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Improved isochronous mass spectrometry with tune measurement
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作者 Han-Yu Deng Yuan-Ming Xing +5 位作者 Xu Zhou Yu-Hu Zhang Xin-Liang Yan Jin-Yang Shi Ting Liao Meng Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第11期174-181,共8页
In conventional isochronous mass spectrometry(IMS)performed on a storage ring,the precision of mass measurements for short-lived nuclei depends on the accurate determination of the revolution times(T)of stored ions.Ho... In conventional isochronous mass spectrometry(IMS)performed on a storage ring,the precision of mass measurements for short-lived nuclei depends on the accurate determination of the revolution times(T)of stored ions.However,the resolution of T inevitably deteriorates due to the magnetic rigidity spread of the ions,limiting the mass-resolving power.In this study,we used the betatron tunes Q(the number of betatron oscillations per revolution)of the ions and established a correlation between T and Q.From this correlation,T was transformed to correspond to a fixed Q with higher resolution.Using these transformed T values,the masses of ^(63)Ge,^(65)As,^(67)Se,and ^(71)Kr agreed well with the mass values measured using the newly developed IMS(Bρ-IMS).We also studied the systematics of Coulomb displacement energies(CDEs)and found that anomalous staggering in CDEs was eliminated using new mass values.This method of T transformation is highly effective for conventional IMS equipped with a single time-of-flight detector. 展开更多
关键词 Isochronous Mass Spectrometry Storage ring TUNE Natural chromaticity Nuclear mass measurement
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Effects of different processing methods on the quality of Polygonatum cyrtonema Hua
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作者 Xin-Ning Zhang Shuang-Hui Shi +13 位作者 Jun-Li Zhang Fan-Miao Kong Hai-Ting Zhu Si-Yuan Ma Yu-Feng Hu Ming-Rui Jiang Hui-Nan Wang Meng-Lin Wang Xiao-Tong Wei Jing-Qiu Zhang Nan Sun Meng-Yu Chen Qian-Qian Liu Ying-Zi Wang 《TMR Modern Herbal Medicine》 CAS 2024年第2期28-34,共7页
Background:In this study,we explored the effects of different processing methods on the quality of Polygonatum cyrtonema Hua(PC),and the role of Huangjiu in the processing procedure.Methods:The sensory characteristics... Background:In this study,we explored the effects of different processing methods on the quality of Polygonatum cyrtonema Hua(PC),and the role of Huangjiu in the processing procedure.Methods:The sensory characteristics of the crude product,steamed product,and wine-processed product of PC were described.The colorimeter was used to analyze the chromatic values of three different processed products on PC.At the same time,the contents of the water extract and alcohol extract were measured separately.The content of three different processing Polygonatum Polysaccharide(PCP)was determined using 0.2%anthrone-sulfuric acid.The correlation difference between the chromatic values and chemical composition of different PC products was analyzed using various analytical methods.Results:The surface colors gradually deepened,the sweetness increased,the viscosity strengthened,and the tongue-numbing sensation disappeared after PC processing.The contents of extract and L^(*) gradually decreased from the crude to the steamed to the wine-processed product,consistent with the pattern of surface color alteration.While,E^(*)ab gradually increased.The content of PCP was crude product>wine-processed product>steamed product.The results of multivariate statistical analysis showed that the samples processed for crude,steamed,and wine-processed product were clustered into three classes.The correlation analysis showed that L^(*)and E^(*)ab were highly significant positively correlated with the content of PCP,and a*was significantly negatively correlated with the content of PCP.Conclusion:The results showed that the wine-processed product had the best quality.The internal quality of the PC was correlated with its characteristics and chromatic value.In this study,we investigated the internal and external quality of three different products of PC in order to provide a reference for further research on the impact of different processing methods on PC quality,the standardization of PC processing,and the role of Huangjiu in the processing of PC. 展开更多
关键词 Polygonatum cyrtonema Hua different products chemical composition chromatic value CHARACTERISTICS
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Influence of Production Sequence of Aluminum Alloy Hot Rolling on Strip Surface Quality
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作者 Hui Song Weixuan Jiang 《Frontiers of Metallurgical Industry》 2024年第1期12-14,共3页
With the intensification of market competition in the aluminum alloy strip processing industry,it is dif-ficult to control the mass production of the same specifications,which is bound to affect the hot rolling produc... With the intensification of market competition in the aluminum alloy strip processing industry,it is dif-ficult to control the mass production of the same specifications,which is bound to affect the hot rolling production.This paper studied the effect of the hot rolling order of aluminum alloy on the surface quality of strip,such as roll printing,color difference,anodic oxidation,etc.,reasonable discharge sequence and corresponding optimization measures were formulated. 展开更多
关键词 hot rolling production sequence surface quality aluminum alloy chromate treatment
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The Erdös-Faber-Lovász Conjecture for Gap-Restricted Hypergraphs
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作者 Zhimin Wang 《Engineering(科研)》 2024年第2期47-59,共13页
An edge coloring of hypergraph H is a function   such that  holds for any pair of intersecting edges . The minimum number of colors in edge colorings of H is called the chromatic index of H and is ... An edge coloring of hypergraph H is a function   such that  holds for any pair of intersecting edges . The minimum number of colors in edge colorings of H is called the chromatic index of H and is denoted by . Erdös, Faber and Lovász proposed a famous conjecture that  holds for any loopless linear hypergraph H with n vertices. In this paper, we show that  is true for gap-restricted hypergraphs. Our result extends a result of Alesandroni in 2021. 展开更多
关键词 Linear Hypergraph Chromatic Index Erdös-Faber-Lovász Conjecture Edge Cardinality
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Mechanical Characterization of Broadband Achromatic Optical Vortex Metalens
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作者 陆哲淳 邓越华 +2 位作者 于洋 黄承志 杨俊波 《Chinese Physics Letters》 SCIE EI CAS CSCD 2023年第11期47-52,共6页
Metalenses,which may effectively manipulate the wavefront of incident light,have been proposed and extensively utilized in the development of various planar optical devices for specialized purposes.However,similar to ... Metalenses,which may effectively manipulate the wavefront of incident light,have been proposed and extensively utilized in the development of various planar optical devices for specialized purposes.However,similar to traditional lenses,the metalens suffers from chromatic aberration problems due to the significant phase dispersion in each unit structure and the limited operational bandwidth.To mitigate the impact of chromatic aberration,we integrate a phase compensation approach with a novel utilization of a phase shift function to define the adjusted phase criterion satisfied by each α-Si resonance unit.This approach may lead to development of an innovative optical tweezer known as an achromatic optical vortex metalens(AOVM),offering reliable focusing capabilities across the 1300 nm and 1600 nm incident light range.Numerical simulations are conducted to investigate the optical properties of 200 nm diameter SiO_(2) particles at the focal plane of the AOVM.The trapping ability of the AOVM is successfully validated,exhibiting favorable characteristics including constant optical force,stable kinematic state of trapped particles,and consistent capture positions,surpassing those of the optical vortex metalens. 展开更多
关键词 CHROMATIC VORTEX utilized
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A novel method for designing crosstalk-free achromatic full Stokes imaging polarimeter
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作者 Jinghua Teng 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第8期1-3,共3页
Metasurface-based polarimetry techniques have attracted lots of interests and been extensively studied in the past years,but are still hampered by narrow operating bandwidth and large crosstalk.Recently,Xian-Gang Luo&... Metasurface-based polarimetry techniques have attracted lots of interests and been extensively studied in the past years,but are still hampered by narrow operating bandwidth and large crosstalk.Recently,Xian-Gang Luo's group proposed a new method of polarization-dependent phase optimization for the design of crosstalk-free,broadband achromatic,and full Stokes imaging polarimeter,which offers a promising platform for a wide range of applications including bio-photonics and integrated optics. 展开更多
关键词 POLAR CHROMATIC method
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Chromatic and achromatic differences of melanin-and carotenoid-based plumage coloration in five minivet species(Pericrocotus spp.)under conspecific and predator visual systems
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作者 Yan Cai Xiangyang Chen +1 位作者 Neng Wu Canchao Yang 《Avian Research》 SCIE CSCD 2023年第1期93-98,共6页
Adaptive mate choice has been accepted as the leading theory to explain the colorful plumage of birds.This theory hypothesizes that conspicuous colors act as signals to advertise the qualities of the owners.However,a ... Adaptive mate choice has been accepted as the leading theory to explain the colorful plumage of birds.This theory hypothesizes that conspicuous colors act as signals to advertise the qualities of the owners.However,a dilemma arises in that conspicuous colors may not only attract mates,but also alert predators.The"private channels of communication"hypothesis proposes that some intraspecific signals may not be visible to heterospecific animals because of different visual systems.To better understand the evolution of plumage colors and sexual selection in birds,here we studied the chromatic difference and achromatic differences of melanin-and carotenoid-based plumage coloration in five minivet species(Pericrocotus spp.)under conspecific and predator visual systems.We found that either the chromatic or achromatic difference among male or female minivets’plumage was consistently higher under conspecific vision than under predator vision for all five studied species of minivets.This result indicated that individual differences in plumage colors of minivets were visible to the conspecific receivers and hidden from potential predators as a result of evolution under predation risk and conspecific communication.However,males were under a higher risk of predation because they were more conspicuous than females to the vision of a nocturnal predator. 展开更多
关键词 Achromatic difference Adaptive mate choice Chromatic difference Omamental plumage Visual modelling
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Single-image night haze removal based on color channel transfer and estimation of spatial variation in atmospheric light
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作者 Shu-yun Liu Qun Hao +6 位作者 Yu-tong Zhang Feng Gao Hai-ping Song Yu-tong Jiang Ying-sheng Wang Xiao-ying Cui Kun Gao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第7期134-151,共18页
The visible-light imaging system used in military equipment is often subjected to severe weather conditions, such as fog, haze, and smoke, under complex lighting conditions at night that significantly degrade the acqu... The visible-light imaging system used in military equipment is often subjected to severe weather conditions, such as fog, haze, and smoke, under complex lighting conditions at night that significantly degrade the acquired images. Currently available image defogging methods are mostly suitable for environments with natural light in the daytime, but the clarity of images captured under complex lighting conditions and spatial changes in the presence of fog at night is not satisfactory. This study proposes an algorithm to remove night fog from single images based on an analysis of the statistical characteristics of images in scenes involving night fog. Color channel transfer is designed to compensate for the high attenuation channel of foggy images acquired at night. The distribution of transmittance is estimated by the deep convolutional network DehazeNet, and the spatial variation of atmospheric light is estimated in a point-by-point manner according to the maximum reflection prior to recover the clear image. The results of experiments show that the proposed method can compensate for the high attenuation channel of foggy images at night, remove the effect of glow from a multi-color and non-uniform ambient source of light, and improve the adaptability and visual effect of the removal of night fog from images compared with the conventional method. 展开更多
关键词 Dehazing image captured at night Chromaticity fusion correction Color channel transfer Spatial change-based atmospheric light ESTIMATION DehazeNet
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Image Fusion Based on NSCT and Sparse Representation for Remote Sensing Data
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作者 N.A.Lawrance T.S.Shiny Angel 《Computer Systems Science & Engineering》 SCIE EI 2023年第9期3439-3455,共17页
The practice of integrating images from two or more sensors collected from the same area or object is known as image fusion.The goal is to extract more spatial and spectral information from the resulting fused image t... The practice of integrating images from two or more sensors collected from the same area or object is known as image fusion.The goal is to extract more spatial and spectral information from the resulting fused image than from the component images.The images must be fused to improve the spatial and spectral quality of both panchromatic and multispectral images.This study provides a novel picture fusion technique that employs L0 smoothening Filter,Non-subsampled Contour let Transform(NSCT)and Sparse Representation(SR)followed by the Max absolute rule(MAR).The fusion approach is as follows:first,the multispectral and panchromatic images are divided into lower and higher frequency components using the L0 smoothing filter.Then comes the fusion process,which uses an approach that combines NSCT and SR to fuse low frequency components.Similarly,the Max-absolute fusion rule is used to merge high frequency components.Finally,the final image is obtained through the disintegration of fused low and high frequency data.In terms of correlation coefficient,Entropy,spatial frequency,and fusion mutual information,our method outperforms other methods in terms of image quality enhancement and visual evaluation. 展开更多
关键词 Remote sensing multispectral image pan chromatic image L0 smoothening filter non-sub sampled contourlet transform sparse representation
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Study of strip-shaped chromatic aberration defects on the surface of an electro-galvanized fingerprint-resistant sheet
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作者 HE Yutian HUANG Shengbiao ZHANG Baoping 《Baosteel Technical Research》 CAS 2023年第2期7-14,共8页
Strip-shaped chromatic aberration defects on the surface of an electro-galvanized fingerprint-resistant sheet were systematically studied using Thermo-Calc thermodynamic calculations,scanning electron microscope and X... Strip-shaped chromatic aberration defects on the surface of an electro-galvanized fingerprint-resistant sheet were systematically studied using Thermo-Calc thermodynamic calculations,scanning electron microscope and X-ray diffractometer analyses,and rapid heat treatment simulation technology.The formation mechanism of these defects was also analyzed.The results show a strong correlation between the defects and the uneven distribution of the Fe(001)component on the surface of the steel substrate.The relatively high proportion of Fe(001)components on the surface of the steel substrate affects the distribution density of the Zn crystal cells in different orientations during the electrodeposition process,which causes the reflection intensity of the light of the galvanized layer to differ from various visual perspectives,and macroscopic strip-shaped chromatic aberration defects are finally formed.The high proportion of the Fe(001)component on the surface of the steel substrate is mainly related to the following two factors.First,when the strip steel is hot-rolled,the finishing hot-rolling temperature is close to theγ→αphase transition temperature.When the local temperature on the upper surface of the strip steel is low,γ+αtwo-phase rolling easily occurs,and this results in an uneven stress distribution between theγandαphases after the hot-rolling process.This uneven distribution of hot-rolling stress results in the formation of a coarse grain structure in the local area on the surface of the hot-rolled sheet,which strongly affects the subsequent cold rolling and annealing process,and the annealed steel sheet substrate ultimately contains a greater proportion of the Fe(001)component.And second,a fast cooling rate(>10 K/s)during the slow cooling stage in the continuous annealing process inhibits the transformation of the Fe(001)to the Fe(111)component on the surface of the cold-rolled steel sheet,and it is then not possible to effectively eliminate the influence of the unevenly distributed Fe(001)component on the surface of the annealed steel sheet(originating from the uneven hot-rolled microstructure).This uneven distribution of the Fe(001)component on the surface of the annealed steel sheet following the continuous annealing heat treatment has a strong effect on the electrodeposition behavior of the Zn crystal cell in the subsequent electroplating process and the formation of macroscopic strip-shaped chromatic aberration defects on the surface of electro-galvanized fingerprint-resistant sheet. 展开更多
关键词 electro-galvanized fingerprint-resistant sheet strip-shaped chromatic aberration defects texture
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Crystallization behaviors of bayerite from sodium chromate alkali solutions 被引量:2
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作者 魏广叶 曲景奎 +4 位作者 郑裕东 齐涛 郭强 韩冰冰 赵宏欣 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第10期3356-3365,共10页
In order to clean production of chromium compounds, it is a critical process to remove aluminates and utilize aluminum compounds from artificial chromate alkali solutions. The effects of Na2 Cr O4 on the neutralizatio... In order to clean production of chromium compounds, it is a critical process to remove aluminates and utilize aluminum compounds from artificial chromate alkali solutions. The effects of Na2 Cr O4 on the neutralization curve, Al(OH)3 precipitation efficiency and induction period of bayerite were investigated. The results indicate that the neutralization curve of the artificial chromate alkali solutions shows three distinct regions and its induction period is longer than that of pure sodium aluminate solutions at the same aluminum concentration. And the decreased temperature and volume fraction of CO2 enhance the particle size of bayerite β-Al(OH)3. Bayerite composed of agglomerates of rods and cone frustums was obtained from alkali metal chromate solutions with 28.5% CO2(volume fraction) at temperatures ranging from 50 °C to 70 °C. Coarse bayerite with particle size(d50) from 24.2 μm to 29.3 μm extremely has few impurities, which is suitable for comprehensive utilization. 展开更多
关键词 chromate alkali solutions BAYERITE CARBONIZATION CRYSTALLIZATION precipitation efficiency
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Preparation of potassium chromate by roasting of carbon ferrochrome 被引量:1
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作者 胡国荣 王家良 +3 位作者 彭忠东 杜柯 王伟刚 蒋庆来 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第3期966-972,共7页
The oxidizing roasting process of carbon ferrochrome to prepare potassium chromate in the presence of potassium carbonate and air was investigated. The effects of reaction temperature, reaction time, mole ratio of pot... The oxidizing roasting process of carbon ferrochrome to prepare potassium chromate in the presence of potassium carbonate and air was investigated. The effects of reaction temperature, reaction time, mole ratio of potassium carbonate to carbon ferrochrome were studied, and thermodynamics and kinetics were also discussed. It was observed that the reaction temperature and reaction time had a significant influence on the roasting reaction of carbon ferrochrome. The reaction mechanism changed greatly as the temperature varied. A two-stage roasting process was favorable for the roasting reaction, and a chromium recovery rate of 97.06% was obtained through this two-stage roasting method. The chromium residue yielded from this method was only 1/3 of the product. Moreover, the component of Fe in the residue was as high as 55.04%. Therefore, it can be easily recovered to produce sponge iron, realizing complete detoxication and zero-emission of chromium residue. 展开更多
关键词 carbon ferrochrome potassium chromate two-stage roasting chromium residue zero-emission
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Crystallization of gibbsite from synthetic chromate leaching solution in sub-molten salt process 被引量:1
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作者 张培育 魏广叶 +2 位作者 郭强 曲景奎 齐涛 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第8期2734-2743,共10页
For the clean and economical production of chromium compounds, it is crucial to remove aluminates from chromate alkali solutions and utilize aluminum-containing compounds. In this work, carbonization was used to remov... For the clean and economical production of chromium compounds, it is crucial to remove aluminates from chromate alkali solutions and utilize aluminum-containing compounds. In this work, carbonization was used to remove aluminates from a synthetic chromate leaching solution containing a high K2O/Al2O3 mole ratio. The influence of reaction temperature, carbonization time, flow rate of carbon dioxide, and seed ratio on the precipitation of Al was investigated. The optimal output was obtained under the following experimental conditions: a reaction temperature of 50 °C, a carbonization time of 100 min, a carbon dioxide flow rate of 0.1 L/min, and a seed ratio of 1.0. Gibbsite was obtained following carbonization. The structure and morphology of the gibbsite were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and laser particle size analyzer. The particle size distribution and morphology of the gibbsite were significantly influenced by the experimental conditions. The gibbsite had a mean particle size (d50) of 16.72μm. The thermal decomposition of the gibbsite was analyzed by XRD and the decomposition path was determined. The obtained coarseα-Al2O3 precipitate, which contains 0.08% Cr2O3 and 0.10% K2O, was suitable for subsequent utilization. 展开更多
关键词 GIBBSITE secondary nucleation CARBONIZATION chromate leaching solution
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DEVELOPMENT AND PRELIMINARY APPLICATION OF OBJECTIFYING SYSTEM FOR TCM COLOR INSPECTION 被引量:2
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作者 郑冬梅 戴振东 王鸿谟 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第4期395-403,共9页
An objectifying system for color inspections of traditional Chinese medicine (CITCM) is developed. The entire system includes two parts : The hardware and the software. The hardware is an image acquiring device und... An objectifying system for color inspections of traditional Chinese medicine (CITCM) is developed. The entire system includes two parts : The hardware and the software. The hardware is an image acquiring device under a standard lighting condition, and it mainly includes a xenon lamp with color temperature of 5 500 K as light source, an integrating sphere used for diffusing light and a high resolution CCD camera. The software is used for digital image processing, and the procedure is divided into three steps. Firstly the skin/non-skin classifi- cation is performed by utilizing the threshold in chrominance channels of the RGB color space. Secondly, the fa- cial features are localized by using the image segmentation and coordinates sorting. Finally, the facial special re- gion(SR) corresponding to five internal organs is achieved by utilizing masks designed to take advantage of mor- phology. Subsequently, the chromaticity is calculated. The system is tested by taking 83 samples of 30 young and 53 elderly people. The experiment shows that there is significant difference of all SRs between the young and the elderly, and the system has better performance for objectifying research of CITCM. 展开更多
关键词 color inspection special region integrating sphere image processing CHROMATICITY significant dif- ference
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Coloring of some integer distance graphs 被引量:1
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作者 许克祥 宋增民 《Journal of Southeast University(English Edition)》 EI CAS 2003年第4期418-422,共5页
An integer distance graph is a graph G(Z, D) with the integer set Z as vertexset, in which an edge joining two vertices u and v if and only if | u - v | ∈ D, where D is a setof natural numbers. Using a related theore... An integer distance graph is a graph G(Z, D) with the integer set Z as vertexset, in which an edge joining two vertices u and v if and only if | u - v | ∈ D, where D is a setof natural numbers. Using a related theorem in combinatorics and some conclusions known to us in thecoloring of the distance graph, the chromatic number _X(G) is determined in this paper that is ofthe distance graph G(Z, D) for some finite distance sets D containing {2, 3} with D = 4 andcontaining {2, 3, 5} with | D | = 5 by the method in which the combination of a few periodiccolorings. 展开更多
关键词 distance graph chromatic number COMBINATION
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联合颈部血管彩超及DSA评估动脉粥样斑块与脑梗死关联性的意义 被引量:9
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作者 方波 《中国实用医药》 2014年第9期4-6,共3页
目的探讨颈部血管彩超及DSA在动脉粥样硬化性脑梗死中的临床应用价值。方法以120例动脉粥样硬化性脑梗死患者为患者组,75例未发生脑梗死患者为对照组,经颈部血管彩超及DSA检查。结果二者颈动脉粥样斑块发生率差异有统计学意义,120例脑... 目的探讨颈部血管彩超及DSA在动脉粥样硬化性脑梗死中的临床应用价值。方法以120例动脉粥样硬化性脑梗死患者为患者组,75例未发生脑梗死患者为对照组,经颈部血管彩超及DSA检查。结果二者颈动脉粥样斑块发生率差异有统计学意义,120例脑梗死患者中,颈动脉及椎动脉粥样斑块发生率为81%,对照组仅有13%。颈动脉斑块最常见颈总动脉分叉处,其次为颈动脉颅内段,椎动脉以起始段多见,其次为基底动脉分布,多以病灶同侧多见,易形成血管狭窄及血流动力学改变。结论颈动脉粥样硬化与脑梗死的发病存在关联性:联合颈部血管彩超与DSA能早期准确发现颈动脉粥样硬化斑块及了解斑块的狭窄率,对预防或治疗脑梗死的发生有重要意义。 展开更多
关键词 颈部血管彩超 动脉粥样硬化性脑梗死 颈动脉狭窄 Double CAROTID CHROMATIC ultrasonic(DCCU)
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交换环的图论性质 被引量:1
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作者 王明生 《北京师范大学学报(自然科学版)》 CAS CSCD 北大核心 1998年第3期319-323,共5页
设R是一个交换环,研究了R的2种图结构.首先,设N表示R的幂零根,,把R的元素作为图的顶点,2个不同的顶点x和y有一边相连接,当且仅当或者,并且x,y中至少1个不是幂零元素,,则证明了下述结果:设R是交换环,使用如上图结构,X(R... 设R是一个交换环,研究了R的2种图结构.首先,设N表示R的幂零根,,把R的元素作为图的顶点,2个不同的顶点x和y有一边相连接,当且仅当或者,并且x,y中至少1个不是幂零元素,,则证明了下述结果:设R是交换环,使用如上图结构,X(R)<+∞当且仅当|R|<+∞,并且此时x(R)=clique(R).其次,把R的元素看作图的顶点,2个不同顶点x和y有边相连,当且仅当Annx+Anny=R.则证明了对交换诺特环R,X(R)<+∞,并猜测x(R)=clique(R). 展开更多
关键词 图的chromatic数 交换环 图论
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Estimation of illumination chromaticity via adaptive reduced relevance vector machine
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作者 丁二锐 曾平 +1 位作者 姚勇 王义峰 《Journal of Southeast University(English Edition)》 EI CAS 2007年第2期202-205,共4页
A new regression algorithm of an adaptive reduced relevance vector machine is proposed to estimate the illumination chromaticity of an image for the purpose of color constancy. Within the framework of sparse Bayesian ... A new regression algorithm of an adaptive reduced relevance vector machine is proposed to estimate the illumination chromaticity of an image for the purpose of color constancy. Within the framework of sparse Bayesian learning, the algorithm extends the relevance vector machine by combining global and local kernels adaptively in the form of multiple kernels, and the improved locality preserving projection (LLP) is then applied to reduce the column dimension of the multiple kernel input matrix to achieve less training time. To estimate the illumination chromaticity, the algorithm is trained by fuzzy central values of chromaticity histograms of a set of images and the corresponding illuminants. Experiments with real images indicate that the proposed algorithm performs better than the support vector machine and the relevance vector machine while requiring less training time than the relevance vector machine. 展开更多
关键词 color constancy illumination estimation chromaticity histogram adaptive reduced relevance vector machine
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Graphs with the Same Color-partition as the Complement of lK_1∪(∪C_(u_i))
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作者 冶成福 张淑敏 火博丰 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第4期52-56,共5页
In this paper, using the properties of chromatic polynomial, we discuss the color-partition of the complement of lK 1∪(∪C u i),and characterize the graph with the same color-partition as the class graph under u... In this paper, using the properties of chromatic polynomial, we discuss the color-partition of the complement of lK 1∪(∪C u i),and characterize the graph with the same color-partition as the class graph under u i≠4k+2. 展开更多
关键词 color-partition chromatically equivalent root of polynomial
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A necessary and sufficient condition for a vertex-transitive graph to be star extremal
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作者 林文松 顾国华 《Journal of Southeast University(English Edition)》 EI CAS 2004年第3期374-377,共4页
A graph is called star extremal if its fractional chromatic number is equal to its circular chromatic number. We first give a necessary and sufficient condition for a graph G to have circular chromatic number V(G)/α(... A graph is called star extremal if its fractional chromatic number is equal to its circular chromatic number. We first give a necessary and sufficient condition for a graph G to have circular chromatic number V(G)/α(G) (where V(G) is the vertex number of G and α(G) is its independence number). From this result, we get a necessary and sufficient condition for a vertex-transitive graph to be star extremal as well as a necessary and sufficient condition for a circulant graph to be star extremal. Using these conditions, we obtain several classes of star extremal graphs. 展开更多
关键词 circular chromatic number fractional chromatic number circulant graph star extremal graph
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