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Journal of Iron and Steel Research(International) 2023年第1期30卷 64-73页

作者： Chun-feng Bai Bo Wang jie Ma jie-yu Zhang Wan-ping Pan State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai 200072China School of Materials Science and Engineering Shanghai UniversityShanghai 200072China Anhui Jianzhu University Hefei 230601AnhuiChina

In the twin-roll strip casting process,molten steel solidifies by losing heat through its interface with the casting rollers.The heat extraction along this interface has an effect on the quality of the strips and should be affected by coating,rolls’material,and cooling water flow rate.It is necessary to understand the effect of these casting parameters on the solidification structure of twin-roll strip casting.A three-dimensional computational domain is set up to simulate the solidification process of molten steel and heat exchange between steel strip/air,coating,rolls,and cooling water in the channel of roll sleeves.The effect of the cooling water intensity and flow intensity of molten steel in the pool on the solidification structures is studied during the thermal cycle of rolls in the twin-roll strip casting.These predicted results are helpful to optimize casting parameters and improve the strip quality in the twin-roll strip casting process.

关键词： Twin-roll strip casting Solidification structure Numerical simulation Thermal cycle Cellular automata finite element model

Prognostic factors of pacing-induced cardiomyopathy

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Chinese Medical Journal 2020年第13期133卷 1533-1539页

作者： Hong zhang yu-jie Zhou yu-jie Zeng Emergency and Critical Care Center Beijing Anzhen HospitalCapital Medical UniversityBeijing 100029China Department of Cardiology 12th WardBeijing Anzhen HospitalCapital Medical UniversityBeijing Institute of Heart Lung and Blood Vessel DiseaseBeijing Key Laboratory of Precision Medicine of Coronary Atherosclerotic DiseaseClinical Center for Coronary Heart DiseaseCapital Medical UniversityBeijing 100029China

Background:The detrimental outcomes of right ventricular pacing on left ventricular electromechanical function ultimately result in heart failure,a phenomenon termed pacing-induced cardiomyopathy(PICM)in clinical research.This study aimed to validate prognostic factors that can be used to identify patients with higher susceptibility to progress to the stage of cardiomyopathy before pacemaker implantation.Methods:This observational analysis enrolled 256 patients between January 2013 and June 2016,23(8.98%)of whom progressed to PICM after 1 year of follow-up.A Cox proportional hazard model was used to analyze the prognostic factors associated with PICM.Dose-response analysis was used to evaluate the relationship between significant indicators in multifactor analysis and PICM.Results:The mean values of left ventricular ejection fraction before and after pacemaker implantation in 23 patients diagnosed with PICM were 62.3%and 42.7%,respectively.Univariate analysis showed that sex,atrio-ventricular block,paced QRS duration,and ventricular pacing percentage were significantly associated with PICM.In the multivariate analysis,male sex(hazard ratio:1.20,95%confidence interval[CI]:1.09-1.33,P<0.005),paced QRS duration(hazard ratio:1.95 per 1 ms increase,95%CI:1.80-2.12,P<0.001),and ventricular pacing percentage(hazard ratio:1.65 per 1%increase,95%CI:1.51-1.79,P<0.001)were independent prognostic factors associated with the development of PICM.The ventricular pacing percentage and paced QRS duration level defined by the dose-response analysis were positively associated with PICM(P<0.05).Conclusions:Our findings indicated that paced QRS duration and ventricular pacing percentage were the most sensitive prognostic factors for PICM.

关键词： Right ventricular pacing Pacing-induced cardiomyopathy Heart failure

Physical simulation of mixing on a C-H2 smelting reduction reactor with different tracer feeding positions

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Journal of Iron and Steel Research(International) 2020年第9期27卷 1018-1034页

作者： Jin-yin Xie Bo Wang jie-yu Zhang State Key Laboratory of Advanced Special Steel and Shanghai Key Laboratory of Advanced Ferrometallurgy School of Materials Science and EngineeringShanghai UniversityShanghai 200072China

With the growing demand for energy saving,emission reduction,and green metallurgy,we had designed a new C-H2 smelting reduction reactor.In order to solve the key problem that the heat transfer efficiency from high temperature oxidation zone in upper region to low temperature reduction zone in lower region is low in traditional metallurgical reduction reactor,a water simulation was adopted to optimize the mean residence time and to improve the transmission efficiency within the reactor.According to the modified Froude similarity,a water model experimental reactor with a ratio of 1:1 to the prototype was constructed.In the prototype,the feed port was used to feed preheated ore and flux.In order to simulate the effect of different feeding positions of the tracer on the mixing behavior in the molten pool,four points of tracer feeding position were arranged for a systematic study.At the same time,based on double-row side nozzle with thick slag layer in a C-H2 smelting reduction reactor,nine influencing factors,including relative angle between upper and lower side nozzles,were studied.The experimental results showed that the tracer feeding position had a great influence on the mean residence time,and the relative angle also had a great influence on tracer feeding position.Finally,through comprehensive analysis,the optimal condition parameters were obtained under different tracer feeding positions.These results provide valuable help for the design and optimization of the C-H2 smelting reduction reactor.

关键词： Smelting reduction reactor Tracer feeding position Double-row side blowing Mean residence time Relative angle Horizontal angle Vertical angle

RCMR 280k:Refined Corpus for Move Recognition Based on PubMed Abstracts

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Data Intelligence 2023年第3期5卷 511-536页

作者： jie Li Gaihong yu Zhixiong zhang National Science Library Chinese Academy of SciencesBeijing 100190China Department of Library Information and Archives ManagementSchool of Economics and ManagementUniversity of Chinese Academy of SciencesBeijing 100190China Key Laboratory of New Publishing and Knowledge Services for Scholarly Journals Beijing 100190China

Existing datasets for move recognition,such as PubMed 20ok RCT,exhibit several problems that significantly impact recognition performance,especially for Background and Objective labels.In order to improve the move recognition performance,we introduce a method and construct a refined corpus based on PubMed,named RCMR 280k.This corpus comprises approximately 280,000 structured abstracts,totaling 3,386,008 sentences,each sentence is labeled with one of five categories:Background,Objective,Method,Result,or Conclusion.We also construct a subset of RCMR,named RCMR_RCT,corresponding to medical subdomain of RCTs.We conduct comparison experiments using our RCMR,RCMR_RCT with PubMed 380k and PubMed 200k RCT,respectively.The best results,obtained using the MSMBERT model,show that:(1)our RCMR outperforms PubMed 380k by 0.82%,while our RCMR_RCT outperforms PubMed 200k RCT by 9.35%;(2)compared with PubMed 380k,our corpus achieve better improvement on the Results and Conclusions categories,with average F1 performance improves 1%and 0.82%,respectively;(3)compared with PubMed 200k RCT,our corpus significantly improves the performance in the Background and Objective categories,with average F1 scores improves 28.31%and 37.22%,respectively.To the best of our knowledge,our RCMR is among the rarely high-quality,resource-rich refined PubMed corpora available.Our work in this paper has been applied in the SciAlEngine,which is openly accessible for researchers to conduct move recognition task.

关键词： Refined corpus Move recognition Sequential sentence classification Corpus construction Corpus analysis

Structural and Rheological Properties of PP/EPR/PE Alloys

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Chinese Journal of Polymer Science 2023年第2期41卷 240-249页

作者： Jia-Qi zhang Yan-jie zhang Chun-yu zhang Quan Chen State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China University of Science and Technology of China Hefei230026China School of Polymer Science and Engineering Qingdao University of Science&TechnologyQingdao266042China

Linear and non-linear rheological properties were examined for in-reactor alloy samples composed of isotactic polypropylene(iPP),ethylene-propylene rubber(EPR),and polyethylene(PE).The samples were prepared through two-or three-stage sequential polymerization,where iPP,as the majority,was synthesized in the first stage,and either EPR or PE,as the minority,was synthesized in the second or third stage.Above Tm of both PE and iPP,the linear viscoelasticity shows two relaxation processes,where the fast and slow processes are attributable to the relaxation of the iPP component and that of the EPR/PE domains,respectively.Both the damping behavior upon applying the step-strain measurements and the shear-thinning behavior under the shear-rate sweep measurements are strongly related to the different degrees of nonlinearity of the two relaxation processes.

关键词： Polypropylene alloy Structure Nonlinear rheology

New Splitting Algorithms for Multiplicative Noise Removal Based on Aubert-Aujol Model

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Numerical Mathematics(Theory,Methods and Applications) 2022年第2期15卷 415-441页

作者： yu Gan jie zhang Huibin Chang School of Mathematical Sciences Tianjin Normal UniversityTianjinChina Department of Mathematics The University of Hong KongHong KongSARChina

In this paper,we propose new algorithms for multiplicative noise removal based on the Aubert-Aujol(AA)model.By introducing a constraint from the forward model with an auxiliary variable for the noise,the NEMA(short for Noise Estimate based Multiplicative noise removal by alternating direction method of multipliers(ADMM))is firstly given.To further reduce the computational cost,an additional proximal term is considered for the subproblem with regard to the original variable,the NEMA_(f)(short for a variant of NEMA with fully splitting form)is further proposed.We conduct numerous experiments to show the convergence and performance of the proposed algorithms.Namely,the restoration results by the proposed algorithms are better in terms of SNRs for image deblurring than other compared methods including two popular algorithms for AA model and three algorithms of its convex variants.

关键词： Alternating direction method of multipliers image denoising and deblurring multiplicative noise total variation

Pose-free assembly retrieval based on spatial-contact skeleton

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Chinese Journal of Aeronautics 2022年第4期35卷 497-507页

作者： Jianfeng yu Jiazhen PANG jie zhang yuan LI School of Mechanical Engineering Northwestern Polytechnical UniversityXi'an 710072China

In complicated product industry such as aircraft manufacturing, an assembly model contains abundant engineering information for use in design, manufacture, and maintenance. Assembly retrieval can be used to find relevant models for knowledge reuse. However, an assembly with rotatable joints may have many poses, which brings difficulty to assembly retrieval, since there is no pose principle for assembly design. Therefore, focused on rotatable joints in assembly, a skeleton-based descriptor for pose-free assembly retrieval is proposed. The centroid points of part surfaces and contact faces in an assembly are extracted to construct a spatial-contact skeleton. The skeletonbased distance is proposed to measure the distance between two surface points, which is invariant to the rotatable joints. The distribution of skeleton distances between two parts is used to describe the pair. Considering a part paired with all other parts in the assembly, the set of part pairs is used to represent a part, and the modified Hausdorff distance is used to measure the dissimilarity between parts for assembly retrieval. Experiments are conducted to compare the accuracy of the proposed descriptor to holistic and structureless descriptors. The proposed method is shown to retrieve assemblies with similar parts and structures regardless of their rotatable joints.

关键词： Assembly retrieval Computer-aided design(CAD) Rotation connection Similarity measure Spatial-contact skeleton

Viromes in marine ecosystems reveal remarkable invertebrate RNA virus diversity

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Science China(Life Sciences) 2022年第2期65卷 426-437页

作者： yu-Yi zhang Yicong Chen Xiaoman Wei jie Cui CAS Key Laboratory of Molecular Virology&Immunology Institut Pasteur of ShanghaiCenter for Biosafety Mega-ScienceChinese Academy of SciencesShanghai 200031China University of Chinese Academy of Sciences Beijing 100049China Laboatory for Marine Biology and Biotechnology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China

Little is known about ocean viromes and the ecological drivers of the evolution of aquatic RNA viruses.This study employed a meta-transcriptomic approach to characterize the viromes of 58 marine invertebrate species across three seas.This revealed the presence of 315 newly identified RNA viruses in nine viral families or orders(Durnavirales,Totiviridae,Bunyavirales,Han-taviridae,Picornavirales,Flaviviridae,Hepelivirales,Solemoviridae,and Tombusviridae),with most of them being sufficiently divergent to the already documented viruses.Notably,this study revealed three marine invertebrate hantaviruses that are rooted to vertebrate hantaviruses,further supporting that hantaviruses may have a marine origin.We have also found evidence for possible host sharing and switch events during virus evolution.Overall,we have revealed the hidden diversity of marine invertebrate RNA viruses.

关键词： ocean aquatic invertebrate RNA virome evolution host sharing

Preparation of gangue ceramsite by sintering pot test and potential analysis of waste heat recovery from flue gas

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Journal of Iron and Steel Research(International) 2023年第7期30卷 1401-1410页

作者： Yi Huang Xiang-jie Duan yu Li Wei zhang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

Preparation of ceramsite from solid waste based on the sintering process is a new technology and had a high efficiency in improving producing capability, decreasing consumption of liquefied petroleum gas (LPG), and recovering waste heat of flue gas. An experiment sintering gangue ceramsite was conducted in a 25 kg scale sintering pot with a 100 cm height. The combustion characteristics, phase transformation, and the release profile of SO_(2)^(*) (SO and/or SO_(2)) and NO_(x)^(*) (N_(2)O, NO, and/or NO_(2)) of gangue ceramsite during the sintering process were studied by X-ray diffraction analysis, X-ray fluorescence spectrometry, thermogravimetry–differential thermogravimetry–differential scanning calorimetry, and measurement of physical properties of ceramsite and gas components of flue gas. The results showed that the gangue ceramsite had excellent properties, and its compressive strength and water absorption were 8.2–9.6 MPa and 8.9%–9.8%, respectively, far exceeding the requirement of standard (GB/T 17431.1–2010). The ignition temperature of gangue ceramsite was 443 ℃, and the ignition loss was 14.60 mass% at 1000 ℃. Kaolinite and calcite disappeared at 600 and 800 ℃, respectively. Albite disappeared and mullite formed at 1000 ℃. Two peaks of SO_(2)^(*) emissions emerged in the range of 311–346 mg m^(-3) near 500 ℃ of upper layer ceramsite and 420–489 mg m^(-3) near 1000 ℃ of lower layer ceramsite, respectively. NO_(x)^(*) emissions peak emerged in the range of 227–258 mg m^(-3) near 550 ℃ of the upper layer ceramsite, which was related to the oxidation of sulfide and the combustion of LPG. Gangue is a direct heat source for sintering of ceramsite as well. During sintering process, the heat of flue gas above and below 400 ℃ accounts for 55.9% and 30.0% of the all-output heat, respectively, and was potentially used for producing waste-heat steam or electricity as by-products and drying raw materials during its own initial sintering process, which can realize combined mass and heat utilization for the gangue an

关键词： Gangue ceramsite Cogeneration SO_(2)^(*) NO_(x)^(*) Flue gas waste heat

Detecting coherence with respect to general quantum measurements

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Science China(Information Sciences) 2023年第8期66卷 52-60页

作者： yu-Cheng CHEN Jiong CHENG Wen-Zhao zhang Cheng-jie zhang School of Physical Science and Technology Ningbo University State Key Laboratory of Precision Spectroscopy School of Physics and Electronic Science East China Normal University

Quantum coherence is crucial in quantum resource theory. Previous studies have mainly focused on standard coherence based on a complete orthogonal reference. Standard coherence has recently been extended to general positive-operator-valued measure(POVM)-based coherence, including block coherence as a special case. Therefore, it is necessary to construct block and POVM-based coherence witnesses to detect them. In this study, we present witnesses for block and POVM-based coherence and obtain the necessary and sufficient conditions for constructing these witnesses. We also discuss possible realizations of some block and POVM-based coherence witnesses in experiments and present examples of measuring block coherence witnesses based on real experimental data. Furthermore, we present an application of block coherence witnesses in a quantum-parameter estimation task with a degenerate Hamiltonian and estimate the unknown parameter by measuring the block coherence witnesses when the input state is block coherent.Finally, we prove that the quantum Fisher information of any block-incoherent state equals zero, which coincides with the result obtained from measuring block coherence witnesses.

关键词： coherence witness general quantum measurements block coherence POVM-based coherence quantum coherence