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Chinese Optics Letters 2019年第11期17卷 11-16页

作者： N.Othman K.G.Tay N.S.Mohd Shah R.Talib H.Pakarzadeh N.A.Cholan Faculty of Electrical and Electronic Engineering Universiti Tun Hussein Onn Malaysia86400 Batu PahatJohorMalaysia Faculty of Engineering Technology Universiti Tun Hussein Onn Malaysia84600 PagohJohorMalaysia Department of Physics Shiraz University of TechnologyShirazIran

The influence of the fourth-order dispersion coefficient on the behavior of parametric gain and saturation power of a one-pump fiber optical parametric amplifier over a signal wavelength span in the presence of fiber random dispersion fluctuations was investigated. The output signal power for the parametric gain calculation was obtained by numerically solving the three-coupled amplitude equations. Based on the calculations of the parametric gain over a variation of the signal wavelength, it is found that the saturation power behavior is dependent on the behavior of parametric gain. The manipulations of signal wavelength and the fourth-order dispersion coefficient changed the phase-matching condition, thereby affecting the resulting parametric gain and saturation power.

关键词： parametric dispersion coefficient

Lump and lump-soliton interaction solutions for an integrable variable coefficient Kadomtsev-Petviashvili equation

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Communications in Theoretical Physics 2020年第3期72卷 1-6页

作者： Xin Wang Jina Li Lei Wang Jiao Wei Bowen Guo College of Science Zhongyuan University of TechnologyZhengzhouHenan450007China School of Mathematics and Physics North China Electric Power UniversityBeijing102206China School of Mathematics and Statistics Zhengzhou University100 Kexue RoadZhengzhouHenan450001China

For a variable coefficient Kadomtsev-Petviashvili(KP)equation the Lax pair as well as conjugate Lax pair are derived from the Painleve analysis.The N-fold binary Darboux transformation is presented in a compact form.As an application,the multi-lump,higher-order lump and general lump-soliton interaction solutions for the variable coefficient KP equation are obtained.Typical lump structures with amplitudes exponentially decaying to zero as the time tends to infinity and interactions between one lump and one soliton are shown.

关键词： variable coefficient KP equation binary Darboux transformation lump solution lump-soliton interaction solution

Effect of adhesive type on the sensitivity coefficient of FBG sensor bonded on the surface of CFRP

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Optoelectronics Letters 2019年第4期15卷 264-268页

作者：田恒刘东光王艳苹王庆林 Department of Chemical and Chemical Engineering Hefei Normal University Hefei 230601 China School of Materials Science and Engineering Hefei University of Technology Hefei 230009 China

In this paper, the effects of three types of commonly used adhesives were studied via experiment and simulation. The results show that the strain sensitivity of fiber Bragg grating(FBG) sensor is about 1.201 pm/με and the effects of three adhesives of epoxy resin, AB glue and 502 glue with the same thickness and length on sensitivity coefficients of FBG sensors are 99.20%, 93.80% and 96.50%, respectively. Finally, the sensitivity coefficient of the simulated FBG sensor is the same as the test result by ANSYS modeling.

关键词： CFRP fiber Bragg grating(FBG) sensitivity coefficient

Effect of Friction coefficient on Deep Drawing of 6A16 Aluminum Alloy for Automobile Body

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Journal of Wuhan University of Technology(Materials Science) 2020年第1期35卷 208-214页

作者：刘钊扬熊柏青 LI Xiwu YAN Lizhen LI Zhihui ZHANG Yongan LIU Hongwei State Key Laboratory of Nonferrous Metals and Processes GRIMAT Engineering Institute Co.Ltd.Beijing 101407China GRINM Engineering Institute Co. LTD.Beijing 101407China General Research Institute for Nonferrous Metal Beijing 100088China

Based on the ABAQUS/Explicit finite element method,the forming force changing trend of deep drawing test for 6A16 aluminum alloy plate after pre-aging and storage at room temperature for one month was simulated under friction coefficient ranging from 0 to 0.22.The lubricants selected for the tests were mechanical oil,butter and dry film lubricant,and the friction coefficient of these lubricants were 0.05,0.10 and 0.15,respectively.Microstructural evolution of 6 A16 aluminum alloy plate during drawing forming was investigated by OM,SEM and EBSD.The results showed that,with the increase of friction coefficient,the stress,strain and deformation degree in deformation zone increased,while the grain size in deformation zone decreased.Thus,the hardness of the cup-typed component increased with the increase of friction coefficient.Butter-lubricated cups had the highest tensile strength and yield strength after paint-bake cycle.The combination of simulation results and microstructure analysis of 6A16 aluminum alloy plate after drawing forming indicates that the appropriate lubricant is butter.

关键词： finite element method 6A16 aluminum alloys deep drawing test friction coefficient

Feature Screening for Ultrahigh-dimensional Censored Data with Varying coefficient Single-index Model

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Acta Mathematicae Applicatae Sinica 2019年第4期35卷 845-861页

作者： Yi LIU School of Mathematical Sciences Ocean University of China

In this paper, we study the sure independence screening of ultrahigh-dimensional censored data with varying coefficient single-index model. This general model framework covers a large number of commonly used survival models. The property that the proposed method is not derived for a specific model is appealing in ultrahigh dimensional regressions, as it is difficult to specify a correct model for ultrahigh dimensional predictors.Once the assuming data generating process does not meet the actual one, the screening method based on the model will be problematic. We establish the sure screening property and consistency in ranking property of the proposed method. Simulations are conducted to study the finite sample performances, and the results demonstrate that the proposed method is competitive compared with the existing methods. We also illustrate the results via the analysis of data from The National Alzheimers Coordinating Center(NACC).

关键词： censored data consistency in ranking property feature selection high-dimensional data sure screening property varying coefficient single-index model

Variable coefficient KdV Equation for Amplitude of Nonlinear Solitary Rossby Waves in a Sort of Time-Dependent Zonal Flow

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高原气象 2011年第2期30卷 349-354页

作者： DA Chao-jiu SUN Shu-peng SONG Jian YANG Lian-gui College of Atmospheric Sciences Lanzhou University Lanzhou 730000 China School of Mathematics and Computer Science Institute Northwest University for Nationalities Lanahou 730124 China College of Science Inner Mongolia University of Technology Hohhot 010062 China School of Mathematical Sciences Inner Mongolia University Hohhot 010021 China)

On the basis of the quasi-geostrophic vorticity equation,theoretical research has been down upon the evolution of the amplitude of solitary Rossby waves employing the perturbation method,and come to the conclusion tha... 详细信息

关键词： Nonlinear Rossby Waves Variable coefficient KdV equation Time-dependent zonal flow Perturbation method

Study on Spatial Variability of Soil Infiltration coefficient in the Plain of the Yili River Valley in Xinjiang

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Meteorological and Environmental Research 2020年第2期11卷 82-86,89页

作者： Ying LI Yanli YIN Guizhang ZHAO Yuanzhi XU Shiying ZHANG Xi'an Center of Geological Survey China Geological SurveyXi'an 710054China School of Water and Environment Chang'an UniversityXi'an 710054China Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education(Chang'an University) Xi'an 710054China North China University of Water Resources and Electric Power Zhengzhou 450045China

22 typical test points and 8 profiles were selected and arranged in the plain of Yili River Valley based on lithological distribution and sedimentary characteristics to study spatial variability of soil infiltration coefficient. The results show that the infiltration coefficient of different geo-morphic units is as follows: the desert area > the pre-mountain alluvial-proluvial plain > river terrace,which is mainly related to the lithology of aeration zone,buried depth of groundwater and underlying surface. For the infiltration coefficient of different aeration zone mediums,the results are consistent with the changing law. The partition of plain of the Yili River Valley is based on geo-morphic units,infiltration coefficient and the lithology of aeration zone. The maximum infiltration coefficient is concentrated in the desert area,and there is zonal distribution of infiltration coefficient in plane.

关键词： Plain of the Yili River Valley Lithology of aeration zone Infiltration coefficient Spatial variability

Mass attenuation coefficient of olive peat material for absorbing gamma ray energy

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Nuclear Science and Techniques 2019年第7期30卷 27-35页

作者： Mohammad W. Marashdeh Hanan Saleh Department of Physics College of Sciences Imam Mohammad Ibn Saud Islamic University (IMSIU) P.O. Box 90950 Riyadh 11623 Saudi Arabia Department of Radiography Princess Aisha Bint Al-Hussein College of Nursing and Health Sciences Al-Hussein Bin Talal University P.O. Box 20 Ma’an Jordan

The mass attenuation coefficients (l/q) of a natural material, i.e., olive peat, were measured at photon energies of 0.059, 0.356, 0.662, 1.17, and 1.332 MeV and compared with those of concrete and Pb. The experimental samples were irradiated with 214Am, 133Ba, 137Cs, and 60Co point sources using a transmission arrangement. The olive peat samples were obtained from different areas in Jordan, namely Mafraq (sample M), Kerak (sample K), Ajloun (sample A), and Irbid (sample I), and photon energies were measured using a NaI(Tl) scintillation detector with an energy resolution of 7.6% at 662 keV. The differences in the l/q of olive peat samples and the calculated l/q of concrete were consistently within 0.7% at photon energies of 0.356–1.332 MeV. This finding indicates that olive peat can be used in radiation applications in the field of medical physics. Finally, the half-value layer (HVL) of the experimental samples was measured, and results were compared with those of concrete and Pb. Pb and concrete exhibited minimal HVL values due to their high density, and the HVL of olive peat revealed lower shielding effectiveness than that of concrete.

关键词： Olive peat Attenuation coefficient Halfvalue layer Gamma ray

Pocket formula for mass attenuation coefficient, effective atomic number, and electron density of human tissues

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Nuclear Science and Techniques 2019年第3期30卷 1-8页

作者： H.C.Manjunatha L.Seenappa Department of Physics Government College for Women

We have proposed a pocket formula for mass attenuation coefficient(μ/ρ), mass energy absorption coefficient(μ_(en)/ρ), and effective atomic number(Z_(eff)) in different tissues of human organs. We have also assigned a new chemical formula for all studied tissues based on their composition. We have introduced a new parameter called effective composition index(C_(eff)). Based on this, we have introduced a new method to compute the effective atomic number. The evaluated photon interaction parameters are graphically represented. The evaluated average, maximum,minimum, and standard deviations of effective atomic number are tabulated. The proposed formula produces a mass attenuation coefficient, mass energy absorption coefficient, and effective atomic number from their

关键词： Effective atomic number Mass attenuation coefficient Tissues

Research on the effect of the heavy nuclei amount on the temperature reactivity coefficient in a small modular molten salt reactor

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Nuclear Science and Techniques 2019年第9期30卷 83-93页

作者： Meng-Lu Tan Gui-Feng Zhu Yang Zou Xiao-Han Yu Ye Dai Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China University of Chinese Academy of Sciences Beijing 100049 China

Small modular thorium-based graphite-moderated molten salt reactors (smTMSRs), which combine the advantages of small modular reactors and molten salt reactors, are regarded as a wise development path to speed deployment time. In a smTMSR, low enriched uranium and thorium fuels are used in once-through mode, which makes a marked difference in their neutronic properties compared with the case when a conventional molten salt breeder reactor is used. This study investigated the temperature reactivity coefficient (TRC) in a smTMSR, which is mainly affected by the molten salt volume fraction (VF) and the heavy nuclei concentration in the fuel salt (HN). The fourfactor formula method and the reaction rate method were used to indicate the reasons for the TRC change, including the fuel density effect, the fuel Doppler effect, and the graphite thermal scattering effect. The results indicate that only the fuel density has a positive effect on the TRC in the undermoderated region. Thermal scattering from both salt and graphite has a significant negative influence on the TRC in the overmoderated region. The maximal effective multiplication factor, which shows the highest fuel utilization, is located at 10% VF and 12 mol% HN and is still located in the negative TRC region. In addition, on increasing the heavy nuclei amount from 2 mol% HN to 12 mol% HN (VF = 10%), the total TRC undergoes an obvious change from - 11 to - 3 pcm/K, which implies that the change in the HN caused by the fuel feed online should be small to avoid potential trouble in the reactivity control scheme.

关键词： Molten salt reactor Temperature reactivity coefficient Heavy nuclei amount