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Two-dimensional semiconductor transistors and integrated circuits for advanced technology nodes

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National Science Review 2024年第03期11卷 11-13页

作者： Weisheng Li haoliang Shen hao Qiu Yi shi Xinran Wang National Laboratory of Solid-State Microstructures School of Electronic Science and Engineering and Collaborative Innovation Center of Advanced Microstructures Nanjing University Suzhou Laboratory The Interdisciplinary Research Center for Future Intelligent Chips(Chip-X) Nanjing University School of Integrated Circuits Nanjing University

Two-dimensional(2D) semiconductors,particularly transition metal dichalcogenides, exhibit high mobility within atomic-scale thickness, immunity to short-channel effects, and back-end-of-the-line(BEOL) compatibility wi...

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Span-based joint entity and relation extraction augmented with sequence tagging mechanism

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Science China(Information Sciences) 2024年第5期67卷 84-98页

作者： Bin JI Shasha LI hao XU jie YU Jun MA Huijun LIU Jing YANG College of Computer National University of Defense Technology

Span-based joint extraction simultaneously conducts named entity recognition(NER) and relation extraction(RE) in a text span form. However, since previous span-based models rely on span-level classifications, they cannot benefit from token-level label information, which has been proven advantageous for the task. In this paper, we propose a sequence tagging augmented span-based network(STSN), a spanbased joint model that can make use of token-level label information. In STSN, we construct a core neural architecture by deep stacking multiple attention layers, each of which consists of three basic attention *** the one hand, the core architecture enables our model to learn token-level label information via the sequence tagging mechanism and then uses the information in the span-based joint extraction; on the other hand, it establishes a bi-directional information interaction between NER and RE. Experimental results on three benchmark datasets show that STSN consistently outperforms the strongest baselines in terms of F1,creating new state-of-the-art results.

关键词： joint extraction named entity recognition relation extraction span sequence tagging mechanism

A deoxidation thermodynamic model for 304 stainless steel considering multiple-components coupled reactions

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Journal of Iron and Steel Research International 2024年第1期31卷 74-91页

作者： Yan Yan Guang-hao Shang Li-ping Zhang Shao-ying Li Han-jie Guo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials Beijing100083China Henan Jinhui Stainless Steel Industry Group Co. Ltd.Xuchang461500HenanChina Changge Jinhui Recycling Metal R&D Co. Ltd.Xuchang461500HenanChina

A thermodynamic model for predicting the equilibrium oxygens of 304 stainless steel was developed based on the theory of slag-steel equilibrium,the law of mass conservation,and the ion and molecule coexistence *** the developed model,the Fe-Cr-Mn-Si-Al-S-O-melts reaction system and CaO-MgO-CaF_(2)-FeO-MnO-Al_(2)O_(3)-SiO_(2)-Cr2O_(3)slags were *** oxygen contents calculated by the model are in good agreement with experimental results and reference *** equilibrium oxygen contents in 304 stainless steel mainly decrease with increasing binary basicity(w(CaO)/w(SiO_(2)),where w(i)is the mass percentage of component i)and decreasing *** binary basicity at 2.0 while maintaining temperatures lower than 1823 K will keep the oxygen contents in the 304 stainless steel lower than 15×10^(-6).The equilibrium oxygen contents may also be decreased with increasing content of MgO in slags,which is more significant at lower binary ***,a small amount of FeO,MnO,and Al_(2)O_(3)(about 0-2.5 wt.%)in slags has little effect on equilibrium oxygen ***,it is found that the[C]-[O]reaction may occur during refining process but will not significantly affect the equilibrium oxygen contents.

关键词： Complex deoxidation Thermodynamic model Ion and molecule coexistence theory 304 stainless steel Slag-steel reaction

Effect of different bottom blowing elements on stirring characteristics of molten bath in converter

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Journal of Iron and Steel Research International 2024年第2期31卷 368-376页

作者： Ming Lv Shuang-ping Chen Hong-min Guo Yi-jie hao Xiang-dong Xing School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an710055ShaanxiChina Shaanxi Longmen Steel Company Hancheng715405ShaanxiChina

The bottom blowing element is the key equipment to ensure the bottom blowing effect of the *** types of bottom blowing elements,dispersive type(D1),double circular seam(D2)and straight cylinder type(D3),were built,and the effects of bottom blowing element type on molten bath flow,wall erosion and furnace bottom erosion were *** was found that when the bottom blowing elements of dispersive type(D1)and double circular seam(D2)were used,the dead zone area in the lower part of the molten bath was smaller,and the high-speed zone area was larger;therefore,the stirring effect on the bottom melt was *** the straight cylinder type(D3)bottom blowing element was used,the gas penetrated the molten bath at a faster rate to reach the surface of molten bath and failed to disperse in the bottom molten bath,and the wall shear stress near the nozzle outlet was *** argon was blown by three different bottom blowing elements,the area of the wall shear stress greater than 3 Pa was 4.8,5.6 and 8.7 cm2,respectively,within 0.2 m of the bottom blowing nozzle outlet.

关键词： Converter steelmaking Bottom blowing element Molten bath stirring Wall erosion

Method of improving pedestrian navigation performance based on chest card

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Journal of Systems Engineering and Electronics 2024年第4期35卷 987-998页

作者： CHENG hao GAO Shuang CAI Xiaowen WANG Yuxuan WANG jie School of Instrumentation and Optoelectronic Engineering Beihang UniversityBeijing 100191China School of Automation and Electronic Information Xiangtan UniversityXiangtan 411105China Navigation Guidance and Control Graduate School of the Second Institute of China Aerospace Science and Industry CorporationBeijing 100854China

With the development of positioning technology,loca-tion services are constantly in demand by *** a primary location service pedestrian navigation has two main approaches based on radio and inertial *** pedestrian naviga-tion based on radio is subject to environmental occlusion lead-ing to the degradation of positioning *** pedestrian navigation based on micro-electro-mechanical system inertial measurement unit(MIMU)is less susceptible to environmental interference,but its errors dissipate over *** this paper,a chest card pedestrian navigation improvement method based on complementary correction is proposed in order to suppress the error divergence of inertial navigation *** suppress atti-tude errors,optimal feedback coefficients are established by pedestrian motion *** extend navigation time and improve positioning accuracy,the step length in subsequent movements is compensated by the first step *** experi-mental results show that the positioning accuracy of the pro-posed method is improved by more than 47%and 44%com-pared with the pure inertia-based method combined with step compensation and the traditional complementary filtering com-bined method with step *** proposed method can effectively suppress the error dispersion and improve the positioning accuracy.

关键词： pedestrian navigation micro-electro-mechanical sy-stem(MEMS) inertial navigation complementary filtering

Aboveground biomass stocks of species-rich natural forests in southern China are influenced by stand structural attributes,species richness and precipitation

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Plant Diversity 2024年第4期46卷 530-536页

作者： Wen-hao Zeng shi-Dan Zhu Ying-Hua Luo Wei shi Yong-Qiang Wang Kun-Fang Cao State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources College of ForestryGuangxi UniversityNanning 530004China Guangxi Key Laboratory of Forest Ecology and Conservation College of ForestryGuangxi UniversityNanning 530004China Key Laboratory of National Forestry and Grassland Administration on Biodiversity Conservation in Karst Mountainous Areas of Southwestern China School of Life SciencesGuizhou Normal UniversityHuaxi College TownGui'an DistrictGuiyang 550025China

Forests,the largest terrestrial carbon sinks,play an important role in carbon sequestration and climate change *** forest attributes and environmental factors have been shown to impact aboveground biomass,their influence on biomass stocks in species-rich forests in southern China,a biodiversity hotspot,has rarely been *** this study,we characterized the effects of environmental factors,forest structure,and species diversity on aboveground biomass stocks of 30 plots(1 ha each) in natural forests located within seven nature reserves distributed across subtropical and marginal tropical zones in Guangxi,*** results indicate that forest aboveground biomass stocks in this region are lower than those in mature tropical and subtropical forests in other ***,we found that aboveground biomass was positively correlated with stand age,mean annual precipitation,elevation,structural attributes and species richness,although not with species *** we compared stands with the same basal area,we found that aboveground biomass stock was higher in communities with a higher coefficient of variation of diameter at breast *** findings highlight the importance of maintaining forest structural diversity and species richness to promote aboveground biomass accumulation and reveal the potential impacts of precipitation changes resulting from climate warming on the ecosystem services of subtropical and northern tropical forests in ***,many natural forests in southern China are not fully ***,their continued growth will increase their carbon storage over time.

关键词： Subtropical forest Marginal tropical forest Aboveground biomass Species diversity Forest structural attribute Environment factor

Application of deep learning in iron ore sintering process:a review

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Journal of Iron and Steel Research International 2024年第5期31卷 1033-1049页

作者： Yu-han Gong Chong-hao Wang jie Li Muhammad Nasiruddin Mahyuddin Mohamad Tarmizi Abu Seman School of Electrical and Electronic Engineering Universiti Sains Malaysia14300 Nibong TebalPenangMalaysia College of Electrical Engineering North China University of Science and TechnologyTangshan 063210HebeiChina Technology Transfer Center North China University of Science and TechnologyTangshan 063210HebeiChina School of Metallurgy and Energy North China University of Science and TechnologyTangshan 063210HebeiChina

In the wake of the era of big data,the techniques of deep learning have become an essential research direction in the machine learning field and are beginning to be applied in the steel *** sintering process is an extremely complex industrial *** the main process of the blast furnace ironmaking industry,it has great economic value and environmental protection significance for iron and steel *** is also one of the fields where deep learning is still in the exploration *** order to explore the application prospects of deep learning techniques in iron ore sintering,a comprehensive summary and conclusion of deep learning models for intelligent sintering were presented after reviewing the sintering process and deep learning models in a large number of research ***,the mechanisms and characteristics of parameters in sintering processes were introduced and analysed in detail,and then,the development of iron ore sintering simulation techniques was ***,deep learning techniques were introduced,including commonly used models of deep learning and their ***,the current status of applications of various types of deep learning models in sintering processes was elaborated in detail from the aspects of prediction,controlling,and optimisation of key *** speaking,deep learning models that could be more effectively implemented in more situations of the sintering and even steel industry chain will promote the intelligent development of the metallurgical industry.

关键词： Deep learning Sintering process Modelling Simulation technology Intelligent sintering

Observation of gapless corner modes of photonic crystal slabs in synthetic translation dimensions

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Photonics Research 2024年第3期12卷 444-455页

作者： WEN-JIN ZHANG hao-CHANG MO WEN-jie CHEN XIAO-DONG CHEN JIAN-WEN DONG School of Physics&State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-sen UniversityGuangzhou 510275China

Second-order topological photonic crystals support localized corner modes that deviate from the conventional bulk-edge ***,the frequency shift of corner modes spanning the photonic band gap has not been experimentally ***,we observe the gapless corner modes of photonic crystal slabs within a parameter space by considering translation as an additional synthetic *** corner modes,protected by topological pumping in synthetic translation dimensions,are found to exist independently of the specific corner *** gapless corner modes are experimentally imaged via the near-field scanning measurement and validated numerically by full-wave *** propose a topological rainbow with gradient translation,demonstrating the ability to extract and separate specific frequency components of light into different spatial *** work contributes to the advancement of topological photonics and provides valuable insights into the exploration of gapless corner modes in synthetic dimensions.

关键词： translation dimensions corner

Hyperbranched polymer hollow-fiber-composite membranes for pervaporation separation of aromatic/aliphatic hydrocarbon mixtures

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Chinese Journal of Chemical Engineering 2024年第5期69卷 13-22页

作者： Tong Liu hao Sun Xiangqiong Wang jie Li Zhanquan Zhang Pei Wu Naixin Wang Quanfu An Beijing Key Laboratory for Green Catalysis and Separation Department of Chemical EngineeringCollege of Materials Science and EngineeringBeijing University of TechnologyBeijing 100124China Petrochemical Research Institute CNPCBeijing 102206China

The separation of aromatic/aliphatic hydrocarbon mixtures is crucial in the petrochemical *** is regarded as a promising approach for the separation of aromatic compounds from alkanes. Developing membrane materials with efficient separation performance is still the main task since the membrane should provide chemical stability, high permeation flux, and selectivity. In this study, the hyperbranched polymer(HBP) was deposited on the outer surface of a polyvinylidene fluoride(PVDF)hollow-fiber ultrafiltration membrane by a facile dip-coating method. The dip-coating rate, HBP concentration, and thermal cross-linking temperature were regulated to optimize the membrane *** obtained HBP/PVDF hollow-fiber-composite membrane had a good separation performance for aromatic/aliphatic hydrocarbon mixtures. For the 50%/50%(mass) toluene/n-heptane mixture, the permeation flux of optimized composite membranes could reach 1766 g·m^(-2)·h^(-1), with a separation factor of 4.1 at 60℃. Therefore, the HBP/PVDF hollow-fiber-composite membrane has great application prospects in the pervaporation separation of aromatic/aliphatic hydrocarbon mixtures.

关键词： Aromatic/aliphatic hydrocarbons Hyperbranched polymer Pervaporation Hollow fiber membrane Dip-coating