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Using deep neural networks coupled with principal component analysis for ore production forecasting at open-pit mines

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 727-740页

作者： Chengkai Fan na Zhang Bei Jiang Wei Victor Liu Department of Civil and Environmental Engineering University of AlbertaEdmontonAlbertaT6G 2E3Canada Department of Mathematical and Statistical Sciences University of AlbertaEdmontonAlbertaT6G 2G1Canada

Ore production is usually affected by multiple influencing inputs at open-pit ***,the complex nonlinear relationships between these inputs and ore production remain *** becomes even more challenging when training data(*** haulage information and weather conditions)are *** machine learning(ML)algorithms,deep neural network(DNN)is a superior method for processing nonlinear and massive data by adjusting the amount of neurons and hidden *** study adopted DNN to forecast ore production using truck haulage information and weather conditions at open-pit mines as training *** the prediction models were built,principal component analysis(PCA)was employed to reduce the data dimensionality and eliminate the multicollinearity among highly correlated input *** verify the superiority of DNN,three ANNs containing only one hidden layer and six traditional ML models were established as benchmark *** DNN model with multiple hidden layers performed better than the ANN models with a single hidden *** DNN model outperformed the extensively applied benchmark models in predicting ore *** can provide engineers and researchers with an accurate method to forecast ore production,which helps make sound budgetary decisions and mine planning at open-pit mines.

关键词： Oil sands production Open-pit mining Deep learning Principal component analysis(PCA) Artificial neural network Mining engineering

Multi-objective optimization and evaluation of supercritical CO_(2) Brayton cycle for nuclear power generation

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Nuclear Science and techniques 2024年第2期35卷 183-209页

作者： Guo-Peng Yu Yong-Feng Cheng na Zhang Ping-Jian Ming Sino-French Institute of Nuclear Engineering and technology Sun Yat-Sen UniversityZhuhai 519082China School of Civil Engineering and Architecture East China Jiaotong UniversityNanchang 330013China

the supercritical CO_(2) Brayton cycle is considered a promising energy conversion system for Generation IV reactors for its simple layout,compact structure,and high cycle *** models of four Brayton cycle layouts are developed in this study for different reactors to reduce the cost and increase the thermohydraulic performance of nuclear power generation to promote the commercialization of nuclear *** analysis,multi-objective optimizations,and four decision-making methods are applied to obtain each Brayton scheme’s optimal thermohydraulic and economic *** show that for the same design thermal power scale of reactors,the higher the core’s exit temperature,the better the Brayton cycle’s thermo-economic *** the four-cycle layouts,the recompression cycle(RC)has the best overall performance,followed by the simple recuperation cycle(SR)and the intercooling cycle(IC),and the worst is the reheating cycle(RH).However,RH has the lowest total cost of investment(C_(tot))of$1619.85 million,and IC has the lowest levelized cost of energy(LCOE)of 0.012$/(kWh).the nuclear Brayton cycle system’s overall performance has been improved due to *** performance of the molten salt reactor combined with the intercooling cycle(MSR-IC)scheme has the greatest improvement,with the net output power(W_(net)),thermal efficiencyη_(t),and exergy efficiency(η_(e))improved by 8.58%,8.58%,and 11.21%,*** performance of the lead-cooled fast reactor combined with the simple recuperation cycle scheme was optimized to increase C_(tot) by 27.78%.In comparison,the internal rate of return(IRR)increased by only 7.8%,which is not friendly to investors with limited *** the nuclear Brayton cycle,the molten salt reactor combined with the recompression cycle scheme should receive priority,and the gas-cooled fast reactor combined with the reheating cycle scheme should be considered carefully.

关键词： Supercritical CO_(2)Brayton cycle Nuclear power generation thermo-economic analysis Multi-objective optimization Decision-making methods

the Adjustment Analysis Method of the Active Surface Antenna Based on Convolutional Neural Network

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Research in Astronomy and Astrophysics 2024年第6期24卷 294-306页

作者： You Ban Shang Shi na Wang Qian Xu Shufei Feng School of Mechanical Engineering Xinjiang UniversityUrumqi 830017China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China School of Mechanical Engineering Dongguan University of TechnologyDongguan 523808China

Active surface technique is one of the key technologies to ensure the reflector accuracy of the millimeter/submillimeter wave large reflector *** antenna is complex,large-scale,and high-precision equipment,and its active surfaces are affected by various factors that are difficult to comprehensively deal *** this paper,based on the advantage of the deep learning method that can be improved through data learning,we propose the active adjustment value analysis method of large reflector antenna based on deep *** method constructs a neural network model for antenna active adjustment analysis in view of the fact that a large reflector antenna consists of multiple panels spliced *** on the constraint that a single actuator has to support multiple panels(usually 4),an autonomously learned neural network emphasis layer module is designed to enhance the adaptability of the active adjustment neural network *** classical 8-meter antenna is used as a case study,the actuators have a mean adjustment error of 0.00252 mm,and the corresponding antenna surface error is0.00523 *** active adjustment result shows the effectiveness of the method in this paper.

关键词： techniques:radar astronomy telescopes methods:analytical methods:numerical

Boosted sustained-release with iron-based MOF-derived mesoporouscarbon-spheres as a nitroimidazole drugs carrier

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Particuology 2024年第3期86卷 269-280页

作者： Danping Wu Jiaying Zou Junyi Chen Yan Li na Ma Wei Dai College of Chemistry and Materials Science Zhejiang Normal UniversityJinhua321004China College of Life Sciences Zhejiang Normal UniversityJinhua321004China College of Geography and Environmental Sciences Zhejiang Normal UniversityJinhua321004China

Metal-organic framework(MoF)with a buildable internal structure has aroused great interest focus as self-sacrificing precursors of porous carbon(PC).However,as a drug carrier,the MOF-derived PC developed thus far are generally composed of irregular powder shape due to their crystalline nature,which consequently causing the cerebral infarction,cerebral thrombosis,and other blood *** this article,we propose a novel approach to constructing amorphous carbon microspheres(AcMs)by dis-torting the topological network through hydrothermal treatment precursors of MIL-101(Fe).then,a distinctive MIL-101(Fe)-derived spherical porous carbons(MSPC)is achieved through high temperature calcination toward *** of the glucose initial concentration and hydrothermal treatment time on the sphericity of the as-prepared mesoporous MsPC were investigated in *** the loading capacities and sustained-release performances of nitroimidazole drugs over MsPC through simulation internal environment of human body at different pH values was systematically *** nitro-imidazole drugs loading rate and release time of MsPC are 10% and 17 h under preferred ***,the MSPC exhibited very low toxicity on Hela cells and 293t cells at the concentrations tested(10-800μg mL^(-1)).this study,therefore,supports the potential of the mesoporous carbon spheres as a carrierfor nitroimidazole drug delivery.

关键词： Ornidazole Metronidazole Carbon spheres Sustained-release performance Biocompatibility

Effectiveness of magnetic resonance imaging and spiral computed tomography in the staging and treatment prognosis of colorectal cancer

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 2135-2144页

作者： Lu-na Bai Lu-Xian Zhang Department of Radiology Zhongshan Hospital Xiamen UniversityXiamen 361004Fujian ProvinceChina

BACkGROUND Colorectal cancer(CRC)is a prevalent cancer type in clinical settings;its early signs can be difficult to detect,which often results in late-stage diagnoses in many *** early detection and diagnosis of CRC are crucial for improving treatment success and patient survival ***,imaging techniques have been hypothesized to be essential in managing CRC,with magnetic resonance imaging(MRI)and spiral computed tomography(SCt)playing a significant role in enhancing diagnostic and treatment *** to explore the effectiveness of MRI and SCt in the preoperative staging of CRC and the prognosis of laparoscopic *** Ninety-five individuals admitted to Zhongshan Hospital Xiamen University underwent MRI and SCt and were diagnosed with *** precision of MRI and SCt for the presurgical classification of CRC was assessed,and pathological staging was used as a *** operating characteristic curves were used to evaluate the diagnostic efficacy of blood volume,blood flow,time to peak,permeability surface,blood reflux constant,volume transfer constant,and extracellular extravascular space volume fraction on the prognosis of patients with *** Pathological biopsies confirmed the following CRC stages:23,23,32,and 17 at t1,t2,t3,and t4,*** were 39 cases at the N0 stage,22 at N1,34 at N2,44 at M0 stage,and 51 at *** pathological findings as the benchmark,the combined use of MRI and SCt for preoperative tNM staging in patients with CRC demonstrated superior sensitivity,specificity,and accuracy compared with either modality alone,with a statistically significant difference in accuracy(Pting characteristic curve analysis revealed the predictive values for laparoscopic treatment prognosis,as indicated by the areas under the curve for blood volume,blood flow,time to peak,and permeability surface,blood reflux constant,volume transfer constant,and extracellular extravascular space volu

关键词： Magnetic resonance imaging Spiral computed tomography Colorectal cancer Prognosis Receiver operating characteristic curve Retrospective study

Efficacy and safety of electroacupuncture for insomnia:A systematic review and meta-analysis

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Journal of Integrative Medicine 2024年第4期22卷 459-472页

作者： Han-yu Xu Lin-na Wu Yuan Zhang te Ba Xiao-feng Zhao Acupuncture and Moxibustion Department First Teaching Hospital of Tianjin University of Traditional Chinese MedicineTianjin 300193China national Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion Tianjin 300193China

Background:Electroacupuncture is often used to treat ***:to evaluate the efficacy and safety of electroacupuncture for *** strategy:Databases including PubMed,Cochrane Library,Embase,Web of Science,Chinese Biomedical Literature Database,China national knowledge Infrastructure,Wanfang Data and VIP Fulltext e-Journals Database were searched up to January 15,*** criteria:Randomized clinical trials were included if they compared the clinical efficacy and safety of electroacupuncture with sham acupuncture,no treatment or usual care (UC) and general *** extraction and analysis:the full texts of the studies were reviewed to remove ineligible *** extracted data included authors,publication year,diagnostic criteria,sample size,population characteristics,interventions and *** above steps were performed independently by two reviewers and the data were cross ***15.0 software was used to analyze the extracted outcome *** continuous data (Pittsburgh Sleep Quality Index[PSQI]score and Insomnia Severity Index score),weighted mean difference (WMD) was calculated and 95% confidence interval (CI) was reported when the same scale was *** dichotomous variables (clinical response rate and adverse events),a meta-analysis was performed using risk ratio (RR) as the effect ***:thirty-one trials with 2226 subjects were *** meta-analysis suggested that electroacupuncture was more effective in improving insomnia compared with the control group (sham acupuncture,no treatment,UC and general acupuncture)(RR=1.21;95 CI:[1.16,1.27]),significantly reducing the PSQI score in insomnia patients after treatment and at follow-up (WMD=-3.23;95%CI:[-4.29,-2.17];Pthere was no significant difference in the incidence of adverse events between the EA and control groups (sham acupuncture and no treatment or ***=1.48;95%CI:[0.91,2.40];P=0.117).In addition,the regression results revealed t

关键词： Electroacupuncture Insomnia Systematic review Meta-analysis

ti_(3)C_(2)t_(x)MXene wrapped,carbon-coated porous Si sheets for improved lithium storage performance

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Chinese Chemical Letters 2024年第2期35卷 617-621页

作者： Hui Cheng Yueming Liu Zhongling Cheng Xianying Wang na Huang Haijiao Zhang Institute of nanochemistry and nanobiology School of Environmental and Chemical EngineeringShanghai UniversityShanghai 200444China Shanghai key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China Energy Materials Research Center AG Hydrogen Materials & Devices CAS Key Laboratory of Materials for Energy ConversionShanghai Institute of CeramicsChinese Academy of Sciences (SICCAS)Shanghai 200050China

Si-based materials have shown great potential as lithium-ion batteries(LIBs)anodes due to their natural reserves and high theoretical ***,the large volume changes during cycles and poor conductivity of Si lead to rapid capacity decay and poor cycling stability,ultimately limiting their commercial ***,we have skillfully utilized the microporous MCM-22 zeolite as the unique silicon source to produce porous Si(pSi)sheets by a simple magnesiothermic reduction,followed by a carbon coating and further ti_(3)C_(2)t_(x)MXene assembly,obtaining the ternary pSi@NC@tNSs *** the design,porous Si sheets provide more active sites and shorten Li-ion transport paths for electrochemical *** N-doped carbon(NC)layer serves as a bonding layer to couple pSi and ti_(3)C_(2)t_(x).the conductive network formed by 2D ti_(3)C_(2)t_(x)and medium NC layer effectively enhances the overall charge transport of the electrode material,and helps to stabilize the electrode ***,the as-made pSi@NC@tNSs anode delivers an improved lithium storage performance,exhibiting a high reversible capacity of 925 mAh/g at 0.5 A/g after 100 *** present strategy provides an effective way towards high-performance Si-based anodes for LIBs.

关键词： Si anodes ti_(3)C_(2)ti_(x)MXene Porous structure Interfacial assembly Lithium-ion batteries

不同暗瞳直径屈光不正患者ICL植入术后视觉质量比较

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中华眼视光学与视觉科学杂志 2024年第5期26卷 340-346页

作者：尹娜周娜陈晓蓓暨南大学附属东莞爱尔眼科医院东莞

目的: 比较不同暗瞳直径下有晶状体眼后房型人工晶状体(ICL)植入术后的视觉质量。方法: 前瞻性临床研究。连续选取2022年10月至2023年6月在东莞爱尔眼科医院屈光手术中心行ICL V4c植入手术的屈光不正患者90例(90眼)。根据暗瞳直径分为3... 详细信息

目的: 比较不同暗瞳直径下有晶状体眼后房型人工晶状体(ICL)植入术后的视觉质量。方法: 前瞻性临床研究。连续选取2022年10月至2023年6月在东莞爱尔眼科医院屈光手术中心行ICL V4c植入手术的屈光不正患者90例(90眼)。根据暗瞳直径分为3组:A组≤6.5 mm, B组>6.5～7.3 mm, C组>7.3 mm, 每组均30例(30眼), 均选取右眼数据。观察并记录患者术前、术后3个月的裸眼视力(UCVA)、等效球镜度(SE)。使用OPD-ScanⅢ像差分析仪测量4 mm和7 mm瞳孔直径下的客观视觉质量参数, 包括全眼高阶像差的Zenike多项式的均方根(RMS)值、斯特列尔比(SR)、调制传递函数(MtF)曲线与正常眼区域之间的比例(AR), 其中全眼高阶像差包括总高阶像差(HOAs)、彗差、三叶草像差、球差。组内手术前后参数比较采用配对t检验或秩和检验, 组间数据比较采用单因素方差分析或kruskal-Wallis检验。术前暗瞳直径与AR的相关性采用Pearson相关检验分析, 与余参数的相关性分析采用Spearman秩相关检验。结果: A、B、C组组内术后3个月的UCVA、SE均较术前改善(均P0.05);在7 mm瞳孔直径下, A组术后HOAs、三叶草像差与术前差异有统计学意义(Z=-2.37, P=0.018;t=-2.59, P=0.015), B组和C组术后HOAs、彗差、三叶草像差、球差与术前比较差异均有统计学意义(均P0.05)。在4 mm和7 mm瞳孔直径下, 术后3个月3组组内SR、AR均较术前明显升高(均P0.05)。在4 mm瞳孔直径下, 术后的视觉质量参数与术前暗瞳直径均无相关性(均P>0.05);在7 mm瞳孔直径下SR、AR与术前暗瞳直径呈负相关(r=-0.25, P=0.018;r=-0.32, P=0.002), HOAs、彗差、球差与术前暗瞳直径呈正相关(r=0.70、0.61、0.80, 均P<0.001)。结论 :ICL植入术后早期明、暗环境下视觉质量均较术前改善。暗视环境下, HOAs、彗差、球差、SR、AR与术前暗瞳直径有关, 三叶草像差与术前暗瞳直径无关且手术前后变化最小。

关键词：有晶状体眼人工晶状体植入术瞳孔视觉质量光学区直径

Strong-coupling superconductivity with tc above 70 k in Be-decorated monolayer t-graphene

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 99-105页

作者： Liu Yang Peng-Fei Liu Hao-Dong Liu Ya-Ping Li na Jiao Hong-Yan Lu Bao-tian Wang Ping Zhang School of Physics and Physical Engineering Qufu Normal UniversityQufu 273165China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Spallation Neutron Source Science Center Dongguan 523803China Institute of Applied Physics and Computational Mathematics Beijing 100088China

Using first-principles calculations,we predict a new type of two-dimensional(2D)beryllium(Be)-decorated t-graphene named BeC_(2),where Be atoms are inserted into C–C bonds linking the carbon tetrarings of *** band structure shows that BeC_(2)is metallic,thus,the possible phonon-mediated superconductivity is explored based on the Eliashberg *** calculated electron-phonon coupling(EPC)constantλis up to 4.07,and the corresponding superconducting critical temperature(tc)is 72.1 k,approaching the liquid nitrogen *** reason for the high tc is the strong *** it is proved to be an anisotropic single-gap superconductor by analyzing the superconducting gap?kof BeC_(2).the electronic susceptibility calculation shows strong nesting effect in BeC_(2).Since rare 2D superconductors show such a strong EPC constantλwhich originates from the coupling between electrons in C-pzorbital and in-plane vibrations of Be and C atoms,the predicted BeC_(2)provides a new platform for investigating strong EPC 2D superconductor.

关键词： two-dimensional carbon-based superconductor electron-phonon coupling strong coupling high superconducting critical temperature