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Communications in Theoretical Physics 2011年第3期55卷 506-512页

作者： gu An-Na liang Xian-Ting Department of Physics and Institute of Modern Physics Ningbo University Ningbo 315211 China

In this paper, we investigate a two electronic level system with vibrational modes coupled to a Brownian oscillator bath. The difference frequency generation （DFG） signals and sum frequency generation （SFG） signals are calculated. It is shown that, for the same model, the SFG signals are more sensitive than the DFG signals to the changes of the vibrational modes of the electronic two-level system. Because the SFG conversion efficiency can be improved by using the time-delay method, the findings in this paper predict that the SFG spectrum may probe the changes of the microstructure more effectively.

关键词： difference frequency signals sum frequency signals response functions susceptibility

Syntheses,Crystal Structures and Complexing Properties of 1,3-Distal Calix[4]arene Schiff Bases

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Chemical Research in Chinese Universities 2010年第1期26卷 38-45页

作者： LI liang gu Wei-wei YAN Chao-guo College of Chemistry ＆ Chemical Engineering Yangzhou University Yangzhou 225002 P R. China

Novel 1,3-distal p-tert-butylcalix[4]arene Schiff bases were efficiently synthesized in three steps. At first p-tert-hutylcalix[4]arene was reacted with N-2-hydroxyethylphthalimide catalyzed by TPP/DEAD or alkylated with ω-hatoalkylphthalimide in the system of K2CO3/KI/CH3COCH3 to give 1,3-distal diphthalimidoalkyl calixarenes, which were in turn hydrazinolyzed to give diaminoalkyl calixarenes. Then with the aid of the condensation of active calixarene amines with salicylaldehyde, 2-hydroxy-l-naphthaldehyde or pyridine-2-carboxaldehyde, a series of 1,3-distal calixarene Schiff bases was prepared in satisfied yields. The single crystal structures and complexing properties of these Schiff bases for transition metal ions were studied.

关键词： Calixarene Schiffbase Crystal structure Metal complex UV spectroscopy

Integrated Active Suspension and Anti-Lock Braking Control for Four-Wheel-Independent-Drive Electric Vehicles

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 87-98页

作者： Ze Zhao Lei Zhang Xiaoling Ding Zhiqiang Zhang Shaohua Li liang gu National Engineering Research Center for Electric Vehicles Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China

This paper presents an integrated control scheme for enhancing the ride comfort and handling performance of a four-wheel-independent-drive electric vehicle through the coordination of active suspension system(ASS)and anti-lock braking system(ABS).First,a longitudinal-vertical coupled vehicle dynamics model is established by integrating a road input *** the coupling mechanisms between longitudinal and vertical vehicle dynamics are *** ASS-ABS integrated control system is proposed,utilizing an H∞controller for ASS to optimize load transfer effect and a neural network sliding mode control for ABS ***,the effectiveness of the proposed control scheme is evaluated through comprehensive tests conducted on a hardware-in-loop(HIL)test *** HIL test results demonstrate that the proposed control scheme can significantly improve the braking performance and ride comfort compared to conventional ABS control methods.

关键词： Four-wheel-independent-drive electric vehicles Active suspension system(ASS) Anti-lock braking system(ABS) Vertical-longitudinal vehicle dynamics

Effect of Tire Repeated Root Modal on Tire Modelling with Experimental Modal

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Journal of Beijing Institute of Technology 2017年第1期26卷 67-74页

作者： Zhenfeng Wang Yongchang Du Mingming Dong liang gu School of Mechanical Engineering Beijing Institute of Technology State Key Laboratory of Automotive Safety and Energy Tsinghua University

The effect of tire repeated root modal（RRM）on tire modeling with an experimental modal is ***,a radial tire with radial and tangential RRMs is tested and *** multi-point exciting of the radial tire,a multiple reference frequency domain method based on a least squares（LMS PolyMAX）algorithm is used to identify modal ***,modal stability diagram（MSD）,modal indication function（MIF）and modal assurance criteria（Auto-MAC）matrix are utilized to induce multiple inputs multiple outputs（MIMO）frequency response function（FRF）*** tests reveal that notable repeated roots exist in both radial and tangential response *** modal frequencies and damping factors are approximately the same,the amplitudes of modal vectors are in the same order of magnitude,and the mode shapes are *** on the works mentioned,the method of trigonometric series modal shapes fitting is adopted,the effects of RRM model on tire modeling with a vertical experimental modal are *** final results show that the effects of considering the RRM shapes are equivalent to the tire mode shapes depended on rotating the tire’s different exciting points during tire modeling,and since considering the RRM,the tire mode shapes can be unified and fixed during tire modeling.

关键词： modal test repeated root modal ploy MAX method tire model

A Power Data Anomaly Detection Model Based on Deep Learning with Adaptive Feature Fusion

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Computers, Materials & Continua 2024年第6期79卷 4045-4061页

作者： Xiu Liu liang gu Xin Gong Long An Xurui Gao Juying Wu State Grid Information&Telecommunication Co.of SEPC Big Data CenterTaiyuan030000China

With the popularisation of intelligent power,power devices have different shapes,numbers and *** means that the power data has distributional variability,the model learning process cannot achieve sufficient extraction of data features,which seriously affects the accuracy and performance of anomaly ***,this paper proposes a deep learning-based anomaly detection model for power data,which integrates a data alignment enhancement technique based on random sampling and an adaptive feature fusion method leveraging dimension *** at the distribution variability of power data,this paper developed a sliding window-based data adjustment method for this model,which solves the problem of high-dimensional feature noise and low-dimensional missing *** address the problem of insufficient feature fusion,an adaptive feature fusion method based on feature dimension reduction and dictionary learning is proposed to improve the anomaly data detection accuracy of the *** order to verify the effectiveness of the proposed method,we conducted effectiveness comparisons through elimination *** experimental results show that compared with the traditional anomaly detection methods,the method proposed in this paper not only has an advantage in model accuracy,but also reduces the amount of parameter calculation of the model in the process of feature matching and improves the detection speed.

关键词： Data alignment dimension reduction feature fusion data anomaly detection deep learning

Genetic analysis and gene fine mapping of a rolling leaf mutant (rl_(11(t))) in rice (Oryza sativa L.)

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Chinese Science Bulletin 2010年第17期55卷 1763-1769页

作者： ZHOU Yong FANG YunXia ZHU JinYan LI ShengQiang gu Fei gu MingHong liang guoHua Jiangsu Key Laboratory for Crop Genetics and Physiology/Jiangsu Key Laboratory of Plant Functional Genomics Yangzhou University Yangzhou 225009 China

The exploration of new genes controlling rice leaf shape is an important foundation for rice functional genomics and plant architecture improvement. In the present study, we identified a rolling leaf mutant from indica variety Yuefeng B, named rl11(t), which exhibited reduced plant height, rolling and narrow leaves. Leaves in rl11(t) mutant showed abnormal number and morphology of veins compared with those in wild type plants. In addition, rl11(t) mutant was less sensitive to the inhibitory effect of auxin than the wild type. Genetic analysis suggested that the mutant was controlled by a single recessive gene. Gene Rl11(t) was initially mapped between SSR markers RM6089 and RM124 on chromosome 4. Thirty-two new STS markers around the Rl11(t) region were developed for fine mapping. A physical map encompassing the Rl11(t) locus was constructed and the target gene was finally delimited to a 31.6 kb window between STS4-25 and STS4-26 on BAC AL606645. This provides useful information for cloning of Rl11(t) gene.

关键词：功能基因组学精细定位遗传分析突变体 Oryza 水稻动叶叶片形状

Improving Performance of Virtual Machine Covert Timing Channel Through Optimized Run-Length Encoding

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Journal of Computer Science & Technology 2023年第4期38卷 793-806页

作者：王翀陈荣亮古亮 Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen 518055China Sangfor Technologies Inc. Shenzhen 518055China Shenzhen Key Laboratory for Exascale Engineering and Scientific Computing Shenzhen 518055China

With its wider acceptability,cloud can host a diverse set of data and applications ranging from entertainment to personal to *** foundation of cloud computing is based on virtual machines where boundaries among the application data are very thin,and the potential of data leakage exists all the *** instance,a virtual machine covert timing channel is an aggressive mechanism to leak confidential information through shared components or networks by violating isolation and security policies in *** performance of a covert timing channel(covert channel)is crucial to adversaries and attempts have been made to improve the performance of covert timing channels by advancing the encoding mechanism and covert information *** promising,the redundancy of the covert message is mainly *** paper applies three encoding schemes namely run-length,Huffman,and arithmetic encoding schemes for data compression of a virtual machine covert timing channel by exploiting ***,the paper studies the performance of such channels according to their ***,we show that these encoding schemes still contain redundancy in a covert channel scenario,and thereby a new encoding scheme namely optimized Runlength encoding(OptRLE)is presented that greatly enhances the performance of a covert timing *** optimizations schemes adopted by OptRLE are also discussed,and a mathematical model of the behavior of an OptRLE-based covert timing channel is *** theoretical capacity of a channel can be obtained using the proposed *** analysis reveals that OptRLE further improves the performance of a covert timing channel,in addition to the effects of the *** result shows how OptRLE affects the size of covert data and the capacity of covert timing channels,and why the performance of the covert timing channel is improved.

关键词： covert storage channel information security covert channel threat evaluation anti-detection criterion covert channel restriction

Dynamic Motion Resistance for Tracked Vehicle

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Journal of Beijing Institute of Technology 2017年第3期26卷 334-339页

作者： Kai Zhao Mingming Dong Zhiguo Sang Feng Liu liang gu School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China

Based on previous achievements,a dynamic pressure-sinkage equation for saturated clay is ***,aquasi-static penetration rate is selected,and the ratio of the dynamic penetration rate to the quasi-static rate is used to characterize the degree of dynamic effect,then theβth power of the ratio is used to quantify the dynamic effect of *** dynamic effect exponentβis obtained using penetration tests with different penetration ***,a dynamic motion resistance equation for a tracked vehicle is established based on the dynamic pressure-sinkage *** equation incorporates both penetration and bulldozing ***,a series of simulation experiments with varying travel speeds and slip rates is carried *** results show that an increase in the speed leads to stronger terrain stiffness,resulting in a decrease in sinkage and motion ***,the enhancement effect becomes weaker with an increase in the travel speed.

关键词： dynamic motion resistance tracked vehicle sinkage slip

Vibration-Based Terrain Classification for Autonomous Vehicles

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Journal of Beijing Institute of Technology 2017年第4期26卷 440-448页

作者： Kai Zhao Mingming Dong Zhiguo Wang Yanxi Han liang gu School of Mechanical Engineering Beijing Institute of Technology Beijing 100081 China Beijing North Vehicle Group Corporation Beijing 100072 China

A method for terrain classification based on vibration response resulted from wheel-terrain interaction is presented. Four types of terrains including sine,gravel,cement and pebble were *** vibration data were collected by two single axis accelerometers and a triaxial seat pad accelerometer,and five data sources were utilized. The feature vectors were obtained by combining features extracted from amplitude domain,frequency domain,and time-frequency domain. The ReliefF algorithm was used to evaluate the importance of attributes; accordingly,the optimal feature subsets were selected. Further,the predicted class was determined by fusion of outputs provided by five data sources. Finally,a voting algorithm,wherein a class with the most frequent occurrence is the predicted class,was employed. In addition,four different classifiers,namely support vector machine,k-nearest neighbors,Nave Bayes,and decision tree,were used to perform the classification and to test the proposed method. The results have shown that performances of all classifiers are ***,the proposed method is proved to be effective.

关键词： ReliefF algorithm terrain classification vibration voting algorithm

Control Research of Dual Chamber Hydro-Pneumatic Suspension

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Journal of Beijing Institute of Technology 2018年第4期27卷 510-517页

作者： Jinwei Sun Mingming Dong Zhiguo Wang Baoyu Li liang gu School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China Beijing North Vehicle Group Corporation Beijing 100072China

Vehicle riding comfort and handling stability are directly affected by suspension performance.A novel dual chamber hydro-pneumatic(DCHP)suspension system is developed in this *** on the structural analysis of the DCHP suspension,an equivalent suspension model is proposed for the control purpose.A cuckoo search(CS)based fuzzy PID controller is proposed for the control of the DCHP suspension *** proposed controller combines the advantage of fuzzy logic and PID controller,and CS algorithm is used to regulate the membership functions and PID *** with tradition LQR controller and passive suspension system,the CSFPID controller can reduce the sprung mass acceleration,and at the same time with no deterioration of tire deflection.

关键词： vehicle dynamics dual chamber hydro-pneumatic(DCHP)suspension cuckoo search(CS) fuzzy PID