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Optimization of Fixture Number in Large Thin-Walled Parts Assembly Based on IPSO

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 213-227页

作者： Changhui liu Jing Wang ying zheng Ke Jin Jianbo Yu Jianfeng liu School of Mechanical Engineering Tongji UniversityShanghai 201804China Shanghai Jiaotong University Shanghai 200240China Shanghai Waigaoqiao Shipbuilding Co. Ltd.Shanghai 200137China

There are lots of researches on fixture layout optimization for large thin-walled *** researches focus on the positioning problem,i.e.,optimizing the positions of a constant number of ***,how to determine the number of fixtures is *** most cases,the number of fixtures located on large thin-walled parts is determined based on engineering experience,which leads to huge fixture number and extra ***,this paper constructs an optimization model to minimize the number of *** constraints are set in the optimization model to ensure that the part deformation is within the surface profile *** addition,the assembly gap between two parts is also *** conduct the optimization,this paper develops an improved particle swarm optimization(IPSO)algorithm by integrating the shrinkage factor and adaptive inertia *** the algorithm,particles are encoded according to the fixture *** dimension of the particle is assigned to a sub-region by constraining the optional position range of each fixture to improve the optimization ***,a case study on ship curved panel assembly is provided to prove that our method can optimize the number of fixtures while meeting the assembly quality *** research proposes a method to optimize the number of fixtures,which can reduce the number of fixtures and achieve deformation control at the same time.

关键词： Assembly quality Large thin-walled parts Fixture layout PSO FEM

New species of spongillafly genus Sisyra Burmeister,1839(Neuroptera:Sisyridae)from China and Laos

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Zoological Systematics 2024年第2期49卷 129-142页

作者： ying Yang Yuchen zheng Xingyue liu Department of Entomology China Agricultural UniversityBeijing 100193China

Three new spongillafly species of Sisyra Burmeister,1839 from southern China and Laos are described,namely *** ***.,*** ***.,and *** ***,*** *** *** *** remarkable forewing marking pattern,which has never been reported in ***,the male of the rare species Sisyra yunana Yang,1986 is described for the first *** these Sisyra species have a highly specialized male gonocoxites 9.

关键词： Aquatic insects Neuropterida taxonomy

Fast,simple,efficient Agrobacterium rhizogenes-mediated transformation system to non-heading Chinese cabbage with transgenic roots

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Horticultural Plant Journal 2024年第2期10卷 450-460页

作者： Huiyu Wang Yushan zheng Qian Zhou ying Li Tongkun liu Xilin Hou State Key Laboratory of Crop Genetics&Germplasm Enhancement Key Laboratory of Biology and Genetic Improvement of Horticultural Crops(East China)Ministry of Agriculture and Rural Affairs of ChinaEngineering Research Center of Germplasm Enhancement and Utilization of Horticultural CropsMinistry of Education of ChinaNanjing Agricultural UniversityNanjingJiangsu 210095China Nanjing Suman Plasma Engineering Research Institute Nanjing Agricultural UniversityNanjingJiangsu 210095China

Non-heading Chinese cabbage, a variety of Brassica campestris, is an important vegetable crop in the Yangtze River Basin of China. However,the immaturity of its stable transformation system and its low transformation efficiency limit gene function research on non-heading Chinese cabbage. Agrobacterium rhizogenes-mediated(ARM) transgenic technology is a rapid and effective transformation method that has not yet been established for non-heading Chinese cabbage plants. Here, we optimized conventional ARM approaches(one-step and two-step transformation methods) suitable for living non-heading Chinese cabbage plants in nonsterile environments. Transgenic roots in composite non-heading Chinese cabbage plants were identified using phenotypic detection, fluorescence observation, and PCR analysis. The transformation efficiency of a two-step method on four five-day-old non-heading Chinese cabbage seedlings(Suzhouqing, Huangmeigui, Wuyueman, and Sijiu Caixin) was 43.33%-51.09%, whereas using the stout hypocotyl resulted in a transformation efficiency of 54.88% for the 30-day-old Sijiu *** one-step method outperformed the two-step method;the transformation efficiency of different varieties was above 60%, and both methods can be used to obtain transgenic roots for functional studies within one month. Finally, optimized ARM transformation methods can easily,quickly, and effectively produce composite non-heading Chinese cabbage plants with transgenic roots, providing a reliable foundation for gene function research and non-heading Chinese cabbage genetic improvement breeding.

关键词： Agrobacterium rhizogenes Non-heading Chinese cabbage Transgenic roots Composite plant Transformation efficiency

Microscale spherical TiO_(2)powder prepared by hydrolysis of TiCl_(4)solution:Synthesis and kinetics

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Particuology 2024年第1期84卷 60-71页

作者： Peiyi Yan ying Zhang Shili zheng School of Rare Earths University of Science and Technology of ChinaHefei230026China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341119China Key Laboratory of Green Process and Engineering National Engineering Research Center of Green Recycling for Strategic Metal ResourcesInstitute of Process EngineeringChinese Academy of SciencesBeijing100190China State Key Laboratory of Vanadium and Titanium Resources Comprehensive Utilization Panzhihua617000China

Hydrolysis of TiCl_(4)solution is capable of preparing microscale TiO_(2)*** research studied the synthesis of microscale spherical TiO_(2)powders and the hydrolysis *** effects of the flow field generated by different agitators and baffles in the crystallizer,the initial free acid concentration,the initial equivalent TiO_(2)concentration,and the temperature on the hydrolysis progress and powder morphology were systematically *** results show that the flow field in a crystallizer can significantly affect the morphology and particle size of the powders,and the axial flow can improve the sphericity of the *** increased free HCl and equivalent TiO_(2)concentrations in the pregnant solution inhibit the forward hydrolysis reaction,prolong the time to reach equilibrium,and reduce the *** appropriate temperature matching the compositions of the pregnant solution is crucial for the powder morphology and *** with sizes ranging from around 5 um-40μm can be tuned under controlled flow field,solution compositions,and temperature *** addition,the Cheng and Wunderlich modified Avrami equation was used for the crystallization kinetic *** effects of the free HCl concentration,equivalent TiO_(2)concentration,and hydrolysis temperature are reflected in the reaction rate constant and active nuclei reduction *** the free HCl and equivalent TiO_(2)concentrations will reduce the reaction rate constant and accelerate the deactivation of the active nuclei,thus increasing the final powder size,while increasing the temperature will lead to the opposite results.

关键词： TiCl_(4) Hydrolysis Microscale TiO_(2) Spherical Kinetics

RECENT PROGRESS ON PARTICLE IMAGE VELOCIMETRY IN CHINA

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Journal of Hydrodynamics 2006年第1期18卷 11-19页

作者： liu ying-zheng CAO Zhao-min School of Mechanical and Power Engineering Shanghai Jiaotong University Shanghai 200030 China

An up-to-date review of recent progress on Particle Image Velocimetry （PIV） instrumentations was extensively presented in the paper. Around 80 literatures were referenced. Among various aspects of PIV advances, the present concern was mainly placed on progresses of advanced algorithms and microscopic PIV. Attention was specifically directed toward contributions of domestic researchers to these subjects, which were stressed throughout the discussion. In addition, diverse applications of PIV technology in China, e. g., turbulence measurement, hydrodynamics, rotating flows, two-phase flows, were specifically summarized.

关键词： Particle Image Velocimetry (PIV) algorithm microscopic PIV review

MEASUREMENT OF A WALL-BOUNDED TURBULENT MIXING LAYER FLOW

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Journal of Hydrodynamics 2005年第6期17卷 681-685页

作者： KE Feng liu ying-zheng CHEN Han-ping School of Mechanical and Power Engineering Shanghai jiaotong University Shanghai 200030 China

Turbulence properties of a wall bounded turbulent mixing layer associated with an opening step were extensively measured using I-and X-type hntwires. The turbu lent mixing layer flow was analyzed in terms of wall static pressure distribution, turbulence intensity, Reynolds stress, streamwise velocity profile and continuous wavelet transform coefficients, Development of vortical structures embedded in the turbulent mixing layer was temporally and spatially re solved by using continuous wavelet transform. The constraint of the downstream solid wall on the mixing layer flow was de lineated.

关键词： turbulent flow mixing layer coherent structure

AN EXPERIMENTAL STUDY OF FLOW AROUND A BIO-INSPIRED AIRFOIL AT REYNOLDS NUMBER 2.0×10~3

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Journal of Hydrodynamics 2012年第3期24卷 410-419页

作者： SHI Sheng-xian liu ying-zheng CHEN Jian-min Key Laboratory of Education Ministry for Power Machinery and Engineering School of Mechanical EngineeringShanghai Jiao Tong University Shanghai 200240 China

The fluid flow around a bio-inspired airfoil with corrugated surfaces and its smooth counterpart at chord Reynolds number Re = 2.0×10^3. and different Angle-Of-Attack （AOA = 0°, 4°, 8° and 12°） were measured by using Particle Image Velocimetry （PIV）. The global characteristics of the fluid flow around two airfoils were analyzed by ensemble-averaged velocity field, distribution of reverse flow intermittency, and time-series flow visualizations. At AOA = 0°, no significant variation of the global flow patterns was recognized for both configurations. The statistical results of reverse flow intermittency results demonstrated that the protruding peaks of the corrugated airfoil delay flow separation occur at AOA = 4°. At large AOAs （8° and 12°）, however, the flow is massively separated in both configurations, the combination of large separation bubble above the corrugated airfoil and small recirculation zones in the upstream upper valley results in earlier separation of the flow. At AOA=8°, the wake region behind the corrugated airfoil is considerably shortened in comparison to the smooth one, indicating a remarkable reduction of the time-mean lift and drag forces, however, at AOA - 12°, the wake region behind the corrugated one is slightly larger than that behind the smooth one. For the case of AOA = 8° and 12°, the time-series flow visualizations demonstrate the intensified vortex shedding process of the corrugated airfoil, which would give rise to enhanced dynamic loading. Due to the fact that dragonfly wing is practically flexible, it is speculated that the wing structure of a gliding dragonfly might be sophisticatedly deformed in response to the periodic loading to reduce the drag.

关键词： corrugated airfoil separated flow Particle Image Velocimetry (PIV) dragonfly gliding flight

Clinical applications of metagenomics next-generation sequencing in infectious diseases

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第6期25卷 471-484页

作者： ying liu Yongjun MA Department of Clinical Laboratory Affiliated Jinhua HospitalZhejiang University School of MedicineJinhua 321000China

Infectious diseases are a great threat to human *** and accurate detection of pathogens is important in the diagnosis and treatment of infectious *** next-generation sequencing(mNGS)is an unbiased and comprehensive approach for detecting all RNA and DNA in a *** the development of sequencing and bioinformatics technologies,mNGS is moving from research to clinical application,which opens a new avenue for pathogen *** studies have revealed good potential for the clinical application of mNGS in infectious diseases,especially in difficult-to-detect,rare,and novel ***,there are several hurdles in the clinical application of mNGS,such as:(1)lack of universal workflow validation and quality assurance;(2)insensitivity to high-host background and low-biomass samples;and(3)lack of standardized instructions for mass data analysis and report ***,a complete understanding of this new technology will help promote the clinical application of mNGS to infectious *** review briefly introduces the history of next-generation sequencing,mainstream sequencing platforms,and mNGS workflow,and discusses the clinical applications of mNGS to infectious diseases and its advantages and disadvantages.

关键词： Metagenomics next-generation sequencing(mNGS) Infectious disease Cerebrospinal fluid(CSF) Oxford Nanopore Technologies(ONT) Microbiome

Neighborhood predictors of short sleep duration and bedtime irregularity among children in the United States: results from the 2019-2020 National Surveyof Children's Health

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World Journal of Pediatrics 2024年第1期20卷 73-81页

作者： ying Dai Jianghong liu School of Nursing University of Pennsylvania418 Curie Blvd.Room 426Claire M.Fagin HallPhiladelphiaPA19104-6096USA

Background Environmental factors may contribute to short sleep duration and irregular bedtime in *** factors and children's sleep duration and bedtime regularity remain a less investigated *** aim of this study was to investigate the national and state-level proportions of children with short sleep duration and irregular bedtime and their neighborhood *** A total of 67,598 children whose parents completed the National Survey of Children's Health in 2019-2020 were included in the ***-weighted Poisson regression was used to explore the neighborhood predictors of children's short sleep duration and irregular *** The prevalence of short sleep duration and irregular bedtime among children in the United States(US)was 34.6%[95%confidence interval(CI)=33.8%-35.4%]and 16.4%(95%CI=15.6%-17.2%)in 2019-2020,*** neighborhoods,supportive neighborhoods,and neighborhoods with amenities were found to be protective factors against children's short sleep duration,with risk ratios ranging between 0.92 and 0.94,P<*** with detracting elements were associated with an increased risk of short sleep duration[risk ratio(RR)=1.06,95%CI=1.00-1.12]and irregular bedtime(RR=1.15,95%CI=1.03-1.28).Child race/ethnicity moderated the relationship between neighborhood with amenities and short *** Insufficient sleep duration and irregular bedtime were highly prevalent among US children.A favorable neighborhood environment can decrease children's risk of short sleep duration and irregular *** the neighborhood environment has implications for children's sleep health,especially for children from minority racial/ethnic groups.

关键词： Child National Survey of Children's Health Neighborhood.Sleep Social determinants of health