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Chinese Journal of Chemical Engineering 2020年第12期28卷 3152-3158页

作者： qi Zhang Zhaoliang cui Weixing Li State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 210009China national Engineering Research Center for Special Separation Membrane Nanjing Tech UniversityNanjing 210009China

In order to improve the water permeability of poly(vinylidene fluoride)(PVDF)ultrafiltration(UF)membranes with low molecular weight cut-off(MWCO),polydopamine(PDA)was employed in the membrane preparation *** to itsmerits of material-independent adhesion,PDAwas coated on inorganic particles or added in coagulation bath to tailor the final membrane structure and *** introduction of PDA broke through the permeability/selectivity trade-off of the PVDF *** adding the PDA coated titaniumdioxide(PDA/TiO2)nanoparticles,water flux increased by 287% while MWCO kept similar with the pristine PVDF *** and Kinetics of the PVDF/additives/non-solvent were analyzed and shown that nanoparticles reduced the thermodynamic stability and increased the phase separation speed,and the speed can be adjusted using different ***,X-ray diffraction(XRD)test indicated that PVDF crystalline form changed fromαphase to β phase after adding different ***/selectivity trade-offwas broken through by DA addition in coagulation *** with the original PVDF membrane,when the DA concentration of the coagulation bath was 2.0 g·L^−1,water flux increased by 312%,and MWCO of the PVDF membrane ranged in 10,000 to 20,000 Da as well as contact angle decreased from 81.4°to 45°.

关键词： Poly(vinylidene fluoride)membrane Polydopamine Permeability/selectivity trade-off

Formulation of grain growth diagram in simulated weld HAZ of Ti-microalloyed steel

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Acta Metallurgica Sinica(English Letters) 2009年第4期22卷 308-312页

作者： Chibin GUI qi CHEn Kun.cui Department of naval Architecture and Ocean Engineering School of Naval Architecture and Power Engineering Navy University of Engineering Wuhan 430033 China

In this paper, the response of Tin particles to welding thermal cycle and the kinetic behavior of the grain growth in weld heat-affected zone of the Ti-microalloyed steel have been studied by using the simulation technology. Based on the theory of the Tin particle dissolution and coarsening kinetic models in weld thermal cycle and some metallographic data from thermal simulated samples, the grain growth diagram of Ti-microalloyed steel is presented. The experimental data from thermal simulated weld samples agreed well with the value of the diagram predicted.

关键词： Ti-microalloyed steel Grain growth in weld HAZ Simulation technology

A constrained particle dynamics for continuum-particle hybrid method in micro- and nano-fluidics

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Acta Mechanica Sinica 2006年第6期22卷 503-508页

作者： Jia cui Guo Wei He Dewei qi LnM Institute of Mechanics Chinese Academy of SciencesBeijing 100080 China Department of Paper and Chemical Engineering Western Michigan University Kalamazoo MI 49008 USA

A hybrid method of continuum and particle dynamics is developed for micro- and nano-fluidics, where fluids are described by a molecular dynamics （MD） in one domain and by the navier-Stokes （nS） equations in another domain. In order to ensure the continuity of momentum flux, the continuum and molecular dynamics in the overlap domain are coupled through a constrained particle dynamics. The constrained particle dynamics is constructed with a virtual damping force and a virtual added mass force. The sudden-start Couette flows with either non-slip or slip boundary condition are used to test the hybrid method. It is shown that the results obtained are quantitatively in agreement with the analytical solutions under the non-slip boundary conditions and the full MD simulations under the slip bound- ary conditions.

关键词： Hybrid method Molecular dynamicsimulation navier-Stokes equation Microfluidics

High precision phase-domain radial velocity estimation for wideband radar systems

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Journal of Systems Engineering and Electronics 2020年第3期31卷 520-526页

作者： qi Wei cui Zijian YAO Huisheng DEnG Zhenmiao Beijing Institute of Tracking and Telecommunications Technology Beijing 100094China School of Information Science and Technology Xiamen UniversityXiamen 210016China

Radial velocity estimation used in wide-band radar systems is *** analyzing the signal of cross-correlation output of adjacent echoes,it is found that the frequency and phase of the cross-correlation output are related to the target’s radial *** the precision of the phase estimation is higher than that of the frequency,a phase-based velocity estimator is ***,the ambiguity problem exists in the phase estimators,and thus the estimation of the cross-correlation of adjacent echoes(CCAE)is used to calculate the ambiguity *** root-mean-square-error(RMSE)of the proposed estimator is *** results show that the performance of the proposed method is better than that of the frequency-based estimator.

关键词： radial velocity estimation ambiguity wideband radar system

THE DELAYED BARBOUR＇S MODEL FOR SCHISTOSOMIASIS

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International Journal of Biomathematics 2012年第2期5卷 117-137页

作者： LOnGXInG qi JInG-An.cui School of Mathematical Sciences Anhui University Hefei 230601P.R.China College of Science Beijing University of Civil Engineering and Architecture Beijing 100044 P.R.China

The transmission of schistosomiasis involves latent periods of infected hosts. In this paper, considering the latent periods of infected human, infected bovines and infected snails, we propose a delayed Barbour＇s model with two definitive hosts and define basic reproductive number. The stability of equilibria for the systems with and without time delays are both investigated. To study the impact of the latent periods on the transmission of schistosomiasis, some sensitivity analysis of the basic reproductive number on the three time delays are carried out. It is shown that the basic reproductive number decreases as the three time delays increase. Furthermore, the impact of the latent periods of infected snails on the system is stronger than that of the latent periods of infected human and infected bovines. Thus, to reduce the prevalence of schistosomiasis infection, prolonging the latent periods of infected snails by some measures could achieve better results than prolonging the latent periods of infected definitive hosts.

关键词： Barbour's two-definitive-host model schistosomiasis basic reproductivenumber three time delays.

Speech Encryption with Fractional Watermark

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Computers, Materials & Continua 2022年第10期73卷 1817-1825页

作者： Yan Sun Cun Zhu qi cui Key Laboratory of Artificial Intelligence Application Technology State Ethnic Affairs Commission Qinghai Minzu UniversityXining810007QinghaiChina School of Computer of qinghai normal University Xining810003QinghaiChina The Department of Electrical and Computer Engineering University of WindsorWindsorN9B 3P4Canada

Research on the feature of speech and image signals are carried out from two perspectives,the time domain and the frequency *** speech and image signals are a non-stationary signal,so FT is not used for the non-stationary characteristics of the *** short-term stable speech is obtained by windowing and framing the subsequent processing of the signal is completed by the Discrete Fourier Transform(DFT).The Fast Discrete Fourier Transform is a commonly used analysis method for speech and image signal processing in frequency *** has the problem of adjusting window size to a for desired *** the Fractional Fourier Transform can have both time domain and frequency domain processing *** paper performs global processing speech encryption by combining speech with image of Fractional Fourier *** speech signal is embedded watermark image that is processed by fractional transformation,and the embedded watermark has the effect of rotation and superposition,which improves the security of the *** paper results show that the proposed speech encryption method has a higher security level by Fractional Fourier *** technology is easy to extend to practical applications.

关键词： Fractional Fourier Transform watermark speech signal processing image processing

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电动拖拉机复合式振动馈能系统设计及试验

农机化研究 2025年第4期47卷 230-235页

作者：王旭东王琪王威陈雨崔永杰西北农林科技大学机械与电子工程学院陕西杨凌712100 陕西省农业信息感知与智能服务重点实验室陕西杨凌712100 农业农村部农业物联网重点实验室陕西杨凌712100

为了回收和利用电动拖拉机行驶过程中产生的振动能量,基于浮动电池组提出了一种压电-机械电磁复合式振动馈能装置;然后,根据装置的电压输出特性构建了包含整流滤波、LM317稳压、超级电容储能和Boost升压模块的电能提取电路,以满足蓄电... 详细信息

为了回收和利用电动拖拉机行驶过程中产生的振动能量,基于浮动电池组提出了一种压电-机械电磁复合式振动馈能装置;然后,根据装置的电压输出特性构建了包含整流滤波、LM317稳压、超级电容储能和Boost升压模块的电能提取电路,以满足蓄电池充电需求;最后,进行了复合式振动馈能系统的实车试验。结果表明:电动拖拉机车速为4 km/h时,馈能装置的最大输出电压为34.80 V,平均输出功率为0.57 W;经过等效计算,由复合式馈能系统回收的电能可使电动拖拉机的续航时间延长0.784 7 h。研究结果可为我国电动拖拉机的电能补给和工作时间延长提供理论与技术支撑。

关键词：电动拖拉机振动能量回收复合式振动馈能装置电能提取电路

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电动拖拉机犁耕机组阻力自适应作业控制研究

农机化研究 2025年第4期47卷 224-229页

作者：王琪王旭东王威张硕崔永杰西北农林科技大学机械与电子工程学院陕西杨凌712100 陕西省农业信息感知与智能服务重点实验室陕西杨凌712100 农业农村部农业物联网重点实验室陕西杨凌712100

犁耕质量和效率对粮食高产至关重要,而以往基于悬挂高度调整以适应阻力变化来控制犁耕机组耕作效率存在耕深不均匀的问题。为此,以重心可调电动拖拉机犁耕机组为对象,提出了调定耕深下考虑速度和滑转率的阻力自适应作业控制方法。首先,... 详细信息

犁耕质量和效率对粮食高产至关重要,而以往基于悬挂高度调整以适应阻力变化来控制犁耕机组耕作效率存在耕深不均匀的问题。为此,以重心可调电动拖拉机犁耕机组为对象,提出了调定耕深下考虑速度和滑转率的阻力自适应作业控制方法。首先,建立了机组动力学模型并分析了阻力变化下机组的动态特性;然后,采用模糊神经网络控制算法调节驱动电机转矩和电池组位移,使牵引附着性能自动适应阻力变化,以实现速度和滑转率的联合控制;最后,进行了实车测试平台搭建和犁耕试验。结果表明:耕速最大偏差仅为0.48 km/h,相比于控制前滑转率降低了21.42%,牵引效率提高了7.76%。在恒定耕深下机组作业稳定性和效率得以提高,为电动拖拉机的自动化和智能化精准作业提供了技术支持。

关键词：电动拖拉机犁耕作业自适应控制牵引效率

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A Survey of Image Information Hiding Algorithms Based on Deep Learning

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Computer Modeling in Engineering & Sciences 2018年第12期117卷 425-454页

作者： Ruohan Meng qi cui Chengsheng Yuan School of Computer and Software Nanjing University of Information Science and TechnologyNing Liu RoadNo.219Nanjing210044China Jiangsu Engineering Centre of network Monitoring Ning Liu RoadNo.219Nanjing210044China Department of Electrical and computer Engineering University of Windsor401 Sunset AvenueWindsorONN9B 374Canada.

With the development of data science and technology,information security has been further *** order to solve privacy problems such as personal privacy being peeped and copyright being infringed,information hiding algorithms has been *** information hiding is to make use of the redundancy of the cover image to hide secret information in *** that the stego image cannot be distinguished from the cover image,and sending secret information to receiver through the transmission of the stego *** present,the model based on deep learning is also widely applied to the field of information *** paper makes an overall conclusion on image information hiding based on deep *** is divided into four parts of steganography algorithms,watermarking embedding algorithms,coverless information hiding algorithms and steganalysis algorithms based on deep *** these four aspects,the state-of-the-art information hiding technologies based on deep learning are illustrated and analyzed.

关键词： Steganography deep learning steganalysis watermarking coverless information hiding.

Identifying Materials of Photographic Images and Photorealistic Computer Generated Graphics Based on Deep Cnns

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Computers, Materials & Continua 2018年第5期55卷 229-241页

作者： qi cui Suzanne McIntosh Huiyu Sun School of Computer and Software Nanjing University of Information Science and TechnologyNing Liu RoadNo.219Nanjing210044China Jiangsu Engineering Centre of network Monitoring Ning Liu RoadNo.219Nanjing210044China Computer Science Department New York UniversityNew YorkNY 10012USA

Currently,some photorealistic computer graphics are very similar to photographic *** computer generated graphics can be forged as photographic images,causing serious security *** aim of this work is to use a deep neural network to detect photographic images(PI)versus computer generated graphics(CG).In existing approaches,image feature classification is computationally intensive and fails to achieve realtime *** paper presents an effective approach to automatically identify PI and CG based on deep convolutional neural networks(DCnns).Compared with some existing methods,the proposed method achieves real-time forensic tasks by deepening the network *** results show that this approach can effectively identify PI and CG with average detection accuracy of 98%.

关键词： Image identification Cnn Dnn DCnns computer generated graphics