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The Initial-Boundary-Value Problems for the Hirota Equation on the Half-line

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Chinese Annals of Mathematics,Series B 2020年第1期41卷 117-132页

作者： lin huang School of Science Hangzhou Dianzi UniversityHangzhou 310018China School of Mathematical Sciences Fudan UniversityShanghai 200433China

An initial boundary-value problem for the Hirota equation on the half-line,00, is analysed by expressing the solution q(x, t) in terms of the solution of a matrix Riemann-Hilbert(RH) problem in the complex k-plane. This RH problem has explicit(x, t) dependence and it involves certain functions of k referred to as the spectral functions. Some of these functions are defined in terms of the initial condition q(x,0) = q0(x), while the remaining spectral functions are defined in terms of the boundary values q(0, t) = g0(t), qx(0, t) = g1(t) and qxx(0, t) = g2(t). The spectral functions satisfy an algebraic global relation which characterizes, say, g2(t) in terms of {q0(x), g0(t), g1(t)}.The spectral functions are not independent, but related by a compatibility condition, the so-called global relation.

关键词： Hirota equation Riemann-Hilbert problem Initial-boundary value problem Global relation

Energy-efficiency maximization for fixed-wing UAV-enabled relay network with circular trajectory

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Chinese Journal of Aeronautics 2022年第9期35卷 71-80页

作者： Chenxiao XIE Xin-lin huang Department of Information and Communication Engineering Tongji UniversityShanghai 201804China

With the development of Unmanned Aerial Vehicles(UAVs), the applications of UAVs have been extensively explored. In the field of wireless communications, the relay nodes are often used to extend network coverage. However, traditional fixed ground relays cannot be flexibly deployed due to their low heights and fixed locations. Hence, deploying UAV as relay node is a promising solution and has become a research hotspot. In this paper, we consider an UAVenabled relaying network in which a fixed-wing UAV is deployed between the Base Station(BS)and Ground Users(GUs). We study the energy-efficiency gap between the link “BS-UAV-GUs”and the link “BS-GUs”, and jointly optimize UAV relay transmission power and flight radius to achieve the highest energy-efficiency. Firstly, the UAV/BS-GUs channels models and the UAV energy consumption model are built. Secondly, the optimization objective function is formulated to maximize the energy-efficiency gap. Then, the solution of the optimization problem is divided into a two-step iteration process, in which the UAV relay transmission power and flight radius are adjusted to maximize the energy-efficiency gap. Finally, the experimental results under different simulation scenarios(such as cities, forests, deserts, oceans, etc.) are shown to illustrate the effectiveness of the proposed algorithm. The results show that the proposed algorithm can always find the optimal UAV relay transmission power and flight radius settings, and achieve the largest energy-efficiency gap. The convergency speed of the proposed algorithm is fast, and can obtain the optimal solution within only a few iterations.

关键词： Circular trajectory Energy efficiency Fixed wing UAV Power allocation UAV relay

Effects of compressibility on the Rayleigh-Taylor instability in Z-pinch implosions

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核聚变与等离子体物理 2006年第2期26卷 87-94页

作者： huang lin JIAN Guang-de Southwestern Institute of Physics Chengdu 61004 1

The effects of compressibility on the Rayleigh-Taylor instability in Z-pinch implosion plasmas are investigated by means of simple slab *** linear mode equation,which includes main steady-state quantities and their gradients,is *** solutions are *** incompressible fluid result is also *** results indicate that the linear growth rate of the Rayleigh-Taylor instability for the compressible magnetohydrodynamic fluid is far larger than one in the incompressible ***,the compressible systems are all more unstable than the incompressible ones.

关键词： Z-pinch Rayleigh-Taylor instability Compressibility Growth rate.

Subunit Characteristics of Pig Pancreas Ferritin Revealed by MALDI-TOF MS and RP-HPLC

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Chemical Research in Chinese Universities 2008年第5期24卷 550-556页

作者： huang lin lin Zhi-cao lin Qing LUO Lian-zhong huang He-qing Key Laboratory of the MOD for Cell Biology and Tumor Cell Engineering School of Life Sciences State Key Laboratory of Physical Chemistry of Solid Surface Key Laboratory of Chemical Biology of Fujian Province College Chemistry ＆ Chemical Engineering Xiamen University Xiamen 361005 P R. China

Pig pancreas ferritin（PPF） was purified by ultra-centrifugation, ion-exchange chromatography, and native gradient polyacrylamide gel electrophoresis（PAGENG）. Sodium dodecyl sulfate（SDS）-PAGE indicates that PPF consists of two subunit types, namely, H（21000） and L（19000） subunits, and its core shows an average element composition of 1698 Fe3＋ and 179 phosphate molecules within the hollow shell, giving a 9.5：1 ratio of Fe3＋ to phosphate. An off line approach combining reversed-phase high-performance liquid chromatography（RP-HPLC） with matrix-assisted laser desorption ionization time of flight mass spectrometry（MALDI-TOF MS） made the decomposition of PPF shell into H and L subunits for the analysis of mass spectrometry（MS）, giving molecular weights of both H（21014.4） and L（18319.9） subunits. Both subunit types were further identified by an approach combining peptide mass fingerprint（PMF） with database search. A ratio of 1H to 2L subunits in PPF was determined by SDS-PAGE, RP-HPLC, and MALDI-TOF MS, respectively. It is well known that the non-covalent interaction of L-L or H-L subunits is stronger than that of H-H subunits in PPF, which may be further used to explain the unclear physiological function between H and L subunits in PPF.

关键词： Ferritin Pig pancreas Subunit structure Proteomic MALDI-TOF MS RP-HPLC

NUMERICAL SIMULATION OF PROPAGATION AND BREAKING PROCESSES OF A FOCUSED WAVES GROUP

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Journal of Hydrodynamics 2012年第3期24卷 399-409页

作者： huang Zong-liu lin Peng-zhi State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065China

A two-dimensional numerical wave flume is developed to study the focused waves group propagation and the consequent breaking processes. The numerical model is based on the Reynolds-Averaged Navier-Stokes （PANS） equations, with the standard k - c turbulence model to simulate the turbulence effects. To track the complicated and broken free-surface, the Volume Of Fluid （VOF） method is employed. The numerical model combines the ＂Partial Cell Treatment （PCT）＂ method with the ＂Locally Relative Stationary （LRS）＂ concept to treat the moving wave paddle so that various waves can be generated directly in a fixed Cartesian grid system. The theoretical results of the linear and nonlinear waves are used to validate the numerical wave flume firstly, and then a plunging breaking wave created by a focused waves group is simulated. The numerical results are compared to the experimental data and other simulation results, with very good agreements. The turbulence intensity, the flow field and the energy dissipation in the breaking processes are analyzed based on the numerical results. It is shown that the present numerical model is efficient and accurate for studying the waves group generation, the waves packet propagation, and the wave breaking processes.

关键词： focused waves group plunging breaking Volume Of Fluid (VOF) k - ε turbulence model irregular wave maker

H_∞ CONTROL OF NETWORKED MULTI-AGENT SYSTEMS

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Journal of Systems Science & Complexity 2009年第1期22卷 35-48页

作者： Zhongkui LI Zhisheng DUAN lin huang State Key Lab for Turbulence and Complex Systems and Department of Mechanics and Aerospace Engineering College of Engineering Peking University Beijing 100871 China.

This paper concerns the disturbance rejection problem arising in the coordination control of a group of autonomous agents subject to external disturbances. The agent network is said to possess a desired level of disturbance rejection, if the H∞ norm of its transfer function matrix from the disturbance to the controlled output is satisfactorily small. Undirected graph is used to represent the information flow topology among agents. It is shown that the disturbance rejection problem of an agent network can be solved by analyzing the H∞ control problem of a set of independent systems whose dimensions are equal to that of a single node. An interesting result is that the disturbance rejection ability of the whole agent network coupled via feedback of merely relative measurements between agents will never be better than that of an isolated agent. To improve this, local feedback injections are applied to a small fraction of tile agents in the network. Some criteria for possible performance improvement are derived in terms of linear matrix inequalities. Finally, extensions to the case when communication time delays exist are also discussed.

关键词： Coordination control graph theory H∞ control linear matrix inequality (LMI) pinning control.

A Hybrid Dissipative Trapped Electron ITG Mode

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Chinese Physics Letters 1995年第12期12卷 743-746页

作者： BAI lin QIU Xiaoming huang lin Southwestern Institute of Physics P.O.Box 432Chengdu 610041

A simple model for theηi-mode taking account of the dissipative trapped electron effect,which is described by means of the well-known formula of the nonadiabatic electron response,in a sheared slab geometry is *** predicts the existence of a hybrid dissipative trapped electron ion temperature gradient(ITG)*** conclusion is in agreement with the observation in the latest simulated tokamak experiment on the Columbia linear Machine.

关键词： dissipative Electron conclusion

Thermoacoustic imaging:From single-element scanning to portable and array-based imaging

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Journal of Electronic Science and Technology 2023年第3期21卷 1-20页

作者： Yi-Jie huang Qi-Kai-Yu Feng lin huang School of Electronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu610054China Zhangjiang Laboratory Shanghai201204China

The microwave-induced thermoacoustic imaging(TAI)technology has both the advantages of high contrast of microwave imaging and high resolution of ultrasound imaging(UI),so it has carried out exploratory application research in various areas,such as the early detection of breast tumors and cerebrovascular ***,the microwave generator used in the traditional TAI technology is huge and expensive,and the temporal resolution is also too low due to the single-element scanning ***,it is difficult to meet the needs of clinical *** this paper,the iterative process and the analysis of related application scenarios from single-element scanning to portable and array-based TAI,such as the miniaturized microwave generator,handheld antenna,multi-channel data acquisition,and UI/TAI􀀁dual-modality imaging,are reviewed,and the future trends of this technology are *** review helps researchers in the field of TAI learn the technological development process and future *** also deepens clinicians’understanding of TAI so as to put forward more application requirements.

关键词： Array-based Portable Single-element scanning Thermoacoustic imaging(TAI)

Suppression of Rayleigh-Taylor instability by gyroviscosity and sheared axial flow in imploding plasma pinches

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核聚变与等离子体物理 2007年第2期27卷 87-94页

作者： huang lin JIAN Guang-de QIU Xiao-ming Southwestern In stitute of Physics Chengdu 610041

The synergistic stabilizing effect of gyroviscosity and sheared axial flow on the Rayleigh-Taylor instability in Z-pinch implosions is studied by means of the incompressible viscid magneto-hydrodynamic *** gyroviscosity(or finite Larmor radius) effects are introduced in the momentum equation through an anisotropic ion stress *** relation with the effect of a density discontinuity is *** results indicate that the short-wavelength modes of the Rayleigh-Taylor instability are easily stabilized by the gyroviscosity *** long wavelength modes are stabilized by the sufficient sheared axial ***,the synergistic effects of the finite Larmor radius and sheared axial flow can heavily mitigate the Rayleigh-Taylor *** synergistic effect can compress the Rayleigh-Taylor instability to a narrow wave number *** with a sufficient gyroviscosity and large enough flow velocity,the synergistic effect can completely suppressed the Rayleigh-Taylor instability in whole wave number region.

关键词：雷利-泰勒不稳定性回转粘性内向爆炸等离子体箍缩增敏作用有限拉莫尔旋进半径增长比率