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THE RELATIONSHIP BETWEEN PROJECTIVE GEOMETRIC AND RATIONAL QUADRATIC B-SPLINE CURVES

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Applied Mathematics(A Journal of Chinese Universities) 1998年第4期13卷 445-450页

作者： han xi’AN AND HUANG xiLI Department of Basic Theories Institute of Command and Technology

Abstract For two rational quadratic B spline curves with same control vertexes, the cross ratio of four collinear points are represented: which are any one of the vertexes, and the two points that the ray initialing from the vertex intersects with the corresponding segments of the two curves, and the point the ray intersecting with the connecting line between the two neighboring vertexes. Different from rational quadratic Bézier curves, the value is generally related with the location of the ray, and the necessary and sufficient condition of the ratio being independent of the ray's location is showed. Also another cross ratio of the following four collinear points are suggested, i.e. one vertex, the points that the ray from the initial vertex intersects respectively with the curve segment, the line connecting the segments end points, and the line connecting the two neighboring vertexes. This cross ratio is concerned only with the ray's location, but not with the weights of the curve. Furthermore, the cross ratio is projective invariant under the projective transformation between the two segments.

关键词： Computer aided geometric design rational B-spline curve cross ratio weight

Quantum hyperentanglement and its applications in quantum information processing

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Science Bulletin 2017年第1期62卷 46-68页

作者： Fu-Guo Deng Bao-Cang Ren xi-han Li Department of Physics Applied Optics Beijing Area Major Laboratory Beijing Normal University Beijing 100875 China Department of Physics Capital Normal University Belting 100048 China Department of Physics Chongqing University Chongqing 400044 China Department of Physics and Computer Science Wilfrid Laurier University Waterloo ON N2L 3C5 Canada

Hyperentanglement is a promising resource in quantum information processing with its high capacity character, defined as the entanglement in multiple degrees of freedom(DOFs) of a quantum system, such as polarization, spatial-mode, orbit-angular-momentum, time-bin and frequency DOFs of ***, hyperentanglement attracts much attention as all the multiple DOFs can be used to carry information in quantum information processing fully. In this review, we present an overview of the progress achieved so far in the field of hyperentanglement in photon systems and some of its important applications in quantum information processing, including hyperentanglement generation, complete hyperentangled-Bell-state analysis, hyperentanglement concentration, and hyperentanglement purification for high-capacity long-distance quantum communication. Also, a scheme for hyper-controlled-not gate is introduced for hyperparallel photonic quantum computation, which can perform two controlled-not gate operations on both the polarization and spatial-mode DOFs and depress the resources consumed and the photonic dissipation.

关键词： Quantum hyperentanglement High-capacity quantum communication Concentration and purification Hyperparallel photonic quantumcomputation Quantum information processing

Aerosol optical absorption by dust and black carbon in Taklimakan Desert,during no-dust and dust-storm conditions

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Particuology 2012年第4期10卷 509-516页

作者： Hui Lu Wenshou Wei Mingzhe Liu Weidong Gao xi han xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China Graduate School of the Chinese Academy of Sciences Beijing 100049China Urumqi Institute of Desert Meteorology China Meteorological AdministrationUrumqi 830002China School of Resources and Environment University ofJinanJinan 250000China

Aerosol absorption coefficient σap involves the additive contribution of both black carbon aerosol （BC） and dust aerosol. The linear statistical regression analysis approach introduced by Fialho et al. （2005） is used to estimate the absorption exponents of BC and dust aerosol absorption coefficients, and further to separate the contributions of these two types of aerosols from the total light absorption coefficient measured in the hinterland of Taklimakan Desert in the spring of 2006. Absorption coefficients are measured by means of a 7-wavelength Aethalometer from 1 March to 31 May and from 1 November to 28 December, 2006. The absorption exponent of BC absorption coefficient α is estimated as （-0.95 ± 0.002） under background weather （supposing the observed absorption coefficient is due only to BC）; the estimated absorption exponent of dust aerosol absorption coefficient/5 during the 6 dust storm periods （strong dust storm） is （-2.55 ± 0.009）. Decoupling analysis of the measured light absorption coefficients demonstrates that, on average, the light absorptions caused by dust aerosol and BC make up about 50.5% and 49.5% respectively of the total light absorption at 520 nm; during dust weather process periods （dust storm, floating dust, blowing dust）, the contribution of dust aerosol to absorption extinction is 60.6% on average; in the hin- terland of desert in spring, dust aerosol is also the major contributor to the total aerosol light absorption, more than that of black carbon aerosol.

关键词： Black carbonDustAbsorption coefficientAbsorption exponent of absorptioncoefficientDecoupling of absorption coefficient

Method for calculating non-point source pollution distribution in plain rivers

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Water Science and Engineering 2011年第1期4卷 83-91页

作者： Long-xi han Fei HUO Juan SUN State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 P. R. China Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes Ministry of Education Hohai University Nanjing 210098 P. R. China College of Environmental Science and Engineering Hohai University Nanjing 210098 P. R. China

The land area in a river network is divided into certain-scale square cells for the sake of precision, and, based on the physical mechanisms of rainfall-runoff processes and runoff pollution, the non-point source pollution from cells is estimated using the export coefficients of different land use types. The non-point source pollution from a land cell should all go into the closest fiver reach, so it is distributed according to the terrain of the plain river network area and the positions of land cells and river network reaches. A relationship between a single land cell and its pollution-receiving reach can be determined using this system. In view of the above, a spatial distribution model of the rainfall runoff and non-point source pollution in reaches of a plain river network area was established. This model can provide technological support for further research on the dynamic effects of non-point source pollution on water quality.

关键词： non-point source pollution pollution loads, export coefficients plain river network

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魔芋软腐病的病原检测及治理策略

山西农业大学学报(自然科学版) 2025年第1期45卷 10-20页

作者：马晓冉金鑫韩茜牛义马冠华郑阳陈国康西南大学植物保护学院重庆400716 宜宾市农业科学院四川宜宾644600 西南大学园艺园林学院重庆400716 重庆市农业科学院蔬菜花卉研究所重庆401329

魔芋是我国重要的经济作物之一,可以大量合成葡甘聚糖。魔芋软腐病是魔芋生产上最为严重的土传病害,对魔芋产量造成重大的损失,严重制约了我国魔芋产业的发展。因此,魔芋软腐病的防治是魔芋生产中的一项重要工作。本文主要从魔芋软腐病... 详细信息

魔芋是我国重要的经济作物之一,可以大量合成葡甘聚糖。魔芋软腐病是魔芋生产上最为严重的土传病害,对魔芋产量造成重大的损失,严重制约了我国魔芋产业的发展。因此,魔芋软腐病的防治是魔芋生产中的一项重要工作。本文主要从魔芋软腐病病原检测技术、防治策略等方面进行综述,除常规PCR检测技术外,还阐述新的检测技术在魔芋软腐病上的应用,并概述了目前主要防治魔芋软腐病方法,例如化学防治、生物防治、农业防治等,以期为魔芋软腐病的病原快速检测和综合防控提供指导意义。

关键词：魔芋软腐病病原菌鉴定方法综合防控

维普期刊数据库博看期刊

CPT-11 Chemotherapy Rescued A Patient with Atypical Sclerosing Epithelioid Fibrosarcoma from Emergent Condition

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Chinese Journal of Cancer Research 2012年第3期24卷 253-256页

作者： Chun-hua Pan xi-qun han Jian-sheng Li Department of Medical Oncology Affiliated Tumor Hospital of Guangzhou Medical CollegeGuangzhou 510095China Department of Pathology School of Basic Medical SciencesSouthern Medical UniversityGuangzhou 520515China Department of Image Affiliated Tumor Hospital of Guangzhou Medical CollegeGuangzhou 510095China

Sclerosing epithelioid fibrosarcoma （SEF） is a rare and poorly defined variant of fibrosarcoma, but generally insensitive to chemotherapy and progresses with poor prognosis. We report the marvelous effect of irinotecan hydrochloride （CPT-11） chemotherapy in rescuing a patient with atypical SEF from emergent condition, who underwent recurrences after several treatment methods. Small dose of CPT-11 was administered to the patient, with which, the size of superficial mass （cervical lymph node） gradually decreased observed by the naked eyes in 5 days. X-ray and CT image proved a marked reduction in the size of the tumor. CPT-11 is valuable for the treatment of this aggressive sarcoma. In condition of emergency caused by sarcoma oppression, administering a tolerable small dose of topoisomerase I-inhibiting drug could be a beneficial choice.

关键词： Sclerosing epithelioid fibrosarcoma CPT- Chemotherapy

Robustness analysis of interdependent PV grids and communication network based on complex network

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The Journal of China Universities of Posts and Telecommunications 2018年第5期25卷 60-66页

作者： Fan xinwen Wen xiangming Lu Zhaoming Sun Chunlei han xi School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing Key Laboratory of Network System Architecture and Convergence Beijing University of Posts and Telecommunications Beijing Laboratory of Advanced Information Networks Beijing University of Posts and Telecommunications Electronic Information Engineering North China University of Technology

Currently,the photovoltaic（ PV） cloud network is an important research point in energy Internet. From the perspective of the robustness analysis of PV cloud network,traditional robustness index,the relative size of the giant connected component before and after the cascading,which is focused on the giant component,is not appropriate for the distributed PV network because of the big difference between PV generators and large power grid. In this paper,a new index is proposed,the minimum removed nodes number（ MRNN）,which can make the entire system collapse,to evaluate the robustness of PV cloud network system. Simulation results show that MRNN can clearly indicate the system robustness under different parameters.

关键词： cascading failure interdependent system minimum removed nodes number (MRNN)

Geochemical characteristics of the fluid inclusions in the Gangxi Fault Belt, Huanghua Depression, Bohai Bay Basin, China

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第7期8卷 1011-1020页

作者： DING Wei-wei DAI Jin-xing CHU Feng-you han xi-qiu Key Laboratory of Submarine Geoscience the State Oceanic Administration Hangzhou 310012 China Department of Earth Science Zhejiang University Hangzhou 310027 China

We studied the geochemical characteristics of the fluid inclusions in the Ordovician carbonates and the Oligocene Shahejie Formation sandstones from 15 wells in the Gangxi Fault Belt, Huanghua Depression. The fluid inclusions are all sec- ondary with gas/liquid ratio of 5%~10%. Base on Raman they are mainly composed of H2O, CO2 and CH4. The homogenization temperatures, combined with burial and geothermal history of the host rock, indicate that the fluid flows in the Shahejie Formation and the Ordovician carbonates were trapped in Neocene. Using a VG5400 mass spectrometer, the helium isotopic compositions were analyzed. Interpretation of results suggested a significant amount of mantle-derived helium mainly accumulating in the intersections of the NWW trending Xuzhuangzi and NE trending Gangxi faults. The maturity of hydrocarbon decreases from the intersection to the outside pointing out that the fluid related to the NWW trending Xuzhuangzi and NE trending Gangxi faults. These factors implied the fluid inclusions have a close relationship to the local tectonic setting. Gangxi Fault Belt experienced intensive Neo-tectonic activities in Cenozoic. Widespread faulted-depressions and strong volcanic eruptions manifested its tec- tonic status of extensional stress field. Mantle uplift caused the movement of magma that carried mantle-derived gases and deep heat flows, the deep-rooted tension faults provided the passages for the gases and heat flows to shallow crust levels.

关键词： Gangxi Fault Belt Fluid inclusion Composition Mantle-derived Maturity Local tectonic setting

Energy Budget over Seasonal Snow Surface at an Open Site and Beneath Forest Canopy Openness during the Snowmelt Period in Western Tianshan Mountains,China

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Journal of Mountain Science 2015年第2期12卷 298-312页

作者： LU Heng WEI Wen-shou LIU Mingzhe han xi HONG Wen xinjiang Institute of Ecology and Geography Chinese Academy of Sciences University of Chinese Academy of Sciences Institute of Desert Meteorology China Meteorological Administration Tianshan Station for Snow & Avalanche Research

In this study, meteorological factors and snowmelt rate at an open site on sunny slope(OPS) and beneath forest canopy openness on shady slope(BFC) were measured using an automatic weather station and snow lysimeter during the snowmelt period in 2009, 2010 and 2013. The energy budget over snow surface was calculated according to these meteorological datasets. The analysis results indicated that the net shortwave radiation(K) and sensible heat flux(H) were energy sources, and the latent heat flux(LVE) was energy sinks of snow surfaces at all sites. The net longwave radiation(L) was energy sink at OPS and 80% BFC, but energy source at 20% BFC. The gain of K, H, and the loss of LVE at BFC were obviously lower than those at OPS. The L was the maximum difference of energy budget between snow surface at BFC and OPS. In warm and wet years, the most important factor of the energy budget variation at OPS was air humidity and the second mostimportant factor was air temperature. However, the ground surface temperature on the sunny slope was the most important factor for L and energy budget at BFC. With the increases in forest canopy openness and the slope of adjacent terrains, the influences of ground surface temperature on the sunny slope on L and the energy budget over snow surface at BFC increased, especially when the snow cover on the sunny slope melts completely.

关键词： Energy budget Seasonal snow Snowmelt period Tianshan Mountains