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Cost-Sensitive Dual-Stream Residual Networks for Imbalanced Classification

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Computers, Materials & Continua 2024年第9期80卷 4243-4261页

作者： Congcong Ma Jiaqi mi Wanlin Gao Sha Tao College of Information and Electrical Engineering China Agricultural UniversityBeijing100083China Key Laboratory of Agricultural Informatization Standardization Ministry of Agriculture and Rural AffairsChina Agricultural UniversityBeijing100083China

Imbalanced data classification is the task of classifying datasets where there is a significant disparity in the number of samples between different *** task is prevalent in practical scenarios such as industrial fault diagnosis,network intrusion detection,cancer detection,*** imbalanced classification tasks,the focus is typically on achieving high recognition accuracy for the minority ***,due to the challenges presented by imbalanced multi-class datasets,such as the scarcity of samples in minority classes and complex inter-class relationships with overlapping boundaries,existing methods often do not perform well in multi-class imbalanced data classification tasks,particularly in terms of recognizing minority classes with high ***,this paper proposes a multi-class imbalanced data classification method called CSDSResNet,which is based on a cost-sensitive dualstream residual ***,to address the issue of limited samples in the minority class within imbalanced datasets,a dual-stream residual network backbone structure is designed to enhance the model’s feature extraction ***,considering the complexities arising fromimbalanced inter-class sample quantities and imbalanced inter-class overlapping boundaries in multi-class imbalanced datasets,a unique cost-sensitive loss function is *** loss function places more emphasis on the minority class and the challenging classes with high interclass similarity,thereby improving the model’s classification ***,the effectiveness and generalization of the proposed method,CSDSResNet,are evaluated on two datasets:‘DryBeans’and‘Electric Motor Defects’.The experimental results demonstrate that CSDSResNet achieves the best performance on imbalanced datasets,with macro_F1-score values improving by 2.9%and 1.9%on the two datasets compared to current state-of-the-art classification methods,***,it achieves the highest precision in single-class r

关键词： Deep learning imbalanced data classification fault diagnosis cost-sensitivity

Experimental study on out-of-plane seismic performance of precast composite sidewalls of utility tunnel with grouting-sleeve joints

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Underground Space 2024年第3期16卷 1-17页

作者： Zilan Zhong Guangfan Li Jinqiang Li Jiaxu Shen mi Zhao Xiuli Du Key Laboratory of Urban Security and Disaster Engineering of ministry of Education Beijing University of TechnologyBeijing 100124China

The precast composite reinforced concrete wall with the advantages of fewer joints,superior impermeability and rapid construction provides an efficient and environmental friendly alternative in the construction of underground utility tunnels in the last few *** investigate the seismic performance of precast concrete composite walls of utility tunnels with grouting-sleeve connection under out-ofplane loads,a series of quasi-static cyclic tests were performed on the full-scale sidewall specimens with different axial compression ratios in this *** experimental results including the failure modes,crack distributions,and the influence of different connections on the out-of-plane seismic performance of precast concrete composite wall were carefully examined and compared with those from the cyclic tests of the cast-in-place sidewalls of the utility *** test results show that the seismic performance of the precast concrete composite sidewall specimen,such as the hysteresis curves,the ultimate bearing capacity,stiffness degradation pattern and the ductility ratio,is basically the same as that of the cast-in-place specimen,indicating that the seismic performance of the prefabricated structure is equivalent to that of the cast-in-place ***,the grouting-sleeves of the joints can effectively transfer the reinforcement stress until the failure of the precast concrete composite sidewall specimens,which exhibits excellent out-of-plane ductility and serviceability.

关键词： Precast concrete composite walls Cyclic response Seismic performance Grouting sleeve Failure mechanism

Surface-state controlled synthesis of hydrophobic and hydrophilic carbon dots

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Nano Research 2024年第5期17卷 4391-4399页

作者： Chan Wang Yuan Fang mi Zhang Huan Zhuo Qijun Song Han Zhu Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxi 214122China Jiangsu Snow Leopard Household Chemical Co. Ltd.Wuxi 214400China

It is of great significance to synthesize carbon dots(CDs)with desirable hydrophilicity for the ever-growing application of CDs in different *** this study,the hydrophilic and hydrophobic CDs were facilely prepared by solvothermal treatment of o-dihydroxybenzene and urea in N,N-dimethylformamide(DMF).Optimization experiments revealed that the solvothermal temperature has a great impact on the surface states of the *** hydrophobic CDs with a contact angle of 110.7°was obtained at 200℃.The structural and optical characterizations,along with theoretical calculations elucidated that the lipophilic nature of the CDs was resulting from the formation of polymer *** presence of extended conjugated sp^(2)-domains and amino groups contributed to the red emission of the CDs synthesized at low reaction temperatures(160-200℃).With the further increase of solvothermal temperature,the hydrophobic CDs were gradually transformed to the hydrophilic state accompanying the blue shift of the fluorescence of the *** highly hydrophilic CDs with a contact angle of 25.9°were obtained at 240℃ due to the increased formation of hydrophilic functional groups on the surface of *** red emissive CDs exhibited a sensitive color and fluorescence response to ethanol content while the fluorescence of the blue emissive CDs remained *** combining the two kinds of CDs,a dual-emission sensor was constructed,which was successfully applied for the evaluation of the alcoholic strength in commercial Baijiu commodities in both fluorometric and colorimetric modes.

关键词： carbon dots surface chemistry hydrophilicity and hydrophobicity solvothermal temperature alcoholic strength evaluation

Imprinting at the KBTBD6 locus involves species-specific m ternal methylation and monoallelic expression in livestock animals

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Journal of Animal Science and Biotechnology 2024年第1期15卷 127-145页

作者： Jinsoo Ahn In-Sul Hwang mi-Ryung Park Seongsoo Hwang Kichoon Lee Department of Animal Sciences The Ohio State UniversityColumbusOH 43210USA Animal Biotechnology Division Rural Development AdministrationNational Institute of Animal ScienceJeonbuk 55365Republic of Korea Columbia Center for Translational Immunology Columbia University Irving Medical CenterColumbia UniversityNew YorkNY 10032USA Animal Welfare Research Team National Institute of Animal ScienceRDA1500Kongjwipatjwi‑roJeollabuk‑do 55365Republic of Korea

Background The primary differentially methylated regions(DMRs) which are maternally hypermethylated serve as imprinting control regions(ICRs) that drive monoallelic gene expression, and these ICRs have been investigated due to their implications in mammalian development. Although a subset of genes has been identified as imprinted, in-depth comparative approach needs to be developed for identification of species-specific imprinted genes. Here, we examined DNA methylation status and allelic expression at the KBTBD6 locus across species and tissues and explored potential mechanisms of *** Using whole-genome bisulfite sequencing and RNA-sequencing on parthenogenetic and normal porcine embryos, we identified a maternally hypermethylated DMR between the embryos at the KBTBD6 promoter Cp G island and paternal monoallelic expression of KBTBD6. Also, in analyzed domesticated mammals but not in humans, non-human primates and mice, the KBTBD6 promoter Cp G islands were methylated in oocytes and/or allelically methyl-ated in tissues, and monoallelic KBTBD6 expression was observed, indicating livestock-specific imprinting. Further analysis revealed that these Cp G islands were embedded within transcripts in porcine and bovine oocytes which coexisted with an active transcription mark and DNA methylation, implying the presence of transcription-dependent *** In this study, our comparative approach revealed an imprinted expression of the KBTBD6 gene in domesticated mammals, but not in humans, non-human primates, and mice which implicates species-specific evolution of genomic imprinting.

关键词： Differentially methylated region Domesticated mammal Imprinting KBTBD6 Parthenogenetic

Numerical Study on the Aerodynamic and Fluid−Structure Interaction of An NREL-5MW Wind Turbine

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China Ocean Engineering 2024年第3期38卷 363-378页

作者： ZHAO mi YU Wan-li WANG Pi-guang QU Yang DU Xiu-li Key Laboratory of Urban Security and Disaster Engineering of ministry of Education Beijing University of TechnologyBeijing 100124China State Key Laboratory of Bridge Engineering Safety and Resilience Beijing University of TechnologyBeijing 100124China

A 5-MW wind turbine has been modeled and analyzed for fluid-structure interaction and aerodynamic *** this study, a full-scale model of a 5-MW wind turbine is first developed based on a computational fluid dynamics(CFD) approach, in which the unsteady, noncompressible Reynolds Averaged Navier-Stokes(RANS) method is used. The main focus of the study is to analyze the tower shadow effect on the aerodynamic performance of the wind turbine under different inlet flow conditions. Subsequently, the finite element model is established by considering fluid/structure interactions to study the structural stress, displacement, strain distributions and flow field information of the structure under the uniform wind speed. Finally, the fluid-structure interaction model is established by considering turbulent wind and the tower shadow effect. The variation rules of the dynamic response of the one-way and two-way fluid-structure interaction(FSI) models under different wind speeds are analyzed, and the numerical calculation results are compared with those of the centralized mass model. The results show that the tower shadow effect and structural deformation are the main factors affecting the aerodynamic load fluctuation of the wind turbine, which in turn affects the aerodynamic performance and structural stability of the blades. The structural dynamic response of the coupled model shows significant similarity, while the structural displacement response of the former exhibits less fluctuation compared with the conventional centralized mass model. The one-way fluid-structure interaction(FSI)model shows a higher frequency of stress-strain and displacement oscillations on the blade compared with the two-way FSI model.

关键词： computational fluid dynamics methods(CFD) tower shadow effect aerodynamic performance fluidstructure interaction space flow field

Analytical Solution and Simplified Formula for Added Mass of Horizontal and Vertical Motions of Truncated Cylinders Under Earthquake Action

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China Ocean Engineering 2024年第1期38卷 54-67页

作者： WANG Pi-guang LYU Si-yu QU Yang ZHAO mi DU Xiu-li State Key Laboratory of Bridge Engineering Safety and Resilience Beijing University of TechnologyBeijing 100124China Key Laboratory of Urban Security and Disaster Engineering of ministry of Education Beijing University of Tech-nologyBeijing 100124China

This paper investigates the hydrodynamic characteristics of floating truncated cylinders undergoing horizontal and vertical motions due to earthquake excitations in the finite water *** governing equation of the hydrodynamic pressure acting on the cylinder is derived based on the radiation theory with the inviscid and incompressible *** governing equation is solved by using the method of separating variables and analytical solutions are obtained by assigning reasonable boundary *** analytical result is validated by a numerical model using the exact artificial boundary simulation of the infinite *** main variation and distribution characteristics of the hydrodynamic pressure acting on the side and bottom of the cylinder are analyzed for different combinations of wide-height and immersion *** added mass coefficient of the cylinder is calculated by integrating the hydrodynamic pressure and simplified formulas are proposed for engineering *** calculation results show that the simplified formulas are in good agreement with the analytical solutions.

关键词： earthquake hydrodynamic pressure truncated cylinder added mass simplified formula

Factors affecting length of stay according to bronchopulmonary dysplasia severity:a nationwide cohort study in Korea

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World Journal of Pediatrics 2024年第5期20卷 470-480页

作者： Hye mi Lee Jeongmin Shin Sae Yun Kim So Young Kim Department of Pediatrics College of MedicineThe Catholic University of KoreaSeoulRepublic of Korea Department of Pediatrics Yeouido St.Mary’s HospitalCollege of MedicineThe Catholic University of Korea1063-roYeongdeungpo-guSeoul07345Republic of Korea

Background Longer hospitalizations for preterm infants with bronchopulmonary dysplasia(BPD)delay developmental outcomes,increase the risk for hospital-acquired complications,and exert a substantial socioeconomic *** study aimed to identify factors associated with an extended length of stay(LOS)at different levels of severity of *** A cohort study was conducted using the Korean Neonatal Network registry of very low birth weight infants with BPD between 2013 and 2017 through retrospective *** A total of 4263 infants were diagnosed with *** mild BPD,infants requiring surgical treatment for patent ductus arteriosus needed a longer LOS[eadjustedβcoefficients(adjβ)1.041;95%confidence interval(CI):0.01–0.08]and hydrocephalus(eadjβ1.094;95%CI 0.01–0.17).In moderate BPD,infants administered steroids or with intraventricular hemorrhage required a longer LOS(eadjβ1.041;95%CI 0.00–0.07 and eadjβ1.271;95%CI 0.11–0.38,respectively).In severe BPD,infants with comorbidities required a longer LOS:pulmonary hypertension(eadjβ1.174;95%CI 0.09–0.23),administrated steroid for BPD(eadjβ1.116;95%CI 0.07–0.14),sepsis(eadjβ1.062;95%CI 0.01–0.11),patent ductus arteriosus requiring surgical ligation(eadjβ1.041;95%CI 0.00–0.08),and intraventricular hemorrhage(eadjβ1.016;95%CI 0.05–0.26).Additionally,the higher the clinical risk index score,the longer the LOS needed for infants in all *** The factors affecting LOS differed according to the severity of *** approaches to reducing LOS may be devised using knowledge of the various risk factors affecting LOS by BPD severity.

关键词： Bronchopulmonary dysplasia Length of stay Very low birth weight

Sustainable, thermoplastic and hydrophobic coating from natural cellulose and cinnamon to fabricate eco-friendly catering packaging

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Green Energy & Environment 2024年第5期9卷 927-936页

作者： Rumeng Xu Chunchun Yin Jingxuan You Jinming Zhang Qinyong mi Jin Wu Jun Zhang CAS Key Laboratory of Engineering Plastics Institute of ChemistryChinese Academy of Sciences(CAS)Beijing100190China University of Chinese Academy of Sciences Beijing100049China

Non-degradable polymers cause serious environmental pollution problem,such as the widely-used while unrecyclable coatings which signiﬁcantly affect the overall degradation performance of *** is imperative and attractive to develop biodegradable functional ***,we proposed a novel strategy to successfully prepare biodegradable,thermoplastic and hydrophobic coatings with high transparence and biosafety by weakening the interchain interactions between cellulose *** natural cellulose and cinnamic acid were as raw *** reducing the degree of polymerization(DP)of cellulose and regulating the degree of substitution(DS)of cinnamate moiety,the obtained cellulose cinnamate(CC)exhibited not only the thermalﬂow behavior but also good biodegradability,which solves the conﬂict between the thermoplasticity and biodegradability in cellulose-based *** glass transition temperature(T_(g))and thermalﬂow temperature(T_(f))of the CC could be adjusted in a range of 150–200℃ and 180–210℃,*** CC with DS<1.2 and DP≤100 degraded more than 60%after an enzyme treatment for 7 days,and degraded more than 80%after a composting treatment for 42 ***,CC had no toxicity to human epidermal cells even at a high concentration(0.5 mg mL^(-1)).In addition,CC could be easily fabricated into multifunctional coating with high hydrophobicity,thermal adhesion and high ***,after combining with cellophane and paperboard,CC coating with low DP and DS could be used to prepare fully-biodegradable heat-sealing packaging,art paper,paper cups,paper straws and food packaging boxes.

关键词： Thermoplastic coating Bio-degradable adhesive Natural products Cellulose Eco-friendly packaging

Global Spillovers of China's Monetary Policy

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China & World Economy 2024年第3期32卷 1-30页

作者： Wenni Lei Dongzhou Mei mi Zhang School of Economics Minzu University of ChinaChina School of International Trade and Economics Central University of Finance and EconomicsChina

Spillovers from China's monetary policy have become increasingly obvious with China's growing importance in the global economy and its close economic and trade ties with the *** study establishes a proxy structure vector autoregression model to investigate the magnitude and transmission channel of spillovers from China to global and regional economies,taking advantage of high-frequency changes in asset prices in the financial markets to identify monetary policy *** analysis reveals that China's monetary policy can affect the global economy by influencing international trade and commodity prices but there is no evidence of China's monetary policy affecting global financial *** in China's monetary policy can cause a decline in world output whereas expansion in monetary policy can support global trade and *** study also finds that the response of emerging Asian economies to China's monetary policy shock was nearly twice that of developed economies,while the transmission path did not *** results of this study are consistent with the stylized fact that China's monetary policy plays an important role in the global trade and commodity cycle,although it does not drive the global financial cycle.

关键词： China's monetary policy commodity prices external instruments global trade spillovers