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Spatial relation between fluctuating wall pressure and near-wall streamwise vortices in wall bounded turbulent flow

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Applied Mathematics and Mechanics(English Edition) 2015年第6期36卷 719-728页

作者： Mingwei GE Yingtao ZUO Ying DENG yuhua li State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power University School of Aeronautics Northwestern Polytechnical University

A new view of the spatial relation between fluctuating wall pressure and near-wall streamwise vortices （NWSV） is proposed for wall bounded turbulent flow by use of the direct numerical simulation （DNS） database. The results show that the wall region with low pressure forms just below the strong NWSV, which is mostly associated with the overhead NWSV. The wall region with high pressure forms downstream of the NWSV, which has a good correspondence with the downwash of the fluids induced by the upstream NWSV. The results provide a significant basis for the detection of NWSV.

关键词： conditional correlation fluctuating wall pressure streamwise vortices

Type-2 fuzzy description logic

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Frontiers of Computer Science 2011年第2期5卷 205-215页

作者： Ruixuan li Kunmei WEN Xiwu GU yuhua li Xiaolin SUN Bing li Intelligent and Distributed Computing Laboratory School of Computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 China State Key Laboratory of Software Engineering Wuhan University Wuhan 430072 China

Description logics （DLs） are widely employed in recent semantic web application systems. However, classical description logics are limited when dealing with imprecise concepts and roles, thus providing the motivation for this work. In this paper, we present a type-2 fuzzy attributive concept language with complements （ALC） and provide its knowledge representation and reasoning algorithms. We also propose type-2 fuzzy web ontology language （OWL） to build a fuzzy ontology based on type- 2 fuzzy ALC and analyze the soundness, completeness, and complexity of the reasoning algorithms. Compared to type-1 fuzzy ALC, type-2 fuzzy ALC can describe imprecise knowledge more meticulously by using the membership degree interval. We implement a semantic search engine based on type-2 fuzzy ALC and carry out experiments on real data to test its performance. The results show that the type-2 fuzzy ALC can improve the precision and increase the number of relevant hits for imprecise information searches.

关键词： description logic (DL) type-2 fuzzy attributive concept language with complements (ALC) fuzzy ontology reasoning semantic search engine

Design and test of the plant-correcting reel for harvesting lodging garlic plants

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 59-68页

作者： yuhua li Chao li Lupeng liu Kai Zhou Jialin Hou College of Mechanical and Electronic Engineering Shandong Agricultural UniversityTai’an 271018ShandongChina College of Biosystems Engineering&Food Science Zhejiang UniversityHangzhou 310058China

Crops are prone to lodging with the decline of stem moisture and the intervention of other factors in the mature harvest period,such as garlic,which is difficult to harvest *** solve this problem,the plant-correcting reel for harvesting lodging garlic plants,bumped and deformed with plants many times to pull and lift them into a conveyor,is proposed in this *** analyzed the motion trajectory equation and key influencing factors of the reel and defined the lifting and plant-correcting stages as three processes of contact,stirring and *** example,the contact deformation model and system energy equations were established in the contact ***,in the stirring process,the garlic plant-correcting conditions were established through the dynamic simulation test analysis of garlic seedling trajectories and the deflection model of garlic stem was ***,in the release process,the expressions of rubber bars rotation and garlic plant offset bending curvature were constructed and the optimal number and distribution form of bars were ***,the mechanism and key operating parameters of the auxiliary lifting mechanism of the divider were *** the single-factor test,the influence of reel speed,forward speed and reel height on the success feeding rate was analyzed under different bars distribution forms;Through multi-factor experiments,the interaction contour map of various factors was *** reel speed,forward speed and reel height were 3 rad/s,3.5 m/s,and 540 mm,the feeding success rate was 98.73%.The optimization factors were tested and verified,which met the operational requirements of a high feeding success rate and low loss rate of garlic *** study combines laboratory virtual as well as field experiments and analyzes of trajectory of bars,contact deformation and deflection model of garlic plant,and reel rotation and garlic plant offset bending curvature to solve the problem of ga

关键词： feeding success rate lodging garlic harvesting reel plant model field test

C60 Fullerenes Suppress Reactive Oxygen Species Toxicity Damage in Boar Sperm

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Nano-Micro Letters 2019年第4期11卷 817-833页

作者： Xinhong li lirui Wang Huan liu Jieli Fu linqing Zhen yuhua li Yaozhong Zhang Yafei Zhang Shanghai Key Laboratory of Veterinary Biotechnology School of Agriculture and BiologyShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Institute of Nano Biomedicine and Engineering Shanghai Engineering Research Centre for Intelligent Diagnosis and Treatment InstrumentDepartment of Instrument Science and EngineeringSchool of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Department of Electrical and Computer Engineering Michigan State UniversityEast LansingUSA Key Laboratory of Thin Film and Microfabrication(Ministry of Education) Department of Micro/Nano ElectronicsSchool of ElectronicsInformation and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

We report the carboxylated C60 improved the survival and quality of boar sperm during liquid storage at 4°C and thus propose the use of carboxylated C60 as a novel antioxidant semen extender *** results demonstrated that the sperm treated with 2μg mL?1 carboxylated C60 had higher motility than the control group(58.6%and 35.4%,respectively;P?0.05).Moreover,after incubation with carboxylated C60 for 10 days,acrosome integrity and mitochondrial activity of sperm increased by 18.1%and 34%,respectively,compared with that in the control ***,the antioxidation abilities and adenosine triphosphate levels in boar sperm treated with carboxylated C60 significantly increased(P?0.05)compared with those in the control *** presence of carboxylated C60 in semen extender increases sperm motility probably by suppressing reactive oxygen species(ROS)toxicity ***,carboxylated C60 could protect boar sperm from oxidative stress and energy deficiency by inhibiting the ROS-induced protein dephosphorylation via the cAMP-PKA signaling *** addition,the safety of carboxylated C60 as an alternative antioxidant was also comprehensively evaluated by assessing the mean litter size and number of live offspring in the carboxylated C60 treatment *** findings confirm carboxylated C60 as a novel antioxidant agent and suggest its use as a semen extender supplement for assisted reproductive technology in domestic animals.

关键词： Carboxylated C60 Semen preservation Oxidative stress Motility Protein dephosphorylation

A novel cold-inducible promoter,PThCAP from Tamarix hispida,confers cold tolerance in transgenic Arabidopsis thaliana

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Journal of Forestry Research 2018年第2期29卷 330-336页

作者： Xiaohong Guo Yandong Lv Hongyu li Nan Fu Guiping Zheng lihua liu yuhua li State Key Laboratory of Tree Genetics and Breeding Northeast Forestry University Key Laboratory of Modern Agricultural Cultivation and Crop Germplasm Improvement of Heilongjiang Province Agronomy College Heilongjiang Bayi Agricultural University College of life Science and Technology Heilongjiang Bayi Agricultural University College of life Sciences Daqing Bio-tech Research InstituteNortheast Forestry University

Our previous studies have revealed that the Th CAP gene plays a vital role in transgenic Populus(*** 9 ***) in response to cold ***,the regulatory mechanism of Th CAP gene expression has been *** this study,the 50 flanking region of the Th CAP promoter(PTh CAP) was cloned using a genomewalking *** analyzing cis-acting regulatory elements of PTh CAP,a DRE motif and MYC and MYB elements were found to be located in the *** identify the regulatory elements that control the expression of the Th CAP gene promoter,a series of deletion derivatives ofPTh CAP,P1–P5,from the translation start code(-1538,-1190,-900,-718 and-375 bp),were fused to the GUS reporter gene,and then each deletion was stably introduced into Arabidopsis thaliana *** analysis of the promoter suggested that only the P2 fragment had strong GUS expression in leaves and roots of *** exposed to low temperature *** results suggest that this290-bp region(-1190 to-900 bp),as an important part in PTh CAP,was associated with cold tolerance of *** results provide evidence for the regulatory mechanism of Th CAP gene involved in the response to cold stress,and that the gene is promising candidate gene for genetic improvement of crops.

关键词： Arabidopsis thaliana Cis-acting elements GUS expression PThCAP ThCAP gene

Network Defense Decision-Making Based on Deep Reinforcement Learning and Dynamic Game Theory

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China Communications 2024年第9期21卷 262-275页

作者： Huang Wanwei Yuan Bo Wang Sunan Ding Yi li yuhua College of Software Engineering Zhengzhou University of Light IndustryZhengzhou 450001China The Third Construction Co. Ltd of China CREC Railway Electrification Engineering GroupZhengzhou 450052China Electronic and Communication Engineering Shenzhen Polytechnic UniversityShenzhen 518055China

Existing researches on cyber attackdefense analysis have typically adopted stochastic game theory to model the problem for solutions,but the assumption of complete rationality is used in modeling,ignoring the information opacity in practical attack and defense scenarios,and the model and method lack *** such problem,we investigate network defense policy methods under finite rationality constraints and propose network defense policy selection algorithm based on deep reinforcement *** on graph theoretical methods,we transform the decision-making problem into a path optimization problem,and use a compression method based on service node to map the network *** this basis,we improve the A3C algorithm and design the DefenseA3C defense policy selection algorithm with online learning *** experimental results show that the model and method proposed in this paper can stably converge to a better network state after training,which is faster and more stable than the original A3C *** with the existing typical approaches,Defense-A3C is verified its advancement.

关键词： A3C cyber attack-defense analysis deep reinforcement learning stochastic game theory

Artificial Shiro formation of Tricholoma matsutake

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Frontiers in Biology 2006年第3期1卷 230-235页

作者： LUN Zhiming li yuhua XING Shutang Vaario Lumin Institute of Flower Biotechnology Northeast Forestry UniversityHarbin 150040China Department of Green Agriculture Heilongjiang Professional College of Agricultural EconomyMudanjiang 157041China

One type of soil collected from Maoer-shan in Heilongjiang Province,China was selected to induce hyphal growth of Tricholoma matsutake by a soil screening *** was confirmed that hyphal growth of all the tested *** isolates was significantly stimulated in soil by supplemented with 0.5%~2.0%olive *** ag-gregation of hyphae and soil resembled natural *** biomass of hyphae in the soil increases with increasing olive oil ***,seedlings of Pinus den-siflora grew well in the soil containing 0.5%~1.0%olive oil and were also successfully infected by *** isolate A in the soil containing 1.0%olive *** study estab-lished a culture system of artificial Shiro formation and also provided a premise for formulation of culture substratum for fruit body formation of ***.

关键词： soil screening olive oil biomass of hyphae

Microstructure evolution of AZ91 alloy processed by a combination method of equal channel angular pressing and rolling

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Journal of Magnesium and Alloys 2020年第1期8卷 192-198页

作者： Qiong Xu Aibin Ma yuhua li Jiapeng Sun Yuchun Yuan Jinghua Jiang Chaoying Ni College of Mechanics and Materials Hohai UniversityNanjing 211100China Department of Materials Science&Engineering University of DelawareDE 19716USA Suqian Institute of Hohai University Suqian 223800China

In the present work,AZ91 alloy was successfully processed by equal channel angular pressing(ECAP)for up to 16 passes and rolling(R)for multiple passes with a total reduction of 75%in addition to a combination method with ECAP plus rolling(ECAP+R).The effects of various processes(ECAP,R and ECAP+R)on microstructure evolution were analyzed and the influence of ECAP process on the rolling performance was *** result shows that ECAP contributed to a homogenous grain structure and formed a texture with higher Schmidt factors that was easy for rolling.A plate with smoother surface and reduced edge cracks was observed in the ECAP+R process than in the single R *** the microstructure of the alloy was similar after ECAP+R and R process,the sample of ECAP+R was more refined and had stronger second phase precipitation than the sample of R,which resulted in better rolling characteristics,along with the external surfaces.

关键词： AZ91 alloy ECAP and rolling “ECAP-modified”structure Second phase precipitation Texture

Analysis of genetic diversity and differentiation of artificial populations of yellowhorn(Xanthoceras sorbifolium) in China using ISSR markers

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Journal of Forestry Research 2016年第5期27卷 1099-1104页

作者： Chanhoon An Hyunseok Lee Jeonghoon Lee Eun Ju Cheong yuhua li Jae-Seon Yi Herbal Crop Research Division National Institute of Horticultural & Herbal ScienceRural Development Administration Department of Forestry Graduate SchoolKangwon National University Forest Genetic Resources Department National Institute of Forest Science Department of Forest Resources College of Forest and Environmental SciencesKangwon National University Department of Developmental Biology College of Life ScienceNortheast Forestry University

Yellowhorn （Xanthoceras sorbifolium Bunge） is a drought-tolerant tree in the family Sapindaceae that is native to northeastern China. Its remarkably oil-rich seeds are a reliable biodiesel source. An inter simple sequence repeat （ISSR） analysis showed genetic variation among four artificial populations in China： two in Inner Mongolia （IM）, one in liaoning （LN）, and one in Shandong （SD）. The average percentage of polymorphic loci was 81.25 % for these four populations. The Forest Farm in SD showed the highest number of effective alleles （Ne）, Shannon index （I）, and expected heterozygosity （He）, i.e., 1.598, 0.470, and 0.325, respectively, but the lowest number of alleles （Na） as 1.600. Based on an analysis of molecular variance, 23 % of the total genetic variation was found among populations, and 77 % within populations. A principal coordinate analysis revealed two groups （Group 1： lindonglinchang, Jianping Agriculture Research Station and Forest Farm; Group 2： Jinjilinchang）. Understanding the genetic diversity among artificial yellowhorn populations in China, detected using ISSRs, will be useful for yellowhorn conservation and improvement. Additional arti-ficial and natural populations need to be included in the future for a country-wide perspective.

关键词： Differentiation - Diversity ISSR Populationstructure Xanthoceras sorbifolium Yellowhorn