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Metamerism Appreciation of Jadeite-Jade Green under the Standard Light Sources D_(65),A and CWF

Acta Geologica Sinica(English Edition) 2016年第6期90卷 2097-2103页

作者： GUO Ying WANG Huan LI xiang dong Shirong School of Gemology China University of GeosciencesBeijing Teaching Management Center Beijing City of Arts and Crafts Senior Technical School Department of Science and Technology China University of GeosciencesBeijing

We tested 288 pieces of the polished cabochon jadeite-jade with high quality green and smooth surfaces using the colorimeter Color i5 based on the CIE 1976 L＊a＊b＊ uniform color space. The color changes after alternating three CIE standard light sources D65, A and CWF were compared, and the degree of metamerism was evaluated. The results show that the CIE standard light sources D65, A and CWF increase the chroma of green and turn bluish green into vivid green, which are similar or to nearly colorless and transparent glass-like samples with fine textures. When the three light sources were individually alternated, the lightness of the jadeite-jades showed little change, but the tone changed significantly. Metamerism occurred only in 3 pairs among the 16 samples that were selected by cluster analysis for quality, and the metamerism colors were highly consistent of L＊D65∈（43.47, 46.75）, C＊D65∈（65.20, 68.80） and ho＊D65∈（138.10, 140.23）. We can conclude that the jadeite-jade green gradually turns to blue when the color temperature of the light source increases. But when considering both the light sources and the samples, D65 is more suitable to be the light source of jadeite-jade green when compared with the light sources CWF and A. Compared with the CIE standard green and high chroma green, high-quality jadeite-jade green has a slight yellow tone, low lightness and high chroma. The special metamerism index decreased to 1 when the light source alternated among D65, A and CWF. Therefore, the color of jadeite-jade green might be slightly influenced by alternating of the light sources.

关键词： Jadeite-Jade green CIE standard light source light source alteration special metamerism index

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Receptivity of plane Poiseuille flow to local micro-vibration disturbance on wall

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Water Science and Engineering 2015年第2期8卷 145-150页

作者： Wei-dong Cao Qi-xiang Hu Bing Liu Research Center of Fluid Machinery Engineering and Technology Jiangsu University

The receptivity of plane Poiseuille flow to local single-period micro-vibration disturbances with different phases at the top and bottom walls was investigated through direct numerical simulation of three-dimensional incompressible Navier-Stokes equations. Results show that the disturbance presents a symmetrical distribution in the spanwise direction when the micro-vibration on the wall ends, and the initial disturbance velocities and spatial distribution of the disturbance structure are different at the top and bottom walls. The disturbance＇s velocity, amplitude, and high- and low-speed streaks increase with time, and the amplitude of streamwise disturbance velocity is larger than those of spanwise and vertical disturbance velocities. However, no significant Tollmien-Schlichting wave was found in the flow field. The number of disturbance vortex cores gradually increases with the disturbance area. High-speed disturbance fluid concentrates near the wall and its normal velocity largely points to the wall, while low-speed disturbance fluid largely deviates from the wall. Furthermore, the streamwise velocity profiles near the top and bottom walls both become plump because of the existence of the disturbances, and the streamwise velocity profiles show a trend of evolving into turbulent velocity profiles. The shear stress near the wall increases significantly. The local micro-vibration disturbance on the wall in plane Poiseuille flow can induce the development of a structure similar to turbulent spots.

关键词： Poiseuille flow Disturbance Velocity profile Vortex High-and low-speed streaks

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The Application of Genetic Algorithm on Combination Optimization Model of Multiple Transportation Model

The Application of Genetic Algorithm on Combination Optimiza...

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第25届中国控制与决策会议

作者： CHEN xiang-dong Tianjin University of Technology college of science

ISBN: (纸本)9781467355339

For transportation Networks that can be staging, we suggest a combination optimization model of multiple transportation modes. By constructing a virtual transportation networks, the original problem is converted to a specific shortest path problem. First optimize the network, and then this paper gives the application of genetic algorithm for this problem.

关键词： Staging Virtual Networks Key Point Genetic Algorithm

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Computationally efficient 2-D DOA estimation for non-uniform two-L-shaped array

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The Journal of China Universities of Posts and Telecommunications 2018年第6期25卷 81-89页

作者： Yang Jinsheng xiang Yang Chen Weigang dong Yangyang School of Microelectronics Tianjin UniversityTianjin 300072China Joint Laboratory for Ocean Observation and Detection National Laboratory for Marine Science and TechnologyQingdao 266237China School of Electronics Engineering Xidian UniversityXi'an 710071China

A two-dimensional direction-of-arrival(DOA) estimation method for non-uniform two-L-shaped array is presented in which the element spacing is larger than half-wavelength. To extract automatically paired low-variance cyclically ambiguous direction cosines and high-variance unambiguous direction cosines from the sub-blocks, the proposed method constructs and partitions the cross-correlation matrices. Then, the low-variance unambiguous direction cosines are obtained using the ambiguity resolved technique. Simulation results demonstrate that the proposed method has lower computation complexity and higher resolution than the existing methods especially when the elevation angles are between 70 and 90 degrees.

关键词： aperture extension two-dimensional DOA estimation cross-correlation matrix ambiguity resolved

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M2M:A Simple Matlab-to-MapReduce Translator for Cloud Computing

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Tsinghua Science and Technology 2013年第1期18卷 1-9页

作者： Junbo zhang dong xiang Tianrui Li Yi Pan the School of Information Scienceand Technology Southwest Jiaotong University the Department of Computer Science Georgia State University the School of Software Tsinghua University the School of Information Science and Technology Southwest Jiaotong University Department of Computer Science Georgia State University

MapReduce is a very popular parallel programming model for cloud computing platforms, and has become an effective method for processing massive data by using a cluster of computers. X-to-MapReduce （X is a program language） translator is a possible solution to help traditional programmers easily deploy an application to cloud systems through translating sequential codes to MapReduce codes. Recently, some SQL- to-MapReduce translators emerge to translate SQL-like queries to MapReduce codes and have good performance in cloud systems. However, SQL-to-MapReduce translators mainly focus on SQL-like queries, but not on numerical computation. Matlab is a high-level language and interactive environment for numerical computation, visualization, and programming, which is very popular in engineering. We propose and develop a simple Matlab-to-MapReduce translator for cloud computing, called M2M, for basic numerical computations. M2M can translate a Matlab code with up to 100 commands to MapReduce code in few seconds, which may cost a proficient Hadoop MapReduce programmer some days on coding so many commands. In addition, M2M can also recognize the dependency between complex commands, which is always confusing during hand coding. We implemented M2M with evaluation for Matlab commands on a cluster. Several common commands are used in our experiments. The results show that M2M is comparable in performance with hand-coded programs.

关键词： MapReduce Matlab translator cloud computing

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Rapid Finite Element Analysis of Bulk Metal Forming Process Based on Deformation Theory

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Journal of Iron and Steel Research International 2009年第5期16卷 23-28,42页

作者： WANG Peng dong xiang-huai FU Li-jun Department of Plasticity Technology Shanghai Jiao Tong University Shanghai 200030 China

The one-step finite element method （FEM）, based on plastic deformation theory, has been widely used to simulate sheet metal forming processes, but its application in bulk metal forming simulation has been seldom investigated, because of the complexity involved. Thus, a bulk metal forming process was analyzed using a rapid FEM based on deformation theory. The material was assumed to be rigid-plastic and strain-hardened. The constitutive relationship between stress and total strain was adopted, whereas the incompressible condition was enforced by penalty function. The geometrical non-linearity in large plastic deformation was taken into consideration. Furthermore, the force boundary condition was treated by a simplified equivalent approach, considering the contact history. Based on constraint variational principle, the deformation FEM was proposed. The one-step forward simulation of axisymmettic upsetting process was performed using this method. The results were compared with those obtained by the traditional incremental FEM to verify the feasibility of the proposed method.

关键词： bulk metal forming finite element method (FEM) deformation theory rapid simulation

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Exogenous endophthalmitis caused by Enterococcus casseliflavus:A case report

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World Journal of Clinical Cases 2019年第22期7卷 3904-3911页

作者： Qing-dong Bao Tai-xiang Liu Meng Xie xiang Tian Department of Ophthalmology Affiliated Hospital of Zunyi Medical University

BACKGROUND Endophthalmitis caused by Enterococci is rare,and cases involving vancomycinresistant enterococci are even *** report the first case of Enterococcus casseliflavus endophthalmitis associated with injury caused by a *** also review reported cases of exogenous endophthalmitis caused by Enterococcus casseliflavus and discuss the clinical management and prognosis of this *** SUMMARY A 43-year-old man with no previous visual problems complained of endophthalmitis in his left eye following injury caused by a *** acuity was light perception and B-ultrasonography revealed vitreous opacities with retinal *** was treated with intravitreal vancomycin and ceftazidime after refusing ***,the vitreous opacities and retinal detachment deteriorated and he underwent vitrectomy 5 d ***,advanced rhegmatogenous and tractional retinal detachment with proliferative vitreoretinopathy were *** postoperative day 5,vitreous cultures grew Gram-positive cocci identified as Enterococcus casseliflavus.A 2-wk course of intravenous ampicillin and dexamethasone was *** postoperative day 14,visual acuity improved to hand *** 6 mo post-injury,visual acuity improved to 20/667,but optic atrophy was *** Systemic administration of linezolid in the treatment of Enterococcus casseliflavus endophthalmitis can improve visual ***,intravitreal amikacin should be considered despite concerns of toxicity when oral linezolid fails to prompt improvement.

关键词： Vancomycin-resistant Enterococci Enterococcus casseliflavusendophthalmitis Treatment Case report

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On the magnetic fields of ultraluminous X-ray pulsars

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Research in Astronomy and Astrophysics 2021年第8期21卷 124-134页

作者： Shi-Jie Gao xiang-dong Li School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Key Laboratory of Modem Astronomy and Astrophysics Nanjing UniversityMinistry of EducationNanjing 210023China

So far quite a few ultraluminous X-ray(ULX) pulsars have been *** this work,we construct a super-Eddington,magnetic accretion disk model to estimate the dipole magnetic field of eight ULX pulsars based on their observed spin-up variations and *** obtain two branches of dipole magnetic field *** are distributed in the range of B-(0.156-64.5) × 10^(10) G and-(0.275-79.0) × 10^(13) G corresponding to the low-and high-B solutions *** low magnetic field solutions correspond to the state that the neutron stars are far away from the spin equilibrium,and the high magnetic field solutions are close to the spin *** ultra-strong magnetic fields derived in Be-type ULX pulsars imply that the accretion mode in Be-type ULX pulsars could be more complicated than in the persistent ULX pulsars and may not be accounted for by the magnetized accretion disk *** suggest that the transition between the accretor and the propeller regimes may be used to distinguish between the low-and high-B magnetic field solutions in addition to the detection of the cyclotron resonance scattering features.

关键词： accretion accretion disks X-rays:binaries stars:neutron pulsars:individual(M82 X-2 NGC5907 ULX-1 M51 ULX-7 NGC7793 P13 NGC300 ULX-1 SMC X-3 NGC2403 ULX and Swift J0234.6+6124)

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Assessing the dynamics of O_(2) desorption from cobalt phthalocyanine by in situ electrochemical scanning tunneling microscopy

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Journal of Energy Chemistry 2024年第11期98卷 144-148页

作者： Yu-Qi Wang Yue Feng xiang Wang dong Wang CAS Key Laboratory of Molecular Nanostructure and Nanotechnology CAS Research/Education Center for Excellence in Molecular SciencesBeijing National Laboratory for Molecular Science(BNLMS)Institute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

We report here the in situ electrochemical scanning tunneling microscopy(ECSTM) study of cobalt phthalocyanine(CoPc)-catalyzed O_(2) evolution reaction(OER) and the dynamics of CoPc-O_(2) *** self-assembled CoPc monolayer is fabricated on Au(111) substrate and resolved by ECSTM in 0.1 M KOH *** OH^(-)adsorption on CoPc prior to OER is observed in ECSTM *** OER,the generated O_(2) adsorbed on Co Pc is observed in the CoPc *** step experiment is employed to monitor the desorption of OER-generated O_(2) from CoPc,which results in the decreasing surface coverage of CoPc-O_(2) with *** rate constant of O_(2) desorption is evaluated through data *** insights into the dynamics of Co-O_(2) dissociation at the molecular level via in situ imaging help understand the role of Co-O_(2) in oxygen reduction reaction(ORR) and OER.

关键词： Electrochemical scanning tunneling microscopy Oxygen evolution reaction Cobalt phthalocyanine

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A Stiffness Adjustment Mechanism Based on Negative Work for High-efficient Propulsion of Robotic Fish

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Journal of Bionic Engineering 2018年第2期15卷 270-282页

作者： dong Xu Haining Zeng xiang Peng Ziqing zhao Jingmeng Liu School of Automation Science and Electrical Engineering Beihang University Beijing 100191 China

The applications of robotic fish require high propulsive efficiency mechanism to prolong the mission time. Though many methods were applied, robotic fish still suffers from low efficiency. To improve the efficiency of robotic fish, this paper proposes a variable stiffness mechanism which is based on the negative work. The live fish adjusts its body stiffness to save energy when the muscles do negative work. Inspired by the live fish, a control mechanism based on negative work is proposed to change the stiffness of the robotic fish for higher efficiency. Changing the stiffness of the robotic fish is to change the joint-stiffness. A fuzzy controller is introduced to mimic the variable stiffness mechanism of the fish and depicts the relationship between the stiffness and the negative work. To evaluate the performance of this controller, a two-joint robotic fish model is established based on its kinematic model and hydrodynamic model. The evaluation results show that the robotic fish reduces the energy consumption and improves the propulsion efficiency when introducing the variable stiffness mechanism. Different environments with the control mechanism impact differently on propulsive efficiency. This mechanism may provide a high efficient propulsion control method for the robotic fish.

关键词： robotic fish propulsion efficiency negative work stiffness adjustment

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