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Galerkin-based quasi-smooth manifold element(QSME)method for anisotropic heat conduction problems in composites with complex geometry

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 137-154页

作者： Pan WANG Xiangcheng HAN Weibin wen Baolin WANG jun LIANG School of Civil Engineering Central South UniversityChangsha 410083China Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China School of Science Harbin Institute of TechnologyShenzhen 518055Guangdong ProvinceChina

The accurate and efficient analysis of anisotropic heat conduction problems in complex composites is crucial for structural design and performance evaluation. Traditional numerical methods, such as the finite element method(FEM), often face a trade-off between calculation accuracy and efficiency. In this paper, we propose a quasi-smooth manifold element(QSME) method to address this challenge, and provide the accurate and efficient analysis of two-dimensional(2D) anisotropic heat conduction problems in composites with complex geometry. The QSME approach achieves high calculation precision by a high-order local approximation that ensures the first-order derivative *** results demonstrate that the QSME method is robust and stable, offering both high accuracy and efficiency in the heat conduction analysis. With the same degrees of freedom(DOFs), the QSME method can achieve at least an order of magnitude higher calculation accuracy than the traditional FEM. Additionally, under the same level of calculation error, the QSME method requires 10 times fewer DOFs than the traditional FEM. The versatility of the proposed QSME method extends beyond anisotropic heat conduction problems in complex composites. The proposed QSME method can also be applied to other problems, including fluid flows, mechanical analyses, and other multi-field coupled problems, providing accurate and efficient numerical simulations.

关键词： anisotropic heat conduction quasi-smooth manifold element(QSME) composite with complex geometry numerical simulation finite element method(FEM)

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Suppression of low-frequency ultrasound broadband vibration using star-shaped single-phase metamaterials

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Defence Technology（防务技术） 2024年第4期34卷 217-224页

作者： Rui Zhao Jian Zheng Jin guo Yunbo Shi Hengzhen Feng jun Tang jun Liu Science and Technology on Electronic Test&Measurement Laboratory North University of ChinaTaiyuan 030051ShanxiChina School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

In order to suppress the low-frequency ultrasound vibration in the broadband range of 20 k Hz—100 k Hz,this paper proposes and discusses an acoustic metamaterial with low-frequency ultrasound vibration attenuation properties,which is configured by hybrid arc and sharp-angle convergent star-shaped *** effect of the dispersion relation and the bandgap characteristic for the scatterers in star-shaped are simulated and *** target bandgap width is extended by optimizing the geometry parameters of arc and sharp-angle convergent *** proposed metamaterial configured by optimized hybrid lattices exhibits remarkable broad bandgap characteristics by bandgap complementarity,and the simulation results verify a 99%vibration attenuation amplitude can be obtained in the frequency of20 k Hz—100 k *** the fabrication of the proposed hybrid configurational star-shaped metamaterial by 3D printing technique,the transmission loss experiments are performed,and the experimental results indicate that the fabricated metamaterial has the characteristics of broadband vibration attenuation and an amplitude greater than 85%attenuation for the target *** results demonstrate that the hybrid configurational star-shaped metamaterials can effectively widen the bandgap and realize high efficiency attenuation,which has capability for the vibration attenuation in the application of highprecise equipment.

关键词： Star-shaped metamaterials Broadband Vibration attenuation Low-frequency ultrasound vibration Transmission loss

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贝叶斯深度神经网络对于核质量预测的研究

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物理学报 2022年第10期71卷 32-41页

作者：娄月申郭文军上海理工大学物理系上海200093

采用贝叶斯深度神经网络对液滴模型进行优化改进,并运用KL(Kullback-Leibler)散度与变分推断的方法使得模型便于实现.以最新的原子核数据(AME2020)中2457个有精确值的原子核(Z≥8和N≥8)作为总数据集,随机选取其中80%的数据为训练集用... 详细信息

采用贝叶斯深度神经网络对液滴模型进行优化改进,并运用KL(Kullback-Leibler)散度与变分推断的方法使得模型便于实现.以最新的原子核数据(AME2020)中2457个有精确值的原子核(Z≥8和N≥8)作为总数据集,随机选取其中80%的数据为训练集用于模型训练,通过预测余下的20%进行模型验证.最终两个数据集的误差均方根(RMS)基本相等,而且全部数据的RMS从2.9894 Me V降到0.5695 Me V,下降了80%,呈现出较好的结果.此模型进行了输入参数上的改进(区域限定策略),使得未知核(Z=118—126)可以被限定在一个固定的区域内,从而提高了预测的准确性.为了验证这一性质,对实验数据(Z=100—117)进行了预测计算,结果也与实验值符合得很好.最后使用该方案对未知元素Z=118—126进行了预测,为以后寻找新元素提供了新思路.

关键词：结合能贝叶斯深度神经网络液滴模型区域限定策略

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Transferable adversarial slow feature extraction network for few-shot quality prediction in coal-to-ethylene glycol process

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Chinese Journal of Chemical Engineering 2024年第7期71卷 258-271页

作者： Cheng Yang Chao Jiang guo Yu jun Li Cuimei Bo School of Electrical Engineering and Control Science Nanjing Tech UniversityNanjing 211816China Department of Intelligent Manufacturing Nanjing Tech UniversityNanjing 210009China

In the coal-to-ethylene glycol(CTEG)process,precisely estimating quality variables is crucial for process monitoring,optimization,and control.A significant challenge in this regard is relying on offline laboratory analysis to obtain these variables,which often incurs substantial monetary costs and significant time *** resulting few-shot learning scenarios present a hurdle to the efficient development of predictive *** address this issue,our study introduces the transferable adversarial slow feature extraction network(TASF-Net),an innovative approach designed specifically for few-shot quality prediction in the CTEG ***-Net uniquely integrates the slowness principle with a deep Bayesian framework,effectively capturing the nonlinear and inertial characteristics of the CTEG ***,the model employs a variable attention mechanism to identify quality-related input variables adaptively at each time step.A key strength of TASF-Net lies in its ability to navigate the complex measurement noise,outliers,and system interference typical in CTEG *** learning strategy using a min-max game is adopted to improve its robustness and ability to model irregular industrial data accurately and ***,an incremental refining transfer learning framework is designed to further improve few-shot prediction performance achieved by transferring knowledge from the pretrained model on the source domain to the target *** effectiveness and superiority of TASF-Net have been empirically validated using a real-world CTEG *** with some state-of-the-art methods,TASF-Net demonstrates exceptional capability in addressing the intricate challenges for few-shot quality prediction in the CTEG process.

关键词： Chemical process Neural networks Slowness principle Transfer learning Prediction

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China stroke surveillance report 2021

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Military Medical Research 2024年第3期11卷 374-399页

作者： wen-jun Tu Long-De Wang 无 Department of Neurosurgery Beijing Tiantan HospitalCapital Medical UniversityBeijing 100070China School of Public Health Peking UniversityBeijing 100191China Special Writing Group of China Stroke Surveillance Report

Since 2015,stroke has become the leading cause of death and disability in China,posing a significant threat to the health of its citizens as a major chronic non-communicable *** to the China Stroke High-risk Population Screening and Intervention Program,an estimated 17.8 million[95%confidence interval(CI)17.6–18.0million]adults in China had experienced a stroke in 2020,with 3.4 million(95%CI 3.3–3.5 million)experiencing their first-ever stroke and another 2.3 million(95%CI 2.2–2.4 million)dying as a ***,approximately 12.5%(95%CI 12.4%–12.5%)of stroke survivors were left disabled,as defined by a modified Rankin Scale score greater than 1,equating to 2.2 million(95%CI 2.1–2.2 million)stroke-related disabilities in *** the population ages and the prevalence of risk factors like diabetes,hypertension,and hyperlipidemia continues to rise and remains poorly controlled,the burden of stroke in China is also increasing.A large national epidemiological survey initiated by the China Hypertension League in 2017 showed that the prevalence of hypertension was 24.7%;the awareness,treatment,and control rates in hypertensive patients were:60.1%,42.5%,and 25.4%,respectively.A nationally representative sample of the Chinese mainland population showed that the weighted prevalence of total diabetes diagnosed by the American Diabetes Association criteria was 12.8%,suggesting there are 120 million adults with diabetes in China,and the awareness,treatment,and control rates in diabetic patients were:43.3%,49.0%,and 49.4%,***“Sixth National Health Service Statistical Survey Report in 2018”showed that the proportion of the obese population in China was 37.4%,an increase of 7.2 points from *** from 1599 hospitals in the Hospital Quality Monitoring System and Bigdata Observatory Platform for Stroke of China(BOSC)showed that a total of 3,418,432 stroke cases[mean age±standard error(SE)was(65.700±0.006)years,and 59.1%were male]were admitted dur

关键词： Stroke Epidemiological characteristics Treatment Prognosis China

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Establishment and validation of a predictive model for peripherally inserted central catheter-related thrombosis in patients with liver cancer

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 2221-2231页

作者： Xiao-Fei Chen Hao-jun Wu Tang Li Jia-Bin Liu wen-Jie Zhou Qiang guo Department of Thyroid Surgery West China Hospital of Sichuan UniversityChengdu 610041Sichuan ProvinceChina The Second Department of General Surgery Chengdu Shangjinnanfu HospitalWest China Hospital of Sichuan UniversityChengdu 611730Sichuan ProvinceChina Department of Biliary Surgery West China Hospital of Sichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Hepatobiliary and Pancreatic Surgery Chengdu Shangjinnanfu HospitalWest China Hospital of Sichuan UniversityChengdu 611730Sichuan ProvinceChina Department of Vascular Surgery West China Hospital of Sichuan UniversityChengdu 610041Sichuan ProvinceChina

BACKGROUND Peripherally inserted central catheters(PICCs)are commonly used in hospitalized patients with liver cancer for the administration of chemotherapy,nutrition,and other ***,PICC-related thrombosis is a serious complication that can lead to morbidity and mortality in this patient *** risk factors have been identified for the development of PICC-related thrombosis,including cancer type,stage,comorbidities,and catheter *** these risk factors and developing a predictive model can help healthcare providers identify high-risk patients and implement preventive measures to reduce the incidence of *** To analyze the influencing factors of PICC-related thrombosis in hospitalized patients with liver cancer,construct a predictive model,and validate *** Clinical data of hospitalized patients with liver cancer admitted from January 2020 to December 2023 were ***-five cases of PICC-related thrombosis in hospitalized patients with liver cancer were collected,and 220 patients who underwent PICC placement during the same period but did not develop PICC-related thrombosis were randomly selected as controls.A total of 255 samples were collected and used as the training set,and 77 cases were collected as the validation set in a 7:3 *** patient information,case data,catheterization data,coagulation indicators,and Autar Thrombosis Risk Assessment Scale scores were *** and multivariate unconditional logistic regression analyses were performed on relevant factors,and the value of combined indicators in predicting PICC-related thrombosis in hospitalized patients with liver cancer was evaluated using receiver operating characteristic(ROC)curve *** Univariate analysis showed statistically significant differences(P<0.05)in age,sex,Karnofsky performance status score(KPS),bedridden time,activities of daily living impairment,parenteral nutrition,catheter duration,d

关键词： Liver cancer Peripherally inserted central catheters Thrombosis Model Verify

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Correlation between longitudinal crack occurrence and mold heat transfer in continuous casting based on process data mining

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Journal of Iron and Steel Research International 2024年第5期31卷 1139-1152页

作者： Zhi-qiang Peng Zi-bing Hou Kai Yi Kun-hui guo Dong-wei guo Guang-hua wen College of Materials Science and Engineering Chongqing UniversityChongqing400044China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing400044China

The correlation between the longitudinal crack occurrence and integrated heat transfer of the mold with data mining methods was ***,three kinds of support vector machine models based on principal component analysis with different input features were established to explore the effect of integrated heat transfer on the accuracy of the prediction model for the longitudinal *** results show that the accuracy was improved while features including mean and standard deviation of integrated heat transfer were ***,the difference in integrated heat transfer between defect and normal samples under the same process parameters was quantitatively *** with normal samples,the temperature difference of cooling water for defect samples decreased by 0.65%,and the temperature difference fluctuation increased by 31.1%.Finally,the literature data were used to provide support for the quantitative correlation according to defect formation mechanism.A new criterion for the prediction of longitudinal crack and a discovering method for correlation between product quality and process parameters in the manufacturing industry have been provided.

关键词： Continuous casting slab Longitudinal surface crack Heat transfer Data mining Quantitative correlation

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Pan-immune-inflammation value as a prognostic biomarker for colon cancer and its variation by primary tumor location

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World Journal of Gastroenterology 2024年第33期30卷 3823-3836页

作者： Qian-Yu Wang wen-Tao Zhong Yi Xiao guo-Le Lin jun-Yang Lu Lai Xu Guan-Nan Zhang jun-Feng Du Bin Wu Department of General Surgery Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China Medical Department of General Surgery The First Medical CenterChinese PLA General HospitalBeijing 100853China

BACKGROUND A growing body of research indicates significant differences between left-sided colon cancers(LCC)and right-sided colon cancers(RCC).Pan-immune-inflammation value(PIV)is a systemic immune response marker that can predict the prognosis of patients with colon ***,the specific distinction between PIV of LCC and RCC remains *** To investigate the prognostic and clinical significance of PIV in LCC and RCC *** This multicenter retrospective cohort study included 1510 patients with colon cancer,comprising 801 with LCC and 709 with *** used generalized lifting regression analysis to evaluate the relative impact of PIV on disease-free survival(DFS)in these ***-Meier analysis,as well as univariate and multivariate analyses,were used to examine the risk factors for *** correlation between PIV and the clinical characteristics was statistically analyzed in these *** A total of 1510 patients{872 female patients(58%);median age 63 years[interquartile ranges(IQR):54-71];patients with LCC 801(53%);median follow-up 44.17 months(IQR 29.67-62.32)}were *** was significantly higher in patients with RCC[median(IQR):214.34(121.78-386.72)vs 175.87(111.92-286.84),P227.84)was associated with worse DFS in LCC[PIV-high:Adjusted hazard ratio(aHR)=2.39;95%confidence interval:1.70-3.38;P<0.001]but not in RCC(PIV-high:aHR=0.72;95%confidence interval:0.48-1.08;P=0.114).CONCLUSION These findings suggest that PIV may predict recurrence in patients with LCC but not RCC,underscoring the importance of tumor location when using PIV as a colon cancer biomarker.

关键词： Colon cancer Left-sided colon cancer Right-sided colon cancer Pan-immune-inflammation value Systemic inflammatory biomarkers Prognosis

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Oilfield analogy and productivity prediction based on machine learning: Field cases in PL oilfield, China

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Petroleum Science 2024年第4期21卷 2554-2570页

作者： wen-Peng Bai Shi-Qing Cheng Xin-Yang guo Yang Wang Qiao guo Chao-Dong Tan State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum (Beijing)

In the early time of oilfield development, insufficient production data and unclear understanding of oil production presented a challenge to reservoir engineers in devising effective development plans. To address this challenge, this study proposes a method using data mining technology to search for similar oil fields and predict well productivity. A query system of 135 analogy parameters is established based on geological and reservoir engineering research, and the weight values of these parameters are calculated using a data algorithm to establish an analogy system. The fuzzy matter-element algorithm is then used to calculate the similarity between oil fields, with fields having similarity greater than 70% identified as similar oil fields. Using similar oil fields as sample data, 8 important factors affecting well productivity are identified using the Pearson coefficient and mean decrease impurity（MDI） method. To establish productivity prediction models, linear regression（LR）, random forest regression（RF）, support vector regression（SVR）, backpropagation（BP）, extreme gradient boosting（XGBoost）, and light gradient boosting machine（Light GBM） algorithms are used. Their performance is evaluated using the coefficient of determination（R2）, explained variance score（EV）, mean squared error（MSE）, and mean absolute error（MAE） metrics. The Light GBM model is selected to predict the productivity of 30 wells in the PL field with an average error of only 6.31%, which significantly improves the accuracy of the productivity prediction and meets the application requirements in the field. Finally, a software platform integrating data query,oil field analogy, productivity prediction, and knowledge base is established to identify patterns in massive reservoir development data and provide valuable technical references for new reservoir development.

关键词： Data mining technique Analogy parameters Oilfield analogy Productivity prediction Software platform

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“Co-coordination force”assisted rigid-flexible coupling crystalline polymer for high-performance aqueous zinc-organic batteries

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Chinese Chemical Letters 2024年第9期35卷 501-506页

作者： jun guo Zhenbang Zhuang Wanqiang Liu Gang Huang School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun 130022China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Key Laboratory of Automobile Materials Ministry of EducationDepartment of Materials Science and EngineeringJilin UniversityChangchun 130022China

Organic electrode materials(OEMs)have attracted substantial attention for aqueous zinc-ion batteries(AZIBs)due to their advantages in relieving resource and environmental ***,the potential of OEMs is plagued by their low achievable capacity and high ***,we have proposed a new concept of“co-coordination force”and designed a rigid-flexible coupling crystalline polymer that can overcome the abovementioned *** obtained crystalline polymer(BQSPNs)with multiredox centres makes the BQSPNs exist intermolecular hydrogen bonds(HB)among-C=O,-C=N,and-NH and consequently exhibits transverse two-dimensional arrays and longitudinalπ-πstacking ***,in-situ FTIR,Raman,variable temperature FTIR spectra,and 2D nuclear overhauser effect spectroscopy(NOESY)well capture the existence and evolution process of HB during the electrochemistry reaction process of BQSPNs,uncovering the effect of HB in stabilizing the structure and promoting the reaction *** a result,the BQSPNs with rationally designed“co-coordination force”deliver a high capacity of 459.6 m Ah/g and a stable cycling lifetime for more than 100,000 cycles at 10 A/g in *** results disclose the HB effect and provide a brand-new strategy for high-performance OEMs design.

关键词： Co-coordination force Crystalline polymer Hydrogen bonds Organic electrode materials Aqueous zinc-ion batteries

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