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Chinese Physics B 2021年第6期30卷 176-187页

作者： Lei Jiang Li Lai Tao Yu Maokang luo College of Mathematics Sichuan UniversityChengdu 610064China College of Aeronautics and Astronautics Sichuan UniversityChengdu 610064China

The collective behaviors of two coupled harmonic oscillators with dichotomous fluctuating frequency are investigated,including stability, synchronization, and stochastic resonance(SR). First, the synchronization condition of the system is obtained. When this condition is satisfied, the mean-field behavior is consistent with any single particle behavior in the system. On this basis, the stability condition and the exact steady-state solution of the system are derived. Comparative analysis shows that, the stability condition is stronger than the synchronization condition, that is to say, when the stability condition is satisfied, the system is both synchronous and stable. Simulation analysis indicates that increasing the coupling strength will reduce the synchronization time. In weak coupling region, there is an optimal coupling strength that maximizes the output amplitude gain(OAG), thus the coupling-induced SR behavior occurs. In strong coupling region, the two particles are bounded as a whole, so that the coupling effect gradually disappears.

关键词： coupled harmonic oscillators dichotomous fluctuating frequency synchronization stability stochastic resonance

Modeling of acute cadmium toxicity in solution to barley root elongation using biotic ligand model theory

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Journal of Environmental Sciences 2016年第4期28卷 112-118页

作者： Xuedong Wang Mingyan Wu Jingxing Ma Xiaolin Chen luo Hua The Key Lab of Resource Environment and GIS College of Resource Environment and TourismCapital Normal University

Protons（H^＋）as well as different major and trace elements may inhibit cadmium（Cd）uptake in aquatic organisms and thus alleviate Cd ***,little is known about such interactions in soil *** this study,the independent effects of the cations calcium（Ca^2＋）,magnesium（Mg^2＋）,potassium（K^＋）,H^＋ and zinc（Zn^2＋）on Cd toxicity were investigated with 5-day long barley root elongation tests in nutrient *** tested concentrations of selected cations and trace metal ions were based on the ranges that occur naturally in soil pore *** toxicity of Cd decreased with increasing activity of Ca^2＋,Mg^2＋,H^＋and Zn^2＋,but not K^＋.Accordingly,conditional binding constants were obtained for the binding of Cd^2＋,Ca^2＋,Mg^2＋,H^＋,and Zn^2＋ with the binding ligand：log K（CdBL）5.19,logK（CaBL）2.87,logK（MgBL）2.98,logK（HBL）5.13 and logK（ZnBL）5.42,***,it was calculated that on average 29% of the biotic ligand sites needed to be occupied by Cd to induce a 50% decrease in root *** the estimated constants,a biotic ligand model was successfully developed to predict the Cd toxicity to barley root elongation as a function of solution *** feasibility and accuracy of its application for predicting Cd toxicity in soils were discussed.

关键词： Cadmium Biotic ligand model (BLM) Toxicity Barley

Experimental Study of Nd^(3+):KGd(WO_(4))_(2) Laser Pumped by Laser Diode

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Chinese Physics Letters 1996年第3期13卷 178-181页

作者： ZHAO Ting-jie TU Chao-yang luo Zun-du Fufian Institute of Research on the Structure of Matter Chinese Academy of SciencesFuzhou 350002

This paper presents the cw output characteristics of Nd^(3+):KGd(WO_(4))_(2)(KGW)laser crystal with different NcP+concentration grown in our *** laser output at 1.067 μm of KGW crystal(3×3×6 mm)was obtained to be 6... 详细信息

关键词： pumped laser diode

An Encoder with Speed over 40Gbps for RC LDPC Codes with Rates Up to 0.96

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Chinese Journal of Electronics 2016年第5期25卷 921-927页

作者： HE Zhiyong ZHAO Qiang XU Hushan CUI Wenjuan luo Yuxi Institute of Modern Physics Chinese Academy of Sciences

We propose a class of Rate-compatible(RC) Low-density parity-check(LDPC) codes with a very wide range of code rates. To widen the range of rates, we have developed an optimal transmission scheme to push the upper bound of code rates to 0.96. Characterized by a parity check matrix in a dual-diagonal form, the proposed RC LDPC code can be encoded in linear time. Constructed from shifted identity sub-matrices, the proposed codes are particularly well-suited for the high-speed implementation of parallel encoders. Furthermore, the encoder can be implemented efficiently with several left circular shifters and XOR gates. To maximize the encoding speed, we have proposed a q-parallel encoder architecture, where q is the size of each sub-matrix. The implementation results into Field programmable gate array(FPGA) devices indicate that a72-parallel encoder for the proposed RC LDPC code with a code rate from 0.5 to 0.96 is capable of reaching a speed of 42 Gigabits per second(Gbps) using a clock frequency of 300 MHz.

关键词： Low-density parity-check codes(LDPC) High-speed encoder Field programmable gate array(FPGA) implementation

A Quantitative Process-Based Inventory Study on Material Embodied Carbon Emissions of Residential, Office, and Commercial Buildings in China

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Journal of Thermal Science 2019年第6期28卷 1236-1251页

作者： luo Zhixing CANG Yujie ZHANG Nan YANG Liu LIU Jiaping State Key Laboratory of Green Building in Western China Xi'an University of Architecture and TechnologyShaanxi 710055China College of Architecture Xi'an University of Architecture and TechnologyShaanxi 710055China

Studies on building carbon emissions focus mainly on the materialization phase of life cycle, as carbon emissions in this stage is intensive and high. This paper proposes a simplified model to calculate embodied carbon emissions in building design stage by conducting a process-based inventory analysis of carbon emissions from materials used in 129 residential buildings, 41 office buildings, and 21 commercial buildings during materialization phase. The results indicate that average carbon emissions per unit area from building materials used in residential buildings, office buildings, and commercial buildings are 514.66 kgCO2 e/m2, 533.69 kg CO2 e/m2 and 494.19 kgCO2 e/m2, respectively. Besides, ten kinds of building materials(namely, steel, commercial concrete, wall building materials, mortar, copper core cables, architectural ceramics, PVC pipes, thermal insulation materials, doors and windows, and water paint) constitute 99% of total carbon emissions in all three types of buildings. These materials are major carbon emissions sources in materialization phase. Thus, embodied carbon emissions can be significantly reduced by limiting the amount of these materials in architectural design as well as by using environmental friendly materials.

关键词： embodied carbon emissions life cycle analysis materialization phase building material

Thermal–structure coupling analysis and multi-objective optimization of motor rotor in MSPMSM

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Chinese Journal of Aeronautics 2019年第7期32卷 1733-1747页

作者： Luxin ZHAI Jinji SUN Xin MA Weitao HAN Xiaosan luo School of Instrumentation Science&Opto-electronics Engineering Beihang UniversityBeijing100083China CRRC Qingdao Sifang Co. Ltd.Qingdao266111China

With the high speed, the rotor of magnetically suspended permanent magnet synchronous motor(MSPMSM) suffers great thermal stress and mechanical stress resulting from the temperature rise problem caused by rotor losses, which leads to instability and *** this paper, the mechanical–temperature field coupling analysis is conducted to analyze the relationship between the temperature field and structure, and multi-objective optimization of a rotor is performed to improve the design reliability and efficiency. Firstly, the temperature field is calculated by the 2 D finite element model of MSPMSM and the method of applying the 2 D temperature result to the 3 D finite element model of the motor rotor equivalently is proposed. Then the thermal–structure coupling analysis is processed through mathematic method and finite element method(FEM),in which the 3 D finite element model is established precisely in a way and approaches the practical operation state further. Moreover, the impact produced by the temperature and structure on the mechanical strength is analyzed in detail. Finally, the optimization mathematical model of the motor rotor is established with Sequential Quadratic Programming-NLPQL selected in the optimization scheme. Through optimization, the strength of the components in the motor rotor increases obviously and satisfies the design requirement, which to a great extend enhances the service life of the MSPMSM rotor.

关键词： FEM MSPMSM Multi-objective optimization Thermal stress Thermal–structure coupling analysis

Rigorous design and economic optimization of reactive distillation column considering real liquid hold-up and hydraulic conditions of industrial device

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CHINESE JOURNAL OF CHEMICAL ENGINEERING 2024年第12期76卷 211-226页

作者： Du, Yuchang luo, Yiqing Yang, Peilin Jia, Shengkun Yuan, Xigang Tianjin Univ Chem Engn Res Ctr Tianjin 300354 Peoples R China Tianjin Univ Sch Chem Engn & Technol Tianjin 300354 Peoples R China Tianjin Univ State Key Lab Chem Engn Tianjin 300354 Peoples R China

The liquid hold-up in a reactive distillation (RD) column not only has a significant impact on the extent of reactions, but also affects the pressure drop and hydraulic conditions in the column. Therefore, the liquid hold-up would be a critical design factor for RD columns. However, the existing design methods for RD columns typically neglect the influence of considerable amount of liquid hold-up in downcomers owing to the difficulties of solving a large-scale nonlinear model system by considering downcomer hydraulics, resulting in significant deviations from actual situation and even operation infeasibility of the designed column. In this paper, a pseudo-transient (PT) RD model based on equilibrium model considering tray hydraulics was established for rigorous simulation and optimization of RD plate columns considering the liquid hold-up both in downcomers and column trays, and a steady-state optimization algorithm assisted by the PT model was adopted to robustly solve the optimization problem. The optimization results of either ethylene glycol RD or methyl acetate RD demonstrated that assuming all the liquid hold-up of a stage belonged to the tray will cause significant deviations in the column diameter, weir height, and the number of stages, which leads to not meeting the separation requirements and even operation hydraulic infeasibility. The rigorous model proposed in this study which considers the liquid hold-up both on trays and in downcomers as well as hydraulic constraints can be applied to systematically design industrial RD plate columns to simultaneously obtain optimal operating variables and equipment structure variables. (c) 2024 The Chemical Industry and Engineering Society of China, and Chemical Industry Press Co., Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

关键词： Reactive distillation Liquid hold-up Downcomer Tray hydraulics Pseudo-transient modeling method

ARAP++:an extension of the local/global approach to mesh parameterization

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Frontiers of Information Technology & Electronic Engineering 2016年第6期17卷 501-515页

作者： Zhao WANG Zhong-xuan luo Jie-lin ZHANG Emil SAUCAN School of Mathematical Sciences Dalian University of TechnologyDalian 116024China School of Software Dalian University of TechnologyDalian 116620China Max Planck Institute for Mathematics in the Sciences Leipzig 70569Germany

Mesh parameterization is one of the fundamental operations in computer graphics(CG) and computeraided design(CAD). In this paper, we propose a novel local/global parameterization approach, ARAP++, for singleand multi-boundary triangular meshes. It is an extension of the as-rigid-as-possible(ARAP) approach, which stitches together 1-ring patches instead of individual triangles. To optimize the spring energy, we introduce a linear iterative scheme which employs convex combination weights and a fitting Jacobian matrix corresponding to a prescribed family of transformations. Our algorithm is simple, efficient, and robust. The geometric properties(angle and area)of the original model can also be preserved by appropriately prescribing the singular values of the fitting matrix. To reduce the area and stretch distortions for high-curvature models, a stretch operator is introduced. Numerical results demonstrate that ARAP++ outperforms several state-of-the-art methods in terms of controlling the distortions of angle, area, and stretch. Furthermore, it achieves a better visualization performance for several applications, such as texture mapping and surface remeshing.

关键词： Mesh parameterization Convex combination weights Stretch operator Jacobian matrix

A comprehensive simulation of weak-light phase-locking for space-borne gravitational wave antenna

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Science China(Technological Sciences) 2016年第5期59卷 730-737页

作者： DONG YuHui LIU HeShan luo ZiRen LI YuQiong JIN Gang National Microgravity Laboratory (NML) Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100190 China QUEST Centre of Quantum Engineering and Space-Time Research Leibniz Universitat Hannover Hannover 30167 Germany Max-Planck-Institude for Gravitational Physics (Albert Einstein Institute) Hannover 30167 Germany

A comprehensive simulation was performed to better understand the impacts and effects of the additional technical noises on weak-light phase-locking for LISA. The result showed that the phase of the slave laser tracked well with the received transmitting light under different noise level, and the locking precision was limited by the phase readout noise when the laser frequency noise and clock jitter noise were removed. This result was then confirmed by a benchtop experimental test. The required LISA noise floor was recovered from the simulation which proved the validity of the simulation program. In order to convert the noise function into real time data with random characteristics, an algorism based on Fourier transform was also invented.

关键词： weak-light phase-locking gravitational wave detection heterodyne laser interferometer

Revealing nonclassicality via s-ordered phase-space distribution

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Science China(Physics,Mechanics & Astronomy) 2022年第11期65卷 90-96页

作者： Yue Zhang Shuheng Liu Boxuan Jing Qiongyi He Shunlong luo State Key Laboratory of Mesoscopic Physics School of PhysicsFrontiers Science Center for Nano-optoelectronicsPeking UniversityBeijing100871China Beijing Academy of Quantum Information Sciences Beijing100193China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan030006China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing100049China

Nonclassical states play a crucial role in both theoretical and experimental investigations of quantum optics, and there is a wide interest in characterization and quantification of nonclassicality. By exploiting the freedom of the parameter s in the s-ordered phase-space distribution introduced by Cahill and Glauber [Phys. Rev. 177, 1882(1969)], we develop a method to reveal and quantify optical nonclassicality via the divided difference of the s-ordered phase-space distribution. Our approach yields naturally a family of quantifiers of optical nonclassicality, which have many desirable properties such as convexity and monotonicity under the Gaussian noise channels. The quantifiers are illustrated by evaluating nonclassicality of several typical states. Two simple and convenient criteria for nonclassicality are established, which in particular certify all nonclassical Gaussian states.

关键词： nonclassicality s-ordered phase-space distribution Gaussian states Gaussian noise channels

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