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Integrating Weather Conditions to Forecast the Electricity Price in Belgium Market: A Novel Mixed-Frequency Machine Learning Algorithm

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Journal of Systems Science & Complexity 2024年

作者： DU Xiaoxu cai yi TANG Zhenpeng School of Economics and Management Fuzhou University School of Economics and Management Fujian Agriculture and Forestry University

The fluctuations in weather conditions,such as temperature and wind speed,can impact the process of solar and wind power generation,thereby influencing electricity ***-time price settlement requires a higher resolution than daily frequency to forecast electricity *** research proposes a novel mixed-frequency model to address the issue of frequency inconsistency problem between electricity prices and related factors,and successfully applies it to Belgium electricity price ***,the RU-MIDAS method is used to analyze the dynamic impact of weather conditions on ***,RU-MIDAS is combined with machine learning algorithms to predict the *** results of error metrics and MCS test indicate that humidity can improve the prediction accuracy of all four *** prediction ability of wind gusts is comparable to that of the highest price;the former helps predict the last two subsequences,while the latter improves the prediction accuracy of the first two *** can only help predict the fourth electricity price series,and the forecasting ability of weather factors is consistent with the order of feature importance.

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Primordial black hole mass functions as a probe of cosmic origin

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 164-171页

作者： yi-Fu cai Chengfeng Tang Geyu Mo Sheng-Feng Yan Chao Chen Xiao-Han Ma Bo Wang Wentao Luo Damien A.Easson Antonino Marcianò Deep Space Exploration Laboratory/School of Physical Sciences University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory for Researches in Galaxies and Cosmology/Department of Astronomy School of Astronomy and Space ScienceUniversity of Science and Technology of ChinaHefei 230026China Istituto Nazionale di Fisica Nucleare(INFN) Sezione di MilanoMilano 20146Italy DiSAT Universitàdegli Studi dell'InsubriaComo 22100Italy Jockey Club Institute for Advanced Study The Hong Kong University of Science and TechnologyHong KongChina Department of Physics Arizona State UniversityTempe 85287-1504USA Department of Physics&Center for Field Theory and Particle Physics Fudan UniversityShanghai 200433China Laboratori Nazionali di Frascati INFN Via Enrico Fermi 541 Frascati(Roma)00044Italy INFN sezione Roma Tor Vergata Rome I-00133Italy School of Physics University of Electronic Science and Technology of ChinaChengdu11731China

We discuss a novel window to probe the origin of our universe via the mass functions of primordial black holes(PBHs).The mass functions of PBHs are simply estimated using the conventional Press-Schechter formalism for two paradigms of cosmic origin,including inflationaryΛCDM and bounce *** standard inflationaryΛCDM model cannot generate an appreciable number of massive PBHs;however,non-trivial inflation models with blue-tilted power spectra at small scales and matter bounce cosmology provide formation mechanisms for heavy PBHs,which in turn,may seed the observed supermassive black holes(SMBHs).By fitting the SMBH mass functions at high redshift(z~6)derived from Sloan Digital Sky Survey(SDSS)and Canada-France High-z Quasar Survey(CFHQS)quasars,for two paradigms of cosmic origin,we derive constraints on the PBH density fraction fPBHat z~6 and the characteristic mass M_(★),with the prior assumption that all SMBHs stem from *** demonstrate that this newly proposed procedure,relying on astronomical measurements that utilize deep-field surveys of SMBHs at high redshift,can be used to constrain models of cosmic ***,although not the main focus of this paper,we evolve the mass function from z~6 to z~0 through an assumption of 3×10^(8)-year Eddington’s accretion,and give a rough estimation of fPBHat z~0.

关键词： origin cosmic massive

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Differences and Correlations of Morphological and Hemodynamic Parameters between Anterior Circulation Bifurcation and Side-wall Aneurysms

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Current Medical Science 2024年第2期44卷 391-398页

作者： Kai-kai GUO Chang-ya LIU Gao-hui LI Jian-ping XIANG Xiao-chang LENG yi-ke cai Xue-bin HU Department of Neurosurgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Department of Emergency Longhua HospitalShanghai University of Traditional Chinese MedicineShanghai 200032China Artery Flow Technology Co. Ltd.Hangzhou 310051China

Objective:The objective of this research was to explore the difference and correlation of the morphological and hemodynamic features between sidewall and bifurcation aneurysms in anterior circulation arteries,utilizing computational fluid dynamics as a tool for ***:In line with the designated inclusion criteria,this study covered 160 aneurysms identified in 131 patients who received treatment at Union Hospital of Tongji Medical College,Huazhong University of Science and Technology,China,from January 2021 to September *** follow-up digital subtraction angiography(DSA)data,these cases were classified into two distinct groups:the sidewall aneurysm group and the bifurcation aneurysm *** and hemodynamic parameters in the immediate preoperative period were meticulously calculated and examined in both groups using a three-dimensional DSA reconstruction ***:No significant differences were found in the morphological or hemodynamic parameters of bifurcation aneurysms at varied locations within the anterior ***,pronounced differences were identified between sidewall and bifurcation aneurysms in terms of morphological parameters such as the diameter of the parent vessel(Dvessel),inflow angle(θF),and size ratio(SR),as well as the hemodynamic parameter of inflow concentration index(ICI)(P0.5,P<0.001).Conclusions:The significant differences in certain morphological and hemodynamic parameters between sidewall and bifurcation aneurysms emphasize the importance to contemplate variances in threshold values for these parameters when evaluating the risk of rupture in anterior circulation *** it is a bifurcation or sidewall aneurysm,these disparities should be *** morphological parameter SR has the potential to be a val

关键词： sidewall bifurcation unruptured aneurysms computational fluid dynamics

Hydromassage of macular hole edges for large and persistent full-thickness macular holes

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 551-557页

作者： yi cai Wen-Bo Liu Duo Wei Xun Deng Xiao-Xin Li Ming-Wei Zhao Xuan Shi Jian-Hong Liang Department of Ophthalmology Peking University People’s HospitalBeijing 100044China Eye Diseases and Optometry Institute Beijing 100044China Beijing Key Laboratory of Diagnosis and Therapy of Retinal and Choroid Diseases Beijing 100044China College of Optometry Peking University Health Science CenterBeijing 100044China Xiamen Eye Center of Xiamen University Xiamen 361102Fujian ProvinceChina Department of Ophthalmology the Second Hospital of Lanzhou UniversityLanzhou 730030Gansu ProvinceChina

●AIM:To introduce the macular hole(MH)hydromassage technique as a potentially beneficial approach for the treatment of large or persistent MH.●METHODS:This retrospective observational case series comprised 16 consecutive patients(17 eyes)diagnosed with *** criteria involved a hole aperture diameter larger than 600μm or the presence of an unclosed MH larger than 600μm following the previous *** MH repair procedures were administered in all cases,involving the manipulation and aspiration of the hole margin through the application of water flow with a soft-tip flute needle.A comprehensive assessment was conducted for each case before and after surgery,and optical coherence tomography(OCT)images were captured at every follow-up point.●RESULTS:The mean preoperative aperture diameter was 747±156μm(range 611-1180μm),with a mean base diameter of 1390±435μm(range 578-2220μm).Following surgery,all cases achieved complete anatomical closure of MH,with 13 cases(76.5%)exhibiting type 1 closure and 4 cases(23.5%)demonstrating type 2 *** significant differences were observed in the preoperative OCT variables between the two closure *** with type 1 closure showed a significantly improved visual acuity(0.70±0.10,range 0.50-0.80)compared to those with type 2 closure(0.90±0.12,range 0.80-1.00,P=0.014).●CONCLUSION:The MH hydromassage technique demonstrates promising results,achieving acceptable closure rates in cases of large or persistent *** technique may serve as an effective adjunctive maneuver during challenging MH surgery.

关键词： macular hole large macular hole persistent macular hole optical coherence tomography surgical technique hydromassage

Rapidly growing primordial black holes as seeds of the massive high-redshift JWST Galaxies

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Science China(Physics,Mechanics & Astronomy) 2024年

作者： Guan-Wen Yuan Lei Lei Yuan-Zhu Wang Bo Wang yi-ying Wang Chao Chen Zhao-Qiang Shen yi-Fu cai yi-Zhong Fan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of Sciences School of Astronomy and Space Science University of Science and Technology of China Institute of High Energy Physics Chinese Academy of Sciences Deep Space Exploration Laboratory/Department of Astronomy School of Physical SciencesUniversity of Science and Technology of China Jockey Club Institute for Advanced Study The Hong Kong University of Science and Technology

A group of massive galaxies at redshifts of z 7 have been recently detected by the James Webb Space Telescope (JWST),which were unexpected to form at such an early time within the standard Big Bang *** this work,we propose that this puzzle can be explained by the presence of some primordial black holes (PBHs) with a mass of～1000M⊙.These PBHs act as seeds for early galaxy formation with masses of～108-1010M⊙at high redshift,hence accounting for the JWST *** use a hierarchical Bayesian inference framework to constrain the PBH mass distribution models,and find that the Lognormal model with the Mc～750M⊙is preferred over other *** rapidly growing BHs are expected to have strong radiation and may appear as high-redshift compact objects,similar to those recently discovered by *** we focused on PBHs in this work,the bound on the initial mass of the seed black holes remains robust even if they were formed through astrophysical channels.

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聂景孺《樱花馆日本诗话》考论

中国文学研究 2024年第3期 100-108页

作者：蔡毅南山大学外国语学部日本名古屋4668673

聂景孺的《樱花馆日本诗话》是中国诗话史上唯一一部关于日本汉诗的专论。作者1914年留学日本时,收集了117名日本汉诗人的作品247首,74联,分别录入110则诗话,并加以品评。本文对该书的作者身世、全书构成、资料来源以及编撰特色做了全... 详细信息

聂景孺的《樱花馆日本诗话》是中国诗话史上唯一一部关于日本汉诗的专论。作者1914年留学日本时,收集了117名日本汉诗人的作品247首,74联,分别录入110则诗话,并加以品评。本文对该书的作者身世、全书构成、资料来源以及编撰特色做了全面考察,指出作者为中国读者展示了一幅明治汉诗坛丰富多彩的画卷,但作品采纳较为随意,审美倾向较为保守,特别是对所收诗作擅自做了大量改动,却从未明言,这一点须加注意。

关键词：聂景孺《樱花馆日本诗话》明治汉诗擅自改动

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Development of a competitive array for discriminative determination of amphenicols in egg based on ribosomal protein L16

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Food Quality and Safety 2024年第1期8卷 105-114页

作者：才艺马宁吴宁鹏王建平 College of Veterinary Medicine Hebei Agricultural UniversityBaodingChina Henan Institute of Veterinary Drug and Feed Control ZhengzhouChina

Objective:Amphenicols(chloramphenicol,thiamphenicol and forfenicol)can cause aplastic anaemia and other severe side effects to consumers;therefore,it is necessary to inspect their residues in foods of animal ***,there has been no report on the use of amphenicols receptor for the determination of their residues,and none of the previously reported immunoassays for amphenicols can differentiate the specifc *** and Methods:In this study,the ribosomal protein L16 of Escherichia coli was frst expressed,and its intermolecular interaction mechanisms with the three amphenicols was studied using the molecular docking *** protein was then combined with three enzymelabelled conjugates to develop a direct competitive array on microplate for determination of the three drugs in ***:Due to the use of principal component analysis to analyse the data,this method could discriminate the three drugs in the range 0.1–10 ng/mL,and the limits of detection for the three drugs were in the range of 0.0002–0.0009 ng/*** analysis results for the unknown egg samples were consistent with a liquid chromatography–tandem mass spectrometry method,and the method performances were superior to the previous immunoassays for ***:This is the frst paper reporting the use of ribosomal protein L16 to develop a competitive array for discriminative determination of amphenicols in food samples.

关键词： Amphenicols ribosomal protein L16 recognition mechanism competitive array discriminative determination egg.

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线性化改进物质点法的颗粒流仿真

复旦学报（自然科学版） 2024年第2期63卷 216-229,I0002页

作者：蔡翼黄骏复旦大学航空航天系上海200433

作为一种新近发展出的无网格法,物质点法综合了基于网格方法的准确性与计算效率,以及无网格法对多种极端情境的适应性,因此该方法对采取连续介质模型的颗粒流数值计算等大变形问题十分有效。为提高物质点法对于颗粒流的计算效率,本文对... 详细信息

作为一种新近发展出的无网格法,物质点法综合了基于网格方法的准确性与计算效率,以及无网格法对多种极端情境的适应性,因此该方法对采取连续介质模型的颗粒流数值计算等大变形问题十分有效。为提高物质点法对于颗粒流的计算效率,本文对物质点法进行了线性化改进并基于改进算法给出了若干算例。以物质点法的背景网格的结构化特点以及Courant-Friedrichs-Lewy(CFL)条件为基础,改进了自然坐标系到整体坐标系的求解过程,并使用改进的物质点法对颗粒流的颗粒堆坍塌、筒仓排出以及曲面上颗粒流对半球体的碰撞等算例进行了计算。在计算精度损失较小的情况下,提高了物质点法求解颗粒流问题的效率,验证了此改进方法的有效性与稳定性。

关键词：颗粒流物质点法无网格法连续介质模型

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厚松散层矿区开采沉陷拉伸区域土体内部变形演化规律研究——以淮北孙疃煤矿为例

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煤炭科学技术 2024年第8期52卷 36-49页

作者：蔡毅沈华章黄厚旭严家平蔡国军蔡永祥杨博孙斌杨安徽建筑大学土木工程学院安徽合肥230601 安徽建筑大学安徽省智能地下探测技术研究院安徽合肥230601 安徽理工大学空间信息与测绘工程学院安徽淮南232001 安徽理工大学地球与环境学院安徽淮南232001

为了研究厚松散层矿区开采沉陷拉伸区域相应土体内部变形演化规律,针对淮北孙疃煤矿10111,沿垂直于工作面推进方向,于拟采空区地表投影区域外侧(拉伸区域)以60 m间隔由近及远布设1~3号竖向钻孔;采煤沉陷过程中基于光纤(1号钻孔)、测斜仪... 详细信息

为了研究厚松散层矿区开采沉陷拉伸区域相应土体内部变形演化规律,针对淮北孙疃煤矿10111,沿垂直于工作面推进方向,于拟采空区地表投影区域外侧(拉伸区域)以60 m间隔由近及远布设1~3号竖向钻孔;采煤沉陷过程中基于光纤(1号钻孔)、测斜仪(2~3号钻孔)技术开展钻孔变形监测;将煤炭开采引发移动的上覆岩层与松散层所占区域视为变形区,并引入任意厚度地层移动角的概念,分析开采沉陷拉伸区域相应松散层变形演化特征。结果表明:1号钻孔发生应变的最大孔深约157 m,且钻孔深部较浅部先达到活跃期;2、3号钻孔孔口最终累计水平位移量分别为129.8 mm和99.4 mm,最大位移深度分别约为108 m和75 m;2、3号钻孔监测范围内地层从下至上均可分为稳定段、变形区下段、中段与上段;2、3号钻孔从下至上水平位移量总体分布较均匀,每米深钻孔的平均水平位移量分别约为1.2 mm和1.3 mm;2、3号钻孔变形区下段均先于上段达到活跃期,且变形区下段稳定后上段仍有微弱变形;松散层内一定厚度地层,其地层移动角随地层深度的增加而增加,松散层变形区下边界的深度h随着与工作面水平距离l的增加而减小,h与l满足指数函数关系。

关键词：厚松散层矿区拉伸区域土体内部变形光纤监测钻孔测斜

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