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外分式复式交分道岔非集中控制电路研究
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作者 吕永宏 刘红燕 《铁道标准设计》 北大核心 2009年第1期89-90,共2页
外分式复式交分道岔是一种新型研制开发的道岔,安装简单,故障率低,可以很大程度提高列车通过道岔的速度。为了保证列车的运行安全,外分式复式交分道岔必须有专门的控制系统来保证安全转换,为此结合厂矿企业运输的特点,专门研制了一种特... 外分式复式交分道岔是一种新型研制开发的道岔,安装简单,故障率低,可以很大程度提高列车通过道岔的速度。为了保证列车的运行安全,外分式复式交分道岔必须有专门的控制系统来保证安全转换,为此结合厂矿企业运输的特点,专门研制了一种特殊的控制电路。主要针对这种特殊的控制电路系统构成、控制方法和电路原理进行详细介绍。 展开更多
关键词 外分式 复式交分道岔 控制电路
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外分式复式交分道岔及其控制技术在宝钢的应用研究
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作者 刘峰 《宝钢技术》 CAS 2006年第6期51-55,共5页
为解决宝钢分公司一炼钢区域铁水运输能力“瓶颈”问题,需要将前扒渣间与脱硫间铁路线路实施贯通改造。由于该区域受到总图布局限制,铁路贯通改造的难度极大,通过对各种可能实施改造方案进行详细调研、比较、分析,开发了一种适应铁水运... 为解决宝钢分公司一炼钢区域铁水运输能力“瓶颈”问题,需要将前扒渣间与脱硫间铁路线路实施贯通改造。由于该区域受到总图布局限制,铁路贯通改造的难度极大,通过对各种可能实施改造方案进行详细调研、比较、分析,开发了一种适应铁水运输条件的新型外分式复式交分道岔及其自选进路控制系统。通过运用,不仅使现有设备设施的拆迁工作量减少到最低,而且满足了铁路行车安全、效率要求,提高了铁水预处理效率,降低铁水物流运输和预处理成本。 展开更多
关键词 铁水 铁路运输 外分式复式交分道岔 车上转换装置 进路控制
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Three-dimensional analysis of natural convection in nanofluid-filled parallelogrammic enclosure opened from top and heated with square heater 被引量:1
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作者 Abdullah A.A.A AL-RASHED Walid HASSEN +3 位作者 Lioua KOLSI Hakan F. OZTOP Ali J. CHAMKHA Nidal ABU-HAMDEH 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第5期1077-1088,共12页
A numerical study based on the finite volume method has been performed to study the three-dimension natural convection in a parallelogrammic top side opened cavity filled nanofluid with partially heated square at the ... A numerical study based on the finite volume method has been performed to study the three-dimension natural convection in a parallelogrammic top side opened cavity filled nanofluid with partially heated square at the bottom side.Results are obtained for different governing parameters such as nanoparticle concentration (φ) from 0 to 0.05,inclination angle of the back and front walls (α) from 5° to 75°,Rayleigh number from 10^3 to 10^5,and length of heater changer from 0.1 to 1.The main finding from the obtained result showed that the inclination angle and nanoparticle volume fraction affect the flow structure and enhance the heat transfer. 展开更多
关键词 3D analysis open enclosure partial heating PARALLELOGRAM nanofluids
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On the Geometrical Meaning of the Dynamic Equations in Analytical Mechanics
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作者 刘书振 陈书勤 王惠民 《Chinese Quarterly Journal of Mathematics》 CSCD 1993年第3期66-70,共5页
In this paper,the modern geometrical structure of analytical mechanics,the exterior differential forms and the geometrical meaning of dynamic equations are briefly discussed.
关键词 FIBRE tangent and cotangent bundles symplectic manifolds riemannian kinemic metric integral manifolds
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Jacquard image segmentation using Mumford-Shah model
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作者 冯志林 尹建伟 +1 位作者 陈刚 董金祥 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第2期109-116,共8页
Jacquard image segmentation is one of the primary steps in image analysis for jacquard pattern identification. The main aim is to recognize homogeneous regions within a jacquard image as distinct, which belongs to dif... Jacquard image segmentation is one of the primary steps in image analysis for jacquard pattern identification. The main aim is to recognize homogeneous regions within a jacquard image as distinct, which belongs to different patterns. Active contour models have become popular for finding the contours of a pattern with a complex shape. However, the performance of active contour models is often inadequate under noisy environment. In this paper, a robust algorithm based on the Mumford-Shah model is proposed for the segmentation of noisy jacquard images. First, the Mumford-Shah model is discretized on piecewise linear finite element spaces to yield greater stability. Then, an iterative relaxation algorithm for numerically solving the discrete version of the model is presented. In this algorithm, an adaptive triangular mesh is refined to generate Delaunay type triangular mesh defined on structured triangulations, and then a quasi-Newton numerical method is applied to find the absolute minimum of the discrete model. Experimental results on noisy jacquard images demonstrated the efficacy of the proposed algorithm. 展开更多
关键词 Mumford-Shah model Image segmentation Active contour Variational method Jacquard image
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A novel face recognition method with feature combination 被引量:2
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作者 李文书 周昌乐 许家佗 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第5期454-459,共6页
A novel combined personalized feature framework is proposed for face recognition (FR). In the framework, the proposed linear discriminant analysis (LDA) makes use of the null space of the within-class scatter matrix e... A novel combined personalized feature framework is proposed for face recognition (FR). In the framework, the proposed linear discriminant analysis (LDA) makes use of the null space of the within-class scatter matrix effectively, and Global feature vectors (PCA-transformed) and local feature vectors (Gabor wavelet-transformed) are integrated by complex vectors as input feature of improved LDA. The proposed method is compared to other commonly used FR methods on two face databases (ORL and UMIST). Results demonstrated that the performance of the proposed method is superior to that of traditional FR ap- proaches 展开更多
关键词 Fisher discriminant criterion Face recognition (FR) Linear discriminant analysis (LDA) Principal component analysis (PCA) Small sample size (SSS)
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Inference of Reference Conditions for Nutrient Concentrations of Chaohu Lake Based on Model Extrapolation
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作者 ZHOU Yuliang JIN Juliang +3 位作者 LIU Li ZHANG Libing He Jun WANG Zhesun 《Chinese Geographical Science》 SCIE CSCD 2013年第1期35-48,共14页
In the mid-eastern China,there are few or no lakes which are in the absence of anthropogenic disturbances,or their sediments remain undisturbed.As a result,the reference lakes distribution and paleolimnological recons... In the mid-eastern China,there are few or no lakes which are in the absence of anthropogenic disturbances,or their sediments remain undisturbed.As a result,the reference lakes distribution and paleolimnological reconstruction approaches usually are inappropriate to estimate lake reference conditions for nutrients.This yields the necessity of using the extrapolation methods to estimate the lake reference conditions for nutrients within those regions.The lake reference conditions for nutrients could be inferred inversely from the law of mass conservation,current lake nutrient concentration,and the loadings from watershed.Considering the scarcity of hydrological and water quality data associated with lakes and watersheds in China,as well as the low requirement of the watershed nutrient loadings models for these data,the soil conservation service(SCS) distributed hydrological model and the universal soil loss equation(USLE) were applied.The SCS model simulates the runoff process of the watershed,thereby calculating dissolved nutrients annually.The USLE estimates the soil erosion and particulate nutrients annually in a watershed.Then,with the loadings from atmospheric deposition and point source,the previous annual average nutrient concentrations could be acquired given the current nutrient concentrations in a lake.Therefore,the nutrient reference conditions minimally impacted by human activities could be estimated.Based on the proposed model,the reference conditions for total nitrogen and total phosphorus of Chaohu Lake,Anhui Province,China are 0.031 mg/L and 0.640 mg/L,respectively.The proposed reference conditions estimation model is of clear physical concept,and less data required.Thus,the proposed approach can be used in other lakes with similar circumstances. 展开更多
关键词 reference conditions soil conservation service universal soil loss equation total phosphorus total nitrogen Chaohu Lake
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The(0,1)Type Green Form of a Complex Projective Space CP^n
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作者 卢克平 《Chinese Quarterly Journal of Mathematics》 CSCD 1993年第4期65-70,共6页
In this paper,the(0.1)-form heat kernel of a complex projective space of dimensions n is constructed cxplicitely.As an application of the(0.1)-form heat kernel,the(0.1)type Green Form of CP~
关键词 fubini-study metric (0 1)type Green Form (0 1)-form heat kernel
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A New Self Adaptive Inertial Subgradient Extragradient Iterative Algorithm for Solving Variational Inequalities of Pseudomonotone Mappings in Real Hilbert Spaces
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作者 HU Shaotao WANG Yuanheng +1 位作者 TANG Yan JING Ping 《数学进展》 CSCD 北大核心 2024年第6期1285-1304,共20页
The main purpose of this paper is to introduce and deal with a self adaptive inertial subgradient extragradient iterative algorithm with a new and interesting stepsize rule in real Hilbert spaces.Under some proper con... The main purpose of this paper is to introduce and deal with a self adaptive inertial subgradient extragradient iterative algorithm with a new and interesting stepsize rule in real Hilbert spaces.Under some proper control conditions imposed on the coefficients and operators,we prove a new strong convergence result for solving variational inequalities with regard to pseudomonotone and Lipschitzian operators.Moreover,some numerical simulation results are given to show the rationality and validity of our algorithm. 展开更多
关键词 strong convergence variational inequality extragradient method pseudomonotone operator Hilbert space
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A twin-channel difference model for cross-calibration of thermal infrared band 被引量:2
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作者 LI JiaGuo GU XingFa +4 位作者 YU Tao LI XiaoYing GAO HaiLiang LIU Li XU Hui 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第7期2048-2056,共9页
Based on the conduction and transformation of the thermal infrared radiative transfer equation of water target,a twinchannel difference model(DM) was proposed to improve the calibration precision by conquering the lim... Based on the conduction and transformation of the thermal infrared radiative transfer equation of water target,a twinchannel difference model(DM) was proposed to improve the calibration precision by conquering the limitation that the atmospheric condition when image is acquiring cannot be truly obtained in the traditional radiometric simulation calibration method.The analysis of surface,atmosphere and top-of-atmosphere(TOA) radiative energy decomposition demonstrated that the apparent TOA radiance of the uncalibrated channel is the differential combination of two reference channels.The DM avoids impacts from atmospheric temperature and density.The only impact is from water vapor(WV) content.Based on the fitting error analysis of 742 mid-latitude atmospheric profiles(column WV content:0-5×10 3 atm cm) selected from TIGR database,the DM is insensitive to WV content.The maximum error is less than 0.2 K when the view zenith angels(VZAs) of reference channels and uncalibrated channel are less than 30.The error becomes 0.3 K when VZAs range from 30 to 40 and 0.6 K when VZAs are in 40-50.Because the uncertainty increases when VZAs are larger than 50,the best range of VZAs is 30-50.The vicarious calibration results at Lake Qinghai field indicated that the calibration precision of the DM cross-calibration by using MODIS bands 31 and 32 as reference channels to calibrate IRS band 08 is similar to that of vicarious calibration.Therefore,the DM is a reliable alternative tool for sensor on-orbit calibration and validation with high precision and frequency. 展开更多
关键词 remote sensing CROSS-CALIBRATION difference model IRS MODIS
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The Heat Transfer Coefficients of the Heating Surface of 300 MWe CFB Boiler 被引量:3
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作者 WU Haibo ZHANG Man +1 位作者 LU Qinggang SUN Yunkai 《Journal of Thermal Science》 SCIE EI CAS CSCD 2012年第4期368-376,共9页
A study of the heat transfer about the heating surface of three commercial 300 MWe CFB boilers was conducted in this work. The heat transfer coefficients of the platen heating surface, the external heat exchanger (EHE... A study of the heat transfer about the heating surface of three commercial 300 MWe CFB boilers was conducted in this work. The heat transfer coefficients of the platen heating surface, the external heat exchanger (EHE) and cyclone separator were calculated according to the relative operation data at different boiler loads. Moreover, the heat transfer coefficient of the waterwall was calculated by heat balance of the hot circuit of the CFB boiler. With the boiler capacity increasing, the heat transfer coefficients of these heating surface increases, and the heat transfer coefficient of the water wall is higher than that of the platen heating surface. The heat transfer coefficient of the EHE is the highest in high boiler load, the heat transfer coefficient of the cyclone separator is the lowest. Because the fired coal is different from the design coal in No.1 boiler, the ash content of the fired coal is much lower than that of the design coal. The heat transfer coefficients which calculated with the operation data are lower than the previous design value and that is the reason why the bed temperature is rather high during the boiler operation in No.1 boiler. 展开更多
关键词 CFB boiler heating surface heat transfer coefficient CALCULATION
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Protective immunity against Rickettsia heilongjiangensis in a C3H/HeN mouse model mediated by outer membrane protein B-pulsed dendritic cells 被引量:2
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作者 MENG YanFen XIONG XiaoLu +4 位作者 QI Yong DUAN ChangSong GONG WenPing JIAO Jun WEN BoHai 《Science China(Life Sciences)》 SCIE CAS CSCD 2015年第3期287-296,共10页
Rickettsia heilongjiangensis is an obligate intracellular bacterium that causes Far-Eastern tick-borne spotted fever. Outer membrane protein B(Omp B) is an important surface protein antigen of rickettsiae. In the pres... Rickettsia heilongjiangensis is an obligate intracellular bacterium that causes Far-Eastern tick-borne spotted fever. Outer membrane protein B(Omp B) is an important surface protein antigen of rickettsiae. In the present study, the omp B gene of R. heilongjiangensis was divided into four fragments, resulting in four recombinant proteins(OmpB-p1, Omp B-p2, Omp B-p3, and Omp B-p4). Each Omp B was used in vitro to stimulate murine bone marrow-derived dendritic cells(BMDCs) of C3H/He N mice, and the Omp B-pulsed BMDCs were transferred to naive C3H/He N mice. On day 14 post-transfer of BMDCs, the mice were challenged with R. heilongjiangensis and the rickettsial loads in the mice were quantitatively determined on day 7 post-challenge. Mice receiving BMDCs pulsed with Omp B-p2, Omp B-p3, or Omp B-p4 exhibited significantly lower bacterial load compared with mice receiving Omp B-p1-pulsed BMDCs. CD4+ and CD8+ T cells isolated from the spleen of C3H/He N mice receiving BMDCs pulsed with each OmpB were co-cultured with BMDCs pulsed with the respective cognate protein. In flow cytometric analysis, the expression level of CD69 on CD4+ or CD8+ T cells from mice receiving BMDCs pulsed with Omp B-p2, OmpB-p3, or Omp B-p4 was higher than that on cells from mice receiving Omp B-p1-pulsed BMDCs, while the expression level of tumor necrosis factor(TNF)-α on CD8+ T cells and interferon(IFN)-γ on the CD4+ and CD8+ T cells from mice receiving Omp B-p2,-p3, or-p4 was significantly higher than on cells from mice receiving Omp B-p1-pulsed BMDCs. Our results suggest that the protective Omp Bs could activate CD4+ and CD8+ T cells and drive their differentiation toward CD4+ Th1 and CD8+ Tcl cells, respectively, which produce greater amounts of TNF-α and, in particular, IFN-γ, to enhance rickettsicidal activity of host cells. 展开更多
关键词 Rickettsia heilongjiangensis dendritic cells outer membrane protein protective immunity
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Optical characteristics and environmental pollutants detection of porous silicon microcavities
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作者 HUANG JianFeng, LI Sha, CHEN QingWei & CAI LinTao CAS Key Laboratory of Health Informatics Shenzhen Key Laboratory of Cancer Nanotechnology Institute of Biomedical and Health Engineering, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China 《Science China Chemistry》 SCIE EI CAS 2011年第8期1348-1356,共9页
Porous silicon microcavities (PSM) optical crystals consisting of a Fabry-Perot microcavity embedded between two distributed Bragg reflectors have been fabricated by electrochemical etching. Scanning electron microsco... Porous silicon microcavities (PSM) optical crystals consisting of a Fabry-Perot microcavity embedded between two distributed Bragg reflectors have been fabricated by electrochemical etching. Scanning electron microscopy (SEM) clearly depicted their physical sandwich construction. The optical feature of the PSM structure was tuned by varying the anodization parameters. Through proper thermal oxidation and surface chemical modifications, the resulting structures were employed as optical sensors for the detection of environmental pollutants including volatile organic vapors (i.e. acetonitrile, toluene, cyclohexane, chloroform, acetone and ethanol) and interior decoration gases (i.e. toluene, ammonia and formaldehyde). Fourier transform infrared spectroscopy (FTIR) spectra confirmed the effective thermal annealing and surface modification chemistry, and the sensing process was accompanied by recording the modified structures' optical responses when exposed to target analytes. The PSM optical sensors showed good stability, sensitivity and selectivity, implying promising applications in gas sensing and en- vironmental monitoring. 展开更多
关键词 porous silicon microcavity optical sensor thermal oxidation surface modification environmental pollutants detection
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