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Cure of a New Type Composite on Noise Control and Effect of Filler Modification

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Journal of Materials Science & Technology 2003年第z1期19卷 135-136页

作者： Jun cai Fei XU Weimin cai School of Municipal and Environment Englineering Harbin Institute of Technology Harbin150001china School of Environment Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China School of Environment Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China

A new type composite of high efficiency sound attenuation was cured. The superfine tungsten powder, plasticizerand stabilizer are added into the PVC resin and blended in the mixing chamber of a HAAKE rheometer. The effect ofthe filler modification is considered in the composite cure. The properties of modified composite and unmodified oneare studied by SEM morphology viewing, acoustic and mechanical measurement. The test results indicate that thereason of the better soundproof and mechanical properties is the particle uniform dispersion and stronger adhesion.

关键词： Composite, Filler modification, Soundproof property, Mechanical property

数智时代出版伦理规范的价值冲突、融合与重塑

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湖北科技学院学报 2025年第1期45卷 66-72页

作者：蔡绍硕湖南师范大学新闻与传播学院湖南长沙410081

在社会伦理与出版伦理共同规制而形成的复杂关系网中,我国的出版伦理规范面临着出版业职业价值、商业价值、社会价值与出版物价值之间交错重叠的对立冲突。究其原因在于数智时代下,现有规范体系内容制定上结构不清晰,执行机制上不完备... 详细信息

在社会伦理与出版伦理共同规制而形成的复杂关系网中,我国的出版伦理规范面临着出版业职业价值、商业价值、社会价值与出版物价值之间交错重叠的对立冲突。究其原因在于数智时代下,现有规范体系内容制定上结构不清晰,执行机制上不完备以及在价值评判标准上无法实现多维冲突的价值融合。因此增强规范体系的规制效用,需要重塑出版机构、监管组织与读者公众话语间的一种新型共生关系:监管组织引导出版业制定结构清晰、实用性强的行业自律规范;出版机构健全职业自律机制,针对具体的失范问题制定便于价值评判的细则规定;读者公众积极参与,促进社会团体对出版行业的监督。

关键词：出版伦理规范体系价值冲突价值融合

Shor's algorithm does not factor large integers in the presence of noise

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Science China(Information Sciences) 2024年第7期67卷 305-320页

作者： Jin-Yi cai College of Letters and Science University of Wisconsin

We consider Shor's quantum factoring algorithm in the setting of noisy quantum gates. Under a generic model of random noise for(controlled) rotation gates, we prove that the algorithm does not factor integers of the form pq when the noise exceeds a vanishingly small level in terms of n—the number of bits of the integer to be factored, where p and q are from a well-defined set of primes of positive density. We further prove that with probability 1-o(1) over random prime pairs(p, q), Shor's factoring algorithm does not factor numbers of the form pq, with the same level of random noise present.

关键词： random noise Shor’s algorithm rotation gates quantum computing prime factorization

Lattice Boltzmann simulation of flows in bifurcate channel at rotating inflow boundary conditions and resulted different outflow fluxes

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Acta Mechanica Sinica 2011年第4期27卷 510-518页

作者： Qing-Dong cai Department of Mechanics and Aerospace Engineering College of Engineering Peking University 100871 Beijing

The Lattice Boltzmann method （LBM） is used to simulate the flow field in a bifurcate channel which is a simplified model of the draft tube of hydraulic turbine machine. According to the simulation results, some qualitative conclusions can be deduced. The reason of uneven flux in different branches of draft tube is given. Not only the vortex rope itself, but also the attenuation of the rotation strength is important in bringing on the uneven flux. The later leads to adverse pressure gradient, and changes the velocity profile. If the outlet contains more than one exit, the one that contains the vortex rope will lose flux because of this adverse pressure gradient. Several possible methods can be used to minimize the adverse pressure gradient domain in order to improve the efficiency of turbine machine.

关键词： Lattice Boltzmann method - Hydraulic turbinemachine Draft tube Vortex rope

Rock support in strainburst-prone ground

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International Journal of Mining Science and Technology 2019年第4期29卷 529-534页

作者： M.cai MIRARCO Laurentian University Bharti School of Engineering Laurentian University Key Laboratory of Ministry of Education for Safe Mining of Deep Metal Mines Northeastern University

Strainburst is the most frequently encountered type of rockburst in underground *** occurs when the stress near the excavation boundary reaches the peak strength of the rock mass causing it to fail suddenly and *** mitigate strainburst damage risk,effective rock support is *** strainburst-prone grounds,it is critical to have rock support components to fulfill the role of rock reinforcement first to prevent rock *** the other hand,well-retained and reinforced rock masses may be excessively deformed and fail *** such a case,yielding elements are needed in the rock support system to absorb the excess strain energy released due to rock *** conventional method to support strainburst-prone grounds is to install rock reinforcement system using rebar and mesh first and then install yielding support system using dynamic rockbolts at a later *** two-stage rock support installation process is not effective because it can adversely impact mine production *** paper presents a new,patented dynamic rockbolt,which is called superbolt and is developed for rock support in burst-prone *** testing confirmed that the superbolt has superb capacity to achieve the goal of reinforcing and holding rock *** superbolt is characterized by high dynamic energy absorption capacity,consistent performance,and the ability to withstand repeated dynamic *** new rockbolt can be used in a one-pass rock support system to facilitate rapid drift development in underground mines and increase mine safety and productivity.

关键词： Rockburst Strainburst Rock support Dynamic failure Energy Capacity

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基于不平衡数据的网络流量异常检测方法研究

电子设计工程 2025年第1期33卷 46-50页

作者：蔡登江中国海洋石油集团有限公司信息技术中心北京100010

为有效解决不平衡数据影响的问题,确保面对大规模网络流量数据异常检测的实时性,提出了基于不平衡数据的网络流量异常检测方法。通过优化SMOTE(合成少数类过采样)算法对含不平衡数据的网络流量数据进行平衡处理,将得到的数据集通过核主... 详细信息

为有效解决不平衡数据影响的问题,确保面对大规模网络流量数据异常检测的实时性,提出了基于不平衡数据的网络流量异常检测方法。通过优化SMOTE(合成少数类过采样)算法对含不平衡数据的网络流量数据进行平衡处理,将得到的数据集通过核主成分分析方法实现特征提取后,输入到卷积神经网络中。通过卷积和池化过程进一步实现网络流量数据深度特征提取,依据Softmax分类层对网络流量特征进行分类,利用训练好的卷积神经网络预测模型实现不平衡数据的网络流量异常检测。通过实验验证,该方法展现出了良好的效率和稳定性。在迭代次数为40次时,实现最佳不平衡数据处理结果,能够对异常数据进行精准识别。

关键词：不平衡数据网络流量异常检测优化SMOTE算法核主成分分析卷积神经网络 Softmax分类

A novel unsupervised deep learning method for the generalization of urban form

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Geo-Spatial Information Science 2022年第4期25卷 568-587页

作者： Jihong cai Yimin Chen School of Geography and Planning Sun Yat-sen UniversityGuangzhouChina

Accurate delineation of urban form is essential to understand the impacts that urbanization has on the environment and regional *** supervised classification of urban form requires a rigidly defined scheme and high-quality sample data with class *** to the complexity of urban systems,it is challenging to consistently define urban form types and collect metadata to describe ***,in this study,we propose a novel unsupervised deep learning method for urban form delineation while avoiding the limitations of conventional super-vised urban form classification *** novelty of the proposed method is the Multiscale Residual Convolutional Autoencoder(MRCAE),which can learn the latent representation of differ-ent urban form *** vectors can be further used to generalize urban form types by using Self-Organizing Map(SOM)and the Gaussian Mixture Model(GMM).The proposed method is applied in the metropolitan area of Guangzhou-Foshan,*** MRCAE model along with SOM and GMM is used to generalize the urban form types from satellite *** physical and functional properties of each urban form type are also analyzed using several auxiliary datasets,including building footprints,Points-of-Interests(POIs)and Tencent User Density(TUD)*** results reveal that the urban form map generated based on the MRCAE can explain 55%of the building height distribution and 55%of the building area distribution,which are 2.1%and 3.3%higher than those derived from the conventional convolutional *** the information of urban form is essential to urban climate models,the results presented in this study can become a basis to refine the quantification of urban climate parameters,thereby introducing the urban heterogeneity to help understand the climate response of future urbanization.

关键词： Convolutional autoencoder Self-Organizing Map(SOM) Gaussian Mixture Model(GMM) urban form clustering

Spatial phase structure and oxidation process of Al-W alloy powder with high sphericity

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Journal of Materials Science & Technology 2022年第19期114卷 62-72页

作者： Aobo Hu Shuizhou cai State Key Laboratory of Material Processing and Die&Mould Technology The School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

In this study,Al-30W(wt.%)alloy powder was prepared by Aluminothermic reduction and hightemperature gas *** then studied the phase composition,surface morphology,spatial phase structure,and thermal oxidation process using XRD,SEM/EDS,TEM,DSC,and DTA/TG *** results showed that the Al-30W alloy powder exhibited high sphericity,and the interior presented a special spatial phase structure in which the Al/W amorphous alloy phase and the metastable Al/W intermetallic compound phase were distributed in the pure Al *** the Al-30W alloy powder was stabilized in a vacuum tube furnace,the spatial phase structure of the alloy powder changed,and a small amount of pure Al was embedded in the Al_(12)W *** resulting Al-30W alloy powder products,treated in air at different temperatures,were collected in situ and *** results presented that with an increase in temperature,the types and morphologies of the Al/W intermetallic compounds in the Al-30W alloy powder ***,the Al-30W alloy powder began to undergo intense oxidation reactions at about 900℃,accompanied by a concentrated energy release and rapid weight *** volatilization of WO_(3)produced in the oxidation process promoted the complete oxidation of the Al-30W alloy powder,and the Al-30W alloy powder was completely oxidized at 1300℃.At this stage,all W atoms were transformed into gaseous WO_(3),and only a large number of small Al_(2)O_(3)fragments remained in the oxidation ***,the Al-30W alloy powder exhibited excellent thermal reactivity and oxidation integrity,and may offer excellent application prospects in the field of energetic materials.

关键词： Aluminothermic reduction High-temperature gas atomization Al/W amorphous alloy phase Metastable Al/W intermetallic compound phase Thermal oxidation process

Parameter identification and blanking simulations of DP1000 and Al6082-T6 using Lemaitre damage model

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Advances in Manufacturing 2021年第3期9卷 457-472页

作者： Sheng cai Lin Chen Department of Vehicle Engineering College of EngineeringChina Agricultural UniversityBeijing100083People’s Republic of China CW Bearing GmbH 22113HamburgGermany

This work provides numerical and experimental investigations of blanking process,where the shear-enhanced Lemaitre’s damage model is fully characterized and successfully applied in blanking process to predict the cutting force and cutting edge geometry under different blanking process *** high strength steel DP1000 and an aluminum alloy Al6082-T6 are selected for series of *** obtain the damage parameters in Lemaitre’s damage model the flat rectangular notched specimens tensile test was conducted and the inverse parameter identification procedure was *** characterizing the crack closure parameter h in the shear enhanced Lemaitre’s damage model,an in-plane torsion test with novel specimen design was *** finite element model(FEM)of this test was established with the minimum mesh size of 0.01 mm which was consistent with the minimum mesh size in the shear zone of the FEM for blanking process *** longitudinal strain distributions of four kinds of initial notch radius or central-hole specimen were measured and compared with simulation results to validate the FEMs for these four *** analysis of blanking of a circular work piece also was performed under three *** effects of blanking conditions on sheared part morphology were *** triaxiality distribution of the blank sheet was revealed taking advantage of the successfully established *** availability of the testing method and the determination method of the parameters was investigated.

关键词： Blanking Lemaitre damage model Stress triaxiality Finite element model(FEM)