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THE BOREL DIRECTIONS OF ALGEBROIDAL FUNCTION AND ITS COEFFICIENT FUNCTIONS 被引量:2
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作者 张少华 张晓梅 孙道椿 《Acta Mathematica Scientia》 SCIE CSCD 2014年第2期241-251,共11页
In this article, the relationship between the Borel direction of algebroidal function and its coefficient functions is studied for the first time. To begin with, several theorems of algebroidal functions in unit disk ... In this article, the relationship between the Borel direction of algebroidal function and its coefficient functions is studied for the first time. To begin with, several theorems of algebroidal functions in unit disk are proved. By these theorems, some interesting conclusions are obtained. 展开更多
关键词 Algebroidal function coefficient function borel direction.
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ON THE BOREL DIRECTION OF K-QUASIMEROMORPHIC MAPPINGS 被引量:3
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作者 杨燕 刘名生 《Acta Mathematica Scientia》 SCIE CSCD 2004年第1期75-82,共8页
For the K-quasimeromorphic mappings, a precise fundamental inequality for the angular domain is established. Prom this, the Borel direction of the K-quasimeromorphic mappings of zero order is derived.
关键词 Quasimeromorphic mapping covering surface borel direction
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BOREL'S DIRECTIONS AND SHARED VALUES 被引量:1
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作者 张庆彩 《Acta Mathematica Scientia》 SCIE CSCD 2013年第2期471-483,共13页
In this article, we study the problems of Borel's directions of meromorphic func- tions concerning shared values and prove that if two meromorphie functions of infinite order share three distinct values, their Borel... In this article, we study the problems of Borel's directions of meromorphic func- tions concerning shared values and prove that if two meromorphie functions of infinite order share three distinct values, their Borel's directions are same. 展开更多
关键词 Meromorphic function borel's direction shared value angular domain
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关于亚纯函数的[p,q]级Borel方向、充满圆、例外值
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作者 刘建明 向旭旭 曾三桂 《贵州师范大学学报(自然科学版)》 CAS 北大核心 2024年第6期67-73,共7页
利用亚纯函数的Nevanlinna理论和亚纯函数[p,q]级的定义,讨论了亚纯函数的[p,q]级充满圆和Borel方向的存在性、Borel方向与充满圆之间的关系,同时考虑了亚纯函数的[p,q]级Borel例外值的相关性质。
关键词 亚纯函数 [p q]级 borel例外值 充满圆 borel方向
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New direction for surgery:Super minimally invasive surgery 被引量:2
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作者 En-Qiang Linghu 《World Journal of Gastroenterology》 SCIE CAS 2024年第12期1676-1679,共4页
The top goal of modern medicine is treating disease without destroying organ structures and making patients as healthy as they were before their sickness.Minimally invasive surgery(MIS)has dominated the surgical realm... The top goal of modern medicine is treating disease without destroying organ structures and making patients as healthy as they were before their sickness.Minimally invasive surgery(MIS)has dominated the surgical realm because of its lesser invasiveness.However,changes in anatomical structures of the body and reconstruction of internal organs or different organs are common after traditional surgery or MIS,decreasing the quality of life of patients post-operation.Thus,I propose a new treatment mode,super MIS(SMIS),which is defined as“curing a disease or lesion which used to be treated by MIS while preserving the integrity of the organs”.In this study,I describe the origin,definition,operative channels,advantages,and future perspectives of SMIS. 展开更多
关键词 Super minimally invasive surgery Minimally invasive surgery Treatment mode Traditional Surgery New direction for surgery
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Estimation of the anisotropy of hydraulic conductivity through 3D fracture networks using the directional geological entropy 被引量:1
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作者 Chuangbing Zhou Zuyang Ye +2 位作者 Chi Yao Xincheng Fan Feng Xiong 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第2期137-148,共12页
With an extension of the geological entropy concept in porous media,the approach called directional entrogram is applied to link hydraulic behavior to the anisotropy of the 3D fracture networks.A metric called directi... With an extension of the geological entropy concept in porous media,the approach called directional entrogram is applied to link hydraulic behavior to the anisotropy of the 3D fracture networks.A metric called directional entropic scale is used to measure the anisotropy of spatial order in different directions.Compared with the traditional connectivity indexes based on the statistics of fracture geometry,the directional entropic scale is capable to quantify the anisotropy of connectivity and hydraulic conductivity in heterogeneous 3D fracture networks.According to the numerical analysis of directional entrogram and fluid flow in a number of the 3D fracture networks,the hydraulic conductivities and entropic scales in different directions both increase with spatial order(i.e.,trace length decreasing and spacing increasing)and are independent of the dip angle.As a result,the nonlinear correlation between the hydraulic conductivities and entropic scales from different directions can be unified as quadratic polynomial function,which can shed light on the anisotropic effect of spatial order and global entropy on the heterogeneous hydraulic behaviors. 展开更多
关键词 3D fracture network Geological entropy directional entropic scale ANISOTROPY Hydraulic conductivity
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亚纯函数的Jackson差分算子和Askey-Wilson差分算子的对数Borel例外值
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作者 王钦 马飞 +1 位作者 王玲 张石梅 《复旦学报(自然科学版)》 CAS CSCD 北大核心 2024年第6期685-694,710,共11页
利用亚纯函数的值分布理论,研究了亚纯函数的Jackson差分算子和Askey-Wilson差分算子的对数Borel例外值的存在性问题,分别刻画了有穷对数级的非常数亚纯函数f与Jackson差分算子D n qf或Askey-Wilson差分算子D AW f的对数Borel例外值之... 利用亚纯函数的值分布理论,研究了亚纯函数的Jackson差分算子和Askey-Wilson差分算子的对数Borel例外值的存在性问题,分别刻画了有穷对数级的非常数亚纯函数f与Jackson差分算子D n qf或Askey-Wilson差分算子D AW f的对数Borel例外值之间的关系。 展开更多
关键词 亚纯函数 对数级 对数borel例外值 Jackson差分算子 Askey-Wilson差分算子
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Preventing brain aging by the artificial enforcement of the unfolded protein response:future directions
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作者 Felipe Cabral-Miranda Claudio Hetz 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期393-394,共2页
As the life expectancy of the world’s population increases,age-related diseases are emerging as one of the greatest problems facing modern society.The onset of dementia and neurodegenerative diseases is strictly depe... As the life expectancy of the world’s population increases,age-related diseases are emerging as one of the greatest problems facing modern society.The onset of dementia and neurodegenerative diseases is strictly dependent on aging as a major risk factor and has a profound impact on various aspects of the lives of individuals and their families. 展开更多
关键词 DISEASES AGING directionS
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Ascertaining the influences of auxiliary qubits on the Einstein–Podolsky–Rosen steering and its directions
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作者 邢玲玲 杨欢 +1 位作者 张刚 孔敏 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期213-221,共9页
Einstein–Podolsky–Rosen(EPR) steering is an example of nontrivial quantum nonlocality and characteristic in the non-classical world.The directivity(or asymmetry) is a fascinating trait of EPR steering,and it is diff... Einstein–Podolsky–Rosen(EPR) steering is an example of nontrivial quantum nonlocality and characteristic in the non-classical world.The directivity(or asymmetry) is a fascinating trait of EPR steering,and it is different from other quantum nonlocalities.Here,we consider the strategy in which two atoms compose a two-qubit X state,and the two atoms are owned by Alice and Bob,respectively.The atom of Alice suffers from a reservoir,and the atom of Bob couples with a bit flip channel.The influences of auxiliary qubits on EPR steering and its directions are revealed by means of the entropy uncertainty relation.The results indicate that EPR steering declines with growing time t when adding fewer auxiliary qubits.The EPR steering behaves as damped oscillation when introducing more auxiliary qubits in the strong coupling regime.In the weak coupling regime,the EPR steering monotonously decreases as t increases when coupling auxiliary qubits.The increases in auxiliary qubits are responsible for the fact that the steerability from Alice to Bob(or from Bob to Alice) can be more effectively revealed.Notably,the introductions of more auxiliary qubits can change the situation that steerability from Alice to Bob is certain to a situation in which steerability from Bob to Alice is certain. 展开更多
关键词 auxiliary qubits EPR steering directionS influence
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Bioinspired directional structures for inhibiting wetting on super-melt-philic surfaces above 1200°C
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作者 Hujun Wang Xiuyuan Zhao +4 位作者 Zhengcan Xie Biao Yang Jing Zheng Kai Yin Zhongrong Zhou 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第4期337-346,共10页
Over the past two decades,superhydrophobic surfaces that are easily created have aroused considerable attention for their superior performances in various applications at room temperature.Nowadays,there is a growing d... Over the past two decades,superhydrophobic surfaces that are easily created have aroused considerable attention for their superior performances in various applications at room temperature.Nowadays,there is a growing demand in special fields for the development of surfaces that can resist wetting by high-temperature molten droplets(>1200°C)using facile design and fabrication strategies.Herein,bioinspired directional structures(BDSs)were prepared on Y2O3-stabilized ZrO2(YSZ)surfaces using femtosecond laser ablation.Benefiting from the anisotropic energy barriers,the BDSs featured with no additional modifiers showed a remarkable increase from 9.2°to 60°in the contact angle of CaO–MgO–Al2O3–SiO2(CMAS)melt and a 70.1%reduction in the spreading area of CMAS at 1250°C,compared with polished super-CMAS-melt-philic YSZ surfaces.Moreover,the BDSs demonstrated exceptional wetting inhibition even at 1400°C,with an increase from 3.3°to 31.3°in contact angle and a 67.9%decrease in spreading area.This work provides valuable insight and a facile preparation strategy for effectively inhibiting the wetting of molten droplets on super-melt-philic surfaces at extremely high temperatures. 展开更多
关键词 directional structures bioinspired design inhibiting wetting super-melt-philic SUPERHYDROPHOBIC
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Study of the pressure transient behavior of directional wells considering the effect of non-uniform flux distribution
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作者 Yan-Zhong Liang Bai-Lu Teng Wan-Jing Luo 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1765-1779,共15页
During the production,the fluid in the vicinity of the directional well enters the wellbore with different rates,leading to non-uniform flux distribution along the directional well.However,in all existing studies,it i... During the production,the fluid in the vicinity of the directional well enters the wellbore with different rates,leading to non-uniform flux distribution along the directional well.However,in all existing studies,it is oversimplified to a uniform flux distribution,which can result in inaccurate results for field applications.Therefore,this paper proposes a semi-analytical model of a directional well based on the assumption of non-uniform flux distribution.Specifically,the direction well is discretized into a carefully chosen series of linear sources,such that the complex well trajectory can be captured and the nonuniform flux distribution along the wellbore can be considered to model the three-dimensional flow behavior.By using the finite difference method,we can obtain the numerical solutions of the transient flow within the wellbore.With the aid of Green's function method,we can obtain the analytical solutions of the transient flow from the matrix to the wellbore.The complete flow behavior of a directional well is perfectly represented by coupling the above two types of transient flow.Subsequently,on the basis of the proposed model,we conduct a comprehensive analysis of the pressure transient behavior of a directional well.The computation results show that the flux variation along the direction well has a significant effect on pressure responses.In addition,the directional well in an infinite reservoir may exhibit the following flow regimes:wellbore afterflow,transition flow,inclined radial flow,elliptical flow,horizontal linear flow,and horizontal radial flow.The horizontal linear flow can be observed only if the formation thickness is much smaller than the well length.Furthermore,a dip region that appears on the pressure derivative curve indicates the three-dimensional flow behavior near the wellbore. 展开更多
关键词 directional well Pressure transient behavior Semi-analytical model Non-uniform flux
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MSD-Net: Pneumonia Classification Model Based on Multi-Scale Directional Feature Enhancement
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作者 Tao Zhou Yujie Guo +3 位作者 Caiyue Peng Yuxia Niu Yunfeng Pan Huiling Lu 《Computers, Materials & Continua》 SCIE EI 2024年第6期4863-4882,共20页
Computer-aided diagnosis of pneumonia based on deep learning is a research hotspot.However,there are some problems that the features of different sizes and different directions are not sufficient when extracting the f... Computer-aided diagnosis of pneumonia based on deep learning is a research hotspot.However,there are some problems that the features of different sizes and different directions are not sufficient when extracting the features in lung X-ray images.A pneumonia classification model based on multi-scale directional feature enhancement MSD-Net is proposed in this paper.The main innovations are as follows:Firstly,the Multi-scale Residual Feature Extraction Module(MRFEM)is designed to effectively extract multi-scale features.The MRFEM uses dilated convolutions with different expansion rates to increase the receptive field and extract multi-scale features effectively.Secondly,the Multi-scale Directional Feature Perception Module(MDFPM)is designed,which uses a three-branch structure of different sizes convolution to transmit direction feature layer by layer,and focuses on the target region to enhance the feature information.Thirdly,the Axial Compression Former Module(ACFM)is designed to perform global calculations to enhance the perception ability of global features in different directions.To verify the effectiveness of the MSD-Net,comparative experiments and ablation experiments are carried out.In the COVID-19 RADIOGRAPHY DATABASE,the Accuracy,Recall,Precision,F1 Score,and Specificity of MSD-Net are 97.76%,95.57%,95.52%,95.52%,and 98.51%,respectively.In the chest X-ray dataset,the Accuracy,Recall,Precision,F1 Score and Specificity of MSD-Net are 97.78%,95.22%,96.49%,95.58%,and 98.11%,respectively.This model improves the accuracy of lung image recognition effectively and provides an important clinical reference to pneumonia Computer-Aided Diagnosis. 展开更多
关键词 PNEUMONIA X-ray image ResNet multi-scale feature direction feature TRANSFORMER
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Effects of cooling rate on microstructure and microhardness of directionally solidified Galvalume alloy
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作者 Ji-peng Li De-gao Qiao +4 位作者 Jian Li Xiao-yang Luo Peng Peng Xian-tao Yan Xu-dong Zhang 《China Foundry》 SCIE EI CAS CSCD 2024年第3期213-220,共8页
The influences of cooling rate on the phase constitution,microstructural length scale,and microhardness of directionally solidified Galvalume(Zn-55Al-1.6Si)alloy were investigated by directional solidification experim... The influences of cooling rate on the phase constitution,microstructural length scale,and microhardness of directionally solidified Galvalume(Zn-55Al-1.6Si)alloy were investigated by directional solidification experiments at different withdrawal speeds(5,10,20,50,100,200,and 400μm·s^(-1)).The results show that the microstructure of directionally solidified Galvalume alloys is composed of primary Al dendrites,Si-rich phase and(Zn-Al-Si)ternary eutectics at the withdrawal speed ranging from 5 to 400μm·s^(-1).As the withdrawal speed increases,the segregation of Si element intensifies,resulting in an increase in the area fraction of the Si-rich phase.In addition,the primary Al dendrites show significant refinement with an increase in the withdrawal speed.The relationship between the primary dendrite arm spacing(λ_(1))and the thermal parameters of solidification is obtained:λ_(1)=127.3V^(-0.31).Moreover,as the withdrawal speed increases from 5 to 400μm·s^(-1),the microhardness of the alloy increases from 90 HV to 151 HV.This is a combined effect of grain refinement and second-phase strengthening. 展开更多
关键词 Galvalume alloy directional solidification microstructure length scale MICROHARDNESS
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Stability assessment of tree ring growth of Pinus armandii Franch in response to climate change based on slope directions at the Lubanling in the Funiu Mountains,China
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作者 Jinkuan Li Jianfeng Peng +4 位作者 Xiaoxu Wei Meng Peng Xuan Li Yameng Liu Jiaxin Li 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期197-208,共12页
Global warming will affect growth strategies and how trees will adapt.To compare the response of tree radial growth to climate warming in different slope directions,samples of Pinus armandii Franch were collected and ... Global warming will affect growth strategies and how trees will adapt.To compare the response of tree radial growth to climate warming in different slope directions,samples of Pinus armandii Franch were collected and treering chronologies developed on northern and western slopes from the Lubanling in the Funiu Mountains.Correlation analyses showed that two chronologies were mainly limited by temperatures in the previous June–August and the combination of temperatures and moisture in the current May–July.The difference of the climate response to slopes was small but not negligible.Radial growth of the LBL01 site on the northern slope was affected by the combined maximum and minimum temperatures,while that of the LBL02 site was affected by maximum temperatures.With regards to moisture,radial growth of the trees on the north slope was influenced by the relative humidity in the current May–July,while on the western slope,it was affected by the relative humidity in the previous June–August,the current May–July and the precipitation in the current May–July.With the change in climate,the effects of the main limiting factors on growth on different slopes were visible to a certain extent,but the differences in response of trees on different slopes gradually decreased,which might be caused by factors such as different slope directions and the change in diurnal temperature range.These results may provide information for forest protection and ecological construction in this region,and a scientific reference for future climate reconstruction. 展开更多
关键词 Tree ring width Lubanling Pinus armandii Franch Slope direction Climate response
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Stability assessment of tree ring growth of Pinus armandii Franch in response to climate change based on slope directions at the Lubanling in the Funiu Mountains,China
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作者 Jinkuan Li Jianfeng Peng +4 位作者 Xiaoxu Wei Meng Peng Xuan Li Yameng Liu Jiaxin Li 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第3期87-98,共12页
Global warming will affect growth strategies and how trees will adapt.To compare the response of tree radial growth to climate warming in different slope directions,samples of Pinus armandii Franch were collected and ... Global warming will affect growth strategies and how trees will adapt.To compare the response of tree radial growth to climate warming in different slope directions,samples of Pinus armandii Franch were collected and tree-ring chronologies developed on northern and western slopes from the Lubanling in the Funiu Mountains.Correlation analyses showed that two chronologies were mainly limited by temperatures in the previous June-August and the com-bination of temperatures and moisture in the current May-July.The difference of the climate response to slopes was small but not negligible.Radial growth of the LBLO1 site on the northern slope was affected by the combined maximum and minimum temperatures,while that of the LBLO2 site was affected by maximum temperatures.With regards to moisture,radial growth of the trees on the north slope was influenced by the relative humidity in the current May-July,while on the western slope,it was affected by the relative humidity in the previous June-August,the current May-July and the precipitation in the current May-July.With the change in climate,the effects of the main limiting factors on growth on different slopes were visible to a certain extent,but the differences in response of trees on different slopes gradually decreased,which might be caused by factors such as different slope directions and the change in diurnal temperature range.These results may provide information for forest protection and ecological construction in this region,and a scientific reference for future climate reconstruction. 展开更多
关键词 Tree ring width Lubanling Pinus armandi Franch Slope direction Climate response
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Numerical simulation on directional solidification and heat treatment processes of turbine blades
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作者 Ye-yuan Hu Ju-huai Ma Qing-yan Xu 《China Foundry》 SCIE EI CAS CSCD 2024年第5期476-490,共15页
Study on turbine blades is crucial due to their critical role in ensuring the efficient and reliable operation of aircraft engines.Nickel-based single crystal superalloys are extensively used in the hot manufacturing ... Study on turbine blades is crucial due to their critical role in ensuring the efficient and reliable operation of aircraft engines.Nickel-based single crystal superalloys are extensively used in the hot manufacturing of turbine blades due to their exceptional high-temperature mechanical properties.The hot manufacturing of single crystal blades involves directional solidification and heat treatment.Experimental manufacturing of these blades is time-consuming,capital-intensive,and often insufficient to meet industrial demands.Numerical simulation techniques have gained widespread acceptance in blade manufacturing research due to their low energy consumption,high efficiency,and rapid turnaround time.This article introduces the modeling and simulation of hot manufacturing in single crystal blades.The discussion outlines the prevalent mathematical models employed in numerical simulations related to blade hot manufacturing.It encapsulates the advancements in research concerning macro to micro-level numerical simulation techniques for directional solidification and heat treatment processes.Furthermore,potential future trajectories for the numerical simulation of single crystal blade hot manufacturing are also discussed. 展开更多
关键词 single crystal blades Ni-based superalloy directional solidification heat treatment numerical simulation
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Dialogue on standards:directions and difficulties of standardization discipline construction
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《China Standardization》 2024年第5期28-49,共22页
To probe into the directions and difficulties of standardization discipline construction in China,China Standardization Press organized a pertinent dialogue on July 10.During the event,Yu Xinli,President of China Asso... To probe into the directions and difficulties of standardization discipline construction in China,China Standardization Press organized a pertinent dialogue on July 10.During the event,Yu Xinli,President of China Association for Standardization,was invited as the moderator.Several standardization experts including Song Mingshun,Mai Lyubo,Qiang Yi,Cao Lili,and Huang Manxue from the China Standardization Expert Committee and renowned universities and research institutes in the country were invited as guests to give their insightful views. 展开更多
关键词 directionS DISCIPLINE standardization
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Dependence of microstructure and mechanical properties on solidification condition of directionally solidified Zn-55Al-1.6Si alloys
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作者 Ji-peng Li De-gao Qiao +5 位作者 Jian Li Peng Peng Kai-di Hu Xian-tao Yan Shu-sen Cheng Yuan-li Xu 《China Foundry》 SCIE EI CAS CSCD 2024年第6期685-692,共8页
In this study,directional solidification was utilized to explore the relationship between microstructure,mechanical properties,and withdrawal speeds of Zn-55Al-1.6Si alloys.In order to assess the characteristics of Zn... In this study,directional solidification was utilized to explore the relationship between microstructure,mechanical properties,and withdrawal speeds of Zn-55Al-1.6Si alloys.In order to assess the characteristics of Zn-55Al-1.6Si alloys,both the microstructure and mechanical properties were thoroughly analyzed.This involved conducting room temperature tensile tests on samples with different withdrawal speeds(5,10,100,200,and 400μm·s^(-1)).The results reveal that both the as-cast alloy and samples after directional solidification are composed of zinc,aluminum,and silicon phases.As the withdrawal speed increases,an evident decrease in the size of the primary dendrites is observed.The results of tensile experiments show that Zn-55Al-1.6Si alloys after directional solidification exhibit brittle fracture characteristics,both the tensile strength and elongation of the alloys increase with withdrawal speed. 展开更多
关键词 Zn-55Al-1.6Si alloy directional solidification microstructure mechanical properties
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Cyclic Beam Direction of Arrival Estimation Method for Ship Propeller Noise
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作者 ZHANG Xiaowei NIE Weihang +1 位作者 XU Ji YAN Yonghong 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第4期883-896,共14页
In underwater acoustic applications,the conventional cyclic direction of arrival algorithm faces challenges,including a low signal-to-noise ratio and high bandwidth when compared with modulated frequencies.In response... In underwater acoustic applications,the conventional cyclic direction of arrival algorithm faces challenges,including a low signal-to-noise ratio and high bandwidth when compared with modulated frequencies.In response to these issues,this paper introduces a novel,robust,and broadband cyclic beamforming algorithm.The proposed method substitutes the conventional cyclic covariance matrix with the variance of the cyclic covariance matrix as its primary feature.Assuming that the same frequency band shares a common steering vector,the new algorithm achieves superior detection performance for targets with specific modulation frequencies while suppressing interference signals and background noise.Experimental results demonstrate a significant enhancement in the directibity index by 81%and 181%when compared with the traditional Capon beamforming algorithm and the traditional extended wideband spectral cyclic MUSIC(EWSCM)algorithm,respectively.Moreover,the proposed algorithm substantially reduces computational complexity to 1/40th of that of the EWSCM algorithm,employing frequency band statistical averaging and covariance matrix variance. 展开更多
关键词 CYCLOSTATIONARITY direction of arrival extended wideband spectral cyclic music cyclic covariance matrix
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Security-Enhanced Directional Modulation Based on Two-Dimensional M-WFRFT
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作者 Zhou Zhuang Luo Junshan +1 位作者 Wang Shilian Xia Guojiang 《China Communications》 SCIE CSCD 2024年第5期229-248,共20页
Directional modulation(DM)is one of the most promising secure communication techniques.However,when the eavesdropper is co-located with the legitimate receiver,the conventional DM has the disadvantages of weak anti-sc... Directional modulation(DM)is one of the most promising secure communication techniques.However,when the eavesdropper is co-located with the legitimate receiver,the conventional DM has the disadvantages of weak anti-scanning capability,anti-deciphering capability,and low secrecy rate.In response to these problems,we propose a twodimensional multi-term weighted fractional Fourier transform aided DM scheme,in which the legitimate receiver and the transmitter use different transform terms and transform orders to encrypt and decrypt the confidential information.In order to further lower the probability of being deciphered by an eavesdropper,we use the subblock partition method to convert the one-dimensional modulated signal vector into a twodimensional signal matrix,increasing the confusion of the useful information.Numerical results demonstrate that the proposed DM scheme not only provides stronger anti-deciphering and anti-scanning capabilities but also improves the secrecy rate performance of the system. 展开更多
关键词 bit error rate directional modulation phased array secrecy rate weighted fractional Fourier transform
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