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parameter optimization for an All-Time Star Sensor Based on Field of View Gated Technology

IEEE SENSORS JOURNAL 2024年第22期24卷 38015-38024页

作者： Zhong, Shaoyuan Wei, Xinguo Jiang, Jie Li, Jian Wang, Gangyi Zhang, Guangjun Fang, Liang Beihang Univ Sch Instrument Sci & Opto Elect Engn Beijing 100191 Peoples R China Chinese Acad Sci Inst Opt & Elect Chengdu 610000 Peoples R China

The intense atmospheric background in near-earth space has huge interference on the star detection for all-time star sensors. To observe and track stars, traditional all-time star sensors with narrow field of view (FOV) must be installed on turntable platforms, which cannot achieve autonomous celestial attitude measurement. The innovative all-time star sensor based on FOV-gated technology controls the microshutter and microlens array, enabling rapid switching to subdivide the wide FOV and gate a narrow FOV. This system ensures the detection of multiple stars simultaneously by suppressing atmospheric background radiation, thereby achieving autonomous attitude determination. For the all-time star sensor, the accuracy of attitude measurement is not only related to system parameters but also to atmospheric radiation and transmission. Current parameter optimization methods are constrained by specific observation conditions, limiting their applicability across diverse scenarios and temporal variations. To overcome these limitations, we developed an analytical model that accounts for the distribution of spatiotemporal observation conditions, including the probability distribution of the solar zenith angle. Based on this model, the attitude accuracy of the star sensor under all spatiotemporal conditions is weighted and employed as the global optimization objective. An optimal design scheme was provided through optimization, leading to the fabrication of an actual optical lens, which was subsequently used to assemble a prototype. A ground-based experiment was conducted to validate the accuracy of the star detection model, followed by a simulation that confirmed the proposed design satisfies the requirements in the entire celestial sphere.

关键词： Stars Sensors Atmospheric modeling Accuracy Atmospheric measurements Analytical models Logic gates Sensor systems Optical imaging Image sensors All-time star sensor detection accuracy detection model parameter optimization method

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Quarterly Data Forecasting method Based on Extended Grey GM(2, 1, Σsin) Model and Its Application in China's Quarterly GDP Forecasting

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COMPUTATIONAL ECONOMICS 2024年第4期64卷 2385-2412页

作者： Cheng, Maolin Liu, Bin Suzhou Univ Sci & Technol Dept Stat Suzhou 215009 Peoples R China Suzhou Univ Sci & Technol Dept Finance Suzhou 215009 Peoples R China

In the grey prediction, the GM(N, 1) model is an important type. There are relatively more studies on the GM(2, 1) model, but most scholars used the GM(2, 1) model to explore the prediction problem of monotone time sequences and only a few scholars used the GM(2, 1) model to predict non-monotone time sequences, such as the quarterly variation sequence. The paper uses the GM(2, 1) model to predict quarterly variation sequences. To improve the modeling precision, the paper makes improvements in the following three aspects: (1) to improve quarterly data's adaptability to the model, the paper improves the original time sequence, i.e. introducing a quarterly multiple factor for a data transformation of the original time sequence;(2) to make the model present quarterly data's variation characteristics, the paper improves the traditional GM(2, 1) model's structure, i.e. introducing a superposed trigonometric function to extend the model's grey action;(3) to improve the model's simulation and prediction precision, the paper improves the parameter optimization method, i.e. considering the minimum of the maximum of average simulation and prediction relative errors as the objective function. The results of this study are as follows: (1) the introduction of seasonal multiplication factor enhances the adaptability of quarterly data to the model;(2) the expanded model can reflect the characteristics of seasonal data changes;(3) examples show that the simulation and prediction accuracies of the expanded model are very high, and the average simulation relative error is only 1.44%, and the average prediction relative error is only 1.43%. The errors are very small;(4) the simulation and prediction accuracies of the extended model are significantly higher than those of the traditional and comparative models.

关键词： GM(2,1) model Quarterly data parameter optimization method Prediction C13 C32 C53 E27

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The Extended Grey GM(2,1,Σexp(ct))Model and Its Application in the Predictions

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Journal of Systems Science and Information 2023年第2期11卷 245-263页

作者： Maolin CHENG Bin LIU School of Mathematical Sciences Suzhou University of Science and TechnologySuzhou 215009China School of Business Suzhou University of Science and TechnologySuzhou 215009China

The conventional grey GM(2,1)model built for the fast growing time sequence generally has big *** improve the modeling precision,the paper improves from the following two aspects:First,the paper transforms the accumulated generating sequence of original time sequence quantitatively to make the transformed time sequence have the better adaptability to the model;second,the paper extends the conventional grey GM(2,1)model’s structure to make the extended model meet the variation law of fast growing sequence *** extended grey model is called the GM(2,1,Σexp(ct))*** paper offers the parameter optimization method and the solving method of time response sequence of GM(2,1,Σexp(ct))*** the model and methods proposed,the paper builds the GM(2,1,Σexp(ct))models for the natural gas consumption of China and Chongqing City,China,*** show that the models built have high simulation precision and prediction precision.

关键词： GM(2,1,Σexp(ct))model parameter optimization method time response equation natural gas consumption prediction

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Study on parameter acquisition and optimization methods of JH-2 constitutive model for ceramic

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INTERNATIONAL JOURNAL OF IMPACT ENGINEERING 2023年 172卷

作者： An, Rui Wang, Yangwei Fu, Qiang Tan, Yan Cheng, Huanwu Cheng, Xingwang Wang, Fuchi Beijing Inst Technol Sch Mat Sci & Engn Beijing 100081 Peoples R China Natl Key Lab Sci & Technol Mat Shock & Impact Beijing 100081 Peoples R China Beijing Inst Technol Chongqing Innovat Ctr Chongqing 401147 Peoples R China 5 Zhongguancun South St Beijing Peoples R China

In this study, based on AD995 and sapphire, the method of obtaining and optimizing the key parameters of the Johnson-Holmquist constitutive model (JH-2 model) for typical brittle materials was established. The parameter acquisition method was optimized by analyzing the limitations of the traditional parameter acquisition method. The value ranges of the intact strength parameters were calculated using the results of the mechanical property tests of the materials;the well-fitted intact strength parameters (A, N, C and T) were obtained by combining with the parameter optimization procedure. The sensitivity of the dynamic compression test and the penetration process to the damage-related parameters (B, M, D1 and D2) was analyzed by numerical simulation methods. The damage-related parameters in the JH-2 model were obtained using a chaotic global optimization algorithm combined with numerical simulations of dynamic compression tests and penetration tests. The calculation ac-curacy of the traditional and optimized parameters were compared by numerical simulation results of pene-tration tests for different ceramic composite structures. The simulation results of the optimized parameters basically match with the experimental results, and the calculation accuracy is much higher than that of the traditional parameters, which verifies the effectiveness and superiority of the parameter optimization method.

关键词： JH-2 constitutive model Numerical simulation parameter optimization method Ballistic impact

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Dynamics of a Euler-Bernoulli beam on nonlinear viscoelastic foundations: a parameter space analysis

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JOURNAL OF THE BRAZILIAN SOCIETY OF MECHANICAL SCIENCES AND ENGINEERING 2020年第11期42卷 1-14页

作者： Soares, Gilson V. Ladeira, Denis G. Oliveira, Adelcio C. CEFET MG Programa Pos Grad Modelagem Matemat & Computac Belo Horizonte MG Brazil Secretaria Estadual Educ Minas Gerais Belo Horizonte MG Brazil Univ Fed Sao Joao del Rei Dept Estat Fis & Matemat Defim CP 131 BR-36420000 Ouro Branco MG Brazil

The dynamics and spectrum of vibrations of an uniform Euler-Bernoulli beam on nonlinear viscoelastic foundations are investigated in parameter space. An alternative method of approach based on mean-field approximation is proposed. Spatial and temporal solution are obtained in an interactive way. The spectrum is reached directly from spatial solutions. It was shown that the system exhibits sudden birth and death of chaotic attractors (crises) and that there are periodic windows immersed in chaotic regions. In this work it was investigated the dynamics of a beam of Euler-Bernoulli with viscous and dynamic support. It is presented, then, a model to treat this type of problem, which is nonlinear and non-autonomous. The dynamics of the model presents a complex behavior, being in some cases sensitive to the initial conditions. Changing properly the parameters the dynamics goes from chaotic behavior to periodic regime. As the system is forced and dissipative, complex structures in the parameter space, known as shrimps, arise. Also, it was found that the spatial solution is not sensitive to the dynamics, although they are coupled. However, the dynamics is very sensitive to the mean quadratic deformation of the beam and, therefore, it is related to the vibration modes obtained in the spatial solution.

关键词： Chaos Euler-Bernoulli beam parameter space Shrimps parameter optimization method

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Optimal Operation of Danjiangkou Reservoir Using Improved Hedging Model and Considering the Effects of Historical Decisions

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JOURNAL OF WATER RESOURCES PLANNING AND MANAGEMENT 2018年第1期144卷 04017080-04017080页

作者： Sun, Xiaozhong Ma, Chao Lian, Jijian Tianjin Univ State Key Lab Hydraul Engn Simulat & Safety Tianjin 311100 Peoples R China Powerchina Huadong Engn Corp Ltd Planning & Dev Res Inst Hangzhou 311100 Zhejiang Peoples R China

For reservoirs with multiple water demands, losses in water use utility because of shortages in the water supply from historical operation decisions can be considered information to improve the current decisions. This study proposes an improved hedging model that uses the parameter optimization method to incorporate the effects of historical decisions. A new cumulative water shortage impact index is proposed to evaluate the severity of historical water shortages and their impact on release decisions, and the Palmer drought severity index (PDSI) is incorporated to improve the hedging model. Based on the new index, a weighting factor of previously derived hedging rules is optimized, which represents the relative importance of water release and water storage, and more realistic hedging rules and operation decisions for reservoir managers are obtained. The new model is employed at the Danjiangkou Reservoir, which serves as one of the major storage points on the middle route of the south-to-north water transfer project (SNWTP). The results show the following: (1)when the reservoir inflow is insufficient, the initial weighting factor (initial w) and its corresponding scaling factor can be obtained to guide decisions by considering the forecasted inflow, starting regulation level (SRL), and expected water level at the end of year (WLE);(2)by following the optimal solution, the water delivery process becomes more uniform, and a more reasonable water supply order can be determined according to the unit water supply benefit for each water user;and (3)in an average dry year and in the driest year in the historical record, with initial w values of 0.7 and 0.15, the SRL is greater than 158m, and the delivery rates of the SNWTP water in the initial stages should be controlled at approximately 0.85 and 0.4, respectively.

关键词： Historical decision effect Improved hedging model parameter optimization method Optimal operation decision Danjiangkou Reservoir Multiple water demands South-to-north water transfer project (SNWTP)

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Stabilization and optimal control of nonholonomic mobile robot

Stabilization and optimal control of nonholonomic mobile rob...

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8th International Conference on Control, Automation, Robotics and Vision (ICARCV 2004)

作者： Li, S Ma, GL Hu, WL Nanjing Univ Sci & Technol Dept Automat Jiangsu 210094 Peoples R China

ISBN: (纸本)0780386531

The stabilization and optimal control of nonholonomic mobile robot has been an important control problem in the mobile robot research area in the past few years. In this paper, a controller with two parameters for the stabilization of a mobile robot with two-wheel is proposed. And a procedure of parameters optimization using the Genetic Algorithm is presented in order to minimize the performance criterion function. Finally, simulation results illustrate the effectiveness of the proposed controller and parameter optimization method.

关键词： mobile robots genetic algorithms optimal control stability nonholonomic mobile robot stabilization optimal control performance criterion function parameter optimization method genetic algorithm

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Chaos attractors of ventricular elastance to evaluate cardiac performance

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ARTIFICIAL ORGANS 2003年第1期27卷 104-107页

作者： Yambe, T Yoshizawa, M Taira, R Tanaka, A Tabayashi, K Sasada, H Nitta, S Tohoku Univ Inst Dev Aging & Canc Dept Med Engn & Cardiol Aoba Ku Sendai Miyagi 98077 Japan Tohoku Univ Informat Synergy Ctr Sendai Miyagi 98077 Japan Tohoku Univ Grad Sch Engn Sendai Miyagi 98077 Japan Tohoku Univ Grad Sch Med Sendai Miyagi 98077 Japan Tohoku Univ Grad Sch Agr Sendai Miyagi 98077 Japan

Quantitative evaluation of cardiac function is very important in the clinical application of a ventricular assist device. This article reports a new evaluating method of E max, which is the most reliable parameter to evaluate cardiac function. Fluctuation in the E max time series data was evaluated by the nonlinear mathematical analyzing method including chaos and fractal theory. Experimental goats were anesthetized with halothane inhalation, and left ventricular volume and pressure were measured with other hemodynamic parameters to evaluate E max during various drug administrations. E max was evaluated by two methods. One was the conventional pressure volume loop evaluation and the other was the parameter optimization method without left ventricular volume data. As a result, E max evaluated by the parameter optimization method correlated well with the E max with conventional PV curve. Furthermore, interesting results were obtained. There were rhythmical fluctuations in the E max time series data. By the methodology of Takens, E max time series data was embedded into the phase space and a strange attractor was observed. These results may be important when considering E max evaluation during left ventricular assistance.

关键词： fluctuation E max parameter optimization method ventricular assist device deterministic chaos ventricular elastance cardiac function

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Chaos attractors of ventricular elastance to evaluate cardiac performance

Chaos attractors of ventricular elastance to evaluate cardia...

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3rd Japan-Australian Cardiovascular Bioengineering Symposium

关键词： fluctuation E max parameter optimization method ventricular assist device deterministic chaos ventricular elastance cardiac function

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Design and demonstration of pipelined circuits using SFQ logic

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IEICE TRANSACTIONS ON ELECTRONICS 2002年第3期E85C卷 641-644页

作者： Akahori, A Sekiya, A Yamada, T Fujimaki, A Hayakawa, H Nagoya Univ Dept Quantum Engn Nagoya Aichi 4648603 Japan

We have designed the Half Adder (HA) circuit and the Carry Save Serial Adder (CSSA) circuit based on pipeline architecture. Our HA has the structure of a two-stage pipeline and consists of 160 Josephson Junctions (JJs). Our CSSA has the structure of a four-stage pipeline with a feedback loop and consists of 360 JJs. These circuits were fabricated by the NEC standard process. There are two issues which should be considered in the design. One is parameter spreads generated by the fabrication process and the other is leakage currents between the gates. We have introduced a parameter optimization method to deal with the parameter spreads. We have also inserted three stages of JTLs to reduce leakage currents. We have experimentally confirmed the correct operations of these circuits. The obtained bias margins were +/-33.1% for the HA and +/-24.6% for the CSSA.

关键词： SFQ pipeline architecture parameter spread leakage current parameter optimization method

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