检索结果-南通市图书馆

Numerical Simulation of Rotor-aerodynamic Surface Interaction in Hover Using Moving Chimera Grid

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2012年第3期25卷 342-348页

作者： li yibo MA Dongli School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China

Three-dimensional unsteady Navier-Stokes equations are numerically solved to simulate the aerodynamic interaction of rotor, canard and horizontal tail in hover based on moving chimera grid. The variations of unsteady aerodynamic forces and moments of the canard and horizontal tail with respect to the rotor azimuth are analyzed with the deflection angle set at 0° and 50°, respectively. The pressure map of aerodynamic surfaces and velocity vector distribution of flow field are investigated to get better understanding of the unsteady aerodynamic interaction. The result shows that the canard and horizontal tail present different characteristics under the downwash of the rotor. The canard produces much vertical force loss with low amplitude fluctuation. Contrarily, the horizontal tail, which is within the flow field induced by the down wash of the rotor, produces only less vertical force loss, but the amplitudes of the lift and pitching moment are larger, implying that a potential deflection angle scheme in hover is 50° for the canard and 0° for the horizontal tail.

关键词： unsteady flow chimera grid canard rotor/wing aerodynamic interaction numerical simulation

Cellular V2X-Based Integrated Sensing and Communication System:Feasibility and Performance Analysis

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Electronics 2024年第4期33卷 1104-1116页

作者： yibo li Junhui ZHAO Jieyu liAO Fajin HU School of Electronic and Information Engineering Beijing Jiaotong University

Communication and sensing are basically required in intelligent transportation. The combination of two functions can provide a viable way in alleviating concerns about resource limitations. To achieve this, we propose an integrated sensing and communication(ISAC) system based on cellular vehicle-to-everything(C-V2X). We first analyze the feasibility of new radio(NR) waveform for ISAC system. We discuss the possibility of reusing NR waveform for sensing based on current NR-V2X standards. Ambiguity function is calculated to investigate the sensing performance limitation of NR waveform. A C-V2X-based ISAC system is then designed to realize the two tasks in vehicular network simultaneously. We formulate an integrated framework of vehicular communication and automotive sensing using the already-existing NR-V2X network. Based on the proposed ISAC framework, we develop a receiver algorithm for target detection/estimation and communication with minor modifications. We evaluate the performance of the proposed ISAC system with communication throughput, detection probability, and range/velocity estimation *** show that the proposed system achieves high reliability communication with 99.9999% throughput and high accuracy sensing with errors below 1 m and 1 m/s in vehicle scenarios.

关键词： Accuracy Estimation Receivers Reliability theory Integrated sensing and communication Throughput Task analysis

Approximate-model Based Estimation Method for Dynamic Response of Forging Processes

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2015年第3期28卷 565-572页

作者： LEI Jie LU Xinjiang li yibo HUANG Minghui ZOU Wei State Key Laboratory of High Performance Complex Manufacturing Central South University

Many high-quality forging productions require the large-sized hydraulic press machine（HPM） to have a desirable dynamic response. Since the forging process is complex under the low velocity, its response is difficult to estimate. And this often causes the desirable low-velocity forging condition difficult to obtain. So far little work has been found to estimate the dynamic response of the forging process under low velocity. In this paper, an approximate-model based estimation method is proposed to estimate the dynamic response of the forging process under low velocity. First, an approximate model is developed to represent the forging process of this complex HPM around the low-velocity working point. Under guaranteeing the modeling performance, the model may greatly ease the complexity of the subsequent estimation of the dynamic response because it has a good linear structure. On this basis, the dynamic response is estimated and the conditions for stability, vibration, and creep are derived according to the solution of the velocity. All these analytical results are further verified by both simulations and experiment. In the simulation verification for modeling, the original movement model and the derived approximate model always have the same dynamic responses with very small approximate error. The simulations and experiment finally demonstrate and test the effectiveness of the derived conditions for stability, vibration, and creep, and these conditions will benefit both the prediction of the dynamic response of the forging process and the design of the controller for the high-quality forging. The proposed method is an effective solution to achieve the desirable low-velocity forging condition.

关键词： performance analysis forging process modeling hydraulic press machine

Scaffold-based tissue engineering strategies for soft-hard interface regeneration

在线全文

学校读者我要写书评

暂无评论

Regenerative Biomaterials 2023年第1期10卷 107-125页

作者： yibo li Mo Zhou Wenzhuo Zheng Jianying Yang Nan Jiang State Key Laboratory of Oral Diseases National Clinical Research Center for Oral DiseaseWest China Hospital of StomatologySichuan UniversityChengduChina Department of Outpatient nursing West China Second University Hospital&Key Laboratory of Birth Defects and Related Diseases of Women and Children(Sichuan University)Ministry of EducationSichuan UniversityChengduChina

Repairing injured tendon or ligament attachments to bones(enthesis)remains costly and *** superb surgical management,the disorganized enthesis newly formed after surgery accounts for high recurrence rates after *** engineering offers efficient alternatives to promote healing and regeneration of the specialized enthesis ***-transmitting functions thus can be restored with appropriate biomaterials and engineering ***,recent studies have focused more on microstructure especially the arrangement of fibers since Rossetti successfully demonstrated the variability of fiber underspecific external *** this review,we provide an important update on the current strategies for scaffold-based tissue engineering of enthesis when natural structure and properties are equally *** firstly described compositions,structures and features of natural enthesis with their special mechanical properties *** for growth,development and healing of enthesis widely used in popular strategies are systematically *** discuss the fabrication of engineering scaffolds from the aspects of biomaterials,techniques and design strategies and comprehensively evaluate the advantages and disadvantages of each *** last,this review pinpoints the remaining challenges and research directions to make breakthroughs in further studies.

关键词： enthesis tissue engineering interface mechanical properties biomaterials

Viscosity profile prediction of a heavy crude oil during lifting in two deep artesian wells

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2017年第7期25卷 976-982页

作者： yibo li Hao Gao Wanfen Pu Bing Wei Yafei Chen Dong li Qiang Luo State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Research Institute of Experiment and Detection Xinjiang Oilfield CompanyPetroChina

It has been known that the productivity of artesian wells is strongly dependent on the rheological properties of crude oils. This work targets two deep artesian wells(>5000 m) that are producing heavy crude oil. The impacts of well conditions including temperature, pressure and shear rate, on the crude oil rheology were comprehensively investigated and correlated using several empirical rheological models. The experimental data indicate that this heavy oil is very sensitive to temperature as result of microstructure change caused by hydrogen bonding. The rheological behavior of the heavy oil is also significantly impacted by the imposed pressure, i.e., the viscosity flow activation energy(Eμ) gently increases with the increasing pressure. The viscosity–shear rate data are well fitted to the power law model at low temperature. However, due to the transition of fluid feature at high temperature(Newtonian fluid), the measured viscosity was found to slightly deviate from the fitting data. Combining the evaluated correlations, the viscosity profile of the heavy crude oil in these two deep artesian wells as a function of well depth was predicted using the oilfield producing data.

关键词： Heavy oil Rheological properties Empirical correlation Viscosity profile predication lifting process Artesian well

A review of in situ upgrading technology for heavy crude oil

在线全文

学校读者我要写书评

暂无评论

Petroleum 2021年第2期7卷 117-122页

作者： yibo li Zhiqiang Wang Zhiming Hu Yalong li Wanfen Pu Jinzhou Zhao State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengduChina Petro China Research Institute of Petroleum Exploration&Development LangfangChina c Karamay Hongshan Oilfield Co.Ltd.XinjiangChina

With the growing demand of oil worldwide,heavy oil has increasingly become vital in the world energy ***,further development of heavy oil reservoirs are limited by regular enhanced oil recovery(EOR)*** situ upgrading technology provides potential for the development of heavy oil and bitumen *** study reviews three categories of in situ upgrading methods:solvent-based,in situ combustion(ISC),and ***-based methods,including cyclic solvent injection,vapor extraction,and hybrid processes,have recently received attention and have been progressed in both laboratory and field ***,high solvent costs in relation to the low price of heavy oil have continued to limit the field applications of these ***,which may have the potential to develop particularly harsh reservoirs with extremely viscous crude oil,involves complex reaction mechanisms and consists of three main steps:oxidation,combustion,and gas ***,complex operating conditions and a low success rate have restricted its *** methods,which have demonstrated the potential to refine and upgrade crude oil in a more economic and environmentally friendly way,are often accompanied by conventional thermal EOR methods,such as steam flooding and ISC,and involve a series of hydroprocessing or hydrotreating reactions,such as hydrocracking,hydrodesulfurization,hydrodenitrogenation,hydrodeoxygenation,and ***,the high cost and complexity of the reaction mechanisms have limited their applications.

关键词： In situ upgrading Heavy oil Bitumen In situ combustion Catalytic Solvent

The OsCLV2s-OsCRN1 co-receptor regulates grain shape in rice

在线全文

学校读者我要写书评

暂无评论

Journal of Genetics and Genomics 2024年第7期51卷 691-702页

作者： Xingxing li Meng-en Wu Juncheng Zhang Jingyue Xu Yuanfei Diao yibo li National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research(Wuhan) Huazhong Agricultural UniversityWuhanHubei 430070China Hubei Hongshan Laboratory WuhanHubei 430070China

The highly conserved CLV–WUS negative feedback pathway plays a decisive role in regulating stem cell maintenance in shoot and floral meristems in higher plants,including Arabidopsis,rice,maize,and ***,we find significant natural variations in the OsCLV2c,OsCLV2d,and OsCRN1 loci in a genome-wide association study of grain shape in ***2a,OsCLV2c,OsCLV2d,and OsCRN1 negatively regulate grain length–width ratio and show distinctive geographical distribution,indica–japonica differentiation,and artificial selection ***,OsCLV2a and OsCRN1 interact biochemically and genetically,suggesting that the two components function in a complex to regulate grain shape of ***,the genetic contributions of the haplotypes combining OsCLV2a,OsCLV2c,and OsCRN1 are significantly higher than those of each single gene alone in controlling key yield *** findings identify two groups of receptor-like kinases that may function as distinct co-receptors to control grain size in rice,thereby revealing a previously unrecognized role of the CLV class genes in regulating seed development and proposing a framework to understand the molecular mechanisms of the CLV–WUS pathway in rice and other crops.

关键词： Rice Grain shape OsCLV2s OsCRN1 Natural variations Indica-japonica differentiation

Genetic analysis of GEFs and GDIs in rice reveals the roles of OsGEF5,OsGDI1,and OsGEF3 in the regulation of grain size and plant height

在线全文

学校读者我要写书评

暂无评论

The Crop Journal 2023年第2期11卷 345-360页

作者： Munsif Ali Shad Yixian Wang Hui Zhang Shanshan Zhai Abdullah Shalmani yibo li National Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research(Wuhan) Huazhong Agricultural UniversityWuhan 430070HubeiChina Hubei Hongshan Laboratory Wuhan 430070HubeiChina

Guanine nucleotide exchange factors(GEFs)and guanine nucleotide-dissociation inhibitors(GDIs)regulate small GTPase proteins,which function as molecular switches in various signaling pathways,but their identification and functions in plants are not well *** in-silico analysis and transgenic approaches,respectively,we dissected the evolutionary relationships and functions of all GEF and GDI genes in ***-exon distribution and phylogenetic analyses identified 30 GEF and 10 GDI genes in rice that shared close evolutionary relationships with other ***-specific expression and co-expression analyses revealed that phylogenetically related genes had similar expression *** and GDI genes were highly expressed in panicles,hulls,and ***-expression network analysis identified panicle and stamen-specific modules of co-expressed genes in both *** of these genes in known protein interactomes further identified two and one small G-protein sub-networks.A mutant library of GEF and GDI families was constructed by CRISPR knockout of each gene,and their genotypes and phenotypes were *** changes occurred with the mutation of only three genes(OsGEF5,OsGDI1,and OsGEF3).OsGEF5 and OsGDI1 single mutants exhibited significantly reduced height and longer and thinner grains,whereas OsGEF3 mutants had reduced grain length compared to the wild *** and eGWAS analyses showed that natural variations in the three genes affected gene expression in reproductive tissues that were significantly associated with the phenotypic *** assays demonstrated that GDI1 and GEF3 interacted with grain-size protein GS3,pointing to a role of these genes in the regulation of grain size and plant architecture connected to heterotrimeric G-proteins in rice.

关键词： Rice Guanine nucleotide exchange factors Guanine nucleotide-dissociation inhibitors Mutant library Oriza sativa

OsbZIP60-mediated unfolded protein response regulates grain chalkiness in rice

在线全文

学校读者我要写书评

暂无评论

Journal of Genetics and Genomics 2022年第5期49卷 414-426页

作者： Weiping Yang Pengkun Xu Juncheng Zhang Shuo Zhang Zhenwei li Ke Yang Xinyuan Chang yibo li aNational Key Laboratory of Crop Genetic Improvement and National Centre of Plant Gene Research(Wuhan) Huazhong Agricultural UniversityWuhanHubei 430070China Hubei Hongshan Laboratory WuhanHubei 430070China

Grain chalkiness,an undesirable trait caused by complex factors,has great negative impacts on the quality and economic value of ***,little is known about the regulatory mechanism of grain chalkiness,particularly the effect of endoplasmic reticulum(ER)***,a genome-wide association study(GWAS)reveals that the transcription factor Osb ZIP60 is a vital regulator of rice grain *** analysis demonstrates that knockout of Osb ZIP60 results in extremely high grain chalkiness and aberrant structure of storage ***,the expression of unfolded protein response(UPR)genes,such as OsbZIP50,Os Bi P1,Os Bi P2 and Os Bi P3,is up-regulated in the endosperm cells of osbzip60,and overexpression of all these UPR genes causes various degrees of ***,Osb ZIP60 is found to activate the expression of key genes related to grain chalkiness,such as GPA3,FSE1,FLO7,Chalk5,Os NF-YB1,and Os PK2,whose expression is significantly suppressed in osbzip60 and overexpression lines of Osb ZIP50,Os Bi P1,Os Bi P2,and Os Bi *** study provides novel insights into the function of Osb ZIP60 and the role of the UPR pathway in the formation of grain chalkiness in rice.

关键词： Rice Grain chalkiness GWAS OsbZIP60 OsbZIP50 UPR