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Simulation of dual transponder carrier ranging measurements

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第10期10卷 1395-1403页

作者： Xiang-yu ZHA Xiao-jun jin Zhong-he jin Department of lnformation Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

The most dominant error source for microwave ranging is the frequency instability of the oscillator that generates the carrier phase signal. The oscillator noise is very difficult to filter due to its extremely low frequency. A dual transponder carrier ranging method can effectively minimize the oscillator noise by combing the reference phase and the to-and-fro measurement phase from the same single oscillator. This method does not require an accurate time tagging system, since it extracts phases on the same satellite. This paper analyzes the dual transponder carrier ranging system by simulation of the phase measurements with comprehensive error models. Both frequency domain and time domain noise transfer characteristics were simulated to compare them with dual one-way ranging. The simulation results in the two domains conformed to each other and demonstrated that a high level of accuracy can also be achieved by use of the dual transponder carder ranging system, with relatively simple instruments.

关键词： Dual transponder carrier ranging Dual one-way ranging Oscillator noise Transfer characteristic

Formation and accumulation of oil and gas in marine carbonate sequences in Chinese sedimentary basins

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Science China Earth Sciences 2012年第3期55卷 368-385页

作者： jin ZhiJun Petroleum Exploration and Production Research Institute China Petroleum&Chemical Corporation(S1NOPEC)Beijing 100083China

Advances in studies of formation and accumulation mechanisms of oil and gas in marine carbonate sequences have led to continuing breakthroughs of petroleum exploration in marine carbonate sequences in Chinese sedimentary basins in recent years. The recently discovered giant Tahe Oil Field and Puguang Gas Field have provided geological entities for further studies of the formation and accumulation of oil and gas in marine carbonate sequences. Marine carbonate sequences in China are characterized by old age, multiple structural deformation, differential thermal evolution of source rocks, various reservoir types (i.e. reef-bank complex and paleo-weathered crust karst reservoir), uneven development of caprocks, especially gypsum seal, and multi-episodes of hydrocarbon accumulation and readjustment. As a result, the formation of hydrocarbon accumulations in the Chinese marine carbonate sequences has the following features: (i) the high-quality marine source rocks of shale and calcareous mudstone are often associated with siliceous rocks or calcareous rocks and were deposited in slope environments. They are rich in organic matter, have a higher hydrocarbon generation potential, but experienced variable thermal evolutions in different basins or different areas of the same basin. (ii) High quality reservoirs are controlled by both primary depositional environments and later modifications including diagenetic modifications, structural deformations, and fluid effects. (iii) Development of high-quality caprocks, especially gypsum seals, is the key to the formation of large-and medium-sized oil and gas fields in marine carbonate sequences. Gypsum often constitutes the caprock for most of large sized gas fields. Given that Chinese marine carbonate sequences are of old age and subject to multiple episodes of structural deformation and superposition, oil and gas tend to accumulate in the slopes and structural hinge zones, since the slopes favor the development of effective assembl

关键词： marine carbonate sequences oil and gas accumulation source rock high quality reservoir caprock depositional slope structural hinge zone

Morphological effects of WO_(3)in metal sulfide-based S-Scheme heterojunctions for boosting photocatalytic hydrogen production

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Journal of Materials Science & Technology 2024年第21期188卷 131-143页

作者： Zhenkun Liu Fei jin Xin Li Peng Zhang Zhiliang jin School of Chemistry and Chemical Engineering North Minzu UniversityYinchuan 750021China Institute of Biomass Engineering Key Laboratory of Energy Plants Resource and UtilizationMinistry of Agriculture and Rural AffairsSouth China Agricultural UniversityGuangzhou 510642China State Centre for International Cooperation on Designer Low-Carbon&Environmental Materials(CDLCEM) School of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001China

In the field of photocatalytic hydrogen production,metal sulfides are frequently utilized,particularly Cd sulfides,which have the benefits of a narrow band gap and a sufficient band *** photocatalysts are required to enhance the situation because it still has a high photogenic carrier recombination rate and has flaws like photocorrosion that need to be *** best morphology combination must be chosen since,as we are all aware,the morphology of the catalyst can significantly alter its *** choose the best morphology,we chose maple leaf CdS and WO_(3)with various morphologies to construct the S-Scheme heterojunctions,and WO_(3)was then applied to other metal *** is concluded that granular WO_(3)–0D and CdS-F have the highest hydrogen evolution activity,which may indicate that 0D has the highest loading capacity and may play a certain supporting role for the catalyst that is easy to agglomerate,exposing more hydrogen evolution active sites to enhance hydrogen *** the same time,the main hydrogen evolution active crystal face of the metal sulfide in the paper is(100)crystal *** the crystal face is exposed,the metal sulfide in the paper has good hydrogen evolution activity,and the hydrogen evolution activity will be greatly reduced after the crystal face is *** established spatial angle between the(100)crystal face exposed by CdS-F and the(111)crystal face exposed by WO_(3)–0D is large,so the highly active crystal face and active site are preserved as much as *** the other hand,WO_(3)decreases the recombination rate of electron-hole pairs in metal sulfide,resulting in a greater contribution of photogenerated electrons to the hydrogen evolution *** Tafel clearly demonstrates the variation of hydrogen production rate control *** offers some suggestions for choosing the photocatalyst’s morphological configuration.

关键词： Metal sulfide WO_(3) Morphology combination Photocatalytic hydrogen production Electron hole pair separation rate

Unitary Scattering Protected by Pseudo-Hermiticity

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Chinese Physics Letters 2022年第3期39卷 82-88页

作者： L.jin School of Physics Nankai UniversityTianjin 300071China

Hermitian systems possess unitary ***,the Hermiticity is unnecessary for a unitary scattering although the scattering under the influence of non-Hermiticity is mostly *** we prove that the unitary scattering is protected by certain type of pseudo-Hermiticity and unaffected by the degree of *** energy conservation is violated in the scattering process and recovers after *** subsystem of the pseudo-Hermitian scattering center including only the connection sites is *** findings provide fundamental insights on the unitary scattering,pseudo-Hermiticity,and energy conservation,and are promising for light propagation,mesoscopic electron transport,and quantum interference in non-Hermitian systems.

关键词： scattering unitary protected

Predicting the alloying element yield in a ladle furnace using principal component analysis and deep neural network

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International Journal of Minerals,Metallurgy and Materials 2023年第2期30卷 335-344页

作者： Zicheng Xin Jiangshan Zhang Yu jin jin Zheng Qing Liu State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Tangshan Branch Hebei Iron and Steel Co.Ltd.Tangshan 063000China

The composition control of molten steel is one of the main functions in the ladle furnace(LF)refining *** this study,a feasible model was established to predict the alloying element yield using principal component analysis(PCA)and deep neural network(DNN).The PCA was used to eliminate collinearity and reduce the dimension of the input variables,and then the data processed by PCA were used to establish the DNN *** prediction hit ratios for the Si element yield in the error ranges of±1%,±3%,and±5%are 54.0%,93.8%,and98.8%,respectively,whereas those of the Mn element yield in the error ranges of±1%,±2%,and±3%are 77.0%,96.3%,and 99.5%,respectively,in the PCA-DNN *** results demonstrate that the PCA-DNN model performs better than the known models,such as the reference heat method,multiple linear regression,modified backpropagation,and DNN ***,the accurate prediction of the alloying element yield can greatly contribute to realizing a“narrow window”control of composition in molten *** construction of the prediction model for the element yield can also provide a reference for the development of an alloying control model in LF intelligent refining in the modern iron and steel industry.

关键词： ladle furnace element yield principal component analysis deep neural network statistical evaluation

Heterogeneous coverage method with multiple unmanned aerial vehicle assisted sink nodes

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High Technology Letters 2019年第4期25卷 395-400页

作者： jin Shan jin Zhigang Electrical Automation and Information Engineering CollegeTianjin UniversityTianjin 300072P.R.China Fire and Rescue Department Bureau of Emergency Management of TianjinTianjin 300090P.R.China

A heterogeneous coverage method with multiple unmanned aerial vehicle assisted sink nodes(MUAVSs)for multi-objective optimization problem(MOP)is proposed,which is based on quantum wolf pack evolution algorithm(QWPEA)and power law entropy(PLE)*** method is composed of preset move and autonomous coordination stages for satisfying non-repeated coverage,connectedness,and energy balance of sink layer critical requirements,which is actualized to cover sensors layer in large-scale outside wireless sensor networks(WSNs).Simulation results show that the performance of the proposed technique is better than the existing related coverage technique.

关键词： wireless sensor network(WSN) coverage multi-unmanned aerial vehicle(MUAV) heterogeneous sink node quantum wolf pack evolution algorithm(QWPEA) power law entropy(PLE)

Fractional sum and fractional difference on non-uniform lattices and analogue of Euler and Cauchy Beta formulas

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Applied Mathematics(A Journal of Chinese Universities) 2021年第3期36卷 420-442页

作者： CHENG jin-fa Department of Mathematics Xiamen UniversityXiamen 361005China

As is well known,the definitions of fractional sum and fractional difference of f(z)on non-uniform lattices x(z)=c1z^(2)+c2z+c3 or x(z)=c1q^(z)+c2q^(-z)+c3 are more difficult and *** this article,for the first time we propose the definitions of the fractional sum and fractional difference on non-uniform lattices by two different *** analogue of Euler’s Beta formula,Cauchy’Beta formula on non-uniform lattices are established,and some fundamental theorems of fractional calculas,the solution of the generalized Abel equation on non-uniform lattices are obtained etc.

关键词： difference equation of hypergeometric type non-uniform lattice fractional sum fractional difference special functions Euler’s Beta formula Cauchy’Beta formula

Elastodynamic analysis of synergistic oscillation system driven by double servomotors for continuous casting mold

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Journal of Iron and Steel Research International 2022年第1期29卷 115-123页

作者： Da-wei Liu Chen Lv jin-ming Zhang Xin jin College of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina National Engineering Technology Research Center of Cold Rolling Strip Equipment and Technology Yanshan UniversityQinhuangdao 066004HebeiChina

Based on the principle of speed superposition,the oscillation system for continuous casting mold synchronously driven by double servomotors can adjust all parameters online with high reliability and high bearing *** elastodynamic model of the oscillation system was presented to analyze the oscillation characteristics affected by multiple ***,the working principle of the system was illustrated,with the kinematic model of the system *** the elastic deformation of mechanical components,the lumped parameter method was used to establish the equivalent component and elastodynamic model of the oscillation *** on Runge–Kutta method,the oscillation response of the system was *** validity of the elastodynamic model was validated by comparing the simulated solution and experimental data,and the oscillation characteristics of the system were analyzed emphatically with model *** results showed that the first three harmonic frequencies of the eccentric shafts are the main cause of harmonic resonance,which has a strong relationship with the system *** increase in the fluctuation coefficients and the decrease in the phase difference enhanced the elastic oscillation of the *** elastic error tends to show linear growth with the increase in the friction force of the slab.

关键词： Continuous casting Mold Non-sinusoidal oscillation Elastic response

A Hardy–Trudinger–Moser Inequality Involving LpNorm in the Hyperbolic Space

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Acta Mathematica Sinica,English Series 2020年第6期36卷 711-722页

作者： Qian jin LUO Department of Mathematics Renmin University of ChinaBeijing 100872P.R.China

Let B be the unit disc in R2,H be the completion of C0∞(B)under the norm||u||=(∫B|▽U|^2dx-∫Bu^2/(1-|x|^2)^2dx)^1/2,U∈C^∞0(B).By the method of blow-up analysis and an argument of rearrangement with respect to the standard hyperbolic metric dv=dx/(1-|x|^2)^2,we prove that,for any fixedα,0≤α*** is an analog of early results of Lu–Yang(Discrete ***.,2009)and Yang(***.,2007),and extends those of Wang–Ye(***.,2012)and Yang–Zhu(*** ***.,2016).

关键词： Hardy–Trudinger–Moser inequality blow-up analysis Hardy space