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采用B1-corrected variable-flip-angle(VFA)的定量动态增强MRI在乳腺良恶性病变的研究` 被引量:1
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作者 蒋辉 曲金荣 +3 位作者 宋颖 王立峰 刘翠翠 张宏凯 《中国CT和MRI杂志》 2024年第1期85-87,共3页
目的探讨采用B1-corrected VFA技术的定量动态增强(Dynamic Contrast Enhancement,DCE)MRI在乳腺良恶性鉴别诊断中的价值。方法前瞻性研究本院63例乳腺疾病患者,行3.0 T DCE-MR检查,结合B1-corrected VFA技术获得T1值,在此基础上计算出D... 目的探讨采用B1-corrected VFA技术的定量动态增强(Dynamic Contrast Enhancement,DCE)MRI在乳腺良恶性鉴别诊断中的价值。方法前瞻性研究本院63例乳腺疾病患者,行3.0 T DCE-MR检查,结合B1-corrected VFA技术获得T1值,在此基础上计算出DCE-MRI定量参数:容量转移常数(Ktrans)、速率常数(Kep)和血管外细胞外间隙容积比(Ve),对乳腺恶性、良性及正常腺体组获得的定量参数行Kruskal-Wallis检验;最后绘制ROC(receiver operating characteristic curve,ROC)曲线。结果恶性肿瘤组Ktrans、Kep、Ve中位数(最小值最大值)分别为0.010(0.0010.118)min-1、0.145(0.0020.863)min-1、0.058(0.0020.611);良性病变组Ktrans、Kep、Ve中位数为0.238(0.0090.740)min-1、0.365(0.0201.012)min-1、0.517(01810.923);正常腺体组Ktrans、Kep、Ve中位数为0.812(0.1212.352)min-1、1.147(0.3282.363)min-1、0.712(0.4041.183)。Kruskal-Wallis检验显示三组间Ktrans、Kep、Ve P<0.05,均有统计学意义;良恶性组间、恶性与正常组间的Ktrans、Kep、Ve差异有统计学意义,而良性和正常组之间的Ve值无统计学意义。三者AUC分别为0.875、0.957、0.707,三者判断乳腺良恶性变的Ktrans、Kep、Ve敏感度分别为93.8%、97.9%、45.8%;特异度分别为66.7%、86.73%、86.7%。结论结合B1-corrected VFA序列测量的3.0T DCE-MRI参数Ktrans、Kep、Ve可以反映乳腺良恶性病变的血流灌注特征,可用于乳腺病变良恶性的鉴别诊断。 展开更多
关键词 乳腺 B1-corrected VFA 动态增强磁共振成像
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Thermodynamics in a quantum corrected Reissner-Nordstr?m-AdS black hole and its GUP-corrections
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作者 宋建君 刘成周 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期345-353,共9页
We calculate the thermodynamic quantities in the quantum corrected Reissner-Nordstr?m-AdS(RN-AdS)black hole,and examine their quantum corrections.By analyzing the mass and heat capacity,we give the critical state and ... We calculate the thermodynamic quantities in the quantum corrected Reissner-Nordstr?m-AdS(RN-AdS)black hole,and examine their quantum corrections.By analyzing the mass and heat capacity,we give the critical state and the remnant state,respectively,and discuss their consistency.Then,we investigate the quantum tunneling from the event horizon of massless scalar particle by using the null geodesic method,and charged massive boson W^(±)and fermions by using the Hamilton-Jacob method.It is shown that the same Hawking temperature can be obtained from these tunneling processes of different particles and methods.Next,by using the generalized uncertainty principle(GUP),we study the quantum corrections to the tunneling and the temperature.Then the logarithmic correction to the black hole entropy is obtained. 展开更多
关键词 black hole thermodynamics quantum corrections quantum tunneling generalized uncertainty principle
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Assessing the Performance of a Dynamical Downscaling Simulation Driven by a Bias-Corrected CMIP6 Dataset for Asian Climate
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作者 Zhongfeng XU Ying HAN +4 位作者 Meng-Zhuo ZHANG Chi-Yung TAM Zong-Liang YANG Ahmed M.EL KENAWY Congbin FU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期974-988,共15页
In this study,we aim to assess dynamical downscaling simulations by utilizing a novel bias-corrected global climate model(GCM)data to drive a regional climate model(RCM)over the Asia-western North Pacific region.Three... In this study,we aim to assess dynamical downscaling simulations by utilizing a novel bias-corrected global climate model(GCM)data to drive a regional climate model(RCM)over the Asia-western North Pacific region.Three simulations were conducted with a 25-km grid spacing for the period 1980–2014.The first simulation(WRF_ERA5)was driven by the European Centre for Medium-Range Weather Forecasts Reanalysis 5(ERA5)dataset and served as the validation dataset.The original GCM dataset(MPI-ESM1-2-HR model)was used to drive the second simulation(WRF_GCM),while the third simulation(WRF_GCMbc)was driven by the bias-corrected GCM dataset.The bias-corrected GCM data has an ERA5-based mean and interannual variance and long-term trends derived from the ensemble mean of 18 CMIP6 models.Results demonstrate that the WRF_GCMbc significantly reduced the root-mean-square errors(RMSEs)of the climatological mean of downscaled variables,including temperature,precipitation,snow,wind,relative humidity,and planetary boundary layer height by 50%–90%compared to the WRF_GCM.Similarly,the RMSEs of interannual-tointerdecadal variances of downscaled variables were reduced by 30%–60%.Furthermore,the WRF_GCMbc better captured the annual cycle of the monsoon circulation and intraseasonal and day-to-day variabilities.The leading empirical orthogonal function(EOF)shows a monopole precipitation mode in the WRF_GCM.In contrast,the WRF_GCMbc successfully reproduced the observed tri-pole mode of summer precipitation over eastern China.This improvement could be attributed to a better-simulated location of the western North Pacific subtropical high in the WRF_GCMbc after GCM bias correction. 展开更多
关键词 bias correction multi-model ensemble mean dynamical downscaling interannual variability day-to-day variability validation
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Assessment of corrected time-step method for nominal ionospheric gradient calculation: A comparative analysis with spatial approaches
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作者 Slamet Supriadi Prayitno Abadi +4 位作者 Susumu Saito Harry Bangkit Dwiko Unggul Prabowo Adi Purwono Ginaldi Ari Nugroho 《Earth and Planetary Physics》 EI CAS CSCD 2024年第4期641-649,共9页
The effect of ionospheric delay on the ground-based augmentation system under normal conditions can be mitigated by determining the value of the nominal ionospheric gradient(σvig).The nominal ionospheric gradient is ... The effect of ionospheric delay on the ground-based augmentation system under normal conditions can be mitigated by determining the value of the nominal ionospheric gradient(σvig).The nominal ionospheric gradient is generally obtained from Continuously Operating Reference Stations data by using the spatial single-difference method(mixed-pair,station-pair,or satellite-pair)or the temporal single-difference method(time-step).The time-step method uses only a single receiver,but it still contains ionospheric temporal variations.We introduce a corrected time-step method using a fixed-ionospheric pierce point from the geostationary equatorial orbit satellite and test it through simulations based on the global ionospheric model.We also investigate the effect of satellite paths on the corrected time-step method in the region of the equator,which tends to be in a more north–south direction and to have less coverage for the east–west ionospheric gradient.This study also addresses the limitations of temporal variation correction coverage and recommends using only the correction from self-observations.All processes are developed under simulations because observational data are still difficult to obtain.Our findings demonstrate that the corrected time-step method yieldsσvig values consistent with other approaches. 展开更多
关键词 ground-based augmentation system nominal ionospheric gradient time-step correction global ionospheric model
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Corrected QT interval in cirrhosis:A systematic review and metaanalysis 被引量:1
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作者 Vasileios Periklis Papadopoulos Konstantinos Mimidis 《World Journal of Hepatology》 2023年第9期1060-1083,共24页
BACKGROUND Corrected QT(QTc)interval is prolonged in patients with liver cirrhosis and has been proposed to correlate with the severity of the disease.However,the effects of sex,age,severity,and etiology of cirrhosis ... BACKGROUND Corrected QT(QTc)interval is prolonged in patients with liver cirrhosis and has been proposed to correlate with the severity of the disease.However,the effects of sex,age,severity,and etiology of cirrhosis on QTc have not been elucidated.At the same time,the role of treatment,acute illness,and liver transplantation(Tx)remains largely unknown.AIM To determine the mean QTc in patients with cirrhosis,assess whether QTc is prolonged in patients with cirrhosis,and investigate whether QTc is affected by factors such as sex,age,severity,etiology,treatment,acute illness,and liver Tx.METHODS In the present systematic review and meta-analysis,the searching protocol“{[QTc]OR[QT interval]OR[QT-interval]OR[Q-T syndrome]}AND{[cirrhosis]OR[Child-Pugh]OR[MELD]}”was applied in PubMed,EMBASE,and Google Scholar databases to identify studies that reported QTc in patients with cirrhosis and published after 1998.Seventy-three studies were considered eligible.Data concerning first author,year of publication,type of study,method used,sample size,mean age,female ratio,alcoholic etiology of cirrhosis ratio,Child-Pugh A/B/C ratio,mean model for end-stage liver disease(MELD)score,treatment withβ-blockers,episode of acute gastrointestinal bleeding,formula for QT correction,mean pulse rate,QTc in patients with cirrhosis and controls,and QTc according to etiology of cirrhosis,sex,Child-Pugh stage,MELD score,and liver Tx status(pre-Tx/post-Tx)were retrieved.The Newcastle-Ottawa quality assessment scale appraised the quality of the eligible studies.Effect estimates,expressed as proportions or standardized mean differences,were combined using the randomeffects,generic inverse variance method of DerSimonian and Laird.Subgroup,sensitivity analysis,and meta-regressions were applied to assess heterogeneity.RESULTS QTc combined mean in patients with cirrhosis was 444.8 ms[95%confidence interval(CI):440.4-449.2;P<0.001 when compared with the upper normal limit of 440 ms],presenting high heterogeneity(I2=97.5%;95%CI:97.2%-97.8%);both Egger’s and Begg’s tests showed non-significance.QTc was elongated in patients with cirrhosis compared with controls(P<0.001).QTc was longer in patients with Child-Pugh C cirrhosis when compared with Child-Pugh B and A(P<0.001);Child-Pugh B patients presented longer QTc when compared with Child-Pugh A patients(P=0.003).The MELD score was higher in patients with cirrhosis with QTc>440 ms when compared with QTc≤440 ms(P<0.001).No correlation of QTc with age(P=0.693),sex(P=0.753),or etiology(P=0.418)was detected.β-blockers shortened QTc(P<0.001).QTc was prolonged during acute gastrointestinal bleeding(P=0.020).Tx tended to improve QTc(P<0.001).No other sources of QTc heterogeneity were revealed.CONCLUSION QTc is prolonged in cirrhosis independently of sex,age,and etiology but is correlated with severity and affected byβ-blockers and acute gastrointestinal bleeding.QTc is improved after liver Tx. 展开更多
关键词 Liver cirrhosis corrected QT interval Child-Pugh stage Model for end-stage liver disease score Liver transplantation META-ANALYSIS
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Correction:Nanomaterial-Based Repurposing of Macrophage Metabolism and Its Applications
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作者 Tingting Meng Danfeng He +7 位作者 Zhuolei Han Rong Shi Yuhan Wang Bibo Ren Cheng Zhang Zhengwei Mao Gaoxing Luo Jun Deng 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第12期357-357,共1页
Following publication of the original article[1],the authors reported an error in the last author’s name,it was mistakenly written as“Jun Den”.The correct author’s name“Jun Deng”has been updated in this Correction.
关键词 MISTAKE correct correctION
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Toward Constructing a Continuous Logical Operator for Error-Corrected Quantum Sensing
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作者 Cameron Cianci 《Journal of Quantum Information Science》 2023年第2期45-55,共11页
Error correction has long been suggested to extend the sensitivity of quantum sensors into the Heisenberg Limit. However, operations on logical qubits are only performed through universal gate sets consisting of finit... Error correction has long been suggested to extend the sensitivity of quantum sensors into the Heisenberg Limit. However, operations on logical qubits are only performed through universal gate sets consisting of finite-sized gates such as Clifford + T. Although these logical gate sets allow for universal quantum computation, the finite gate sizes present a problem for quantum sensing, since in sensing protocols, such as the Ramsey measurement protocol, the signal must act continuously. The difficulty in constructing a continuous logical op-erator comes from the Eastin-Knill theorem, which prevents a continuous sig-nal from being both fault-tolerant to local errors and transverse. Since error correction is needed to approach the Heisenberg Limit in a noisy environment, it is important to explore how to construct fault-tolerant continuous operators. In this paper, a protocol to design continuous logical z-rotations is proposed and applied to the Steane Code. The fault tolerance of the designed operator is investigated using the Knill-Laflamme conditions. The Knill-Laflamme condi-tions indicate that the diagonal unitary operator constructed cannot be fault tolerant solely due to the possibilities of X errors on the middle qubit. The ap-proach demonstrated throughout this paper may, however, find success in codes with more qubits such as the Shor code, distance 3 surface code, [15, 1, 3] code, or codes with a larger distance such as the [11, 1, 5] code. 展开更多
关键词 Quantum Sensing Quantum Error correction Steane Code Heisenberg Limit
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Adaptation analysis and fusion correction method of CMIP6 precipitation simulation data on the Qinghai-Tibetan Plateau
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作者 PENG Hao QIN Dahui +3 位作者 WANG Zegen ZHANG Menghan YANG Yanmei YONG Zhiwei 《Journal of Mountain Science》 SCIE CSCD 2024年第2期555-573,共19页
In order to obtain more accurate precipitation data and better simulate the precipitation on the Tibetan Plateau,the simulation capability of 14 Coupled Model Intercomparison Project Phase 6(CMIP6)models of historical... In order to obtain more accurate precipitation data and better simulate the precipitation on the Tibetan Plateau,the simulation capability of 14 Coupled Model Intercomparison Project Phase 6(CMIP6)models of historical precipitation(1982-2014)on the Qinghai-Tibetan Plateau was evaluated in this study.Results indicate that all models exhibit an overestimation of precipitation through the analysis of the Taylor index,temporal and spatial statistical parameters.To correct the overestimation,a fusion correction method combining the Backpropagation Neural Network Correction(BP)and Quantum Mapping(QM)correction,named BQ method,was proposed.With this method,the historical precipitation of each model was corrected in space and time,respectively.The correction results were then analyzed in time,space,and analysis of variance(ANOVA)with those corrected by the BP and QM methods,respectively.Finally,the fusion correction method results for each model were compared with the Climatic Research Unit(CRU)data for significance analysis to obtain the trends of precipitation increase and decrease for each model.The results show that the IPSL-CM6A-LR model is relatively good in simulating historical precipitation on the Qinghai-Tibetan Plateau(R=0.7,RSME=0.15)among the uncorrected data.In terms of time,the total precipitation corrected by the fusion method has the same interannual trend and the closest precipitation values to the CRU data;In terms of space,the annual average precipitation corrected by the fusion method has the smallest difference with the CRU data,and the total historical annual average precipitation is not significantly different from the CRU data,which is better than BP and QM.Therefore,the correction effect of the fusion method on the historical precipitation of each model is better than that of the QM and BP methods.The precipitation in the central and northeastern parts of the plateau shows a significant increasing trend.The correlation coefficients between monthly precipitation and site-detected precipitation for all models after BQ correction exceed 0.8. 展开更多
关键词 GCM CMIP6 Precipitation correction BP-QM fusion correction Spatio-temporal characteristics
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Correction: Surface Patterning of Metal ZincElectrode with an In-Region Zincophilic Interfacefor High-Rate and Long-Cycle-Life Zinc MetalAnode
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作者 Tian Wang Qiao Xi +8 位作者 Kai Yao Yuhang Liu Hao Fu Venkata Siva Kavarthapu Jun Kyu Lee Shaocong Tang Dina Fattakhova-Rohlfing Wei Ai Jae Su Yu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第7期456-457,共2页
Correction to:Nano-Micro Letters(2024)16:112 https://doi.org/10.1007/s40820-024-01327-2 In the supplementary information the following corrections have been carried out:1.Institute of Energy and Climate Research,Mater... Correction to:Nano-Micro Letters(2024)16:112 https://doi.org/10.1007/s40820-024-01327-2 In the supplementary information the following corrections have been carried out:1.Institute of Energy and Climate Research,Materials Synthesis and Processing,Forschungszentrum Jülich GmbH,52425 Jülich,Germany.Corrected:Institute of Energy and Climate Research:Materials Synthesis and Processing(IEK-1),Forschungszentrum Jülich GmbH,52425 Jülich,Germany. 展开更多
关键词 correctION ZINC ELECTRODE
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Author Correction:Recent Progress in Interfacial Dipole Engineering for Perovskite Solar Cells
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作者 Yinyi Ma Jue Gong +1 位作者 Peng Zeng Mingzhen Liu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期500-500,共1页
In the version of this Article originally published online,there was an error in the schematics of Figures 2b and 2c.These errors have now been corrected in the original article.
关键词 corrected ERROR Solar
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Correction to:Error Calculation of Large-Amplitude Internal Solitary Waves Within the Pycnocline Introduced by the Strong Stratification Approximation
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作者 Cunguo Xu Zhan Wang Masoud Hayatdavoodi 《哈尔滨工程大学学报(英文版)》 CSCD 2024年第1期247-247,共1页
In the original publication the third author name is published incorrectly as“Hayatdavoodi Masoud”.The correct author name should be read as“Masoud Hayatdavoodi”.The correct author name is available in this correc... In the original publication the third author name is published incorrectly as“Hayatdavoodi Masoud”.The correct author name should be read as“Masoud Hayatdavoodi”.The correct author name is available in this correction. 展开更多
关键词 STRONG Internal correctION
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Corrective-Net:面向多标签文本分类的标签关联学习模块
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作者 肖新正 黄瑞章 +3 位作者 陈艳平 秦永彬 宋玉梅 周裕林 《计算机工程与科学》 CSCD 北大核心 2024年第6期1092-1100,共9页
在目前的多标签文本分类任务中,主要面临以下2个问题:(1)侧重文本表示学习,对标签之间的关联信息建模不充分;(2)尽管使用了标签关联信息来改善多标签分类任务,但对标签关联的建模过于依赖人工预定义的外部知识,而外部知识的获取成本高昂... 在目前的多标签文本分类任务中,主要面临以下2个问题:(1)侧重文本表示学习,对标签之间的关联信息建模不充分;(2)尽管使用了标签关联信息来改善多标签分类任务,但对标签关联的建模过于依赖人工预定义的外部知识,而外部知识的获取成本高昂,限制了其实际应用。针对以上问题,提出了一种面向多标签文本分类的标签关联学习模块Corrective-Net。该模块可以在不依赖外部知识的前提下,自动学习数据中的标签关联信息;同时,它还可以利用标签关联信息,对基础分类模块的初始预测结果进行修正,使得最终预测兼顾语义信息和标签关联信息,以获得更精准的多标签预测结果。在AAPD和SO数据集上的大量实验表明,Corrective-Net具有通用性和有效性,通过分析标签修正对各个标签性能的影响,得到了显式的标签关联信息,并进行了可视化。 展开更多
关键词 标签关联 标签修正 多标签 文本分类 可视化
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Correction: MicroRNA-329-3p inhibits the Wnt/β-catenin pathway and proliferation of osteosarcoma cells by targeting transcription factor 7-like 1
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作者 HUI SUN MASANORI KAWANO +4 位作者 TATSUYA IWASAKI ICHIRO ITONAGA YUTA KUBOTA HIROSHI TSUMURA KAZUHIRO TANAKA 《Oncology Research》 SCIE 2024年第8期1369-1370,共2页
In the article‘MicroRNA-329-3p inhibits the Wnt/β-catenin pathway and proliferation of osteosarcoma cells by targeting transcription factor 7-like 1’(Oncology Research,2024,Vol.32,No.3,pp.463−476.doi:10.32604/or.20... In the article‘MicroRNA-329-3p inhibits the Wnt/β-catenin pathway and proliferation of osteosarcoma cells by targeting transcription factor 7-like 1’(Oncology Research,2024,Vol.32,No.3,pp.463−476.doi:10.32604/or.2023.044085),there was an error in the compilation of Fig.8D.We have revised Fig.8D to correct this error.A corrected version of Fig.8 is provided.This correction does not change any results or conclusions of the article.We apologize for any inconvenience caused. 展开更多
关键词 OSTEOSARCOMA correctION revised
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Real-time model correction using Kalman filter for Raman-controlled cell culture processes
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作者 Xiaoxiao Dong Zhuohong He +5 位作者 Xu Yan Dong Gao Jingyu Jiao Yan Sun Haibin Wang Haibin Qu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第6期251-260,共10页
Raman spectroscopy has found extensive use in monitoring and controlling cell culture processes.In this context,the prediction accuracy of Raman-based models is of paramount importance.However,models established with ... Raman spectroscopy has found extensive use in monitoring and controlling cell culture processes.In this context,the prediction accuracy of Raman-based models is of paramount importance.However,models established with data from manually fed-batch cultures often exhibit poor performance in Raman-controlled cultures.Thus,there is a need for effective methods to rectify these models.The objective of this paper is to investigate the efficacy of Kalman filter(KF)algorithm in correcting Raman-based models during cell culture.Initially,partial least squares(PLS)models for different components were constructed using data from manually fed-batch cultures,and the predictive performance of these models was compared.Subsequently,various correction methods including the PLS-KF-KF method proposed in this study were employed to refine the PLS models.Finally,a case study involving the auto-control of glucose concentration demonstrated the application of optimal model correction method.The results indicated that the original PLS models exhibited differential performance between manually fed-batch cultures and Raman-controlled cultures.For glucose,the root mean square error of prediction(RMSEP)of manually fed-batch culture and Raman-controlled culture was 0.23 and 0.40 g·L^(-1).With the implementation of model correction methods,there was a significant improvement in model performance within Raman-controlled cultures.The RMSEP for glucose from updating-PLS,KF-PLS,and PLS-KF-KF was 0.38,0.36 and 0.17 g·L^(-1),respectively.Notably,the proposed PLS-KF-KF model correction method was found to be more effective and stable,playing a vital role in the automated nutrient feeding of cell cultures. 展开更多
关键词 Raman spectroscopy Model correction Algorithm Model-predictive control BIOPROCESS
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The application of the strip-shaped cymba conchae orthosis in the nonsurgical correction of complex auricular deformity
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作者 Huijuan Xu Shaoguang Ding +6 位作者 Fei Zhang Zhifeng Zhang Xiangyu Chen Mingyang Li Haitao Yang Fugen Han Hongjian Liu 《Journal of Otology》 CAS CSCD 2024年第1期24-29,共6页
Objective: This study aims to evaluate the efficacy and safety of using a strip-shaped cymba conchae orthosis for the nonsurgical correction of complex auricular deformities. Methods: Clinical data were collected from... Objective: This study aims to evaluate the efficacy and safety of using a strip-shaped cymba conchae orthosis for the nonsurgical correction of complex auricular deformities. Methods: Clinical data were collected from 2020 to 2021 for 6 patients who underwent correction using a stripshaped cymba conchae orthosis. The indications, corrective effects, and complications associated with use of the orthosis were analyzed. Results: There were four indications for treatment: cryptotia with helix adhesion;cryptotia with grade I microtia;cryptotia with excessive helix thickness;and auricular deformity beyond the treatment time window(≥6 months). Excellent corrective effects were observed in all 6 patients. Complications occurred in one patient, who recovered after symptomatic treatment. Conclusion: The use of a strip-shaped cymba conchae orthosis alone or combined with a U-shaped helix orthosis presents a feasible approach for correcting complex auricular deformities or deformities beyond the treatment time window in pediatric patients. 展开更多
关键词 Cymba conchae Auricular deformity Cryptotia Nonsurgical correction ORTHOSIS
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Iterative Subregion Correction Preconditioners with Adaptive Tolerance for Problems with Geometrically Localized Stiffness
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作者 Michael Franco Per-Olof Persson Will Pazner 《Communications on Applied Mathematics and Computation》 EI 2024年第2期811-836,共26页
We present a class of preconditioners for the linear systems resulting from a finite element or discontinuous Galerkin discretizations of advection-dominated problems.These preconditioners are designed to treat the ca... We present a class of preconditioners for the linear systems resulting from a finite element or discontinuous Galerkin discretizations of advection-dominated problems.These preconditioners are designed to treat the case of geometrically localized stiffness,where the convergence rates of iterative methods are degraded in a localized subregion of the mesh.Slower convergence may be caused by a number of factors,including the mesh size,anisotropy,highly variable coefficients,and more challenging physics.The approach taken in this work is to correct well-known preconditioners such as the block Jacobi and the block incomplete LU(ILU)with an adaptive inner subregion iteration.The goal of these preconditioners is to reduce the number of costly global iterations by accelerating the convergence in the stiff region by iterating on the less expensive reduced problem.The tolerance for the inner iteration is adaptively chosen to minimize subregion-local work while guaranteeing global convergence rates.We present analysis showing that the convergence of these preconditioners,even when combined with an adaptively selected tolerance,is independent of discretization parameters(e.g.,the mesh size and diffusion coefficient)in the subregion.We demonstrate significant performance improvements over black-box preconditioners when applied to several model convection-diffusion problems.Finally,we present performance results of several variations of iterative subregion correction preconditioners applied to the Reynolds number 2.25×10^(6)fluid flow over the NACA 0012 airfoil,as well as massively separated flow at 30°angle of attack. 展开更多
关键词 Subregion correction Nested Krylov Geometrically localized stiffness
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Methodology for local correction of the heights of global geoid models to improve the accuracy of GNSS leveling
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作者 Stepan Savchuk Alina Fedorchuk 《Geodesy and Geodynamics》 EI CSCD 2024年第1期42-49,共8页
At present,one of the methods used to determine the height of points on the Earth’s surface is Global Navigation Satellite System(GNSS)leveling.It is possible to determine the orthometric or normal height by this met... At present,one of the methods used to determine the height of points on the Earth’s surface is Global Navigation Satellite System(GNSS)leveling.It is possible to determine the orthometric or normal height by this method only if there is a geoid or quasi-geoid height model available.This paper proposes the methodology for local correction of the heights of high-order global geoid models such as EGM08,EIGEN-6C4,GECO,and XGM2019e_2159.This methodology was tested in different areas of the research field,covering various relief forms.The dependence of the change in corrected height accuracy on the input data was analyzed,and the correction was also conducted for model heights in three tidal systems:"tide free","mean tide",and"zero tide".The results show that the heights of EIGEN-6C4 model can be corrected with an accuracy of up to 1 cm for flat and foothill terrains with the dimensionality of 1°×1°,2°×2°,and 3°×3°.The EGM08 model presents an almost identical result.The EIGEN-6C4 model is best suited for mountainous relief and provides an accuracy of 1.5 cm on the 1°×1°area.The height correction accuracy of GECO and XGM2019e_2159 models is slightly poor,which has fuzziness in terms of numerical fluctuation. 展开更多
关键词 GNSS leveling Global geoid model Gravity anomaly Weight data correcting data
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Automatic Miscalibration Detection and Correction of LiDAR and Camera Using Motion Cues
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作者 Pai Peng Dawei Pi +3 位作者 Guodong Yin Yan Wang Liwei Xu Jiwei Feng 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期318-329,共12页
This paper aims to develop an automatic miscalibration detection and correction framework to maintain accurate calibration of LiDAR and camera for autonomous vehicle after the sensor drift.First,a monitoring algorithm... This paper aims to develop an automatic miscalibration detection and correction framework to maintain accurate calibration of LiDAR and camera for autonomous vehicle after the sensor drift.First,a monitoring algorithm that can continuously detect the miscalibration in each frame is designed,leveraging the rotational motion each individual sensor observes.Then,as sensor drift occurs,the projection constraints between visual feature points and LiDAR 3-D points are used to compute the scaled camera motion,which is further utilized to align the drifted LiDAR scan with the camera image.Finally,the proposed method is sufficiently compared with two representative approaches in the online experiments with varying levels of random drift,then the method is further extended to the offline calibration experiment and is demonstrated by a comparison with two existing benchmark methods. 展开更多
关键词 Autonomous vehicle LiDAR and camera Miscalibration detection and correction Sensor drift
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Balancing act:The dilemma of rapid hyperglycemia correction in diabetes management
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作者 Ke-Xin Zhang Cheng-Xia Kan Xiao-Dong Sun 《World Journal of Diabetes》 SCIE 2024年第2期129-132,共4页
The global diabetes surge poses a critical public health challenge,emphasizing the need for effective glycemic control.However,rapid correction of chronic hyperglycemia can unexpectedly trigger microvascular complicat... The global diabetes surge poses a critical public health challenge,emphasizing the need for effective glycemic control.However,rapid correction of chronic hyperglycemia can unexpectedly trigger microvascular complications,necessitating a reevaluation of the speed and intensity of glycemic correction.Theories suggest swift blood sugar reductions may cause inflammation,oxidative stress,and neurovascular changes,resulting in complications.Healthcare providers should cautiously approach aggressive glycemic control,especially in long-standing,poorly controlled diabetes.Preventing and managing these complications requires a personalized,comprehensive approach with education,monitoring,and interdisciplinary care.Diabetes management must balance short and longterm goals,prioritizing overall well-being.This editorial underscores the need for a personalized,nuanced approach,focusing on equilibrium between glycemic control and avoiding overcorrection. 展开更多
关键词 DIABETES Hyperglycemia correction Management Microvascular complications Glucose control
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Chord length sampling correction analysis for dispersion fuel in Monte Carlo simulation
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作者 Zhao-Yu Liang Ding She +1 位作者 Yu-Tong Wen Lei Shi 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第4期57-64,共8页
Dispersion fuels,knowned for their excellent safety performance,are widely used in advanced reactors,such as hightemperature gas-cooled reactors.Compared with deterministic methods,the Monte Carlo method has more adva... Dispersion fuels,knowned for their excellent safety performance,are widely used in advanced reactors,such as hightemperature gas-cooled reactors.Compared with deterministic methods,the Monte Carlo method has more advantages in the geometric modeling of stochastic media.The explicit modeling method has high computational accuracy and high computational cost.The chord length sampling(CLS)method can improve computational efficiency by sampling the chord length during neutron transport using the matrix chord length?s probability density function.This study shows that the excluded-volume effect in realistic stochastic media can introduce certain deviations into the CLS.A chord length correction approach is proposed to obtain the chord length correction factor by developing the Particle code based on equivalent transmission probability.Through numerical analysis against reference solutions from explicit modeling in the RMC code,it was demonstrated that CLS with the proposed correction method provides good accuracy for addressing the excludedvolume effect in realistic infinite stochastic media. 展开更多
关键词 Stochastic media Monte Carlo Chord length sampling Excluded-volume effect Chord length correction
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