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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

New Thymol Derivate from Centipeda minima

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Chemical Research in Chinese Universities 2009年第1期25卷 125-126页

作者： PU Shou-cheng GUO yuan-qiang GAO Wen-yuan ZHANG Tie-jun School of Pharmaceutical Science and Technology Tianjin University Tianjin 300072 P. R. China Department of Pharmaceutical Sciences Nankai University Tianjin 300071 P. R. China Tianjin Institute of Pharmaceutical Research Tianjin 300193 P. R. China

1 Introduction Centipeda minima（Compositae） is an annual herbaceous plant found in moist places throughout the plains mainly in the southern regions of the People＇s Republic of China, Eastern tropical Asia, Australia and the Pacific Islands. It is a commonly used Chinese folk medicine for colds, whooping cough, nasal allergy, malaria and asthma. A number of sesquiterpene lactones, flavonoids and triterpenes have previously been isolated from C. minima. During our study on searching for biological active components from this plant,

关键词： Centipeda minima Thymol derivate Thymohydroquinone 6-O-β-6'-acetyl-Glc

Volume Gain of Brainstem on Medication-Overuse Headache Using Voxel-Based Morphometry

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Chinese Medical Journal 2018年第18期131卷 2158-2163页

作者： Zhioye Chen xiao-Yan Chen Meng-Qi Liu Lin Ma Sheng-yuan Yu Department of Radiology Chinese People's Liberation Army General Hospital Beijing 100853 China Department of Radiology Hainan Branch of Chinese People's Liberation Army General Hospital Sanya Hainan 572013 China Department of Neurology Chinese People's Liberation Army General Hospital Beijing 100853 China

Background： Histopathology identified the anatomical and molecular abnormalities ofbrainstem nuclei in migraine patients. However, the exact whole brainstem structural changes in vivo have not yet been identified in medication-overuse headache （MOH） transformed from migraine. The aim of this study was to investigate the regional volume changes over the whole brainstem in the MOH patients using voxel-based morphometry （VBM） in ***： High-resolution three-dimensional structural images were obtained using a 3.0-Tesla magnetic resonance system from 36 MOH patients and 32 normal controls （NCs） who were consecutively recruited from the International Headache Center, Chinese People＇s Liberation Army General Hospital, from March 2013 to June 2016. VBM was used to assess the brainstem structural alteration in the MOH patients, and voxel-wise correlation was performed to evaluate the relationship with the clinical ***： The brainstem region with increased volume located in the left ventrolateral periaqueductal gray （MNI coordinate： -1, -33, -8）, ventral tegmental area （MNI coordinate： 0, -22, - 12）, bilateral substantia nigra （MNI coordinate： -8, - 16, - 12, 9, - 16, - 12）, and trigeminal root entry zone （MNI coordinate： -19, -29, -31; 19, -32, -29） in MOH patients compared with NCs. The headache visual analog scale score was positively related with the left rostral ventromedial medulla （RVM）（MNI coordinate： -1, -37, -56; cluster size： 20; r = 0.602） in the MOH ***： The regional volume gain ofbrainstem could underlie the neuromechanism of impaired ascending and descending pathway in the MOH patients, and the left RVM volume alteration could imply the impaired tolerance ofnociceptive pain input and could be used to assess the headache disability in the MOH patients.

关键词： Medication-Overuse Headache Substantia Nigra Trigeminal Root Entry Zone Ventral Tegmental Area Voxel-Based Morphometry

Promoting Government Supervision and Optimizing Government Service Innovation

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学术界 2017年第11期 278-285页

作者： yuan Weihai Anhui Administration Institute

Decentralization and strengthening supervision are the two wings of the reform of administrative examination and approval system. At present, in the supervision process of Chinese government, the phenomenon of strict approval and slack supervision still exists in some local governments. And the dynamic supervision mechanism and supervision restriction mechanism of some local governments are still not perfect. These problems directly lead to"regulatory vacuum"and service absence and other circumstances. The existence of these circumstances will block the process of China's administrative examination and approval system reform. As a result to explore how to promote government supervision innovation and optimize government services is the first important thing, and then to create conditions for the rapid, stable and orderly progress of the administrative examination,what's more to approval system *** on this thesis, the author realizes legal supervision, implement informatization *** not only has increased normalized supervision, improve the administrative examination and approval all-round supervision mechanism, but also established the third party assessment normalization mechanism, and optimize the administrative examination and approval policy advocacy mechanism as well.

关键词： decentralization administrative examination and approval supervision innovation service optimization

Numerical simulation of hypersonic thermochemical nonequilibrium flows using nonlinear coupled constitutive relations

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Chinese Journal of Aeronautics 2023年第3期36卷 63-79页

作者： Shuhua ZENG Zhenyu yuan Wenwen ZHAO Weifang CHEN School of Aeronautics and Astronautics Zhejiang UniversityHangzhou 310027China School of Energy and Power Engineering Nanjing University of Science and TechnologyNanjing 210094China

To predict aeroheating performance of hypersonic vehicles accurately in thermochemical nonequilibrium flows accompanied by rarefaction effect,a Nonlinear Coupled Constitutive Relations(NCCR)model coupled with Gupta’s chemical models and Park’s two-temperature model is firstly proposed in this *** typical cases are intensively investigated for further validation,including hypersonic flows over a two-dimensional cylinder,a RAM-C II flight vehicle and a type HTV-2 flight *** results predicted by NCCR solution,such as heat flux coefficient and electron number densities,are in better agreement with those of direct simulation Monte Carlo or flight data than Navier-Stokes equations,especially in the extremely nonequilibrium regions,which indicates the potential of the newly-developed solution to capture both thermochemical and rarefied nonequilibrium *** comparisons between the present solver and NCCR model without a two-temperature model are also conducted to demonstrate the significance of vibrational energy source term in the accurate simulation of high-Mach flows.

关键词： Hypersonic flow Nonlinear coupled constitutive relations Rarefied gas Thermochemical nonequilibrium effect Vibrational excitation

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移动协同编辑中基于CRDT的序列转换算法

华中科技大学学报（自然科学版） 2022年第2期50卷 130-135页

作者：吕晓苑佳存贲可荣程媛海军工程大学电子工程学院湖北武汉430033 武汉大学信息管理学院湖北武汉430072

为高效地处理移动协同编辑中用户积累的大量本地操作,实现移动协同编辑系统的高响应性,提出一种支持序列转换的可交换复制数据类型(commutative replicated data type,CRDT)算法.首先,提出一个移动协同编辑的总体框架,支持多个移动终端... 详细信息

为高效地处理移动协同编辑中用户积累的大量本地操作,实现移动协同编辑系统的高响应性,提出一种支持序列转换的可交换复制数据类型(commutative replicated data type,CRDT)算法.首先,提出一个移动协同编辑的总体框架,支持多个移动终端离线或在线地协同编辑共享文档副本;然后,提出一个支持序列转换的移动协同编辑算法,可以实现离线操作中多个首尾连接的顺序插入操作的自动转换和操作效果的合并,维护移动协同编辑中共享文档副本的一致性.相关实验表明所提出的算法在响应性和功耗方面优于典型的一致性维护方法.

关键词：交换复制数据类型(CRDT) 一致性维护移动协同编辑操作序列能耗

Single image super-resolution reconstruction using multiple dictionaries and improved iterative back-projection

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Optoelectronics Letters 2019年第2期15卷 156-160页

作者： ZHAO Jian-wen yuan Qi-ping QIN Juan YANG xiao-ping CHEN Zhi-hong Tianjin Key Laboratory of Film Electronic and Communication Devices School of Electrical and Electronic Engineering Tianjin University of Technology

In order to improve the super-resolution reconstruction effect of the single image, a novel multiple dictionaries learning via support vector regression(SVR) and improved iterative back-projection(IBP) are *** characterize the image structure, the low-frequency dictionary is constructed from the normalized brightness of low-frequency image patches in a discrete-cosine-transform(DCT) *** determined by Gaussian weighting are added to the input vector to restore more high-frequency information when training the high-frequency image patch dictionary in the space *** post-processing, the improved IBP is employed to reduce regression errors each *** results show that the peak signal-to-noise ratio(PSNR)and structural similarity(SSIM) of the proposed method are enhanced by 1.6%—5.5% and 1.5%—13.1% compared with those of bicubic interpolation, and the proposed method visually outperforms several algorithms.

关键词： super-resolution multiple dictionaries

Long-distance spread of Tembusu virus,and its dispersal in local mosquitoes and domestic poultry in Chongming Island,China

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Infectious Diseases of Poverty 2023年第3期12卷 94-95页

作者： yuan Fang Tian Hang Li-Min Yang Jing-Bo Xue Ryosuke Fujita Xue-Song Feng Tian-Ge Jiang Yi Zhang Shi-Zhu Li xiao-Nong Zhou School of Global Health Chinese Center for Tropical Diseases ResearchShanghai Jiao Tong University School of MedicineShanghaiChina National Institute of Parasitic Diseases Chinese Center for Disease Control and Prevention(Chinese Center for Tropical Diseases Research)NHC Key Laboratory of Parasite and Vector BiologyWHO Collaborating Centre for Tropical DiseasesNational Center for International Research on Tropical DiseasesShanghaiChina Laboratory of Sanitary Entomology Faculty of AgricultureKyushu UniversityFukuokaJapan Shanghai Chongming Dongtan National Nature Reserve ShanghaiChina

Background Chongming Island in China serves as a breeding and shelter point on the East Asian–Australasian *** resting frequency of migratory birds,abundance of mosquito populations,and the popular domestic poultry industry pose a potential risk of mosquito-borne zoonotic *** aim of this study is to explore the role of migratory birds in the spread of mosquito-borne pathogens and their prevalent status on the *** We conducted a mosquito-borne pathogen surveillance in 2021,in Chongming,Shanghai,***‑mately 67,800 adult mosquitoes belonging to ten species were collected to investigate the presence of faviviruses,alphaviruses,and orthobunyaviruses by *** and phylogenetic analyses were conducted to explore the virus genotype and potential nature *** survey was performed by ELISA to characterize Tembusu virus(TMUV)infection among domestic *** Two strains of TMUV and Chaoyang virus(CHAOV)and 47 strains of Quang Binh virus(QBV)were detected in 412 mosquito pools,with the infection rate of 0.16,0.16,and 3.92 per 1000 Culex tritaeniorhynchus,***‑thermore,TMUVs viral RNA was found in serum samples of domestic chickens and faecal samples of migratory *** against TMUV were detected in domestic avian serum samples,generally ranging from 44.07%in pigeons to 55.71%in *** analyses indicated that the TMUV detected in Chongming belonged to Cluster 3,Southeast Asia origin,and most closely related to the CTLN strain,which caused a TMUV outbreak in chickens in Guangdong Province in 2020,but distant from strains obtained previously in Shanghai,which were involved in the 2010 TMUV outbreak in *** We speculate that the TMUV was imported to Chongming Island through long-distance spreading by migratory birds from Southeast Asia,followed by spill over and transmission in mosquitoes and domestic avian species,threatening the local domestic *** addition,the exp

关键词： Chaoyang virus Emerging zoonotic vector-borne disease Insect-specifc favivirus Mosquito-borne virus Quang Binh virus

Slab Storage Calculation Method for Continuous Casting-Hot Rolling

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Journal of Iron and Steel Research International 2004年第1期11卷 33-36页

作者： PENGQi-chun LIUQing TIANNai-yuan WuhanUniversityofScienceandTechnology Wuhan430081China UniversityofScienceandTechnologyBeijing Beijing100083China

Based on load-oriented manufacturing control theory,different combining modes and slab storage calculation method for continuous casting and hot rolling were *** buffer capacity index of continuous casting-rolling was introduced,and the reasonable slab storage under different combining modes was calculated with buffer capacity index of 120.00 hfor CCR,79.20 hfor HCR,19.68 hfor DHCR and 3.84 hfor *** slab is 1.20 h,and the strip is *** gist was provided for steel enterprise to decrease storage.

关键词： continuous casting hot rolling production control slab storage