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Microstructure and properties of LZQT600-3 HCCDIBs for plunger pump cylinder

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China Foundry 2024年第2期21卷 197-204页

作者： Chun-jie Xu yuan-ying Jin Dong Ma Zhen Zhao Jia-wei Qi Shang Sui Xiang-quan Wu Can Guo Zhong-ming Zhang Yong-hui liu Dan Shechtman School of Materials Science and Engineering Xi'an University of TechnologyXi'an 710048China Xi'an Shechtman Nobel Prize New Materials Institute Xi'an 710048China Tongchuan Huazhu Precision Technology Co. Ltd.Tongchuan 727100ShaanxiChina Faculty of Materials Science and Engineering Technion-Israel Insititue of TechnologyHaifa 3200003Israel

It is important to improve the comprehensive performance of the ductile iron bars(DIBs)for the cylinder block of the extra high pressure hydraulic plunger pump and accelerate the industrial *** this work,the LZQT600-3 DIBs with the diameter of 145 mm were prepared by the horizontal continuous casting(HCC)process,that is,LZQT600-3 *** microstructure and room temperature tensile properties of different sections[left-edge(surface layer),left-1/2R(left half of the radius),and the center of the HCCDIBs]were *** results show that the spheroidization of LZQT600-3 HCCDIBs matrix from the left-edge,left-1/2R to the center is at nodulizing grade II and *** the cooling rate gradually decreases from surface to the center of the HCCIBs,the number of spheroidized graphite is gradually reduced,the size is gradually increased,the shape factor is decreased,and the pearlite content and lamellate spacing are *** the horizontal direction of the section,the hardness of the material is distributed symmetrically around the center of the *** the vertical direction,the hardness distribution in the center of the HCCDIBs is asymmetrical due to the gravity during the solidification ***,the microstructure in the lower part of the section solidifies relatively *** left-edge has the best tensile mechanical properties,and the ultimate tensile strength,yield tensile strength and elongation are 597.3 MPa,418.5 MPa and 9.6%,*** tensile fracture belongs to the ductile-brittle hybrid *** comprehensive performances of LZQT600-3 HCCDIBs meet the actual application requirements of ultra-high pressure hydraulic plunger pump cylinder.

关键词： horizontal continuous casting(HCC) nodular cast iron ductile iron bars microstructure mechanical properties

Predicting submerged vegetation drag with a machine learning-based method

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Journal of Hydrodynamics 2024年第3期36卷 534-545页

作者： Meng-yang liu Hong-wu Tang Sai-yu yuan Jing Yan College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China Key Laboratory of Hydrologic-Cycle and Hydrodynamic-System of Ministry of Water Resources Hohai UniversityNanjing210098China

Accurate estimation of the drag forces generated by vegetation stems is crucial for the comprehensive assessment of the impact of aquatic vegetation on hydrodynamic processes in aquatic *** coupling relationship between vegetation layer flow velocity and vegetation drag makes precise prediction of submerged vegetation drag forces particularly *** present study utilized published data on submerged vegetation drag force measurements and employed a genetic programming(GP)algorithm,a machine learning technique,to establish the connection between submerged vegetation drag forces and flow and vegetation *** using the bulk velocity,U,as the reference velocity scale to define the drag coefficient,C_(d),and stem Reynolds number,the GP runs revealed that the drag coefficient of submerged vegetation is related to submergence ratio(H^(*)),aspect ratio(d^(*)),blockage ratio(ψ^(*)),and vegetation density(λ).The relation between vegetation stem drag forces and flow velocity is implicitly embedded in the definition of C_(d).Comparisons with experimental drag force measurements indicate that using the bulk velocity as the reference velocity,as opposed to using the vegetation layer average velocity,U_(v),eliminates the need for complex iterative processes to estimate U_(v)and avoids introducing additional errors associated with U_(v)*** approach significantly enhances the model’s predictive capabilities and results in a simpler and more user-friendly formula expression.

关键词： Drag coefficient genetic programming algorithm submerged vegetation flow resistance cylinder array

NCAD v1.0: a database for non-coding variant annotation and interpretation

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Journal of Genetics and Genomics 2024年第2期51卷 230-242页

作者： Xiaoshu Feng Sihan liu Ke Li Fengxiao Bu Huijun yuan Institute of Rare Diseases West China HospitalSichuan UniversityChengduSichuan 610044China

The application of whole genome sequencing is expanding in clinical diagnostics across various genetic disorders, and the significance of non-coding variants in penetrant diseases is increasingly being demonstrated. Therefore, it is urgent to improve the diagnostic yield by exploring the pathogenic mechanisms of variants in non-coding regions. However, the interpretation of non-coding variants remains a significant challenge, due to the complex functional regulatory mechanisms of non-coding regions and the current limitations of available databases and tools. Hence, we develop the non-coding variant annotation database (NCAD, http://***/), encompassing comprehensive insights into 665,679,194 variants, regulatory elements, and element interaction details. Integrating data from 96 sources, spanning both GRCh37 and GRCh38 versions, NCAD v1.0 provides vital information to support the genetic diagnosis of non-coding variants, including allele frequencies of 12 diverse populations, with a particular focus on the population frequency information for 230,235,698 variants in 20,964 Chinese individuals. Moreover, it offers prediction scores for variant functionality, five categories of regulatory elements, and four types of non-coding RNAs. With its rich data and comprehensive coverage, NCAD serves as a valuable platform, empowering researchers and clinicians with profound insights into non-coding regulatory mechanisms while facilitating the interpretation of non-coding variants.

关键词： Non-coding variants Annotation Variant interpretation Database

Stochastic Gradient Compression for Federated Learning over Wireless Network

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China Communications 2024年第4期21卷 230-247页

作者： Lin Xiaohan liu yuan Chen Fangjiong Huang Yang Ge Xiaohu School of Electronic and Information Engineering South China University of TechnologyGuangzhou 510641China Key Laboratory of Dynamic Cognitive System of Electromagnetic Spectrum Space Ministry of Industry and Information TechnologyNanjing University of Aeronautics and AstronauticsNanjing 210016China School of Electronic Information and Communications Huazhong University of Science and TechnologyWuhan 430074China

As a mature distributed machine learning paradigm,federated learning enables wireless edge devices to collaboratively train a shared AI-model by stochastic gradient descent(SGD).However,devices need to upload high-dimensional stochastic gradients to edge server in training,which cause severe communication *** address this problem,we compress the communication by sparsifying and quantizing the stochastic gradients of edge *** first derive a closed form of the communication compression in terms of sparsification and quantization ***,the convergence rate of this communicationcompressed system is analyzed and several insights are ***,we formulate and deal with the quantization resource allocation problem for the goal of minimizing the convergence upper bound,under the constraint of multiple-access channel *** show that the proposed scheme outperforms the benchmarks.

关键词： federated learning gradient compression quantization resource allocation stochastic gradient descent(SGD)

Track-Pattern-Based Characteristics of Extratropical Transitioning Tropical Cyclones in the Western North Pacific

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Advances in Atmospheric Sciences 2024年第6期41卷 1251-1263页

作者： Hong HUANG Dan WU yuan WANG Zhen WANG Yu liu College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410000China No.31631 Army of PLA Huizhou 516000China School of Atmospheric Sciences and Key Laboratory of Mesoscale Severe Weather/Ministry of Education Nanjing 210023China No.93721 Army of PLA Shuozhou 038300China

Based on the Regional Specialized Meteorological Center(RSMC)Tokyo-Typhoon Center best-track data and the NCEP-NCAR reanalysis dataset,extratropical transitioning(ET)tropical cyclones(ETCs)over the western North Pacific(WNP)during 1951–2021 are classified into six clusters using the fuzzy c-means clustering method(FCM)according to their track *** characteristics of the six hard-clustered ETCs with the highest membership coefficient are *** tropical cyclones(TCs)that were assigned to clusters C2,C5,and C6 made landfall over eastern Asian countries,which severely threatened these *** landfalling TCs,93.2%completed their ET after landfall,whereas 39.8%of ETCs completed their transition within one *** frequency of ETCs over the WNP has decreased in the past four decades,wherein cluster C5 demonstrated a significant decrease on both interannual and interdecadal timescales with the expansion and intensification of the western Pacific subtropical high(WPSH).This large-scale circulation pattern is favorable for C2 and causes it to become the dominant track pattern,owning to it containing the largest number of intensifying ETCs among the six clusters,a number that has increased insignificantly over the past four *** surface roughness variation and three-dimensional background circulation led to C5 containing the maximum number of landfalling TCs and a minimum number of intensifying *** results will facilitate a better understanding of the spatiotemporal distributions of ET events and associated environment background fields,which will benefit the effective monitoring of these events over the WNP.

关键词： Western North Pacific tropical cyclone extratropical transition fuzzy c-means clustering method

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Design methodology,synthesis,and control strategy of the high-speed planetary rover

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Frontiers of Mechanical Engineering 2024年第2期19卷 59-74页

作者： Renchao LU Haibo GAO Zhen liu Runze yuan Zongquan DENG State Key Laboratory of Robotics and Systems Harbin Institute of TechnologyHarbin 150001China

The planned missions to explore the surfaces of the Moon and Mars require high exploration efficiency,thus imposing new demands on the mobility system of planetary *** this paper,a design method for a high-speed planetary rover(HPR)is proposed,and the representative configurations are modeled and ***,the influence of the planetary surface environment on the design of HPRs is analyzed,and the design factors for HPRs are determined by studying a single-wheel ***,a design methodology for HPRs is *** adaptive suspension mechanisms of a four-wheeled rover are synthesized using the all-wheel-attachment condition and position and orientation characteristics theory,which are expressed in the form of a graph theory for the increase in elastic components and active ***,a dynamic model is built,and a simulation is carried out for the proposed *** validity of the proposed method and rover is verified,thus highlighting their potential application in future planetary exploration.

关键词： design methodology spectrum analysis high-speed planetary rover type synthesis

Complex transmission matrix retrieval for a highly scattering medium via regional phase differentiation

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Photonics Research 2024年第5期12卷 876-883页

作者： QIAOZHI HE RONGJUN SHAO yuan Qu LINXIAN liu CHUNXU DING JIAMIAO YANG School of Electronic Information and Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China Institute of Marine Equipment Shanghai Jiao Tong UniversityShanghai 200240China School of Automation and Software Engineering Shanxi UniversityTaiyuan 030006China

Accurately measuring the complex transmission matrix(CTM) of the scattering medium(SM) holds critical significance for applications in anti-scattering optical imaging, phototherapy, and optical neural networks. Noninterferometric approaches, utilizing phase retrieval algorithms, can robustly extract the CTM from the speckle patterns formed by multiple probing fields traversing the SM. However, in cases where an amplitude-type spatial light modulator is employed for probing field modulation, the absence of phase control frequently results in the convergence towards a local optimum, undermining the measurement accuracy. Here, we propose a high-accuracy CTM retrieval(CTMR) approach based on regional phase differentiation(RPD). It incorporates a sequence of additional phase masks into the probing fields, imposing a priori constraints on the phase retrieval algorithms. By distinguishing the variance of speckle patterns produced by different phase masks, the RPD-CTMR can effectively direct the algorithm towards a solution that closely approximates the CTM of the SM. We built a prototype of a digital micromirror device modulated RPD-CTMR. By accurately measuring the CTM of diffusers, we achieved an enhancement in the peak-to-background ratio of anti-scattering focusing by a factor of 3.6, alongside a reduction in the bit error rate of anti-scattering image transmission by a factor of 24. Our proposed approach aims to facilitate precise modulation of scattered optical fields, thereby fostering advancements in diverse fields including high-resolution microscopy, biomedical optical imaging, and optical communications.

关键词： matrix phase holds

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Separation density prediction of geldart A^(-)dense medium in gas-solid fluidized bed coal beneficiators

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Particuology 2024年第9期92卷 251-262页

作者： Chenyang Zhou Chengguo liu Yue yuan Zhijie Fu Jesse Zhu Chenlong Duan School of Chemical Engineering and Technology China University of Mining and TechnologyXuzhou221116China Particle Technology Research Centre Western UniversityLondonOntarioN6A 5B9Canada

Gas-solid Fluidized Bed Coal Beneficiator(GFBCB)process is a crucial dry coal beneficiation fluidization *** work employs the GFBCB process alongside a novel Geldart A^(-)dense medium,consisting of Geldart A magnetite particles and Geldart C ultrafine coal,to separate small-size separated objects in the *** effects of various operational conditions,including the volume fraction of ultrafine coal,the gas velocity,the separated objects size,and the separation time,were investigated on the GFBCB's separation *** results indicated that the probable error for 6∼3 mm separated objects could be controlled within 0.10 g/cm^(3).Compared to the traditional Geldart B/D dense medium,the Geldart A/A^(-)dense medium exhibited better size-dependent separation performance with an overall probable error 0.04∼0.12 g/cm^(3).Moreover,it achieved a similar separation accuracy to the Geldart B/D dense medium fluidized bed with different external energy for the small-size object *** work furthermore validated a separation density prediction model based on theoretical derivation,available for both Geldart B/D dense medium and Geldart A/A^(-)dense medium at different operational conditions.

关键词： GFBCB Geldart A^(-)dense medium Separation density Separated objects size Prediction model

Comprehensive analyses of the proteome and ubiquitome revealed mechanism of high temperature accelerating petal abscission in tree peony

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Horticultural Plant Journal 2024年第1期10卷 205-222页

作者： Chunying liu Ziqi liu Yanchao yuan Yuxi Zhang Yifu Fang Junqiang Chen Shupeng Gai Key Laboratory of Plant Biotechnology in Shandong Province College of Life SciencesQingdao Agricultural UniversityQingdaoShandong 266109China Shandong Academy of Forestry JinanShandong 250014China

Tree peony(Paeonia suffruticosa Andrews)is a well-known ornamental plant with high economic value,but the short fluorescence is a key obstacle to its ornamental value and industry *** temperature accelerates flower senescence and abscission,but the associated mechanisms are poorly *** this study,the tandem mass tag(TMT)proteome and label-free quantitative ubiquitome from tree peony cut flowers treated with 20℃for 0 h(RT0),20℃or 28℃for 60 h(RT60 or HT60)were examined based on morphological observation,***,6970 proteins and 1545 lysine ubiquitinated(Kub)sites in 844 proteins were *** residues(such as glutamate and aspartate)neighboring the Kub sites were in preference,and 36.01%of the Kub sites were located on the protein *** differentially expressed proteins(DEPs)and Kub-DEPs in HT60 vs RT60 were mainly enriched in ribosomal protein,protein biosynthesis,secondary metabolites biosynthesis,flavonoid metabolism,carbohydrate catabolism,and auxin biosynthesis and signaling revealed by GO and KEGG analysis,accompanying the increase of endogenous abscisic acid(ABA)accumulation and decrease of endogenous indoleacetic acid(IAA)***,the expression patterns of six enzymes(SAMS,ACO,YUC,CHS,ANS and PFK)putatively with Kub modifications were analyzed by proteome and real-time quantitative *** cell-free degradation assays showed PsSAMS and PsACO proteins could be degraded via the 26 S proteasome system in tree peony ***,a working model was proposed for the acceleration of flower senescence and abscission by high *** summary,all results contributed to understanding the mechanism of flower senescence induced by high temperature and prolonging fluorescence in tree peony.

关键词： Tree peony Proteome Ubiquitome High temperature Flower senescence