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Chinese Physics B 2023年第8期32卷 304-309页

作者：马丽凤杜杉常军陈蔚霖武楚晗石鑫鑫黄翼钟乐穆全全 School of Optics and Photonics Beijing Institute of TechnologyBeijing 100081China Information Science Academy China Electronics Technology Group CorporationBeijing 100098China State Key Laboratory of Applied Optics China Changchun Institute of OpticsFine Mechanics and PhysicsChangchun 130033China

real-time polarization medium-wave infrared(MIR)optical imaging systems enable the acquisition of infrared and polarization information for a *** present,real-time polarization MIR devices face the following problems:poor real-time performance,low transmission and high requirements for fabrication and ***,we aim to improve the performance of real-time polarization imaging systems in the MIR waveband and solve the above-mentioned ***,we propose a MIR polarization imaging system to achieve real-time polarization-modulated imaging with high transmission as well as improved performance based on a pixel-wise metasurface micro-polarization array(PMMPA).The PMMPA element comprises several linear polarization(LP)filters with different polarization *** optimization results demonstrate that the transmittance of the center field of view for the LP filters is up to 77%at a wavelength of4.0μm and an extinction ratio of 88 d *** addition,a near-diffraction-limited real-time MIR imaging optical system is designed with a field of view of 5°and an F-number of *** simulation results show that an MIR polarization imaging system with excellent real-time performance and high transmission is achieved by using the optimized PMMPA ***,the method is compatible with the available optical system design technologies and provides a way to realize real-time polarization imaging in MIR wavebands.

关键词： real-time middle infrared optical imaging system metasurface polarization array

real-time Instability Detection of Centrifugal Compressors Based on Motor Speed Measurements

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Journal of Thermal Science 2023年第1期32卷 310-329页

作者： CHEN Haoxiang ZHUGE Weilin QIAN Yuping ZHANG Yangjun LIU Hongdan State Key Laboratory of Automotive Safety and Energy Tsinghua UniversityBeijing 100084China Chongqing Jiangjin Shipbuilding Industry Corporation China Shipbuilding Industry CorporationChongqing 402263China

Flow instability in the centrifugal compressor should be detected and avoided for stable and safe *** to the popularity of electric centrifugal compressors,instability detection could be achieved by measuring motor signals instead of traditional aerodynamic *** this paper,the feasibility of instability detection by motor signals(*** speed and phase current)was studied *** physical structure and control method of the electric centrifugal compressor were discussed to reveal the potential of instability detection by motor *** pressure signals and motor signals measured during unsteady experiments were analyzed in the time domain and frequency *** of these signals were then compared under different operating conditions to indicate the feasibility of instability detection by motor ***,the ability of Short-time Fourier Transform(STFT)of rotating speed signals in real-time instability detection was *** showed that the rotating speed signal is a good alternate for instability detection in spite of signal distortion,while the phase current signal can only detect surge due to the low resolution of the *** on the variations of the amplitude and frequency of rotating speed signals,the real-time instability can be captured accurately by STFT with a window size of 0.5 ***,the interference caused by the controller can be removed by STFT.

关键词： centrifugal compressor instability detection real-time rotating speed STFT

real-time electrical detection of epidermal skin MoS2 biosensor for point-of-care diagnostics

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Nano Research 2017年第3期10卷 767-775页

作者： Geonwook Yoo Heekyeong Park Minjung Kim Won Geun Song Seokhwan Jeong Min Hyung Kim Hyungbeen Lee Sang Woo Lee Young KiHong Min Goo Lee Sungho Lee Sunkook Kim School of Electronic Engineering Soongsil University Seou106978 Republic of Korea Multi-Functional Nano/Bio Electronics Lab. Kyung Hee University Gyeonggi 17104 Republic of Korea Department of Biomedical Engineering Yonsei University Wonju 26493 Republic of Korea Korea Electronics Technology Institute Gyeonggi 13488 Republic of Korea

Various approaches have been proposed for point-of-care diagnostics, and in particular, optical detection is preferred because it is relatively simple and fast. At the same time, field-effect transistor （FET）-based biosensors have attracted great attention because they can provide highly sensitive and label-free detection. In this work we present highly sensitive, epidermal skin-type point-of-care devices with system-level integration of flexible MOS2 FET biosensors, read-out circuits, and light-emitting diode （LEDs） that enable real-time detection of prostate cancer antigens （PSA）. Regardless of the physical forms or mechanical stress conditions, our proposed high-performance MoS2 biosensors can detect a PSA concentration of 1 ***-1 without specific surface treatment for anti-PSA immobilization on the MoS2 surface on which we characterize and confirm physisorption of anti-PSA using Kelvin probe force microscopy （KPFM） and tapping-mode atomic force microscopy （tm-AFM）. Furthermore, current modulation induced by the binding process was stably maintained for longer than 2-3 min. The results indicate that flexible MoS2-based FET biosensors have great potential for point-of-care diagnostics for prostate cancer as well as other biomarkers.

关键词： epidermal skin biomarker MoS2 biosensor real-time point-of-care diagnostics

real-time calculation of fragment velocity for cylindrical warheads

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Defence Technology（防务技术） 2019年第3期15卷 264-271页

作者： David Felix Ian Colwill Elias Stipidis Institution of Engineering and Technology Stevenage England Member of British Computer Society London Institute of Electrical and Electronics Engineers London

To simulate explosion fragments, it is necessary to predict many variables such as fragment velocity, size distribution and projection angle. For active protection systems these predictions need to be made very quickly, before the weapon hits the target. Fast predictions also need to be made in real time simulations when the impact of many different computer models need to be assessed. The research presented in this paper focuses on creating a fast and accurate estimate of one of these variables - the initial fragment velocity. The Gurney equation was the first equation to calculate initial fragment velocity. This equation, sometimes with modifications, is still used today where finite element analysis or complex mathematical approaches are considered too computationally expensive. This paper enhances and improves Breech’s two-dimensional Gurney equation using available empirical data and the principals of conservation of momentum and energy. The results are computationally quick, providing improved accuracy for estimating initial fragment velocity. This will allow the developed model to be available for real-time simulation and fast computation, with improved accuracy when compared to existing approaches.

关键词： Initial fragment velocity real-time simulation Cylindrical explosion

real-time data processing method for CO_(2) dispersion interferometer on EAST

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Plasma Science and Technology 2024年第8期26卷 121-126页

作者：张家敏姚远刘郁阳储宇奇阮天翼张耀刘海庆揭银先凌必利 Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031People’s Republic of China University of Science and Technology of China Hefei 230026People’s Republic of China University of California Los Angeles Los AngelesCalifornia 90095United States of America

A real-time data processing system is designed for the carbon dioxide dispersion interferometer(CO_(2)-DI)on *** system utilizes the parallel and pipelining capabilities of an fieldprogrammable gate array(FPGA)to digitize and process the intensity of signals from the ***,the real-time electron density signals are exported through a digital-to-analog converter(DAC)module in the form of analog *** system has been successfully applied in the CO_(2)-DI system to provide low-latency electron density input to the plasma control system on *** results of the latest campaign with long-pulse discharges on EAST(2022–2023)demonstrate that the system can respond effectively in the case of rapid density changes,proving its reliability and accuracy for future electron density calculation.

关键词： dispersion interferometer real-time electron density FPGA EAST

real-time observation of bainite formation at heterogeneous phases in a high-strength weathering steel

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Journal of Iron and Steel Research International 2019年第3期26卷 301-309页

作者： Jian Cheng Jia-sheng Qing Yue-hua Guo Hou-fa Shen Key Laboratory for Advanced Materials Processing Technology Ministry of EducationSchool of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Pangang Group Research Institute Co. Ltd.State Key Laboratory of Vanadium and Titanium Comprehensive UtilizationPanzhihua 617000SichuanChina

Due to the excellent comprehensive mechanical properties and toughness of bainite steels,bainite is regarded as a most desirable microstructure for the new generation of high-strength weathering *** formation of bainite was observed in real time in a high-strength weathering steel,and the results showed that bainite laths show impingement during phase *** preferred regions of nucleation sites were identified,and the growth rate of bainite was *** growth mechanism of bainite was demonstrated to exhibit growth rate contributions from both the diffusion mechanism and the shear ***,the heterogeneous phases that form preferred sites for bainite nucleation were quantitatively identified by scanning electron microscopy(SEM),energy-dispersive X-ray spectrometry(EDS),and calculation of phase diagram(CALPHAD).The austenite grain sizes in crease with increasing austenite temperature,which leads to longer bainite *** influence of a small lattice disregistry between the heterogeneous phases and bainite on the bainite nucleation was *** disregistries between the favorable heterogeneous phases of VN,VC,TiN,or TiC and the ot-Fe in bainite are 2.9,3.1,3.9,and 4.6%,***,VN,VC,TiN,and TiC can act as highly effective nuclei for bainite during the bainite transformation.

关键词： Bainite real-time observation Plasticity Phase transformation Weathering steel

real-time object tracking via compressive feature selection

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Frontiers of Computer Science 2016年第4期10卷 689-701页

作者： Kang LI Fazhi HE Xiao CHEN School of Computer Science Wuhan University Wuhan 430072 China

Recently, compressive tracking （CT） has been widely proposed for its efficiency, accuracy and robustness on many challenging sequences. Its appearance model employs non-adaptive random projections that preserve the structure of the image feature space. A very sparse measurement matrix is used to extract features by multiplying it with the feature vector of the image patch. An adaptive Bayes classifier is trained using both positive samples and negative samples to separate the target from background. On the CT frame- work, however, some features used for classification have weak discriminative abilities, which reduces the accuracy of the strong classifier. In this paper, we present an online compressive feature selection algorithm（CFS） based on the CT framework. It selects the features which have the largest margin when using them to classify positive samples and negative samples. For features that are not selected, we define a random learning rate to update them slowly, It makes those weak classifiers preserve more target information, which relieves the drift when the appearance of the target changes heavily. Therefore, the classifier trained with those discriminative features couples its score in many challenging sequences, which leads to a more robust tracker. Numerous experiments show that our tracker could achieve superior result beyond many state-of-the-art trackers.

关键词： object tracking compressive sensing supervised learning real-time

real-time pricing method for smart grids based on complementarity problem

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Journal of Modern Power Systems and Clean Energy 2019年第5期7卷 1280-1293页

作者： Hongjie WANG Yan GAO School of Management University of Shanghai for Science and TechnologyShanghai 200093China

Considering a demand response(DR)based social welfare maximization model,a complementarity problem based on the Karush-Kuhn-Tuker condition is described,which is a non-dual method for determining real-time price for smart *** Lagrange multiplier in the dual method,which is used to determine the basic electricity price,is applied in the *** proposed method computes the optimal electricity consumption,price and *** to the electricity price,users can arrange their electricity equipment reasonably to reduce the consumption pressure at peak *** model aims to encourage users to actively participate in the DR and realize peak cutting and valley *** addition,the model considers different utility functions representing three types of ***,a Jacobian smoothing version of Newton method is used to solve the *** simulations of the model validate the rationality and feasibility of the proposed method.

关键词： Smart grids real-time pricing Shadow price Complementarity problem Smoothing method

real-time performance of DAE and ODE based estimators evaluated on a diesel engine

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Science China(Information Sciences) 2018年第7期61卷 27-39页

作者： Erik H?CKERDAL Erik FRISK Lars ERIKSSON Scania CV AB Vehicular Systems Link?ping University

Computation and sampling time requirements for real-time implementation of observers is studied. A common procedure for state estimation and observer design is to have a system model in continuous time that is converted to sampled time with Euler forward method and then the observer is designed and implemented in sampled time in the real time system. When considering state estimation in real time control systems for production there are often limited computational resources. This becomes especially apparent when designing observers for stiff systems since the discretized implementation requires small step lengths to ensure stability. One way to reduce the computational burden, is to reduce the model stiffness by approximating the fast dynamics with instantaneous relations, transforming an ordinary differential equations(ODE)model into a differential algebraic equation(DAE) model. Performance and sampling frequency limitations for extended Kalman filter(EKF)'s based on both the original ODE model and the reduced DAE model are here analyzed and compared for an industrial system. Furthermore, the effect of using backward Euler instead of forward Euler when discretizing the continuous time model is also analyzed. The ideas are evaluated using measurement data from a diesel engine. The engine is equipped with throttle, exhaust gas recirculation(EGR), and variable geometry turbines(VGT) and the stiff model dynamics arise as a consequence of the throttle between two control volumes in the air intake system. The process of simplifying and modifying the stiff ODE model to a DAE model is also discussed. The analysis of the computational effort shows that even though the ODE, for each time-update, is less computationally demanding than the resulting DAE, an EKF based on the DAE model achieves better estimation performance than one based on the ODE with less computational effort. The main gain with the DAE based EKF is that it allows increased step lengths without degrading the

关键词： estimation learning DAE ODE EKF observability real-time

real-time mosaicking for infrared videos from an oblique sweeping camera

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Chinese Journal of Aeronautics 2021年第1期34卷 309-319页

作者： Jiazhen LU Fangde SUN Jing DONG Songlai HAN Ang SU School of Aeronautics and Astronautics Central South UniversityChangsha 410083China Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

Image mosaicking is widely used in Geographic Information Systems(GISs)for largescale ground surface ***,most existing mosaicking methods can only be used in offline processing due to the enormous amounts of *** this paper,we propose a novel and practical algorithm for real-time infrared video *** achieve this,a novel fast template matching algorithm based on Sum of Cosine Differences(SCD)is proposed to coarsely match the sequential *** high speed of the proposed template matching algorithm is obtained by computing correlation with Fast Fourier Transform(FFT).We also propose a novel fast Least Squares Matching(LSM)algorithm for inter-frame fine registration,which can significantly reduce the computation without degrading the matching *** addition,the proposed fast LSM can effectively adapt for noise degradation and geometric *** on the proposed fast template matching algorithm and fine registration algorithm,we develop a practical real-time mosaicking approach which can produce seamless mosaic image highly *** on synthetic and real-world datasets demonstrate that the proposed algorithm is not just computationally efficient but also robust against various noise distortions.

关键词： Fast Fourier transform Least squares matching Map fusion Mosaic real-time Template matching