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A U-Shaped Network-Based Grid Tagging Model for Chinese Named Entity Recognition
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作者 Yan Xiang Xuedong Zhao +3 位作者 Junjun Guo Zhiliang Shi Enbang Chen Xiaobo Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第6期4149-4167,共19页
Chinese named entity recognition(CNER)has received widespread attention as an important task of Chinese information extraction.Most previous research has focused on individually studying flat CNER,overlapped CNER,or d... Chinese named entity recognition(CNER)has received widespread attention as an important task of Chinese information extraction.Most previous research has focused on individually studying flat CNER,overlapped CNER,or discontinuous CNER.However,a unified CNER is often needed in real-world scenarios.Recent studies have shown that grid tagging-based methods based on character-pair relationship classification hold great potential for achieving unified NER.Nevertheless,how to enrich Chinese character-pair grid representations and capture deeper dependencies between character pairs to improve entity recognition performance remains an unresolved challenge.In this study,we enhance the character-pair grid representation by incorporating both local and global information.Significantly,we introduce a new approach by considering the character-pair grid representation matrix as a specialized image,converting the classification of character-pair relationships into a pixel-level semantic segmentation task.We devise a U-shaped network to extract multi-scale and deeper semantic information from the grid image,allowing for a more comprehensive understanding of associative features between character pairs.This approach leads to improved accuracy in predicting their relationships,ultimately enhancing entity recognition performance.We conducted experiments on two public CNER datasets in the biomedical domain,namely CMeEE-V2 and Diakg.The results demonstrate the effectiveness of our approach,which achieves F1-score improvements of 7.29 percentage points and 1.64 percentage points compared to the current state-of-the-art(SOTA)models,respectively. 展开更多
关键词 Chinese named entity recognition character-pair relation classification grid tagging u-shaped segmentation network
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Effect of mold and core preheating temperature on corrosion resistance of casting Al-12Si alloy U-shaped cooling channel
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作者 Guang-long Li Jie Zhang +3 位作者 Meng-yu Wang Rui-ming Su Yang Cao Ying-dong Qu 《China Foundry》 SCIE CAS CSCD 2023年第3期218-224,共7页
Temperature has an important impact on the corrosion resistance of mold with cooling channels prepared by casting method.The effect of preheating temperature of the mold and the carbon fiber core on the roughness and ... Temperature has an important impact on the corrosion resistance of mold with cooling channels prepared by casting method.The effect of preheating temperature of the mold and the carbon fiber core on the roughness and corrosion resistance of U-shaped cooling channels made of Al-12Si alloy was examined in depth.The experimental results suggest that as the preheating temperature increased from 273 K to 573 K,the roughness of the inner wall of the cooling channel reduced from 96.6μm to 77.0μm.When the preheating temperature continued to increase to 723 K,the roughness increased to 85.3μm.The wetting between the Al melt and the carbon fiber will reduce micro bubbles and waves on the channel wall as the preheating temperature rises,thereby reducing the roughness.However,with the further increase of preheating temperature,it will increase the solidification time of the Al melt.At this time,the carbon fiber and Al melt will take more time to react,which increases the roughness of the channel wall to a certain extent.The results of exfoliation corrosion show that the larger roughness will aggravate exfoliation corrosion.The prolongation of high temperature reaction time between the carbon fiber and the Al melt will lead to the segregation of Si,which is easy to cause intergranular corrosion.Therefore,reasonable preheating temperature has an important impact on the roughness and corrosion resistance of U-shaped cooling channels. 展开更多
关键词 u-shaped cooling channels ROUGHNESS exfoliation corrosion intergranular corrosion
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Production and Characterization of a Composite Based on Plaster and Juncus Maritimus Plant Fibers
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作者 Mina Amazal Soumia Mounir +4 位作者 Asma Souidi Malika Atigui Slimane Oubeddou Youssef Maaloufa Ahmed Aharoune 《Fluid Dynamics & Materials Processing》 EI 2024年第9期2059-2076,共18页
Nowadays,materials with a limited impact on the environment are required in the construction sector.Considering the interesting properties of natural elements such as natural fibers,it seems advantageous to use them t... Nowadays,materials with a limited impact on the environment are required in the construction sector.Considering the interesting properties of natural elements such as natural fibers,it seems advantageous to use them to reinforce materials while protecting the environment and guaranteeing economic gain.Along these lines,this research was devoted to studying the effect of untreated natural fibers extracted from the Juncus maritimus plant(from Southern Morocco)on plaster.First,the effect of the percentage of added fibers on the fluidity of the plaster was evaluated by means of the Marsh’s cone method,that is,by measuring the time taken by a known volume of plaster to flow from a cone through a short tube.Then,the highly porous microstructure of the plaster was observed using a scanning electron microscope(SEM).The diffractogram of Juncus maritimus fibers was built by means of a X-ray diffraction(XRD)method.The values obtained for the wet thermal conductivity of the composites decreased from 0.4853 W/m.K for the reference specimen to 0.4324 W/m K for a fiber volume content of 40%.The densities were calculated to determine the lightness of each composite.The mechanical strengths[flexural and compressive]were evaluated for different percentages of rush fibers.The addition of 20%volume fiber was found to improve the flexural strength to 3.63 MPa compared to the sample without fiber(3.36 MPa),thereby ensuring good toughness of the considered material.Nevertheless,a reduction in compressive strength was observed,due to the poor adhesion between the fibers and the plaster matrix. 展开更多
关键词 Composite material juncus maritimus plant plaster thermophysical properties mechanical properties microstructure
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Investigation of the Fermentation Mode of Rice Husk for the Stabilization of Earth Plaster
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作者 Nafissatou Savadogo Yasmine Binta Traore +2 位作者 Nathael Lankoande Philbert Nshimiyimana Adamah Messan 《Journal of Minerals and Materials Characterization and Engineering》 2024年第1期17-36,共20页
Despite its low resistance to humidity, adobe remains the most widely used material for housing construction, particularly in developing countries. The present study aims to assess different modes of use of fermented ... Despite its low resistance to humidity, adobe remains the most widely used material for housing construction, particularly in developing countries. The present study aims to assess different modes of use of fermented RH and to evaluate their influence on the behavior of raw earth for application in plaster. The influences of two types of RH are evaluated: granular rice husk (RHg) and powdered RH (RHp). The clay mainly consists of clay (40%), silt (22%), and sand (38.4%), with a small proportion of gravel (0.24%). Its liquidity limit is 40% and the plasticity index is 26.5%. The mixtures were designed using earth and each of the two rice husks at the volumetric content of 10%, 15% and 20% of the total volume mixed with water 36.5%, 38.5% and 40.3% and fermented for three weeks. Each fermented mixture was added to the soil to form the paste, and 40 × 40 × 160 mm<sup>3</sup> test speciments were made for characterization. The results generally show an improvement in the physico-mechanical properties and water resistance of the mortars containing fermented RH, with an optimal content between 10% and 15%. The powdered RH improved the performance of the mortar better than granular RH. 展开更多
关键词 Earth plaster Rice Husk CLAY FERMENTATION ADOBE
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Thermal Performance Analysis of Plaster Reinforced with Raffia Vinifera Particles for Use as Insulating Materials in Building
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作者 Etienne Malbila Danielle Manuella Djouego Tagne +3 位作者 Bouto Kossi Imbga Lareba Adelaide Ouedraogo Sié Kam David Yemboini Kader Toguyeni 《Journal of Minerals and Materials Characterization and Engineering》 2024年第2期112-138,共27页
The present study focuses on the formulation of new composite consisting of plaster and raffia vinifera particle (RVP) with the purpose to reducing energy consumption. The aim of this study is to test this new compoun... The present study focuses on the formulation of new composite consisting of plaster and raffia vinifera particle (RVP) with the purpose to reducing energy consumption. The aim of this study is to test this new compound as an insulating eco-material in building in a tropical climate. The composites samples were developed by mixing plaster with raffia vinifera particles (RVP) using three different sizes (1.6 mm, 2.5 mm and 4 mm). The effects of four different RVP incorporations rates (i.e., 0wt%, 5wt%;10wt%;15wt%) on physical, thermal, mechanicals properties of the composites were investigated. In addition, the use of the raffia vinifera particles and plaster based composite material as building envelopes thermal insulation material is studied by the habitable cell thermal behavior instrumentation. The results indicate that the incorporation of raffia vinifera particle leads to improve the new composite physical, mechanical and thermal properties. And the parametric analysis reveals that the sampling rate and the size of raffia vinifera particles are the most decisive factor to impact these properties, and to decreases in the thermal conductivity which leads to an improvement to the thermal resistance and energy savings. The best improvement of plaster composite was obtained at the raffia vinifera particles size between 2.5 and 4.0 mm loading of 5wt% (C95P5R) with a good ratio of thermo-physical-mechanical properties. Additionally, the habitable cell experimental thermal behavior, with the new raffia vinifera particles and plaster-based composite as thermal insulating material for building walls, gives an average damping of 4°C and 5.8°C in the insulated house interior environment respectively for cold and hot cases compared to the outside environment and the uninsulated house interior environment. The current study highlights that this mixture gives the new composite thermal insulation properties applicable in the eco-construction of habitats in tropical environments. 展开更多
关键词 Fibres plaster Thermal Test Mechanical Test Insulating Material Indoor Comfort
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Effect of Head Meridian Massage Combined with Auricular Acupoint Plaster on Patients with Insomnia
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作者 Qin Lu Lanping Yao +2 位作者 Huiqin Jiang Liping Zong Jinhua Huang 《Journal of Clinical and Nursing Research》 2024年第6期305-310,共6页
Objective:To study the effect of head meridian massage combined with auricular acupoint plasters on patients with insomnia.Methods:The sample consisted of 50 cases,and all of them were admitted to Yixing Hospital of T... Objective:To study the effect of head meridian massage combined with auricular acupoint plasters on patients with insomnia.Methods:The sample consisted of 50 cases,and all of them were admitted to Yixing Hospital of Traditional Chinese Medicine from January 2022 to December 2023.The patients were divided into an observation group and a control group,with 25 cases in each group.The observation group was treated with a combination of head meridian massage and auricular acupoint plaster while the control group underwent conventional nursing care.The improvement of sleep quality and nursing effect were used as evaluation criteria to compare the clinical effects of the nursing programs.Results:After nursing intervention,the Pittsburgh sleep quality index(PSQI)score of the observation group,which was 7.17±1.41 points was lower than that of the control group(9.04±1.96 points),(t=3.8724,P<0.05).The total efficacy was 96.00%for the observation group and 76.00%for the control group(2=4.1528,P<0.05).Conclusion:Head meridian massage combined with auricular acupoint can improve the sleep quality of patients with insomnia. 展开更多
关键词 Head massage Auricular acupoint plaster INSOMNIA
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Yinqiao Sanhuang Paste Combined with Traditional Chinese Medicine Plaster for the Intervention of Drug Rash Induced by Targeted Therapy in Lung Cancer
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作者 Ya Zhang Jianye Yang 《Proceedings of Anticancer Research》 2024年第4期54-59,共6页
Objective:To observe the efficacy and safety of Yinqiao Sanhuang Paste combined with traditional Chinese medicine plaster in treating drug rash caused by targeted therapy in lung cancer.Methods:A total of 100 lung can... Objective:To observe the efficacy and safety of Yinqiao Sanhuang Paste combined with traditional Chinese medicine plaster in treating drug rash caused by targeted therapy in lung cancer.Methods:A total of 100 lung cancer patients treated at our hospital from January 2021 to December 2023 were selected and randomly divided into an observation group and a control group,with 50 patients in each group.The control group received conventional medication,while the observation group was treated with Yinqiao Sanhuang Paste combined with traditional Chinese medicine plaster.The clinical symptom improvement and adverse reactions in both groups were observed.Results:The effective rate in the control group was 80.00%,while in the observation group,it was 96.00%,with a statistically significant difference between the two groups(P<0.05).The onset time,duration,and significant effect time in the control group were(2.41±0.29)days,(4.42±1.21)days,and(5.45±0.29)days,respectively;in the observation group,they were(2.44±0.21)days,(4.28±1.11)days,and(5.57±1.01)days,respectively.There was no statistically significant difference in the total onset time and total duration between the two groups(P>0.05).The incidence of adverse reactions in the control group was 28.00%,higher than the observation group’s 10.00%(P<0.05).Conclusion:Yinqiao Sanhuang Paste combined with traditional Chinese medicine plaster can effectively reduce the symptoms of drug rash induced by targeted therapy in lung cancer and lower the incidence of adverse reactions,indicating good clinical application value. 展开更多
关键词 Yinqiao Sanhuang Paste Traditional Chinese medicine plaster Drug rash EFFICACY
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Lumbopelvic Fixation and Sacral Decompression for U-shaped Sacral Fractures: Surgical Management and Early Outcome 被引量:9
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作者 Yuan-long XIE Lin CAI +4 位作者 An-song PING Jun LEI Zhou-ming DENG Chao HU Xiao-bing ZHU 《Current Medical Science》 SCIE CAS 2018年第4期684-690,共7页
U-shaped sacral fractures are rare and often difficult to diagnose primarily due to the difficulty in obtaining adequate imaging and the severe associated injuries. These fractures are highly unstable and frequently c... U-shaped sacral fractures are rare and often difficult to diagnose primarily due to the difficulty in obtaining adequate imaging and the severe associated injuries. These fractures are highly unstable and frequently cause neurological deficits. The majority of surgeons have limited experience in management of U-shaped sacral fractures. No standard treatment protocol for U-shaped sacral fractures has been available till now. This study aimed to examine the management of U-shaped sacral fractures and the early outcomes. Clinical data of 15 consecutive patients with U-shaped sacral fracture who were admitted to our trauma center between 2009 and 2014 were retrospectively analyzed. Demographics, fracture classification, mechanism of injury and operative treatment and deformity angle were assessed. All the patients were treated with lumbopelvic fixation or (and) sacral decompression. EQ-5d score was applied to evaluate the patients' quality of life. Of the 15 consecutive patients with U-shaped sacral fracture, the mean age was 28.8 years (range: 15-55 years) at the time of injury. There were 6 females and 9 males. The mean follow- up time was 22.7 months (range: 9-47 months) and mean full weight-bearing time was 9.9 weeks (range: 8-14 weeks). Ten patients received lumbopelvic fixation and sacral decompression, one lombosacral fixation, and 4 merely sacral decompression due to delayed diagnosis or surgery. The post-operation deformity angle (mean 27.87°, and range: 8°-90°) of the sacrum was smaller than that pre-operation (mean 35.67; range: 15-90) with no significance difference noted. At the latest follow-up, all patients obtained neurological recovery with different extents. Visual analogue score (VAS) was reduced from preoperative 7.07 (range: 5-9) to postoperetive 1.93 (range: 1-3). All patients could walk without any aid after treatment. Eight patients were able to care for themselves and undertook some daily activities. Five patients had returned to work full time. In conclusion, lumbopelvic fixation is an effective method for stabilization of U-shaped sacral fractures with fewer complications developed. Effective reduction and firm fixation are the prerequisite of early mobilization and neurological recovery. Sacral decompression effectively promotes neurological recovery even in patients with old U-shaped sacral fractures. 展开更多
关键词 lumbopelvic fixation sacral decompression u-shaped sacral fractures neurological deficit surgical management
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Electrokinetic flow in the U-shaped micro-nanochannels 被引量:3
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作者 Bilong Qiu Lingyan Gong +1 位作者 Zirui Li Jongyoon Han 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2019年第1期36-42,I0005,共8页
U-shaped micro-nanochannels can generate significant flow disturbance as well as locally amplified electric field, which gives itself potential to be microfluidic mixers, electrokinetic pumps,and even cell lysis proce... U-shaped micro-nanochannels can generate significant flow disturbance as well as locally amplified electric field, which gives itself potential to be microfluidic mixers, electrokinetic pumps,and even cell lysis process. Numerical simulation is utilized in this work to study the hidden characteristics of the U-shaped micro-nanochannel system, and the effects of key controlling parameters(the external voltage and pressure) on the device output metrics(current, maximum values of electric field, shear stress and flow velocity) were evaluated. A large portion of current flowing through the whole system goes through the nanochannels, rather than the middle part of the microchannel, with its value increasing linearly with the increase of voltage. Due to the local ion depletion near micro-nanofluidic junction, significantly enhanced electric field(as much as 15 fold at V=1 V and P_0=0) as well as strong shear stress(leading to electrokinetic flow) is generated.With increasing external pressure, both electric field and shear stress can be increased initially(due to shortening of depletion region length), but are suppressed eventually at higher pressure due to the destruction of ion depletion layer. Insights gained from this study could be useful for designing nonlinear electrokinetic pumps and other systems. 展开更多
关键词 u-shaped micro-nanochannels ELECTROKINETIC flow MAXIMUM SHEAR stress U
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GENERAL SOLUTION FOR U-SHAPED BELLOWS OVERALL-BENDING PROBLEMS 被引量:4
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作者 朱卫平 郭平 黄黔 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第4期371-382,共12页
The formulae for stresses and angular displacements of U-shaped bellows overall bending in a meridian plane under pure bending moments are presented based on the general solution for slender ring shells proposed by Zh... The formulae for stresses and angular displacements of U-shaped bellows overall bending in a meridian plane under pure bending moments are presented based on the general solution for slender ring shells proposed by Zhu Weiping, et al. and the solution for ring plates. The results evaluated in this paper are compared with those on EJMA (standards of the expansion joint manufacturers association) and of the experiment given by Li Tingxilz, et al. 展开更多
关键词 flexible shells shells of revolution circular ring shells BELLOWS u-shaped bellows
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Mechanical property of U-Shaped 65Mn steel bumpers for seismic base isolation 被引量:2
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作者 Han Miao Wang Yuandong +1 位作者 Du Hongkai Cui Xiangdong 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2021年第3期791-802,共12页
This study proposes a novel U-shaped 65Mn steel bumper as the displacement restraining device for base-isolated structures with laminated elastomeric rubber bearings.A series of bumpers with different geometric parame... This study proposes a novel U-shaped 65Mn steel bumper as the displacement restraining device for base-isolated structures with laminated elastomeric rubber bearings.A series of bumpers with different geometric parameters were designed and tested under monotonic and cyclic quasi-static loading protocols.The experimental results from a total of 232 specimens were analyzed to develop an analytical model to calculate the backbone curve and the maximum elastic restoring force for U-shaped 65Mn bumpers.Thus,the analytical equations to calculate the elastic,hardening,and unloading stiffness of U-shaped 65Mn bumpers,as well as their maximum elastic restoring force,are validated by using an additional ten groups of bumpers with varying radiuses.These analytical equations can accurately predict the mechanical parameters of U-shaped 65Mn steel bumpers for a design purpose. 展开更多
关键词 u-shaped bumper base isolation EXPERIMENTAL mechanical properties analytical model
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PROBLEMS OF U-SHAPED BELLOWS WITH NONLINEAR DEFORM TION OF LARGE AXISYMMETRICAL DEFLECTION(Ⅰ)—COUNTING NONLINEAR DEFORMATIONS OF RING SHELLS AND COMPRESSED ANGLE OF BELLOWS 被引量:1
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作者 胡俍 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1993年第3期253-267,共15页
This paper follows the work of [1,2]. There are some progress in dealing with moderately small rotations (the squares of rotation angles are the order of magnitude of strains) of middle surface normals of inside and o... This paper follows the work of [1,2]. There are some progress in dealing with moderately small rotations (the squares of rotation angles are the order of magnitude of strains) of middle surface normals of inside and outside ring shells and compressed angle of bellows. Calculation results agree with experiments well. To bellow design, the method given in this paper is of practical value and the discussion of the influence of compressed angle on characteristic relation is helpful. 展开更多
关键词 u-shaped bellows large axisymmetrical deflection compressed angle
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ON PROBLEMS OF U-SHAPED BELLOWS WITH NONLINEAR DEFORMATION OF LARGE AXISYMMETRICAL DEFLECTION(Ⅱ)——COUNTING VARIATION OF THICKNESS DISTRIBUTION 被引量:1
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作者 胡俍 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1993年第6期559-564,共6页
On the basis of paper [1], assuming the logarithm of thickness at arbitrary point on a U-shaped bellows meridian is linear with the logarithm of distance between that point and axis of symmetry, perturbation solutions... On the basis of paper [1], assuming the logarithm of thickness at arbitrary point on a U-shaped bellows meridian is linear with the logarithm of distance between that point and axis of symmetry, perturbation solutions of the corresponding problems of large axisymmetrical deflection are given. The effects of thickness distribution variation, which result from technology factors, on stiffness of bellows are discussed. 展开更多
关键词 u-shaped bellows variation of thickness distribution decay rate
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An ultra-low specific on-resistance trench LDMOS with a U-shaped gate and accumulation layer
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作者 李鹏程 罗小蓉 +4 位作者 罗尹春 周坤 石先龙 张彦辉 吕孟山 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第4期399-404,共6页
An ultra-low specific on-resistance (Ron,sp) oxide trench-type silicon-on-insulator (SOI) lateral double-diffusion metal-oxide semiconductor (LDMOS) with an enhanced breakdown voltage (BV) is proposed and inve... An ultra-low specific on-resistance (Ron,sp) oxide trench-type silicon-on-insulator (SOI) lateral double-diffusion metal-oxide semiconductor (LDMOS) with an enhanced breakdown voltage (BV) is proposed and investigated by simulation. There are two key features in the proposed device: one is a U-shaped gate around the oxide trench, which extends from source to drain (UG LDMOS); the other is an N pillar and P pillar located in the trench sidewall. In the on-state, electrons accumulate along the U-shaped gate, providing a continuous low resistance current path from source to drain. The Ron,sp is thus greatly reduced and almost independent of the drift region doping concentration. In the off-state, the N and P pillars not only enhance the electric field (E-field) strength of the trench oxide, but also improve the E-field distribution in the drift region, leading to a significant improvement in the BV. The BV of 662 V and Ron,sp of 12.4 mΩ.cm2 are achieved for the proposed UG LDMOS. The BV is increased by 88.6% and the Ron,sp is reduced by 96.4%, compared with those of the conventional trench LDMOS (CT LDMOS), realizing the state-of-the-art trade-off between BV and Ron,sp. 展开更多
关键词 TRENCH u-shaped gate specific on-resistance breakdown voltage
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pH-dependent Synthesis of Octa-nuclear Uranyl-oxalate Network Mediated by U-shaped Linkers
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作者 WU Si MEI Lei +3 位作者 HU Kong-Qiu CHAI Zhi-Fang NIE Chang-Ming SHI Wei-Qun 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2020年第2期243-249,I0009-I0014,共13页
In this work,we report a novel octa-nuclear uranyl(U8)motif[(UO2)8O4(μ3-OH)2(μ2-OH)2]4+embedded in a uranyl-oxalate coordination polymer(compound 1)based on a U-shaped linker with extra-long xylylene chains for stab... In this work,we report a novel octa-nuclear uranyl(U8)motif[(UO2)8O4(μ3-OH)2(μ2-OH)2]4+embedded in a uranyl-oxalate coordination polymer(compound 1)based on a U-shaped linker with extra-long xylylene chains for stabilizing the resulting high-nuclear motif through additional cross-linking connectivity.A comparison with dimeric and monomeric uranyl compounds obtained at different pH value from the same hydrothermal system reveals that,solution pH plays a vital role in formation of this octa-nuclear uranyl motif by promoting hydrolysis of uranyl source.Since high similarity of eight uranium centers in this nearly planar U8 motif here,overlapping and broadening of signals in fluorescence,infra-red(IR)and Raman spectra can be found. 展开更多
关键词 actinide coordination polymers octa-nuclear uranyl u-shaped Linker pH effect
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Numerical Simulation of U-Shaped Metal Rings in a Wind-Sand Environment
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作者 Songchen Wang Xinmei Li +2 位作者 Cheng Chai Gen Wang Caibin Lu 《Fluid Dynamics & Materials Processing》 EI 2021年第3期653-666,共14页
The interaction of U-shaped rings used for power transmission hardware with a wind-sand field is simulated numerically.A standard kturbulence model is used in synergy with an Eulerian-Lagrangian approach.The results... The interaction of U-shaped rings used for power transmission hardware with a wind-sand field is simulated numerically.A standard kturbulence model is used in synergy with an Eulerian-Lagrangian approach.The results show that the wind pressure on the windward side of the U-shaped ring is the highest,a negative pressure zone appears on both sides of the U-shaped ring,while a Kármán Vortex Street is created on its leeward side.There are three possible regimes of motion for the sand grains in the wind field.Sand grains with size below 0.125 mm can follow the airflow directly into the contact area of two U-shaped rings.When the sand size is about 0.1 mm,the number of sand grains that are blown into the contact area attains a maximum.Through the simulation of U-shaped rings in the wind-sand field,the dynamics of such processes are explained in detail,thereby providing relevant information for the subsequent protection and design of connecting hardware used for power transmission. 展开更多
关键词 Wind-sand environment connecting hardware u-shaped ring numerical simulation
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Ultralow Specific on-Resistance Trench MOSFET with a U-Shaped Extended Gate
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作者 王卓 李鹏程 +3 位作者 张波 范远航 徐青 罗小蓉 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第6期188-191,共4页
An ultralow specific on-resistance (Ron,sp) trench metal-oxide-semiconductor field effect transistor (MOSFET) with an improved off-state breakdown voltage (BV) is proposed. It features a U-shaped gate around the... An ultralow specific on-resistance (Ron,sp) trench metal-oxide-semiconductor field effect transistor (MOSFET) with an improved off-state breakdown voltage (BV) is proposed. It features a U-shaped gate around the drift region and an oxide trench inserted in the drift region (UG MOSFET). In the on-state, the U-shaped gate induces a high density electron accumulation layer along its sidewall, which provides a low-resistance current path from the source to the drain, realizing an ultralow Ron,sp. The value of Ron,sp is almost independent of the drift doping concentration, and thus the UG MOSFET breaks through the contradiction relationship between R p and the off-state BV. Moreover, the oxide trench folds the drift region, enabling the UG MOSFET to support a high BV with a shortened cell pitch. The UG MOSFET achieves an Ron,sp of 2 mΩ·cm^2 and an improved BV of 216 V, superior to the best existing state-of-the-art transistors at the same BV level 展开更多
关键词 MOSFET UG Ultralow Specific on-Resistance Trench MOSFET with a u-shaped Extended Gate RESURF
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Discussion on Standardization and Automatic Flow Measurement of U-shaped Channel Water
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作者 Xiangkun Liu 《Journal of Electronic Research and Application》 2018年第6期5-9,共5页
In human life,water resources are inseparable.In recent years,China’s population growth has accelerated,and the industrial level has been continuously improved,resulting in the rapid use and waste of water resources.... In human life,water resources are inseparable.In recent years,China’s population growth has accelerated,and the industrial level has been continuously improved,resulting in the rapid use and waste of water resources.The protection and rational distribution of water resources are the most pressing issue in China’s water resources.At present,the water measuring facilities of the U-shaped channel mainly include a straight wall measuring pool,a parabolic throat measuring pool,and a long throat measuring pool.In view of the problems in irrigation measurement,the empirical water measurement of basic open-channel and automatic flow measurement system in irrigation district is summarized to improve the accuracy,fairness,and rationality of water measurement,and promote irrigation district management to a higher level. 展开更多
关键词 u-shaped CHANNEL WATER STANDARDIZATION AUTOMATED flow measurement
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Double U-Shaped Slots Loaded Stacked Patch Antenna for Multiband Operation
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作者 Nagendra Prasad Yadav 《Open Journal of Antennas and Propagation》 2015年第2期9-17,共9页
The design of a seven-band stacked patch antenna for the C, X and Ku band is presented. The antenna consists of an H-slot loaded fed patch, stacked with dual U-slot loaded rectangular patch to generate the seven frequ... The design of a seven-band stacked patch antenna for the C, X and Ku band is presented. The antenna consists of an H-slot loaded fed patch, stacked with dual U-slot loaded rectangular patch to generate the seven frequency bands. The total size of the antenna is 39.25 × 29.25 mm2. The multiband stacked patch antenna is studied and designed using IE3D simulator. For verification of simulation results, the antenna is analyzed by circuit theory concept. The simulated return loss, radiation pattern and gain are presented. Simulated results show that the antenna can be designed to cover the frequency bands from (4.24 GHz to 4.50 GHz, 5.02 GHz to 5.25 GHz) in C-band application, (7.84 GHz to 8.23 GHz) in X-band and (12.16 GHz to 12.35 GHz, 14.25 GHz to 14.76 GHz, 15.25 GHz to 15.51 GHz, 17.52 GHz to 17.86 GHz) in Ku band applications. The bandwidths of each band of the proposed antenna are 5.9%, 4.5%, 4.83%, 2.36%, 3.53%, 1.68% and 1.91%. Similarly the gains of the proposed band are 2.80 dBi, 4.39 dBi, 4.54 dBi, 10.26 dBi, 8.36 dBi and 9.91 dBi, respectively. 展开更多
关键词 H-SHAPE Fed PATCH Microstrip PATCH ANTENNA DOUBLE u-shape Slot Loaded Stacked PATCH Multiband ANTENNA
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Clinical Study on Treatment of Chronic Prostatitis with Lingze Tablets Combined with TCM Herbal Acupoint Plasters
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作者 Hongfei Tian Chuanjing You 《Journal of Clinical and Nursing Research》 2023年第5期180-185,共6页
Objective:To study the therapeutic effect of Lingze tablets combined with traditional Chinese medicine herbal acupoint plasters on chronic prostatitis.Methods:A total of 64 patients with chronic prostatitis who were a... Objective:To study the therapeutic effect of Lingze tablets combined with traditional Chinese medicine herbal acupoint plasters on chronic prostatitis.Methods:A total of 64 patients with chronic prostatitis who were admitted to the Andrology Clinic of Shuyang County Hospital of Traditional Chinese Medicine from March 2021 to March 2023 were randomly divided into a treatment group and a control group,with 32 cases in each group.The control group took Lingze tablets orally,4 tablets/time,3 times/d;the treatment group took the same medication along with traditional Chinese medicine acupoint herbal plasters.The two groups of patients were treated continuously for 6 weeks,and the differences in the relevant indexes of the curative effect were observed.Results:The NIH-Chronic Prostatitis Symptom Index(NIH-CPSI)scores of the two groups significantly reduced after treatment(P<0.05),and the scores of the patients in the treatment group were lower than those in the control group(P<0.05).The treatment received in the treatment group achieved and efficacy of 96.88%,which was significantly higher than that of the group,which was 81.25%(P<0.05).The maximum flow rate(MFR),average flow rate AFR,and urine output of the patients of both groups improved significantly after treatment(P<0.05).However,the experimental group showed better improvements in these indicators(P<0.05).Conclusion:Lingze tablets combined with traditional Chinese medicine acupoint herbal plasters can significantly improve the symptoms and urodynamic function of patients with chronic prostatitis. 展开更多
关键词 Chronic prostatitis Lingze tablet Traditional Chinese medicine Acupoint herbal plasters
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