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Dual information hiding algorithm based on the regularity of 3D mesh model

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Optoelectronics Letters 2022年第9期18卷 559-565页

作者： ren shuai CHENG Huirong FAN Aoxiong School of Information Engineering Chang’an UniversityXi’an 710064China School of Science Xi’an University of Architecture and TechnologyXi’an 710055China

Aiming at the problems of low embedding capacity and inflexibility of embedded information in current three-dimensional(3 D) model information hiding technology, a dual information hiding algorithm based on the mesh characteristics of 3 D model is proposed. The algorithm adopts the strategy of double embedding. By analyzing the regularity of each region of the 3 D model, the feature regions with higher regularity are extracted for embedding secret information. First, in these feature areas, the first secret information is embedded by changing the order of the face list of the object(OBJ) file of the 3 D model. Secondly, filter the triangular meshes according to the regularity, calculate the angle between the plane normals of the two adjacent triangular meshes where the two vertices are adjacent, use the discrete cosine transform to process the angle sequence, and secret information is embedded in the transformation coefficients. The experimental analysis shows that the algorithm can significantly improve the embedding capacity and robustness, and it can effectively resist severe shear attack, geometric attack, and a certain degree of noise attack.

关键词： regularity embedding triangular

Experimental study on 830 MPa grade pipeline steel containing chromium

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International Journal of Minerals,Metallurgy and Materials 2009年第3期16卷 273-277页

作者： Yi ren shuai Zhang Shuang Wang Wen-yue Liu Technical Center Anshan Iron ＆ Steel Co. Ltd. Ar shan 114009 China

The diversity of microstructure and properties of 830 MPa grade pipeline steel containing chromium was investigated by optical microscope and transmission electron microscopy. The main microstructures were multiple configurations, containing lath bainite and granule bainitc. Mechanical properties test results showed that the yield strength and tensile strength improved with increasing chromium content. The toughness and elongation decreased at the same time, so temper process was introduced. Appling proper temper parameters, the values of toughness and elongation were improved dramatically, and the strength decreased slightly.

关键词： chromium high strength pipeline steel thermo-mechanical controlled process

High temperature strain glass in Ti–Au and Ti–Pt based shape memory alloys

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Chinese Physics B 2021年第1期30卷 109-113页

作者： shuai ren Chang Liu Wei-Hua Wang Institute of Physics Chinese Academy of SciencesBeijing 100190China Frontier Institute of Science and Technology State Key Laboratory for Mechanical Behavior of MaterialsXi’an Jiaotong UniversityXi’an 710049China

Strain glass is a frozen short-range strain ordered state found in shape memory alloys recently, which exhibits novel properties around the ideal glass transition temperature T_(0). However, the T_(0) of current strain glass systems is still very low, limiting their potential applications and experimental studies. In this paper, we reported two new strain glass systems with relatively high T_(0). In Ti_(50)Au_(50-x)Cr_(x) alloys, the strain glass appears at x = 25, and exhibits a T_(0) of 251 K, while in Ti_(50)Pt_(50-y)Fey alloys, the strain glass takes place at y = 30, and shows a T_(0) of 272 K. Both of them are comparable with the highest T_(0) value reported so far. Moreover, the phase diagrams of main strain glass systems in Ti-based alloys were summarized. It is found that the influence of the martensitic transformation temperature of the host alloy on the T_(0) of the strain glass is limited. This work may help to design new strain glass systems with higher T_(0) above ambient temperature.

关键词： shape memory alloys martensitic transformation strain glass glass transition temperature

Characterization of Mo–Si–B Nanocomposite Powders Produced Using Mechanical Alloying and Powder Heat Treatment

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Journal of Materials Science & Technology 2015年第10期31卷 995-1000页

作者： Bin Li Guojun Zhang Feng Jiang shuai ren Gang Liu Jun Sun State Key Laboratory for Mechanical Behaviour of Materials Xi'an Jiaotong University School of Materials Science and Engineering Xi'an University of Technology

Mo-Si-B nanocomposite powders with a composition of Mo-12Si-8.5B （in at.%） were processed using mechanical alloying under milling conditions for different milling time and powder-to-ball ratios. The Mo-12Si-8.5B alloy, which consists of α-Mo and intermetallic Mo3Si and T2 phases, was also synthesized by hot-pressed sintering the mechanically alloyed powders under a pressure of 50 MPa at 1600 ℃. The results demonstrated that the sizes and morphologies of the powder particles became gradually refined and uniform by both increasing the milling time and decreasing the powder-to-ball ratio. After 15 h of milling, the powders were completely homogenized at the 1：10 and the 1 ： 15 powder-to-ball weight ratios, and the homogenization was accelerated to rapidly stabilize the milling process because of their high milling energy. Annealing the Mo-Si-B milled powders could promote the growth of the intermetallic Mo3Si and the T2 phases, which formed even after low-temperature annealing at 900 ℃. Increasing the annealing temperature only improved the crystallinity of various phases. When the milled and annealed powders were hot-pressed sintered, the Mo-Si-B alloy exhibited a fine-grained microstructure, where the intermetallics Mo3Si and T2 were distributed in a continuous α-Mo matrix.

关键词： Intermetallics Mechanical alloying Powder metallurgy Microstructure

Application of dynamic recrystallization model in AZ12 magnesium alloy rolling process

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Chinese Journal of Aeronautics 2023年第2期36卷 325-333页

作者： Yanxia NIU Yan SHI Xuelin ZHAO Qichi LE Yixuan WANG shuai ren Na WANG School of Automation Science and Electrical Beihang UniversityBeijing 100191China Department of Musculoskeletal Tumor Senior Department of OrthopedicsThe Fourth Medical Center of PLA General HospitalBeijing 10048China Key Laboratory of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China

To deeply understand the dynamic recrystallization behavior of as-cast AZ12 magnesium alloy in deformation process,the uniaxial hot compression experiments were implemented through systematic isothermal compression *** true strain of thermal compression experiments was set to 50%with temperatures of 200,250,300,350,400℃and the strain rates of 0.001,0.01,0.1,1 s^(-1).The Dynamic Recrystallization(DRX)kinetic model of AZ12 magnesium alloy was established and the accuracy of this model was *** model is used to predict the volume fraction of the sheet obtained by rolling through different rolling passes under the condition of consistent total reduction(50%).And the predicted results are in good agreement with the experimental results.

关键词： AZ12 magnesium alloy Compression DRX model Microstructure Reduction Rolling

Novel assisted cough system based on simulating cough airflow dynamics

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Bio-Design and Manufacturing 2021年第3期4卷 479-489页

作者： shuai ren Jinglong Niu Maolin Cai Liming Hao Yan Shi Weiqing Xu Zujin Luo School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China North Automatic Control Technology Institute Taiyuan 030006China Department of Respiratory and Critical Care Medicine Beijing Engineering Research Center of Respiratory and Critical Care MedicineBeijing Institute of Respiratory MedicineBeijing Chao-Yang HospitalCapital Medical UniversityBeijing 100043China

Cough is a defensive behavior that protects the respiratory system from infection and clears airway *** airflow dynamics have been analyzed by a variety of mathematical and experimental *** this paper,the cough airflow dynamics of 42 subjects were obtained and *** identification model based on piecewise Gauss function for cough airflow dynamics is proposed through the dimensionless method,which could achieve over 90%identification ***,an assisted cough system based on pneumatic flow servo system is *** vacuum situation and feedback control are used to increase the simulated peak cough flow rate,which are important for airway secretion clearance and to avoid airway collapse,*** simulated cough peak flow could reach 5 L/s without the external assistance such as manual pressing,patient cooperation and other ***,the backstepping control is developed to generate a simulated cough airflow that closely mimics the natural cough airflow of *** assisted cough system opens up wide opportunities of practical application in airway secretion clearance for critically ill patients with COVID 2019 and other pulmonary diseases.

关键词： Airflow dynamics Pneumatic system Simulated cough Model identification Airway secretion clearance

Microstructure and improved mechanical properties of ultrafine-grained Mo-12Si-8.5B（at.%） alloys with addition of ZrB2

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Progress in Natural Science:Materials International 2018年第3期28卷 371-377页

作者： Juan Wang shuai ren Rui Li Xuan Chen Bin Li Tao Wang Guojun Zhang School of Materials Science and Engineering Xi'an University of Technology Northwest Institute for Non-ferrous Metal Research

Multi-hierarchical Mo-12Si-8.5B-x Zr B;（x=0,0.5,1.0,1.5,2.5 wt%）alloys consisting of three ultrafine-grained（UFG,0.47–0.81μm）phases of Mo;Si B;（T2）,Mo;Si and Mo solid solution（α-Mo）were prepared by mechanical alloying following hot *** observations showed that the intermetallic phases（Mo;Si and T2）distributed dispersedly in the continuousα-Mo matrix associated with the homogeneously embedded nanoscaled particles（10–225 nm）in the grain interiors and at the grain *** Mo-12Si-8.5B-x Zr B;alloys exhibited monotonically increasing compressive strength to 3.13 GPa with increasing content of Zr B;,and the fracture toughness increased about 27%and reached at 11.5 MPa m;at 1.0 wt%Zr B;,rendering the Mo-12Si-8.5B-1.0 wt%Zr B;alloy possessing the best combined mechanical properties of high strength and high *** underlying reason for the superior mechanical properties of the Mo-12Si-8.5B-x Zr B;alloys is that the dispersedly distributed nanosized particles in the UFG multi-phased-matrix can not only effectively block the dislocation motion to increase the strength but also store the dislocations to increase the strain hardening ability during mechanical deformation.

关键词： Mo-12Si-8.5B alloy ZrB2 addition Microstructure Mechanical properties

Distributed trusted demand response bidding mechanism empowered by blockchain

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Intelligent and Converged Networks 2024年第3期5卷 181-191页

作者： Lei Wang Tong Li Chao Yang Jiang Chen Yang Liu shuai ren State Grid Liaoning Electric Power Co. Ltd.Shenyang 110000China Liaoning Electric Power Research Institute of State Grid Corporation of China Shenyang 110000China

In the demand response process involving multi-agent participation,multiple parties’interests are involved and response execution status supervision is *** centralized demand response systems lack trust *** the same time,traditional centralized cloud management can no longer support massive terminal services,resulting in delays in demand response *** build a distributed trusted demand response architecture based on blockchain,illustrating the information interaction process in the demand bidding process and container-based edge-side heterogeneous resource *** also propose a demand bidding algorithm that takes into account both the day-ahead market and the intraday market,aiming to maximize the aggregator’s *** addition,a virtual resource management algorithm to support demand response tasks is also proposed to optimize computing resource allocation and meet business latency *** results demonstrate that compared with only cloud computing or edge computing,the solution we proposed can reduce response delay by more than 39% for the sample *** cost is saved by about 10.25%during container scheduling.

关键词： demand response blockchain edge and cloud computing demand bidding virtual resource management

A self-powered solar-blind UV-enhanced Bi_(2)Se_(3)/a-Ga_(2)O_(3)/p-Si heterojunction photodetector for full spectral photoresponse and imaging

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Nano Research 2024年第4期17卷 2960-2970页

作者： Yajie Han Shujie Jiao Jiangcheng Jing Lei Chen Ping Rong shuai ren Dongbo Wang Shiyong Gao Jinzhong Wang School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Self-powered full-spectrum photodetectors(PDs)offer numerous advantages,such as broad application fields,high precision,efficiency,and multi-functionality,which represent a highly promising and potentially valuable class of detectors for future ***,insensitive response to solar-blind ultraviolet(UV)and complex and expensive preparation processes greatly limit their performance and practical *** this study,a self-powered full-spectrum Bi_(2)Se_(3)/a-Ga_(2)O_(3)/p-Si heterojunction PD with high sensitivity for solar-blind UV band prepared by a simple and low-cost two-step synthesis method is *** results reveal that the developed PD has an excellent performance,such as high sensitivity from 200 to 850 nm,and a responsivity of 1.38 mA/W as well as a detectivity of 3.22×10^(10) Jones under 254 nm light at zero ***,the unencapsulated device displays exceptional stability and imaging *** is expected that Bi_(2)Se_(3)/a-Ga_(2)O_(3)/p-Si heterojunction PD with a simple and low-cost synthesis method has great potential for self-powered full-spectrum photodetectors.

关键词： Bi_(2)Se_(3)/a-Ga_(2)O_(3)/p-Si self-powered photodetector full spectral photoresponse imaging