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Experimental study on instability mechanism and critical intensity of rainfall of high-steep rock slopes under unsaturated conditions

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International Journal of Mining Science and Technology 2023年第10期33卷 1243-1260页

作者： Xiaoshuang Li Qihang Li Yunmin Wang Wei Liu Di hou Wenbo Zheng xiong Zhang School of Urban Construction Changzhou UniversityChangzhou 213164China College of Civil Engineering Qilu Institute of TechnologyJinan 250200China Key Laboratory of Rock Mechanics and Geohazards of Zhejiang Province Shaoxing 312000China School of Resources and Safety Engineering Chongqing UniversityChongqing 400044China Sinosteel Maanshan General Institute of Mining Research Co.LTD. Maanshan 243000China Guizhou Survey and Design Research Institute for Water Resources and Hydropower Guiyang 550001China School of Engineering University of Northern British ColumbiaPrince George V2K3V3Canada

Two critical factors,namely intense precipitation and intricate excavation,can trigger rock mass disasters in mining *** this study,an indoor rainfall system was developed to precisely regulate the flow and intensity of precipitation.A large-scale model experiment was conducted on a self-designed physical simulation experiment platform to investigate the failure and instability of high-steep rock slopes under unsaturated *** real-time reproduction of the progressive failure process in high-steep rock slopes enabled the determination of the critical rainfall intensity and revealed the mechanism underlying slope *** results indicated that rainfall may be the primary factor contributing to rock mass instability,while continuous pillar mining exacerbates the extent of rock mass *** critical failure stage of high-steep rock slopes occurs at a rainfall intensity of 40 mm/h,whereas a rainfall exceeding 50 mm can induce critical instability and precipitation reaching up to 60 mm will result in slope *** improved region growing segmentation method(IRGSM)was subsequently employed for image recognition of rock mass deformation in underground *** an error comparison with the simple linear iterative cluster(SLIC)superpixel method and the original region growing segmentation method(ORGSM)showed that the average identification error in the X and Y directions by the method was reduced significantly(1.82%and 1.80%in IRGSM;4.70%and 6.26%in SLIC;9.45%and 12.40%in ORGSM).Ultimately,the relationship between rainfall intensity and failure probability was analyzed using the Monte Carlo ***,the stability assessment criteria of rock slope under unsaturated condition were quantitatively and accurately evaluated.

关键词： Open-pit to underground mining Rock slope Rainfall infiltration Excavation unloading Similar physical model Image recognition

Subreflector model depending on elevation for the Tianma 65 m Radio Telescope

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Research in Astronomy and Astrophysics 2016年第8期16卷 9-16页

作者： Zheng-xiong Sun jin-Qing Wang Lan Chen Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Shanghai Institute of Technology Shanghai 201400 China

A subreflector adjustment system for the Tianma 65 m radio telescope, administered by Shanghai Astronomical Observatory, has been installed to compensate for gravitational deformation of the main re- flector and the structure supporting the subreflector. The position and attitude of the subreflector are variable in order to improve the efficiency at different elevations. The subreflector model has the goal of improving the antenna＇s performance. A new fitting formulation which is different from the traditional formulation is proposed to reduce the fitting error in the Y direction. The only difference in the subreflector models of the 65 m radio telescope is the bias of a constant term in the Z direction. We have investigated the effect of movements of the subreflector on the pointing of the antenna. The results of these performance measure- ments made by moving the antenna in elevation show that the subreflector model can effectively improve the efficiency of the 65 m radio telescope at each elevation. An antenna efficiency of about 60% at the Ku band is reached in the whole angular range of elevation.

关键词： telescopes -- methods: observational -- methods: data analysis

Maps Preserving Peripheral Spectrum of Generalized Jordan Products of Operators

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Acta Mathematica Sinica,English Series 2015年第6期31卷 953-972页

作者： Wen ZHANG jin Chuan hou Xiao Fei QI Department of Mathematics Shanxi University Department of Mathematics University of TechnologyTaiyuan

Let X1 and X2 be complex Banach spaces with dimension at least three, A1 and A2 be standard operator algebras on X1 and X2, respectively. For k ≥ 2, let （i1, i2, . . . , im） be a finite sequence such that {i1, i2, . . . , im} = {1, 2, . . . , k} and assume that at least one of the terms in （i1, . . . , im） appears exactly once. Define the generalized Jordan productT1 o T2 o··· o Tk = Ti1Ti2··· Tim ＋ Tim··· Ti2Ti1 on elements in Ai. This includes the usual Jordan product A1A2 ＋ A2A1, and the Jordan triple A1A2A3 ＋ A3A2A1. Let Φ ： A1 → A2 be a map with range containing all operators of rank at most three. It is shown that Φ satisfies that σπ（Φ（A1） o··· o Φ（Ak）） = σπ（A1 o··· o Ak） for all A1, . . . , Ak, where σπ（A） stands for the peripheral spectrum of A, if and only if Φ is a Jordan isomorphism multiplied by an m-th root of unity.

关键词： Peripheral spectrum generalized Jordan products Banach spaces standard operatoralgebras

Equivalent Characterization of Centralizers on B(H)

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Acta Mathematica Sinica,English Series 2016年第9期32卷 1113-1120页

作者： Wen Si XU Run Ling AN jin Chuan hou Department of Mathematics Taiyuan University of Technology Taiyuan 030024 P. R. China

Let H be a Hilbert space with dimH ≥2 and Z ∈ B（H） be an arbitrary but fixed operator. In this paper we show that an additive map （I）： B（H）→ B（H） satisfies Ф（AB） = Ф（A）B = AФ（B） for any A, B ∈ B（H） with AB = Z if and only if Ф（AB） = Ф（A）B = AФ（B）, A, B ∈ B（H）, that is, （I） is a centralizer. Similar results are obtained for Hilbert space nest algebras. In addition, we show that Ф（A2） = AФ（A） = Ф（A）A for any A ∈ B（H） with A2 = 0 if and only if Ф（A） = AФ（I） = Ф（I）A, A ∈ B（H）, and generalize main results in Linear Algebra and its Application, 450, 243-249 （2014） to infinite dimensional case. New equivalent characterization of centralizers on B（H） is obtained.

关键词： Centralizers full-centralized points von Neumann algebras nest algebras

A Cyclometalated Iridium（Ⅲ） Complex Serves as a Phosphorescent Probe for Specific Mitochondrial Imaging in Living Cells

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Chinese Journal of Chemistry 2016年第6期34卷 583-588页

作者： jinquan Wang Xiaojuan hou Chengzhi jin Hui Chao Guangdong Provincial Key Laboratory of Biotechnology Candidate Drug Research Guangdong Pharmaceutical University Guangzhou Guangdong 510006 China Huaihua Medical College Huaihua Hunan 418000 China MOE Key Laboratory of Bioinorganic and Synthetic Chemistry School of Chemistry and Chemical Engineering Sun Yat-Sen University Guangzhou Guangdong 510275 China

A new cyclometalated iridium（Ⅲ） complex [Ir（2-pq）2（HPIP）]C1 （lrl, 2-pq=3-phenylisoquinoline, HPIP= 2-（2-hydroxyphenyl）imidazo[4,5-f] 1,10-phenanthroline） was synthesized and applied to image mitochondria in living cells. Irl displayed excellent ability to selectively accumulate in mitochondria of live cells with no requirement of replacement of the culture medium. Due to Irl exhibiting better photostability than the commercially available mitochondrial trackers, this complex could be applicable for the imaging and tracking of the mitochondrial mor- phological changes over long periods of time. In addition, in vitro cytotoxicity investigation revealed that it! showed negligible cytotoxicity at the concentrations employed. Based on these, Irl is suitable for organelle-selective imaging in living cells.

关键词： iridium(Ⅲ) complex phosphorescent probe mitochondria imaging

An Intelligent Scheduling Approach for Electric Power Generation

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Chinese Journal of Electronics 2018年第6期27卷 1170-1175页

作者： YU Li jin Xin LI Zeng xiong Yan HUANG Wenchao College of Computer Science and Engineering Anhui University of Science and Technology School of Computer Science and Technology University of Science and Technology of China

Although China is vigorously developing clean energy and nuclear power, the thermal power generation(mainly coal power) is still the most important power generation method at present. Economic load dispatch(ELD) is a typical optimization problem in power systems which lots of researchers are trying to *** purpose of ELD is to increase the efficiency of thermal power generation under the conditions of load and operational constraints. When it comes to power generation scheduling, manual operation is still the main form,which is inefficient. In order to use a large amount of historical power generation data to improve the efficiency of power generation scheduling and achieve the effect of energy conservation, we propose an intelligent power generation scheduling system based on Deep neural networks(DNN) and Ant colony optimization(ACO). Experiments show that our DNN algorithm can predict the unit coal consumption precisely. Compared with the dynamic programming algorithm and equal differential increment rate algorithm, ACO can complete power generation scheduling tasks more quickly and efficiently.

关键词： Deep learning Ant colony optimization(ACO) Smart grid

Improved Particle Swarm Optimization for Selection of Shield Tunneling Parameter Values

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Computer Modeling in Engineering & Sciences 2019年第2期118卷 317-337页

作者： Gongyu hou Zhedong Xu Xin Liu Cong jin Department of Mechanics and Civil Engineering China University of Mining&TechnologyBeijing100083China.

This article proposes an exponential adjustment inertia weight immune particle swarm optimization(EAIW-IPSO)to enhance the accuracy and reliability regarding the selection of shield tunneling parameter *** to the iteration changes and the range of inertia weight in particle swarm optimization algorithm(PSO),the inertia weight is adjusted by the form of exponential ***,the self-regulation mechanism of the immune system is combined with the PSO.12 benchmark functions and the realistic cases of shield tunneling parameter value selection are utilized to demonstrate the feasibility and accuracy of the proposed EAIW-IPSO *** with other improved PSO indicates that EAIW-IPSO has better performance to solve unimodal and multimodal optimization *** solving the selection of shield tunneling parameter values,EAIW-IPSO can provide more accurate and reliable references for the realistic engineering.

关键词： Inertia weight EAIW-IPSO self-regulation mechanism shield tunneling parameter.

NUMERICAL PREDICTION OF BLADE FREQUENCY NOISE OF CAVITATING PROPELLER

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Journal of Hydrodynamics 2012年第3期24卷 371-377页

作者： YE jin-ming xiong Ying LI Fang WANG Zhan-zhi College of Naval Architecture and Power Naval University of Engineering Wuhan 430033 China

The blade frequency noise of a cavitating propeller in a uniform flow is analyzed in the time domain. The unsteady loading （of a dipole source） and the sheet cavity volume （of a monopole source） on the propeller surface are calculated by a potential-based surface panel method. Then the time-dependent pressure and the cavity volume data are used as the input for the Fowcs Williams-Hawkings formulation to predict the acoustics pressure. The integration of the noise source is performed over the true blade surface rather than the ideal blade surface without thickness. The noise characteristics of the cavitating propeller are discussed. With the sheet cavitation, the thickness （cavitation） noise is larger than the loading noise and is the dominant noise source. The noise directivity is not as clear as that of the noise under a non-cavitation condition. The cavitation noise is attenuated more slowly than the non-cavitation noise.

关键词： propeller surface panel method cavitation noise time domain

Maps Preserving Numerical Radius or Cross Norms of Products of Self-adjoint Operators

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Acta Mathematica Sinica,English Series 2010年第6期26卷 1071-1086页

作者： Kan HE jin Chuan hou Xiu Ling ZHANG Department of Mathematics Shanxi University Taiyuan 030006 P. R. China Department of Applied Mathematics Taiyuan University of Technology Taiyuan 030024 P. R. China Department of Mathematics Shanxi Normal University Linfen 041004 P. R. China

Let H be a complex Hilbert space with dimH ≥3, Bs（H） the （real） Jordan algebra of all self-adjoint operators on H. Every surjective map Ф ： Bs（H）→13s（H） preserving numerical radius of operator products （respectively, Jordan triple products） is characterized. A characterization of surjective maps on Bs （H） preserving a cross operator norm of operator products （resp. Jordan triple products of operators） is also given.

关键词： space of self-adjoint operators numerical radius product of operators