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Journal of Integrative Plant Biology 2006年第5期48卷 497-502页

作者： Rui luo chao Wang Daming Zhang State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany the Chinese Academy of Sciences Beijing 100093 China

The localization of 18S ribosomal RNA genes （rDNA） by fluorescence in situ hybridization （FISH） had been performed for some species of Paeonla. However, the pattern of 18S rDNA loci among populations Is Indistinct. In the present study, we localized 18S rDNA loci on meiotic or mitotic chromosomes of six populations of Paeonla obovata Maxim. （Paeonlaceae）. Different numbers of rDNA loci were found with different diploid （2n=10） populations, namely eight （Lushl and Mt. JIuhua populations）, 10 （Mt. Talbal population）, and seven （Mt. Guandl population）, whereas tetraplold （2n=20） populations were all found with 16 loci. Aii rDNA loci were mapped near teiomeres of mitotic chromosomes and there was no chromosome with two loci. The present results show that molecular cytological polymorphlsm exists among P. obovata diploid populations, Indicating that structural variations occurred frequently during the evolutionary history of this species, accompanied with differentiation among populations.

关键词： cytotype fluorescence in situ hybridization (FISH) Paeonia obovata 18S rDNA tetraploid.

EFFECTS OF ENTRAINED AIR MANNER ON CAVITATION DAMAGE

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Journal of Hydrodynamics 2011年第3期23卷 333-338页

作者： WU Jian-hua luo chao College of Water Conservancy and Hydropwer Engineering Hohai University Nanjing 210098 China

Early in 1953 the experiments by Peterka proved that air entrainment has effects on decreasing cavitation damage. This technology has been widely used in the release works of high dams since the inception of air entrainment in the Grand Goulee Dam in 1960. Behavior, mechanism and application of air entrainment for cavitation damage control have been investigated for over half century. However, severe cavitation damage happened due to complex mechanism of air entrainment. The effects of air entrainment are related to many factors, including geometric parameters, hydraulic parameters and entrained air manners. In the present work an experimental set-up for air entrainment was specially designed, the behavior of reducing cavitation damage was experimentally investigated in the three aspects of entrained air pressure, air tube aera and air tube number. The results show that magnitude of reduction of cavitation damage is closely related to the entrained air tube number as well as entrained air pressure, air tube aera, and that the effect through three air tubes is larger than that through single air tube although the entrained air tubes have the same sum of tube aera, that is, 1 ＋ 1 ＋ 1 〉 3. Therefore, it is important to design an effective manner of air entrainment.

关键词： air entrainment air pressure air tube area cavitation damage entrained air manner

A modified domain reduction method for numerical simulation of wave propagation in localized regions

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Earthquake Engineering and Engineering Vibration 2019年第1期18卷 35-52页

作者： luo chao Lou Menglin Gui Guoqing Wang Hao School of Civil Engineering Shijiazhuang Tiedao University Cooperative Innovation Center of Disaster Prevention and Mitigation for Large Infrastructure in Hebei province (Shijiazhuang Tiedao University) State Key Laboratory of Disaster Reduction in Civil Engineering Tongji University School of Architecture and Civil Engineering Jinggangshan University

A modified domain reduction method(MDRM) that introduces damping terms to the original DRM is presented in this paper. To verify the proposed MDRM and compare the computational accuracy of these two methods, a numerical test is designed. The numerical results of the MDRM and DRM are compared using an extended meshed model. The results show that the MDRM significantly improved the computational accuracy of the DRM. Then, the MDRM is compared with two existing conventional methods, namely Liao's transmitting boundary and viscous-spring boundary with Liu's method. The MDRM shows its great advancement in computational accuracy, stability and range of applications. This paper also discusses the influence of boundary location on computational accuracy. It can be concluded that smaller models tend to have larger errors. By introducing two dimensionless parameters, φ_1 and φ_2, the rational distance between the observation point and the MDRM boundary is suggested. When φ_1 >2 or φ_2>13, the relative PGA error can be limited to 5%. In practice, the appropriate model size can be chosen based on these two parameters to achieve desired computational accuracy.

关键词： modified domain reduction method domain reduction method viscous boundary viscous spring boundary transmitting boundary wave propagation

A Chance Constrained Optimal Reserve Scheduling Approach for Economic Dispatch Considering Wind Penetration

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IEEE/CAA Journal of Automatica Sinica 2017年第2期4卷 186-194页

作者： Yufei Tang chao luo Jun Yang Haibo He IEEE Department of Computer & Electrical Engineering and Computer Science and the Institute for Sensing and Embedded Network Systems EngineeringFlorida Atlantic University School of Electrical Engineering Wuhan University Department of Electrical Computer and Biomedical EngineeringUniversity of Rhode Island

The volatile wind power generation brings a full spectrum of problems to power system operation and management, ranging from transient system frequency fluctuation to steady state supply and demand balancing issue. In this paper, a novel wind integrated power system day-ahead economic dispatch model, with the consideration of generation and reserve cost is modelled and investigated. The proposed problem is first formulated as a chance constrained stochastic nonlinear programming U+0028 CCSNLP U+0029, and then transformed into a deterministic nonlinear programming U+0028 NLP U+0029. To tackle this NLP problem, a three-stage framework consists of particle swarm optimization U+0028 PSO U+0029, sequential quadratic programming U+0028 SQP U+0029 and Monte Carlo simulation U+0028 MCS U+0029 is proposed. The PSO is employed to heuristically search the line power flow limits, which are used by the SQP as constraints to solve the NLP problem. Then the solution from SQP is verified on benchmark system by using MCS. Finally, the verified results are feedback to the PSO as fitness value to update the particles. Simulation study on IEEE 30-bus system with wind power penetration is carried out, and the results demonstrate that the proposed dispatch model could be effectively solved by the proposed three-stage approach. © 2017 Chinese Association of Automation.

关键词： Constrained optimization Economics Electric load flow Electric power generation Intelligent systems Monte Carlo methods Nonlinear programming Optimization Particle swarm optimization (PSO) Problem solving Quadratic programming Scheduling Stochastic systems Wind power

Interface structures and mechanical properties of corrugated + flat rolled and traditional rolled Mg/Al clad plates

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Rare Metals 2021年第10期40卷 2947-2955页

作者： Sha Li chao luo Muhammad-Umar Bashir Yi Jia Jian-chao Han Tao Wang College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024China Engineering Research Center of Advanced Metal Composites Forming Technology and Equipment Ministry of EducationTaiyuan 030024China TYUT-UOW Joint Research Center Taiyuan University of TechnologyTaiyuan 030024China

The corrugated + flat rolling(CFR) and traditional rolling(TR) methods were used to prepare Mg/Al clad plates using AZ31 B Mg and 5052 Al plates, and the interface morphologies and mechanical properties of the resulting clad plates were compared. Examination of the microstructures of the plates showed that the TRed Mg/Al clad plate presented a straight interface, while a corrugated interface containing fractured intermetallic particulates was observed for the CFRed plate due to the inhomogeneous strain induced by the corrugated roller. During the CFR process, the corrugated roller can accelerate the rupture of the substrate work-hardening layers and facilitate the mutual extrusion of fresh metals to enhance the interface bonding. Compared with the traditional basal texture of the Mg alloy, the CFR process can change the texture morphology, thereby enhancing the plastic deformation ability of the Mg plate. Tensile tests showed that the CFRed Mg/Al clad plate exhibited a higher ultimate tensile strength(UTS, 316 MPa), which was~ 8% higher than that of the TRed plate(293 MPa). In addition, the bending curve of the CFRed clad plate was smooth and there was no stress sudden drop phenomenon in the bending process. The higher UTS and excellent bending properties of the CFRed clad plate could be attributed to the enhanced coordinated deformation ability of the substrates induced by the corrugated interface, grain refinement, and the change in the Mg alloy texture morphology.

关键词： Mg/Al clad plate Corrugated+flat rolling Traditional rolling Interface morphologies Mechanical properties

Two-dimensional materials-decorated microfiber devices for pulse generation and shaping in fiber lasers

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Chinese Physics B 2018年第9期27卷 63-72页

作者： Zhi-chao luo＊ Meng Liu Ai-Ping luo and Wen-Cheng Xu Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and Devices ＆ Guangzhou Key Laboratory for Special Fiber Pbotonic Devices and Applications South China Normal UniversityGuangzhou 510006China

Two-dimensional（2D） materials have been regarded as a promising nonlinear optical medium for fabricating versatile optical and optoelectronic devices. Among the various photonic applications, the employment of 2D materials as nonlinear optical devices such as saturable absorbers for ultrashort pulse generation and shaping in ultrafast lasers is one of the most striking aspects in recent years. In this paper, we review the recent progress of 2D materials based pulse generation and soliton shaping in ultrafast fiber lasers, and particularly in the context of 2D materials-decorated microfiber photonic devices. The fabrication of 2D materials-decorated microfiber photonic devices, high performance mode-locked pulse generation, and the nonlinear soliton dynamics based on pulse shaping method are discussed. Finally, the challenges and the perspective of the 2D materials-based photonic devices as well as their applications are also discussed.

关键词： two-dimensional materials microfiber soliton dynamics fiber lasers

Graphene-decorated microfiber knot as a broadband resonator for ultrahigh-repetition-rate pulse fiber lasers

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Photonics Research 2018年第10期6卷 I0003-I0009页

作者： MENG Liu RUI TANG AI-PING luo WEN-CHENG Xu ZHI-chao luo Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and Devices & Guangzhou Key Laboratory for Special Fiber Photonic Devices and Applications South China Normal University Guangzhou 510006 China Guangdong Provincial Engineenng Technology Research Center for Microstructured Functional Fibers and Devices South China Normal University Guangzhou 510006 China

Searching for an ultrahigh-repetition-rate pulse on the order of hundreds of gigahertz(GHz) is still a challenging task in the ultrafast laser community. Recently, high-quality silicon/silica-based resonators were exploited to generate a high-repetition-rate pulse based on the filter-driven four-wave mixing effect in fiber lasers. However,despite their great performance, the silicon/silica-based resonators still have some drawbacks, such as single waveband operation and low coupling efficiency between the fiber and resonators. To overcome these drawbacks,herein we proposed an all-fiber broadband resonator fabricated by depositing the graphene onto a microfiber knot. As a proof-of-concept experiment, the graphene-deposited broadband microfiber knot resonator(MKR)was applied to Er-and Yb-doped fiber lasers operating at two different wavebands, respectively, to efficiently generate hundreds-of-GHz-repetition-rate pulses. Such a graphene-deposited broadband MKR could open some new applications in ultrafast laser technology, broadband optical frequency comb generation, and other related fields of photonics.

关键词：重复频率脉冲激光技术发展现状通讯技术

Tissue Segmentation in Nasopharyngeal CT Images Using Two-Stage Learning

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Computers, Materials & Continua 2020年第11期65卷 1771-1780页

作者： Yong luo Xiaojie Li chao luo Feng Wang Xi Wu Imran Mumtaz Cheng Yi West China Hospital Sichuan UniversityChengdu610000China Chengdu University of Information Technology Chengdu610000China University of Agriculture Faisalabad38000Pakistan

Tissue segmentation is a fundamental and important task in nasopharyngeal images ***,it is a challenging task to accurately and quickly segment various tissues in the nasopharynx region due to the small difference in gray value between tissues in the nasopharyngeal image and the complexity of the tissue *** this paper,we propose a novel tissue segmentation approach based on a two-stage learning framework and *** the proposed methodology,the network consists of two segmentation *** first module performs rough segmentation and the second module performs accurate *** the training time and the limitation of computing resources,the structure of the second module is simpler and the number of network layers is *** addition,our segmentation module is based on U-Net and incorporates a skip structure,which can make full use of the original features of the data and avoid feature *** evaluated our proposed method on the nasopharyngeal dataset provided by West China Hospital of Sichuan *** experimental results show that the proposed method is superior to many standard segmentation structures and the recently proposed nasopharyngeal tissue segmentation method,and can be easily generalized across different tissue types in various organs.

关键词： Tissue segmentation deep learning two-stage network convolutional neural network

Intelligent control of mode-locked femtosecond pulses by time-stretch-assisted real-time spectral analysis

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Light(Science & Applications) 2020年第1期9卷 1881-1888页

作者： Guoqing Pu Lilin Yi Li Zhang chao luo Zhaohui Li Weisheng Hu State Key Lab of Advanced Communication Systems and Networks Shanghai Institute for Advanced Communication and Data ScienceShanghai Jiao Tong UniversityShanghai 200240China Sun Yat-sen University/Southern Marine Science and Engineering Guangdong Laboratory ZhuhaiChina

Mode-locked fiber lasers based on nonlinear polarization evolution can generate femtosecond pulses with different pulse widths and rich spectral distributions for versatile applications through polarization ***,a precise and repeatable location of a specific pulsation regime is extremely ***,by using fast spectral analysis based on a time-stretched dispersion Fourier transform as the spectral discrimination criterion,along with an intelligent polarization search algorithm,for the first time,we achieved real-time control of the spectral width and shape of mode-locked femtosecond pulses;the spectral width can be tuned from 10 to 40 nm with a resolution of ~1.47 nm,and the spectral shape can be programmed to be hyperbolic secant or ***,we reveal the complex,repeatable transition dynamics of the spectrum broadening of femtosecond pulses,including five middle phases,which provides deep insight into ultrashort pulse formation that cannot be observed with traditional mode-locked lasers.

关键词： polarization tuning spectral

Three dimensional phase-field simulation for non-isothermal binary alloy solidification: Comparison with LKT theory

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China Foundry 2023年第6期20卷 545-552页

作者： Jun Wu Ting-yi Liu Gui-chao Hu Rong Ma Xiao-peng Zhang Yu-fei Li chao luo Institute of Materials China Academy of Engineering PhysicsJiangyou 621907SichuanChina

Using the advanced algorithm combining parallel computing,adaptive mesh re-griding and multigrid methods,quantitative 3D phase-field simulations of non-isothermal solidification of binary alloy were carried *** 3D phase-field simulation results were compared with the analytical LKT(Lipton,Kurz and Trivedi)*** comparison,the simulation and analytical results for 2D cases were also *** 3D phase-field simulation results support the transport portion of the LKT ***,the tip radius and tip velocity predicted by the simulations are not in good agreement with the LKT theory over the whole range of *** stability parameter calculated from phase-field simulations varies significantly with the Peclet number,indicating that the stability criterion,which assumes that the stability parameter is constant,is invalid.

关键词： 3D phase-field non-isothermal solidification free dendritic growth