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International Journal of Oral Science 2013年第3期5卷 167-171页

作者： qian-qian hou Yi-Ming Gao Lei Sun School of Medicine Shanghai Jiao Tong University Department of Stomatology Ruijin Hospital School of Medicine Shanghai Jiao Tong University

This study aimed to evaluate the influence of quartz fiber post placement on the fracture resistance of endodontically treated premolars with different dental defects under dynamic *** extracted single-rooted mandibular premolars were randomized into five *** group was prepared according to numbers of residual walls ranged from 0 to *** each group was divided into two subgroups with one restored with quartz fiber posts and the other without *** no-post groups,gutta percha point 2 mm below cemento-enamel junction was *** resin was adapted to the well and used to shape the core *** tooth was restored with a complete metal *** loading was carried out in a masticatory simulator with a nominal load of 50 N at 2 Hz for 300 000 loading *** a quasi-statically load was applied in a universal testing machine 306 to the long axis with a crosshead speed of 1 mm？min21until *** were analyzed with one-way analysis of variance and pairwise comparison（P,0.05）.No specimens failed during dynamic *** fracture resistance enhanced with the increase of numbers of coronal walls and the differences were significant（P,0.05）.Placement of fiber posts had a significant effect when fewer than two walls remained（P,0.05）,but it had no significant influence in groups with two,three or four walls（P.0.05）.Fiber post did not change failure mode,and the fracture pattern was mainly *** dentin walls need to be retained in *** no less than two walls remained,a fiber post is not always necessary.

关键词： dynamic loading fiber post fracture resistance residual wall

Tailoring conductive network Zn@NPC@MWCNTs nanocomposites derived from ZIF-8 as high-performance electromagnetic absorber for the whole X-Band

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Defence Technology（防务技术） 2023年第5期23卷 189-200页

作者： Shi-bin Lu Ying Meng Hai-bo Wang Xian-wei Jiang Jin Yang Ning Wei Lin Jin Li-juan Wan Hao Tang qian-qian hou Anhui Province Key Laboratory of Simulation and Design for Electronic Information System Hefei Normal UniversityHefei230601PR China Universities Joint Key Laboratory of Photoelectric Detection Science and Technology in Anhui Province Hefei Normal UniversityHefei230601PR China

A porous 3D cross-linked conductive network pierced by multi-wall carbon nanotubes(MWCNTs) was successfully designed from zeolitic imidazolate framework-8(ZIF-8). Zn@NPC@MWCNTs composites were tailored by the facile regulating the mass ratios and thermal annealing treatment. Due to the combination of less eddy current loss and dielectric loss together with multiple reflection attenuation caused by a unique structure. With a 10 wt% filler loading, the Zn@NPC@MWCNTs composites carbonized at 800℃ show two high reflection loss(RL) values with different thicknesses. An RL value is-53.18 dB with 4.09 mm thickness in the C-Band(4-8 GHz), and a minimum RL can reach-74.83 d B(10.8 GHz)with a matching thickness of 2.749 mm. The effective absorption bandwidth is 4 GHz(from 8 to 12 GHz,RL ≤-10 d B), which just covers the full X-band. Low cost and easy preparation can also provide advantages to develop MOF-based materials as effective EMW absorbents.

关键词： ZIF-8 Electromagnetic wave absorption X-band C-Band

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基于声场图像分析的印刷机轴承故障诊断方法

包装工程 2018年第9期39卷 151-157页

作者：邓瑞徐卓飞徐倩倩侯和平张海燕西安理工大学西安710048

目的针对印刷机墨辊轴承的故障信息获取及诊断难等问题,提出一种基于声场图像分析的故障诊断与定位方法。方法首先,构建声音测试系统并划分检测对象的空间区域,逐一采集信号并依据对应空间位置关系进行重构与组合;其次,将一段时间内的... 详细信息

目的针对印刷机墨辊轴承的故障信息获取及诊断难等问题,提出一种基于声场图像分析的故障诊断与定位方法。方法首先,构建声音测试系统并划分检测对象的空间区域,逐一采集信号并依据对应空间位置关系进行重构与组合;其次,将一段时间内的信号能量进行叠加,同时依据空间位置关系形成叠加状态的声场图像信息;然后,引入二维经验模式分解(BEMD)分析空间域图像信息,消除环境噪声干扰并得到声场图像的高频信息。结果对不同位置、不同种类的墨路系统故障轴承进行特征分析与比对,利用IBIMF分量及统计特征实现了轴承内、外圈故障的诊断,利用无量纲特征实现了不同故障位置的有效定位,并通过实验验证了方法的有效性。结论所提出故障诊断方法发挥了非接触测量优势,同时具有较强故障表征能力,适用于同类复杂机械系统。

关键词：声场二维经验模式分解故障诊断印刷机.

Molecular Mechanism of Rice Necrotic Lesion for Optimized Yield and Disease Resistance

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Rice science 2024年第3期31卷 285-299页

作者： hou Xinyue WANG Yuping qian qian REN Deyong State Key Laboratory of Rice Biology and Breeding China National Rice Research InstituteHangzhou 310006China State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China Rice Research InstituteSichuan Agricultural UniversityChengdu 611130China

How to balance rice resistance and yield is an important issue in rice *** with mutated necrotic lesion genes often have persistent broad-spectrum resistance,but this broad-spectrum resistance usually comes at the expense of ***,many necrotic lesion mutants in rice have been identified,and these genes are involved in disease resistance *** review provides a detailed introduction to the characteristics,classification,and molecular mechanisms of necrotic lesion ***,we review the molecular regulatory pathways of genes involved in rice disease ***,we summarize the relationship between resistance and yield in rice using newly developed gene editing *** discuss a rational and precise breeding strategy to better utilize molecular design technology for breeding disease-resistant and high-yield rice varieties.

关键词： rice necrotic lesion regulation mechanism high yield high resistance

Design and simulation of fault diagnosis based on NUIO/LMI for satellite attitude control systems

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Journal of Systems Engineering and Electronics 2012年第4期23卷 581-587页

作者： Yuehua Cheng qian hou Bin Jiang College of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 R R. China Academy of Frontier Science Nanjing University of Aeronautics and Astronautics Nanjing 210016 P. R. China

This paper presents a scheme of fault diagnosis for flexible satellites during orbit maneuver. The main contribution of the paper is related to the design of the nonlinear input observer which can avoid false alarm arising from the disturbance from orbit control force. The effects of orbit control force on the fault diagnosis system for satellite attitude control systems, including the disturbing torque caused by the misalignments and the model uncertainty caused by the fuel consumed, are discussed, where standard Lu- enberger observer cannot work well. Then the nonlinear unknown input observer is proposed to decouple faults from disturbance, Besides, a linear matrix inequality approach is adopted to reduce the effect of nonlinear part and model uncertainties on the observer. The numerical and semi-physical simulation demonstrates the effectiveness of the proposed observer for the fault diagnosis system of the satellite during orbit maneuver.

关键词： orbit control flexible satellite attitude control system,nonlinear unknown input observer (NUIO) fault diagnosis.

Prenatal ultrasonographic findings in Klippel-Trenaunay syndrome:A case report

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World Journal of Clinical Cases 2021年第35期9卷 10994-10998页

作者： hou-Qing Pang qian-qian Gao Department of Ultrasound West China Second University HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Key Laboratory of Obstetric&Gynecological and Pediatric Diseases and Birth Defects of Ministry of Education Sichuan UniversityChengdu 610041Sichuan ProvinceChina

BACKGROUND Klippel-Trenaunay syndrome(KTS)is a rare congenital disorder.A detailed prenatal ultrasound examination plays an important role in the diagnosis of KTS and the subsequent counseling and follow-up of the *** SUMMARY A 25-year-old woman attended our department for a regular *** whole of the right lower extremity and right buttock were observed to be markedly thicker compared to the left one at 18 wk of ***,the lengths of the right femur,tibia and fibula were in the normal *** marked edema and fluid/cystic spaces were detected in the lower *** were no other organ *** vasculature in the right limb was visibly dilated,with much higher intensive blood flow *** congenital embryonic veins were visible in both *** right lower limb exhibited much more hypertrophy compared to the left limb two weeks *** and genetic tests showed normal results with 46 *** the normal karyotype,the family opted to terminate the *** post-mortem examination confirmed asymmetric hypertrophy of the right limb in the fetus and revealed a large area of marked dark-purple superficial capillary malformations occupying the skin of the right lower *** enlargement of veins and soft tissue hypertrophy were also seen on postnatal X-ray and Magnetic Resonance *** revealed severe congestion in the right lower limb.A final diagnosis of KTS was *** KTS may be diagnosed prenatally based on the typical features observed during ultrasound examination.

关键词： Klippel-Trenaunay syndrome Prenatal diagnosis Ultrasonography Case report

Contact Mechanism of Rail Grinding with Open-Structured Abrasive Belt Based on Pressure Grinding Plate

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Chinese Journal of Mechanical Engineering 2023年第2期36卷 341-351页

作者： Zhiwei Wu Wengang Fan Chang qian Guangyou hou School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Key Laboratory of Vehicle Advanced Manufacturing Measuring and Control TechnologyMinistry of EducationBeijing 100044China Railway Engineering Research Institute China Academy of Railway SciencesBeijing 100081China

The current research of abrasive belt grinding rail mainly focuses on the contact mechanism and structural *** with the closed structure abrasive belt grinding,open-structured abrasive belt grinding has excellent performance in dynamic stability,consistency of grinding quality,extension of grinding mileage and improvement of working ***,in the contact structure design,the open-structured abrasive belt grinding rail using a profiling pressure grinding plate and the closed structure abrasive belt using the contact wheel are different,and the contact mechanisms of the two are *** this paper,based on the conformal contact and Hertz theory,the contact mechanism of the pressure grinding plate,abrasive belt and rail is *** finite element simulation and static pressure experiment,the contact behavior of pressure grinding plate,abrasive belt and rail under single concentrated force,uniform force and multiple concentrated force was studied,and the distribution characteristics of contact stress on rail surface were *** results show that under the same external load,there are three contact areas under the three loading *** outer contour of the middle contact area is rectangular,and the inner contour is *** the contact area at both ends,the stress is extremely small under a single concentrated force,the internal stress is drop-shaped under a uniform force,and the internal stress under multiple concentration forces is *** with the three,the maximum stress is the smallest and the stress distribution is more uniform under multiple concentrated ***,the multiple concentrated forces is the best grinding pressure loading *** research provides support for the application of rail grinding with open-structured abrasive belt based on pressure grinding plate,such as contact mechanism and grinding pressure mode selection.

关键词： Rail grinding Abrasive belt Pressure grinding plate Contact stress

Facile solution-processed molybdenum oxide as hole transporting material for efficient organic solar cell

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Journal of Energy Chemistry 2022年第6期31卷 108-114,I0004页

作者： qian Kang Chenyi Yang Bowei Xu Jianhui hou State Key Laboratory of Polymer Physics and Chemistry Beijing National Laboratory for Molecular SciencesInstitute of Chemistry Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Chemical Resource Engineering College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China

The large energy barrier in hole extraction still remains a great challenge in developing hole transporting layer (HTL) materials for organic solar cells (OSCs).Thus,solution-processed HTL materials with excellent hole collection ability and good compatibility with large-area processing technique are strongly desired for ***,we developed a cost-effective and solution-processed MoO_(3)HTL for efficient *** adding a small amount of glucose as reducing reagent into the ammonium molybdate precursor solution,a deeply n-doped MoO_(3),namely G:Mo,was prepared through the sol–gel *** to pristine MoO_(3),the conductivity of G:Mo was enhanced by two orders of magnitude,which greatly improved the hole collection ability of the *** with G:Mo can exhibit comparable PCE to the PEDOT:PSS *** PBDB-TF:BTP-eC9 as the active layer,a PCE of 17.1%is obtained for the device,which is the highest PCE value for OSC using a solution-processed MoO_(3)*** importantly,G:Mo is well compatible with the blade-coating *** OSC using a blade-coated G:Mo showed almost no PCE loss as compared to the device with spin-coated G:Mo *** results from this work indicate that G:Mo is a promising HTL material for the practical production of OSCs.

关键词： Printable n-doping Molybdenum oxide High conductivities Anode interlayers

Learning hyperspectral images from RGB images via a coarse-to-fine CNN

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Science China(Information Sciences) 2022年第5期65卷 51-64页

作者： Shaohui MEI Yunhao GENG Junhui hou qian DU School of Electronics and Information Northwestern Polytechnical University Department of Electrical and Computer Engineering Mississippi State University Department of Computer Science City University of Hong Kong

Hyperspectral remote sensing is well-known for its extraordinary spectral distinguishability to discriminate different materials. However, the cost of hyperspectral image(HSI) acquisition is much higher compared to traditional RGB imaging. In addition, spatial and temporal resolutions are sacrificed to obtain very high spectral resolution owing to the limitations of sensor technologies. Therefore, in this paper, HSIs are reconstructed using easily acquired RGB images and a convolutional neural network(CNN). As a result,high spatial and temporal resolution RGB images can be inherited to HSIs. Specifically, a two-stage CNN,referred to as the spectral super-resolution network(SSR-Net), is designed to learn the transformation model between RGB images and HSIs from training data, including a band prediction network(BP-Net) to estimate hyperspectral bands from RGB images and a refinement network(RF-Net) to further reduce spectral distortion in the band prediction step. As a result, the learned joint features in the proposed SSR-Net can directly predict HSIs from their corresponding scenes in RGB images without prior knowledge. Experimental results obtained on several benchmark datasets demonstrate that the proposed SSR-Net outperforms several state-of-the-art methods by ensuring higher quality in HSI reconstruction, and significantly improves the performance of traditional RGB images in classification.

关键词： hyperspectral reconstruction convolutional neural network deep learning

Multi-target tracking algorithm based on PHD filter against multi-range-false-target jamming

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Journal of Systems Engineering and Electronics 2020年第5期31卷 859-870页

作者： TIAN Chen PEI Yang hou Peng ZHAO qian School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China

Multi-range-false-target(MRFT) jamming is particularly challenging for tracking radar due to the dense clutter and the repeated multiple false targets. The conventional association-based multi-target tracking(MTT) methods suffer from high computational complexity and limited usage in the presence of MRFT *** order to solve the above problems, an efficient and adaptable probability hypothesis density(PHD) filter is proposed. Based on the gating strategy, the obtained measurements are firstly classified into the generalized newborn target and the existing target measurements. The two categories of measurements are independently used in the decomposed form of the PHD filter. Meanwhile,an amplitude feature is used to suppress the dense clutter. In addition, an MRFT jamming suppression algorithm is introduced to the filter. Target amplitude information and phase quantization information are jointly used to deal with MRFT jamming and the clutter by modifying the particle weights of the generalized newborn targets. Simulations demonstrate the proposed algorithm can obtain superior correct discrimination rate of MRFT, and high-accuracy tracking performance with high computational efficiency in the presence of MRFT jamming in the dense clutter.

关键词： multi-range-false-target(MRFT)jamming multi-target tracking(MTT) probability hypothesis density(PHD) target amplitude feature gating strategy