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基于网络虚拟展示的农机工业设计研究

农机化研究 2025年第3期47卷 186-191页

作者：尹程黄月芹覃祚萍柳州工学院广西柳州545616 柳州职业技术学院广西柳州545006

农业机械是促进农业发展,加快农业现代化进程的重要保障。随着农业生产模式的转变及社会的快速发展,农业机械的设计不再仅满足于以功能为导向的产品设计与制造,而是更加注重农户的使用体验。为此,以农业机械设计为研究对象,基于CMF对农... 详细信息

农业机械是促进农业发展,加快农业现代化进程的重要保障。随着农业生产模式的转变及社会的快速发展,农业机械的设计不再仅满足于以功能为导向的产品设计与制造,而是更加注重农户的使用体验。为此,以农业机械设计为研究对象,基于CMF对农业机械的外观及色彩要素进行分析,以提高农户使用体验感为主要研究目标对农业机械设计流程进行阐述,最终以虚拟仿真的形式将最终优化设计效果进行展示,形成完善的农业机械优化设计流程。研究结果可以为农业机械产品的设计提供技术指导与理论支撑。

关键词：虚拟仿真 CMF 设计展示

维普期刊数据库博看期刊

Study on performance degradation and failure analysis of machine gun barrel

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Defence Technology（防务技术） 2020年第2期16卷 362-373页

作者： Xiaolong Li Lei Mu Yong Zang qin qin School of Mechanical Engineering University of Science and Technology BeijingBeijing100083China

An increase in the use of the gun barrel will cause wear of the inner wall,which reduces the muzzle velocity and the spin rate of the *** off-bore flight attitude and trajectory of the projectile also change,affecting the shooting power and the *** ballistic data of a high-speed spinning projectile are required to study the performance ***,based on the barrel’s accelerated life test,the whole process of projectile shooting is reproduced using numerical simulation technology,and key information on the ballistic performance change at each shooting stage are *** have shown that in the later stages of barrel shooting,the accuracy of shooting has not decreased ***,it is found that the angle of attack of the projectile increases as the wear of the barrel *** maximum angle of attack reaches 0.106 rad when the number of shots reaches ***,elliptical bullet hole has appeared on the target at this shooting *** combining external ballistic theory with simulation results,the primary reason of this phenomenon is found to be a significant decrease in the muzzle spin rate of the *** the end of the barrel life,the projectile muzzle spin rate is 57.5%lower than that of a barrel without wear.

关键词： Wear of the inner wall Accelerated life test Numerical simulation Ballistic performance End of the barrel life

Tunable ponderomotive squeezing in an optomechanical system with two coupled resonators

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Chinese Physics B 2021年第2期30卷 190-195页

作者： qin Wu School of Biomedical Engineering Guangdong Medical UniversityDongguan 523808China

We investigate properties of the ponderomotive squeezing in an optomechanical system with two coupled resonators,where the tunable two-mode squeezing spectrum can be observed from the output *** is realized that the squeezing orientation can be controlled by the detuning between the left cavity and pump ***,both cavity decay and environment temperature play a positive role in generating better pondermotive squeezing *** squeezing spectra with a wide squeezing frequency range can be obtained by appropriate choice of parameters present in our optomechanical system.

关键词： ponderomotive squeezing light optomechanical system coupled resonators

Characterization of Nanocrystalline Intermetallic Compound NiAl Synthesized by Condensation

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Journal of Materials Science & Technology 1996年第6期12卷 461-463页

作者： qin, Y qin, XY Zhang, LD Institute of Solid State Physics Chinese Academy of Sciences Hefei 230031 China

Nanocrystalline intermetallic compound NiAl was synthesized by evaporating NiAl master alloy in inert-gas followed by in situ compaction, and its structure was studied by means of X-ray diffractometry and transmission electron microscope. Experimental results reveal that the as-synthesized nanocrystalline sample has a mean grain size of less than 10 nm and it is dominantly composed of the cubic structure phase NiAl. However, nanocrystalline Ni3Al as a trace phase mixed in NiAl phase, was also detected by transmission electron microscope observation.

关键词： Intermetallics

Dynamic Uncertain Causality Graph for Knowledge Representation and Reasoning: Discrete DAG Cases

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Journal of Computer Science & Technology 2012年第1期27卷 1-23页

作者： qin Zhang School of Computer Science and Technology Beihang UniversityBeijing 100191China

Developed from the dynamic causality diagram （DCD） model, a new approach for knowledge representation and reasoning named as dynamic uncertain causality graph （DUCG） is presented, which focuses on the compact representation of complex uncertain causalities and efficient probabilistie inference. It is pointed out that the existing models of compact representation and inference in Bayesian Network （BN） is applicable in single-valued cases, but may not be suitable to be applied in multi-valued cases. DUCG overcomes this problem and beyond. The main features of DUCG are： 1） compactly and graphically representing complex conditional probability distributions （CPDs）, regardless of whether the cases are single-valued or multi-valued; 2） able to perform exact reasoning in the case of the incomplete knowledge representation; 3） simplifying the graphical knowledge base conditional on observations before other calculations, so that the scale and complexity of problem can be reduced exponentially; 4） the efficient two-step inference algorithm consisting of （a） logic operation to find all possible hypotheses in concern for given observations and （b） the probability calculation for these hypotheses; and 5） much less relying on the parameter accuracy. An alarm system example is provided to illustrate the DUCG methodology.

关键词： causality uncertainty knowledge representation probabilistic reasoning

Factorization method for inverse obstacle scattering problem in three-dimensional planar acoustic waveguides

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Chinese Physics B 2018年第10期27卷 130-140页

作者： Xue qin School of Mathematical Sciences Peking UniversityBeijing 100871China

In this paper, we consider the inverse scattering problem of reconstructing a bounded obstacle in a three-dimensional planar waveguide from the scattered near-field data measured on a finite cylindrical surface containing the obstacle and corresponding to infinitely many incident point sources also placed on the measurement surface. The obstacle is allowed to be an impenetrable scatterer or a penetrable scatterer. We establish the validity of the factorization method with the nearfield data to characterize the obstacle in the planar waveguide by constructing an outgoing-to-incoming operator which is an integral operator defined on the measurement surface with the kernel given in terms of an infinite series.

关键词： factorization method planar waveguide inverse scattering problem

Molecular testing for acute myeloid leukemia

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Cancer Biology & Medicine 2022年第1期19卷 4-13页

作者： Dahui qin Moffitt Cancer Center TampaFL 33612-9416USA

In the era of personalized medicine,information on molecular change at the gene level is important for patient *** information has been used for disease classification,diagnosis,prognosis,risk stratification,and treatment,which is especially important in cancer patient *** molecular tests exist and can be used to detect the molecular changes at gene *** tests include,but are not limited to,karyotyping,endpoint polymerase chain reaction(PCR),real-time PCR,Sanger sequencing,pyrosequencing,nextgeneration sequencing,and so *** to use the right tests for the right patients at the right time is essential for optimal patient *** review puts together some information on molecular testing for acute myeloid leukemia.

关键词： Molecular test next-generation sequencing acute myeloid leukemia

Gaussianization of peculiar velocities and bulk flow measurement

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Research in Astronomy and Astrophysics 2021年第10期21卷 5-16页

作者： Fei qin Korea Astronomy and Space Science Institute Yuseong-guDaedeok-daero 776Daejeon 34055Korea

The line-of-sight peculiar velocities are good indicators of the gravitational fluctuation of the density *** have been developed to extract cosmological information from the peculiar velocities in order to test cosmological *** techniques include measuring cosmic flow,measuring two-point correlation and power spectrum of the peculiar velocity fields,and reconstructing the density field using peculiar ***,some measurements from these techniques are biased due to the nonGaussianity of the estimated peculiar ***,we rely on the 2MTF survey to explore a power transform that can Gaussianize the estimated peculiar *** find a tight linear relation between the transformation parameters and the measurement errors of log-distance *** show an example for the implementation of Gaussianized peculiar velocities in cosmology,we develop a bulk flow estimator and estimate bulk flow from the Gaussianized peculiar *** use 2MTF mocks to test the algorithm,and we find the algorithm yields unbiased *** also find this technique gives smaller measurement errors compared to other *** Galactic coordinates,at the depth of 30 h^(-1)Mpc,we measure a bulk flow of 332±27 km s^(-1) in the direction(l,b)=(293°±5°,13°±4°).The measurement is consistent with theΛCDM prediction.

关键词： cosmology:large-scale structure of universe

Constraints on the primordial curvature power spectrum by pulsar timing array data:a polynomial parameterization approach

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Communications in Theoretical Physics 2024年第1期76卷 96-104页

作者： qin Fei School of Mathematics and Physics Hubei Polytechnic UniversityHuangshi 435003China

The recent stochastic signal observed jointly by NANOGrav,parkes pulsar timing array,European pulsar timing array,and Chinese pulsar timing array can be accounted for by scalarinduced gravitational waves(SIGWs).The source of the SIGWs is from the primordial curvature perturbations,and the main contribution to the SIGWs is from the peak of the primordial curvature power *** effectively model this peak,we apply the Taylor expansion to parameterize *** the Taylor expansion parameterization,we apply Bayesian methods to constrain the primordial curvature power spectrum based on the NANOGrav 15 year data *** constraint on the primordial curvature power spectrum possesses a degree of generality,as the Taylor expansion can effectively approximate a wide range of function profiles.

关键词： pulsar timing array scalar-induced gravitational waves inflation