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A Wrapping Encryption Based on Double Randomness Mechanism

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Computers, Materials & Continua 2023年第10期77卷 1143-1164页

作者： Yi-Li huang Fang-Yie Leu Ruey-Kai Sheu Jung-Chun Liu Chi-Jan huang Department of Computer Science Tunghai UniversityTaichung40764Taiwan Emergency Response Management Center Ming Chung UniversityTaipei11103Taiwan General Education Center Ming Chuan UniversityTaipei11103Taiwan

Currently,data security mainly relies on password(PW)or system channel key(SKCH)to encrypt data before they are sent,no matter whether in broadband networks,the 5th generation(5G)mobile communications,satellite communications,and so *** these environments,a fixed password or channel key(e.g.,PW/SKCH)is often adopted to encrypt different data,resulting in security risks since thisPW/SKCH may be solved after hackers collect a huge amount of encrypted ***,the most popularly used security mechanism Advanced Encryption Standard(AES)has its own problems,e.g.,several rounds have been *** the other hand,if data protected by the same PW/SKCH at different time points can derive different data encryption parameters,the system’s security level will be then greatly ***,in this study,a security scheme,named Wrapping Encryption Based on Double Randomness Mechanism(WEBDR),is proposed by integrating a password key(or a system channel key)and an Initialization Vector(IV)to generate an Initial Encryption Key(IEK).Also,an Accumulated Shifting Substitution(ASS)function and a three-dimensional encryption method are adopted to produce a set of *** randomness encryption mechanisms are *** first generates system sub-keys and calculates the length of the first pseudo-random numbers by employing IEK for providing subsequent encryption/*** second produces a random encryption key and a sequence of internal feedback codes and computes the length of the second pseudo-random numbers for encrypting delivered messages.A wrapped mechanism is further utilized to pack a ciphertext file so that a wrapped ciphertext file,rather than the ciphertext,will be produced and then transmitted to its *** findings are as *** theoretic analyses and simulations demonstrate that the security of the WEBDR in cloud communication has achieved its practical ***,AES requires 176 times exclusive OR(XOR)operations for both encryption an

关键词： Initial encryption key accumulated shifting substitution three-dimensional operation wrapped ciphertext file

On comparison of modified ADRCs for nonlinear uncertain systems with time delay

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Science China(Information Sciences) 2018年第7期61卷 212-226页

作者： Sen CHEN Wenchao XUE Sheng ZHONG Yi huang Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences

To tackle systems with both uncertainties and time delays, several modified active disturbance rejection control(ADRC) methods, including delayed designed ADRC(DD-ADRC), polynomial based predictive ADRC(PP-ADRC), Smith predictor based ADRC(SP-ADRC) and predictor observer based ADRC(PO-ADRC), have been proposed in the past years. This paper is aimed at rigorously investigating the performance of these modified ADRCs, such that the improvements of each method can be *** capability to tackle time delay, the necessity of stable open loop and the performance of rejecting uncertainties for these methods are fully studied and compared. It is proven that large time delay cannot be tolerated for the stability of the closed-loop systems based on DD-ADRC and PP-ADRC. Moreover, stable open loop is shown to be necessary for stabilizing the closed-loop systems based on SP-ADRC. Furthermore,the performance of rejecting the "total disturbance" at low frequency for these modified ADRCs is evaluated and quantitatively discussed. Finally, the simulations of a boiler turbine system illustrate the theoretical results.

关键词： extended state observer active disturbance rejection control uncertain system time delay predictor

Phase field modeling for the morphological and microstructural evolution of metallic materials under environmental attack

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npj Computational Materials 2021年第1期7卷 1299-1319页

作者： Talha Qasim Ansari Haitao huang San-Qiang Shi Department of Applied Physics and Research Institute of Smart Energy the Hong Kong Polytechnic UniversityHung HomKowloonHong Kong SAR Department of Mechanical Engineering the Hong Kong Polytechnic UniversityHung HomKowloonHong Kong SAR

The complex degradation of metallic materials in aggressive environments can result in morphological and microstructural *** phase-field(PF)method is an effective computational approach to understanding and predicting the morphology,phase change and/or transformation of *** models are based on conserved and non-conserved field variables that represent each phase as a function of space and time coupled with time-dependent equations that describe the *** report summarizes progress in the PF modeling of degradation of metallic materials in aqueous corrosion,hydrogen-assisted cracking,high-temperature metal oxidation in the gas phase and porous structure evolution with insights to future applications.

关键词： corrosion cracking metallic

Beneficial effects of moderate to vigorous physical activity on cardiovascular disease among Chinese adults

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Journal of Geriatric Cardiology 2020年第2期17卷 85-95页

作者： Qiong LIU Fang-Chao LIU Ke-Yong huang Jian-Xin LI Xue-Li YANG Xin-Yan WANG Ji-Chun CHEN Xiao-Qing LIU Jie CAO Chong SHEN ling YU Fang-Hong LU Xian-Ping WU Lian-Cheng ZHAO Ying LI Dong-Sheng HU Xiang-Feng LU Jian-Feng huang Dong-Feng GU Key Laboratory of Cardiovascular Epidemiology Chinese Academy of Medical SciencesBeijingChina Department of Epidemiology Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Division of Epidemiology Guangdong Provincial People’s Hospital and Cardiovascular InstituteGuangzhouChina Department of Epidemiology and Biostatistics School of Public HealthNanjing Medical UniversityNanjingChina Department of Cardiology Fujian Provincial HospitalFuzhouChina Cardio-Cerebrovascular Control and Research Center Institute of Basic MedicineShandong Academy of Medical SciencesJinanChina Sichuan Center for Disease Control and Prevention ChengduChina Department of Prevention Medicine Shenzhen University School of MedicineShenzhenChina

Background In China,lack of evidence remains a significant challenge for the national initiative to promote physical activity(PA).We aimed to quantify the beneficial effects of meeting or maintaining the recommended PA level[150 minutes per week(min/wk)of moderate PA or 75 min/wk of vigorous PA or an equivalent combination]on incident cardiovascular disease(CVD)among Chinese *** We included 100,560 participants without history of CVD from three cohorts in the Prediction for Atherosclerotic Cardiovascular Disease Risk in China(China-PAR)*** proportional hazards models were used to estimate hazard ratios(HRs)and 95%confidence intervals(CIs)for CVD events and its subtypes,including stroke,coronary heart disease,heart failure,and CVD *** During a median follow-up of 7.3 years(range:6–15 years),777,163 person-years and 4693 incident CVD events were *** with participants who were inactive at baseline,the multivariable adjusted HR(95%CI)of developing CVD was 0.74(0.69–0.79)for those who met recommended moderate to vigorous physical activity(MVPA)level at ***,the risk of CVD incidence was reduced with increment of MVPA(Ptrend<0.001),and the HR(95%CI)of highly-active versus inactive category was 0.62(0.56–0.68).Compared with individuals who were inactive both at the baseline and follow-up,those keeping active over the period of follow-up had a substantial lower risk of incident CVD with the HR(95%CI)of 0.57(0.43–0.77).Conclusions The findings demonstrated that meeting and maintaining the recommended MVPA level could reduce the cardiovascular *** adoption of the PA recommendations would have considerable health impacts to the Chinese population.

关键词： Cardiovascular disease China Cohort study Physical activity

Effect of hydrogen on SiC-C films with AES and XPS analyses

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Nuclear Science and Techniques 2003年第1期14卷 56-59页

作者： huang Ning-kang YANG Bin 等 KeyLab.forRadiationPhysicsandTechnologyofEducationMinistryofChina InsituteofNuclearScienceandTechnologySichuanUniversityChengdu610064 KeyLab.forRadiationPhysicsandTechnologyo

SiC-C films with different content of SiC were deposited with r. f. magnetron sputtering followed by argon ion bombardment. These films were then permeated by hydrogen gas under the pressure of 3.23×107 Pa for 3h at 500K. AES and XPS were used to analyze chemical bonding states of C and Si in the SiC-C films as well as contaminating oxygen before and after hydrogen gas permeation in order to study the effect of hydrogen on them. Related mechanism was discussed in this paper.

关键词：碳化硅-碳薄膜 AES XPS 氢气化学键 X射线光电子能谱

FORECASTING TIME SERIES WITH GENETIC PROGRAMMING BASED ON LEAST SQUARE METHOD

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Journal of Systems Science & Complexity 2014年第1期27卷 117-129页

作者： YANG Fengmei LI Meng huang Anqiang LI Jian Faculty of Science Beijing University of Chemical Technology Beijing 100029 China. School of Economics and Management Beihang University Beijing 100083 China School of Economics and Management Beijing University of Chemical Technology Beijing 100029 China.

Although time series are frequently nonlinear in reality, people tend to use linear models to fit them under some assumptJLons unnecessarily in accordance with the truth, which unsurprisingly leads to unsatisfactory performance. This paper proposes a forecast method： Genetic programming based on least square method （GP-LSM）. Inheriting the advantages of genetic algorithm （GA）, without relying on the particular distribution of the data, this method can improve the prediction accuracy because of its ability of fitting nonlinear models, and raise the convergence speed benefitting from the least square method （LSM）. In order to verify the vMidity of this method, the authors compare this method with seasonal auto regression integrated moving average （SARIMA） and back propagation artificial neural networks （BP-ANN）. The results of empirical analysis show that forecast accuracy and direction prediction accuracy of GP-LSM are obviously better than those of the others.

关键词： Forecast genetic programming least square method time series.

Parameter Tuning Method for Dither Compensation of a Pneumatic Proportional Valve with Friction

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Chinese Journal of Mechanical Engineering 2016年第3期29卷 607-614页

作者： WANG Tao SONG Yang huang Leisheng FAN Wei School of Automation Beijing Institute of Technology

In the practical application of pneumatic control devices, the nonlinearity of a pneumatic control valve become the main factor affecting the control effect, which comes mainly from the dynamic friction force. The dynamic friction inside the valve may cause hysteresis and a dead zone. In this paper, a dither compensation mechanism is proposed to reduce negative effects on the basis of analyzing the mechanism of friction force. The specific dither signal（using a sinusoidal signal） was superimposed on the control signal of the valve. Based on the relationship between the parameters of the dither signal and the inherent characteristics of the proportional servo valve, a parameter tuning method was proposed, which uses a displacement sensor to measure the maximum static friction inside the valve. According to the experimental results, the proper amplitude ranges are determined for different pressures. In order to get the optimal parameters of the dither signal, some dither compensation experiments have been carried out on different signal amplitude and gas pressure conditions. Optimal parameters are determined under two kinds of pressure conditions. Using tuning parameters the valve spool displacement experiment has been taken. From the experiment results, hysteresis of the proportional servo valve is significantly reduced. And through simulation and experiments, the cut-off frequency of the proportional valve has also been widened. Therefore after adding the dither signal, the static and dynamic characteristics of the proportional valve are both improved to a certain degree. This research proposes a parameter tuning method of dither signal, and the validity of the method is verified experimentally.

关键词： proportional valve hysteresis dither compensation parameter tuning method

Current research into the use of supercritical CO2 technology in shale gas exploitation

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International Journal of Mining Science and Technology 2019年第5期29卷 739-744页

作者： Wang Meng huang Kai Xie Weidong Dai Xuguang School of Resources and Earth Science China University of Mining&TechnologyXuzhou 221116China Key Laboratory of Coalbed Methane Resource&Reservoir Formation Process Ministry of EducationChina University of Mining&TechnologyXuzhou 221008China College of Geology and Mining Engineering Xinjiang UniversityUrumqi 830046China

The use of supercritical CO2 for shale gas extraction is a promising new *** paper explores current research into this process,looking at analysis of the mechanism of CH4 displacement in nanoporous shale,the positive and negative effects accompanying its use for sequestration as well as organic extraction,the migration of elements and the swelling process,and the macro and micro control mechanisms involved in permeability enhancement in *** directions for future research are also considered through comparison with hydraulic *** research findings indicate that ScCO2 fluid replacement can be used to increase gas production and seal up greenhouse gases as an effective,clean and safe method of shale gas *** is particularly effective for promoting the desorption of CH4 in shale reservoirs that have developed fine neck-wide body pores,and the subtle structural changes effected by ScCO2 fluid in sensitive minerals in reservoirs with a high brittle mineral content also have a positive effect on permeability and storage *** adsorption process has been characterized as consisting of three stages:short-term shrinkage,slow swelling,and stability;an expansion equation has been proposed for CO2/CH4 that incorporates competitive adsorption,collision desorption,and impingement ***2 fracturing has been found to be more effective than hydraulic fracturing for dense reservoirs and more effective at linking up pore-micro-fissure-fracture systems.

关键词： Shale gas Supercritical CO2 Adsorption/desorption Physical properties Geological sequestration

A Distributed Process Management Model for Better Scalability on Multicore Platform

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Chinese Journal of Electronics 2017年第2期26卷 263-270页

作者： CHENG Zhonghan ZHU Runshen CHEN Peng huang Hao State Key Laboratory for Novel Software Technology Nanjing University

With the widespread utilization of multicore processors,operating systems face new challenges on *** lock mechanism used by current monolithic OSs makes some critical modules encounter performance bottlenecks caused by lock *** contention in Linux process lifecycle management results in process Creation,execution and termination(CET) scaling poorly with core count *** from the centralized fashion of Linux,this paper presents a Distributed process management model(DPMM) on microkernel for better *** kernel functions are distributed into message passing servers running on different *** splits the shared data including Process control blocks(PCBs),page pools and buffer caches into these cooperating *** actions including PCB creation/deletion,page allocation/freeing,executable loading and scheduling can be parallelized without *** micro-benchmarks show that DPMM achieves nearly linear performance growth on process CET and outperforms Linux and Minix3 on a 32-Core machine.

关键词： Multicore Microkernel Scalability Process management