empirical findings highlight that the adaptive cubic infill pattern considerably influences the dimensional accuracy of parts printed using FDM technology. 展开更多
关键词 Extrusion-based 3D printing Printer acceleration predictionInfill pattern Root mean square error Dimensional accuracy
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Calibration of a Confidence Interval for a Classification Accuracy
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作者 Steen Magnussen 《Open Journal of Forestry》 2021年第1期14-36,共23页
Coverage of nominal 95% confidence intervals of a proportion estimated from a sample obtained under a complex survey design, or a proportion estimated from a ratio of two random variables, can depart significantly fro... Coverage of nominal 95% confidence intervals of a proportion estimated from a sample obtained under a complex survey design, or a proportion estimated from a ratio of two random variables, can depart significantly from its target. Effective calibration methods exist for intervals for a proportion derived from a single binary study variable, but not for estimates of thematic classification accuracy. To promote a calibration of confidence intervals within the context of land-cover mapping, this study first illustrates a common problem of under and over-coverage with standard confidence intervals, and then proposes a simple and fast calibration that more often than not will improve coverage. The demonstration is with simulated sampling from a classified map with four classes, and a reference class known for every unit in a population of 160,000 units arranged in a square array. The simulations include four common probability sampling designs for accuracy assessment, and three sample sizes. Statistically significant over- and under-coverage was present in estimates of user’s (UA) and producer’s accuracy (PA) as well as in estimates of class area proportion. A calibration with Bayes intervals for UA and PA was most efficient with smaller sample sizes and two cluster sampling designs. 展开更多
关键词 Overall accuracy Producer’s accuracy User’s accuracy Area Proportions Semi-Systematic Sampling POST-STRATIFICATION Stratified Random Sampling One-Stage Cluster Sampling Two-Stage Cluster Sampling
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EFFECT OF TOOL-PATH ON MILLING ACCURACY UNDER CLAMPING 被引量:5
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作者 郭魂 左敦稳 +2 位作者 王树宏 徐礼林 王珉 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2005年第3期234-239,共6页
To resolve the deformation problem for thin-walled aero-parts in the actual production, this paper simulates the effect of the tool-path on the machining accuracy of the thin-walled frame. The frame is shaped in the p... To resolve the deformation problem for thin-walled aero-parts in the actual production, this paper simulates the effect of the tool-path on the machining accuracy of the thin-walled frame. The frame is shaped in the part milling under a given clamping condition by using the three-dimensional finite element method (FEM). Result shows that the sidewall deformation has a big difference if only the tool-path changes. When the tool-path from the outside to the inside is used, the machining deformation is smaller than another three kinds of toolpaths. Simulation results are compared with experimental data, and the correctness of the simulation is verified.Reasonable processing paths can be found by FEM. 展开更多
关键词 finite element method tool-path machining accuracy DEFORMATION
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Accuracy profile理论在高效液相色谱法测定纺织品中3种有机溶剂残留中的应用 被引量:2
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作者 保琦蓓 傅科杰 +1 位作者 钱丹 任清庆 《理化检验(化学分册)》 CAS CSCD 北大核心 2017年第3期309-314,共6页
样品经超纯水机械振荡萃取,提取液在Spursil C_(18)色谱柱上分离,以甲醇-水-乙腈(25+70+5)混合液为流动相进行洗脱,检测波长为200nm。N,N-二甲基甲酰胺、N,N-二甲基乙酰胺和N-甲基吡咯烷酮的质量浓度在0.5~10 mg·L^(-1)内与峰面积... 样品经超纯水机械振荡萃取,提取液在Spursil C_(18)色谱柱上分离,以甲醇-水-乙腈(25+70+5)混合液为流动相进行洗脱,检测波长为200nm。N,N-二甲基甲酰胺、N,N-二甲基乙酰胺和N-甲基吡咯烷酮的质量浓度在0.5~10 mg·L^(-1)内与峰面积呈线性关系,检出限(3S/N)为1.1~2.8mg·kg^(-1),测定下限(10S/N)为3.7~9.3mg·kg^(-1)。采用Accuracy profile理论验证方法的准确性,并评估了测定的不确定度,说明方法可满足3种有机溶剂的日常检测要求。 展开更多
关键词 高效液相色谱法 accuracy profile理论 N-甲基吡咯烷酮 N N-二甲基甲酰胺
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An Explicit Difference Scheme with High Accuracy and Branching Stability for Solving Parabolic Partial Differential Equation 被引量:4
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作者 马明书 王肖凤 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第4期98-103,共6页
This paper presents an explicit difference scheme with accuracy and branching stability for solving onedimensional parabolic type equation by the method of undetermined parameters and its truncation error is O(△t4+△... This paper presents an explicit difference scheme with accuracy and branching stability for solving onedimensional parabolic type equation by the method of undetermined parameters and its truncation error is O(△t4+△x4). The stability condition is r=a△t/△x2<1/2. 展开更多
关键词 parabolic type equation explicit difference scheme high accuracy branching stability truncation er
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A Family of High_order Accuracy Explicit Difference Schemes for Solving 2-D Parabolic Partial Differential Equation 被引量:4
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作者 任宗修 陈贞忠 王肖凤 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第3期57-61,共5页
A family of high_order accuracy explicit difference schemes for solving 2_dimension parabolic P.D.E. are constructed. Th e stability condition is r=Δt/Δx 2=Δt/Δy 2【1/2 and the truncation err or is O(Δt 3+Δx... A family of high_order accuracy explicit difference schemes for solving 2_dimension parabolic P.D.E. are constructed. Th e stability condition is r=Δt/Δx 2=Δt/Δy 2【1/2 and the truncation err or is O(Δt 3+Δx 4). 展开更多
关键词 D parabolic P.D.E high_order accuracy explic it difference scheme
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Finite-difference numerical modeling with even-order accuracy in two-phase anisotropic media 被引量:4
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作者 刘洋 魏修 《Applied Geophysics》 SCIE CSCD 2008年第2期107-114,共8页
To improve the accuracy of the conventional finite-difference method, finitedifference numerical modeling methods of any even-order accuracy are recommended. We introduce any even-order accuracy difference schemes of ... To improve the accuracy of the conventional finite-difference method, finitedifference numerical modeling methods of any even-order accuracy are recommended. We introduce any even-order accuracy difference schemes of any-order derivatives derived from Taylor series expansion. Then, a finite-difference numerical modeling method with any evenorder accuracy is utilized to simulate seismic wave propagation in two-phase anisotropic media. Results indicate that modeling accuracy improves with the increase of difference accuracy order number. It is essential to find the optimal order number, grid size, and time step to balance modeling precision and computational complexity. Four kinds of waves, static mode in the source point, SV wave cusps, reflection and transmission waves are observed in two-phase anisotropic media through modeling. 展开更多
关键词 two-phase anisotropy FINITE-DIFFERENCE any even-order accuracy numerical modeling wave equations
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IMPROVEMENT OF DIMENSIONAL ACCURACY FOR GOLD MICROPART PREPARED BY UV-LIGA
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作者 曲宁松 苏兴 +1 位作者 李寒松 曾永彬 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第4期325-330,共6页
The swelling of SU-8 mold is one of the most important factors influencing the dimensional accuracy of a metal mieropart produced by ultra-violet lithography galvanik abformung(UV-LIGA). The isolation belt struc- tu... The swelling of SU-8 mold is one of the most important factors influencing the dimensional accuracy of a metal mieropart produced by ultra-violet lithography galvanik abformung(UV-LIGA). The isolation belt struc- ture is usually employed to enhance the dimensional accuracy of electroformed metal mieropart. However, noble metal is wasted because the isolation belt is filled with metal when noble metal mieroparts are fabricated. There- fore, a semi-isolation belt structure is presented to save noble metal. Furthermore, a high current density is also introduced to shorten the eleetroforming time, and thus the dimensional accuracy of electroformed gold micropart is improved by using the electrolyte jet. The experimental results indicate that both the semi-isolation belt and the high current density can help to enhance the dimensional accuracy of electroformed gold micropart. Its dimen- sional error is only 5 μm at the current density of 0. 6 A/dm2 while the semi-isolation belt structure is used. 展开更多
关键词 ultra-violet lithography galvanik abformung (UV-LIGA) microelectroforming micropart dimen- sional accuracy swelling of SU-8 structure
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